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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/power/reset/reboot-mode.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/power/reset/reboot-mode.c')
| -rw-r--r-- | drivers/power/reset/reboot-mode.c | 357 |
1 files changed, 357 insertions, 0 deletions
diff --git a/drivers/power/reset/reboot-mode.c b/drivers/power/reset/reboot-mode.c new file mode 100644 index 000000000..af00c00ec --- /dev/null +++ b/drivers/power/reset/reboot-mode.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/property.h> +#include <linux/reboot.h> +#include <linux/reboot-mode.h> +#include <linux/slab.h> +#include <linux/string.h> + +#define PREFIX "mode-" + +struct mode_info { + const char *mode; + u32 magic; + struct list_head list; +}; + +struct reboot_mode_sysfs_data { + struct device *reboot_mode_device; + struct list_head head; +}; + +static inline void reboot_mode_release_list(struct reboot_mode_sysfs_data *priv) +{ + struct mode_info *info; + struct mode_info *next; + + list_for_each_entry_safe(info, next, &priv->head, list) { + list_del(&info->list); + kfree_const(info->mode); + kfree(info); + } +} + +static ssize_t reboot_modes_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct reboot_mode_sysfs_data *priv; + struct mode_info *sysfs_info; + ssize_t size = 0; + + priv = dev_get_drvdata(dev); + if (!priv) + return -ENODATA; + + list_for_each_entry(sysfs_info, &priv->head, list) + size += sysfs_emit_at(buf, size, "%s ", sysfs_info->mode); + + if (!size) + return -ENODATA; + + return size + sysfs_emit_at(buf, size - 1, "\n"); +} +static DEVICE_ATTR_RO(reboot_modes); + +static struct attribute *reboot_mode_attrs[] = { + &dev_attr_reboot_modes.attr, + NULL, +}; +ATTRIBUTE_GROUPS(reboot_mode); + +static const struct class reboot_mode_class = { + .name = "reboot-mode", + .dev_groups = reboot_mode_groups, +}; + +static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot, + const char *cmd) +{ + const char *normal = "normal"; + struct mode_info *info; + char cmd_[110]; + + if (!cmd) + cmd = normal; + + list_for_each_entry(info, &reboot->head, list) + if (!strcmp(info->mode, cmd)) + return info->magic; + + /* try to match again, replacing characters impossible in DT */ + if (strscpy(cmd_, cmd, sizeof(cmd_)) == -E2BIG) + return 0; + + strreplace(cmd_, ' ', '-'); + strreplace(cmd_, ',', '-'); + strreplace(cmd_, '/', '-'); + + list_for_each_entry(info, &reboot->head, list) + if (!strcmp(info->mode, cmd_)) + return info->magic; + + return 0; +} + +static int reboot_mode_notify(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + struct reboot_mode_driver *reboot; + unsigned int magic; + + reboot = container_of(this, struct reboot_mode_driver, reboot_notifier); + magic = get_reboot_mode_magic(reboot, cmd); + if (magic) + reboot->write(reboot, magic); + + return NOTIFY_DONE; +} + +static int reboot_mode_create_device(struct reboot_mode_driver *reboot) +{ + struct reboot_mode_sysfs_data *priv; + struct mode_info *sysfs_info; + struct mode_info *info; + int ret; + + priv = kzalloc_obj(*priv, GFP_KERNEL); + if (!priv) + return -ENOMEM; + + INIT_LIST_HEAD(&priv->head); + + list_for_each_entry(info, &reboot->head, list) { + sysfs_info = kzalloc_obj(*sysfs_info, GFP_KERNEL); + if (!sysfs_info) { + ret = -ENOMEM; + goto error; + } + + sysfs_info->mode = kstrdup_const(info->mode, GFP_KERNEL); + if (!sysfs_info->mode) { + kfree(sysfs_info); + ret = -ENOMEM; + goto error; + } + + list_add_tail(&sysfs_info->list, &priv->head); + } + + priv->reboot_mode_device = device_create(&reboot_mode_class, NULL, 0, + (void *)priv, "%s", + reboot->dev->driver->name); + if (IS_ERR(priv->reboot_mode_device)) { + ret = PTR_ERR(priv->reboot_mode_device); + goto error; + } + + return 0; + +error: + reboot_mode_release_list(priv); + kfree(priv); + return ret; +} + +/** + * reboot_mode_register - register a reboot mode driver + * @reboot: reboot mode driver + * + * Returns: 0 on success or a negative error code on failure. + */ +int reboot_mode_register(struct reboot_mode_driver *reboot) +{ + struct mode_info *info = NULL; + struct property *prop; + struct device_node *np = reboot->dev->of_node; + size_t len = strlen(PREFIX); + u32 magic; + int ret; + + INIT_LIST_HEAD(&reboot->head); + + for_each_property_of_node(np, prop) { + if (strncmp(prop->name, PREFIX, len)) + continue; + + if (device_property_read_u32(reboot->dev, prop->name, &magic)) { + dev_dbg(reboot->dev, "reboot mode %s without magic number\n", + prop->name); + continue; + } + + info = kzalloc_obj(*info, GFP_KERNEL); + if (!info) { + ret = -ENOMEM; + goto error; + } + + info->magic = magic; + info->mode = kstrdup_const(prop->name + len, GFP_KERNEL); + if (!info->mode) { + ret = -ENOMEM; + goto error; + } else if (info->mode[0] == '\0') { + kfree_const(info->mode); + ret = -EINVAL; + dev_err(reboot->dev, "invalid mode name(%s): too short!\n", + prop->name); + goto error; + } + + list_add_tail(&info->list, &reboot->head); + info = NULL; + } + + reboot->reboot_notifier.notifier_call = reboot_mode_notify; + register_reboot_notifier(&reboot->reboot_notifier); + + ret = reboot_mode_create_device(reboot); + if (ret) + goto error; + + return 0; + +error: + kfree(info); + reboot_mode_unregister(reboot); + return ret; +} +EXPORT_SYMBOL_GPL(reboot_mode_register); + +static int reboot_mode_match_by_name(struct device *dev, const void *data) +{ + const char *name = data; + + if (!dev || !data) + return 0; + + return dev_name(dev) && strcmp(dev_name(dev), name) == 0; +} + +static inline void reboot_mode_unregister_device(struct reboot_mode_driver *reboot) +{ + struct reboot_mode_sysfs_data *priv; + struct device *reboot_mode_device; + + reboot_mode_device = class_find_device(&reboot_mode_class, NULL, reboot->dev->driver->name, + reboot_mode_match_by_name); + + if (!reboot_mode_device) + return; + + priv = dev_get_drvdata(reboot_mode_device); + device_unregister(reboot_mode_device); + + if (!priv) + return; + + reboot_mode_release_list(priv); + kfree(priv); +} + +/** + * reboot_mode_unregister - unregister a reboot mode driver + * @reboot: reboot mode driver + */ +int reboot_mode_unregister(struct reboot_mode_driver *reboot) +{ + struct mode_info *info; + struct mode_info *next; + + unregister_reboot_notifier(&reboot->reboot_notifier); + reboot_mode_unregister_device(reboot); + + list_for_each_entry_safe(info, next, &reboot->head, list) { + list_del(&info->list); + kfree_const(info->mode); + kfree(info); + } + + return 0; +} +EXPORT_SYMBOL_GPL(reboot_mode_unregister); + +static void devm_reboot_mode_release(struct device *dev, void *res) +{ + reboot_mode_unregister(*(struct reboot_mode_driver **)res); +} + +/** + * devm_reboot_mode_register() - resource managed reboot_mode_register() + * @dev: device to associate this resource with + * @reboot: reboot mode driver + * + * Returns: 0 on success or a negative error code on failure. + */ +int devm_reboot_mode_register(struct device *dev, + struct reboot_mode_driver *reboot) +{ + struct reboot_mode_driver **dr; + int rc; + + dr = devres_alloc(devm_reboot_mode_release, sizeof(*dr), GFP_KERNEL); + if (!dr) + return -ENOMEM; + + rc = reboot_mode_register(reboot); + if (rc) { + devres_free(dr); + return rc; + } + + *dr = reboot; + devres_add(dev, dr); + + return 0; +} +EXPORT_SYMBOL_GPL(devm_reboot_mode_register); + +static int devm_reboot_mode_match(struct device *dev, void *res, void *data) +{ + struct reboot_mode_driver **p = res; + + if (WARN_ON(!p || !*p)) + return 0; + + return *p == data; +} + +/** + * devm_reboot_mode_unregister() - resource managed reboot_mode_unregister() + * @dev: device to associate this resource with + * @reboot: reboot mode driver + */ +void devm_reboot_mode_unregister(struct device *dev, + struct reboot_mode_driver *reboot) +{ + WARN_ON(devres_release(dev, + devm_reboot_mode_release, + devm_reboot_mode_match, reboot)); +} +EXPORT_SYMBOL_GPL(devm_reboot_mode_unregister); + +static int __init reboot_mode_init(void) +{ + return class_register(&reboot_mode_class); +} + +static void __exit reboot_mode_exit(void) +{ + class_unregister(&reboot_mode_class); +} + +subsys_initcall(reboot_mode_init); +module_exit(reboot_mode_exit); + +MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com>"); +MODULE_DESCRIPTION("System reboot mode core library"); +MODULE_LICENSE("GPL v2"); |
