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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /drivers/clk/clkdev.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'drivers/clk/clkdev.c')
| -rw-r--r-- | drivers/clk/clkdev.c | 418 |
1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c new file mode 100644 index 000000000..abaa0f9e0 --- /dev/null +++ b/drivers/clk/clkdev.c @@ -0,0 +1,418 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * drivers/clk/clkdev.c + * + * Copyright (C) 2008 Russell King. + * + * Helper for the clk API to assist looking up a struct clk. + */ +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/list.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/string.h> +#include <linux/mutex.h> +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/of.h> + +#include "clk.h" + +static LIST_HEAD(clocks); +static DEFINE_MUTEX(clocks_mutex); + +/* + * Find the correct struct clk for the device and connection ID. + * We do slightly fuzzy matching here: + * An entry with a NULL ID is assumed to be a wildcard. + * If an entry has a device ID, it must match + * If an entry has a connection ID, it must match + * Then we take the most specific entry - with the following + * order of precedence: dev+con > dev only > con only. + */ +static struct clk_lookup *clk_find(const char *dev_id, const char *con_id) +{ + struct clk_lookup *p, *cl = NULL; + int match, best_found = 0, best_possible = 0; + + if (dev_id) + best_possible += 2; + if (con_id) + best_possible += 1; + + lockdep_assert_held(&clocks_mutex); + + list_for_each_entry(p, &clocks, node) { + match = 0; + if (p->dev_id) { + if (!dev_id || strcmp(p->dev_id, dev_id)) + continue; + match += 2; + } + if (p->con_id) { + if (!con_id || strcmp(p->con_id, con_id)) + continue; + match += 1; + } + + if (match > best_found) { + cl = p; + if (match != best_possible) + best_found = match; + else + break; + } + } + return cl; +} + +struct clk_hw *clk_find_hw(const char *dev_id, const char *con_id) +{ + struct clk_lookup *cl; + struct clk_hw *hw = ERR_PTR(-ENOENT); + + mutex_lock(&clocks_mutex); + cl = clk_find(dev_id, con_id); + if (cl) + hw = cl->clk_hw; + mutex_unlock(&clocks_mutex); + + return hw; +} + +static struct clk *__clk_get_sys(struct device *dev, const char *dev_id, + const char *con_id) +{ + struct clk_hw *hw = clk_find_hw(dev_id, con_id); + + return clk_hw_create_clk(dev, hw, dev_id, con_id); +} + +struct clk *clk_get_sys(const char *dev_id, const char *con_id) +{ + return __clk_get_sys(NULL, dev_id, con_id); +} +EXPORT_SYMBOL(clk_get_sys); + +struct clk *clk_get(struct device *dev, const char *con_id) +{ + const char *dev_id = dev ? dev_name(dev) : NULL; + struct clk_hw *hw; + + if (dev && dev->of_node) { + hw = of_clk_get_hw(dev->of_node, 0, con_id); + if (!IS_ERR(hw) || PTR_ERR(hw) == -EPROBE_DEFER) + return clk_hw_create_clk(dev, hw, dev_id, con_id); + } + + return __clk_get_sys(dev, dev_id, con_id); +} +EXPORT_SYMBOL(clk_get); + +void clk_put(struct clk *clk) +{ + __clk_put(clk); +} +EXPORT_SYMBOL(clk_put); + +static void __clkdev_add(struct clk_lookup *cl) +{ + mutex_lock(&clocks_mutex); + list_add_tail(&cl->node, &clocks); + mutex_unlock(&clocks_mutex); +} + +void clkdev_add(struct clk_lookup *cl) +{ + if (!cl->clk_hw) + cl->clk_hw = __clk_get_hw(cl->clk); + __clkdev_add(cl); +} +EXPORT_SYMBOL(clkdev_add); + +void clkdev_add_table(struct clk_lookup *cl, size_t num) +{ + mutex_lock(&clocks_mutex); + while (num--) { + cl->clk_hw = __clk_get_hw(cl->clk); + list_add_tail(&cl->node, &clocks); + cl++; + } + mutex_unlock(&clocks_mutex); +} + +#define MAX_DEV_ID 24 +#define MAX_CON_ID 16 + +struct clk_lookup_alloc { + struct clk_lookup cl; + char dev_id[MAX_DEV_ID]; + char con_id[MAX_CON_ID]; +}; + +static __printf(3, 0) struct clk_lookup * __ref +vclkdev_alloc(struct clk_hw *hw, const char *con_id, const char *dev_fmt, + va_list ap) +{ + struct clk_lookup_alloc *cla; + struct va_format vaf; + const char *failure; + va_list ap_copy; + size_t max_size; + ssize_t res; + + cla = kzalloc_obj(*cla); + if (!cla) + return NULL; + + va_copy(ap_copy, ap); + + cla->cl.clk_hw = hw; + if (con_id) { + res = strscpy(cla->con_id, con_id, sizeof(cla->con_id)); + if (res < 0) { + max_size = sizeof(cla->con_id); + failure = "connection"; + goto fail; + } + cla->cl.con_id = cla->con_id; + } + + if (dev_fmt) { + res = vsnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap); + if (res >= sizeof(cla->dev_id)) { + max_size = sizeof(cla->dev_id); + failure = "device"; + goto fail; + } + cla->cl.dev_id = cla->dev_id; + } + + va_end(ap_copy); + + return &cla->cl; + +fail: + if (dev_fmt) + vaf.fmt = dev_fmt; + else + vaf.fmt = "null-device"; + vaf.va = &ap_copy; + pr_err("%pV:%s: %s ID is greater than %zu\n", + &vaf, con_id, failure, max_size); + va_end(ap_copy); + + /* + * Don't fail in this case, but as the entry won't ever match just + * fill it with something that also won't match. + */ + strscpy(cla->con_id, "bad", sizeof(cla->con_id)); + strscpy(cla->dev_id, "bad", sizeof(cla->dev_id)); + + return &cla->cl; +} + +static __printf(3, 0) struct clk_lookup * +vclkdev_create(struct clk_hw *hw, const char *con_id, const char *dev_fmt, + va_list ap) +{ + struct clk_lookup *cl; + + cl = vclkdev_alloc(hw, con_id, dev_fmt, ap); + if (cl) + __clkdev_add(cl); + + return cl; +} + +/** + * clkdev_create - allocate and add a clkdev lookup structure + * @clk: struct clk to associate with all clk_lookups + * @con_id: connection ID string on device + * @dev_fmt: format string describing device name + * + * Returns a clk_lookup structure, which can be later unregistered and + * freed. + */ +struct clk_lookup *clkdev_create(struct clk *clk, const char *con_id, + const char *dev_fmt, ...) +{ + struct clk_lookup *cl; + va_list ap; + + va_start(ap, dev_fmt); + cl = vclkdev_create(__clk_get_hw(clk), con_id, dev_fmt, ap); + va_end(ap); + + return cl; +} +EXPORT_SYMBOL_GPL(clkdev_create); + +/** + * clkdev_hw_create - allocate and add a clkdev lookup structure + * @hw: struct clk_hw to associate with all clk_lookups + * @con_id: connection ID string on device + * @dev_fmt: format string describing device name + * + * Returns a clk_lookup structure, which can be later unregistered and + * freed. + */ +struct clk_lookup *clkdev_hw_create(struct clk_hw *hw, const char *con_id, + const char *dev_fmt, ...) +{ + struct clk_lookup *cl; + va_list ap; + + va_start(ap, dev_fmt); + cl = vclkdev_create(hw, con_id, dev_fmt, ap); + va_end(ap); + + return cl; +} +EXPORT_SYMBOL_GPL(clkdev_hw_create); + +int clk_add_alias(const char *alias, const char *alias_dev_name, + const char *con_id, struct device *dev) +{ + struct clk *r = clk_get(dev, con_id); + struct clk_lookup *l; + + if (IS_ERR(r)) + return PTR_ERR(r); + + l = clkdev_create(r, alias, alias_dev_name ? "%s" : NULL, + alias_dev_name); + clk_put(r); + + return l ? 0 : -ENODEV; +} +EXPORT_SYMBOL(clk_add_alias); + +/* + * clkdev_drop - remove a clock dynamically allocated + */ +void clkdev_drop(struct clk_lookup *cl) +{ + mutex_lock(&clocks_mutex); + list_del(&cl->node); + mutex_unlock(&clocks_mutex); + kfree(cl); +} +EXPORT_SYMBOL(clkdev_drop); + +static __printf(3, 4) struct clk_lookup * +__clk_register_clkdev(struct clk_hw *hw, const char *con_id, const char *dev_id, ...) +{ + struct clk_lookup *cl; + va_list ap; + + va_start(ap, dev_id); + cl = vclkdev_create(hw, con_id, dev_id, ap); + va_end(ap); + + return cl; +} + +static int do_clk_register_clkdev(struct clk_hw *hw, + struct clk_lookup **cl, const char *con_id, const char *dev_id) +{ + if (IS_ERR(hw)) + return PTR_ERR(hw); + /* + * Since dev_id can be NULL, and NULL is handled specially, we must + * pass it as either a NULL format string, or with "%s". + */ + if (dev_id) + *cl = __clk_register_clkdev(hw, con_id, "%s", dev_id); + else + *cl = __clk_register_clkdev(hw, con_id, NULL); + + return *cl ? 0 : -ENOMEM; +} + +/** + * clk_register_clkdev - register one clock lookup for a struct clk + * @clk: struct clk to associate with all clk_lookups + * @con_id: connection ID string on device + * @dev_id: string describing device name + * + * con_id or dev_id may be NULL as a wildcard, just as in the rest of + * clkdev. + * + * To make things easier for mass registration, we detect error clks + * from a previous clk_register() call, and return the error code for + * those. This is to permit this function to be called immediately + * after clk_register(). + */ +int clk_register_clkdev(struct clk *clk, const char *con_id, + const char *dev_id) +{ + struct clk_lookup *cl; + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + return do_clk_register_clkdev(__clk_get_hw(clk), &cl, con_id, + dev_id); +} +EXPORT_SYMBOL(clk_register_clkdev); + +/** + * clk_hw_register_clkdev - register one clock lookup for a struct clk_hw + * @hw: struct clk_hw to associate with all clk_lookups + * @con_id: connection ID string on device + * @dev_id: format string describing device name + * + * con_id or dev_id may be NULL as a wildcard, just as in the rest of + * clkdev. + * + * To make things easier for mass registration, we detect error clk_hws + * from a previous clk_hw_register_*() call, and return the error code for + * those. This is to permit this function to be called immediately + * after clk_hw_register_*(). + */ +int clk_hw_register_clkdev(struct clk_hw *hw, const char *con_id, + const char *dev_id) +{ + struct clk_lookup *cl; + + return do_clk_register_clkdev(hw, &cl, con_id, dev_id); +} +EXPORT_SYMBOL(clk_hw_register_clkdev); + +static void devm_clkdev_release(void *res) +{ + clkdev_drop(res); +} + +/** + * devm_clk_hw_register_clkdev - managed clk lookup registration for clk_hw + * @dev: device this lookup is bound + * @hw: struct clk_hw to associate with all clk_lookups + * @con_id: connection ID string on device + * @dev_id: format string describing device name + * + * con_id or dev_id may be NULL as a wildcard, just as in the rest of + * clkdev. + * + * To make things easier for mass registration, we detect error clk_hws + * from a previous clk_hw_register_*() call, and return the error code for + * those. This is to permit this function to be called immediately + * after clk_hw_register_*(). + */ +int devm_clk_hw_register_clkdev(struct device *dev, struct clk_hw *hw, + const char *con_id, const char *dev_id) +{ + struct clk_lookup *cl; + int rval; + + rval = do_clk_register_clkdev(hw, &cl, con_id, dev_id); + if (rval) + return rval; + + return devm_add_action_or_reset(dev, devm_clkdev_release, cl); +} +EXPORT_SYMBOL(devm_clk_hw_register_clkdev); |
