From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/leds/led-class.c | 683 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 683 insertions(+) create mode 100644 drivers/leds/led-class.c (limited to 'drivers/leds/led-class.c') diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c new file mode 100644 index 000000000..ba1be15cf --- /dev/null +++ b/drivers/leds/led-class.c @@ -0,0 +1,683 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * LED Class Core + * + * Copyright (C) 2005 John Lenz + * Copyright (C) 2005-2007 Richard Purdie + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "leds.h" + +static DEFINE_MUTEX(leds_lookup_lock); +static LIST_HEAD(leds_lookup_list); + +static ssize_t brightness_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + + /* no lock needed for this */ + led_update_brightness(led_cdev); + + return sprintf(buf, "%u\n", led_cdev->brightness); +} + +static ssize_t brightness_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + unsigned long state; + ssize_t ret; + + mutex_lock(&led_cdev->led_access); + + if (led_sysfs_is_disabled(led_cdev)) { + ret = -EBUSY; + goto unlock; + } + + ret = kstrtoul(buf, 10, &state); + if (ret) + goto unlock; + + if (state == LED_OFF) + led_trigger_remove(led_cdev); + led_set_brightness(led_cdev, state); + flush_work(&led_cdev->set_brightness_work); + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_access); + return ret; +} +static DEVICE_ATTR_RW(brightness); + +static ssize_t max_brightness_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + + return sprintf(buf, "%u\n", led_cdev->max_brightness); +} +static DEVICE_ATTR_RO(max_brightness); + +#ifdef CONFIG_LEDS_TRIGGERS +static BIN_ATTR(trigger, 0644, led_trigger_read, led_trigger_write, 0); +static struct bin_attribute *led_trigger_bin_attrs[] = { + &bin_attr_trigger, + NULL, +}; +static const struct attribute_group led_trigger_group = { + .bin_attrs = led_trigger_bin_attrs, +}; +#endif + +static struct attribute *led_class_attrs[] = { + &dev_attr_brightness.attr, + &dev_attr_max_brightness.attr, + NULL, +}; + +static const struct attribute_group led_group = { + .attrs = led_class_attrs, +}; + +static const struct attribute_group *led_groups[] = { + &led_group, +#ifdef CONFIG_LEDS_TRIGGERS + &led_trigger_group, +#endif + NULL, +}; + +#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED +static ssize_t brightness_hw_changed_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + + if (led_cdev->brightness_hw_changed == -1) + return -ENODATA; + + return sprintf(buf, "%u\n", led_cdev->brightness_hw_changed); +} + +static DEVICE_ATTR_RO(brightness_hw_changed); + +static int led_add_brightness_hw_changed(struct led_classdev *led_cdev) +{ + struct device *dev = led_cdev->dev; + int ret; + + ret = device_create_file(dev, &dev_attr_brightness_hw_changed); + if (ret) { + dev_err(dev, "Error creating brightness_hw_changed\n"); + return ret; + } + + led_cdev->brightness_hw_changed_kn = + sysfs_get_dirent(dev->kobj.sd, "brightness_hw_changed"); + if (!led_cdev->brightness_hw_changed_kn) { + dev_err(dev, "Error getting brightness_hw_changed kn\n"); + device_remove_file(dev, &dev_attr_brightness_hw_changed); + return -ENXIO; + } + + return 0; +} + +static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev) +{ + sysfs_put(led_cdev->brightness_hw_changed_kn); + device_remove_file(led_cdev->dev, &dev_attr_brightness_hw_changed); +} + +void led_classdev_notify_brightness_hw_changed(struct led_classdev *led_cdev, unsigned int brightness) +{ + if (WARN_ON(!led_cdev->brightness_hw_changed_kn)) + return; + + led_cdev->brightness_hw_changed = brightness; + sysfs_notify_dirent(led_cdev->brightness_hw_changed_kn); +} +EXPORT_SYMBOL_GPL(led_classdev_notify_brightness_hw_changed); +#else +static int led_add_brightness_hw_changed(struct led_classdev *led_cdev) +{ + return 0; +} +static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev) +{ +} +#endif + +/** + * led_classdev_suspend - suspend an led_classdev. + * @led_cdev: the led_classdev to suspend. + */ +void led_classdev_suspend(struct led_classdev *led_cdev) +{ + led_cdev->flags |= LED_SUSPENDED; + led_set_brightness_nopm(led_cdev, 0); + flush_work(&led_cdev->set_brightness_work); +} +EXPORT_SYMBOL_GPL(led_classdev_suspend); + +/** + * led_classdev_resume - resume an led_classdev. + * @led_cdev: the led_classdev to resume. + */ +void led_classdev_resume(struct led_classdev *led_cdev) +{ + led_set_brightness_nopm(led_cdev, led_cdev->brightness); + + if (led_cdev->flash_resume) + led_cdev->flash_resume(led_cdev); + + led_cdev->flags &= ~LED_SUSPENDED; +} +EXPORT_SYMBOL_GPL(led_classdev_resume); + +#ifdef CONFIG_PM_SLEEP +static int led_suspend(struct device *dev) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + + if (led_cdev->flags & LED_CORE_SUSPENDRESUME) + led_classdev_suspend(led_cdev); + + return 0; +} + +static int led_resume(struct device *dev) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + + if (led_cdev->flags & LED_CORE_SUSPENDRESUME) + led_classdev_resume(led_cdev); + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume); + +static struct led_classdev *led_module_get(struct device *led_dev) +{ + struct led_classdev *led_cdev; + + if (!led_dev) + return ERR_PTR(-EPROBE_DEFER); + + led_cdev = dev_get_drvdata(led_dev); + + if (!try_module_get(led_cdev->dev->parent->driver->owner)) { + put_device(led_cdev->dev); + return ERR_PTR(-ENODEV); + } + + return led_cdev; +} + +static const struct class leds_class = { + .name = "leds", + .dev_groups = led_groups, + .pm = &leds_class_dev_pm_ops, +}; + +/** + * of_led_get() - request a LED device via the LED framework + * @np: device node to get the LED device from + * @index: the index of the LED + * + * Returns the LED device parsed from the phandle specified in the "leds" + * property of a device tree node or a negative error-code on failure. + */ +struct led_classdev *of_led_get(struct device_node *np, int index) +{ + struct device *led_dev; + struct device_node *led_node; + + led_node = of_parse_phandle(np, "leds", index); + if (!led_node) + return ERR_PTR(-ENOENT); + + led_dev = class_find_device_by_of_node(&leds_class, led_node); + of_node_put(led_node); + put_device(led_dev); + + return led_module_get(led_dev); +} +EXPORT_SYMBOL_GPL(of_led_get); + +/** + * led_put() - release a LED device + * @led_cdev: LED device + */ +void led_put(struct led_classdev *led_cdev) +{ + module_put(led_cdev->dev->parent->driver->owner); + put_device(led_cdev->dev); +} +EXPORT_SYMBOL_GPL(led_put); + +static void devm_led_release(struct device *dev, void *res) +{ + struct led_classdev **p = res; + + led_put(*p); +} + +static struct led_classdev *__devm_led_get(struct device *dev, struct led_classdev *led) +{ + struct led_classdev **dr; + + dr = devres_alloc(devm_led_release, sizeof(struct led_classdev *), GFP_KERNEL); + if (!dr) { + led_put(led); + return ERR_PTR(-ENOMEM); + } + + *dr = led; + devres_add(dev, dr); + + return led; +} + +/** + * devm_of_led_get - Resource-managed request of a LED device + * @dev: LED consumer + * @index: index of the LED to obtain in the consumer + * + * The device node of the device is parse to find the request LED device. + * The LED device returned from this function is automatically released + * on driver detach. + * + * @return a pointer to a LED device or ERR_PTR(errno) on failure. + */ +struct led_classdev *__must_check devm_of_led_get(struct device *dev, + int index) +{ + struct led_classdev *led; + + if (!dev) + return ERR_PTR(-EINVAL); + + led = of_led_get(dev->of_node, index); + if (IS_ERR(led)) + return led; + + return __devm_led_get(dev, led); +} +EXPORT_SYMBOL_GPL(devm_of_led_get); + +/** + * led_get() - request a LED device via the LED framework + * @dev: device for which to get the LED device + * @con_id: name of the LED from the device's point of view + * + * @return a pointer to a LED device or ERR_PTR(errno) on failure. + */ +struct led_classdev *led_get(struct device *dev, char *con_id) +{ + struct led_lookup_data *lookup; + const char *provider = NULL; + struct device *led_dev; + + mutex_lock(&leds_lookup_lock); + list_for_each_entry(lookup, &leds_lookup_list, list) { + if (!strcmp(lookup->dev_id, dev_name(dev)) && + !strcmp(lookup->con_id, con_id)) { + provider = kstrdup_const(lookup->provider, GFP_KERNEL); + break; + } + } + mutex_unlock(&leds_lookup_lock); + + if (!provider) + return ERR_PTR(-ENOENT); + + led_dev = class_find_device_by_name(&leds_class, provider); + kfree_const(provider); + + return led_module_get(led_dev); +} +EXPORT_SYMBOL_GPL(led_get); + +/** + * devm_led_get() - request a LED device via the LED framework + * @dev: device for which to get the LED device + * @con_id: name of the LED from the device's point of view + * + * The LED device returned from this function is automatically released + * on driver detach. + * + * @return a pointer to a LED device or ERR_PTR(errno) on failure. + */ +struct led_classdev *devm_led_get(struct device *dev, char *con_id) +{ + struct led_classdev *led; + + led = led_get(dev, con_id); + if (IS_ERR(led)) + return led; + + return __devm_led_get(dev, led); +} +EXPORT_SYMBOL_GPL(devm_led_get); + +/** + * led_add_lookup() - Add a LED lookup table entry + * @led_lookup: the lookup table entry to add + * + * Add a LED lookup table entry. On systems without devicetree the lookup table + * is used by led_get() to find LEDs. + */ +void led_add_lookup(struct led_lookup_data *led_lookup) +{ + mutex_lock(&leds_lookup_lock); + list_add_tail(&led_lookup->list, &leds_lookup_list); + mutex_unlock(&leds_lookup_lock); +} +EXPORT_SYMBOL_GPL(led_add_lookup); + +/** + * led_remove_lookup() - Remove a LED lookup table entry + * @led_lookup: the lookup table entry to remove + */ +void led_remove_lookup(struct led_lookup_data *led_lookup) +{ + mutex_lock(&leds_lookup_lock); + list_del(&led_lookup->list); + mutex_unlock(&leds_lookup_lock); +} +EXPORT_SYMBOL_GPL(led_remove_lookup); + +/** + * devm_of_led_get_optional - Resource-managed request of an optional LED device + * @dev: LED consumer + * @index: index of the LED to obtain in the consumer + * + * The device node of the device is parsed to find the requested LED device. + * The LED device returned from this function is automatically released + * on driver detach. + * + * @return a pointer to a LED device, ERR_PTR(errno) on failure and NULL if the + * led was not found. + */ +struct led_classdev *__must_check devm_of_led_get_optional(struct device *dev, + int index) +{ + struct led_classdev *led; + + led = devm_of_led_get(dev, index); + if (IS_ERR(led) && PTR_ERR(led) == -ENOENT) + return NULL; + + return led; +} +EXPORT_SYMBOL_GPL(devm_of_led_get_optional); + +static int led_classdev_next_name(const char *init_name, char *name, + size_t len) +{ + unsigned int i = 0; + int ret = 0; + struct device *dev; + + strscpy(name, init_name, len); + + while ((ret < len) && + (dev = class_find_device_by_name(&leds_class, name))) { + put_device(dev); + ret = snprintf(name, len, "%s_%u", init_name, ++i); + } + + if (ret >= len) + return -ENOMEM; + + return i; +} + +/** + * led_classdev_register_ext - register a new object of led_classdev class + * with init data. + * + * @parent: parent of LED device + * @led_cdev: the led_classdev structure for this device. + * @init_data: LED class device initialization data + */ +int led_classdev_register_ext(struct device *parent, + struct led_classdev *led_cdev, + struct led_init_data *init_data) +{ + char composed_name[LED_MAX_NAME_SIZE]; + char final_name[LED_MAX_NAME_SIZE]; + const char *proposed_name = composed_name; + int ret; + + if (init_data) { + if (init_data->devname_mandatory && !init_data->devicename) { + dev_err(parent, "Mandatory device name is missing"); + return -EINVAL; + } + ret = led_compose_name(parent, init_data, composed_name); + if (ret < 0) + return ret; + + if (init_data->fwnode) { + fwnode_property_read_string(init_data->fwnode, + "linux,default-trigger", + &led_cdev->default_trigger); + + if (fwnode_property_present(init_data->fwnode, + "retain-state-shutdown")) + led_cdev->flags |= LED_RETAIN_AT_SHUTDOWN; + + fwnode_property_read_u32(init_data->fwnode, + "max-brightness", + &led_cdev->max_brightness); + + if (fwnode_property_present(init_data->fwnode, "color")) + fwnode_property_read_u32(init_data->fwnode, "color", + &led_cdev->color); + } + } else { + proposed_name = led_cdev->name; + } + + ret = led_classdev_next_name(proposed_name, final_name, sizeof(final_name)); + if (ret < 0) + return ret; + + if (led_cdev->color >= LED_COLOR_ID_MAX) + dev_warn(parent, "LED %s color identifier out of range\n", final_name); + + mutex_init(&led_cdev->led_access); + mutex_lock(&led_cdev->led_access); + led_cdev->dev = device_create_with_groups(&leds_class, parent, 0, + led_cdev, led_cdev->groups, "%s", final_name); + if (IS_ERR(led_cdev->dev)) { + mutex_unlock(&led_cdev->led_access); + return PTR_ERR(led_cdev->dev); + } + if (init_data && init_data->fwnode) + device_set_node(led_cdev->dev, init_data->fwnode); + + if (ret) + dev_warn(parent, "Led %s renamed to %s due to name collision", + proposed_name, dev_name(led_cdev->dev)); + + if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) { + ret = led_add_brightness_hw_changed(led_cdev); + if (ret) { + device_unregister(led_cdev->dev); + led_cdev->dev = NULL; + mutex_unlock(&led_cdev->led_access); + return ret; + } + } + + led_cdev->work_flags = 0; +#ifdef CONFIG_LEDS_TRIGGERS + init_rwsem(&led_cdev->trigger_lock); +#endif +#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED + led_cdev->brightness_hw_changed = -1; +#endif + /* add to the list of leds */ + down_write(&leds_list_lock); + list_add_tail(&led_cdev->node, &leds_list); + up_write(&leds_list_lock); + + if (!led_cdev->max_brightness) + led_cdev->max_brightness = LED_FULL; + + led_update_brightness(led_cdev); + + led_init_core(led_cdev); + +#ifdef CONFIG_LEDS_TRIGGERS + led_trigger_set_default(led_cdev); +#endif + + mutex_unlock(&led_cdev->led_access); + + dev_dbg(parent, "Registered led device: %s\n", + led_cdev->name); + + return 0; +} +EXPORT_SYMBOL_GPL(led_classdev_register_ext); + +/** + * led_classdev_unregister - unregisters a object of led_properties class. + * @led_cdev: the led device to unregister + * + * Unregisters a previously registered via led_classdev_register object. + */ +void led_classdev_unregister(struct led_classdev *led_cdev) +{ + if (IS_ERR_OR_NULL(led_cdev->dev)) + return; + +#ifdef CONFIG_LEDS_TRIGGERS + down_write(&led_cdev->trigger_lock); + if (led_cdev->trigger) + led_trigger_set(led_cdev, NULL); + up_write(&led_cdev->trigger_lock); +#endif + + led_cdev->flags |= LED_UNREGISTERING; + + /* Stop blinking */ + led_stop_software_blink(led_cdev); + + if (!(led_cdev->flags & LED_RETAIN_AT_SHUTDOWN)) + led_set_brightness(led_cdev, LED_OFF); + + flush_work(&led_cdev->set_brightness_work); + + if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) + led_remove_brightness_hw_changed(led_cdev); + + device_unregister(led_cdev->dev); + + down_write(&leds_list_lock); + list_del(&led_cdev->node); + up_write(&leds_list_lock); + + mutex_destroy(&led_cdev->led_access); +} +EXPORT_SYMBOL_GPL(led_classdev_unregister); + +static void devm_led_classdev_release(struct device *dev, void *res) +{ + led_classdev_unregister(*(struct led_classdev **)res); +} + +/** + * devm_led_classdev_register_ext - resource managed led_classdev_register_ext() + * + * @parent: parent of LED device + * @led_cdev: the led_classdev structure for this device. + * @init_data: LED class device initialization data + */ +int devm_led_classdev_register_ext(struct device *parent, + struct led_classdev *led_cdev, + struct led_init_data *init_data) +{ + struct led_classdev **dr; + int rc; + + dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL); + if (!dr) + return -ENOMEM; + + rc = led_classdev_register_ext(parent, led_cdev, init_data); + if (rc) { + devres_free(dr); + return rc; + } + + *dr = led_cdev; + devres_add(parent, dr); + + return 0; +} +EXPORT_SYMBOL_GPL(devm_led_classdev_register_ext); + +static int devm_led_classdev_match(struct device *dev, void *res, void *data) +{ + struct led_classdev **p = res; + + if (WARN_ON(!p || !*p)) + return 0; + + return *p == data; +} + +/** + * devm_led_classdev_unregister() - resource managed led_classdev_unregister() + * @dev: The device to unregister. + * @led_cdev: the led_classdev structure for this device. + */ +void devm_led_classdev_unregister(struct device *dev, + struct led_classdev *led_cdev) +{ + WARN_ON(devres_release(dev, + devm_led_classdev_release, + devm_led_classdev_match, led_cdev)); +} +EXPORT_SYMBOL_GPL(devm_led_classdev_unregister); + +static int __init leds_init(void) +{ + return class_register(&leds_class); +} + +static void __exit leds_exit(void) +{ + class_unregister(&leds_class); +} + +subsys_initcall(leds_init); +module_exit(leds_exit); + +MODULE_AUTHOR("John Lenz, Richard Purdie"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("LED Class Interface"); -- cgit v1.2.3