diff options
| author | Kees Cook <kees+treewide@kernel.org> | 2026-09-02 15:31:14 -0700 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2026-09-04 21:37:00 -0700 |
| commit | 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch) | |
| tree | c65086f9bdcd48c6360fb7cb4598bca084da1f32 /drivers/base/power | |
| download | linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip | |
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci
This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.
Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.
Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'drivers/base/power')
| -rw-r--r-- | drivers/base/power/Makefile | 9 | ||||
| -rw-r--r-- | drivers/base/power/clock_ops.c | 732 | ||||
| -rw-r--r-- | drivers/base/power/common.c | 457 | ||||
| -rw-r--r-- | drivers/base/power/generic_ops.c | 239 | ||||
| -rw-r--r-- | drivers/base/power/main.c | 2442 | ||||
| -rw-r--r-- | drivers/base/power/power.h | 177 | ||||
| -rw-r--r-- | drivers/base/power/qos-test.c | 117 | ||||
| -rw-r--r-- | drivers/base/power/qos.c | 983 | ||||
| -rw-r--r-- | drivers/base/power/runtime-test.c | 249 | ||||
| -rw-r--r-- | drivers/base/power/runtime.c | 2118 | ||||
| -rw-r--r-- | drivers/base/power/sysfs.c | 835 | ||||
| -rw-r--r-- | drivers/base/power/trace.c | 305 | ||||
| -rw-r--r-- | drivers/base/power/wakeirq.c | 394 | ||||
| -rw-r--r-- | drivers/base/power/wakeup.c | 1245 | ||||
| -rw-r--r-- | drivers/base/power/wakeup_stats.c | 219 |
15 files changed, 10521 insertions, 0 deletions
diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile new file mode 100644 index 000000000..2989e42d0 --- /dev/null +++ b/drivers/base/power/Makefile @@ -0,0 +1,9 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_PM) += sysfs.o generic_ops.o common.o qos.o runtime.o wakeirq.o +obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o wakeup_stats.o +obj-$(CONFIG_PM_TRACE_RTC) += trace.o +obj-$(CONFIG_HAVE_CLK) += clock_ops.o +obj-$(CONFIG_PM_QOS_KUNIT_TEST) += qos-test.o +obj-$(CONFIG_PM_RUNTIME_KUNIT_TEST) += runtime-test.o + +ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c new file mode 100644 index 000000000..59bb37e82 --- /dev/null +++ b/drivers/base/power/clock_ops.c @@ -0,0 +1,732 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/clock_ops.c - Generic clock manipulation PM callbacks + * + * Copyright (c) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp. + */ + +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/io.h> +#include <linux/pm.h> +#include <linux/pm_clock.h> +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/of_clk.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/pm_domain.h> +#include <linux/pm_runtime.h> + +#ifdef CONFIG_PM_CLK + +enum pce_status { + PCE_STATUS_NONE = 0, + PCE_STATUS_ACQUIRED, + PCE_STATUS_PREPARED, + PCE_STATUS_ENABLED, + PCE_STATUS_ERROR, +}; + +struct pm_clock_entry { + struct list_head node; + char *con_id; + struct clk *clk; + enum pce_status status; + bool enabled_when_prepared; +}; + +/** + * pm_clk_list_lock - ensure exclusive access for modifying the PM clock + * entry list. + * @psd: pm_subsys_data instance corresponding to the PM clock entry list + * and clk_op_might_sleep count to be modified. + * + * Get exclusive access before modifying the PM clock entry list and the + * clock_op_might_sleep count to guard against concurrent modifications. + * This also protects against a concurrent clock_op_might_sleep and PM clock + * entry list usage in pm_clk_suspend()/pm_clk_resume() that may or may not + * happen in atomic context, hence both the mutex and the spinlock must be + * taken here. + */ +static void pm_clk_list_lock(struct pm_subsys_data *psd) + __acquires(&psd->lock) +{ + mutex_lock(&psd->clock_mutex); + spin_lock_irq(&psd->lock); +} + +/** + * pm_clk_list_unlock - counterpart to pm_clk_list_lock(). + * @psd: the same pm_subsys_data instance previously passed to + * pm_clk_list_lock(). + */ +static void pm_clk_list_unlock(struct pm_subsys_data *psd) + __releases(&psd->lock) +{ + spin_unlock_irq(&psd->lock); + mutex_unlock(&psd->clock_mutex); +} + +/** + * pm_clk_op_lock - ensure exclusive access for performing clock operations. + * @psd: pm_subsys_data instance corresponding to the PM clock entry list + * and clk_op_might_sleep count being used. + * @flags: stored irq flags. + * @fn: string for the caller function's name. + * + * This is used by pm_clk_suspend() and pm_clk_resume() to guard + * against concurrent modifications to the clock entry list and the + * clock_op_might_sleep count. If clock_op_might_sleep is != 0 then + * only the mutex can be locked and those functions can only be used in + * non atomic context. If clock_op_might_sleep == 0 then these functions + * may be used in any context and only the spinlock can be locked. + * Returns -EINVAL if called in atomic context when clock ops might sleep. + */ +static int pm_clk_op_lock(struct pm_subsys_data *psd, unsigned long *flags, + const char *fn) + /* sparse annotations don't work here as exit state isn't static */ +{ + bool atomic_context = in_atomic() || irqs_disabled(); + +try_again: + spin_lock_irqsave(&psd->lock, *flags); + if (!psd->clock_op_might_sleep) { + /* the __release is there to work around sparse limitations */ + __release(&psd->lock); + return 0; + } + + /* bail out if in atomic context */ + if (atomic_context) { + pr_err("%s: atomic context with clock_ops_might_sleep = %d", + fn, psd->clock_op_might_sleep); + spin_unlock_irqrestore(&psd->lock, *flags); + might_sleep(); + return -EPERM; + } + + /* we must switch to the mutex */ + spin_unlock_irqrestore(&psd->lock, *flags); + mutex_lock(&psd->clock_mutex); + + /* + * There was a possibility for psd->clock_op_might_sleep + * to become 0 above. Keep the mutex only if not the case. + */ + if (likely(psd->clock_op_might_sleep)) + return 0; + + mutex_unlock(&psd->clock_mutex); + goto try_again; +} + +/** + * pm_clk_op_unlock - counterpart to pm_clk_op_lock(). + * @psd: the same pm_subsys_data instance previously passed to + * pm_clk_op_lock(). + * @flags: irq flags provided by pm_clk_op_lock(). + */ +static void pm_clk_op_unlock(struct pm_subsys_data *psd, unsigned long *flags) + /* sparse annotations don't work here as entry state isn't static */ +{ + if (psd->clock_op_might_sleep) { + mutex_unlock(&psd->clock_mutex); + } else { + /* the __acquire is there to work around sparse limitations */ + __acquire(&psd->lock); + spin_unlock_irqrestore(&psd->lock, *flags); + } +} + +/** + * __pm_clk_enable - Enable a clock, reporting any errors + * @dev: The device for the given clock + * @ce: PM clock entry corresponding to the clock. + */ +static inline void __pm_clk_enable(struct device *dev, struct pm_clock_entry *ce) +{ + int ret; + + switch (ce->status) { + case PCE_STATUS_ACQUIRED: + ret = clk_prepare_enable(ce->clk); + break; + case PCE_STATUS_PREPARED: + ret = clk_enable(ce->clk); + break; + default: + return; + } + if (!ret) + ce->status = PCE_STATUS_ENABLED; + else + dev_err(dev, "%s: failed to enable clk %p, error %d\n", + __func__, ce->clk, ret); +} + +/** + * pm_clk_acquire - Acquire a device clock. + * @dev: Device whose clock is to be acquired. + * @ce: PM clock entry corresponding to the clock. + */ +static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) +{ + if (!ce->clk) + ce->clk = clk_get(dev, ce->con_id); + if (IS_ERR(ce->clk)) { + ce->status = PCE_STATUS_ERROR; + return; + } else if (clk_is_enabled_when_prepared(ce->clk)) { + /* we defer preparing the clock in that case */ + ce->status = PCE_STATUS_ACQUIRED; + ce->enabled_when_prepared = true; + } else if (clk_prepare(ce->clk)) { + ce->status = PCE_STATUS_ERROR; + dev_err(dev, "clk_prepare() failed\n"); + return; + } else { + ce->status = PCE_STATUS_PREPARED; + } + dev_dbg(dev, "Clock %pC con_id %s managed by runtime PM.\n", + ce->clk, ce->con_id); +} + +static int __pm_clk_add(struct device *dev, const char *con_id, + struct clk *clk) +{ + struct pm_subsys_data *psd = dev_to_psd(dev); + struct pm_clock_entry *ce; + + if (!psd) + return -EINVAL; + + ce = kzalloc_obj(*ce); + if (!ce) + return -ENOMEM; + + if (con_id) { + ce->con_id = kstrdup(con_id, GFP_KERNEL); + if (!ce->con_id) { + kfree(ce); + return -ENOMEM; + } + } else { + if (IS_ERR(clk)) { + kfree(ce); + return -ENOENT; + } + ce->clk = clk; + } + + pm_clk_acquire(dev, ce); + + pm_clk_list_lock(psd); + list_add_tail(&ce->node, &psd->clock_list); + if (ce->enabled_when_prepared) + psd->clock_op_might_sleep++; + pm_clk_list_unlock(psd); + return 0; +} + +/** + * pm_clk_add - Start using a device clock for power management. + * @dev: Device whose clock is going to be used for power management. + * @con_id: Connection ID of the clock. + * + * Add the clock represented by @con_id to the list of clocks used for + * the power management of @dev. + */ +int pm_clk_add(struct device *dev, const char *con_id) +{ + return __pm_clk_add(dev, con_id, NULL); +} +EXPORT_SYMBOL_GPL(pm_clk_add); + +/** + * pm_clk_add_clk - Start using a device clock for power management. + * @dev: Device whose clock is going to be used for power management. + * @clk: Clock pointer + * + * Add the clock to the list of clocks used for the power management of @dev. + * The power-management code will take control of the clock reference, so + * callers should not call clk_put() on @clk after this function sucessfully + * returned. + */ +int pm_clk_add_clk(struct device *dev, struct clk *clk) +{ + return __pm_clk_add(dev, NULL, clk); +} +EXPORT_SYMBOL_GPL(pm_clk_add_clk); + +/** + * of_pm_clk_add_clks - Start using device clock(s) for power management. + * @dev: Device whose clock(s) is going to be used for power management. + * + * Add a series of clocks described in the 'clocks' device-tree node for + * a device to the list of clocks used for the power management of @dev. + * On success, returns the number of clocks added. Returns a negative + * error code if there are no clocks in the device node for the device + * or if adding a clock fails. + */ +int of_pm_clk_add_clks(struct device *dev) +{ + struct clk **clks; + int i, count; + int ret; + + if (!dev || !dev->of_node) + return -EINVAL; + + count = of_clk_get_parent_count(dev->of_node); + if (count <= 0) + return -ENODEV; + + clks = kzalloc_objs(*clks, count); + if (!clks) + return -ENOMEM; + + for (i = 0; i < count; i++) { + clks[i] = of_clk_get(dev->of_node, i); + if (IS_ERR(clks[i])) { + ret = PTR_ERR(clks[i]); + goto error; + } + + ret = pm_clk_add_clk(dev, clks[i]); + if (ret) { + clk_put(clks[i]); + goto error; + } + } + + kfree(clks); + + return i; + +error: + while (i--) + pm_clk_remove_clk(dev, clks[i]); + + kfree(clks); + + return ret; +} +EXPORT_SYMBOL_GPL(of_pm_clk_add_clks); + +/** + * __pm_clk_remove - Destroy PM clock entry. + * @ce: PM clock entry to destroy. + */ +static void __pm_clk_remove(struct pm_clock_entry *ce) +{ + if (!ce) + return; + + switch (ce->status) { + case PCE_STATUS_ENABLED: + clk_disable(ce->clk); + fallthrough; + case PCE_STATUS_PREPARED: + clk_unprepare(ce->clk); + fallthrough; + case PCE_STATUS_ACQUIRED: + case PCE_STATUS_ERROR: + if (!IS_ERR(ce->clk)) + clk_put(ce->clk); + break; + default: + break; + } + + kfree(ce->con_id); + kfree(ce); +} + +/** + * pm_clk_remove_clk - Stop using a device clock for power management. + * @dev: Device whose clock should not be used for PM any more. + * @clk: Clock pointer + * + * Remove the clock pointed to by @clk from the list of clocks used for + * the power management of @dev. + */ +void pm_clk_remove_clk(struct device *dev, struct clk *clk) +{ + struct pm_subsys_data *psd = dev_to_psd(dev); + struct pm_clock_entry *ce; + + if (!psd || !clk) + return; + + pm_clk_list_lock(psd); + + list_for_each_entry(ce, &psd->clock_list, node) { + if (clk == ce->clk) + goto remove; + } + + pm_clk_list_unlock(psd); + return; + + remove: + list_del(&ce->node); + if (ce->enabled_when_prepared) + psd->clock_op_might_sleep--; + pm_clk_list_unlock(psd); + + __pm_clk_remove(ce); +} +EXPORT_SYMBOL_GPL(pm_clk_remove_clk); + +/** + * pm_clk_init - Initialize a device's list of power management clocks. + * @dev: Device to initialize the list of PM clocks for. + * + * Initialize the lock and clock_list members of the device's pm_subsys_data + * object, set the count of clocks that might sleep to 0. + */ +void pm_clk_init(struct device *dev) +{ + struct pm_subsys_data *psd = dev_to_psd(dev); + if (psd) { + INIT_LIST_HEAD(&psd->clock_list); + mutex_init(&psd->clock_mutex); + psd->clock_op_might_sleep = 0; + } +} +EXPORT_SYMBOL_GPL(pm_clk_init); + +/** + * pm_clk_create - Create and initialize a device's list of PM clocks. + * @dev: Device to create and initialize the list of PM clocks for. + * + * Allocate a struct pm_subsys_data object, initialize its lock and clock_list + * members and make the @dev's power.subsys_data field point to it. + */ +int pm_clk_create(struct device *dev) +{ + return dev_pm_get_subsys_data(dev); +} +EXPORT_SYMBOL_GPL(pm_clk_create); + +/** + * pm_clk_destroy - Destroy a device's list of power management clocks. + * @dev: Device to destroy the list of PM clocks for. + * + * Clear the @dev's power.subsys_data field, remove the list of clock entries + * from the struct pm_subsys_data object pointed to by it before and free + * that object. + */ +void pm_clk_destroy(struct device *dev) +{ + struct pm_subsys_data *psd = dev_to_psd(dev); + struct pm_clock_entry *ce, *c; + struct list_head list; + + if (!psd) + return; + + INIT_LIST_HEAD(&list); + + pm_clk_list_lock(psd); + + list_for_each_entry_safe_reverse(ce, c, &psd->clock_list, node) + list_move(&ce->node, &list); + psd->clock_op_might_sleep = 0; + + pm_clk_list_unlock(psd); + + dev_pm_put_subsys_data(dev); + + list_for_each_entry_safe_reverse(ce, c, &list, node) { + list_del(&ce->node); + __pm_clk_remove(ce); + } +} +EXPORT_SYMBOL_GPL(pm_clk_destroy); + +static void pm_clk_destroy_action(void *data) +{ + pm_clk_destroy(data); +} + +int devm_pm_clk_create(struct device *dev) +{ + int ret; + + ret = pm_clk_create(dev); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, pm_clk_destroy_action, dev); +} +EXPORT_SYMBOL_GPL(devm_pm_clk_create); + +/** + * pm_clk_suspend - Disable clocks in a device's PM clock list. + * @dev: Device to disable the clocks for. + */ +int pm_clk_suspend(struct device *dev) +{ + struct pm_subsys_data *psd = dev_to_psd(dev); + struct pm_clock_entry *ce; + unsigned long flags; + int ret; + + dev_dbg(dev, "%s()\n", __func__); + + if (!psd) + return 0; + + ret = pm_clk_op_lock(psd, &flags, __func__); + if (ret) + return ret; + + list_for_each_entry_reverse(ce, &psd->clock_list, node) { + if (ce->status == PCE_STATUS_ENABLED) { + if (ce->enabled_when_prepared) { + clk_disable_unprepare(ce->clk); + ce->status = PCE_STATUS_ACQUIRED; + } else { + clk_disable(ce->clk); + ce->status = PCE_STATUS_PREPARED; + } + } + } + + pm_clk_op_unlock(psd, &flags); + + return 0; +} +EXPORT_SYMBOL_GPL(pm_clk_suspend); + +/** + * pm_clk_resume - Enable clocks in a device's PM clock list. + * @dev: Device to enable the clocks for. + */ +int pm_clk_resume(struct device *dev) +{ + struct pm_subsys_data *psd = dev_to_psd(dev); + struct pm_clock_entry *ce; + unsigned long flags; + int ret; + + dev_dbg(dev, "%s()\n", __func__); + + if (!psd) + return 0; + + ret = pm_clk_op_lock(psd, &flags, __func__); + if (ret) + return ret; + + list_for_each_entry(ce, &psd->clock_list, node) + __pm_clk_enable(dev, ce); + + pm_clk_op_unlock(psd, &flags); + + return 0; +} +EXPORT_SYMBOL_GPL(pm_clk_resume); + +/** + * pm_clk_notify - Notify routine for device addition and removal. + * @nb: Notifier block object this function is a member of. + * @action: Operation being carried out by the caller. + * @data: Device the routine is being run for. + * + * For this function to work, @nb must be a member of an object of type + * struct pm_clk_notifier_block containing all of the requisite data. + * Specifically, the pm_domain member of that object is copied to the device's + * pm_domain field and its con_ids member is used to populate the device's list + * of PM clocks, depending on @action. + * + * If the device's pm_domain field is already populated with a value different + * from the one stored in the struct pm_clk_notifier_block object, the function + * does nothing. + */ +static int pm_clk_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct pm_clk_notifier_block *clknb; + struct device *dev = data; + char **con_id; + int error; + + dev_dbg(dev, "%s() %ld\n", __func__, action); + + clknb = container_of(nb, struct pm_clk_notifier_block, nb); + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + if (dev->pm_domain) + break; + + error = pm_clk_create(dev); + if (error) + break; + + dev_pm_domain_set(dev, clknb->pm_domain); + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids; *con_id; con_id++) + pm_clk_add(dev, *con_id); + } else { + pm_clk_add(dev, NULL); + } + + break; + case BUS_NOTIFY_DEL_DEVICE: + if (dev->pm_domain != clknb->pm_domain) + break; + + dev_pm_domain_set(dev, NULL); + pm_clk_destroy(dev); + break; + } + + return 0; +} + +int pm_clk_runtime_suspend(struct device *dev) +{ + int ret; + + dev_dbg(dev, "%s\n", __func__); + + ret = pm_generic_runtime_suspend(dev); + if (ret) { + dev_err(dev, "failed to suspend device\n"); + return ret; + } + + ret = pm_clk_suspend(dev); + if (ret) { + dev_err(dev, "failed to suspend clock\n"); + pm_generic_runtime_resume(dev); + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(pm_clk_runtime_suspend); + +int pm_clk_runtime_resume(struct device *dev) +{ + int ret; + + dev_dbg(dev, "%s\n", __func__); + + ret = pm_clk_resume(dev); + if (ret) { + dev_err(dev, "failed to resume clock\n"); + return ret; + } + + return pm_generic_runtime_resume(dev); +} +EXPORT_SYMBOL_GPL(pm_clk_runtime_resume); + +#else /* !CONFIG_PM_CLK */ + +/** + * enable_clock - Enable a device clock. + * @dev: Device whose clock is to be enabled. + * @con_id: Connection ID of the clock. + */ +static void enable_clock(struct device *dev, const char *con_id) +{ + struct clk *clk; + + clk = clk_get(dev, con_id); + if (!IS_ERR(clk)) { + clk_prepare_enable(clk); + clk_put(clk); + dev_info(dev, "Runtime PM disabled, clock forced on.\n"); + } +} + +/** + * disable_clock - Disable a device clock. + * @dev: Device whose clock is to be disabled. + * @con_id: Connection ID of the clock. + */ +static void disable_clock(struct device *dev, const char *con_id) +{ + struct clk *clk; + + clk = clk_get(dev, con_id); + if (!IS_ERR(clk)) { + clk_disable_unprepare(clk); + clk_put(clk); + dev_info(dev, "Runtime PM disabled, clock forced off.\n"); + } +} + +/** + * pm_clk_notify - Notify routine for device addition and removal. + * @nb: Notifier block object this function is a member of. + * @action: Operation being carried out by the caller. + * @data: Device the routine is being run for. + * + * For this function to work, @nb must be a member of an object of type + * struct pm_clk_notifier_block containing all of the requisite data. + * Specifically, the con_ids member of that object is used to enable or disable + * the device's clocks, depending on @action. + */ +static int pm_clk_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct pm_clk_notifier_block *clknb; + struct device *dev = data; + char **con_id; + + dev_dbg(dev, "%s() %ld\n", __func__, action); + + clknb = container_of(nb, struct pm_clk_notifier_block, nb); + + switch (action) { + case BUS_NOTIFY_BIND_DRIVER: + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids; *con_id; con_id++) + enable_clock(dev, *con_id); + } else { + enable_clock(dev, NULL); + } + break; + case BUS_NOTIFY_DRIVER_NOT_BOUND: + case BUS_NOTIFY_UNBOUND_DRIVER: + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids; *con_id; con_id++) + disable_clock(dev, *con_id); + } else { + disable_clock(dev, NULL); + } + break; + } + + return 0; +} + +#endif /* !CONFIG_PM_CLK */ + +/** + * pm_clk_add_notifier - Add bus type notifier for power management clocks. + * @bus: Bus type to add the notifier to. + * @clknb: Notifier to be added to the given bus type. + * + * The nb member of @clknb is not expected to be initialized and its + * notifier_call member will be replaced with pm_clk_notify(). However, + * the remaining members of @clknb should be populated prior to calling this + * routine. + */ +void pm_clk_add_notifier(const struct bus_type *bus, + struct pm_clk_notifier_block *clknb) +{ + if (!bus || !clknb) + return; + + clknb->nb.notifier_call = pm_clk_notify; + bus_register_notifier(bus, &clknb->nb); +} +EXPORT_SYMBOL_GPL(pm_clk_add_notifier); diff --git a/drivers/base/power/common.c b/drivers/base/power/common.c new file mode 100644 index 000000000..9bef9248a --- /dev/null +++ b/drivers/base/power/common.c @@ -0,0 +1,457 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/common.c - Common device power management code. + * + * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp. + */ +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/pm_clock.h> +#include <linux/acpi.h> +#include <linux/pm_domain.h> +#include <linux/pm_opp.h> + +#include "power.h" + +/** + * dev_pm_get_subsys_data - Create or refcount power.subsys_data for device. + * @dev: Device to handle. + * + * If power.subsys_data is NULL, point it to a new object, otherwise increment + * its reference counter. Return 0 if new object has been created or refcount + * increased, otherwise negative error code. + */ +int dev_pm_get_subsys_data(struct device *dev) +{ + struct pm_subsys_data *psd; + + psd = kzalloc_obj(*psd); + if (!psd) + return -ENOMEM; + + spin_lock_irq(&dev->power.lock); + + if (dev->power.subsys_data) { + dev->power.subsys_data->refcount++; + } else { + spin_lock_init(&psd->lock); + psd->refcount = 1; + dev->power.subsys_data = psd; + pm_clk_init(dev); + psd = NULL; + } + + spin_unlock_irq(&dev->power.lock); + + /* kfree() verifies that its argument is nonzero. */ + kfree(psd); + + return 0; +} +EXPORT_SYMBOL_GPL(dev_pm_get_subsys_data); + +/** + * dev_pm_put_subsys_data - Drop reference to power.subsys_data. + * @dev: Device to handle. + * + * If the reference counter of power.subsys_data is zero after dropping the + * reference, power.subsys_data is removed. + */ +void dev_pm_put_subsys_data(struct device *dev) +{ + struct pm_subsys_data *psd; + + spin_lock_irq(&dev->power.lock); + + psd = dev_to_psd(dev); + if (!psd) + goto out; + + if (--psd->refcount == 0) + dev->power.subsys_data = NULL; + else + psd = NULL; + + out: + spin_unlock_irq(&dev->power.lock); + kfree(psd); +} +EXPORT_SYMBOL_GPL(dev_pm_put_subsys_data); + +/** + * dev_pm_domain_attach - Attach a device to its PM domain. + * @dev: Device to attach. + * @flags: indicate whether we should power on/off the device on attach/detach + * + * The @dev may only be attached to a single PM domain. By iterating through + * the available alternatives we try to find a valid PM domain for the device. + * As attachment succeeds, the ->detach() callback in the struct dev_pm_domain + * should be assigned by the corresponding attach function. + * + * This function should typically be invoked from subsystem level code during + * the probe phase. Especially for those that holds devices which requires + * power management through PM domains. + * + * Callers must ensure proper synchronization of this function with power + * management callbacks. + * + * Returns 0 on successfully attached PM domain, or when it is found that the + * device doesn't need a PM domain, else a negative error code. + */ +int dev_pm_domain_attach(struct device *dev, u32 flags) +{ + int ret; + + if (dev->pm_domain) + return 0; + + ret = acpi_dev_pm_attach(dev, !!(flags & PD_FLAG_ATTACH_POWER_ON)); + if (!ret) + ret = genpd_dev_pm_attach(dev); + + if (dev->pm_domain) + dev->power.detach_power_off = !!(flags & PD_FLAG_DETACH_POWER_OFF); + + return ret < 0 ? ret : 0; +} +EXPORT_SYMBOL_GPL(dev_pm_domain_attach); + +/** + * dev_pm_domain_attach_by_id - Associate a device with one of its PM domains. + * @dev: The device used to lookup the PM domain. + * @index: The index of the PM domain. + * + * As @dev may only be attached to a single PM domain, the backend PM domain + * provider creates a virtual device to attach instead. If attachment succeeds, + * the ->detach() callback in the struct dev_pm_domain are assigned by the + * corresponding backend attach function, as to deal with detaching of the + * created virtual device. + * + * This function should typically be invoked by a driver during the probe phase, + * in case its device requires power management through multiple PM domains. The + * driver may benefit from using the received device, to configure device-links + * towards its original device. Depending on the use-case and if needed, the + * links may be dynamically changed by the driver, which allows it to control + * the power to the PM domains independently from each other. + * + * Callers must ensure proper synchronization of this function with power + * management callbacks. + * + * Returns the virtual created device when successfully attached to its PM + * domain, NULL in case @dev don't need a PM domain, else an ERR_PTR(). + * Note that, to detach the returned virtual device, the driver shall call + * dev_pm_domain_detach() on it, typically during the remove phase. + */ +struct device *dev_pm_domain_attach_by_id(struct device *dev, + unsigned int index) +{ + if (dev->pm_domain) + return ERR_PTR(-EEXIST); + + return genpd_dev_pm_attach_by_id(dev, index); +} +EXPORT_SYMBOL_GPL(dev_pm_domain_attach_by_id); + +/** + * dev_pm_domain_attach_by_name - Associate a device with one of its PM domains. + * @dev: The device used to lookup the PM domain. + * @name: The name of the PM domain. + * + * For a detailed function description, see dev_pm_domain_attach_by_id(). + */ +struct device *dev_pm_domain_attach_by_name(struct device *dev, + const char *name) +{ + if (dev->pm_domain) + return ERR_PTR(-EEXIST); + + return genpd_dev_pm_attach_by_name(dev, name); +} +EXPORT_SYMBOL_GPL(dev_pm_domain_attach_by_name); + +/** + * dev_pm_domain_attach_list - Associate a device with its PM domains. + * @dev: The device used to lookup the PM domains for. + * @data: The data used for attaching to the PM domains. + * @list: An out-parameter with an allocated list of attached PM domains. + * + * This function helps to attach a device to its multiple PM domains. The + * caller, which is typically a driver's probe function, may provide a list of + * names for the PM domains that we should try to attach the device to, but it + * may also provide an empty list, in case the attach should be done for all of + * the available PM domains. + * + * Callers must ensure proper synchronization of this function with power + * management callbacks. + * + * Returns the number of attached PM domains or a negative error code in case of + * a failure. Note that, to detach the list of PM domains, the driver shall call + * dev_pm_domain_detach_list(), typically during the remove phase. + */ +int dev_pm_domain_attach_list(struct device *dev, + const struct dev_pm_domain_attach_data *data, + struct dev_pm_domain_list **list) +{ + struct device_node *np = dev->of_node; + struct dev_pm_domain_list *pds; + struct device *pd_dev = NULL; + int ret, i, num_pds = 0; + bool by_id = true; + size_t size; + u32 pd_flags = data ? data->pd_flags : 0; + u32 link_flags = pd_flags & PD_FLAG_NO_DEV_LINK ? 0 : + DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME; + + if (dev->pm_domain) + return -EEXIST; + + /* For now this is limited to OF based platforms. */ + if (!np) + return 0; + + if (data && data->pd_names) { + num_pds = data->num_pd_names; + by_id = false; + } else { + num_pds = of_count_phandle_with_args(np, "power-domains", + "#power-domain-cells"); + } + + if (num_pds <= 0) + return 0; + + pds = kzalloc_obj(*pds); + if (!pds) + return -ENOMEM; + + size = sizeof(*pds->pd_devs) + sizeof(*pds->pd_links) + + sizeof(*pds->opp_tokens); + pds->pd_devs = kcalloc(num_pds, size, GFP_KERNEL); + if (!pds->pd_devs) { + ret = -ENOMEM; + goto free_pds; + } + pds->pd_links = (void *)(pds->pd_devs + num_pds); + pds->opp_tokens = (void *)(pds->pd_links + num_pds); + + if (link_flags && pd_flags & PD_FLAG_DEV_LINK_ON) + link_flags |= DL_FLAG_RPM_ACTIVE; + + for (i = 0; i < num_pds; i++) { + if (by_id) + pd_dev = dev_pm_domain_attach_by_id(dev, i); + else + pd_dev = dev_pm_domain_attach_by_name(dev, + data->pd_names[i]); + if (IS_ERR_OR_NULL(pd_dev)) { + ret = pd_dev ? PTR_ERR(pd_dev) : -ENODEV; + goto err_attach; + } + + if (pd_flags & PD_FLAG_REQUIRED_OPP) { + struct dev_pm_opp_config config = { + .required_dev = pd_dev, + .required_dev_index = i, + }; + + ret = dev_pm_opp_set_config(dev, &config); + if (ret < 0) + goto err_link; + + pds->opp_tokens[i] = ret; + } + + if (link_flags) { + struct device_link *link; + + link = device_link_add(dev, pd_dev, link_flags); + if (!link) { + ret = -ENODEV; + goto err_link; + } + + pds->pd_links[i] = link; + } + + pds->pd_devs[i] = pd_dev; + } + + pds->num_pds = num_pds; + *list = pds; + return num_pds; + +err_link: + dev_pm_opp_clear_config(pds->opp_tokens[i]); + dev_pm_domain_detach(pd_dev, true); +err_attach: + while (--i >= 0) { + dev_pm_opp_clear_config(pds->opp_tokens[i]); + if (pds->pd_links[i]) + device_link_del(pds->pd_links[i]); + dev_pm_domain_detach(pds->pd_devs[i], true); + } + kfree(pds->pd_devs); +free_pds: + kfree(pds); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_domain_attach_list); + +/** + * devm_pm_domain_detach_list - devres-enabled version of dev_pm_domain_detach_list. + * @_list: The list of PM domains to detach. + * + * This function reverse the actions from devm_pm_domain_attach_list(). + * it will be invoked during the remove phase from drivers implicitly if driver + * uses devm_pm_domain_attach_list() to attach the PM domains. + */ +static void devm_pm_domain_detach_list(void *_list) +{ + struct dev_pm_domain_list *list = _list; + + dev_pm_domain_detach_list(list); +} + +/** + * devm_pm_domain_attach_list - devres-enabled version of dev_pm_domain_attach_list + * @dev: The device used to lookup the PM domains for. + * @data: The data used for attaching to the PM domains. + * @list: An out-parameter with an allocated list of attached PM domains. + * + * NOTE: this will also handle calling devm_pm_domain_detach_list() for + * you during remove phase. + * + * Returns the number of attached PM domains or a negative error code in case of + * a failure. + */ +int devm_pm_domain_attach_list(struct device *dev, + const struct dev_pm_domain_attach_data *data, + struct dev_pm_domain_list **list) +{ + int ret, num_pds; + + num_pds = dev_pm_domain_attach_list(dev, data, list); + if (num_pds <= 0) + return num_pds; + + ret = devm_add_action_or_reset(dev, devm_pm_domain_detach_list, *list); + if (ret) + return ret; + + return num_pds; +} +EXPORT_SYMBOL_GPL(devm_pm_domain_attach_list); + +/** + * dev_pm_domain_detach - Detach a device from its PM domain. + * @dev: Device to detach. + * @power_off: Used to indicate whether we should power off the device. + * + * This functions will reverse the actions from dev_pm_domain_attach(), + * dev_pm_domain_attach_by_id() and dev_pm_domain_attach_by_name(), thus it + * detaches @dev from its PM domain. Typically it should be invoked during the + * remove phase, either from subsystem level code or from drivers. + * + * Callers must ensure proper synchronization of this function with power + * management callbacks. + */ +void dev_pm_domain_detach(struct device *dev, bool power_off) +{ + if (dev->pm_domain && dev->pm_domain->detach) + dev->pm_domain->detach(dev, power_off); +} +EXPORT_SYMBOL_GPL(dev_pm_domain_detach); + +/** + * dev_pm_domain_detach_list - Detach a list of PM domains. + * @list: The list of PM domains to detach. + * + * This function reverse the actions from dev_pm_domain_attach_list(). + * Typically it should be invoked during the remove phase from drivers. + * + * Callers must ensure proper synchronization of this function with power + * management callbacks. + */ +void dev_pm_domain_detach_list(struct dev_pm_domain_list *list) +{ + int i; + + if (!list) + return; + + for (i = 0; i < list->num_pds; i++) { + dev_pm_opp_clear_config(list->opp_tokens[i]); + if (list->pd_links[i]) + device_link_del(list->pd_links[i]); + dev_pm_domain_detach(list->pd_devs[i], true); + } + + kfree(list->pd_devs); + kfree(list); +} +EXPORT_SYMBOL_GPL(dev_pm_domain_detach_list); + +/** + * dev_pm_domain_start - Start the device through its PM domain. + * @dev: Device to start. + * + * This function should typically be called during probe by a subsystem/driver, + * when it needs to start its device from the PM domain's perspective. Note + * that, it's assumed that the PM domain is already powered on when this + * function is called. + * + * Returns 0 on success and negative error values on failures. + */ +int dev_pm_domain_start(struct device *dev) +{ + if (dev->pm_domain && dev->pm_domain->start) + return dev->pm_domain->start(dev); + + return 0; +} +EXPORT_SYMBOL_GPL(dev_pm_domain_start); + +/** + * dev_pm_domain_set - Set PM domain of a device. + * @dev: Device whose PM domain is to be set. + * @pd: PM domain to be set, or NULL. + * + * Sets the PM domain the device belongs to. The PM domain of a device needs + * to be set before its probe finishes (it's bound to a driver). + * + * This function must be called with the device lock held. + */ +void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd) +{ + if (dev->pm_domain == pd) + return; + + WARN(pd && device_is_bound(dev), + "PM domains can only be changed for unbound devices\n"); + dev->pm_domain = pd; + device_pm_check_callbacks(dev); +} +EXPORT_SYMBOL_GPL(dev_pm_domain_set); + +/** + * dev_pm_domain_set_performance_state - Request a new performance state. + * @dev: The device to make the request for. + * @state: Target performance state for the device. + * + * This function should be called when a new performance state needs to be + * requested for a device that is attached to a PM domain. Note that, the + * support for performance scaling for PM domains is optional. + * + * Returns 0 on success and when performance scaling isn't supported, negative + * error code on failure. + */ +int dev_pm_domain_set_performance_state(struct device *dev, unsigned int state) +{ + if (dev->pm_domain && dev->pm_domain->set_performance_state) + return dev->pm_domain->set_performance_state(dev, state); + + return 0; +} +EXPORT_SYMBOL_GPL(dev_pm_domain_set_performance_state); diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c new file mode 100644 index 000000000..af99bbcf2 --- /dev/null +++ b/drivers/base/power/generic_ops.c @@ -0,0 +1,239 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/generic_ops.c - Generic PM callbacks for subsystems + * + * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + */ +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/export.h> + +#define CALL_PM_OP(dev, op) \ +({ \ + struct device *_dev = (dev); \ + const struct dev_pm_ops *pm = _dev->driver ? _dev->driver->pm : NULL; \ + pm && pm->op ? pm->op(_dev) : 0; \ +}) + +#ifdef CONFIG_PM +/** + * pm_generic_runtime_suspend - Generic runtime suspend callback for subsystems. + * @dev: Device to suspend. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_suspend(), execute it and return its error code. Otherwise, + * return 0. + */ +int pm_generic_runtime_suspend(struct device *dev) +{ + return CALL_PM_OP(dev, runtime_suspend); +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_suspend); + +/** + * pm_generic_runtime_resume - Generic runtime resume callback for subsystems. + * @dev: Device to resume. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_resume(), execute it and return its error code. Otherwise, + * return 0. + */ +int pm_generic_runtime_resume(struct device *dev) +{ + return CALL_PM_OP(dev, runtime_resume); +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_resume); +#endif /* CONFIG_PM */ + +#ifdef CONFIG_PM_SLEEP +/** + * pm_generic_prepare - Generic routine preparing a device for power transition. + * @dev: Device to prepare. + * + * Prepare a device for a system-wide power transition. + */ +int pm_generic_prepare(struct device *dev) +{ + struct device_driver *drv = dev->driver; + int ret = 0; + + if (drv && drv->pm && drv->pm->prepare) + ret = drv->pm->prepare(dev); + + return ret; +} + +/** + * pm_generic_suspend_noirq - Generic suspend_noirq callback for subsystems. + * @dev: Device to suspend. + */ +int pm_generic_suspend_noirq(struct device *dev) +{ + return CALL_PM_OP(dev, suspend_noirq); +} +EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq); + +/** + * pm_generic_suspend_late - Generic suspend_late callback for subsystems. + * @dev: Device to suspend. + */ +int pm_generic_suspend_late(struct device *dev) +{ + return CALL_PM_OP(dev, suspend_late); +} +EXPORT_SYMBOL_GPL(pm_generic_suspend_late); + +/** + * pm_generic_suspend - Generic suspend callback for subsystems. + * @dev: Device to suspend. + */ +int pm_generic_suspend(struct device *dev) +{ + return CALL_PM_OP(dev, suspend); +} +EXPORT_SYMBOL_GPL(pm_generic_suspend); + +/** + * pm_generic_freeze_noirq - Generic freeze_noirq callback for subsystems. + * @dev: Device to freeze. + */ +int pm_generic_freeze_noirq(struct device *dev) +{ + return CALL_PM_OP(dev, freeze_noirq); +} +EXPORT_SYMBOL_GPL(pm_generic_freeze_noirq); + +/** + * pm_generic_freeze - Generic freeze callback for subsystems. + * @dev: Device to freeze. + */ +int pm_generic_freeze(struct device *dev) +{ + return CALL_PM_OP(dev, freeze); +} +EXPORT_SYMBOL_GPL(pm_generic_freeze); + +/** + * pm_generic_poweroff_noirq - Generic poweroff_noirq callback for subsystems. + * @dev: Device to handle. + */ +int pm_generic_poweroff_noirq(struct device *dev) +{ + return CALL_PM_OP(dev, poweroff_noirq); +} +EXPORT_SYMBOL_GPL(pm_generic_poweroff_noirq); + +/** + * pm_generic_poweroff_late - Generic poweroff_late callback for subsystems. + * @dev: Device to handle. + */ +int pm_generic_poweroff_late(struct device *dev) +{ + return CALL_PM_OP(dev, poweroff_late); +} +EXPORT_SYMBOL_GPL(pm_generic_poweroff_late); + +/** + * pm_generic_poweroff - Generic poweroff callback for subsystems. + * @dev: Device to handle. + */ +int pm_generic_poweroff(struct device *dev) +{ + return CALL_PM_OP(dev, poweroff); +} +EXPORT_SYMBOL_GPL(pm_generic_poweroff); + +/** + * pm_generic_thaw_noirq - Generic thaw_noirq callback for subsystems. + * @dev: Device to thaw. + */ +int pm_generic_thaw_noirq(struct device *dev) +{ + return CALL_PM_OP(dev, thaw_noirq); +} +EXPORT_SYMBOL_GPL(pm_generic_thaw_noirq); + +/** + * pm_generic_thaw - Generic thaw callback for subsystems. + * @dev: Device to thaw. + */ +int pm_generic_thaw(struct device *dev) +{ + return CALL_PM_OP(dev, thaw); +} +EXPORT_SYMBOL_GPL(pm_generic_thaw); + +/** + * pm_generic_resume_noirq - Generic resume_noirq callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_resume_noirq(struct device *dev) +{ + return CALL_PM_OP(dev, resume_noirq); +} +EXPORT_SYMBOL_GPL(pm_generic_resume_noirq); + +/** + * pm_generic_resume_early - Generic resume_early callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_resume_early(struct device *dev) +{ + return CALL_PM_OP(dev, resume_early); +} +EXPORT_SYMBOL_GPL(pm_generic_resume_early); + +/** + * pm_generic_resume - Generic resume callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_resume(struct device *dev) +{ + return CALL_PM_OP(dev, resume); +} +EXPORT_SYMBOL_GPL(pm_generic_resume); + +/** + * pm_generic_restore_noirq - Generic restore_noirq callback for subsystems. + * @dev: Device to restore. + */ +int pm_generic_restore_noirq(struct device *dev) +{ + return CALL_PM_OP(dev, restore_noirq); +} +EXPORT_SYMBOL_GPL(pm_generic_restore_noirq); + +/** + * pm_generic_restore_early - Generic restore_early callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_restore_early(struct device *dev) +{ + return CALL_PM_OP(dev, restore_early); +} +EXPORT_SYMBOL_GPL(pm_generic_restore_early); + +/** + * pm_generic_restore - Generic restore callback for subsystems. + * @dev: Device to restore. + */ +int pm_generic_restore(struct device *dev) +{ + return CALL_PM_OP(dev, restore); +} +EXPORT_SYMBOL_GPL(pm_generic_restore); + +/** + * pm_generic_complete - Generic routine completing a device power transition. + * @dev: Device to handle. + * + * Complete a device power transition during a system-wide power transition. + */ +void pm_generic_complete(struct device *dev) +{ + struct device_driver *drv = dev->driver; + + if (drv && drv->pm && drv->pm->complete) + drv->pm->complete(dev); +} +#endif /* CONFIG_PM_SLEEP */ diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c new file mode 100644 index 000000000..e130da428 --- /dev/null +++ b/drivers/base/power/main.c @@ -0,0 +1,2442 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/main.c - Where the driver meets power management. + * + * Copyright (c) 2003 Patrick Mochel + * Copyright (c) 2003 Open Source Development Lab + * + * The driver model core calls device_pm_add() when a device is registered. + * This will initialize the embedded device_pm_info object in the device + * and add it to the list of power-controlled devices. sysfs entries for + * controlling device power management will also be added. + * + * A separate list is used for keeping track of power info, because the power + * domain dependencies may differ from the ancestral dependencies that the + * subsystem list maintains. + */ + +#define pr_fmt(fmt) "PM: " fmt +#define dev_fmt pr_fmt + +#include <linux/device.h> +#include <linux/export.h> +#include <linux/mutex.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/pm-trace.h> +#include <linux/pm_wakeirq.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <linux/sched/debug.h> +#include <linux/sysctl.h> +#include <linux/async.h> +#include <linux/suspend.h> +#include <trace/events/power.h> +#include <linux/cpufreq.h> +#include <linux/devfreq.h> +#include <linux/thermal.h> +#include <linux/timer.h> +#include <linux/nmi.h> + +#include "../base.h" +#include "power.h" + +#undef MODULE_PARAM_PREFIX +#define MODULE_PARAM_PREFIX "pm." + +typedef int (*pm_callback_t)(struct device *); + +/* + * The entries in the dpm_list list are in a depth first order, simply + * because children are guaranteed to be discovered after parents, and + * are inserted at the back of the list on discovery. + * + * Since device_pm_add() may be called with a device lock held, + * we must never try to acquire a device lock while holding + * dpm_list_mutex. + */ + +LIST_HEAD(dpm_list); +static LIST_HEAD(dpm_prepared_list); +static LIST_HEAD(dpm_suspended_list); +static LIST_HEAD(dpm_late_early_list); +static LIST_HEAD(dpm_noirq_list); + +static DEFINE_MUTEX(dpm_list_mtx); +static pm_message_t pm_transition; + +static DEFINE_MUTEX(async_wip_mtx); +static int async_error; + +/** + * pm_hibernate_is_recovering - if recovering from hibernate due to error. + * + * Used to query if dev_pm_ops.thaw() is called for normal hibernation case or + * recovering from some error. + * + * Return: true for error case, false for normal case. + */ +bool pm_hibernate_is_recovering(void) +{ + return pm_transition.event == PM_EVENT_RECOVER; +} +EXPORT_SYMBOL_GPL(pm_hibernate_is_recovering); + +static const char *pm_verb(int event) +{ + switch (event) { + case PM_EVENT_SUSPEND: + return "suspend"; + case PM_EVENT_RESUME: + return "resume"; + case PM_EVENT_FREEZE: + return "freeze"; + case PM_EVENT_QUIESCE: + return "quiesce"; + case PM_EVENT_HIBERNATE: + return "hibernate"; + case PM_EVENT_THAW: + return "thaw"; + case PM_EVENT_RESTORE: + return "restore"; + case PM_EVENT_RECOVER: + return "recover"; + case PM_EVENT_POWEROFF: + return "poweroff"; + default: + return "(unknown PM event)"; + } +} + +/** + * device_pm_sleep_init - Initialize system suspend-related device fields. + * @dev: Device object being initialized. + */ +void device_pm_sleep_init(struct device *dev) +{ + dev->power.is_prepared = false; + dev->power.is_suspended = false; + dev->power.is_noirq_suspended = false; + dev->power.is_late_suspended = false; + init_completion(&dev->power.completion); + complete(&dev->power.completion); + dev->power.wakeup = NULL; + INIT_LIST_HEAD(&dev->power.entry); +} + +/** + * device_pm_lock - Lock the list of active devices used by the PM core. + */ +void device_pm_lock(void) +{ + mutex_lock(&dpm_list_mtx); +} + +/** + * device_pm_unlock - Unlock the list of active devices used by the PM core. + */ +void device_pm_unlock(void) +{ + mutex_unlock(&dpm_list_mtx); +} + +/** + * device_pm_add - Add a device to the PM core's list of active devices. + * @dev: Device to add to the list. + */ +void device_pm_add(struct device *dev) +{ + /* Skip PM setup/initialization. */ + if (device_pm_not_required(dev)) + return; + + pr_debug("Adding info for %s:%s\n", + dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); + device_pm_check_callbacks(dev); + mutex_lock(&dpm_list_mtx); + if (dev->parent && dev->parent->power.is_prepared) + dev_warn(dev, "parent %s should not be sleeping\n", + dev_name(dev->parent)); + list_add_tail(&dev->power.entry, &dpm_list); + dev->power.in_dpm_list = true; + mutex_unlock(&dpm_list_mtx); +} + +/** + * device_pm_remove - Remove a device from the PM core's list of active devices. + * @dev: Device to be removed from the list. + */ +void device_pm_remove(struct device *dev) +{ + if (device_pm_not_required(dev)) + return; + + pr_debug("Removing info for %s:%s\n", + dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); + complete_all(&dev->power.completion); + mutex_lock(&dpm_list_mtx); + list_del_init(&dev->power.entry); + dev->power.in_dpm_list = false; + mutex_unlock(&dpm_list_mtx); + device_wakeup_disable(dev); + pm_runtime_remove(dev); + device_pm_check_callbacks(dev); +} + +/** + * device_pm_move_before - Move device in the PM core's list of active devices. + * @deva: Device to move in dpm_list. + * @devb: Device @deva should come before. + */ +void device_pm_move_before(struct device *deva, struct device *devb) +{ + pr_debug("Moving %s:%s before %s:%s\n", + deva->bus ? deva->bus->name : "No Bus", dev_name(deva), + devb->bus ? devb->bus->name : "No Bus", dev_name(devb)); + /* Delete deva from dpm_list and reinsert before devb. */ + list_move_tail(&deva->power.entry, &devb->power.entry); +} + +/** + * device_pm_move_after - Move device in the PM core's list of active devices. + * @deva: Device to move in dpm_list. + * @devb: Device @deva should come after. + */ +void device_pm_move_after(struct device *deva, struct device *devb) +{ + pr_debug("Moving %s:%s after %s:%s\n", + deva->bus ? deva->bus->name : "No Bus", dev_name(deva), + devb->bus ? devb->bus->name : "No Bus", dev_name(devb)); + /* Delete deva from dpm_list and reinsert after devb. */ + list_move(&deva->power.entry, &devb->power.entry); +} + +/** + * device_pm_move_last - Move device to end of the PM core's list of devices. + * @dev: Device to move in dpm_list. + */ +void device_pm_move_last(struct device *dev) +{ + pr_debug("Moving %s:%s to end of list\n", + dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); + list_move_tail(&dev->power.entry, &dpm_list); +} + +static ktime_t initcall_debug_start(struct device *dev, void *cb) +{ + if (!pm_print_times_enabled) + return 0; + + dev_info(dev, "calling %ps @ %i, parent: %s\n", cb, + task_pid_nr(current), + dev->parent ? dev_name(dev->parent) : "none"); + return ktime_get(); +} + +static void initcall_debug_report(struct device *dev, ktime_t calltime, + void *cb, int error) +{ + ktime_t rettime; + + if (!pm_print_times_enabled) + return; + + rettime = ktime_get(); + dev_info(dev, "%ps returned %d after %Ld usecs\n", cb, error, + (unsigned long long)ktime_us_delta(rettime, calltime)); +} + +/** + * dpm_wait - Wait for a PM operation to complete. + * @dev: Device to wait for. + * @async: If unset, wait only if the device's power.async_suspend flag is set. + */ +static void dpm_wait(struct device *dev, bool async) +{ + if (!dev) + return; + + /* Devices with no PM support don't use the completion. */ + if (dev->power.no_pm) + return; + + if (async || (pm_async_enabled && dev->power.async_suspend)) + wait_for_completion(&dev->power.completion); +} + +static int dpm_wait_fn(struct device *dev, void *async_ptr) +{ + dpm_wait(dev, *((bool *)async_ptr)); + return 0; +} + +static void dpm_wait_for_children(struct device *dev, bool async) +{ + device_for_each_child(dev, &async, dpm_wait_fn); +} + +static void dpm_wait_for_suppliers(struct device *dev, bool async) +{ + struct device_link *link; + int idx; + + idx = device_links_read_lock(); + + /* + * If the supplier goes away right after we've checked the link to it, + * we'll wait for its completion to change the state, but that's fine, + * because the only things that will block as a result are the SRCU + * callbacks freeing the link objects for the links in the list we're + * walking. + */ + dev_for_each_link_to_supplier(link, dev) + if (READ_ONCE(link->status) != DL_STATE_DORMANT && + !device_link_flag_is_sync_state_only(link->flags)) + dpm_wait(link->supplier, async); + + device_links_read_unlock(idx); +} + +static bool dpm_wait_for_superior(struct device *dev, bool async) +{ + struct device *parent; + + /* + * If the device is resumed asynchronously and the parent's callback + * deletes both the device and the parent itself, the parent object may + * be freed while this function is running, so avoid that by reference + * counting the parent once more unless the device has been deleted + * already (in which case return right away). + */ + mutex_lock(&dpm_list_mtx); + + if (!device_pm_initialized(dev)) { + mutex_unlock(&dpm_list_mtx); + return false; + } + + parent = get_device(dev->parent); + + mutex_unlock(&dpm_list_mtx); + + dpm_wait(parent, async); + put_device(parent); + + dpm_wait_for_suppliers(dev, async); + + /* + * If the parent's callback has deleted the device, attempting to resume + * it would be invalid, so avoid doing that then. + */ + return device_pm_initialized(dev); +} + +static void dpm_wait_for_consumers(struct device *dev, bool async) +{ + struct device_link *link; + int idx; + + idx = device_links_read_lock(); + + /* + * The status of a device link can only be changed from "dormant" by a + * probe, but that cannot happen during system suspend/resume. In + * theory it can change to "dormant" at that time, but then it is + * reasonable to wait for the target device anyway (eg. if it goes + * away, it's better to wait for it to go away completely and then + * continue instead of trying to continue in parallel with its + * unregistration). + */ + dev_for_each_link_to_consumer(link, dev) + if (READ_ONCE(link->status) != DL_STATE_DORMANT && + !device_link_flag_is_sync_state_only(link->flags)) + dpm_wait(link->consumer, async); + + device_links_read_unlock(idx); +} + +static void dpm_wait_for_subordinate(struct device *dev, bool async) +{ + dpm_wait_for_children(dev, async); + dpm_wait_for_consumers(dev, async); +} + +/** + * pm_op - Return the PM operation appropriate for given PM event. + * @ops: PM operations to choose from. + * @state: PM transition of the system being carried out. + */ +static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state) +{ + switch (state.event) { +#ifdef CONFIG_SUSPEND + case PM_EVENT_SUSPEND: + return ops->suspend; + case PM_EVENT_RESUME: + return ops->resume; +#endif /* CONFIG_SUSPEND */ +#ifdef CONFIG_HIBERNATE_CALLBACKS + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + return ops->freeze; + case PM_EVENT_POWEROFF: + case PM_EVENT_HIBERNATE: + return ops->poweroff; + case PM_EVENT_THAW: + case PM_EVENT_RECOVER: + return ops->thaw; + case PM_EVENT_RESTORE: + return ops->restore; +#endif /* CONFIG_HIBERNATE_CALLBACKS */ + } + + return NULL; +} + +/** + * pm_late_early_op - Return the PM operation appropriate for given PM event. + * @ops: PM operations to choose from. + * @state: PM transition of the system being carried out. + * + * Runtime PM is disabled for @dev while this function is being executed. + */ +static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops, + pm_message_t state) +{ + switch (state.event) { +#ifdef CONFIG_SUSPEND + case PM_EVENT_SUSPEND: + return ops->suspend_late; + case PM_EVENT_RESUME: + return ops->resume_early; +#endif /* CONFIG_SUSPEND */ +#ifdef CONFIG_HIBERNATE_CALLBACKS + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + return ops->freeze_late; + case PM_EVENT_POWEROFF: + case PM_EVENT_HIBERNATE: + return ops->poweroff_late; + case PM_EVENT_THAW: + case PM_EVENT_RECOVER: + return ops->thaw_early; + case PM_EVENT_RESTORE: + return ops->restore_early; +#endif /* CONFIG_HIBERNATE_CALLBACKS */ + } + + return NULL; +} + +/** + * pm_noirq_op - Return the PM operation appropriate for given PM event. + * @ops: PM operations to choose from. + * @state: PM transition of the system being carried out. + * + * The driver of @dev will not receive interrupts while this function is being + * executed. + */ +static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state) +{ + switch (state.event) { +#ifdef CONFIG_SUSPEND + case PM_EVENT_SUSPEND: + return ops->suspend_noirq; + case PM_EVENT_RESUME: + return ops->resume_noirq; +#endif /* CONFIG_SUSPEND */ +#ifdef CONFIG_HIBERNATE_CALLBACKS + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + return ops->freeze_noirq; + case PM_EVENT_POWEROFF: + case PM_EVENT_HIBERNATE: + return ops->poweroff_noirq; + case PM_EVENT_THAW: + case PM_EVENT_RECOVER: + return ops->thaw_noirq; + case PM_EVENT_RESTORE: + return ops->restore_noirq; +#endif /* CONFIG_HIBERNATE_CALLBACKS */ + } + + return NULL; +} + +static void pm_dev_dbg(struct device *dev, pm_message_t state, const char *info) +{ + dev_dbg(dev, "%s%s%s driver flags: %x\n", info, pm_verb(state.event), + ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ? + ", may wakeup" : "", dev->power.driver_flags); +} + +static void pm_dev_err(struct device *dev, pm_message_t state, const char *info, + int error) +{ + dev_err(dev, "failed to %s%s: error %d\n", pm_verb(state.event), info, + error); +} + +static void dpm_show_time(ktime_t starttime, pm_message_t state, int error, + const char *info) +{ + ktime_t calltime; + u64 usecs64; + int usecs; + + calltime = ktime_get(); + usecs64 = ktime_to_ns(ktime_sub(calltime, starttime)); + do_div(usecs64, NSEC_PER_USEC); + usecs = usecs64; + if (usecs == 0) + usecs = 1; + + pm_pr_dbg("%s%s%s of devices %s after %ld.%03ld msecs\n", + info ?: "", info ? " " : "", pm_verb(state.event), + error ? "aborted" : "complete", + usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC); +} + +static int dpm_run_callback(pm_callback_t cb, struct device *dev, + pm_message_t state, const char *info) +{ + ktime_t calltime; + int error; + + if (!cb) + return 0; + + calltime = initcall_debug_start(dev, cb); + + pm_dev_dbg(dev, state, info); + trace_device_pm_callback_start(dev, info, state.event); + error = cb(dev); + trace_device_pm_callback_end(dev, error); + suspend_report_result(dev, cb, error); + + initcall_debug_report(dev, calltime, cb, error); + + return error; +} + +#ifdef CONFIG_DPM_WATCHDOG +struct dpm_watchdog { + struct device *dev; + struct task_struct *tsk; + struct timer_list timer; + bool fatal; +}; + +#define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \ + struct dpm_watchdog wd + +static bool __read_mostly dpm_watchdog_all_cpu_backtrace; +module_param(dpm_watchdog_all_cpu_backtrace, bool, 0644); +MODULE_PARM_DESC(dpm_watchdog_all_cpu_backtrace, + "Backtrace all CPUs on DPM watchdog timeout"); + +static bool __read_mostly dpm_watchdog_enabled = + IS_ENABLED(CONFIG_DPM_WATCHDOG_ENABLED); +module_param(dpm_watchdog_enabled, bool, 0644); +MODULE_PARM_DESC(dpm_watchdog_enabled, "Enable DPM watchdog"); + +static unsigned int __read_mostly dpm_watchdog_timeout = CONFIG_DPM_WATCHDOG_TIMEOUT; +static unsigned int __read_mostly dpm_watchdog_warning_timeout = + CONFIG_DPM_WATCHDOG_WARNING_TIMEOUT; +static const unsigned int dpm_watchdog_timeout_max = CONFIG_DPM_WATCHDOG_TIMEOUT; + +static int proc_dodpm_watchdog_timeout_secs(const struct ctl_table *table, + int write, void *buffer, + size_t *lenp, loff_t *ppos) +{ + struct ctl_table ctl = *table; + unsigned int val = dpm_watchdog_timeout; + int ret; + + ctl.data = &val; + ret = proc_douintvec_minmax(&ctl, write, buffer, lenp, ppos); + if (ret || !write) + return ret; + + if (val < dpm_watchdog_warning_timeout) + dpm_watchdog_warning_timeout = val; + dpm_watchdog_timeout = val; + + return 0; +} + +static const struct ctl_table dpm_watchdog_sysctls[] = { + { + .procname = "dpm_watchdog_timeout_secs", + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_dodpm_watchdog_timeout_secs, + .extra1 = SYSCTL_ONE, + .extra2 = (void *)&dpm_watchdog_timeout_max, + }, + { + .procname = "dpm_watchdog_warning_timeout_secs", + .data = &dpm_watchdog_warning_timeout, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = SYSCTL_ONE, + .extra2 = (void *)&dpm_watchdog_timeout, + }, +}; + +static int __init dpm_watchdog_sysctl_init(void) +{ + register_sysctl_init("kernel", dpm_watchdog_sysctls); + return 0; +} +subsys_initcall(dpm_watchdog_sysctl_init); + +/** + * dpm_watchdog_handler - Driver suspend / resume watchdog handler. + * @t: The timer that PM watchdog depends on. + * + * Called when a driver has timed out suspending or resuming. + * There's not much we can do here to recover so panic() to + * capture a crash-dump in pstore. + */ +static void dpm_watchdog_handler(struct timer_list *t) +{ + struct dpm_watchdog *wd = timer_container_of(wd, t, timer); + struct timer_list *timer = &wd->timer; + unsigned int time_left; + + if (wd->fatal) { + unsigned int this_cpu = smp_processor_id(); + + dev_emerg(wd->dev, "**** DPM device timeout ****\n"); + show_stack(wd->tsk, NULL, KERN_EMERG); + if (dpm_watchdog_all_cpu_backtrace) + trigger_allbutcpu_cpu_backtrace(this_cpu); + panic("%s %s: unrecoverable failure\n", + dev_driver_string(wd->dev), dev_name(wd->dev)); + } + + time_left = dpm_watchdog_timeout - dpm_watchdog_warning_timeout; + dev_warn(wd->dev, "**** DPM device timeout after %u seconds; %u seconds until panic ****\n", + dpm_watchdog_warning_timeout, time_left); + show_stack(wd->tsk, NULL, KERN_WARNING); + + wd->fatal = true; + mod_timer(timer, jiffies + HZ * time_left); +} + +/** + * dpm_watchdog_set - Enable pm watchdog for given device. + * @wd: Watchdog. Must be allocated on the stack. + * @dev: Device to handle. + */ +static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev) +{ + struct timer_list *timer = &wd->timer; + + if (!dpm_watchdog_enabled) + return; + + wd->dev = dev; + wd->tsk = current; + wd->fatal = dpm_watchdog_timeout == dpm_watchdog_warning_timeout; + + timer_setup_on_stack(timer, dpm_watchdog_handler, 0); + /* use same timeout value for both suspend and resume */ + timer->expires = jiffies + HZ * dpm_watchdog_warning_timeout; + add_timer(timer); +} + +/** + * dpm_watchdog_clear - Disable suspend/resume watchdog. + * @wd: Watchdog to disable. + */ +static void dpm_watchdog_clear(struct dpm_watchdog *wd) +{ + struct timer_list *timer = &wd->timer; + + if (!dpm_watchdog_enabled) + return; + + timer_delete_sync(timer); + timer_destroy_on_stack(timer); +} +#else +#define DECLARE_DPM_WATCHDOG_ON_STACK(wd) +#define dpm_watchdog_set(x, y) +#define dpm_watchdog_clear(x) +#endif + +/*------------------------- Resume routines -------------------------*/ + +/** + * dev_pm_skip_resume - System-wide device resume optimization check. + * @dev: Target device. + * + * Return: + * - %false if the transition under way is RESTORE. + * - Return value of dev_pm_skip_suspend() if the transition under way is THAW. + * - The logical negation of %power.must_resume otherwise (that is, when the + * transition under way is RESUME). + */ +bool dev_pm_skip_resume(struct device *dev) +{ + if (pm_transition.event == PM_EVENT_RESTORE) + return false; + + if (pm_transition.event == PM_EVENT_THAW) + return dev_pm_skip_suspend(dev); + + return !dev->power.must_resume; +} + +static bool is_async(struct device *dev) +{ + return dev->power.async_suspend && pm_async_enabled + && !pm_trace_is_enabled(); +} + +static bool __dpm_async(struct device *dev, async_func_t func) +{ + if (dev->power.work_in_progress) + return true; + + if (!is_async(dev)) + return false; + + dev->power.work_in_progress = true; + + get_device(dev); + + if (async_schedule_dev_nocall(func, dev)) + return true; + + put_device(dev); + + return false; +} + +static bool dpm_async_fn(struct device *dev, async_func_t func) +{ + guard(mutex)(&async_wip_mtx); + + return __dpm_async(dev, func); +} + +static int dpm_async_with_cleanup(struct device *dev, void *fn) +{ + guard(mutex)(&async_wip_mtx); + + if (!__dpm_async(dev, fn)) + dev->power.work_in_progress = false; + + return 0; +} + +static void dpm_async_resume_children(struct device *dev, async_func_t func) +{ + /* + * Prevent racing with dpm_clear_async_state() during initial list + * walks in dpm_noirq_resume_devices(), dpm_resume_early(), and + * dpm_resume(). + */ + guard(mutex)(&dpm_list_mtx); + + /* + * Start processing "async" children of the device unless it's been + * started already for them. + */ + device_for_each_child(dev, func, dpm_async_with_cleanup); +} + +static void dpm_async_resume_subordinate(struct device *dev, async_func_t func) +{ + struct device_link *link; + int idx; + + dpm_async_resume_children(dev, func); + + idx = device_links_read_lock(); + + /* Start processing the device's "async" consumers. */ + dev_for_each_link_to_consumer(link, dev) + if (READ_ONCE(link->status) != DL_STATE_DORMANT) + dpm_async_with_cleanup(link->consumer, func); + + device_links_read_unlock(idx); +} + +static void dpm_clear_async_state(struct device *dev) +{ + reinit_completion(&dev->power.completion); + dev->power.work_in_progress = false; +} + +static bool dpm_root_device(struct device *dev) +{ + lockdep_assert_held(&dpm_list_mtx); + + /* + * Since this function is required to run under dpm_list_mtx, the + * list_empty() below will only return true if the device's list of + * consumers is actually empty before calling it. + */ + return !dev->parent && list_empty(&dev->links.suppliers); +} + +static void async_resume_noirq(void *data, async_cookie_t cookie); + +/** + * device_resume_noirq - Execute a "noirq resume" callback for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * @async: If true, the device is being resumed asynchronously. + * + * The driver of @dev will not receive interrupts while this function is being + * executed. + */ +static void device_resume_noirq(struct device *dev, pm_message_t state, bool async) +{ + pm_callback_t callback = NULL; + const char *info = NULL; + bool skip_resume; + int error = 0; + + TRACE_DEVICE(dev); + TRACE_RESUME(0); + + if (dev->power.syscore || dev->power.direct_complete) + goto Out; + + if (!dev->power.is_noirq_suspended) { + /* + * This means that system suspend has been aborted in the noirq + * phase before invoking the noirq suspend callback for the + * device, so if device_suspend_late() has left it in suspend, + * device_resume_early() should leave it in suspend either in + * case the early resume of it depends on the noirq resume that + * has not run. + */ + if (dev_pm_skip_suspend(dev)) + dev->power.must_resume = false; + + goto Out; + } + + if (!dpm_wait_for_superior(dev, async)) + goto Out; + + skip_resume = dev_pm_skip_resume(dev); + /* + * If the driver callback is skipped below or by the middle layer + * callback and device_resume_early() also skips the driver callback for + * this device later, it needs to appear as "suspended" to PM-runtime, + * so change its status accordingly. + * + * Otherwise, the device is going to be resumed, so set its PM-runtime + * status to "active" unless its power.smart_suspend flag is clear, in + * which case it is not necessary to update its PM-runtime status. + */ + if (skip_resume) + pm_runtime_set_suspended(dev); + else if (dev_pm_smart_suspend(dev)) + pm_runtime_set_active(dev); + + if (dev->pm_domain) { + info = "noirq power domain "; + callback = pm_noirq_op(&dev->pm_domain->ops, state); + } else if (dev->type && dev->type->pm) { + info = "noirq type "; + callback = pm_noirq_op(dev->type->pm, state); + } else if (dev->class && dev->class->pm) { + info = "noirq class "; + callback = pm_noirq_op(dev->class->pm, state); + } else if (dev->bus && dev->bus->pm) { + info = "noirq bus "; + callback = pm_noirq_op(dev->bus->pm, state); + } + if (callback) + goto Run; + + if (skip_resume) + goto Skip; + + if (dev->driver && dev->driver->pm) { + info = "noirq driver "; + callback = pm_noirq_op(dev->driver->pm, state); + } + +Run: + error = dpm_run_callback(callback, dev, state, info); + +Skip: + dev->power.is_noirq_suspended = false; + +Out: + complete_all(&dev->power.completion); + TRACE_RESUME(error); + + if (error) { + WRITE_ONCE(async_error, error); + dpm_save_failed_dev(dev_name(dev)); + pm_dev_err(dev, state, async ? " async noirq" : " noirq", error); + } + + dpm_async_resume_subordinate(dev, async_resume_noirq); +} + +static void async_resume_noirq(void *data, async_cookie_t cookie) +{ + struct device *dev = data; + + device_resume_noirq(dev, pm_transition, true); + put_device(dev); +} + +static void dpm_noirq_resume_devices(pm_message_t state) +{ + struct device *dev; + ktime_t starttime = ktime_get(); + + trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, true); + + async_error = 0; + pm_transition = state; + + mutex_lock(&dpm_list_mtx); + + /* + * Start processing "async" root devices upfront so they don't wait for + * the "sync" devices they don't depend on. + */ + list_for_each_entry(dev, &dpm_noirq_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_root_device(dev)) + dpm_async_with_cleanup(dev, async_resume_noirq); + } + + while (!list_empty(&dpm_noirq_list)) { + dev = to_device(dpm_noirq_list.next); + list_move_tail(&dev->power.entry, &dpm_late_early_list); + + if (!dpm_async_fn(dev, async_resume_noirq)) { + get_device(dev); + + mutex_unlock(&dpm_list_mtx); + + device_resume_noirq(dev, state, false); + + put_device(dev); + + mutex_lock(&dpm_list_mtx); + } + } + mutex_unlock(&dpm_list_mtx); + async_synchronize_full(); + dpm_show_time(starttime, state, 0, "noirq"); + if (READ_ONCE(async_error)) + dpm_save_failed_step(SUSPEND_RESUME_NOIRQ); + + trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false); +} + +/** + * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices. + * @state: PM transition of the system being carried out. + * + * Invoke the "noirq" resume callbacks for all devices in dpm_noirq_list and + * allow device drivers' interrupt handlers to be called. + */ +void dpm_resume_noirq(pm_message_t state) +{ + dpm_noirq_resume_devices(state); + + resume_device_irqs(); + device_wakeup_disarm_wake_irqs(); +} + +static void async_resume_early(void *data, async_cookie_t cookie); + +/** + * device_resume_early - Execute an "early resume" callback for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * @async: If true, the device is being resumed asynchronously. + * + * Runtime PM is disabled for @dev while this function is being executed. + */ +static void device_resume_early(struct device *dev, pm_message_t state, bool async) +{ + pm_callback_t callback = NULL; + const char *info = NULL; + int error = 0; + + TRACE_DEVICE(dev); + TRACE_RESUME(0); + + if (dev->power.direct_complete) + goto Out; + + if (!dev->power.is_late_suspended) + goto Out; + + if (dev->power.syscore) + goto Skip; + + if (!dpm_wait_for_superior(dev, async)) + goto Out; + + if (dev->pm_domain) { + info = "early power domain "; + callback = pm_late_early_op(&dev->pm_domain->ops, state); + } else if (dev->type && dev->type->pm) { + info = "early type "; + callback = pm_late_early_op(dev->type->pm, state); + } else if (dev->class && dev->class->pm) { + info = "early class "; + callback = pm_late_early_op(dev->class->pm, state); + } else if (dev->bus && dev->bus->pm) { + info = "early bus "; + callback = pm_late_early_op(dev->bus->pm, state); + } + if (callback) + goto Run; + + if (dev_pm_skip_resume(dev)) + goto Skip; + + if (dev->driver && dev->driver->pm) { + info = "early driver "; + callback = pm_late_early_op(dev->driver->pm, state); + } + +Run: + error = dpm_run_callback(callback, dev, state, info); + +Skip: + dev->power.is_late_suspended = false; + pm_runtime_enable(dev); + +Out: + TRACE_RESUME(error); + + complete_all(&dev->power.completion); + + if (error) { + WRITE_ONCE(async_error, error); + dpm_save_failed_dev(dev_name(dev)); + pm_dev_err(dev, state, async ? " async early" : " early", error); + } + + dpm_async_resume_subordinate(dev, async_resume_early); +} + +static void async_resume_early(void *data, async_cookie_t cookie) +{ + struct device *dev = data; + + device_resume_early(dev, pm_transition, true); + put_device(dev); +} + +/** + * dpm_resume_early - Execute "early resume" callbacks for all devices. + * @state: PM transition of the system being carried out. + */ +void dpm_resume_early(pm_message_t state) +{ + struct device *dev; + ktime_t starttime = ktime_get(); + + trace_suspend_resume(TPS("dpm_resume_early"), state.event, true); + + async_error = 0; + pm_transition = state; + + mutex_lock(&dpm_list_mtx); + + /* + * Start processing "async" root devices upfront so they don't wait for + * the "sync" devices they don't depend on. + */ + list_for_each_entry(dev, &dpm_late_early_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_root_device(dev)) + dpm_async_with_cleanup(dev, async_resume_early); + } + + while (!list_empty(&dpm_late_early_list)) { + dev = to_device(dpm_late_early_list.next); + list_move_tail(&dev->power.entry, &dpm_suspended_list); + + if (!dpm_async_fn(dev, async_resume_early)) { + get_device(dev); + + mutex_unlock(&dpm_list_mtx); + + device_resume_early(dev, state, false); + + put_device(dev); + + mutex_lock(&dpm_list_mtx); + } + } + mutex_unlock(&dpm_list_mtx); + async_synchronize_full(); + dpm_show_time(starttime, state, 0, "early"); + if (READ_ONCE(async_error)) + dpm_save_failed_step(SUSPEND_RESUME_EARLY); + + trace_suspend_resume(TPS("dpm_resume_early"), state.event, false); +} + +/** + * dpm_resume_start - Execute "noirq" and "early" device callbacks. + * @state: PM transition of the system being carried out. + */ +void dpm_resume_start(pm_message_t state) +{ + dpm_resume_noirq(state); + dpm_resume_early(state); +} +EXPORT_SYMBOL_GPL(dpm_resume_start); + +static void async_resume(void *data, async_cookie_t cookie); + +/** + * device_resume - Execute "resume" callbacks for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * @async: If true, the device is being resumed asynchronously. + */ +static void device_resume(struct device *dev, pm_message_t state, bool async) +{ + pm_callback_t callback = NULL; + const char *info = NULL; + int error = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); + + TRACE_DEVICE(dev); + TRACE_RESUME(0); + + if (dev->power.syscore) + goto Complete; + + if (!dev->power.is_suspended) + goto Complete; + + dev->power.is_suspended = false; + + if (dev->power.direct_complete) { + /* + * Allow new children to be added under the device after this + * point if it has no PM callbacks. + */ + if (dev->power.no_pm_callbacks) + dev->power.is_prepared = false; + + /* Match the pm_runtime_disable() in device_suspend(). */ + pm_runtime_enable(dev); + goto Complete; + } + + if (!dpm_wait_for_superior(dev, async)) + goto Complete; + + dpm_watchdog_set(&wd, dev); + device_lock(dev); + + /* + * This is a fib. But we'll allow new children to be added below + * a resumed device, even if the device hasn't been completed yet. + */ + dev->power.is_prepared = false; + + if (dev->pm_domain) { + info = "power domain "; + callback = pm_op(&dev->pm_domain->ops, state); + goto Driver; + } + + if (dev->type && dev->type->pm) { + info = "type "; + callback = pm_op(dev->type->pm, state); + goto Driver; + } + + if (dev->class && dev->class->pm) { + info = "class "; + callback = pm_op(dev->class->pm, state); + goto Driver; + } + + if (dev->bus) { + if (dev->bus->pm) { + info = "bus "; + callback = pm_op(dev->bus->pm, state); + } else if (dev->bus->resume) { + info = "legacy bus "; + callback = dev->bus->resume; + goto End; + } + } + + Driver: + if (!callback && dev->driver && dev->driver->pm) { + info = "driver "; + callback = pm_op(dev->driver->pm, state); + } + + End: + error = dpm_run_callback(callback, dev, state, info); + + device_unlock(dev); + dpm_watchdog_clear(&wd); + + Complete: + complete_all(&dev->power.completion); + + TRACE_RESUME(error); + + if (error) { + WRITE_ONCE(async_error, error); + dpm_save_failed_dev(dev_name(dev)); + pm_dev_err(dev, state, async ? " async" : "", error); + } + + dpm_async_resume_subordinate(dev, async_resume); +} + +static void async_resume(void *data, async_cookie_t cookie) +{ + struct device *dev = data; + + device_resume(dev, pm_transition, true); + put_device(dev); +} + +/** + * dpm_resume - Execute "resume" callbacks for non-sysdev devices. + * @state: PM transition of the system being carried out. + * + * Execute the appropriate "resume" callback for all devices whose status + * indicates that they are suspended. + */ +void dpm_resume(pm_message_t state) +{ + struct device *dev; + ktime_t starttime = ktime_get(); + + trace_suspend_resume(TPS("dpm_resume"), state.event, true); + + pm_transition = state; + async_error = 0; + + mutex_lock(&dpm_list_mtx); + + /* + * Start processing "async" root devices upfront so they don't wait for + * the "sync" devices they don't depend on. + */ + list_for_each_entry(dev, &dpm_suspended_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_root_device(dev)) + dpm_async_with_cleanup(dev, async_resume); + } + + while (!list_empty(&dpm_suspended_list)) { + dev = to_device(dpm_suspended_list.next); + list_move_tail(&dev->power.entry, &dpm_prepared_list); + + if (!dpm_async_fn(dev, async_resume)) { + get_device(dev); + + mutex_unlock(&dpm_list_mtx); + + device_resume(dev, state, false); + + put_device(dev); + + mutex_lock(&dpm_list_mtx); + } + } + mutex_unlock(&dpm_list_mtx); + async_synchronize_full(); + dpm_show_time(starttime, state, 0, NULL); + if (READ_ONCE(async_error)) + dpm_save_failed_step(SUSPEND_RESUME); + + cpufreq_resume(); + devfreq_resume(); + trace_suspend_resume(TPS("dpm_resume"), state.event, false); +} + +/** + * device_complete - Complete a PM transition for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + */ +static void device_complete(struct device *dev, pm_message_t state) +{ + void (*callback)(struct device *) = NULL; + const char *info = NULL; + + if (dev->power.syscore) + goto out; + + device_lock(dev); + + if (dev->pm_domain) { + info = "completing power domain "; + callback = dev->pm_domain->ops.complete; + } else if (dev->type && dev->type->pm) { + info = "completing type "; + callback = dev->type->pm->complete; + } else if (dev->class && dev->class->pm) { + info = "completing class "; + callback = dev->class->pm->complete; + } else if (dev->bus && dev->bus->pm) { + info = "completing bus "; + callback = dev->bus->pm->complete; + } + + if (!callback && dev->driver && dev->driver->pm) { + info = "completing driver "; + callback = dev->driver->pm->complete; + } + + if (callback) { + pm_dev_dbg(dev, state, info); + callback(dev); + } + + device_unlock(dev); + +out: + /* If enabling runtime PM for the device is blocked, unblock it. */ + pm_runtime_unblock(dev); + pm_runtime_put(dev); +} + +/** + * dpm_complete - Complete a PM transition for all non-sysdev devices. + * @state: PM transition of the system being carried out. + * + * Execute the ->complete() callbacks for all devices whose PM status is not + * DPM_ON (this allows new devices to be registered). + */ +void dpm_complete(pm_message_t state) +{ + struct list_head list; + + trace_suspend_resume(TPS("dpm_complete"), state.event, true); + + INIT_LIST_HEAD(&list); + mutex_lock(&dpm_list_mtx); + while (!list_empty(&dpm_prepared_list)) { + struct device *dev = to_device(dpm_prepared_list.prev); + + get_device(dev); + dev->power.is_prepared = false; + list_move(&dev->power.entry, &list); + + mutex_unlock(&dpm_list_mtx); + + trace_device_pm_callback_start(dev, "", state.event); + device_complete(dev, state); + trace_device_pm_callback_end(dev, 0); + + put_device(dev); + + mutex_lock(&dpm_list_mtx); + } + list_splice(&list, &dpm_list); + mutex_unlock(&dpm_list_mtx); + + /* Start resuming thermal control */ + thermal_pm_complete(); + /* Allow device probing and trigger re-probing of deferred devices */ + device_unblock_probing(); + trace_suspend_resume(TPS("dpm_complete"), state.event, false); +} + +/** + * dpm_resume_end - Execute "resume" callbacks and complete system transition. + * @state: PM transition of the system being carried out. + * + * Execute "resume" callbacks for all devices and complete the PM transition of + * the system. + */ +void dpm_resume_end(pm_message_t state) +{ + dpm_resume(state); + pm_restore_gfp_mask(); + dpm_complete(state); +} +EXPORT_SYMBOL_GPL(dpm_resume_end); + + +/*------------------------- Suspend routines -------------------------*/ + +static bool dpm_leaf_device(struct device *dev) +{ + struct device *child; + + lockdep_assert_held(&dpm_list_mtx); + + child = device_find_any_child(dev); + if (child) { + put_device(child); + + return false; + } + + /* + * Since this function is required to run under dpm_list_mtx, the + * list_empty() below will only return true if the device's list of + * consumers is actually empty before calling it. + */ + return list_empty(&dev->links.consumers); +} + +static bool dpm_async_suspend_parent(struct device *dev, async_func_t func) +{ + guard(mutex)(&dpm_list_mtx); + + /* + * If the device is suspended asynchronously and the parent's callback + * deletes both the device and the parent itself, the parent object may + * be freed while this function is running, so avoid that by checking + * if the device has been deleted already as the parent cannot be + * deleted before it. + */ + if (!device_pm_initialized(dev)) + return false; + + /* Start processing the device's parent if it is "async". */ + if (dev->parent) + dpm_async_with_cleanup(dev->parent, func); + + return true; +} + +static void dpm_async_suspend_superior(struct device *dev, async_func_t func) +{ + struct device_link *link; + int idx; + + if (!dpm_async_suspend_parent(dev, func)) + return; + + idx = device_links_read_lock(); + + /* Start processing the device's "async" suppliers. */ + dev_for_each_link_to_supplier(link, dev) + if (READ_ONCE(link->status) != DL_STATE_DORMANT) + dpm_async_with_cleanup(link->supplier, func); + + device_links_read_unlock(idx); +} + +static void dpm_async_suspend_complete_all(struct list_head *device_list) +{ + struct device *dev; + + guard(mutex)(&async_wip_mtx); + + list_for_each_entry_reverse(dev, device_list, power.entry) { + /* + * In case the device is being waited for and async processing + * has not started for it yet, let the waiters make progress. + */ + if (!dev->power.work_in_progress) + complete_all(&dev->power.completion); + } +} + +/** + * resume_event - Return a "resume" message for given "suspend" sleep state. + * @sleep_state: PM message representing a sleep state. + * + * Return a PM message representing the resume event corresponding to given + * sleep state. + */ +static pm_message_t resume_event(pm_message_t sleep_state) +{ + switch (sleep_state.event) { + case PM_EVENT_SUSPEND: + return PMSG_RESUME; + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + return PMSG_RECOVER; + case PM_EVENT_HIBERNATE: + return PMSG_RESTORE; + } + return PMSG_ON; +} + +static void dpm_superior_set_must_resume(struct device *dev) +{ + struct device_link *link; + int idx; + + if (dev->parent) + dev->parent->power.must_resume = true; + + idx = device_links_read_lock(); + + dev_for_each_link_to_supplier(link, dev) + link->supplier->power.must_resume = true; + + device_links_read_unlock(idx); +} + +static void async_suspend_noirq(void *data, async_cookie_t cookie); + +/** + * device_suspend_noirq - Execute a "noirq suspend" callback for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * @async: If true, the device is being suspended asynchronously. + * + * The driver of @dev will not receive interrupts while this function is being + * executed. + */ +static void device_suspend_noirq(struct device *dev, pm_message_t state, bool async) +{ + pm_callback_t callback = NULL; + const char *info = NULL; + int error = 0; + + TRACE_DEVICE(dev); + TRACE_SUSPEND(0); + + dpm_wait_for_subordinate(dev, async); + + if (READ_ONCE(async_error)) + goto Complete; + + if (dev->power.syscore || dev->power.direct_complete) + goto Complete; + + if (dev->pm_domain) { + info = "noirq power domain "; + callback = pm_noirq_op(&dev->pm_domain->ops, state); + } else if (dev->type && dev->type->pm) { + info = "noirq type "; + callback = pm_noirq_op(dev->type->pm, state); + } else if (dev->class && dev->class->pm) { + info = "noirq class "; + callback = pm_noirq_op(dev->class->pm, state); + } else if (dev->bus && dev->bus->pm) { + info = "noirq bus "; + callback = pm_noirq_op(dev->bus->pm, state); + } + if (callback) + goto Run; + + if (dev_pm_skip_suspend(dev)) + goto Skip; + + if (dev->driver && dev->driver->pm) { + info = "noirq driver "; + callback = pm_noirq_op(dev->driver->pm, state); + } + +Run: + error = dpm_run_callback(callback, dev, state, info); + if (error) { + WRITE_ONCE(async_error, error); + dpm_save_failed_dev(dev_name(dev)); + pm_dev_err(dev, state, async ? " async noirq" : " noirq", error); + goto Complete; + } + +Skip: + dev->power.is_noirq_suspended = true; + + /* + * Devices must be resumed unless they are explicitly allowed to be left + * in suspend, but even in that case skipping the resume of devices that + * were in use right before the system suspend (as indicated by their + * runtime PM usage counters and child counters) would be suboptimal. + */ + if (!(dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME) && + dev->power.may_skip_resume) || !pm_runtime_need_not_resume(dev)) + dev->power.must_resume = true; + + if (dev->power.must_resume) + dpm_superior_set_must_resume(dev); + +Complete: + complete_all(&dev->power.completion); + TRACE_SUSPEND(error); + + if (error || READ_ONCE(async_error)) + return; + + dpm_async_suspend_superior(dev, async_suspend_noirq); +} + +static void async_suspend_noirq(void *data, async_cookie_t cookie) +{ + struct device *dev = data; + + device_suspend_noirq(dev, pm_transition, true); + put_device(dev); +} + +static int dpm_noirq_suspend_devices(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + struct device *dev; + int error; + + trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true); + + pm_transition = state; + async_error = 0; + + mutex_lock(&dpm_list_mtx); + + /* + * Start processing "async" leaf devices upfront so they don't need to + * wait for the "sync" devices they don't depend on. + */ + list_for_each_entry_reverse(dev, &dpm_late_early_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_leaf_device(dev)) + dpm_async_with_cleanup(dev, async_suspend_noirq); + } + + while (!list_empty(&dpm_late_early_list)) { + dev = to_device(dpm_late_early_list.prev); + + list_move(&dev->power.entry, &dpm_noirq_list); + + if (dpm_async_fn(dev, async_suspend_noirq)) + continue; + + get_device(dev); + + mutex_unlock(&dpm_list_mtx); + + device_suspend_noirq(dev, state, false); + + put_device(dev); + + mutex_lock(&dpm_list_mtx); + + if (READ_ONCE(async_error)) { + dpm_async_suspend_complete_all(&dpm_late_early_list); + /* + * Move all devices to the target list to resume them + * properly. + */ + list_splice_init(&dpm_late_early_list, &dpm_noirq_list); + break; + } + } + + mutex_unlock(&dpm_list_mtx); + + async_synchronize_full(); + + error = READ_ONCE(async_error); + if (error) + dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ); + + dpm_show_time(starttime, state, error, "noirq"); + trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, false); + return error; +} + +/** + * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices. + * @state: PM transition of the system being carried out. + * + * Prevent device drivers' interrupt handlers from being called and invoke + * "noirq" suspend callbacks for all non-sysdev devices. + */ +int dpm_suspend_noirq(pm_message_t state) +{ + int ret; + + device_wakeup_arm_wake_irqs(); + suspend_device_irqs(); + + ret = dpm_noirq_suspend_devices(state); + if (ret) + dpm_resume_noirq(resume_event(state)); + + return ret; +} + +static void dpm_propagate_wakeup_to_parent(struct device *dev) +{ + struct device *parent = dev->parent; + + if (!parent) + return; + + spin_lock_irq(&parent->power.lock); + + if (device_wakeup_path(dev) && !parent->power.ignore_children) + parent->power.wakeup_path = true; + + spin_unlock_irq(&parent->power.lock); +} + +static void async_suspend_late(void *data, async_cookie_t cookie); + +/** + * device_suspend_late - Execute a "late suspend" callback for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * @async: If true, the device is being suspended asynchronously. + * + * Runtime PM is disabled for @dev while this function is being executed. + */ +static void device_suspend_late(struct device *dev, pm_message_t state, bool async) +{ + pm_callback_t callback = NULL; + const char *info = NULL; + int error = 0; + + TRACE_DEVICE(dev); + TRACE_SUSPEND(0); + + dpm_wait_for_subordinate(dev, async); + + if (READ_ONCE(async_error)) + goto Complete; + + if (pm_wakeup_pending()) { + WRITE_ONCE(async_error, -EBUSY); + goto Complete; + } + + if (dev->power.direct_complete) + goto Complete; + + /* + * After this point, any runtime PM operations targeting the device + * will fail until the corresponding pm_runtime_enable() call in + * device_resume_early(). + */ + pm_runtime_disable(dev); + + if (dev->power.syscore) + goto Skip; + + if (dev->pm_domain) { + info = "late power domain "; + callback = pm_late_early_op(&dev->pm_domain->ops, state); + } else if (dev->type && dev->type->pm) { + info = "late type "; + callback = pm_late_early_op(dev->type->pm, state); + } else if (dev->class && dev->class->pm) { + info = "late class "; + callback = pm_late_early_op(dev->class->pm, state); + } else if (dev->bus && dev->bus->pm) { + info = "late bus "; + callback = pm_late_early_op(dev->bus->pm, state); + } + if (callback) + goto Run; + + if (dev_pm_skip_suspend(dev)) + goto Skip; + + if (dev->driver && dev->driver->pm) { + info = "late driver "; + callback = pm_late_early_op(dev->driver->pm, state); + } + +Run: + error = dpm_run_callback(callback, dev, state, info); + if (error) { + WRITE_ONCE(async_error, error); + dpm_save_failed_dev(dev_name(dev)); + pm_dev_err(dev, state, async ? " async late" : " late", error); + pm_runtime_enable(dev); + goto Complete; + } + dpm_propagate_wakeup_to_parent(dev); + +Skip: + dev->power.is_late_suspended = true; + +Complete: + TRACE_SUSPEND(error); + complete_all(&dev->power.completion); + + if (error || READ_ONCE(async_error)) + return; + + dpm_async_suspend_superior(dev, async_suspend_late); +} + +static void async_suspend_late(void *data, async_cookie_t cookie) +{ + struct device *dev = data; + + device_suspend_late(dev, pm_transition, true); + put_device(dev); +} + +/** + * dpm_suspend_late - Execute "late suspend" callbacks for all devices. + * @state: PM transition of the system being carried out. + */ +int dpm_suspend_late(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + struct device *dev; + int error; + + trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true); + + pm_transition = state; + async_error = 0; + + wake_up_all_idle_cpus(); + + mutex_lock(&dpm_list_mtx); + + /* + * Start processing "async" leaf devices upfront so they don't need to + * wait for the "sync" devices they don't depend on. + */ + list_for_each_entry_reverse(dev, &dpm_suspended_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_leaf_device(dev)) + dpm_async_with_cleanup(dev, async_suspend_late); + } + + while (!list_empty(&dpm_suspended_list)) { + dev = to_device(dpm_suspended_list.prev); + + list_move(&dev->power.entry, &dpm_late_early_list); + + if (dpm_async_fn(dev, async_suspend_late)) + continue; + + get_device(dev); + + mutex_unlock(&dpm_list_mtx); + + device_suspend_late(dev, state, false); + + put_device(dev); + + mutex_lock(&dpm_list_mtx); + + if (READ_ONCE(async_error)) { + dpm_async_suspend_complete_all(&dpm_suspended_list); + /* + * Move all devices to the target list to resume them + * properly. + */ + list_splice_init(&dpm_suspended_list, &dpm_late_early_list); + break; + } + } + + mutex_unlock(&dpm_list_mtx); + + async_synchronize_full(); + + error = READ_ONCE(async_error); + if (error) { + dpm_save_failed_step(SUSPEND_SUSPEND_LATE); + dpm_resume_early(resume_event(state)); + } + dpm_show_time(starttime, state, error, "late"); + trace_suspend_resume(TPS("dpm_suspend_late"), state.event, false); + return error; +} + +/** + * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks. + * @state: PM transition of the system being carried out. + */ +int dpm_suspend_end(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + int error; + + error = dpm_suspend_late(state); + if (error) + goto out; + + error = dpm_suspend_noirq(state); + if (error) + dpm_resume_early(resume_event(state)); + +out: + dpm_show_time(starttime, state, error, "end"); + return error; +} +EXPORT_SYMBOL_GPL(dpm_suspend_end); + +/** + * legacy_suspend - Execute a legacy (bus or class) suspend callback for device. + * @dev: Device to suspend. + * @state: PM transition of the system being carried out. + * @cb: Suspend callback to execute. + * @info: string description of caller. + */ +static int legacy_suspend(struct device *dev, pm_message_t state, + int (*cb)(struct device *dev, pm_message_t state), + const char *info) +{ + int error; + ktime_t calltime; + + calltime = initcall_debug_start(dev, cb); + + trace_device_pm_callback_start(dev, info, state.event); + error = cb(dev, state); + trace_device_pm_callback_end(dev, error); + suspend_report_result(dev, cb, error); + + initcall_debug_report(dev, calltime, cb, error); + + return error; +} + +static void dpm_clear_superiors_direct_complete(struct device *dev) +{ + struct device_link *link; + int idx; + + if (dev->parent) { + spin_lock_irq(&dev->parent->power.lock); + dev->parent->power.direct_complete = false; + spin_unlock_irq(&dev->parent->power.lock); + } + + idx = device_links_read_lock(); + + dev_for_each_link_to_supplier(link, dev) { + spin_lock_irq(&link->supplier->power.lock); + link->supplier->power.direct_complete = false; + spin_unlock_irq(&link->supplier->power.lock); + } + + device_links_read_unlock(idx); +} + +static void async_suspend(void *data, async_cookie_t cookie); + +/** + * device_suspend - Execute "suspend" callbacks for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * @async: If true, the device is being suspended asynchronously. + */ +static void device_suspend(struct device *dev, pm_message_t state, bool async) +{ + pm_callback_t callback = NULL; + const char *info = NULL; + int error = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); + + TRACE_DEVICE(dev); + TRACE_SUSPEND(0); + + dpm_wait_for_subordinate(dev, async); + + if (READ_ONCE(async_error)) { + dev->power.direct_complete = false; + goto Complete; + } + + /* + * Wait for possible runtime PM transitions of the device in progress + * to complete and if there's a runtime resume request pending for it, + * resume it before proceeding with invoking the system-wide suspend + * callbacks for it. + * + * If the system-wide suspend callbacks below change the configuration + * of the device, they must disable runtime PM for it or otherwise + * ensure that its runtime-resume callbacks will not be confused by that + * change in case they are invoked going forward. + */ + pm_runtime_barrier(dev); + + if (pm_wakeup_pending()) { + dev->power.direct_complete = false; + WRITE_ONCE(async_error, -EBUSY); + goto Complete; + } + + if (dev->power.syscore) + goto Complete; + + /* Avoid direct_complete to let wakeup_path propagate. */ + if (device_may_wakeup(dev) || device_wakeup_path(dev)) + dev->power.direct_complete = false; + + if (dev->power.direct_complete) { + if (pm_runtime_status_suspended(dev)) { + pm_runtime_disable(dev); + if (pm_runtime_status_suspended(dev)) { + pm_dev_dbg(dev, state, "direct-complete "); + dev->power.is_suspended = true; + goto Complete; + } + + pm_runtime_enable(dev); + } + dev->power.direct_complete = false; + } + + dev->power.may_skip_resume = true; + dev->power.must_resume = !dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME); + + dpm_watchdog_set(&wd, dev); + device_lock(dev); + + if (dev->pm_domain) { + info = "power domain "; + callback = pm_op(&dev->pm_domain->ops, state); + goto Run; + } + + if (dev->type && dev->type->pm) { + info = "type "; + callback = pm_op(dev->type->pm, state); + goto Run; + } + + if (dev->class && dev->class->pm) { + info = "class "; + callback = pm_op(dev->class->pm, state); + goto Run; + } + + if (dev->bus) { + if (dev->bus->pm) { + info = "bus "; + callback = pm_op(dev->bus->pm, state); + } else if (dev->bus->suspend) { + pm_dev_dbg(dev, state, "legacy bus "); + error = legacy_suspend(dev, state, dev->bus->suspend, + "legacy bus "); + goto End; + } + } + + Run: + if (!callback && dev->driver && dev->driver->pm) { + info = "driver "; + callback = pm_op(dev->driver->pm, state); + } + + error = dpm_run_callback(callback, dev, state, info); + + End: + if (!error) { + dev->power.is_suspended = true; + if (device_may_wakeup(dev)) + dev->power.wakeup_path = true; + + dpm_propagate_wakeup_to_parent(dev); + dpm_clear_superiors_direct_complete(dev); + } + + device_unlock(dev); + dpm_watchdog_clear(&wd); + + Complete: + if (error) { + WRITE_ONCE(async_error, error); + dpm_save_failed_dev(dev_name(dev)); + pm_dev_err(dev, state, async ? " async" : "", error); + } + + complete_all(&dev->power.completion); + TRACE_SUSPEND(error); + + if (error || READ_ONCE(async_error)) + return; + + dpm_async_suspend_superior(dev, async_suspend); +} + +static void async_suspend(void *data, async_cookie_t cookie) +{ + struct device *dev = data; + + device_suspend(dev, pm_transition, true); + put_device(dev); +} + +/** + * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices. + * @state: PM transition of the system being carried out. + */ +int dpm_suspend(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + struct device *dev; + int error; + + trace_suspend_resume(TPS("dpm_suspend"), state.event, true); + might_sleep(); + + devfreq_suspend(); + cpufreq_suspend(); + + pm_transition = state; + async_error = 0; + + mutex_lock(&dpm_list_mtx); + + /* + * Start processing "async" leaf devices upfront so they don't need to + * wait for the "sync" devices they don't depend on. + */ + list_for_each_entry_reverse(dev, &dpm_prepared_list, power.entry) { + dpm_clear_async_state(dev); + if (dpm_leaf_device(dev)) + dpm_async_with_cleanup(dev, async_suspend); + } + + while (!list_empty(&dpm_prepared_list)) { + dev = to_device(dpm_prepared_list.prev); + + list_move(&dev->power.entry, &dpm_suspended_list); + + if (dpm_async_fn(dev, async_suspend)) + continue; + + get_device(dev); + + mutex_unlock(&dpm_list_mtx); + + device_suspend(dev, state, false); + + put_device(dev); + + mutex_lock(&dpm_list_mtx); + + if (READ_ONCE(async_error)) { + dpm_async_suspend_complete_all(&dpm_prepared_list); + /* + * Move all devices to the target list to resume them + * properly. + */ + list_splice_init(&dpm_prepared_list, &dpm_suspended_list); + break; + } + } + + mutex_unlock(&dpm_list_mtx); + + async_synchronize_full(); + + error = READ_ONCE(async_error); + if (error) + dpm_save_failed_step(SUSPEND_SUSPEND); + + dpm_show_time(starttime, state, error, NULL); + trace_suspend_resume(TPS("dpm_suspend"), state.event, false); + return error; +} + +static bool device_prepare_smart_suspend(struct device *dev) +{ + struct device_link *link; + bool ret = true; + int idx; + + /* + * The "smart suspend" feature is enabled for devices whose drivers ask + * for it and for devices without PM callbacks. + * + * However, if "smart suspend" is not enabled for the device's parent + * or any of its suppliers that take runtime PM into account, it cannot + * be enabled for the device either. + */ + if (!dev->power.no_pm_callbacks && + !dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND)) + return false; + + if (dev->parent && !dev_pm_smart_suspend(dev->parent) && + !dev->parent->power.ignore_children && !pm_runtime_blocked(dev->parent)) + return false; + + idx = device_links_read_lock(); + + dev_for_each_link_to_supplier(link, dev) { + if (!device_link_test(link, DL_FLAG_PM_RUNTIME)) + continue; + + if (!dev_pm_smart_suspend(link->supplier) && + !pm_runtime_blocked(link->supplier)) { + ret = false; + break; + } + } + + device_links_read_unlock(idx); + + return ret; +} + +/** + * device_prepare - Prepare a device for system power transition. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * + * Execute the ->prepare() callback(s) for given device. No new children of the + * device may be registered after this function has returned. + */ +static int device_prepare(struct device *dev, pm_message_t state) +{ + int (*callback)(struct device *) = NULL; + bool smart_suspend; + int ret = 0; + + /* + * If a device's parent goes into runtime suspend at the wrong time, + * it won't be possible to resume the device. To prevent this we + * block runtime suspend here, during the prepare phase, and allow + * it again during the complete phase. + */ + pm_runtime_get_noresume(dev); + /* + * If runtime PM is disabled for the device at this point and it has + * never been enabled so far, it should not be enabled until this system + * suspend-resume cycle is complete, so prepare to trigger a warning on + * subsequent attempts to enable it. + */ + smart_suspend = !pm_runtime_block_if_disabled(dev); + + if (dev->power.syscore) + return 0; + + device_lock(dev); + + dev->power.wakeup_path = false; + dev->power.out_band_wakeup = false; + + if (dev->power.no_pm_callbacks) + goto unlock; + + if (dev->pm_domain) + callback = dev->pm_domain->ops.prepare; + else if (dev->type && dev->type->pm) + callback = dev->type->pm->prepare; + else if (dev->class && dev->class->pm) + callback = dev->class->pm->prepare; + else if (dev->bus && dev->bus->pm) + callback = dev->bus->pm->prepare; + + if (!callback && dev->driver && dev->driver->pm) + callback = dev->driver->pm->prepare; + + if (callback) + ret = callback(dev); + +unlock: + device_unlock(dev); + + if (ret < 0) { + suspend_report_result(dev, callback, ret); + pm_runtime_unblock(dev); + pm_runtime_put(dev); + return ret; + } + /* Do not enable "smart suspend" for devices with disabled runtime PM. */ + if (smart_suspend) + smart_suspend = device_prepare_smart_suspend(dev); + + spin_lock_irq(&dev->power.lock); + + dev->power.smart_suspend = smart_suspend; + /* + * A positive return value from ->prepare() means "this device appears + * to be runtime-suspended and its state is fine, so if it really is + * runtime-suspended, you can leave it in that state provided that you + * will do the same thing with all of its descendants". This only + * applies to suspend transitions, however. + */ + dev->power.direct_complete = state.event == PM_EVENT_SUSPEND && + (ret > 0 || dev->power.no_pm_callbacks) && + !dev_pm_test_driver_flags(dev, DPM_FLAG_NO_DIRECT_COMPLETE); + + spin_unlock_irq(&dev->power.lock); + + return 0; +} + +/** + * dpm_prepare - Prepare all non-sysdev devices for a system PM transition. + * @state: PM transition of the system being carried out. + * + * Execute the ->prepare() callback(s) for all devices. + */ +int dpm_prepare(pm_message_t state) +{ + int error = 0; + + trace_suspend_resume(TPS("dpm_prepare"), state.event, true); + + /* + * Give a chance for the known devices to complete their probes, before + * disable probing of devices. This sync point is important at least + * at boot time + hibernation restore. + */ + wait_for_device_probe(); + /* + * It is unsafe if probing of devices will happen during suspend or + * hibernation and system behavior will be unpredictable in this case. + * So, let's prohibit device's probing here and defer their probes + * instead. The normal behavior will be restored in dpm_complete(). + */ + device_block_probing(); + /* Suspend thermal control. */ + thermal_pm_prepare(); + + mutex_lock(&dpm_list_mtx); + while (!list_empty(&dpm_list) && !error) { + struct device *dev = to_device(dpm_list.next); + + get_device(dev); + + mutex_unlock(&dpm_list_mtx); + + trace_device_pm_callback_start(dev, "", state.event); + error = device_prepare(dev, state); + trace_device_pm_callback_end(dev, error); + + mutex_lock(&dpm_list_mtx); + + if (!error) { + dev->power.is_prepared = true; + if (!list_empty(&dev->power.entry)) + list_move_tail(&dev->power.entry, &dpm_prepared_list); + } else if (error == -EAGAIN) { + error = 0; + } else { + dev_info(dev, "not prepared for power transition: code %d\n", + error); + } + + mutex_unlock(&dpm_list_mtx); + + put_device(dev); + + mutex_lock(&dpm_list_mtx); + } + mutex_unlock(&dpm_list_mtx); + trace_suspend_resume(TPS("dpm_prepare"), state.event, false); + return error; +} + +/** + * dpm_suspend_start - Prepare devices for PM transition and suspend them. + * @state: PM transition of the system being carried out. + * + * Prepare all non-sysdev devices for system PM transition and execute "suspend" + * callbacks for them. + */ +int dpm_suspend_start(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + int error; + + error = dpm_prepare(state); + if (error) + dpm_save_failed_step(SUSPEND_PREPARE); + else { + pm_restrict_gfp_mask(); + error = dpm_suspend(state); + } + + dpm_show_time(starttime, state, error, "start"); + return error; +} +EXPORT_SYMBOL_GPL(dpm_suspend_start); + +void __suspend_report_result(const char *function, struct device *dev, void *fn, int ret) +{ + if (ret) + dev_err(dev, "%s(): %ps returns %d\n", function, fn, ret); +} +EXPORT_SYMBOL_GPL(__suspend_report_result); + +/** + * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete. + * @subordinate: Device that needs to wait for @dev. + * @dev: Device to wait for. + */ +int device_pm_wait_for_dev(struct device *subordinate, struct device *dev) +{ + dpm_wait(dev, subordinate->power.async_suspend); + return async_error; +} +EXPORT_SYMBOL_GPL(device_pm_wait_for_dev); + +/** + * dpm_for_each_dev - device iterator. + * @data: data for the callback. + * @fn: function to be called for each device. + * + * Iterate over devices in dpm_list, and call @fn for each device, + * passing it @data. + */ +void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *)) +{ + struct device *dev; + + if (!fn) + return; + + device_pm_lock(); + list_for_each_entry(dev, &dpm_list, power.entry) + fn(dev, data); + device_pm_unlock(); +} +EXPORT_SYMBOL_GPL(dpm_for_each_dev); + +static bool pm_ops_is_empty(const struct dev_pm_ops *ops) +{ + if (!ops) + return true; + + return !ops->prepare && + !ops->suspend && + !ops->suspend_late && + !ops->suspend_noirq && + !ops->resume_noirq && + !ops->resume_early && + !ops->resume && + !ops->complete; +} + +void device_pm_check_callbacks(struct device *dev) +{ + unsigned long flags; + + spin_lock_irqsave(&dev->power.lock, flags); + dev->power.no_pm_callbacks = + (!dev->bus || (pm_ops_is_empty(dev->bus->pm) && + !dev->bus->suspend && !dev->bus->resume)) && + (!dev->class || pm_ops_is_empty(dev->class->pm)) && + (!dev->type || pm_ops_is_empty(dev->type->pm)) && + (!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) && + (!dev->driver || (pm_ops_is_empty(dev->driver->pm) && + !dev->driver->suspend && !dev->driver->resume)); + spin_unlock_irqrestore(&dev->power.lock, flags); +} + +bool dev_pm_skip_suspend(struct device *dev) +{ + return dev_pm_smart_suspend(dev) && pm_runtime_status_suspended(dev); +} diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h new file mode 100644 index 000000000..8823aceea --- /dev/null +++ b/drivers/base/power/power.h @@ -0,0 +1,177 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <linux/pm_qos.h> + +static inline void device_pm_init_common(struct device *dev) +{ + if (!dev->power.early_init) { + spin_lock_init(&dev->power.lock); + dev->power.qos = NULL; + dev->power.early_init = true; + } +} + +#ifdef CONFIG_PM + +static inline void pm_runtime_early_init(struct device *dev) +{ + dev->power.disable_depth = 1; + device_pm_init_common(dev); +} + +extern void pm_runtime_init(struct device *dev); +extern void pm_runtime_reinit(struct device *dev); +extern void pm_runtime_remove(struct device *dev); +extern u64 pm_runtime_active_time(struct device *dev); + +#define WAKE_IRQ_DEDICATED_ALLOCATED BIT(0) +#define WAKE_IRQ_DEDICATED_MANAGED BIT(1) +#define WAKE_IRQ_DEDICATED_REVERSE BIT(2) +#define WAKE_IRQ_DEDICATED_MASK (WAKE_IRQ_DEDICATED_ALLOCATED | \ + WAKE_IRQ_DEDICATED_MANAGED | \ + WAKE_IRQ_DEDICATED_REVERSE) +#define WAKE_IRQ_DEDICATED_ENABLED BIT(3) + +struct wake_irq { + struct device *dev; + unsigned int status; + int irq; + const char *name; +}; + +extern void dev_pm_arm_wake_irq(struct wake_irq *wirq); +extern void dev_pm_disarm_wake_irq(struct wake_irq *wirq); +extern void dev_pm_enable_wake_irq_check(struct device *dev, + bool can_change_status); +extern void dev_pm_disable_wake_irq_check(struct device *dev, bool cond_disable); +extern void dev_pm_enable_wake_irq_complete(struct device *dev); + +#ifdef CONFIG_PM_SLEEP + +extern void device_wakeup_attach_irq(struct device *dev, struct wake_irq *wakeirq); +extern void device_wakeup_detach_irq(struct device *dev); +extern void device_wakeup_arm_wake_irqs(void); +extern void device_wakeup_disarm_wake_irqs(void); + +#else + +static inline void device_wakeup_attach_irq(struct device *dev, + struct wake_irq *wakeirq) {} + +static inline void device_wakeup_detach_irq(struct device *dev) +{ +} + +#endif /* CONFIG_PM_SLEEP */ + +/* + * sysfs.c + */ + +extern int dpm_sysfs_add(struct device *dev); +extern void dpm_sysfs_remove(struct device *dev); +extern void rpm_sysfs_remove(struct device *dev); +extern int wakeup_sysfs_add(struct device *dev); +extern void wakeup_sysfs_remove(struct device *dev); +extern int pm_qos_sysfs_add_resume_latency(struct device *dev); +extern void pm_qos_sysfs_remove_resume_latency(struct device *dev); +extern int pm_qos_sysfs_add_flags(struct device *dev); +extern void pm_qos_sysfs_remove_flags(struct device *dev); +extern int pm_qos_sysfs_add_latency_tolerance(struct device *dev); +extern void pm_qos_sysfs_remove_latency_tolerance(struct device *dev); +extern int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid); + +#else /* CONFIG_PM */ + +static inline void pm_runtime_early_init(struct device *dev) +{ + device_pm_init_common(dev); +} + +static inline void pm_runtime_init(struct device *dev) {} +static inline void pm_runtime_reinit(struct device *dev) {} +static inline void pm_runtime_remove(struct device *dev) {} + +static inline int dpm_sysfs_add(struct device *dev) { return 0; } +static inline void dpm_sysfs_remove(struct device *dev) {} +static inline int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid, + kgid_t kgid) { return 0; } + +#endif + +#ifdef CONFIG_PM_SLEEP + +/* kernel/power/main.c */ +extern int pm_async_enabled; + +/* drivers/base/power/main.c */ +extern struct list_head dpm_list; /* The active device list */ + +static inline struct device *to_device(struct list_head *entry) +{ + return container_of(entry, struct device, power.entry); +} + +extern void device_pm_sleep_init(struct device *dev); +extern void device_pm_add(struct device *); +extern void device_pm_remove(struct device *); +extern void device_pm_move_before(struct device *, struct device *); +extern void device_pm_move_after(struct device *, struct device *); +extern void device_pm_move_last(struct device *); +extern void device_pm_check_callbacks(struct device *dev); + +static inline bool device_pm_initialized(struct device *dev) +{ + return dev->power.in_dpm_list; +} + +/* drivers/base/power/wakeup_stats.c */ +extern int wakeup_source_sysfs_add(struct device *parent, + struct wakeup_source *ws); +extern void wakeup_source_sysfs_remove(struct wakeup_source *ws); + +extern int pm_wakeup_source_sysfs_add(struct device *parent); + +#else /* !CONFIG_PM_SLEEP */ + +static inline void device_pm_sleep_init(struct device *dev) {} + +static inline void device_pm_add(struct device *dev) {} + +static inline void device_pm_remove(struct device *dev) +{ + pm_runtime_remove(dev); +} + +static inline void device_pm_move_before(struct device *deva, + struct device *devb) {} +static inline void device_pm_move_after(struct device *deva, + struct device *devb) {} +static inline void device_pm_move_last(struct device *dev) {} + +static inline void device_pm_check_callbacks(struct device *dev) {} + +static inline bool device_pm_initialized(struct device *dev) +{ + return device_is_registered(dev); +} + +static inline int pm_wakeup_source_sysfs_add(struct device *parent) +{ + return 0; +} + +#endif /* !CONFIG_PM_SLEEP */ + +static inline void device_pm_init(struct device *dev) +{ + device_pm_init_common(dev); + device_pm_sleep_init(dev); + pm_runtime_init(dev); +} + +#ifdef CONFIG_BPF_SYSCALL +struct bpf_ws_lock { }; +struct bpf_ws_lock *bpf_wakeup_sources_read_lock(void); +void bpf_wakeup_sources_read_unlock(struct bpf_ws_lock *lock); +void *bpf_wakeup_sources_get_head(void); +#endif diff --git a/drivers/base/power/qos-test.c b/drivers/base/power/qos-test.c new file mode 100644 index 000000000..79fc6c441 --- /dev/null +++ b/drivers/base/power/qos-test.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 NXP + */ +#include <kunit/test.h> +#include <linux/pm_qos.h> + +/* Basic test for aggregating two "min" requests */ +static void freq_qos_test_min(struct kunit *test) +{ + struct freq_constraints qos; + struct freq_qos_request req1, req2; + int ret; + + freq_constraints_init(&qos); + memset(&req1, 0, sizeof(req1)); + memset(&req2, 0, sizeof(req2)); + + ret = freq_qos_add_request(&qos, &req1, FREQ_QOS_MIN, 1000); + KUNIT_EXPECT_EQ(test, ret, 1); + ret = freq_qos_add_request(&qos, &req2, FREQ_QOS_MIN, 2000); + KUNIT_EXPECT_EQ(test, ret, 1); + + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MIN), 2000); + + ret = freq_qos_remove_request(&req2); + KUNIT_EXPECT_EQ(test, ret, 1); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MIN), 1000); + + ret = freq_qos_remove_request(&req1); + KUNIT_EXPECT_EQ(test, ret, 1); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MIN), + FREQ_QOS_MIN_DEFAULT_VALUE); +} + +/* Test that requests for MAX_DEFAULT_VALUE have no effect */ +static void freq_qos_test_maxdef(struct kunit *test) +{ + struct freq_constraints qos; + struct freq_qos_request req1, req2; + int ret; + + freq_constraints_init(&qos); + memset(&req1, 0, sizeof(req1)); + memset(&req2, 0, sizeof(req2)); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MAX), + FREQ_QOS_MAX_DEFAULT_VALUE); + + ret = freq_qos_add_request(&qos, &req1, FREQ_QOS_MAX, + FREQ_QOS_MAX_DEFAULT_VALUE); + KUNIT_EXPECT_EQ(test, ret, 0); + ret = freq_qos_add_request(&qos, &req2, FREQ_QOS_MAX, + FREQ_QOS_MAX_DEFAULT_VALUE); + KUNIT_EXPECT_EQ(test, ret, 0); + + /* Add max 1000 */ + ret = freq_qos_update_request(&req1, 1000); + KUNIT_EXPECT_EQ(test, ret, 1); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MAX), 1000); + + /* Add max 2000, no impact */ + ret = freq_qos_update_request(&req2, 2000); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MAX), 1000); + + /* Remove max 1000, new max 2000 */ + ret = freq_qos_remove_request(&req1); + KUNIT_EXPECT_EQ(test, ret, 1); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MAX), 2000); +} + +/* + * Test that a freq_qos_request can be added again after removal + * + * This issue was solved by commit 05ff1ba412fd ("PM: QoS: Invalidate frequency + * QoS requests after removal") + */ +static void freq_qos_test_readd(struct kunit *test) +{ + struct freq_constraints qos; + struct freq_qos_request req; + int ret; + + freq_constraints_init(&qos); + memset(&req, 0, sizeof(req)); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MIN), + FREQ_QOS_MIN_DEFAULT_VALUE); + + /* Add */ + ret = freq_qos_add_request(&qos, &req, FREQ_QOS_MIN, 1000); + KUNIT_EXPECT_EQ(test, ret, 1); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MIN), 1000); + + /* Remove */ + ret = freq_qos_remove_request(&req); + KUNIT_EXPECT_EQ(test, ret, 1); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MIN), + FREQ_QOS_MIN_DEFAULT_VALUE); + + /* Add again */ + ret = freq_qos_add_request(&qos, &req, FREQ_QOS_MIN, 2000); + KUNIT_EXPECT_EQ(test, ret, 1); + KUNIT_EXPECT_EQ(test, freq_qos_read_value(&qos, FREQ_QOS_MIN), 2000); +} + +static struct kunit_case pm_qos_test_cases[] = { + KUNIT_CASE(freq_qos_test_min), + KUNIT_CASE(freq_qos_test_maxdef), + KUNIT_CASE(freq_qos_test_readd), + {}, +}; + +static struct kunit_suite pm_qos_test_module = { + .name = "qos-kunit-test", + .test_cases = pm_qos_test_cases, +}; +kunit_test_suites(&pm_qos_test_module); diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c new file mode 100644 index 000000000..9b69827cb --- /dev/null +++ b/drivers/base/power/qos.c @@ -0,0 +1,983 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Devices PM QoS constraints management + * + * Copyright (C) 2011 Texas Instruments, Inc. + * + * This module exposes the interface to kernel space for specifying + * per-device PM QoS dependencies. It provides infrastructure for registration + * of: + * + * Dependents on a QoS value : register requests + * Watchers of QoS value : get notified when target QoS value changes + * + * This QoS design is best effort based. Dependents register their QoS needs. + * Watchers register to keep track of the current QoS needs of the system. + * Watchers can register a per-device notification callback using the + * dev_pm_qos_*_notifier API. The notification chain data is stored in the + * per-device constraint data struct. + * + * Note about the per-device constraint data struct allocation: + * . The per-device constraints data struct ptr is stored into the device + * dev_pm_info. + * . To minimize the data usage by the per-device constraints, the data struct + * is only allocated at the first call to dev_pm_qos_add_request. + * . The data is later free'd when the device is removed from the system. + * . A global mutex protects the constraints users from the data being + * allocated and free'd. + */ + +#include <linux/pm_qos.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/mutex.h> +#include <linux/export.h> +#include <linux/pm_runtime.h> +#include <linux/err.h> +#include <trace/events/power.h> + +#include "power.h" + +static DEFINE_MUTEX(dev_pm_qos_mtx); +static DEFINE_MUTEX(dev_pm_qos_sysfs_mtx); + +/** + * __dev_pm_qos_flags - Check PM QoS flags for a given device. + * @dev: Device to check the PM QoS flags for. + * @mask: Flags to check against. + * + * This routine must be called with dev->power.lock held. + */ +enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask) +{ + struct dev_pm_qos *qos = dev->power.qos; + struct pm_qos_flags *pqf; + s32 val; + + lockdep_assert_held(&dev->power.lock); + + if (IS_ERR_OR_NULL(qos)) + return PM_QOS_FLAGS_UNDEFINED; + + pqf = &qos->flags; + if (list_empty(&pqf->list)) + return PM_QOS_FLAGS_UNDEFINED; + + val = pqf->effective_flags & mask; + if (val) + return (val == mask) ? PM_QOS_FLAGS_ALL : PM_QOS_FLAGS_SOME; + + return PM_QOS_FLAGS_NONE; +} + +/** + * dev_pm_qos_flags - Check PM QoS flags for a given device (locked). + * @dev: Device to check the PM QoS flags for. + * @mask: Flags to check against. + */ +enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev, s32 mask) +{ + unsigned long irqflags; + enum pm_qos_flags_status ret; + + spin_lock_irqsave(&dev->power.lock, irqflags); + ret = __dev_pm_qos_flags(dev, mask); + spin_unlock_irqrestore(&dev->power.lock, irqflags); + + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_flags); + +/** + * __dev_pm_qos_resume_latency - Get resume latency constraint for a given device. + * @dev: Device to get the PM QoS constraint value for. + * + * This routine must be called with dev->power.lock held. + */ +s32 __dev_pm_qos_resume_latency(struct device *dev) +{ + lockdep_assert_held(&dev->power.lock); + + return dev_pm_qos_raw_resume_latency(dev); +} + +/** + * dev_pm_qos_read_value - Get PM QoS constraint for a given device (locked). + * @dev: Device to get the PM QoS constraint value for. + * @type: QoS request type. + */ +s32 dev_pm_qos_read_value(struct device *dev, enum dev_pm_qos_req_type type) +{ + struct dev_pm_qos *qos = dev->power.qos; + unsigned long flags; + s32 ret; + + spin_lock_irqsave(&dev->power.lock, flags); + + switch (type) { + case DEV_PM_QOS_RESUME_LATENCY: + ret = IS_ERR_OR_NULL(qos) ? PM_QOS_RESUME_LATENCY_NO_CONSTRAINT + : pm_qos_read_value(&qos->resume_latency); + break; + case DEV_PM_QOS_MIN_FREQUENCY: + ret = IS_ERR_OR_NULL(qos) ? PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE + : freq_qos_read_value(&qos->freq, FREQ_QOS_MIN); + break; + case DEV_PM_QOS_MAX_FREQUENCY: + ret = IS_ERR_OR_NULL(qos) ? PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE + : freq_qos_read_value(&qos->freq, FREQ_QOS_MAX); + break; + default: + WARN_ON(1); + ret = 0; + } + + spin_unlock_irqrestore(&dev->power.lock, flags); + + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_read_value); + +/** + * apply_constraint - Add/modify/remove device PM QoS request. + * @req: Constraint request to apply + * @action: Action to perform (add/update/remove). + * @value: Value to assign to the QoS request. + * + * Internal function to update the constraints list using the PM QoS core + * code and if needed call the per-device callbacks. + */ +static int apply_constraint(struct dev_pm_qos_request *req, + enum pm_qos_req_action action, s32 value) +{ + struct dev_pm_qos *qos = req->dev->power.qos; + int ret; + + switch(req->type) { + case DEV_PM_QOS_RESUME_LATENCY: + if (WARN_ON(action != PM_QOS_REMOVE_REQ && value < 0)) + value = 0; + + ret = pm_qos_update_target(&qos->resume_latency, + &req->data.pnode, action, value); + break; + case DEV_PM_QOS_LATENCY_TOLERANCE: + ret = pm_qos_update_target(&qos->latency_tolerance, + &req->data.pnode, action, value); + if (ret) { + value = pm_qos_read_value(&qos->latency_tolerance); + req->dev->power.set_latency_tolerance(req->dev, value); + } + break; + case DEV_PM_QOS_MIN_FREQUENCY: + case DEV_PM_QOS_MAX_FREQUENCY: + ret = freq_qos_apply(&req->data.freq, action, value); + break; + case DEV_PM_QOS_FLAGS: + ret = pm_qos_update_flags(&qos->flags, &req->data.flr, + action, value); + break; + default: + ret = -EINVAL; + } + + return ret; +} + +/* + * dev_pm_qos_constraints_allocate + * @dev: device to allocate data for + * + * Called at the first call to add_request, for constraint data allocation + * Must be called with the dev_pm_qos_mtx mutex held + */ +static int dev_pm_qos_constraints_allocate(struct device *dev) +{ + struct dev_pm_qos *qos; + struct pm_qos_constraints *c; + struct blocking_notifier_head *n; + + qos = kzalloc_obj(*qos); + if (!qos) + return -ENOMEM; + + n = kzalloc_objs(*n, 3); + if (!n) { + kfree(qos); + return -ENOMEM; + } + + c = &qos->resume_latency; + plist_head_init(&c->list); + c->target_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; + c->default_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; + c->no_constraint_value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT; + c->type = PM_QOS_MIN; + c->notifiers = n; + BLOCKING_INIT_NOTIFIER_HEAD(n); + + c = &qos->latency_tolerance; + plist_head_init(&c->list); + c->target_value = PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE; + c->default_value = PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE; + c->no_constraint_value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; + c->type = PM_QOS_MIN; + + freq_constraints_init(&qos->freq); + + INIT_LIST_HEAD(&qos->flags.list); + + spin_lock_irq(&dev->power.lock); + dev->power.qos = qos; + spin_unlock_irq(&dev->power.lock); + + return 0; +} + +static void __dev_pm_qos_hide_latency_limit(struct device *dev); +static void __dev_pm_qos_hide_flags(struct device *dev); + +/** + * dev_pm_qos_constraints_destroy + * @dev: target device + * + * Called from the device PM subsystem on device removal under device_pm_lock(). + */ +void dev_pm_qos_constraints_destroy(struct device *dev) +{ + struct dev_pm_qos *qos; + struct dev_pm_qos_request *req, *tmp; + struct pm_qos_constraints *c; + struct pm_qos_flags *f; + + mutex_lock(&dev_pm_qos_sysfs_mtx); + + /* + * If the device's PM QoS resume latency limit or PM QoS flags have been + * exposed to user space, they have to be hidden at this point. + */ + pm_qos_sysfs_remove_resume_latency(dev); + pm_qos_sysfs_remove_flags(dev); + + mutex_lock(&dev_pm_qos_mtx); + + __dev_pm_qos_hide_latency_limit(dev); + __dev_pm_qos_hide_flags(dev); + + qos = dev->power.qos; + if (!qos) + goto out; + + /* Flush the constraints lists for the device. */ + c = &qos->resume_latency; + plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) { + /* + * Update constraints list and call the notification + * callbacks if needed + */ + apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); + } + + c = &qos->latency_tolerance; + plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) { + apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); + } + + c = &qos->freq.min_freq; + plist_for_each_entry_safe(req, tmp, &c->list, data.freq.pnode) { + apply_constraint(req, PM_QOS_REMOVE_REQ, + PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); + } + + c = &qos->freq.max_freq; + plist_for_each_entry_safe(req, tmp, &c->list, data.freq.pnode) { + apply_constraint(req, PM_QOS_REMOVE_REQ, + PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); + } + + f = &qos->flags; + list_for_each_entry_safe(req, tmp, &f->list, data.flr.node) { + apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); + } + + spin_lock_irq(&dev->power.lock); + dev->power.qos = ERR_PTR(-ENODEV); + spin_unlock_irq(&dev->power.lock); + + kfree(qos->resume_latency.notifiers); + kfree(qos); + + out: + mutex_unlock(&dev_pm_qos_mtx); + + mutex_unlock(&dev_pm_qos_sysfs_mtx); +} + +static bool dev_pm_qos_invalid_req_type(struct device *dev, + enum dev_pm_qos_req_type type) +{ + return type == DEV_PM_QOS_LATENCY_TOLERANCE && + !dev->power.set_latency_tolerance; +} + +static int __dev_pm_qos_add_request(struct device *dev, + struct dev_pm_qos_request *req, + enum dev_pm_qos_req_type type, s32 value) +{ + int ret = 0; + + if (!dev || !req || dev_pm_qos_invalid_req_type(dev, type)) + return -EINVAL; + + if (WARN(dev_pm_qos_request_active(req), + "%s() called for already added request\n", __func__)) + return -EINVAL; + + if (IS_ERR(dev->power.qos)) + ret = -ENODEV; + else if (!dev->power.qos) + ret = dev_pm_qos_constraints_allocate(dev); + + trace_dev_pm_qos_add_request(dev_name(dev), type, value); + if (ret) + return ret; + + req->dev = dev; + req->type = type; + if (req->type == DEV_PM_QOS_MIN_FREQUENCY) + ret = freq_qos_add_request(&dev->power.qos->freq, + &req->data.freq, + FREQ_QOS_MIN, value); + else if (req->type == DEV_PM_QOS_MAX_FREQUENCY) + ret = freq_qos_add_request(&dev->power.qos->freq, + &req->data.freq, + FREQ_QOS_MAX, value); + else + ret = apply_constraint(req, PM_QOS_ADD_REQ, value); + + return ret; +} + +/** + * dev_pm_qos_add_request - inserts new qos request into the list + * @dev: target device for the constraint + * @req: pointer to a preallocated handle + * @type: type of the request + * @value: defines the qos request + * + * This function inserts a new entry in the device constraints list of + * requested qos performance characteristics. It recomputes the aggregate + * QoS expectations of parameters and initializes the dev_pm_qos_request + * handle. Caller needs to save this handle for later use in updates and + * removal. + * + * Returns 1 if the aggregated constraint value has changed, + * 0 if the aggregated constraint value has not changed, + * -EINVAL in case of wrong parameters, -ENOMEM if there's not enough memory + * to allocate for data structures, -ENODEV if the device has just been removed + * from the system. + * + * Callers should ensure that the target device is not RPM_SUSPENDED before + * using this function for requests of type DEV_PM_QOS_FLAGS. + */ +int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, + enum dev_pm_qos_req_type type, s32 value) +{ + int ret; + + mutex_lock(&dev_pm_qos_mtx); + ret = __dev_pm_qos_add_request(dev, req, type, value); + mutex_unlock(&dev_pm_qos_mtx); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_add_request); + +/** + * __dev_pm_qos_update_request - Modify an existing device PM QoS request. + * @req : PM QoS request to modify. + * @new_value: New value to request. + */ +static int __dev_pm_qos_update_request(struct dev_pm_qos_request *req, + s32 new_value) +{ + s32 curr_value; + int ret = 0; + + if (!req) /*guard against callers passing in null */ + return -EINVAL; + + if (WARN(!dev_pm_qos_request_active(req), + "%s() called for unknown object\n", __func__)) + return -EINVAL; + + if (IS_ERR_OR_NULL(req->dev->power.qos)) + return -ENODEV; + + switch(req->type) { + case DEV_PM_QOS_RESUME_LATENCY: + case DEV_PM_QOS_LATENCY_TOLERANCE: + curr_value = req->data.pnode.prio; + break; + case DEV_PM_QOS_MIN_FREQUENCY: + case DEV_PM_QOS_MAX_FREQUENCY: + curr_value = req->data.freq.pnode.prio; + break; + case DEV_PM_QOS_FLAGS: + curr_value = req->data.flr.flags; + break; + default: + return -EINVAL; + } + + trace_dev_pm_qos_update_request(dev_name(req->dev), req->type, + new_value); + if (curr_value != new_value) + ret = apply_constraint(req, PM_QOS_UPDATE_REQ, new_value); + + return ret; +} + +/** + * dev_pm_qos_update_request - modifies an existing qos request + * @req : handle to list element holding a dev_pm_qos request to use + * @new_value: defines the qos request + * + * Updates an existing dev PM qos request along with updating the + * target value. + * + * Attempts are made to make this code callable on hot code paths. + * + * Returns 1 if the aggregated constraint value has changed, + * 0 if the aggregated constraint value has not changed, + * -EINVAL in case of wrong parameters, -ENODEV if the device has been + * removed from the system + * + * Callers should ensure that the target device is not RPM_SUSPENDED before + * using this function for requests of type DEV_PM_QOS_FLAGS. + */ +int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value) +{ + int ret; + + mutex_lock(&dev_pm_qos_mtx); + ret = __dev_pm_qos_update_request(req, new_value); + mutex_unlock(&dev_pm_qos_mtx); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_update_request); + +static int __dev_pm_qos_remove_request(struct dev_pm_qos_request *req) +{ + int ret; + + if (!req) /*guard against callers passing in null */ + return -EINVAL; + + if (WARN(!dev_pm_qos_request_active(req), + "%s() called for unknown object\n", __func__)) + return -EINVAL; + + if (IS_ERR_OR_NULL(req->dev->power.qos)) + return -ENODEV; + + trace_dev_pm_qos_remove_request(dev_name(req->dev), req->type, + PM_QOS_DEFAULT_VALUE); + ret = apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); + return ret; +} + +/** + * dev_pm_qos_remove_request - modifies an existing qos request + * @req: handle to request list element + * + * Will remove pm qos request from the list of constraints and + * recompute the current target value. Call this on slow code paths. + * + * Returns 1 if the aggregated constraint value has changed, + * 0 if the aggregated constraint value has not changed, + * -EINVAL in case of wrong parameters, -ENODEV if the device has been + * removed from the system + * + * Callers should ensure that the target device is not RPM_SUSPENDED before + * using this function for requests of type DEV_PM_QOS_FLAGS. + */ +int dev_pm_qos_remove_request(struct dev_pm_qos_request *req) +{ + int ret; + + mutex_lock(&dev_pm_qos_mtx); + ret = __dev_pm_qos_remove_request(req); + mutex_unlock(&dev_pm_qos_mtx); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_remove_request); + +/** + * dev_pm_qos_add_notifier - sets notification entry for changes to target value + * of per-device PM QoS constraints + * + * @dev: target device for the constraint + * @notifier: notifier block managed by caller. + * @type: request type. + * + * Will register the notifier into a notification chain that gets called + * upon changes to the target value for the device. + * + * If the device's constraints object doesn't exist when this routine is called, + * it will be created (or error code will be returned if that fails). + */ +int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier, + enum dev_pm_qos_req_type type) +{ + int ret = 0; + + mutex_lock(&dev_pm_qos_mtx); + + if (IS_ERR(dev->power.qos)) + ret = -ENODEV; + else if (!dev->power.qos) + ret = dev_pm_qos_constraints_allocate(dev); + + if (ret) + goto unlock; + + switch (type) { + case DEV_PM_QOS_RESUME_LATENCY: + ret = blocking_notifier_chain_register(dev->power.qos->resume_latency.notifiers, + notifier); + break; + case DEV_PM_QOS_MIN_FREQUENCY: + ret = freq_qos_add_notifier(&dev->power.qos->freq, + FREQ_QOS_MIN, notifier); + break; + case DEV_PM_QOS_MAX_FREQUENCY: + ret = freq_qos_add_notifier(&dev->power.qos->freq, + FREQ_QOS_MAX, notifier); + break; + default: + WARN_ON(1); + ret = -EINVAL; + } + +unlock: + mutex_unlock(&dev_pm_qos_mtx); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_add_notifier); + +/** + * dev_pm_qos_remove_notifier - deletes notification for changes to target value + * of per-device PM QoS constraints + * + * @dev: target device for the constraint + * @notifier: notifier block to be removed. + * @type: request type. + * + * Will remove the notifier from the notification chain that gets called + * upon changes to the target value. + */ +int dev_pm_qos_remove_notifier(struct device *dev, + struct notifier_block *notifier, + enum dev_pm_qos_req_type type) +{ + int ret = 0; + + mutex_lock(&dev_pm_qos_mtx); + + /* Silently return if the constraints object is not present. */ + if (IS_ERR_OR_NULL(dev->power.qos)) + goto unlock; + + switch (type) { + case DEV_PM_QOS_RESUME_LATENCY: + ret = blocking_notifier_chain_unregister(dev->power.qos->resume_latency.notifiers, + notifier); + break; + case DEV_PM_QOS_MIN_FREQUENCY: + ret = freq_qos_remove_notifier(&dev->power.qos->freq, + FREQ_QOS_MIN, notifier); + break; + case DEV_PM_QOS_MAX_FREQUENCY: + ret = freq_qos_remove_notifier(&dev->power.qos->freq, + FREQ_QOS_MAX, notifier); + break; + default: + WARN_ON(1); + ret = -EINVAL; + } + +unlock: + mutex_unlock(&dev_pm_qos_mtx); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_remove_notifier); + +/** + * dev_pm_qos_add_ancestor_request - Add PM QoS request for device's ancestor. + * @dev: Device whose ancestor to add the request for. + * @req: Pointer to the preallocated handle. + * @type: Type of the request. + * @value: Constraint latency value. + */ +int dev_pm_qos_add_ancestor_request(struct device *dev, + struct dev_pm_qos_request *req, + enum dev_pm_qos_req_type type, s32 value) +{ + struct device *ancestor = dev->parent; + int ret = -ENODEV; + + switch (type) { + case DEV_PM_QOS_RESUME_LATENCY: + while (ancestor && !ancestor->power.ignore_children) + ancestor = ancestor->parent; + + break; + case DEV_PM_QOS_LATENCY_TOLERANCE: + while (ancestor && !ancestor->power.set_latency_tolerance) + ancestor = ancestor->parent; + + break; + default: + ancestor = NULL; + } + if (ancestor) + ret = dev_pm_qos_add_request(ancestor, req, type, value); + + if (ret < 0) + req->dev = NULL; + + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_add_ancestor_request); + +static void __dev_pm_qos_drop_user_request(struct device *dev, + enum dev_pm_qos_req_type type) +{ + struct dev_pm_qos_request *req = NULL; + + switch(type) { + case DEV_PM_QOS_RESUME_LATENCY: + req = dev->power.qos->resume_latency_req; + dev->power.qos->resume_latency_req = NULL; + break; + case DEV_PM_QOS_LATENCY_TOLERANCE: + req = dev->power.qos->latency_tolerance_req; + dev->power.qos->latency_tolerance_req = NULL; + break; + case DEV_PM_QOS_FLAGS: + req = dev->power.qos->flags_req; + dev->power.qos->flags_req = NULL; + break; + default: + WARN_ON(1); + return; + } + __dev_pm_qos_remove_request(req); + kfree(req); +} + +static void dev_pm_qos_drop_user_request(struct device *dev, + enum dev_pm_qos_req_type type) +{ + mutex_lock(&dev_pm_qos_mtx); + __dev_pm_qos_drop_user_request(dev, type); + mutex_unlock(&dev_pm_qos_mtx); +} + +/** + * dev_pm_qos_expose_latency_limit - Expose PM QoS latency limit to user space. + * @dev: Device whose PM QoS latency limit is to be exposed to user space. + * @value: Initial value of the latency limit. + */ +int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value) +{ + struct dev_pm_qos_request *req; + int ret; + + if (!device_is_registered(dev) || value < 0) + return -EINVAL; + + req = kzalloc_obj(*req); + if (!req) + return -ENOMEM; + + ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_RESUME_LATENCY, value); + if (ret < 0) { + kfree(req); + return ret; + } + + mutex_lock(&dev_pm_qos_sysfs_mtx); + + mutex_lock(&dev_pm_qos_mtx); + + if (IS_ERR_OR_NULL(dev->power.qos)) + ret = -ENODEV; + else if (dev->power.qos->resume_latency_req) + ret = -EEXIST; + + if (ret < 0) { + __dev_pm_qos_remove_request(req); + kfree(req); + mutex_unlock(&dev_pm_qos_mtx); + goto out; + } + dev->power.qos->resume_latency_req = req; + + mutex_unlock(&dev_pm_qos_mtx); + + ret = pm_qos_sysfs_add_resume_latency(dev); + if (ret) + dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_RESUME_LATENCY); + + out: + mutex_unlock(&dev_pm_qos_sysfs_mtx); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_expose_latency_limit); + +static void __dev_pm_qos_hide_latency_limit(struct device *dev) +{ + if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->resume_latency_req) + __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_RESUME_LATENCY); +} + +/** + * dev_pm_qos_hide_latency_limit - Hide PM QoS latency limit from user space. + * @dev: Device whose PM QoS latency limit is to be hidden from user space. + */ +void dev_pm_qos_hide_latency_limit(struct device *dev) +{ + mutex_lock(&dev_pm_qos_sysfs_mtx); + + pm_qos_sysfs_remove_resume_latency(dev); + + mutex_lock(&dev_pm_qos_mtx); + __dev_pm_qos_hide_latency_limit(dev); + mutex_unlock(&dev_pm_qos_mtx); + + mutex_unlock(&dev_pm_qos_sysfs_mtx); +} +EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_limit); + +/** + * dev_pm_qos_expose_flags - Expose PM QoS flags of a device to user space. + * @dev: Device whose PM QoS flags are to be exposed to user space. + * @val: Initial values of the flags. + */ +int dev_pm_qos_expose_flags(struct device *dev, s32 val) +{ + struct dev_pm_qos_request *req; + int ret; + + if (!device_is_registered(dev)) + return -EINVAL; + + req = kzalloc_obj(*req); + if (!req) + return -ENOMEM; + + ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_FLAGS, val); + if (ret < 0) { + kfree(req); + return ret; + } + + pm_runtime_get_sync(dev); + mutex_lock(&dev_pm_qos_sysfs_mtx); + + mutex_lock(&dev_pm_qos_mtx); + + if (IS_ERR_OR_NULL(dev->power.qos)) + ret = -ENODEV; + else if (dev->power.qos->flags_req) + ret = -EEXIST; + + if (ret < 0) { + __dev_pm_qos_remove_request(req); + kfree(req); + mutex_unlock(&dev_pm_qos_mtx); + goto out; + } + dev->power.qos->flags_req = req; + + mutex_unlock(&dev_pm_qos_mtx); + + ret = pm_qos_sysfs_add_flags(dev); + if (ret) + dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS); + + out: + mutex_unlock(&dev_pm_qos_sysfs_mtx); + pm_runtime_put(dev); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_expose_flags); + +static void __dev_pm_qos_hide_flags(struct device *dev) +{ + if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->flags_req) + __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS); +} + +/** + * dev_pm_qos_hide_flags - Hide PM QoS flags of a device from user space. + * @dev: Device whose PM QoS flags are to be hidden from user space. + */ +void dev_pm_qos_hide_flags(struct device *dev) +{ + pm_runtime_get_sync(dev); + mutex_lock(&dev_pm_qos_sysfs_mtx); + + pm_qos_sysfs_remove_flags(dev); + + mutex_lock(&dev_pm_qos_mtx); + __dev_pm_qos_hide_flags(dev); + mutex_unlock(&dev_pm_qos_mtx); + + mutex_unlock(&dev_pm_qos_sysfs_mtx); + pm_runtime_put(dev); +} +EXPORT_SYMBOL_GPL(dev_pm_qos_hide_flags); + +/** + * dev_pm_qos_update_flags - Update PM QoS flags request owned by user space. + * @dev: Device to update the PM QoS flags request for. + * @mask: Flags to set/clear. + * @set: Whether to set or clear the flags (true means set). + */ +int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set) +{ + s32 value; + int ret; + + pm_runtime_get_sync(dev); + mutex_lock(&dev_pm_qos_mtx); + + if (IS_ERR_OR_NULL(dev->power.qos) || !dev->power.qos->flags_req) { + ret = -EINVAL; + goto out; + } + + value = dev_pm_qos_requested_flags(dev); + if (set) + value |= mask; + else + value &= ~mask; + + ret = __dev_pm_qos_update_request(dev->power.qos->flags_req, value); + + out: + mutex_unlock(&dev_pm_qos_mtx); + pm_runtime_put(dev); + return ret; +} + +/** + * dev_pm_qos_get_user_latency_tolerance - Get user space latency tolerance. + * @dev: Device to obtain the user space latency tolerance for. + */ +s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev) +{ + s32 ret; + + mutex_lock(&dev_pm_qos_mtx); + ret = IS_ERR_OR_NULL(dev->power.qos) + || !dev->power.qos->latency_tolerance_req ? + PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT : + dev->power.qos->latency_tolerance_req->data.pnode.prio; + mutex_unlock(&dev_pm_qos_mtx); + return ret; +} + +/** + * dev_pm_qos_update_user_latency_tolerance - Update user space latency tolerance. + * @dev: Device to update the user space latency tolerance for. + * @val: New user space latency tolerance for @dev (negative values disable). + */ +int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val) +{ + int ret; + + mutex_lock(&dev_pm_qos_mtx); + + if (IS_ERR_OR_NULL(dev->power.qos) + || !dev->power.qos->latency_tolerance_req) { + struct dev_pm_qos_request *req; + + if (val < 0) { + if (val == PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT) + ret = 0; + else + ret = -EINVAL; + goto out; + } + req = kzalloc_obj(*req); + if (!req) { + ret = -ENOMEM; + goto out; + } + ret = __dev_pm_qos_add_request(dev, req, DEV_PM_QOS_LATENCY_TOLERANCE, val); + if (ret < 0) { + kfree(req); + goto out; + } + dev->power.qos->latency_tolerance_req = req; + } else { + if (val < 0) { + __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY_TOLERANCE); + ret = 0; + } else { + ret = __dev_pm_qos_update_request(dev->power.qos->latency_tolerance_req, val); + } + } + + out: + mutex_unlock(&dev_pm_qos_mtx); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_update_user_latency_tolerance); + +/** + * dev_pm_qos_expose_latency_tolerance - Expose latency tolerance to userspace + * @dev: Device whose latency tolerance to expose + */ +int dev_pm_qos_expose_latency_tolerance(struct device *dev) +{ + int ret; + + if (!dev->power.set_latency_tolerance) + return -EINVAL; + + mutex_lock(&dev_pm_qos_sysfs_mtx); + ret = pm_qos_sysfs_add_latency_tolerance(dev); + mutex_unlock(&dev_pm_qos_sysfs_mtx); + + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_expose_latency_tolerance); + +/** + * dev_pm_qos_hide_latency_tolerance - Hide latency tolerance from userspace + * @dev: Device whose latency tolerance to hide + */ +void dev_pm_qos_hide_latency_tolerance(struct device *dev) +{ + mutex_lock(&dev_pm_qos_sysfs_mtx); + pm_qos_sysfs_remove_latency_tolerance(dev); + mutex_unlock(&dev_pm_qos_sysfs_mtx); + + /* Remove the request from user space now */ + pm_runtime_get_sync(dev); + dev_pm_qos_update_user_latency_tolerance(dev, + PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT); + pm_runtime_put(dev); +} +EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_tolerance); diff --git a/drivers/base/power/runtime-test.c b/drivers/base/power/runtime-test.c new file mode 100644 index 000000000..1535ad2b0 --- /dev/null +++ b/drivers/base/power/runtime-test.c @@ -0,0 +1,249 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2025 Google, Inc. + */ + +#include <linux/cleanup.h> +#include <linux/pm_runtime.h> +#include <kunit/device.h> +#include <kunit/test.h> + +#define DEVICE_NAME "pm_runtime_test_device" + +static void pm_runtime_depth_test(struct kunit *test) +{ + struct device *dev = kunit_device_register(test, DEVICE_NAME); + + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev); + + pm_runtime_enable(dev); + + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); + KUNIT_EXPECT_EQ(test, 0, pm_runtime_get_sync(dev)); + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + KUNIT_EXPECT_EQ(test, 1, pm_runtime_get_sync(dev)); /* "already active" */ + KUNIT_EXPECT_EQ(test, 0, pm_runtime_put_sync(dev)); + KUNIT_EXPECT_EQ(test, 0, pm_runtime_put_sync(dev)); + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); +} + +/* Test pm_runtime_put() and friends when already suspended. */ +static void pm_runtime_already_suspended_test(struct kunit *test) +{ + struct device *dev = kunit_device_register(test, DEVICE_NAME); + + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev); + + pm_runtime_enable(dev); + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); + + pm_runtime_get_noresume(dev); + KUNIT_EXPECT_EQ(test, 1, pm_runtime_put_sync(dev)); + + KUNIT_EXPECT_EQ(test, 1, pm_runtime_suspend(dev)); + KUNIT_EXPECT_EQ(test, 1, pm_runtime_autosuspend(dev)); + KUNIT_EXPECT_EQ(test, 1, pm_request_autosuspend(dev)); + + pm_runtime_get_noresume(dev); + KUNIT_EXPECT_EQ(test, 1, pm_runtime_put_sync_autosuspend(dev)); + + pm_runtime_get_noresume(dev); + pm_runtime_put_autosuspend(dev); + + /* Grab 2 refcounts */ + pm_runtime_get_noresume(dev); + pm_runtime_get_noresume(dev); + /* The first put() sees usage_count 1 */ + KUNIT_EXPECT_EQ(test, 0, pm_runtime_put_sync_autosuspend(dev)); + /* The second put() sees usage_count 0 but tells us "already suspended". */ + KUNIT_EXPECT_EQ(test, 1, pm_runtime_put_sync_autosuspend(dev)); + + /* Should have remained suspended the whole time. */ + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); +} + +static void pm_runtime_idle_test(struct kunit *test) +{ + struct device *dev = kunit_device_register(test, DEVICE_NAME); + + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev); + + pm_runtime_enable(dev); + + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); + KUNIT_EXPECT_EQ(test, 0, pm_runtime_get_sync(dev)); + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + KUNIT_EXPECT_EQ(test, -EAGAIN, pm_runtime_idle(dev)); + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + pm_runtime_put_noidle(dev); + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + KUNIT_EXPECT_EQ(test, 0, pm_runtime_idle(dev)); + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); + KUNIT_EXPECT_EQ(test, -EAGAIN, pm_runtime_idle(dev)); + KUNIT_EXPECT_EQ(test, -EAGAIN, pm_request_idle(dev)); +} + +static void pm_runtime_disabled_test(struct kunit *test) +{ + struct device *dev = kunit_device_register(test, DEVICE_NAME); + + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev); + + /* Never called pm_runtime_enable() */ + KUNIT_EXPECT_FALSE(test, pm_runtime_enabled(dev)); + + /* "disabled" is treated as "active" */ + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + KUNIT_EXPECT_FALSE(test, pm_runtime_suspended(dev)); + + /* + * Note: these "fail", but they still acquire/release refcounts, so + * keep them balanced. + */ + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_get(dev)); + pm_runtime_put(dev); + + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_get_sync(dev)); + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_put_sync(dev)); + + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_get(dev)); + pm_runtime_put_autosuspend(dev); + + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_resume_and_get(dev)); + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_idle(dev)); + KUNIT_EXPECT_EQ(test, -EACCES, pm_request_idle(dev)); + KUNIT_EXPECT_EQ(test, -EACCES, pm_request_resume(dev)); + KUNIT_EXPECT_EQ(test, -EACCES, pm_request_autosuspend(dev)); + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_suspend(dev)); + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_resume(dev)); + KUNIT_EXPECT_EQ(test, -EACCES, pm_runtime_autosuspend(dev)); + + /* Still disabled */ + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + KUNIT_EXPECT_FALSE(test, pm_runtime_enabled(dev)); +} + +static void pm_runtime_error_test(struct kunit *test) +{ + struct device *dev = kunit_device_register(test, DEVICE_NAME); + + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev); + + pm_runtime_enable(dev); + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); + + /* Fake a .runtime_resume() error */ + dev->power.runtime_error = -EIO; + + /* + * Note: these "fail", but they still acquire/release refcounts, so + * keep them balanced. + */ + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_get(dev)); + pm_runtime_put(dev); + + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_get_sync(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_put_sync(dev)); + + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_get(dev)); + pm_runtime_put_autosuspend(dev); + + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_get(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_put_sync_autosuspend(dev)); + + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_resume_and_get(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_idle(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_request_idle(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_request_resume(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_request_autosuspend(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_suspend(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_resume(dev)); + KUNIT_EXPECT_EQ(test, -EINVAL, pm_runtime_autosuspend(dev)); + + /* Error is still pending */ + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); + KUNIT_EXPECT_EQ(test, -EIO, dev->power.runtime_error); + /* Clear error */ + KUNIT_EXPECT_EQ(test, 0, pm_runtime_set_suspended(dev)); + KUNIT_EXPECT_EQ(test, 0, dev->power.runtime_error); + /* Still suspended */ + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); + + KUNIT_EXPECT_EQ(test, 0, pm_runtime_get(dev)); + pm_runtime_barrier(dev); + pm_runtime_put(dev); + pm_runtime_suspend(dev); /* flush the put(), to suspend */ + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); + + KUNIT_EXPECT_EQ(test, 0, pm_runtime_get_sync(dev)); + KUNIT_EXPECT_EQ(test, 0, pm_runtime_put_sync(dev)); + + KUNIT_EXPECT_EQ(test, 0, pm_runtime_get_sync(dev)); + pm_runtime_put_autosuspend(dev); + + KUNIT_EXPECT_EQ(test, 0, pm_runtime_resume_and_get(dev)); + + /* + * The following should all return -EAGAIN (usage is non-zero) or 1 + * (already resumed). + */ + KUNIT_EXPECT_EQ(test, -EAGAIN, pm_runtime_idle(dev)); + KUNIT_EXPECT_EQ(test, -EAGAIN, pm_request_idle(dev)); + KUNIT_EXPECT_EQ(test, 1, pm_request_resume(dev)); + KUNIT_EXPECT_EQ(test, -EAGAIN, pm_request_autosuspend(dev)); + KUNIT_EXPECT_EQ(test, -EAGAIN, pm_runtime_suspend(dev)); + KUNIT_EXPECT_EQ(test, 1, pm_runtime_resume(dev)); + KUNIT_EXPECT_EQ(test, -EAGAIN, pm_runtime_autosuspend(dev)); + + KUNIT_EXPECT_EQ(test, 0, pm_runtime_put_sync(dev)); + + /* Suspended again */ + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); +} + +/* + * Explore a typical probe() sequence in which a device marks itself powered, + * but doesn't hold any runtime PM reference, so it suspends as soon as it goes + * idle. + */ +static void pm_runtime_probe_active_test(struct kunit *test) +{ + struct device *dev = kunit_device_register(test, DEVICE_NAME); + + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev); + + KUNIT_EXPECT_TRUE(test, pm_runtime_status_suspended(dev)); + + KUNIT_EXPECT_EQ(test, 0, pm_runtime_set_active(dev)); + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + + pm_runtime_enable(dev); + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + + /* Nothing to flush. We stay active. */ + pm_runtime_barrier(dev); + KUNIT_EXPECT_TRUE(test, pm_runtime_active(dev)); + + /* Ask for idle? Now we suspend. */ + KUNIT_EXPECT_EQ(test, 0, pm_runtime_idle(dev)); + KUNIT_EXPECT_TRUE(test, pm_runtime_suspended(dev)); +} + +static struct kunit_case pm_runtime_test_cases[] = { + KUNIT_CASE(pm_runtime_depth_test), + KUNIT_CASE(pm_runtime_already_suspended_test), + KUNIT_CASE(pm_runtime_idle_test), + KUNIT_CASE(pm_runtime_disabled_test), + KUNIT_CASE(pm_runtime_error_test), + KUNIT_CASE(pm_runtime_probe_active_test), + {} +}; + +static struct kunit_suite pm_runtime_test_suite = { + .name = "pm_runtime_test_cases", + .test_cases = pm_runtime_test_cases, +}; + +kunit_test_suite(pm_runtime_test_suite); +MODULE_DESCRIPTION("Runtime power management unit test suite"); +MODULE_LICENSE("GPL"); diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c new file mode 100644 index 000000000..fab38bc98 --- /dev/null +++ b/drivers/base/power/runtime.c @@ -0,0 +1,2118 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/runtime.c - Helper functions for device runtime PM + * + * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * Copyright (C) 2010 Alan Stern <stern@rowland.harvard.edu> + */ +#include <linux/sched/mm.h> +#include <linux/ktime.h> +#include <linux/hrtimer.h> +#include <linux/export.h> +#include <linux/pm_runtime.h> +#include <linux/pm_wakeirq.h> +#include <linux/rculist.h> +#include <trace/events/rpm.h> + +#include "../base.h" +#include "power.h" + +typedef int (*pm_callback_t)(struct device *); + +static inline pm_callback_t get_callback_ptr(const void *start, size_t offset) +{ + return *(pm_callback_t *)(start + offset); +} + +static pm_callback_t __rpm_get_driver_callback(struct device *dev, + size_t cb_offset) +{ + if (dev->driver && dev->driver->pm) + return get_callback_ptr(dev->driver->pm, cb_offset); + + return NULL; +} + +static pm_callback_t __rpm_get_callback(struct device *dev, size_t cb_offset) +{ + const struct dev_pm_ops *ops; + pm_callback_t cb = NULL; + + if (dev->pm_domain) + ops = &dev->pm_domain->ops; + else if (dev->type && dev->type->pm) + ops = dev->type->pm; + else if (dev->class && dev->class->pm) + ops = dev->class->pm; + else if (dev->bus && dev->bus->pm) + ops = dev->bus->pm; + else + ops = NULL; + + if (ops) + cb = get_callback_ptr(ops, cb_offset); + + if (!cb) + cb = __rpm_get_driver_callback(dev, cb_offset); + + return cb; +} + +#define RPM_GET_CALLBACK(dev, callback) \ + __rpm_get_callback(dev, offsetof(struct dev_pm_ops, callback)) + +static int rpm_resume(struct device *dev, int rpmflags); +static int rpm_suspend(struct device *dev, int rpmflags); + +/** + * update_pm_runtime_accounting - Update the time accounting of power states + * @dev: Device to update the accounting for + * + * In order to be able to have time accounting of the various power states + * (as used by programs such as PowerTOP to show the effectiveness of runtime + * PM), we need to track the time spent in each state. + * update_pm_runtime_accounting must be called each time before the + * runtime_status field is updated, to account the time in the old state + * correctly. + */ +static void update_pm_runtime_accounting(struct device *dev) +{ + u64 now, last, delta; + + if (dev->power.disable_depth > 0) + return; + + last = dev->power.accounting_timestamp; + + now = ktime_get_mono_fast_ns(); + dev->power.accounting_timestamp = now; + + /* + * Because ktime_get_mono_fast_ns() is not monotonic during + * timekeeping updates, ensure that 'now' is after the last saved + * timestamp. + */ + if (now < last) + return; + + delta = now - last; + + if (dev->power.runtime_status == RPM_SUSPENDED) + dev->power.suspended_time += delta; + else + dev->power.active_time += delta; +} + +static void __update_runtime_status(struct device *dev, enum rpm_status status) +{ + update_pm_runtime_accounting(dev); + trace_rpm_status(dev, status); + dev->power.runtime_status = status; +} + +static u64 rpm_get_accounted_time(struct device *dev, bool suspended) +{ + u64 time; + unsigned long flags; + + spin_lock_irqsave(&dev->power.lock, flags); + + update_pm_runtime_accounting(dev); + time = suspended ? dev->power.suspended_time : dev->power.active_time; + + spin_unlock_irqrestore(&dev->power.lock, flags); + + return time; +} + +u64 pm_runtime_active_time(struct device *dev) +{ + return rpm_get_accounted_time(dev, false); +} + +u64 pm_runtime_suspended_time(struct device *dev) +{ + return rpm_get_accounted_time(dev, true); +} +EXPORT_SYMBOL_GPL(pm_runtime_suspended_time); + +/** + * pm_runtime_deactivate_timer - Deactivate given device's suspend timer. + * @dev: Device to handle. + */ +static void pm_runtime_deactivate_timer(struct device *dev) +{ + if (dev->power.timer_expires > 0) { + hrtimer_try_to_cancel(&dev->power.suspend_timer); + dev->power.timer_expires = 0; + } +} + +/** + * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests. + * @dev: Device to handle. + */ +static void pm_runtime_cancel_pending(struct device *dev) +{ + pm_runtime_deactivate_timer(dev); + /* + * In case there's a request pending, make sure its work function will + * return without doing anything. + */ + dev->power.request = RPM_REQ_NONE; +} + +/* + * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time. + * @dev: Device to handle. + * + * Compute the autosuspend-delay expiration time based on the device's + * power.last_busy time. If the delay has already expired or is disabled + * (negative) or the power.use_autosuspend flag isn't set, return 0. + * Otherwise return the expiration time in nanoseconds (adjusted to be nonzero). + * + * This function may be called either with or without dev->power.lock held. + * Either way it can be racy, since power.last_busy may be updated at any time. + */ +u64 pm_runtime_autosuspend_expiration(struct device *dev) +{ + int autosuspend_delay; + u64 expires; + + if (!dev->power.use_autosuspend) + return 0; + + autosuspend_delay = READ_ONCE(dev->power.autosuspend_delay); + if (autosuspend_delay < 0) + return 0; + + expires = READ_ONCE(dev->power.last_busy); + expires += (u64)autosuspend_delay * NSEC_PER_MSEC; + if (expires > ktime_get_mono_fast_ns()) + return expires; /* Expires in the future */ + + return 0; +} +EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration); + +static int dev_memalloc_noio(struct device *dev, void *data) +{ + return dev->power.memalloc_noio; +} + +/* + * pm_runtime_set_memalloc_noio - Set a device's memalloc_noio flag. + * @dev: Device to handle. + * @enable: True for setting the flag and False for clearing the flag. + * + * Set the flag for all devices in the path from the device to the + * root device in the device tree if @enable is true, otherwise clear + * the flag for devices in the path whose siblings don't set the flag. + * + * The function should only be called by block device, or network + * device driver for solving the deadlock problem during runtime + * resume/suspend: + * + * If memory allocation with GFP_KERNEL is called inside runtime + * resume/suspend callback of any one of its ancestors(or the + * block device itself), the deadlock may be triggered inside the + * memory allocation since it might not complete until the block + * device becomes active and the involved page I/O finishes. The + * situation is pointed out first by Alan Stern. Network device + * are involved in iSCSI kind of situation. + * + * The lock of dev_hotplug_mutex is held in the function for handling + * hotplug race because pm_runtime_set_memalloc_noio() may be called + * in async probe(). + * + * The function should be called between device_add() and device_del() + * on the affected device(block/network device). + */ +void pm_runtime_set_memalloc_noio(struct device *dev, bool enable) +{ + static DEFINE_MUTEX(dev_hotplug_mutex); + + mutex_lock(&dev_hotplug_mutex); + for (;;) { + bool enabled; + + /* hold power lock since bitfield is not SMP-safe. */ + spin_lock_irq(&dev->power.lock); + enabled = dev->power.memalloc_noio; + dev->power.memalloc_noio = enable; + spin_unlock_irq(&dev->power.lock); + + /* + * not need to enable ancestors any more if the device + * has been enabled. + */ + if (enabled && enable) + break; + + dev = dev->parent; + + /* + * clear flag of the parent device only if all the + * children don't set the flag because ancestor's + * flag was set by any one of the descendants. + */ + if (!dev || (!enable && + device_for_each_child(dev, NULL, dev_memalloc_noio))) + break; + } + mutex_unlock(&dev_hotplug_mutex); +} +EXPORT_SYMBOL_GPL(pm_runtime_set_memalloc_noio); + +/** + * rpm_check_suspend_allowed - Test whether a device may be suspended. + * @dev: Device to test. + */ +static int rpm_check_suspend_allowed(struct device *dev) +{ + int retval = 0; + + if (dev->power.runtime_error) + retval = -EINVAL; + else if (dev->power.disable_depth > 0) + retval = -EACCES; + else if (atomic_read(&dev->power.usage_count)) + retval = -EAGAIN; + else if (!dev->power.ignore_children && atomic_read(&dev->power.child_count)) + retval = -EBUSY; + + /* Pending resume requests take precedence over suspends. */ + else if ((dev->power.deferred_resume && + dev->power.runtime_status == RPM_SUSPENDING) || + (dev->power.request_pending && dev->power.request == RPM_REQ_RESUME)) + retval = -EAGAIN; + else if (__dev_pm_qos_resume_latency(dev) == 0) + retval = -EPERM; + else if (dev->power.runtime_status == RPM_SUSPENDED) + retval = 1; + + return retval; +} + +static int rpm_get_suppliers(struct device *dev) +{ + struct device_link *link; + + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) { + int retval; + + if (!device_link_test(link, DL_FLAG_PM_RUNTIME)) + continue; + + retval = pm_runtime_get_sync(link->supplier); + /* Ignore suppliers with disabled runtime PM. */ + if (retval < 0 && retval != -EACCES) { + pm_runtime_put_noidle(link->supplier); + return retval; + } + refcount_inc(&link->rpm_active); + } + return 0; +} + +/** + * pm_runtime_release_supplier - Drop references to device link's supplier. + * @link: Target device link. + * + * Drop all runtime PM references associated with @link to its supplier device. + */ +void pm_runtime_release_supplier(struct device_link *link) +{ + struct device *supplier = link->supplier; + + /* + * The additional power.usage_count check is a safety net in case + * the rpm_active refcount becomes saturated, in which case + * refcount_dec_not_one() would return true forever, but it is not + * strictly necessary. + */ + while (refcount_dec_not_one(&link->rpm_active) && + atomic_read(&supplier->power.usage_count) > 0) + pm_runtime_put_noidle(supplier); +} + +static void __rpm_put_suppliers(struct device *dev, bool try_to_suspend) +{ + struct device_link *link; + + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) { + pm_runtime_release_supplier(link); + if (try_to_suspend) + pm_request_idle(link->supplier); + } +} + +static void rpm_put_suppliers(struct device *dev) +{ + __rpm_put_suppliers(dev, true); +} + +static void rpm_suspend_suppliers(struct device *dev) +{ + struct device_link *link; + int idx = device_links_read_lock(); + + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) + pm_request_idle(link->supplier); + + device_links_read_unlock(idx); +} + +/** + * __rpm_callback - Run a given runtime PM callback for a given device. + * @cb: Runtime PM callback to run. + * @dev: Device to run the callback for. + */ +static int __rpm_callback(int (*cb)(struct device *), struct device *dev) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int retval = 0, idx; + bool use_links = dev->power.links_count > 0; + + if (dev->power.irq_safe) { + spin_unlock(&dev->power.lock); + } else { + spin_unlock_irq(&dev->power.lock); + + /* + * Resume suppliers if necessary. + * + * The device's runtime PM status cannot change until this + * routine returns, so it is safe to read the status outside of + * the lock. + */ + if (use_links && dev->power.runtime_status == RPM_RESUMING) { + idx = device_links_read_lock(); + + retval = rpm_get_suppliers(dev); + if (retval) { + rpm_put_suppliers(dev); + goto fail; + } + + device_links_read_unlock(idx); + } + } + + if (cb) + retval = cb(dev); + + if (dev->power.irq_safe) { + spin_lock(&dev->power.lock); + } else { + /* + * If the device is suspending and the callback has returned + * success, drop the usage counters of the suppliers that have + * been reference counted on its resume. + * + * Do that if resume fails too. + */ + if (use_links && + ((dev->power.runtime_status == RPM_SUSPENDING && !retval) || + (dev->power.runtime_status == RPM_RESUMING && retval))) { + idx = device_links_read_lock(); + + __rpm_put_suppliers(dev, false); + +fail: + device_links_read_unlock(idx); + } + + spin_lock_irq(&dev->power.lock); + } + + return retval; +} + +/** + * rpm_callback - Run a given runtime PM callback for a given device. + * @cb: Runtime PM callback to run. + * @dev: Device to run the callback for. + */ +static int rpm_callback(int (*cb)(struct device *), struct device *dev) +{ + int retval; + + if (dev->power.memalloc_noio) { + unsigned int noio_flag; + + /* + * Deadlock might be caused if memory allocation with + * GFP_KERNEL happens inside runtime_suspend and + * runtime_resume callbacks of one block device's + * ancestor or the block device itself. Network + * device might be thought as part of iSCSI block + * device, so network device and its ancestor should + * be marked as memalloc_noio too. + */ + noio_flag = memalloc_noio_save(); + retval = __rpm_callback(cb, dev); + memalloc_noio_restore(noio_flag); + } else { + retval = __rpm_callback(cb, dev); + } + + /* + * Since -EACCES means that runtime PM is disabled for the given device, + * it should not be returned by runtime PM callbacks. If it is returned + * nevertheless, assume it to be a transient error and convert it to + * -EAGAIN. + */ + if (retval == -EACCES) + retval = -EAGAIN; + + return retval; +} + +/** + * rpm_idle - Notify device bus type if the device can be suspended. + * @dev: Device to notify the bus type about. + * @rpmflags: Flag bits. + * + * Check if the device's runtime PM status allows it to be suspended. If + * another idle notification has been started earlier, return immediately. If + * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise + * run the ->runtime_idle() callback directly. If the ->runtime_idle callback + * doesn't exist or if it returns 0, call rpm_suspend with the RPM_AUTO flag. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int rpm_idle(struct device *dev, int rpmflags) +{ + int (*callback)(struct device *); + int retval; + + trace_rpm_idle(dev, rpmflags); + retval = rpm_check_suspend_allowed(dev); + if (retval < 0) + ; /* Conditions are wrong. */ + + else if ((rpmflags & RPM_GET_PUT) && retval == 1) + ; /* put() is allowed in RPM_SUSPENDED */ + + /* Idle notifications are allowed only in the RPM_ACTIVE state. */ + else if (dev->power.runtime_status != RPM_ACTIVE) + retval = -EAGAIN; + + /* + * Any pending request other than an idle notification takes + * precedence over us, except that the timer may be running. + */ + else if (dev->power.request_pending && + dev->power.request > RPM_REQ_IDLE) + retval = -EAGAIN; + + /* Act as though RPM_NOWAIT is always set. */ + else if (dev->power.idle_notification) + retval = -EINPROGRESS; + + if (retval) + goto out; + + /* Pending requests need to be canceled. */ + dev->power.request = RPM_REQ_NONE; + + callback = RPM_GET_CALLBACK(dev, runtime_idle); + + /* If no callback assume success. */ + if (!callback || dev->power.no_callbacks) + goto out; + + /* Carry out an asynchronous or a synchronous idle notification. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = RPM_REQ_IDLE; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + } + trace_rpm_return_int(dev, _THIS_IP_, 0); + return 0; + } + + dev->power.idle_notification = true; + + if (dev->power.irq_safe) + spin_unlock(&dev->power.lock); + else + spin_unlock_irq(&dev->power.lock); + + retval = callback(dev); + + if (dev->power.irq_safe) + spin_lock(&dev->power.lock); + else + spin_lock_irq(&dev->power.lock); + + dev->power.idle_notification = false; + wake_up_all(&dev->power.wait_queue); + + out: + trace_rpm_return_int(dev, _THIS_IP_, retval); + return retval ? retval : rpm_suspend(dev, rpmflags | RPM_AUTO); +} + +/** + * rpm_suspend - Carry out runtime suspend of given device. + * @dev: Device to suspend. + * @rpmflags: Flag bits. + * + * Check if the device's runtime PM status allows it to be suspended. + * Cancel a pending idle notification, autosuspend or suspend. If + * another suspend has been started earlier, either return immediately + * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC + * flags. If the RPM_ASYNC flag is set then queue a suspend request; + * otherwise run the ->runtime_suspend() callback directly. When + * ->runtime_suspend succeeded, if a deferred resume was requested while + * the callback was running then carry it out, otherwise send an idle + * notification for its parent (if the suspend succeeded and both + * ignore_children of parent->power and irq_safe of dev->power are not set). + * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO + * flag is set and the next autosuspend-delay expiration time is in the + * future, schedule another autosuspend attempt. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int rpm_suspend(struct device *dev, int rpmflags) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int (*callback)(struct device *); + struct device *parent = NULL; + int retval; + + trace_rpm_suspend(dev, rpmflags); + + repeat: + retval = rpm_check_suspend_allowed(dev); + if (retval < 0) + goto out; /* Conditions are wrong. */ + + /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ + if (dev->power.runtime_status == RPM_RESUMING && !(rpmflags & RPM_ASYNC)) + retval = -EAGAIN; + + if (retval) + goto out; + + /* If the autosuspend_delay time hasn't expired yet, reschedule. */ + if ((rpmflags & RPM_AUTO) && dev->power.runtime_status != RPM_SUSPENDING) { + u64 expires = pm_runtime_autosuspend_expiration(dev); + + if (expires != 0) { + /* Pending requests need to be canceled. */ + dev->power.request = RPM_REQ_NONE; + + /* + * Optimization: If the timer is already running and is + * set to expire at or before the autosuspend delay, + * avoid the overhead of resetting it. Just let it + * expire; pm_suspend_timer_fn() will take care of the + * rest. + */ + if (!(dev->power.timer_expires && + dev->power.timer_expires <= expires)) { + /* + * We add a slack of 25% to gather wakeups + * without sacrificing the granularity. + */ + u64 slack = (u64)READ_ONCE(dev->power.autosuspend_delay) * + (NSEC_PER_MSEC >> 2); + + dev->power.timer_expires = expires; + hrtimer_start_range_ns(&dev->power.suspend_timer, + ns_to_ktime(expires), + slack, + HRTIMER_MODE_ABS); + } + dev->power.timer_autosuspends = 1; + goto out; + } + } + + /* Other scheduled or pending requests need to be canceled. */ + pm_runtime_cancel_pending(dev); + + if (dev->power.runtime_status == RPM_SUSPENDING) { + DEFINE_WAIT(wait); + + if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { + retval = -EINPROGRESS; + goto out; + } + + if (dev->power.irq_safe) { + spin_unlock(&dev->power.lock); + + cpu_relax(); + + spin_lock(&dev->power.lock); + goto repeat; + } + + /* Wait for the other suspend running in parallel with us. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_SUSPENDING) + break; + + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + goto repeat; + } + + if (dev->power.no_callbacks) + goto no_callback; /* Assume success. */ + + /* Carry out an asynchronous or a synchronous suspend. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = (rpmflags & RPM_AUTO) ? + RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + } + goto out; + } + + __update_runtime_status(dev, RPM_SUSPENDING); + + callback = RPM_GET_CALLBACK(dev, runtime_suspend); + + dev_pm_enable_wake_irq_check(dev, true); + retval = rpm_callback(callback, dev); + if (retval) + goto fail; + + dev_pm_enable_wake_irq_complete(dev); + + no_callback: + __update_runtime_status(dev, RPM_SUSPENDED); + pm_runtime_deactivate_timer(dev); + + if (dev->parent) { + parent = dev->parent; + atomic_add_unless(&parent->power.child_count, -1, 0); + } + wake_up_all(&dev->power.wait_queue); + + if (dev->power.deferred_resume) { + dev->power.deferred_resume = false; + rpm_resume(dev, 0); + retval = -EAGAIN; + goto out; + } + + if (dev->power.irq_safe) + goto out; + + /* Maybe the parent is now able to suspend. */ + if (parent && !parent->power.ignore_children) { + spin_unlock(&dev->power.lock); + + spin_lock(&parent->power.lock); + rpm_idle(parent, RPM_ASYNC); + spin_unlock(&parent->power.lock); + + spin_lock(&dev->power.lock); + } + /* Maybe the suppliers are now able to suspend. */ + if (dev->power.links_count > 0) { + spin_unlock_irq(&dev->power.lock); + + rpm_suspend_suppliers(dev); + + spin_lock_irq(&dev->power.lock); + } + + out: + trace_rpm_return_int(dev, _THIS_IP_, retval); + + return retval; + + fail: + dev_pm_disable_wake_irq_check(dev, true); + __update_runtime_status(dev, RPM_ACTIVE); + dev->power.deferred_resume = false; + wake_up_all(&dev->power.wait_queue); + + if (retval != -EAGAIN && retval != -EBUSY) + dev->power.runtime_error = retval; + + /* + * On transient errors, if the callback routine failed an autosuspend, + * and if the last_busy time has been updated so that there is a new + * autosuspend expiration time, automatically reschedule another + * autosuspend. + */ + if (!dev->power.runtime_error && (rpmflags & RPM_AUTO) && + pm_runtime_autosuspend_expiration(dev) != 0) + goto repeat; + + pm_runtime_cancel_pending(dev); + + goto out; +} + +/** + * rpm_resume - Carry out runtime resume of given device. + * @dev: Device to resume. + * @rpmflags: Flag bits. + * + * Check if the device's runtime PM status allows it to be resumed. Cancel + * any scheduled or pending requests. If another resume has been started + * earlier, either return immediately or wait for it to finish, depending on the + * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in + * parallel with this function, either tell the other process to resume after + * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC + * flag is set then queue a resume request; otherwise run the + * ->runtime_resume() callback directly. Queue an idle notification for the + * device if the resume succeeded. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int rpm_resume(struct device *dev, int rpmflags) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int (*callback)(struct device *); + struct device *parent = NULL; + int retval = 0; + + trace_rpm_resume(dev, rpmflags); + + repeat: + if (dev->power.runtime_error) { + retval = -EINVAL; + } else if (dev->power.disable_depth > 0) { + if (dev->power.runtime_status == RPM_ACTIVE && + dev->power.last_status == RPM_ACTIVE) + retval = 1; + else if (rpmflags & RPM_TRANSPARENT) + goto out; + else + retval = -EACCES; + } + if (retval) + goto out; + + /* + * Other scheduled or pending requests need to be canceled. Small + * optimization: If an autosuspend timer is running, leave it running + * rather than cancelling it now only to restart it again in the near + * future. + */ + dev->power.request = RPM_REQ_NONE; + if (!dev->power.timer_autosuspends) + pm_runtime_deactivate_timer(dev); + + if (dev->power.runtime_status == RPM_ACTIVE) { + retval = 1; + goto out; + } + + if (dev->power.runtime_status == RPM_RESUMING || + dev->power.runtime_status == RPM_SUSPENDING) { + DEFINE_WAIT(wait); + + if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { + if (dev->power.runtime_status == RPM_SUSPENDING) { + dev->power.deferred_resume = true; + if (rpmflags & RPM_NOWAIT) + retval = -EINPROGRESS; + } else { + retval = -EINPROGRESS; + } + goto out; + } + + if (dev->power.irq_safe) { + spin_unlock(&dev->power.lock); + + cpu_relax(); + + spin_lock(&dev->power.lock); + goto repeat; + } + + /* Wait for the operation carried out in parallel with us. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_RESUMING && + dev->power.runtime_status != RPM_SUSPENDING) + break; + + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + goto repeat; + } + + /* + * See if we can skip waking up the parent. This is safe only if + * power.no_callbacks is set, because otherwise we don't know whether + * the resume will actually succeed. + */ + if (dev->power.no_callbacks && !parent && dev->parent) { + spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING); + if (dev->parent->power.disable_depth > 0 || + dev->parent->power.ignore_children || + dev->parent->power.runtime_status == RPM_ACTIVE) { + atomic_inc(&dev->parent->power.child_count); + spin_unlock(&dev->parent->power.lock); + retval = 1; + goto no_callback; /* Assume success. */ + } + spin_unlock(&dev->parent->power.lock); + } + + /* Carry out an asynchronous or a synchronous resume. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = RPM_REQ_RESUME; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + } + retval = 0; + goto out; + } + + if (!parent && dev->parent) { + /* + * Increment the parent's usage counter and resume it if + * necessary. Not needed if dev is irq-safe; then the + * parent is permanently resumed. + */ + parent = dev->parent; + if (dev->power.irq_safe) + goto skip_parent; + + spin_unlock(&dev->power.lock); + + pm_runtime_get_noresume(parent); + + spin_lock(&parent->power.lock); + /* + * Resume the parent if it has runtime PM enabled and not been + * set to ignore its children. + */ + if (!parent->power.disable_depth && + !parent->power.ignore_children) { + rpm_resume(parent, 0); + if (parent->power.runtime_status != RPM_ACTIVE) + retval = -EBUSY; + } + spin_unlock(&parent->power.lock); + + spin_lock(&dev->power.lock); + if (retval) + goto out; + + goto repeat; + } + skip_parent: + + if (dev->power.no_callbacks) + goto no_callback; /* Assume success. */ + + __update_runtime_status(dev, RPM_RESUMING); + + callback = RPM_GET_CALLBACK(dev, runtime_resume); + + dev_pm_disable_wake_irq_check(dev, false); + retval = rpm_callback(callback, dev); + if (retval) { + __update_runtime_status(dev, RPM_SUSPENDED); + pm_runtime_cancel_pending(dev); + dev_pm_enable_wake_irq_check(dev, false); + } else { + no_callback: + __update_runtime_status(dev, RPM_ACTIVE); + pm_runtime_mark_last_busy(dev); + if (parent) + atomic_inc(&parent->power.child_count); + } + wake_up_all(&dev->power.wait_queue); + + if (retval >= 0) + rpm_idle(dev, RPM_ASYNC); + + out: + if (parent && !dev->power.irq_safe) { + spin_unlock_irq(&dev->power.lock); + + pm_runtime_put(parent); + + spin_lock_irq(&dev->power.lock); + } + + trace_rpm_return_int(dev, _THIS_IP_, retval); + + return retval; +} + +/** + * pm_runtime_work - Universal runtime PM work function. + * @work: Work structure used for scheduling the execution of this function. + * + * Use @work to get the device object the work is to be done for, determine what + * is to be done and execute the appropriate runtime PM function. + */ +static void pm_runtime_work(struct work_struct *work) +{ + struct device *dev = container_of(work, struct device, power.work); + enum rpm_request req; + + spin_lock_irq(&dev->power.lock); + + if (!dev->power.request_pending) + goto out; + + req = dev->power.request; + dev->power.request = RPM_REQ_NONE; + dev->power.request_pending = false; + + switch (req) { + case RPM_REQ_NONE: + break; + case RPM_REQ_IDLE: + rpm_idle(dev, RPM_NOWAIT); + break; + case RPM_REQ_SUSPEND: + rpm_suspend(dev, RPM_NOWAIT); + break; + case RPM_REQ_AUTOSUSPEND: + rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO); + break; + case RPM_REQ_RESUME: + rpm_resume(dev, RPM_NOWAIT); + break; + } + + out: + spin_unlock_irq(&dev->power.lock); +} + +/** + * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). + * @timer: hrtimer used by pm_schedule_suspend(). + * + * Check if the time is right and queue a suspend request. + */ +static enum hrtimer_restart pm_suspend_timer_fn(struct hrtimer *timer) +{ + struct device *dev = container_of(timer, struct device, power.suspend_timer); + unsigned long flags; + u64 expires; + + spin_lock_irqsave(&dev->power.lock, flags); + + expires = dev->power.timer_expires; + /* + * If 'expires' is after the current time, we've been called + * too early. + */ + if (expires > 0 && expires <= ktime_get_mono_fast_ns()) { + dev->power.timer_expires = 0; + rpm_suspend(dev, dev->power.timer_autosuspends ? + (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC); + } + + spin_unlock_irqrestore(&dev->power.lock, flags); + + return HRTIMER_NORESTART; +} + +/** + * pm_schedule_suspend - Set up a timer to submit a suspend request in future. + * @dev: Device to suspend. + * @delay: Time to wait before submitting a suspend request, in milliseconds. + */ +int pm_schedule_suspend(struct device *dev, unsigned int delay) +{ + unsigned long flags; + u64 expires; + int retval; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (!delay) { + retval = rpm_suspend(dev, RPM_ASYNC); + goto out; + } + + retval = rpm_check_suspend_allowed(dev); + if (retval) + goto out; + + /* Other scheduled or pending requests need to be canceled. */ + pm_runtime_cancel_pending(dev); + + expires = ktime_get_mono_fast_ns() + (u64)delay * NSEC_PER_MSEC; + dev->power.timer_expires = expires; + dev->power.timer_autosuspends = 0; + hrtimer_start(&dev->power.suspend_timer, expires, HRTIMER_MODE_ABS); + + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_schedule_suspend); + +static int rpm_drop_usage_count(struct device *dev) +{ + int ret; + + ret = atomic_sub_return(1, &dev->power.usage_count); + if (ret >= 0) + return ret; + + /* + * Because rpm_resume() does not check the usage counter, it will resume + * the device even if the usage counter is 0 or negative, so it is + * sufficient to increment the usage counter here to reverse the change + * made above. + */ + atomic_inc(&dev->power.usage_count); + dev_warn(dev, "Runtime PM usage count underflow!\n"); + return -EINVAL; +} + +/** + * __pm_runtime_idle - Entry point for runtime idle operations. + * @dev: Device to send idle notification for. + * @rpmflags: Flag bits. + * + * If the RPM_GET_PUT flag is set, decrement the device's usage count and + * return immediately if it is larger than zero (if it becomes negative, log a + * warning, increment it, and return an error). Then carry out an idle + * notification, either synchronous or asynchronous. + * + * This routine may be called in atomic context if the RPM_ASYNC flag is set, + * or if pm_runtime_irq_safe() has been called. + */ +int __pm_runtime_idle(struct device *dev, int rpmflags) +{ + unsigned long flags; + int retval; + + if (rpmflags & RPM_GET_PUT) { + retval = rpm_drop_usage_count(dev); + if (retval < 0) { + return retval; + } else if (retval > 0) { + trace_rpm_usage(dev, rpmflags); + return 0; + } + } + + might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); + + spin_lock_irqsave(&dev->power.lock, flags); + retval = rpm_idle(dev, rpmflags); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(__pm_runtime_idle); + +/** + * __pm_runtime_suspend - Entry point for runtime put/suspend operations. + * @dev: Device to suspend. + * @rpmflags: Flag bits. + * + * If the RPM_GET_PUT flag is set, decrement the device's usage count and + * return immediately if it is larger than zero (if it becomes negative, log a + * warning, increment it, and return an error). Then carry out a suspend, + * either synchronous or asynchronous. + * + * This routine may be called in atomic context if the RPM_ASYNC flag is set, + * or if pm_runtime_irq_safe() has been called. + */ +int __pm_runtime_suspend(struct device *dev, int rpmflags) +{ + unsigned long flags; + int retval; + + if (rpmflags & RPM_GET_PUT) { + retval = rpm_drop_usage_count(dev); + if (retval < 0) { + return retval; + } else if (retval > 0) { + trace_rpm_usage(dev, rpmflags); + return 0; + } + } + + might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); + + spin_lock_irqsave(&dev->power.lock, flags); + retval = rpm_suspend(dev, rpmflags); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(__pm_runtime_suspend); + +/** + * __pm_runtime_resume - Entry point for runtime resume operations. + * @dev: Device to resume. + * @rpmflags: Flag bits. + * + * If the RPM_GET_PUT flag is set, increment the device's usage count. Then + * carry out a resume, either synchronous or asynchronous. + * + * This routine may be called in atomic context if the RPM_ASYNC flag is set, + * or if pm_runtime_irq_safe() has been called. + */ +int __pm_runtime_resume(struct device *dev, int rpmflags) +{ + unsigned long flags; + int retval; + + might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe && + dev->power.runtime_status != RPM_ACTIVE); + + if (rpmflags & RPM_GET_PUT) + atomic_inc(&dev->power.usage_count); + + spin_lock_irqsave(&dev->power.lock, flags); + retval = rpm_resume(dev, rpmflags); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(__pm_runtime_resume); + +/** + * pm_runtime_get_conditional - Conditionally bump up device usage counter. + * @dev: Device to handle. + * @ign_usage_count: Whether or not to look at the current usage counter value. + * + * Return -EINVAL if runtime PM is disabled for @dev. + * + * Otherwise, if its runtime PM status is %RPM_ACTIVE and (1) @ign_usage_count + * is set, or (2) @dev is not ignoring children and its active child count is + * nonzero, or (3) the runtime PM usage counter of @dev is not zero, increment + * the usage counter of @dev and return 1. + * + * Otherwise, return 0 without changing the usage counter. + * + * If @ign_usage_count is %true, this function can be used to prevent suspending + * the device when its runtime PM status is %RPM_ACTIVE. + * + * If @ign_usage_count is %false, this function can be used to prevent + * suspending the device when both its runtime PM status is %RPM_ACTIVE and its + * runtime PM usage counter is not zero. + * + * The caller is responsible for decrementing the runtime PM usage counter of + * @dev after this function has returned a positive value for it. + */ +static int pm_runtime_get_conditional(struct device *dev, bool ign_usage_count) +{ + unsigned long flags; + int retval; + + spin_lock_irqsave(&dev->power.lock, flags); + if (dev->power.disable_depth > 0) { + retval = -EINVAL; + } else if (dev->power.runtime_status != RPM_ACTIVE) { + retval = 0; + } else if (ign_usage_count || (!dev->power.ignore_children && + atomic_read(&dev->power.child_count) > 0)) { + retval = 1; + atomic_inc(&dev->power.usage_count); + } else { + retval = atomic_inc_not_zero(&dev->power.usage_count); + } + trace_rpm_usage(dev, 0); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} + +/** + * pm_runtime_get_if_active - Bump up runtime PM usage counter if the device is + * in active state + * @dev: Target device. + * + * Increment the runtime PM usage counter of @dev if its runtime PM status is + * %RPM_ACTIVE, in which case it returns 1. If the device is in a different + * state, 0 is returned. -EINVAL is returned if runtime PM is disabled for the + * device, in which case also the usage_count will remain unmodified. + */ +int pm_runtime_get_if_active(struct device *dev) +{ + return pm_runtime_get_conditional(dev, true); +} +EXPORT_SYMBOL_GPL(pm_runtime_get_if_active); + +/** + * pm_runtime_get_if_in_use - Conditionally bump up runtime PM usage counter. + * @dev: Target device. + * + * Increment the runtime PM usage counter of @dev if its runtime PM status is + * %RPM_ACTIVE and its runtime PM usage counter is greater than 0 or it is not + * ignoring children and its active child count is nonzero. 1 is returned in + * this case. + * + * If @dev is in a different state or it is not in use (that is, its usage + * counter is 0, or it is ignoring children, or its active child count is 0), + * 0 is returned. + * + * -EINVAL is returned if runtime PM is disabled for the device, in which case + * also the usage counter of @dev is not updated. + */ +int pm_runtime_get_if_in_use(struct device *dev) +{ + return pm_runtime_get_conditional(dev, false); +} +EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use); + +/** + * __pm_runtime_set_status - Set runtime PM status of a device. + * @dev: Device to handle. + * @status: New runtime PM status of the device. + * + * If runtime PM of the device is disabled or its power.runtime_error field is + * different from zero, the status may be changed either to RPM_ACTIVE, or to + * RPM_SUSPENDED, as long as that reflects the actual state of the device. + * However, if the device has a parent and the parent is not active, and the + * parent's power.ignore_children flag is unset, the device's status cannot be + * set to RPM_ACTIVE, so -EBUSY is returned in that case. + * + * If successful, __pm_runtime_set_status() clears the power.runtime_error field + * and the device parent's counter of unsuspended children is modified to + * reflect the new status. If the new status is RPM_SUSPENDED, an idle + * notification request for the parent is submitted. + * + * If @dev has any suppliers (as reflected by device links to them), and @status + * is RPM_ACTIVE, they will be activated upfront and if the activation of one + * of them fails, the status of @dev will be changed to RPM_SUSPENDED (instead + * of the @status value) and the suppliers will be deacticated on exit. The + * error returned by the failing supplier activation will be returned in that + * case. + */ +int __pm_runtime_set_status(struct device *dev, unsigned int status) +{ + struct device *parent = dev->parent; + bool notify_parent = false; + unsigned long flags; + int error = 0; + + if (status != RPM_ACTIVE && status != RPM_SUSPENDED) + return -EINVAL; + + spin_lock_irqsave(&dev->power.lock, flags); + + /* + * Prevent PM-runtime from being enabled for the device or return an + * error if it is enabled already and working. + */ + if (dev->power.runtime_error || dev->power.disable_depth) + dev->power.disable_depth++; + else + error = -EAGAIN; + + spin_unlock_irqrestore(&dev->power.lock, flags); + + if (error) + return error; + + /* + * If the new status is RPM_ACTIVE, the suppliers can be activated + * upfront regardless of the current status, because next time + * rpm_put_suppliers() runs, the rpm_active refcounts of the links + * involved will be dropped down to one anyway. + */ + if (status == RPM_ACTIVE) { + int idx = device_links_read_lock(); + + error = rpm_get_suppliers(dev); + if (error) + status = RPM_SUSPENDED; + + device_links_read_unlock(idx); + } + + spin_lock_irqsave(&dev->power.lock, flags); + + if (dev->power.runtime_status == status || !parent) + goto out_set; + + if (status == RPM_SUSPENDED) { + atomic_add_unless(&parent->power.child_count, -1, 0); + notify_parent = !parent->power.ignore_children; + } else { + spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING); + + /* + * It is invalid to put an active child under a parent that is + * not active, has runtime PM enabled and the + * 'power.ignore_children' flag unset. + */ + if (!parent->power.disable_depth && + !parent->power.ignore_children && + parent->power.runtime_status != RPM_ACTIVE) { + dev_err(dev, "runtime PM trying to activate child device %s but parent (%s) is not active\n", + dev_name(dev), + dev_name(parent)); + error = -EBUSY; + } else if (dev->power.runtime_status == RPM_SUSPENDED) { + atomic_inc(&parent->power.child_count); + } + + spin_unlock(&parent->power.lock); + + if (error) { + status = RPM_SUSPENDED; + goto out; + } + } + + out_set: + __update_runtime_status(dev, status); + if (!error) + dev->power.runtime_error = 0; + + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + + if (notify_parent) + pm_request_idle(parent); + + if (status == RPM_SUSPENDED) { + int idx = device_links_read_lock(); + + rpm_put_suppliers(dev); + + device_links_read_unlock(idx); + } + + pm_runtime_enable(dev); + + return error; +} +EXPORT_SYMBOL_GPL(__pm_runtime_set_status); + +/** + * __pm_runtime_barrier - Cancel pending requests and wait for completions. + * @dev: Device to handle. + * + * Flush all pending requests for the device from pm_wq and wait for all + * runtime PM operations involving the device in progress to complete. + * + * Should be called under dev->power.lock with interrupts disabled. + */ +static void __pm_runtime_barrier(struct device *dev) +{ + pm_runtime_deactivate_timer(dev); + + if (dev->power.request_pending) { + dev->power.request = RPM_REQ_NONE; + spin_unlock_irq(&dev->power.lock); + + cancel_work_sync(&dev->power.work); + + spin_lock_irq(&dev->power.lock); + dev->power.request_pending = false; + } + + if (dev->power.runtime_status == RPM_SUSPENDING || + dev->power.runtime_status == RPM_RESUMING || + dev->power.idle_notification) { + DEFINE_WAIT(wait); + + /* Suspend, wake-up or idle notification in progress. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_SUSPENDING + && dev->power.runtime_status != RPM_RESUMING + && !dev->power.idle_notification) + break; + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + } +} + +/** + * pm_runtime_barrier - Flush pending requests and wait for completions. + * @dev: Device to handle. + * + * Prevent the device from being suspended by incrementing its usage counter and + * if there's a pending resume request for the device, wake the device up. + * Next, make sure that all pending requests for the device have been flushed + * from pm_wq and wait for all runtime PM operations involving the device in + * progress to complete. + */ +void pm_runtime_barrier(struct device *dev) +{ + pm_runtime_get_noresume(dev); + spin_lock_irq(&dev->power.lock); + + if (dev->power.request_pending + && dev->power.request == RPM_REQ_RESUME) + rpm_resume(dev, 0); + + __pm_runtime_barrier(dev); + + spin_unlock_irq(&dev->power.lock); + pm_runtime_put_noidle(dev); +} +EXPORT_SYMBOL_GPL(pm_runtime_barrier); + +bool pm_runtime_block_if_disabled(struct device *dev) +{ + bool ret; + + spin_lock_irq(&dev->power.lock); + + ret = !pm_runtime_enabled(dev); + if (ret && dev->power.last_status == RPM_INVALID) + dev->power.last_status = RPM_BLOCKED; + + spin_unlock_irq(&dev->power.lock); + + return ret; +} + +void pm_runtime_unblock(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + + if (dev->power.last_status == RPM_BLOCKED) + dev->power.last_status = RPM_INVALID; + + spin_unlock_irq(&dev->power.lock); +} + +void __pm_runtime_disable(struct device *dev, bool check_resume) +{ + spin_lock_irq(&dev->power.lock); + + if (dev->power.disable_depth > 0) { + dev->power.disable_depth++; + goto out; + } + + /* + * Wake up the device if there's a resume request pending, because that + * means there probably is some I/O to process and disabling runtime PM + * shouldn't prevent the device from processing the I/O. + */ + if (check_resume && dev->power.request_pending && + dev->power.request == RPM_REQ_RESUME) { + /* + * Prevent suspends and idle notifications from being carried + * out after we have woken up the device. + */ + pm_runtime_get_noresume(dev); + + rpm_resume(dev, 0); + + pm_runtime_put_noidle(dev); + } + + /* Update time accounting before disabling PM-runtime. */ + update_pm_runtime_accounting(dev); + + if (!dev->power.disable_depth++) { + __pm_runtime_barrier(dev); + dev->power.last_status = dev->power.runtime_status; + } + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(__pm_runtime_disable); + +/** + * pm_runtime_enable - Enable runtime PM of a device. + * @dev: Device to handle. + */ +void pm_runtime_enable(struct device *dev) +{ + unsigned long flags; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (!dev->power.disable_depth) { + dev_warn(dev, "Unbalanced %s!\n", __func__); + goto out; + } + + if (--dev->power.disable_depth > 0) + goto out; + + if (dev->power.last_status == RPM_BLOCKED) { + dev_warn(dev, "Attempt to enable runtime PM when it is blocked\n"); + dump_stack(); + } + dev->power.last_status = RPM_INVALID; + dev->power.accounting_timestamp = ktime_get_mono_fast_ns(); + + if (dev->power.runtime_status == RPM_SUSPENDED && + !dev->power.ignore_children && + atomic_read(&dev->power.child_count) > 0) + dev_warn(dev, "Enabling runtime PM for inactive device with active children\n"); + +out: + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_runtime_enable); + +static void pm_runtime_set_suspended_action(void *data) +{ + pm_runtime_set_suspended(data); +} + +/** + * devm_pm_runtime_set_active_enabled - set_active version of devm_pm_runtime_enable. + * + * @dev: Device to handle. + */ +int devm_pm_runtime_set_active_enabled(struct device *dev) +{ + int err; + + err = pm_runtime_set_active(dev); + if (err) + return err; + + err = devm_add_action_or_reset(dev, pm_runtime_set_suspended_action, dev); + if (err) + return err; + + return devm_pm_runtime_enable(dev); +} +EXPORT_SYMBOL_GPL(devm_pm_runtime_set_active_enabled); + +static void pm_runtime_disable_action(void *data) +{ + pm_runtime_dont_use_autosuspend(data); + pm_runtime_disable(data); +} + +/** + * devm_pm_runtime_enable - devres-enabled version of pm_runtime_enable. + * + * NOTE: this will also handle calling pm_runtime_dont_use_autosuspend() for + * you at driver exit time if needed. + * + * @dev: Device to handle. + */ +int devm_pm_runtime_enable(struct device *dev) +{ + pm_runtime_enable(dev); + + return devm_add_action_or_reset(dev, pm_runtime_disable_action, dev); +} +EXPORT_SYMBOL_GPL(devm_pm_runtime_enable); + +static void pm_runtime_put_noidle_action(void *data) +{ + pm_runtime_put_noidle(data); +} + +/** + * devm_pm_runtime_get_noresume - devres-enabled version of pm_runtime_get_noresume. + * + * @dev: Device to handle. + */ +int devm_pm_runtime_get_noresume(struct device *dev) +{ + pm_runtime_get_noresume(dev); + + return devm_add_action_or_reset(dev, pm_runtime_put_noidle_action, dev); +} +EXPORT_SYMBOL_GPL(devm_pm_runtime_get_noresume); + +/** + * pm_runtime_forbid - Block runtime PM of a device. + * @dev: Device to handle. + * + * Resume @dev if already suspended and block runtime suspend of @dev in such + * a way that it can be unblocked via the /sys/devices/.../power/control + * interface, or otherwise by calling pm_runtime_allow(). + * + * Calling this function many times in a row has the same effect as calling it + * once. + */ +void pm_runtime_forbid(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + if (!dev->power.runtime_auto) + goto out; + + dev->power.runtime_auto = false; + atomic_inc(&dev->power.usage_count); + rpm_resume(dev, 0); + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_forbid); + +/** + * pm_runtime_allow - Unblock runtime PM of a device. + * @dev: Device to handle. + * + * Unblock runtime suspend of @dev after it has been blocked by + * pm_runtime_forbid() (for instance, if it has been blocked via the + * /sys/devices/.../power/control interface), check if @dev can be + * suspended and suspend it in that case. + * + * Calling this function many times in a row has the same effect as calling it + * once. + */ +void pm_runtime_allow(struct device *dev) +{ + int ret; + + spin_lock_irq(&dev->power.lock); + if (dev->power.runtime_auto) + goto out; + + dev->power.runtime_auto = true; + ret = rpm_drop_usage_count(dev); + if (ret == 0) + rpm_idle(dev, RPM_AUTO | RPM_ASYNC); + else if (ret > 0) + trace_rpm_usage(dev, RPM_AUTO | RPM_ASYNC); + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_allow); + +/** + * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device. + * @dev: Device to handle. + * + * Set the power.no_callbacks flag, which tells the PM core that this + * device is power-managed through its parent and has no runtime PM + * callbacks of its own. The runtime sysfs attributes will be removed. + */ +void pm_runtime_no_callbacks(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + dev->power.no_callbacks = 1; + spin_unlock_irq(&dev->power.lock); + if (device_is_registered(dev)) + rpm_sysfs_remove(dev); +} +EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); + +/** + * pm_runtime_irq_safe - Leave interrupts disabled during callbacks. + * @dev: Device to handle + * + * Set the power.irq_safe flag, which tells the PM core that the + * ->runtime_suspend() and ->runtime_resume() callbacks for this device should + * always be invoked with the spinlock held and interrupts disabled. It also + * causes the parent's usage counter to be permanently incremented, preventing + * the parent from runtime suspending -- otherwise an irq-safe child might have + * to wait for a non-irq-safe parent. + */ +void pm_runtime_irq_safe(struct device *dev) +{ + if (dev->parent) + pm_runtime_get_sync(dev->parent); + + spin_lock_irq(&dev->power.lock); + dev->power.irq_safe = 1; + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_irq_safe); + +/** + * update_autosuspend - Handle a change to a device's autosuspend settings. + * @dev: Device to handle. + * @old_delay: The former autosuspend_delay value. + * @old_use: The former use_autosuspend value. + * + * Prevent runtime suspend if the new delay is negative and use_autosuspend is + * set; otherwise allow it. Send an idle notification if suspends are allowed. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static void update_autosuspend(struct device *dev, int old_delay, int old_use) +{ + int delay = dev->power.autosuspend_delay; + + /* Should runtime suspend be prevented now? */ + if (dev->power.use_autosuspend && delay < 0) { + + /* If it used to be allowed then prevent it. */ + if (!old_use || old_delay >= 0) { + atomic_inc(&dev->power.usage_count); + rpm_resume(dev, 0); + } else { + trace_rpm_usage(dev, 0); + } + } + + /* Runtime suspend should be allowed now. */ + else { + + /* If it used to be prevented then allow it. */ + if (old_use && old_delay < 0) + atomic_dec(&dev->power.usage_count); + + /* Maybe we can autosuspend now. */ + rpm_idle(dev, RPM_AUTO); + } +} + +/** + * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value. + * @dev: Device to handle. + * @delay: Value of the new delay in milliseconds. + * + * Set the device's power.autosuspend_delay value. If it changes to negative + * and the power.use_autosuspend flag is set, prevent runtime suspends. If it + * changes the other way, allow runtime suspends. + */ +void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) +{ + int old_delay, old_use; + + spin_lock_irq(&dev->power.lock); + old_delay = dev->power.autosuspend_delay; + old_use = dev->power.use_autosuspend; + dev->power.autosuspend_delay = delay; + update_autosuspend(dev, old_delay, old_use); + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay); + +/** + * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag. + * @dev: Device to handle. + * @use: New value for use_autosuspend. + * + * Set the device's power.use_autosuspend flag, and allow or prevent runtime + * suspends as needed. + */ +void __pm_runtime_use_autosuspend(struct device *dev, bool use) +{ + int old_delay, old_use; + + spin_lock_irq(&dev->power.lock); + old_delay = dev->power.autosuspend_delay; + old_use = dev->power.use_autosuspend; + dev->power.use_autosuspend = use; + update_autosuspend(dev, old_delay, old_use); + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend); + +/** + * pm_runtime_init - Initialize runtime PM fields in given device object. + * @dev: Device object to initialize. + */ +void pm_runtime_init(struct device *dev) +{ + dev->power.runtime_status = RPM_SUSPENDED; + dev->power.last_status = RPM_INVALID; + dev->power.idle_notification = false; + + dev->power.disable_depth = 1; + atomic_set(&dev->power.usage_count, 0); + + dev->power.runtime_error = 0; + + atomic_set(&dev->power.child_count, 0); + pm_suspend_ignore_children(dev, false); + dev->power.runtime_auto = true; + + dev->power.request_pending = false; + dev->power.request = RPM_REQ_NONE; + dev->power.deferred_resume = false; + dev->power.needs_force_resume = false; + INIT_WORK(&dev->power.work, pm_runtime_work); + + dev->power.timer_expires = 0; + hrtimer_setup(&dev->power.suspend_timer, pm_suspend_timer_fn, CLOCK_MONOTONIC, + HRTIMER_MODE_ABS); + + init_waitqueue_head(&dev->power.wait_queue); +} + +/** + * pm_runtime_reinit - Re-initialize runtime PM fields in given device object. + * @dev: Device object to re-initialize. + */ +void pm_runtime_reinit(struct device *dev) +{ + if (pm_runtime_enabled(dev)) + return; + + if (dev->power.runtime_status == RPM_ACTIVE) + pm_runtime_set_suspended(dev); + + if (dev->power.irq_safe) { + spin_lock_irq(&dev->power.lock); + dev->power.irq_safe = 0; + spin_unlock_irq(&dev->power.lock); + if (dev->parent) + pm_runtime_put(dev->parent); + } + /* + * Clear power.needs_force_resume in case it has been set by + * pm_runtime_force_suspend() invoked from a driver remove callback. + */ + dev->power.needs_force_resume = false; +} + +/** + * pm_runtime_remove - Prepare for removing a device from device hierarchy. + * @dev: Device object being removed from device hierarchy. + */ +void pm_runtime_remove(struct device *dev) +{ + __pm_runtime_disable(dev, false); + flush_work(&dev->power.work); + pm_runtime_reinit(dev); +} + +/** + * pm_runtime_get_suppliers - Resume and reference-count supplier devices. + * @dev: Consumer device. + */ +void pm_runtime_get_suppliers(struct device *dev) +{ + struct device_link *link; + int idx; + + idx = device_links_read_lock(); + + dev_for_each_link_to_supplier(link, dev) + if (device_link_test(link, DL_FLAG_PM_RUNTIME)) { + link->supplier_preactivated = true; + pm_runtime_get_sync(link->supplier); + } + + device_links_read_unlock(idx); +} + +/** + * pm_runtime_put_suppliers - Drop references to supplier devices. + * @dev: Consumer device. + */ +void pm_runtime_put_suppliers(struct device *dev) +{ + struct device_link *link; + int idx; + + idx = device_links_read_lock(); + + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) + if (link->supplier_preactivated) { + link->supplier_preactivated = false; + pm_runtime_put(link->supplier); + } + + device_links_read_unlock(idx); +} + +void pm_runtime_new_link(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + dev->power.links_count++; + spin_unlock_irq(&dev->power.lock); +} + +static void pm_runtime_drop_link_count(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + WARN_ON(dev->power.links_count == 0); + dev->power.links_count--; + spin_unlock_irq(&dev->power.lock); +} + +/** + * pm_runtime_drop_link - Prepare for device link removal. + * @link: Device link going away. + * + * Drop the link count of the consumer end of @link and decrement the supplier + * device's runtime PM usage counter as many times as needed to drop all of the + * PM runtime reference to it from the consumer. + */ +void pm_runtime_drop_link(struct device_link *link) +{ + if (!device_link_test(link, DL_FLAG_PM_RUNTIME)) + return; + + pm_runtime_drop_link_count(link->consumer); + pm_runtime_release_supplier(link); + pm_request_idle(link->supplier); +} + +static pm_callback_t get_callback(struct device *dev, size_t cb_offset) +{ + /* + * Setting power.strict_midlayer means that the middle layer + * code does not want its runtime PM callbacks to be invoked via + * pm_runtime_force_suspend() and pm_runtime_force_resume(), so + * return a direct pointer to the driver callback in that case. + */ + if (dev_pm_strict_midlayer_is_set(dev)) + return __rpm_get_driver_callback(dev, cb_offset); + + return __rpm_get_callback(dev, cb_offset); +} + +#define GET_CALLBACK(dev, callback) \ + get_callback(dev, offsetof(struct dev_pm_ops, callback)) + +/** + * pm_runtime_force_suspend - Force a device into suspend state if needed. + * @dev: Device to suspend. + * + * Disable runtime PM so we safely can check the device's runtime PM status and + * if it is active, invoke its ->runtime_suspend callback to suspend it and + * change its runtime PM status field to RPM_SUSPENDED. Also, if the device's + * usage and children counters don't indicate that the device was in use before + * the system-wide transition under way, decrement its parent's children counter + * (if there is a parent). Keep runtime PM disabled to preserve the state + * unless we encounter errors. + * + * Typically this function may be invoked from a system suspend callback to make + * sure the device is put into low power state and it should only be used during + * system-wide PM transitions to sleep states. It assumes that the analogous + * pm_runtime_force_resume() will be used to resume the device. + */ +int pm_runtime_force_suspend(struct device *dev) +{ + int (*callback)(struct device *); + int ret; + + pm_runtime_disable(dev); + if (pm_runtime_status_suspended(dev) || dev->power.needs_force_resume) + return 0; + + callback = GET_CALLBACK(dev, runtime_suspend); + + dev_pm_enable_wake_irq_check(dev, true); + ret = callback ? callback(dev) : 0; + if (ret) + goto err; + + dev_pm_enable_wake_irq_complete(dev); + + /* + * If the device can stay in suspend after the system-wide transition + * to the working state that will follow, drop the children counter of + * its parent and the usage counters of its suppliers. Otherwise, set + * power.needs_force_resume to let pm_runtime_force_resume() know that + * the device needs to be taken care of and to prevent this function + * from handling the device again in case the device is passed to it + * once more subsequently. + */ + if (pm_runtime_need_not_resume(dev)) + pm_runtime_set_suspended(dev); + else + dev->power.needs_force_resume = true; + + return 0; + +err: + dev_pm_disable_wake_irq_check(dev, true); + pm_runtime_enable(dev); + return ret; +} +EXPORT_SYMBOL_GPL(pm_runtime_force_suspend); + +#ifdef CONFIG_PM_SLEEP + +/** + * pm_runtime_force_resume - Force a device into resume state if needed. + * @dev: Device to resume. + * + * This function expects that either pm_runtime_force_suspend() has put the + * device into a low-power state prior to calling it, or the device had been + * runtime-suspended before the preceding system-wide suspend transition and it + * was left in suspend during that transition. + * + * The actions carried out by pm_runtime_force_suspend(), or by a runtime + * suspend in general, are reversed and the device is brought back into full + * power if it is expected to be used on system resume, which is the case when + * its needs_force_resume flag is set or when its smart_suspend flag is set and + * its runtime PM status is "active". + * + * In other cases, the resume is deferred to be managed via runtime PM. + * + * Typically, this function may be invoked from a system resume callback. + */ +int pm_runtime_force_resume(struct device *dev) +{ + int (*callback)(struct device *); + int ret = 0; + + if (!dev->power.needs_force_resume && (!dev_pm_smart_suspend(dev) || + pm_runtime_status_suspended(dev))) + goto out; + + callback = GET_CALLBACK(dev, runtime_resume); + + dev_pm_disable_wake_irq_check(dev, false); + ret = callback ? callback(dev) : 0; + if (ret) { + pm_runtime_set_suspended(dev); + dev_pm_enable_wake_irq_check(dev, false); + goto out; + } + + pm_runtime_mark_last_busy(dev); + +out: + /* + * The smart_suspend flag can be cleared here because it is not going + * to be necessary until the next system-wide suspend transition that + * will update it again. + */ + dev->power.smart_suspend = false; + /* + * Also clear needs_force_resume to make this function skip devices that + * have been seen by it once. + */ + dev->power.needs_force_resume = false; + + pm_runtime_enable(dev); + return ret; +} +EXPORT_SYMBOL_GPL(pm_runtime_force_resume); + +bool pm_runtime_need_not_resume(struct device *dev) +{ + return atomic_read(&dev->power.usage_count) <= 1 && + (atomic_read(&dev->power.child_count) == 0 || + dev->power.ignore_children); +} + +#endif /* CONFIG_PM_SLEEP */ diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c new file mode 100644 index 000000000..13b31a3ad --- /dev/null +++ b/drivers/base/power/sysfs.c @@ -0,0 +1,835 @@ +// SPDX-License-Identifier: GPL-2.0 +/* sysfs entries for device PM */ +#include <linux/device.h> +#include <linux/kobject.h> +#include <linux/string.h> +#include <linux/export.h> +#include <linux/pm_qos.h> +#include <linux/pm_runtime.h> +#include <linux/atomic.h> +#include <linux/jiffies.h> +#include "power.h" + +/* + * control - Report/change current runtime PM setting of the device + * + * Runtime power management of a device can be blocked with the help of + * this attribute. All devices have one of the following two values for + * the power/control file: + * + * + "auto\n" to allow the device to be power managed at run time; + * + "on\n" to prevent the device from being power managed at run time; + * + * The default for all devices is "auto", which means that devices may be + * subject to automatic power management, depending on their drivers. + * Changing this attribute to "on" prevents the driver from power managing + * the device at run time. Doing that while the device is suspended causes + * it to be woken up. + * + * wakeup - Report/change current wakeup option for device + * + * Some devices support "wakeup" events, which are hardware signals + * used to activate devices from suspended or low power states. Such + * devices have one of three values for the sysfs power/wakeup file: + * + * + "enabled\n" to issue the events; + * + "disabled\n" not to do so; or + * + "\n" for temporary or permanent inability to issue wakeup. + * + * (For example, unconfigured USB devices can't issue wakeups.) + * + * Familiar examples of devices that can issue wakeup events include + * keyboards and mice (both PS2 and USB styles), power buttons, modems, + * "Wake-On-LAN" Ethernet links, GPIO lines, and more. Some events + * will wake the entire system from a suspend state; others may just + * wake up the device (if the system as a whole is already active). + * Some wakeup events use normal IRQ lines; other use special out + * of band signaling. + * + * It is the responsibility of device drivers to enable (or disable) + * wakeup signaling as part of changing device power states, respecting + * the policy choices provided through the driver model. + * + * Devices may not be able to generate wakeup events from all power + * states. Also, the events may be ignored in some configurations; + * for example, they might need help from other devices that aren't + * active, or which may have wakeup disabled. Some drivers rely on + * wakeup events internally (unless they are disabled), keeping + * their hardware in low power modes whenever they're unused. This + * saves runtime power, without requiring system-wide sleep states. + * + * async - Report/change current async suspend setting for the device + * + * Asynchronous suspend and resume of the device during system-wide power + * state transitions can be enabled by writing "enabled" to this file. + * Analogously, if "disabled" is written to this file, the device will be + * suspended and resumed synchronously. + * + * All devices have one of the following two values for power/async: + * + * + "enabled\n" to permit the asynchronous suspend/resume of the device; + * + "disabled\n" to forbid it; + * + * NOTE: It generally is unsafe to permit the asynchronous suspend/resume + * of a device unless it is certain that all of the PM dependencies of the + * device are known to the PM core. However, for some devices this + * attribute is set to "enabled" by bus type code or device drivers and in + * that cases it should be safe to leave the default value. + * + * autosuspend_delay_ms - Report/change a device's autosuspend_delay value + * + * Some drivers don't want to carry out a runtime suspend as soon as a + * device becomes idle; they want it always to remain idle for some period + * of time before suspending it. This period is the autosuspend_delay + * value (expressed in milliseconds) and it can be controlled by the user. + * If the value is negative then the device will never be runtime + * suspended. + * + * NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay + * value are used only if the driver calls pm_runtime_use_autosuspend(). + * + * wakeup_count - Report the number of wakeup events related to the device + */ + +const char power_group_name[] = "power"; +EXPORT_SYMBOL_GPL(power_group_name); + +static const char ctrl_auto[] = "auto"; +static const char ctrl_on[] = "on"; + +static ssize_t control_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%s\n", + dev->power.runtime_auto ? ctrl_auto : ctrl_on); +} + +static ssize_t control_store(struct device * dev, struct device_attribute *attr, + const char * buf, size_t n) +{ + device_lock(dev); + if (sysfs_streq(buf, ctrl_auto)) + pm_runtime_allow(dev); + else if (sysfs_streq(buf, ctrl_on)) + pm_runtime_forbid(dev); + else + n = -EINVAL; + device_unlock(dev); + return n; +} + +static DEVICE_ATTR_RW(control); + +static ssize_t runtime_active_time_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + u64 tmp = pm_runtime_active_time(dev); + + do_div(tmp, NSEC_PER_MSEC); + + return sysfs_emit(buf, "%llu\n", tmp); +} + +static DEVICE_ATTR_RO(runtime_active_time); + +static ssize_t runtime_suspended_time_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + u64 tmp = pm_runtime_suspended_time(dev); + + do_div(tmp, NSEC_PER_MSEC); + + return sysfs_emit(buf, "%llu\n", tmp); +} + +static DEVICE_ATTR_RO(runtime_suspended_time); + +static ssize_t runtime_status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const char *output; + + if (dev->power.runtime_error) { + output = "error"; + } else if (dev->power.disable_depth) { + output = "unsupported"; + } else { + switch (dev->power.runtime_status) { + case RPM_SUSPENDED: + output = "suspended"; + break; + case RPM_SUSPENDING: + output = "suspending"; + break; + case RPM_RESUMING: + output = "resuming"; + break; + case RPM_ACTIVE: + output = "active"; + break; + default: + return -EIO; + } + } + return sysfs_emit(buf, "%s\n", output); +} + +static DEVICE_ATTR_RO(runtime_status); + +static ssize_t autosuspend_delay_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + if (!dev->power.use_autosuspend) + return -EIO; + + return sysfs_emit(buf, "%d\n", dev->power.autosuspend_delay); +} + +static ssize_t autosuspend_delay_ms_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t n) +{ + long delay; + + if (!dev->power.use_autosuspend) + return -EIO; + + if (kstrtol(buf, 10, &delay) != 0 || delay != (int) delay) + return -EINVAL; + + device_lock(dev); + pm_runtime_set_autosuspend_delay(dev, delay); + device_unlock(dev); + return n; +} + +static DEVICE_ATTR_RW(autosuspend_delay_ms); + +static ssize_t pm_qos_resume_latency_us_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s32 value = dev_pm_qos_requested_resume_latency(dev); + + if (value == 0) + return sysfs_emit(buf, "n/a\n"); + if (value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT) + value = 0; + + return sysfs_emit(buf, "%d\n", value); +} + +static ssize_t pm_qos_resume_latency_us_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t n) +{ + s32 value; + int ret; + + if (!kstrtos32(buf, 0, &value)) { + /* + * Prevent users from writing negative or "no constraint" values + * directly. + */ + if (value < 0 || value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT) + return -EINVAL; + + if (value == 0) + value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT; + } else if (sysfs_streq(buf, "n/a")) { + value = 0; + } else { + return -EINVAL; + } + + ret = dev_pm_qos_update_request(dev->power.qos->resume_latency_req, + value); + return ret < 0 ? ret : n; +} + +static DEVICE_ATTR_RW(pm_qos_resume_latency_us); + +static ssize_t pm_qos_latency_tolerance_us_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s32 value = dev_pm_qos_get_user_latency_tolerance(dev); + + if (value < 0) + return sysfs_emit(buf, "%s\n", "auto"); + if (value == PM_QOS_LATENCY_ANY) + return sysfs_emit(buf, "%s\n", "any"); + + return sysfs_emit(buf, "%d\n", value); +} + +static ssize_t pm_qos_latency_tolerance_us_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t n) +{ + s32 value; + int ret; + + if (kstrtos32(buf, 0, &value) == 0) { + /* Users can't write negative values directly */ + if (value < 0) + return -EINVAL; + } else { + if (sysfs_streq(buf, "auto")) + value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; + else if (sysfs_streq(buf, "any")) + value = PM_QOS_LATENCY_ANY; + else + return -EINVAL; + } + ret = dev_pm_qos_update_user_latency_tolerance(dev, value); + return ret < 0 ? ret : n; +} + +static DEVICE_ATTR_RW(pm_qos_latency_tolerance_us); + +static ssize_t pm_qos_no_power_off_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev) + & PM_QOS_FLAG_NO_POWER_OFF)); +} + +static ssize_t pm_qos_no_power_off_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t n) +{ + int ret; + + if (kstrtoint(buf, 0, &ret)) + return -EINVAL; + + if (ret != 0 && ret != 1) + return -EINVAL; + + ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_NO_POWER_OFF, ret); + return ret < 0 ? ret : n; +} + +static DEVICE_ATTR_RW(pm_qos_no_power_off); + +#ifdef CONFIG_PM_SLEEP +static const char _enabled[] = "enabled"; +static const char _disabled[] = "disabled"; + +static ssize_t wakeup_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%s\n", device_can_wakeup(dev) + ? (device_may_wakeup(dev) ? _enabled : _disabled) + : ""); +} + +static ssize_t wakeup_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t n) +{ + if (!device_can_wakeup(dev)) + return -EINVAL; + + if (sysfs_streq(buf, _enabled)) + device_set_wakeup_enable(dev, 1); + else if (sysfs_streq(buf, _disabled)) + device_set_wakeup_enable(dev, 0); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR_RW(wakeup); + +static ssize_t wakeup_count_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned long count; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->wakeup_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%lu\n", count); +} + +static DEVICE_ATTR_RO(wakeup_count); + +static ssize_t wakeup_active_count_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + unsigned long count; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->active_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%lu\n", count); +} + +static DEVICE_ATTR_RO(wakeup_active_count); + +static ssize_t wakeup_abort_count_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + unsigned long count; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->wakeup_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%lu\n", count); +} + +static DEVICE_ATTR_RO(wakeup_abort_count); + +static ssize_t wakeup_expire_count_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + unsigned long count; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->expire_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%lu\n", count); +} + +static DEVICE_ATTR_RO(wakeup_expire_count); + +static ssize_t wakeup_active_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned int active; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + active = dev->power.wakeup->active; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%u\n", active); +} + +static DEVICE_ATTR_RO(wakeup_active); + +static ssize_t wakeup_total_time_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s64 msec; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->total_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%lld\n", msec); +} + +static DEVICE_ATTR_RO(wakeup_total_time_ms); + +static ssize_t wakeup_max_time_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + s64 msec; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->max_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%lld\n", msec); +} + +static DEVICE_ATTR_RO(wakeup_max_time_ms); + +static ssize_t wakeup_last_time_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s64 msec; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->last_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%lld\n", msec); +} + +static DEVICE_ATTR_RO(wakeup_last_time_ms); + +#ifdef CONFIG_PM_AUTOSLEEP +static ssize_t wakeup_prevent_sleep_time_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s64 msec; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + + if (!enabled) + return sysfs_emit(buf, "\n"); + return sysfs_emit(buf, "%lld\n", msec); +} + +static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms); +#endif /* CONFIG_PM_AUTOSLEEP */ + +static inline int dpm_sysfs_wakeup_change_owner(struct device *dev, kuid_t kuid, + kgid_t kgid) +{ + if (dev->power.wakeup && dev->power.wakeup->dev) + return device_change_owner(dev->power.wakeup->dev, kuid, kgid); + return 0; +} + +#else /* CONFIG_PM_SLEEP */ +static inline int dpm_sysfs_wakeup_change_owner(struct device *dev, kuid_t kuid, + kgid_t kgid) +{ + return 0; +} +#endif + +#ifdef CONFIG_PM_ADVANCED_DEBUG +static ssize_t runtime_usage_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%d\n", atomic_read(&dev->power.usage_count)); +} +static DEVICE_ATTR_RO(runtime_usage); + +static ssize_t runtime_active_kids_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%d\n", dev->power.ignore_children ? + 0 : atomic_read(&dev->power.child_count)); +} +static DEVICE_ATTR_RO(runtime_active_kids); + +static ssize_t runtime_enabled_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const char *output; + + if (dev->power.disable_depth && !dev->power.runtime_auto) + output = "disabled & forbidden"; + else if (dev->power.disable_depth) + output = "disabled"; + else if (!dev->power.runtime_auto) + output = "forbidden"; + else + output = "enabled"; + + return sysfs_emit(buf, "%s\n", output); +} +static DEVICE_ATTR_RO(runtime_enabled); + +#ifdef CONFIG_PM_SLEEP +static ssize_t async_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%s\n", + device_async_suspend_enabled(dev) ? + _enabled : _disabled); +} + +static ssize_t async_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t n) +{ + if (sysfs_streq(buf, _enabled)) + device_enable_async_suspend(dev); + else if (sysfs_streq(buf, _disabled)) + device_disable_async_suspend(dev); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR_RW(async); + +#endif /* CONFIG_PM_SLEEP */ +#endif /* CONFIG_PM_ADVANCED_DEBUG */ + +static struct attribute *power_attrs[] = { +#if defined(CONFIG_PM_ADVANCED_DEBUG) && defined(CONFIG_PM_SLEEP) + &dev_attr_async.attr, +#endif + NULL, +}; +static const struct attribute_group pm_attr_group = { + .name = power_group_name, + .attrs = power_attrs, +}; + +static struct attribute *wakeup_attrs[] = { +#ifdef CONFIG_PM_SLEEP + &dev_attr_wakeup.attr, + &dev_attr_wakeup_count.attr, + &dev_attr_wakeup_active_count.attr, + &dev_attr_wakeup_abort_count.attr, + &dev_attr_wakeup_expire_count.attr, + &dev_attr_wakeup_active.attr, + &dev_attr_wakeup_total_time_ms.attr, + &dev_attr_wakeup_max_time_ms.attr, + &dev_attr_wakeup_last_time_ms.attr, +#ifdef CONFIG_PM_AUTOSLEEP + &dev_attr_wakeup_prevent_sleep_time_ms.attr, +#endif +#endif + NULL, +}; +static const struct attribute_group pm_wakeup_attr_group = { + .name = power_group_name, + .attrs = wakeup_attrs, +}; + +static struct attribute *runtime_attrs[] = { + &dev_attr_runtime_status.attr, + &dev_attr_control.attr, + &dev_attr_runtime_suspended_time.attr, + &dev_attr_runtime_active_time.attr, + &dev_attr_autosuspend_delay_ms.attr, +#ifdef CONFIG_PM_ADVANCED_DEBUG + &dev_attr_runtime_usage.attr, + &dev_attr_runtime_active_kids.attr, + &dev_attr_runtime_enabled.attr, +#endif + NULL, +}; +static const struct attribute_group pm_runtime_attr_group = { + .name = power_group_name, + .attrs = runtime_attrs, +}; + +static struct attribute *pm_qos_resume_latency_attrs[] = { + &dev_attr_pm_qos_resume_latency_us.attr, + NULL, +}; +static const struct attribute_group pm_qos_resume_latency_attr_group = { + .name = power_group_name, + .attrs = pm_qos_resume_latency_attrs, +}; + +static struct attribute *pm_qos_latency_tolerance_attrs[] = { + &dev_attr_pm_qos_latency_tolerance_us.attr, + NULL, +}; +static const struct attribute_group pm_qos_latency_tolerance_attr_group = { + .name = power_group_name, + .attrs = pm_qos_latency_tolerance_attrs, +}; + +static struct attribute *pm_qos_flags_attrs[] = { + &dev_attr_pm_qos_no_power_off.attr, + NULL, +}; +static const struct attribute_group pm_qos_flags_attr_group = { + .name = power_group_name, + .attrs = pm_qos_flags_attrs, +}; + +int dpm_sysfs_add(struct device *dev) +{ + int rc; + + /* No need to create PM sysfs if explicitly disabled. */ + if (device_pm_not_required(dev)) + return 0; + + rc = sysfs_create_group(&dev->kobj, &pm_attr_group); + if (rc) + return rc; + + if (!pm_runtime_has_no_callbacks(dev)) { + rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group); + if (rc) + goto err_out; + } + if (device_can_wakeup(dev)) { + rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group); + if (rc) + goto err_runtime; + } + if (dev->power.set_latency_tolerance) { + rc = sysfs_merge_group(&dev->kobj, + &pm_qos_latency_tolerance_attr_group); + if (rc) + goto err_wakeup; + } + rc = pm_wakeup_source_sysfs_add(dev); + if (rc) + goto err_latency; + return 0; + + err_latency: + sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group); + err_wakeup: + sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); + err_runtime: + sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group); + err_out: + sysfs_remove_group(&dev->kobj, &pm_attr_group); + return rc; +} + +int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid) +{ + int rc; + + if (device_pm_not_required(dev)) + return 0; + + rc = sysfs_group_change_owner(&dev->kobj, &pm_attr_group, kuid, kgid); + if (rc) + return rc; + + if (!pm_runtime_has_no_callbacks(dev)) { + rc = sysfs_group_change_owner( + &dev->kobj, &pm_runtime_attr_group, kuid, kgid); + if (rc) + return rc; + } + + if (device_can_wakeup(dev)) { + rc = sysfs_group_change_owner(&dev->kobj, &pm_wakeup_attr_group, + kuid, kgid); + if (rc) + return rc; + + rc = dpm_sysfs_wakeup_change_owner(dev, kuid, kgid); + if (rc) + return rc; + } + + if (dev->power.set_latency_tolerance) { + rc = sysfs_group_change_owner( + &dev->kobj, &pm_qos_latency_tolerance_attr_group, kuid, + kgid); + if (rc) + return rc; + } + return 0; +} + +int wakeup_sysfs_add(struct device *dev) +{ + int ret = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group); + + if (!ret) + kobject_uevent(&dev->kobj, KOBJ_CHANGE); + + return ret; +} + +void wakeup_sysfs_remove(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); + kobject_uevent(&dev->kobj, KOBJ_CHANGE); +} + +int pm_qos_sysfs_add_resume_latency(struct device *dev) +{ + return sysfs_merge_group(&dev->kobj, &pm_qos_resume_latency_attr_group); +} + +void pm_qos_sysfs_remove_resume_latency(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_qos_resume_latency_attr_group); +} + +int pm_qos_sysfs_add_flags(struct device *dev) +{ + return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group); +} + +void pm_qos_sysfs_remove_flags(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group); +} + +int pm_qos_sysfs_add_latency_tolerance(struct device *dev) +{ + return sysfs_merge_group(&dev->kobj, + &pm_qos_latency_tolerance_attr_group); +} + +void pm_qos_sysfs_remove_latency_tolerance(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group); +} + +void rpm_sysfs_remove(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group); +} + +void dpm_sysfs_remove(struct device *dev) +{ + if (device_pm_not_required(dev)) + return; + sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group); + dev_pm_qos_constraints_destroy(dev); + rpm_sysfs_remove(dev); + sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); + sysfs_remove_group(&dev->kobj, &pm_attr_group); +} diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c new file mode 100644 index 000000000..d8da7195b --- /dev/null +++ b/drivers/base/power/trace.c @@ -0,0 +1,305 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/trace.c + * + * Copyright (C) 2006 Linus Torvalds + * + * Trace facility for suspend/resume problems, when none of the + * devices may be working. + */ +#define pr_fmt(fmt) "PM: " fmt + +#include <linux/pm-trace.h> +#include <linux/export.h> +#include <linux/rtc.h> +#include <linux/suspend.h> +#include <linux/init.h> + +#include <linux/mc146818rtc.h> + +#include "power.h" + +/* + * Horrid, horrid, horrid. + * + * It turns out that the _only_ piece of hardware that actually + * keeps its value across a hard boot (and, more importantly, the + * POST init sequence) is literally the realtime clock. + * + * Never mind that an RTC chip has 114 bytes (and often a whole + * other bank of an additional 128 bytes) of nice SRAM that is + * _designed_ to keep data - the POST will clear it. So we literally + * can just use the few bytes of actual time data, which means that + * we're really limited. + * + * It means, for example, that we can't use the seconds at all + * (since the time between the hang and the boot might be more + * than a minute), and we'd better not depend on the low bits of + * the minutes either. + * + * There are the wday fields etc, but I wouldn't guarantee those + * are dependable either. And if the date isn't valid, either the + * hw or POST will do strange things. + * + * So we're left with: + * - year: 0-99 + * - month: 0-11 + * - day-of-month: 1-28 + * - hour: 0-23 + * - min: (0-30)*2 + * + * Giving us a total range of 0-16128000 (0xf61800), ie less + * than 24 bits of actual data we can save across reboots. + * + * And if your box can't boot in less than three minutes, + * you're screwed. + * + * Now, almost 24 bits of data is pitifully small, so we need + * to be pretty dense if we want to use it for anything nice. + * What we do is that instead of saving off nice readable info, + * we save off _hashes_ of information that we can hopefully + * regenerate after the reboot. + * + * In particular, this means that we might be unlucky, and hit + * a case where we have a hash collision, and we end up not + * being able to tell for certain exactly which case happened. + * But that's hopefully unlikely. + * + * What we do is to take the bits we can fit, and split them + * into three parts (16*997*1009 = 16095568), and use the values + * for: + * - 0-15: user-settable + * - 0-996: file + line number + * - 0-1008: device + */ +#define USERHASH (16) +#define FILEHASH (997) +#define DEVHASH (1009) + +#define DEVSEED (7919) + +bool pm_trace_rtc_abused __read_mostly; +EXPORT_SYMBOL_GPL(pm_trace_rtc_abused); + +static unsigned int dev_hash_value; + +static int set_magic_time(unsigned int user, unsigned int file, unsigned int device) +{ + unsigned int n = user + USERHASH*(file + FILEHASH*device); + + // June 7th, 2006 + static struct rtc_time time = { + .tm_sec = 0, + .tm_min = 0, + .tm_hour = 0, + .tm_mday = 7, + .tm_mon = 5, // June - counting from zero + .tm_year = 106, + .tm_wday = 3, + .tm_yday = 160, + .tm_isdst = 1 + }; + + time.tm_year = (n % 100); + n /= 100; + time.tm_mon = (n % 12); + n /= 12; + time.tm_mday = (n % 28) + 1; + n /= 28; + time.tm_hour = (n % 24); + n /= 24; + time.tm_min = (n % 20) * 3; + n /= 20; + mc146818_set_time(&time); + pm_trace_rtc_abused = true; + return n ? -1 : 0; +} + +static unsigned int read_magic_time(void) +{ + struct rtc_time time; + unsigned int val; + + if (mc146818_get_time(&time, 1000) < 0) { + pr_err("Unable to read current time from RTC\n"); + return 0; + } + + pr_info("RTC time: %ptRt, date: %ptRd\n", &time, &time); + val = time.tm_year; /* 100 years */ + if (val > 100) + val -= 100; + val += time.tm_mon * 100; /* 12 months */ + val += (time.tm_mday-1) * 100 * 12; /* 28 month-days */ + val += time.tm_hour * 100 * 12 * 28; /* 24 hours */ + val += (time.tm_min / 3) * 100 * 12 * 28 * 24; /* 20 3-minute intervals */ + return val; +} + +/* + * This is just the sdbm hash function with a user-supplied + * seed and final size parameter. + */ +static unsigned int hash_string(unsigned int seed, const char *data, unsigned int mod) +{ + unsigned char c; + while ((c = *data++) != 0) { + seed = (seed << 16) + (seed << 6) - seed + c; + } + return seed % mod; +} + +void set_trace_device(struct device *dev) +{ + dev_hash_value = hash_string(DEVSEED, dev_name(dev), DEVHASH); +} +EXPORT_SYMBOL(set_trace_device); + +/* + * We could just take the "tracedata" index into the .tracedata + * section instead. Generating a hash of the data gives us a + * chance to work across kernel versions, and perhaps more + * importantly it also gives us valid/invalid check (ie we will + * likely not give totally bogus reports - if the hash matches, + * it's not any guarantee, but it's a high _likelihood_ that + * the match is valid). + */ +void generate_pm_trace(const void *tracedata, unsigned int user) +{ + unsigned short lineno = *(unsigned short *)tracedata; + const char *file = *(const char **)(tracedata + 2); + unsigned int user_hash_value, file_hash_value; + + if (!x86_platform.legacy.rtc) + return; + + user_hash_value = user % USERHASH; + file_hash_value = hash_string(lineno, file, FILEHASH); + set_magic_time(user_hash_value, file_hash_value, dev_hash_value); +} +EXPORT_SYMBOL(generate_pm_trace); + +extern char __tracedata_start[], __tracedata_end[]; +static int show_file_hash(unsigned int value) +{ + int match; + char *tracedata; + + match = 0; + for (tracedata = __tracedata_start ; tracedata < __tracedata_end ; + tracedata += 2 + sizeof(unsigned long)) { + unsigned short lineno = *(unsigned short *)tracedata; + const char *file = *(const char **)(tracedata + 2); + unsigned int hash = hash_string(lineno, file, FILEHASH); + if (hash != value) + continue; + pr_info(" hash matches %s:%u\n", file, lineno); + match++; + } + return match; +} + +static int show_dev_hash(unsigned int value) +{ + int match = 0; + struct list_head *entry; + + device_pm_lock(); + entry = dpm_list.prev; + while (entry != &dpm_list) { + struct device * dev = to_device(entry); + unsigned int hash = hash_string(DEVSEED, dev_name(dev), DEVHASH); + if (hash == value) { + dev_info(dev, "hash matches\n"); + match++; + } + entry = entry->prev; + } + device_pm_unlock(); + return match; +} + +static unsigned int hash_value_early_read; + +int show_trace_dev_match(char *buf, size_t size) +{ + unsigned int value = hash_value_early_read / (USERHASH * FILEHASH); + int ret = 0; + struct list_head *entry; + + /* + * It's possible that multiple devices will match the hash and we can't + * tell which is the culprit, so it's best to output them all. + */ + device_pm_lock(); + entry = dpm_list.prev; + while (size && entry != &dpm_list) { + struct device *dev = to_device(entry); + unsigned int hash = hash_string(DEVSEED, dev_name(dev), + DEVHASH); + if (hash == value) { + int len = scnprintf(buf, size, "%s\n", + dev_driver_string(dev)); + buf += len; + ret += len; + size -= len; + } + entry = entry->prev; + } + device_pm_unlock(); + return ret; +} + +static int +pm_trace_notify(struct notifier_block *nb, unsigned long mode, void *_unused) +{ + switch (mode) { + case PM_POST_HIBERNATION: + case PM_POST_SUSPEND: + if (pm_trace_rtc_abused) { + pm_trace_rtc_abused = false; + pr_warn("Possible incorrect RTC due to pm_trace, please use 'ntpdate' or 'rdate' to reset it.\n"); + } + break; + default: + break; + } + return 0; +} + +static struct notifier_block pm_trace_nb = { + .notifier_call = pm_trace_notify, +}; + +static int __init early_resume_init(void) +{ + if (!x86_platform.legacy.rtc) + return 0; + + hash_value_early_read = read_magic_time(); + register_pm_notifier(&pm_trace_nb); + return 0; +} + +static int __init late_resume_init(void) +{ + unsigned int val = hash_value_early_read; + unsigned int user, file, dev; + + if (!x86_platform.legacy.rtc) + return 0; + + user = val % USERHASH; + val = val / USERHASH; + file = val % FILEHASH; + val = val / FILEHASH; + dev = val /* % DEVHASH */; + + pr_info(" Magic number: %d:%d:%d\n", user, file, dev); + show_file_hash(file); + show_dev_hash(dev); + return 0; +} + +core_initcall(early_resume_init); +late_initcall(late_resume_init); diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c new file mode 100644 index 000000000..ad23f0fa5 --- /dev/null +++ b/drivers/base/power/wakeirq.c @@ -0,0 +1,394 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Device wakeirq helper functions */ +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/slab.h> +#include <linux/pm_runtime.h> +#include <linux/pm_wakeirq.h> + +#include "power.h" + +/** + * dev_pm_attach_wake_irq - Attach device interrupt as a wake IRQ + * @dev: Device entry + * @wirq: Wake irq specific data + * + * Internal function to attach a dedicated wake-up interrupt as a wake IRQ. + */ +static int dev_pm_attach_wake_irq(struct device *dev, struct wake_irq *wirq) +{ + unsigned long flags; + + if (!dev || !wirq) + return -EINVAL; + + spin_lock_irqsave(&dev->power.lock, flags); + if (dev_WARN_ONCE(dev, dev->power.wakeirq, + "wake irq already initialized\n")) { + spin_unlock_irqrestore(&dev->power.lock, flags); + return -EEXIST; + } + + dev->power.wakeirq = wirq; + device_wakeup_attach_irq(dev, wirq); + + spin_unlock_irqrestore(&dev->power.lock, flags); + return 0; +} + +/** + * dev_pm_set_wake_irq - Attach device IO interrupt as wake IRQ + * @dev: Device entry + * @irq: Device IO interrupt + * + * Attach a device IO interrupt as a wake IRQ. The wake IRQ gets + * automatically configured for wake-up from suspend based + * on the device specific sysfs wakeup entry. Typically called + * during driver probe after calling device_init_wakeup(). + */ +int dev_pm_set_wake_irq(struct device *dev, int irq) +{ + struct wake_irq *wirq; + int err; + + if (irq < 0) + return -EINVAL; + + wirq = kzalloc_obj(*wirq); + if (!wirq) + return -ENOMEM; + + wirq->dev = dev; + wirq->irq = irq; + + err = dev_pm_attach_wake_irq(dev, wirq); + if (err) + kfree(wirq); + + return err; +} +EXPORT_SYMBOL_GPL(dev_pm_set_wake_irq); + +/** + * dev_pm_clear_wake_irq - Detach a device IO interrupt wake IRQ + * @dev: Device entry + * + * Detach a device wake IRQ and free resources. + * + * Note that it's OK for drivers to call this without calling + * dev_pm_set_wake_irq() as all the driver instances may not have + * a wake IRQ configured. This avoid adding wake IRQ specific + * checks into the drivers. + */ +void dev_pm_clear_wake_irq(struct device *dev) +{ + struct wake_irq *wirq; + unsigned long flags; + + spin_lock_irqsave(&dev->power.lock, flags); + wirq = dev->power.wakeirq; + if (!wirq) { + spin_unlock_irqrestore(&dev->power.lock, flags); + return; + } + + device_wakeup_detach_irq(dev); + dev->power.wakeirq = NULL; + spin_unlock_irqrestore(&dev->power.lock, flags); + + if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED) { + free_irq(wirq->irq, wirq); + wirq->status &= ~WAKE_IRQ_DEDICATED_MASK; + } + kfree(wirq->name); + kfree(wirq); +} +EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq); + +static void devm_pm_clear_wake_irq(void *dev) +{ + dev_pm_clear_wake_irq(dev); +} + +/** + * devm_pm_set_wake_irq - device-managed variant of dev_pm_set_wake_irq + * @dev: Device entry + * @irq: Device IO interrupt + * + * + * Attach a device IO interrupt as a wake IRQ, same with dev_pm_set_wake_irq, + * but the device will be auto clear wake capability on driver detach. + */ +int devm_pm_set_wake_irq(struct device *dev, int irq) +{ + int ret; + + ret = dev_pm_set_wake_irq(dev, irq); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, devm_pm_clear_wake_irq, dev); +} +EXPORT_SYMBOL_GPL(devm_pm_set_wake_irq); + +/** + * handle_threaded_wake_irq - Handler for dedicated wake-up interrupts + * @irq: Device specific dedicated wake-up interrupt + * @_wirq: Wake IRQ data + * + * Some devices have a separate wake-up interrupt in addition to the + * device IO interrupt. The wake-up interrupt signals that a device + * should be woken up from it's idle state. This handler uses device + * specific pm_runtime functions to wake the device, and then it's + * up to the device to do whatever it needs to. Note that as the + * device may need to restore context and start up regulators, we + * use a threaded IRQ. + * + * Also note that we are not resending the lost device interrupts. + * We assume that the wake-up interrupt just needs to wake-up the + * device, and then device's pm_runtime_resume() can deal with the + * situation. + */ +static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq) +{ + struct wake_irq *wirq = _wirq; + int res; + + /* Maybe abort suspend? */ + if (irqd_is_wakeup_set(irq_get_irq_data(irq))) { + pm_wakeup_event(wirq->dev, 0); + + return IRQ_HANDLED; + } + + /* We don't want RPM_ASYNC or RPM_NOWAIT here */ + res = pm_runtime_resume(wirq->dev); + if (res < 0) + dev_warn(wirq->dev, + "wake IRQ with no resume: %i\n", res); + + return IRQ_HANDLED; +} + +static int __dev_pm_set_dedicated_wake_irq(struct device *dev, int irq, unsigned int flag) +{ + struct wake_irq *wirq; + int err; + + if (irq < 0) + return -EINVAL; + + wirq = kzalloc_obj(*wirq); + if (!wirq) + return -ENOMEM; + + wirq->name = kasprintf(GFP_KERNEL, "%s:wakeup", dev_name(dev)); + if (!wirq->name) { + err = -ENOMEM; + goto err_free; + } + + wirq->dev = dev; + wirq->irq = irq; + + /* Prevent deferred spurious wakeirqs with disable_irq_nosync() */ + irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY); + + /* + * Consumer device may need to power up and restore state + * so we use a threaded irq. + */ + err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq, + IRQF_ONESHOT | IRQF_NO_AUTOEN, + wirq->name, wirq); + if (err) + goto err_free_name; + + err = dev_pm_attach_wake_irq(dev, wirq); + if (err) + goto err_free_irq; + + wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED | flag; + + return err; + +err_free_irq: + free_irq(irq, wirq); +err_free_name: + kfree(wirq->name); +err_free: + kfree(wirq); + + return err; +} + +/** + * dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt + * @dev: Device entry + * @irq: Device wake-up interrupt + * + * Unless your hardware has separate wake-up interrupts in addition + * to the device IO interrupts, you don't need this. + * + * Sets up a threaded interrupt handler for a device that has + * a dedicated wake-up interrupt in addition to the device IO + * interrupt. + */ +int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) +{ + return __dev_pm_set_dedicated_wake_irq(dev, irq, 0); +} +EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq); + +/** + * dev_pm_set_dedicated_wake_irq_reverse - Request a dedicated wake-up interrupt + * with reverse enable ordering + * @dev: Device entry + * @irq: Device wake-up interrupt + * + * Unless your hardware has separate wake-up interrupts in addition + * to the device IO interrupts, you don't need this. + * + * Sets up a threaded interrupt handler for a device that has a dedicated + * wake-up interrupt in addition to the device IO interrupt. It sets + * the status of WAKE_IRQ_DEDICATED_REVERSE to tell rpm_suspend() + * to enable dedicated wake-up interrupt after running the runtime suspend + * callback for @dev. + */ +int dev_pm_set_dedicated_wake_irq_reverse(struct device *dev, int irq) +{ + return __dev_pm_set_dedicated_wake_irq(dev, irq, WAKE_IRQ_DEDICATED_REVERSE); +} +EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq_reverse); + +/** + * dev_pm_enable_wake_irq_check - Checks and enables wake-up interrupt + * @dev: Device + * @can_change_status: Can change wake-up interrupt status + * + * Enables wakeirq conditionally. We need to enable wake-up interrupt + * lazily on the first rpm_suspend(). This is needed as the consumer device + * starts in RPM_SUSPENDED state, and the first pm_runtime_get() would + * otherwise try to disable already disabled wakeirq. The wake-up interrupt + * starts disabled with IRQ_NOAUTOEN set. + * + * Should be called from rpm_suspend(), rpm_resume(), + * pm_runtime_force_suspend() or pm_runtime_force_resume(). + * Caller must hold &dev->power.lock or disable runtime PM to change + * wirq->status. + */ +void dev_pm_enable_wake_irq_check(struct device *dev, + bool can_change_status) +{ + struct wake_irq *wirq = dev->power.wakeirq; + + if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK)) + return; + + if (likely(wirq->status & WAKE_IRQ_DEDICATED_MANAGED)) { + goto enable; + } else if (can_change_status) { + wirq->status |= WAKE_IRQ_DEDICATED_MANAGED; + goto enable; + } + + return; + +enable: + if (!can_change_status || !(wirq->status & WAKE_IRQ_DEDICATED_REVERSE)) { + enable_irq(wirq->irq); + wirq->status |= WAKE_IRQ_DEDICATED_ENABLED; + } +} + +/** + * dev_pm_disable_wake_irq_check - Checks and disables wake-up interrupt + * @dev: Device + * @cond_disable: if set, also check WAKE_IRQ_DEDICATED_REVERSE + * + * Disables wake-up interrupt conditionally based on status. + * Should be called from rpm_suspend(), rpm_resume(), + * pm_runtime_force_suspend() or pm_runtime_force_resume(). + */ +void dev_pm_disable_wake_irq_check(struct device *dev, bool cond_disable) +{ + struct wake_irq *wirq = dev->power.wakeirq; + + if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK)) + return; + + if (cond_disable && (wirq->status & WAKE_IRQ_DEDICATED_REVERSE)) + return; + + if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED) { + wirq->status &= ~WAKE_IRQ_DEDICATED_ENABLED; + disable_irq_nosync(wirq->irq); + } +} + +/** + * dev_pm_enable_wake_irq_complete - enable wake IRQ not enabled before + * @dev: Device using the wake IRQ + * + * Enable wake IRQ conditionally based on status, mainly used if want to + * enable wake IRQ after running ->runtime_suspend() which depends on + * WAKE_IRQ_DEDICATED_REVERSE. + * + * Should be called from rpm_suspend() or pm_runtime_force_suspend(). + */ +void dev_pm_enable_wake_irq_complete(struct device *dev) +{ + struct wake_irq *wirq = dev->power.wakeirq; + + if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK)) + return; + + if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED && + wirq->status & WAKE_IRQ_DEDICATED_REVERSE) { + enable_irq(wirq->irq); + wirq->status |= WAKE_IRQ_DEDICATED_ENABLED; + } +} + +/** + * dev_pm_arm_wake_irq - Arm device wake-up + * @wirq: Device wake-up interrupt + * + * Sets up the wake-up event conditionally based on the + * device_may_wake(). + */ +void dev_pm_arm_wake_irq(struct wake_irq *wirq) +{ + if (!wirq) + return; + + if (device_may_wakeup(wirq->dev)) { + if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED && + !(wirq->status & WAKE_IRQ_DEDICATED_ENABLED)) + enable_irq(wirq->irq); + + enable_irq_wake(wirq->irq); + } +} + +/** + * dev_pm_disarm_wake_irq - Disarm device wake-up + * @wirq: Device wake-up interrupt + * + * Clears up the wake-up event conditionally based on the + * device_may_wake(). + */ +void dev_pm_disarm_wake_irq(struct wake_irq *wirq) +{ + if (!wirq) + return; + + if (device_may_wakeup(wirq->dev)) { + disable_irq_wake(wirq->irq); + + if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED && + !(wirq->status & WAKE_IRQ_DEDICATED_ENABLED)) + disable_irq_nosync(wirq->irq); + } +} diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c new file mode 100644 index 000000000..80b497de2 --- /dev/null +++ b/drivers/base/power/wakeup.c @@ -0,0 +1,1245 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/wakeup.c - System wakeup events framework + * + * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + */ +#define pr_fmt(fmt) "PM: " fmt + +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/sched/signal.h> +#include <linux/capability.h> +#include <linux/export.h> +#include <linux/suspend.h> +#include <linux/seq_file.h> +#include <linux/debugfs.h> +#include <linux/pm_wakeirq.h> +#include <trace/events/power.h> + +#include "power.h" + +#define list_for_each_entry_rcu_locked(pos, head, member) \ + list_for_each_entry_rcu(pos, head, member, \ + srcu_read_lock_held(&wakeup_srcu)) +/* + * If set, the suspend/hibernate code will abort transitions to a sleep state + * if wakeup events are registered during or immediately before the transition. + */ +bool events_check_enabled __read_mostly; + +/* First wakeup IRQ seen by the kernel in the last cycle. */ +static unsigned int wakeup_irq[2] __read_mostly; +static DEFINE_RAW_SPINLOCK(wakeup_irq_lock); + +/* If greater than 0 and the system is suspending, terminate the suspend. */ +static atomic_t pm_abort_suspend __read_mostly; + +/* + * Combined counters of registered wakeup events and wakeup events in progress. + * They need to be modified together atomically, so it's better to use one + * atomic variable to hold them both. + */ +static atomic_t combined_event_count = ATOMIC_INIT(0); + +#define IN_PROGRESS_BITS (sizeof(int) * 4) +#define MAX_IN_PROGRESS ((1 << IN_PROGRESS_BITS) - 1) + +static void split_counters(unsigned int *cnt, unsigned int *inpr) +{ + unsigned int comb = atomic_read(&combined_event_count); + + *cnt = (comb >> IN_PROGRESS_BITS); + *inpr = comb & MAX_IN_PROGRESS; +} + +/* A preserved old value of the events counter. */ +static unsigned int saved_count; + +static DEFINE_RAW_SPINLOCK(events_lock); + +static void pm_wakeup_timer_fn(struct timer_list *t); + +static LIST_HEAD(wakeup_sources); + +static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue); + +DEFINE_STATIC_SRCU(wakeup_srcu); + +static struct wakeup_source deleted_ws = { + .name = "deleted", + .lock = __SPIN_LOCK_UNLOCKED(deleted_ws.lock), +}; + +static DEFINE_IDA(wakeup_ida); + +/** + * wakeup_source_create - Create a struct wakeup_source object. + * @name: Name of the new wakeup source. + */ +static struct wakeup_source *wakeup_source_create(const char *name) +{ + struct wakeup_source *ws; + const char *ws_name; + int id; + + ws = kzalloc_obj(*ws); + if (!ws) + goto err_ws; + + ws_name = kstrdup_const(name, GFP_KERNEL); + if (!ws_name) + goto err_name; + ws->name = ws_name; + + id = ida_alloc(&wakeup_ida, GFP_KERNEL); + if (id < 0) + goto err_id; + ws->id = id; + + return ws; + +err_id: + kfree_const(ws->name); +err_name: + kfree(ws); +err_ws: + return NULL; +} + +/* + * Record wakeup_source statistics being deleted into a dummy wakeup_source. + */ +static void wakeup_source_record(struct wakeup_source *ws) +{ + unsigned long flags; + + spin_lock_irqsave(&deleted_ws.lock, flags); + + if (ws->event_count) { + deleted_ws.total_time = + ktime_add(deleted_ws.total_time, ws->total_time); + deleted_ws.prevent_sleep_time = + ktime_add(deleted_ws.prevent_sleep_time, + ws->prevent_sleep_time); + deleted_ws.max_time = + ktime_compare(deleted_ws.max_time, ws->max_time) > 0 ? + deleted_ws.max_time : ws->max_time; + deleted_ws.event_count += ws->event_count; + deleted_ws.active_count += ws->active_count; + deleted_ws.relax_count += ws->relax_count; + deleted_ws.expire_count += ws->expire_count; + deleted_ws.wakeup_count += ws->wakeup_count; + } + + spin_unlock_irqrestore(&deleted_ws.lock, flags); +} + +static void wakeup_source_free(struct wakeup_source *ws) +{ + ida_free(&wakeup_ida, ws->id); + kfree_const(ws->name); + kfree(ws); +} + +/** + * wakeup_source_destroy - Destroy a struct wakeup_source object. + * @ws: Wakeup source to destroy. + * + * Use only for wakeup source objects created with wakeup_source_create(). + */ +static void wakeup_source_destroy(struct wakeup_source *ws) +{ + if (!ws) + return; + + __pm_relax(ws); + wakeup_source_record(ws); + wakeup_source_free(ws); +} + +/** + * wakeup_source_add - Add given object to the list of wakeup sources. + * @ws: Wakeup source object to add to the list. + */ +static void wakeup_source_add(struct wakeup_source *ws) +{ + unsigned long flags; + + if (WARN_ON(!ws)) + return; + + spin_lock_init(&ws->lock); + timer_setup(&ws->timer, pm_wakeup_timer_fn, 0); + ws->active = false; + + raw_spin_lock_irqsave(&events_lock, flags); + list_add_rcu(&ws->entry, &wakeup_sources); + raw_spin_unlock_irqrestore(&events_lock, flags); +} + +/** + * wakeup_source_remove - Remove given object from the wakeup sources list. + * @ws: Wakeup source object to remove from the list. + */ +static void wakeup_source_remove(struct wakeup_source *ws) +{ + unsigned long flags; + + if (WARN_ON(!ws)) + return; + + /* + * After shutting down the timer, wakeup_source_activate() will warn if + * the given wakeup source is passed to it. + */ + timer_shutdown_sync(&ws->timer); + + raw_spin_lock_irqsave(&events_lock, flags); + list_del_rcu(&ws->entry); + raw_spin_unlock_irqrestore(&events_lock, flags); + synchronize_srcu(&wakeup_srcu); +} + +/** + * wakeup_source_register - Create wakeup source and add it to the list. + * @dev: Device this wakeup source is associated with (or NULL if virtual). + * @name: Name of the wakeup source to register. + */ +struct wakeup_source *wakeup_source_register(struct device *dev, + const char *name) +{ + struct wakeup_source *ws; + int ret; + + ws = wakeup_source_create(name); + if (ws) { + if (!dev || device_is_registered(dev)) { + ret = wakeup_source_sysfs_add(dev, ws); + if (ret) { + wakeup_source_free(ws); + return NULL; + } + } + wakeup_source_add(ws); + } + return ws; +} +EXPORT_SYMBOL_GPL(wakeup_source_register); + +/** + * wakeup_source_unregister - Remove wakeup source from the list and remove it. + * @ws: Wakeup source object to unregister. + */ +void wakeup_source_unregister(struct wakeup_source *ws) +{ + if (ws) { + wakeup_source_remove(ws); + if (ws->dev) + wakeup_source_sysfs_remove(ws); + + wakeup_source_destroy(ws); + } +} +EXPORT_SYMBOL_GPL(wakeup_source_unregister); + +/** + * wakeup_sources_read_lock - Lock wakeup source list for read. + * + * Returns an index of srcu lock for struct wakeup_srcu. + * This index must be passed to the matching wakeup_sources_read_unlock(). + */ +int wakeup_sources_read_lock(void) +{ + return srcu_read_lock(&wakeup_srcu); +} +EXPORT_SYMBOL_GPL(wakeup_sources_read_lock); + +/** + * wakeup_sources_read_unlock - Unlock wakeup source list. + * @idx: return value from corresponding wakeup_sources_read_lock() + */ +void wakeup_sources_read_unlock(int idx) +{ + srcu_read_unlock(&wakeup_srcu, idx); +} +EXPORT_SYMBOL_GPL(wakeup_sources_read_unlock); + +/** + * wakeup_sources_walk_start - Begin a walk on wakeup source list + * + * Returns first object of the list of wakeup sources. + * + * Note that to be safe, wakeup sources list needs to be locked by calling + * wakeup_source_read_lock() for this. + */ +struct wakeup_source *wakeup_sources_walk_start(void) +{ + return list_first_or_null_rcu(&wakeup_sources, struct wakeup_source, entry); +} +EXPORT_SYMBOL_GPL(wakeup_sources_walk_start); + +/** + * wakeup_sources_walk_next - Get next wakeup source from the list + * @ws: Previous wakeup source object + * + * Note that to be safe, wakeup sources list needs to be locked by calling + * wakeup_source_read_lock() for this. + */ +struct wakeup_source *wakeup_sources_walk_next(struct wakeup_source *ws) +{ + struct list_head *ws_head = &wakeup_sources; + + return list_next_or_null_rcu(ws_head, &ws->entry, + struct wakeup_source, entry); +} +EXPORT_SYMBOL_GPL(wakeup_sources_walk_next); + +/** + * device_wakeup_attach - Attach a wakeup source object to a device object. + * @dev: Device to handle. + * @ws: Wakeup source object to attach to @dev. + * + * This causes @dev to be treated as a wakeup device. + */ +static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws) +{ + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + spin_unlock_irq(&dev->power.lock); + return -EEXIST; + } + dev->power.wakeup = ws; + if (dev->power.wakeirq) + device_wakeup_attach_irq(dev, dev->power.wakeirq); + spin_unlock_irq(&dev->power.lock); + return 0; +} + +/** + * device_wakeup_enable - Enable given device to be a wakeup source. + * @dev: Device to handle. + * + * Create a wakeup source object, register it and attach it to @dev. + */ +int device_wakeup_enable(struct device *dev) +{ + struct wakeup_source *ws; + int ret; + + if (!dev || !dev->power.can_wakeup) + return -EINVAL; + + if (pm_sleep_transition_in_progress()) + dev_dbg(dev, "Suspicious %s() during system transition!\n", __func__); + + ws = wakeup_source_register(dev, dev_name(dev)); + if (!ws) + return -ENOMEM; + + ret = device_wakeup_attach(dev, ws); + if (ret) + wakeup_source_unregister(ws); + + return ret; +} +EXPORT_SYMBOL_GPL(device_wakeup_enable); + +/** + * device_wakeup_attach_irq - Attach a wakeirq to a wakeup source + * @dev: Device to handle + * @wakeirq: Device specific wakeirq entry + * + * Attach a device wakeirq to the wakeup source so the device + * wake IRQ can be configured automatically for suspend and + * resume. + * + * Call under the device's power.lock lock. + */ +void device_wakeup_attach_irq(struct device *dev, + struct wake_irq *wakeirq) +{ + struct wakeup_source *ws; + + ws = dev->power.wakeup; + if (!ws) + return; + + if (ws->wakeirq) + dev_err(dev, "Leftover wakeup IRQ found, overriding\n"); + + ws->wakeirq = wakeirq; +} + +/** + * device_wakeup_detach_irq - Detach a wakeirq from a wakeup source + * @dev: Device to handle + * + * Removes a device wakeirq from the wakeup source. + * + * Call under the device's power.lock lock. + */ +void device_wakeup_detach_irq(struct device *dev) +{ + struct wakeup_source *ws; + + ws = dev->power.wakeup; + if (ws) + ws->wakeirq = NULL; +} + +/** + * device_wakeup_arm_wake_irqs - + * + * Iterates over the list of device wakeirqs to arm them. + */ +void device_wakeup_arm_wake_irqs(void) +{ + struct wakeup_source *ws; + int srcuidx; + + srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) + dev_pm_arm_wake_irq(ws->wakeirq); + srcu_read_unlock(&wakeup_srcu, srcuidx); +} + +/** + * device_wakeup_disarm_wake_irqs - + * + * Iterates over the list of device wakeirqs to disarm them. + */ +void device_wakeup_disarm_wake_irqs(void) +{ + struct wakeup_source *ws; + int srcuidx; + + srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) + dev_pm_disarm_wake_irq(ws->wakeirq); + srcu_read_unlock(&wakeup_srcu, srcuidx); +} + +/** + * device_wakeup_detach - Detach a device's wakeup source object from it. + * @dev: Device to detach the wakeup source object from. + * + * After it returns, @dev will not be treated as a wakeup device any more. + */ +static struct wakeup_source *device_wakeup_detach(struct device *dev) +{ + struct wakeup_source *ws; + + spin_lock_irq(&dev->power.lock); + ws = dev->power.wakeup; + dev->power.wakeup = NULL; + spin_unlock_irq(&dev->power.lock); + return ws; +} + +/** + * device_wakeup_disable - Do not regard a device as a wakeup source any more. + * @dev: Device to handle. + * + * Detach the @dev's wakeup source object from it, unregister this wakeup source + * object and destroy it. + */ +void device_wakeup_disable(struct device *dev) +{ + struct wakeup_source *ws; + + if (!dev || !dev->power.can_wakeup) + return; + + ws = device_wakeup_detach(dev); + wakeup_source_unregister(ws); +} +EXPORT_SYMBOL_GPL(device_wakeup_disable); + +/** + * device_set_wakeup_capable - Set/reset device wakeup capability flag. + * @dev: Device to handle. + * @capable: Whether or not @dev is capable of waking up the system from sleep. + * + * If @capable is set, set the @dev's power.can_wakeup flag and add its + * wakeup-related attributes to sysfs. Otherwise, unset the @dev's + * power.can_wakeup flag and remove its wakeup-related attributes from sysfs. + * + * This function may sleep and it can't be called from any context where + * sleeping is not allowed. + */ +void device_set_wakeup_capable(struct device *dev, bool capable) +{ + if (!!dev->power.can_wakeup == !!capable) + return; + + dev->power.can_wakeup = capable; + if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { + if (capable) { + int ret = wakeup_sysfs_add(dev); + + if (ret) + dev_info(dev, "Wakeup sysfs attributes not added\n"); + } else { + wakeup_sysfs_remove(dev); + } + } +} +EXPORT_SYMBOL_GPL(device_set_wakeup_capable); + +/** + * device_set_wakeup_enable - Enable or disable a device to wake up the system. + * @dev: Device to handle. + * @enable: enable/disable flag + */ +int device_set_wakeup_enable(struct device *dev, bool enable) +{ + if (enable) + return device_wakeup_enable(dev); + + device_wakeup_disable(dev); + return 0; +} +EXPORT_SYMBOL_GPL(device_set_wakeup_enable); + +/** + * wakeup_source_not_usable - validate the given wakeup source. + * @ws: Wakeup source to be validated. + */ +static bool wakeup_source_not_usable(struct wakeup_source *ws) +{ + /* + * Use the timer struct to check if the given wakeup source has been + * initialized by wakeup_source_add() and it is not going away. + */ + return ws->timer.function != pm_wakeup_timer_fn; +} + +/* + * The functions below use the observation that each wakeup event starts a + * period in which the system should not be suspended. The moment this period + * will end depends on how the wakeup event is going to be processed after being + * detected and all of the possible cases can be divided into two distinct + * groups. + * + * First, a wakeup event may be detected by the same functional unit that will + * carry out the entire processing of it and possibly will pass it to user space + * for further processing. In that case the functional unit that has detected + * the event may later "close" the "no suspend" period associated with it + * directly as soon as it has been dealt with. The pair of pm_stay_awake() and + * pm_relax(), balanced with each other, is supposed to be used in such + * situations. + * + * Second, a wakeup event may be detected by one functional unit and processed + * by another one. In that case the unit that has detected it cannot really + * "close" the "no suspend" period associated with it, unless it knows in + * advance what's going to happen to the event during processing. This + * knowledge, however, may not be available to it, so it can simply specify time + * to wait before the system can be suspended and pass it as the second + * argument of pm_wakeup_event(). + * + * It is valid to call pm_relax() after pm_wakeup_event(), in which case the + * "no suspend" period will be ended either by the pm_relax(), or by the timer + * function executed when the timer expires, whichever comes first. + */ + +/** + * wakeup_source_activate - Mark given wakeup source as active. + * @ws: Wakeup source to handle. + * + * Update the @ws' statistics and, if @ws has just been activated, notify the PM + * core of the event by incrementing the counter of the wakeup events being + * processed. + */ +static void wakeup_source_activate(struct wakeup_source *ws) +{ + unsigned int cec; + + if (WARN_ONCE(wakeup_source_not_usable(ws), "unusable wakeup source\n")) + return; + + ws->active = true; + ws->active_count++; + ws->last_time = ktime_get(); + if (ws->autosleep_enabled) + ws->start_prevent_time = ws->last_time; + + /* Increment the counter of events in progress. */ + cec = atomic_inc_return(&combined_event_count); + + trace_wakeup_source_activate(ws->name, cec); +} + +/** + * wakeup_source_report_event - Report wakeup event using the given source. + * @ws: Wakeup source to report the event for. + * @hard: If set, abort suspends in progress and wake up from suspend-to-idle. + */ +static void wakeup_source_report_event(struct wakeup_source *ws, bool hard) +{ + ws->event_count++; + /* This is racy, but the counter is approximate anyway. */ + if (events_check_enabled) + ws->wakeup_count++; + + if (!ws->active) + wakeup_source_activate(ws); + + if (hard) + pm_system_wakeup(); +} + +/** + * __pm_stay_awake - Notify the PM core of a wakeup event. + * @ws: Wakeup source object associated with the source of the event. + * + * It is safe to call this function from interrupt context. + */ +void __pm_stay_awake(struct wakeup_source *ws) +{ + unsigned long flags; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + + wakeup_source_report_event(ws, false); + timer_delete(&ws->timer); + ws->timer_expires = 0; + + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(__pm_stay_awake); + +/** + * pm_stay_awake - Notify the PM core that a wakeup event is being processed. + * @dev: Device the wakeup event is related to. + * + * Notify the PM core of a wakeup event (signaled by @dev) by calling + * __pm_stay_awake for the @dev's wakeup source object. + * + * Call this function after detecting of a wakeup event if pm_relax() is going + * to be called directly after processing the event (and possibly passing it to + * user space for further processing). + */ +void pm_stay_awake(struct device *dev) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + __pm_stay_awake(dev->power.wakeup); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_stay_awake); + +#ifdef CONFIG_PM_AUTOSLEEP +static void update_prevent_sleep_time(struct wakeup_source *ws, ktime_t now) +{ + ktime_t delta = ktime_sub(now, ws->start_prevent_time); + ws->prevent_sleep_time = ktime_add(ws->prevent_sleep_time, delta); +} +#else +static inline void update_prevent_sleep_time(struct wakeup_source *ws, + ktime_t now) {} +#endif + +/** + * wakeup_source_deactivate - Mark given wakeup source as inactive. + * @ws: Wakeup source to handle. + * + * Update the @ws' statistics and notify the PM core that the wakeup source has + * become inactive by decrementing the counter of wakeup events being processed + * and incrementing the counter of registered wakeup events. + */ +static void wakeup_source_deactivate(struct wakeup_source *ws) +{ + unsigned int cnt, inpr, cec; + ktime_t duration; + ktime_t now; + + ws->relax_count++; + /* + * __pm_relax() may be called directly or from a timer function. + * If it is called directly right after the timer function has been + * started, but before the timer function calls __pm_relax(), it is + * possible that __pm_stay_awake() will be called in the meantime and + * will set ws->active. Then, ws->active may be cleared immediately + * by the __pm_relax() called from the timer function, but in such a + * case ws->relax_count will be different from ws->active_count. + */ + if (ws->relax_count != ws->active_count) { + ws->relax_count--; + return; + } + + ws->active = false; + + now = ktime_get(); + duration = ktime_sub(now, ws->last_time); + ws->total_time = ktime_add(ws->total_time, duration); + if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time)) + ws->max_time = duration; + + ws->last_time = now; + timer_delete(&ws->timer); + ws->timer_expires = 0; + + if (ws->autosleep_enabled) + update_prevent_sleep_time(ws, now); + + /* + * Increment the counter of registered wakeup events and decrement the + * counter of wakeup events in progress simultaneously. + */ + cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count); + trace_wakeup_source_deactivate(ws->name, cec); + + split_counters(&cnt, &inpr); + if (!inpr && waitqueue_active(&wakeup_count_wait_queue)) + wake_up(&wakeup_count_wait_queue); +} + +/** + * __pm_relax - Notify the PM core that processing of a wakeup event has ended. + * @ws: Wakeup source object associated with the source of the event. + * + * Call this function for wakeup events whose processing started with calling + * __pm_stay_awake(). + * + * It is safe to call it from interrupt context. + */ +void __pm_relax(struct wakeup_source *ws) +{ + unsigned long flags; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + if (ws->active) + wakeup_source_deactivate(ws); + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(__pm_relax); + +/** + * pm_relax - Notify the PM core that processing of a wakeup event has ended. + * @dev: Device that signaled the event. + * + * Execute __pm_relax() for the @dev's wakeup source object. + */ +void pm_relax(struct device *dev) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + __pm_relax(dev->power.wakeup); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_relax); + +/** + * pm_wakeup_timer_fn - Delayed finalization of a wakeup event. + * @t: timer list + * + * Call wakeup_source_deactivate() for the wakeup source whose address is stored + * in @data if it is currently active and its timer has not been canceled and + * the expiration time of the timer is not in future. + */ +static void pm_wakeup_timer_fn(struct timer_list *t) +{ + struct wakeup_source *ws = timer_container_of(ws, t, timer); + unsigned long flags; + + spin_lock_irqsave(&ws->lock, flags); + + if (ws->active && ws->timer_expires + && time_after_eq(jiffies, ws->timer_expires)) { + wakeup_source_deactivate(ws); + ws->expire_count++; + } + + spin_unlock_irqrestore(&ws->lock, flags); +} + +/** + * pm_wakeup_ws_event - Notify the PM core of a wakeup event. + * @ws: Wakeup source object associated with the event source. + * @msec: Anticipated event processing time (in milliseconds). + * @hard: If set, abort suspends in progress and wake up from suspend-to-idle. + * + * Notify the PM core of a wakeup event whose source is @ws that will take + * approximately @msec milliseconds to be processed by the kernel. If @ws is + * not active, activate it. If @msec is nonzero, set up the @ws' timer to + * execute pm_wakeup_timer_fn() in future. + * + * It is safe to call this function from interrupt context. + */ +void pm_wakeup_ws_event(struct wakeup_source *ws, unsigned int msec, bool hard) +{ + unsigned long flags; + unsigned long expires; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + + wakeup_source_report_event(ws, hard); + + if (!msec) { + wakeup_source_deactivate(ws); + goto unlock; + } + + expires = jiffies + msecs_to_jiffies(msec); + if (!expires) + expires = 1; + + if (!ws->timer_expires || time_after(expires, ws->timer_expires)) { + mod_timer(&ws->timer, expires); + ws->timer_expires = expires; + } + + unlock: + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(pm_wakeup_ws_event); + +/** + * pm_wakeup_dev_event - Notify the PM core of a wakeup event. + * @dev: Device the wakeup event is related to. + * @msec: Anticipated event processing time (in milliseconds). + * @hard: If set, abort suspends in progress and wake up from suspend-to-idle. + * + * Call pm_wakeup_ws_event() for the @dev's wakeup source object. + */ +void pm_wakeup_dev_event(struct device *dev, unsigned int msec, bool hard) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + pm_wakeup_ws_event(dev->power.wakeup, msec, hard); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_wakeup_dev_event); + +void pm_print_active_wakeup_sources(void) +{ + struct wakeup_source *ws; + int srcuidx, active = 0; + struct wakeup_source *last_activity_ws = NULL; + + srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) { + if (ws->active) { + pm_pr_dbg("active wakeup source: %s\n", ws->name); + active = 1; + } else if (!active && + (!last_activity_ws || + ktime_to_ns(ws->last_time) > + ktime_to_ns(last_activity_ws->last_time))) { + last_activity_ws = ws; + } + } + + if (!active && last_activity_ws) + pm_pr_dbg("last active wakeup source: %s\n", + last_activity_ws->name); + srcu_read_unlock(&wakeup_srcu, srcuidx); +} +EXPORT_SYMBOL_GPL(pm_print_active_wakeup_sources); + +/** + * pm_wakeup_pending - Check if power transition in progress should be aborted. + * + * Compare the current number of registered wakeup events with its preserved + * value from the past and return true if new wakeup events have been registered + * since the old value was stored. Also return true if the current number of + * wakeup events being processed is different from zero. + */ +bool pm_wakeup_pending(void) +{ + unsigned long flags; + bool ret = false; + + raw_spin_lock_irqsave(&events_lock, flags); + if (events_check_enabled) { + unsigned int cnt, inpr; + + split_counters(&cnt, &inpr); + ret = (cnt != saved_count || inpr > 0); + events_check_enabled = !ret; + } + raw_spin_unlock_irqrestore(&events_lock, flags); + + if (ret) { + pm_pr_dbg("Wakeup pending, aborting suspend\n"); + pm_print_active_wakeup_sources(); + } + + return ret || atomic_read(&pm_abort_suspend) > 0; +} +EXPORT_SYMBOL_GPL(pm_wakeup_pending); + +void pm_system_wakeup(void) +{ + atomic_inc(&pm_abort_suspend); + s2idle_wake(); +} +EXPORT_SYMBOL_GPL(pm_system_wakeup); + +void pm_system_cancel_wakeup(void) +{ + atomic_dec_if_positive(&pm_abort_suspend); +} + +void pm_wakeup_clear(unsigned int irq_number) +{ + raw_spin_lock_irq(&wakeup_irq_lock); + + if (irq_number && wakeup_irq[0] == irq_number) + wakeup_irq[0] = wakeup_irq[1]; + else + wakeup_irq[0] = 0; + + wakeup_irq[1] = 0; + + raw_spin_unlock_irq(&wakeup_irq_lock); + + if (!irq_number) + atomic_set(&pm_abort_suspend, 0); +} + +void pm_system_irq_wakeup(unsigned int irq_number) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&wakeup_irq_lock, flags); + + if (wakeup_irq[0] == 0) + wakeup_irq[0] = irq_number; + else if (wakeup_irq[1] == 0) + wakeup_irq[1] = irq_number; + else + irq_number = 0; + + pm_pr_dbg("Triggering wakeup from IRQ %d\n", irq_number); + + raw_spin_unlock_irqrestore(&wakeup_irq_lock, flags); + + if (irq_number) + pm_system_wakeup(); +} + +unsigned int pm_wakeup_irq(void) +{ + return wakeup_irq[0]; +} + +/** + * pm_get_wakeup_count - Read the number of registered wakeup events. + * @count: Address to store the value at. + * @block: Whether or not to block. + * + * Store the number of registered wakeup events at the address in @count. If + * @block is set, block until the current number of wakeup events being + * processed is zero. + * + * Return 'false' if the current number of wakeup events being processed is + * nonzero. Otherwise return 'true'. + */ +bool pm_get_wakeup_count(unsigned int *count, bool block) +{ + unsigned int cnt, inpr; + + if (block) { + DEFINE_WAIT(wait); + + for (;;) { + prepare_to_wait(&wakeup_count_wait_queue, &wait, + TASK_INTERRUPTIBLE); + split_counters(&cnt, &inpr); + if (inpr == 0 || signal_pending(current)) + break; + pm_print_active_wakeup_sources(); + schedule(); + } + finish_wait(&wakeup_count_wait_queue, &wait); + } + + split_counters(&cnt, &inpr); + *count = cnt; + return !inpr; +} + +/** + * pm_save_wakeup_count - Save the current number of registered wakeup events. + * @count: Value to compare with the current number of registered wakeup events. + * + * If @count is equal to the current number of registered wakeup events and the + * current number of wakeup events being processed is zero, store @count as the + * old number of registered wakeup events for pm_check_wakeup_events(), enable + * wakeup events detection and return 'true'. Otherwise disable wakeup events + * detection and return 'false'. + */ +bool pm_save_wakeup_count(unsigned int count) +{ + unsigned int cnt, inpr; + unsigned long flags; + + events_check_enabled = false; + raw_spin_lock_irqsave(&events_lock, flags); + split_counters(&cnt, &inpr); + if (cnt == count && inpr == 0) { + saved_count = count; + events_check_enabled = true; + } + raw_spin_unlock_irqrestore(&events_lock, flags); + return events_check_enabled; +} + +#ifdef CONFIG_PM_AUTOSLEEP +/** + * pm_wakep_autosleep_enabled - Modify autosleep_enabled for all wakeup sources. + * @set: Whether to set or to clear the autosleep_enabled flags. + */ +void pm_wakep_autosleep_enabled(bool set) +{ + struct wakeup_source *ws; + ktime_t now = ktime_get(); + int srcuidx; + + srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) { + spin_lock_irq(&ws->lock); + if (ws->autosleep_enabled != set) { + ws->autosleep_enabled = set; + if (ws->active) { + if (set) + ws->start_prevent_time = now; + else + update_prevent_sleep_time(ws, now); + } + } + spin_unlock_irq(&ws->lock); + } + srcu_read_unlock(&wakeup_srcu, srcuidx); +} +#endif /* CONFIG_PM_AUTOSLEEP */ + +/** + * print_wakeup_source_stats - Print wakeup source statistics information. + * @m: seq_file to print the statistics into. + * @ws: Wakeup source object to print the statistics for. + */ +static int print_wakeup_source_stats(struct seq_file *m, + struct wakeup_source *ws) +{ + unsigned long flags; + ktime_t total_time; + ktime_t max_time; + unsigned long active_count; + ktime_t active_time; + ktime_t prevent_sleep_time; + + spin_lock_irqsave(&ws->lock, flags); + + total_time = ws->total_time; + max_time = ws->max_time; + prevent_sleep_time = ws->prevent_sleep_time; + active_count = ws->active_count; + if (ws->active) { + ktime_t now = ktime_get(); + + active_time = ktime_sub(now, ws->last_time); + total_time = ktime_add(total_time, active_time); + if (active_time > max_time) + max_time = active_time; + + if (ws->autosleep_enabled) + prevent_sleep_time = ktime_add(prevent_sleep_time, + ktime_sub(now, ws->start_prevent_time)); + } else { + active_time = 0; + } + + seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t%lu\t\t%lld\t\t%lld\t\t%lld\t\t%lld\t\t%lld\n", + ws->name, active_count, ws->event_count, + ws->wakeup_count, ws->expire_count, + ktime_to_ms(active_time), ktime_to_ms(total_time), + ktime_to_ms(max_time), ktime_to_ms(ws->last_time), + ktime_to_ms(prevent_sleep_time)); + + spin_unlock_irqrestore(&ws->lock, flags); + + return 0; +} + +static void *wakeup_sources_stats_seq_start(struct seq_file *m, + loff_t *pos) +{ + struct wakeup_source *ws; + loff_t n = *pos; + int *srcuidx = m->private; + + if (n == 0) { + seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t" + "expire_count\tactive_since\ttotal_time\tmax_time\t" + "last_change\tprevent_suspend_time\n"); + } + + *srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) { + if (n-- <= 0) + return ws; + } + + return NULL; +} + +static void *wakeup_sources_stats_seq_next(struct seq_file *m, + void *v, loff_t *pos) +{ + struct wakeup_source *ws = v; + struct wakeup_source *next_ws = NULL; + + ++(*pos); + + list_for_each_entry_continue_rcu(ws, &wakeup_sources, entry) { + next_ws = ws; + break; + } + + if (!next_ws) + print_wakeup_source_stats(m, &deleted_ws); + + return next_ws; +} + +static void wakeup_sources_stats_seq_stop(struct seq_file *m, void *v) +{ + int *srcuidx = m->private; + + srcu_read_unlock(&wakeup_srcu, *srcuidx); +} + +/** + * wakeup_sources_stats_seq_show - Print wakeup sources statistics information. + * @m: seq_file to print the statistics into. + * @v: wakeup_source of each iteration + */ +static int wakeup_sources_stats_seq_show(struct seq_file *m, void *v) +{ + struct wakeup_source *ws = v; + + print_wakeup_source_stats(m, ws); + + return 0; +} + +static const struct seq_operations wakeup_sources_stats_seq_ops = { + .start = wakeup_sources_stats_seq_start, + .next = wakeup_sources_stats_seq_next, + .stop = wakeup_sources_stats_seq_stop, + .show = wakeup_sources_stats_seq_show, +}; + +static int wakeup_sources_stats_open(struct inode *inode, struct file *file) +{ + return seq_open_private(file, &wakeup_sources_stats_seq_ops, sizeof(int)); +} + +static const struct file_operations wakeup_sources_stats_fops = { + .owner = THIS_MODULE, + .open = wakeup_sources_stats_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release_private, +}; + +#ifdef CONFIG_BPF_SYSCALL +#include <linux/btf.h> + +__bpf_kfunc_start_defs(); + +/** + * bpf_wakeup_sources_read_lock - Acquire the SRCU lock for wakeup sources + * + * The underlying SRCU lock returns an integer index. However, the BPF verifier + * requires a pointer (PTR_TO_BTF_ID) to strictly track the state of acquired + * resources using KF_ACQUIRE and KF_RELEASE semantics. We use an opaque + * structure pointer (struct bpf_ws_lock *) to satisfy the verifier while + * safely encoding the integer index within the pointer address itself. + * + * Return: An opaque pointer encoding the SRCU lock index + 1 (to avoid NULL). + */ +__bpf_kfunc struct bpf_ws_lock *bpf_wakeup_sources_read_lock(void) +{ + return (struct bpf_ws_lock *)(long)(wakeup_sources_read_lock() + 1); +} + +/** + * bpf_wakeup_sources_read_unlock - Release the SRCU lock for wakeup sources + * @lock: The opaque pointer returned by bpf_wakeup_sources_read_lock() + * + * The BPF verifier guarantees that @lock is a valid, unreleased pointer from + * the acquire function. We decode the pointer back into the integer SRCU index + * by subtracting 1 and release the lock. + */ +__bpf_kfunc void bpf_wakeup_sources_read_unlock(struct bpf_ws_lock *lock) +{ + wakeup_sources_read_unlock((int)(long)lock - 1); +} + +/** + * bpf_wakeup_sources_get_head - Get the head of the wakeup sources list + * + * Return: The head of the wakeup sources list. + */ +__bpf_kfunc void *bpf_wakeup_sources_get_head(void) +{ + return &wakeup_sources; +} + +__bpf_kfunc_end_defs(); + +BTF_KFUNCS_START(wakeup_source_kfunc_ids) +BTF_ID_FLAGS(func, bpf_wakeup_sources_read_lock, KF_ACQUIRE) +BTF_ID_FLAGS(func, bpf_wakeup_sources_read_unlock, KF_RELEASE) +BTF_ID_FLAGS(func, bpf_wakeup_sources_get_head) +BTF_KFUNCS_END(wakeup_source_kfunc_ids) + +static const struct btf_kfunc_id_set wakeup_source_kfunc_set = { + .set = &wakeup_source_kfunc_ids, +}; + +static void __init wakeup_sources_bpf_init(void) +{ + if (register_btf_kfunc_id_set(BPF_PROG_TYPE_SYSCALL, &wakeup_source_kfunc_set)) + pm_pr_dbg("Wakeup: failed to register BTF kfuncs\n"); +} +#else +static inline void wakeup_sources_bpf_init(void) {} +#endif /* CONFIG_BPF_SYSCALL */ + +static int __init wakeup_sources_init(void) +{ + debugfs_create_file("wakeup_sources", 0444, NULL, NULL, + &wakeup_sources_stats_fops); + wakeup_sources_bpf_init(); + + return 0; +} + +postcore_initcall(wakeup_sources_init); diff --git a/drivers/base/power/wakeup_stats.c b/drivers/base/power/wakeup_stats.c new file mode 100644 index 000000000..308f8bde9 --- /dev/null +++ b/drivers/base/power/wakeup_stats.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Wakeup statistics in sysfs + * + * Copyright (c) 2019 Linux Foundation + * Copyright (c) 2019 Greg Kroah-Hartman <gregkh@linuxfoundation.org> + * Copyright (c) 2019 Google Inc. + */ + +#include <linux/device.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/kdev_t.h> +#include <linux/kernel.h> +#include <linux/kobject.h> +#include <linux/slab.h> +#include <linux/timekeeping.h> + +#include "power.h" + +static struct class *wakeup_class; + +#define wakeup_attr(_name) \ +static ssize_t _name##_show(struct device *dev, \ + struct device_attribute *attr, char *buf) \ +{ \ + struct wakeup_source *ws = dev_get_drvdata(dev); \ + \ + return sysfs_emit(buf, "%lu\n", ws->_name); \ +} \ +static DEVICE_ATTR_RO(_name) + +wakeup_attr(active_count); +wakeup_attr(event_count); +wakeup_attr(wakeup_count); +wakeup_attr(expire_count); +wakeup_attr(relax_count); + +static ssize_t active_time_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct wakeup_source *ws = dev_get_drvdata(dev); + ktime_t active_time = + ws->active ? ktime_sub(ktime_get(), ws->last_time) : 0; + + return sysfs_emit(buf, "%lld\n", ktime_to_ms(active_time)); +} +static DEVICE_ATTR_RO(active_time_ms); + +static ssize_t total_time_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct wakeup_source *ws = dev_get_drvdata(dev); + ktime_t active_time; + ktime_t total_time = ws->total_time; + + if (ws->active) { + active_time = ktime_sub(ktime_get(), ws->last_time); + total_time = ktime_add(total_time, active_time); + } + + return sysfs_emit(buf, "%lld\n", ktime_to_ms(total_time)); +} +static DEVICE_ATTR_RO(total_time_ms); + +static ssize_t max_time_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct wakeup_source *ws = dev_get_drvdata(dev); + ktime_t active_time; + ktime_t max_time = ws->max_time; + + if (ws->active) { + active_time = ktime_sub(ktime_get(), ws->last_time); + if (active_time > max_time) + max_time = active_time; + } + + return sysfs_emit(buf, "%lld\n", ktime_to_ms(max_time)); +} +static DEVICE_ATTR_RO(max_time_ms); + +static ssize_t last_change_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct wakeup_source *ws = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%lld\n", ktime_to_ms(ws->last_time)); +} +static DEVICE_ATTR_RO(last_change_ms); + +static ssize_t name_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct wakeup_source *ws = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%s\n", ws->name); +} +static DEVICE_ATTR_RO(name); + +static ssize_t prevent_suspend_time_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct wakeup_source *ws = dev_get_drvdata(dev); + ktime_t prevent_sleep_time = ws->prevent_sleep_time; + + if (ws->active && ws->autosleep_enabled) { + prevent_sleep_time = ktime_add(prevent_sleep_time, + ktime_sub(ktime_get(), ws->start_prevent_time)); + } + + return sysfs_emit(buf, "%lld\n", ktime_to_ms(prevent_sleep_time)); +} +static DEVICE_ATTR_RO(prevent_suspend_time_ms); + +static struct attribute *wakeup_source_attrs[] = { + &dev_attr_name.attr, + &dev_attr_active_count.attr, + &dev_attr_event_count.attr, + &dev_attr_wakeup_count.attr, + &dev_attr_expire_count.attr, + &dev_attr_relax_count.attr, + &dev_attr_active_time_ms.attr, + &dev_attr_total_time_ms.attr, + &dev_attr_max_time_ms.attr, + &dev_attr_last_change_ms.attr, + &dev_attr_prevent_suspend_time_ms.attr, + NULL, +}; +ATTRIBUTE_GROUPS(wakeup_source); + +static void device_create_release(struct device *dev) +{ + kfree(dev); +} + +static struct device *wakeup_source_device_create(struct device *parent, + struct wakeup_source *ws) +{ + struct device *dev = NULL; + int retval; + + dev = kzalloc_obj(*dev); + if (!dev) { + retval = -ENOMEM; + goto error; + } + + device_initialize(dev); + dev->devt = MKDEV(0, 0); + dev->class = wakeup_class; + dev->parent = parent; + dev->groups = wakeup_source_groups; + dev->release = device_create_release; + dev_set_drvdata(dev, ws); + device_set_pm_not_required(dev); + + retval = dev_set_name(dev, "wakeup%d", ws->id); + if (retval) + goto error; + + retval = device_add(dev); + if (retval) + goto error; + + return dev; + +error: + put_device(dev); + return ERR_PTR(retval); +} + +/** + * wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs. + * @parent: Device given wakeup source is associated with (or NULL if virtual). + * @ws: Wakeup source to be added in sysfs. + */ +int wakeup_source_sysfs_add(struct device *parent, struct wakeup_source *ws) +{ + struct device *dev; + + dev = wakeup_source_device_create(parent, ws); + if (IS_ERR(dev)) + return PTR_ERR(dev); + ws->dev = dev; + + return 0; +} + +/** + * pm_wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs + * for a device if they're missing. + * @parent: Device given wakeup source is associated with + */ +int pm_wakeup_source_sysfs_add(struct device *parent) +{ + if (!parent->power.wakeup || parent->power.wakeup->dev) + return 0; + + return wakeup_source_sysfs_add(parent, parent->power.wakeup); +} + +/** + * wakeup_source_sysfs_remove - Remove wakeup_source attributes from sysfs. + * @ws: Wakeup source to be removed from sysfs. + */ +void wakeup_source_sysfs_remove(struct wakeup_source *ws) +{ + device_unregister(ws->dev); +} + +static int __init wakeup_sources_sysfs_init(void) +{ + wakeup_class = class_create("wakeup"); + + return PTR_ERR_OR_ZERO(wakeup_class); +} +postcore_initcall(wakeup_sources_sysfs_init); |
