[linux-block.git] / drivers / leds / led-class.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * LED Class Core
 *
 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
 * Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
 */

#include <linux/ctype.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/leds.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <uapi/linux/uleds.h>
#include <linux/of.h>
#include "leds.h"

static struct class *leds_class;

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);

/**
 * 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 led_classdev *led_cdev;
	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);

	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))
		return ERR_PTR(-ENODEV);

	return led_cdev;
}
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);
}
EXPORT_SYMBOL_GPL(led_put);

static void devm_led_release(struct device *dev, void *res)
{
	struct led_classdev **p = res;

	led_put(*p);
}

/**
 * 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;
	struct led_classdev **dr;

	if (!dev)
		return ERR_PTR(-EINVAL);

	led = of_led_get(dev->of_node, index);
	if (IS_ERR(led))
		return led;

	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;
}
EXPORT_SYMBOL_GPL(devm_of_led_get);

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;

	strlcpy(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;
		}
	} else {
		proposed_name = led_cdev->name;
	}

	ret = led_classdev_next_name(proposed_name, final_name, sizeof(final_name));
	if (ret < 0)
		return ret;

	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)
{
	leds_class = class_create(THIS_MODULE, "leds");
	if (IS_ERR(leds_class))
		return PTR_ERR(leds_class);
	leds_class->pm = &leds_class_dev_pm_ops;
	leds_class->dev_groups = led_groups;
	return 0;
}

static void __exit leds_exit(void)
{
	class_destroy(leds_class);
}

subsys_initcall(leds_init);
module_exit(leds_exit);

MODULE_AUTHOR("John Lenz, Richard Purdie");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LED Class Interface");
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
c72a1d60 RP	2	/*
	3	* LED Class Core
	4	*
	5	* Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
f8a7c6fe	6	* Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
c72a1d60 RP	7	*/
c72a1d60 RP	8
04713306 JA	9	#include <linux/ctype.h>
	10	#include <linux/device.h>
	11	#include <linux/err.h>
c72a1d60	12	#include <linux/init.h>
04713306 JA	13	#include <linux/kernel.h>
04713306 JA	14	#include <linux/leds.h>
c72a1d60	15	#include <linux/list.h>
04713306	16	#include <linux/module.h>
fd81d7e9	17	#include <linux/property.h>
04713306	18	#include <linux/slab.h>
c72a1d60	19	#include <linux/spinlock.h>
9067359f	20	#include <linux/timer.h>
eb1ce746	21	#include <uapi/linux/uleds.h>
699a8c7c	22	#include <linux/of.h>
c72a1d60 RP	23	#include "leds.h"
	24
	25	static struct class *leds_class;
	26
5baa7503	27	static ssize_t brightness_show(struct device *dev,
f8a7c6fe	28	struct device_attribute attr, char buf)
c72a1d60	29	{
f8a7c6fe	30	struct led_classdev *led_cdev = dev_get_drvdata(dev);
c72a1d60 RP	31
c72a1d60 RP	32	/* no lock needed for this */
29d76dfa	33	led_update_brightness(led_cdev);
c72a1d60	34
dd8e5a20	35	return sprintf(buf, "%u\n", led_cdev->brightness);
c72a1d60 RP	36	}
c72a1d60 RP	37
5baa7503	38	static ssize_t brightness_store(struct device *dev,
f8a7c6fe	39	struct device_attribute attr, const char buf, size_t size)
c72a1d60	40	{
f8a7c6fe	41	struct led_classdev *led_cdev = dev_get_drvdata(dev);
872b86be	42	unsigned long state;
acd899e4 JA	43	ssize_t ret;
	44
	45	mutex_lock(&led_cdev->led_access);
	46
	47	if (led_sysfs_is_disabled(led_cdev)) {
	48	ret = -EBUSY;
	49	goto unlock;
	50	}
c72a1d60	51
872b86be SK	52	ret = kstrtoul(buf, 10, &state);
872b86be SK	53	if (ret)
acd899e4	54	goto unlock;
3dc7b82e	55
872b86be SK	56	if (state == LED_OFF)
872b86be SK	57	led_trigger_remove(led_cdev);
4d71a4a1	58	led_set_brightness(led_cdev, state);
0db37915	59	flush_work(&led_cdev->set_brightness_work);
0013b23d	60
acd899e4 JA	61	ret = size;
	62	unlock:
	63	mutex_unlock(&led_cdev->led_access);
	64	return ret;
c72a1d60	65	}
5baa7503	66	static DEVICE_ATTR_RW(brightness);
c72a1d60	67
38419612	68	static ssize_t max_brightness_show(struct device *dev,
1bd465e6 GL	69	struct device_attribute attr, char buf)
	70	{
	71	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	72
	73	return sprintf(buf, "%u\n", led_cdev->max_brightness);
	74	}
38419612	75	static DEVICE_ATTR_RO(max_brightness);
1bd465e6	76
c3bc9956	77	#ifdef CONFIG_LEDS_TRIGGERS
11f70002 AM	78	static BIN_ATTR(trigger, 0644, led_trigger_read, led_trigger_write, 0);
	79	static struct bin_attribute *led_trigger_bin_attrs[] = {
	80	&bin_attr_trigger,
5baa7503 GKH	81	NULL,
	82	};
	83	static const struct attribute_group led_trigger_group = {
11f70002	84	.bin_attrs = led_trigger_bin_attrs,
5baa7503 GKH	85	};
	86	#endif
	87
	88	static struct attribute *led_class_attrs[] = {
	89	&dev_attr_brightness.attr,
	90	&dev_attr_max_brightness.attr,
	91	NULL,
	92	};
	93
	94	static const struct attribute_group led_group = {
	95	.attrs = led_class_attrs,
	96	};
	97
	98	static const struct attribute_group *led_groups[] = {
	99	&led_group,
	100	#ifdef CONFIG_LEDS_TRIGGERS
	101	&led_trigger_group,
c3bc9956	102	#endif
5baa7503	103	NULL,
14b5d6dd	104	};
c72a1d60	105
0cb8eb30 HG	106	#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
	107	static ssize_t brightness_hw_changed_show(struct device *dev,
	108	struct device_attribute attr, char buf)
	109	{
	110	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	111
	112	if (led_cdev->brightness_hw_changed == -1)
	113	return -ENODATA;
	114
	115	return sprintf(buf, "%u\n", led_cdev->brightness_hw_changed);
	116	}
	117
	118	static DEVICE_ATTR_RO(brightness_hw_changed);
	119
	120	static int led_add_brightness_hw_changed(struct led_classdev *led_cdev)
	121	{
	122	struct device *dev = led_cdev->dev;
	123	int ret;
	124
	125	ret = device_create_file(dev, &dev_attr_brightness_hw_changed);
	126	if (ret) {
	127	dev_err(dev, "Error creating brightness_hw_changed\n");
	128	return ret;
	129	}
	130
	131	led_cdev->brightness_hw_changed_kn =
	132	sysfs_get_dirent(dev->kobj.sd, "brightness_hw_changed");
	133	if (!led_cdev->brightness_hw_changed_kn) {
	134	dev_err(dev, "Error getting brightness_hw_changed kn\n");
	135	device_remove_file(dev, &dev_attr_brightness_hw_changed);
	136	return -ENXIO;
	137	}
	138
	139	return 0;
	140	}
	141
	142	static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev)
	143	{
	144	sysfs_put(led_cdev->brightness_hw_changed_kn);
	145	device_remove_file(led_cdev->dev, &dev_attr_brightness_hw_changed);
	146	}
	147
af0bfab9	148	void led_classdev_notify_brightness_hw_changed(struct led_classdev *led_cdev, unsigned int brightness)
0cb8eb30 HG	149	{
	150	if (WARN_ON(!led_cdev->brightness_hw_changed_kn))
	151	return;
	152
	153	led_cdev->brightness_hw_changed = brightness;
	154	sysfs_notify_dirent(led_cdev->brightness_hw_changed_kn);
	155	}
	156	EXPORT_SYMBOL_GPL(led_classdev_notify_brightness_hw_changed);
	157	#else
	158	static int led_add_brightness_hw_changed(struct led_classdev *led_cdev)
	159	{
	160	return 0;
	161	}
	162	static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev)
	163	{
	164	}
	165	#endif
	166
c72a1d60 RP	167	/**
	168	* led_classdev_suspend - suspend an led_classdev.
	169	* @led_cdev: the led_classdev to suspend.
	170	*/
	171	void led_classdev_suspend(struct led_classdev *led_cdev)
	172	{
	173	led_cdev->flags \|= LED_SUSPENDED;
81fe8e5b	174	led_set_brightness_nopm(led_cdev, 0);
302a085c	175	flush_work(&led_cdev->set_brightness_work);
c72a1d60 RP	176	}
	177	EXPORT_SYMBOL_GPL(led_classdev_suspend);
	178
	179	/**
	180	* led_classdev_resume - resume an led_classdev.
	181	* @led_cdev: the led_classdev to resume.
	182	*/
	183	void led_classdev_resume(struct led_classdev *led_cdev)
	184	{
81fe8e5b	185	led_set_brightness_nopm(led_cdev, led_cdev->brightness);
7aea8389 JA	186
	187	if (led_cdev->flash_resume)
	188	led_cdev->flash_resume(led_cdev);
	189
c72a1d60 RP	190	led_cdev->flags &= ~LED_SUSPENDED;
	191	}
	192	EXPORT_SYMBOL_GPL(led_classdev_resume);
	193
084609bf	194	#ifdef CONFIG_PM_SLEEP
73e1ab41	195	static int led_suspend(struct device *dev)
859cb7f2 RP	196	{
	197	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	198
	199	if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
	200	led_classdev_suspend(led_cdev);
	201
	202	return 0;
	203	}
	204
	205	static int led_resume(struct device *dev)
	206	{
	207	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	208
	209	if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
	210	led_classdev_resume(led_cdev);
	211
	212	return 0;
	213	}
084609bf	214	#endif
859cb7f2	215
084609bf	216	static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
73e1ab41	217
699a8c7c TV	218	/**
	219	* of_led_get() - request a LED device via the LED framework
	220	* @np: device node to get the LED device from
	221	* @index: the index of the LED
	222	*
	223	* Returns the LED device parsed from the phandle specified in the "leds"
	224	* property of a device tree node or a negative error-code on failure.
	225	*/
	226	struct led_classdev of_led_get(struct device_node np, int index)
	227	{
	228	struct device *led_dev;
	229	struct led_classdev *led_cdev;
	230	struct device_node *led_node;
	231
	232	led_node = of_parse_phandle(np, "leds", index);
	233	if (!led_node)
	234	return ERR_PTR(-ENOENT);
	235
	236	led_dev = class_find_device_by_of_node(leds_class, led_node);
	237	of_node_put(led_node);
	238
	239	if (!led_dev)
	240	return ERR_PTR(-EPROBE_DEFER);
	241
	242	led_cdev = dev_get_drvdata(led_dev);
	243
	244	if (!try_module_get(led_cdev->dev->parent->driver->owner))
	245	return ERR_PTR(-ENODEV);
	246
	247	return led_cdev;
	248	}
	249	EXPORT_SYMBOL_GPL(of_led_get);
	250
	251	/**
	252	* led_put() - release a LED device
	253	* @led_cdev: LED device
	254	*/
	255	void led_put(struct led_classdev *led_cdev)
	256	{
	257	module_put(led_cdev->dev->parent->driver->owner);
	258	}
	259	EXPORT_SYMBOL_GPL(led_put);
	260
e389240a JJH	261	static void devm_led_release(struct device dev, void res)
	262	{
	263	struct led_classdev **p = res;
	264
	265	led_put(*p);
	266	}
	267
	268	/**
	269	* devm_of_led_get - Resource-managed request of a LED device
	270	* @dev: LED consumer
	271	* @index: index of the LED to obtain in the consumer
	272	*
	273	* The device node of the device is parse to find the request LED device.
	274	* The LED device returned from this function is automatically released
	275	* on driver detach.
	276	*
	277	* @return a pointer to a LED device or ERR_PTR(errno) on failure.
	278	*/
	279	struct led_classdev __must_check devm_of_led_get(struct device dev,
	280	int index)
	281	{
	282	struct led_classdev *led;
	283	struct led_classdev **dr;
	284
	285	if (!dev)
	286	return ERR_PTR(-EINVAL);
	287
e389240a JJH	288	led = of_led_get(dev->of_node, index);
	289	if (IS_ERR(led))
	290	return led;
	291
	292	dr = devres_alloc(devm_led_release, sizeof(struct led_classdev *),
	293	GFP_KERNEL);
	294	if (!dr) {
	295	led_put(led);
	296	return ERR_PTR(-ENOMEM);
	297	}
	298
	299	*dr = led;
	300	devres_add(dev, dr);
	301
	302	return led;
	303	}
	304	EXPORT_SYMBOL_GPL(devm_of_led_get);
	305
a96aa64c RRD	306	static int led_classdev_next_name(const char init_name, char name,
	307	size_t len)
	308	{
	309	unsigned int i = 0;
	310	int ret = 0;
e5b5a61f	311	struct device *dev;
a96aa64c RRD	312
	313	strlcpy(name, init_name, len);
	314
e5b5a61f	315	while ((ret < len) &&
6cda08a2	316	(dev = class_find_device_by_name(leds_class, name))) {
e5b5a61f	317	put_device(dev);
a96aa64c	318	ret = snprintf(name, len, "%s_%u", init_name, ++i);
e5b5a61f	319	}
a96aa64c RRD	320
	321	if (ret >= len)
	322	return -ENOMEM;
	323
	324	return i;
	325	}
	326
c72a1d60	327	/**
b2b998c0 JA	328	* led_classdev_register_ext - register a new object of led_classdev class
b2b998c0 JA	329	* with init data.
442c6098 RM	330	*
442c6098 RM	331	* @parent: parent of LED device
c72a1d60	332	* @led_cdev: the led_classdev structure for this device.
b2b998c0	333	* @init_data: LED class device initialization data
c72a1d60	334	*/
b2b998c0 JA	335	int led_classdev_register_ext(struct device *parent,
	336	struct led_classdev *led_cdev,
	337	struct led_init_data *init_data)
c72a1d60	338	{
bb4e9af0 JA	339	char composed_name[LED_MAX_NAME_SIZE];
	340	char final_name[LED_MAX_NAME_SIZE];
	341	const char *proposed_name = composed_name;
a96aa64c RRD	342	int ret;
a96aa64c RRD	343
bb4e9af0 JA	344	if (init_data) {
	345	if (init_data->devname_mandatory && !init_data->devicename) {
	346	dev_err(parent, "Mandatory device name is missing");
	347	return -EINVAL;
	348	}
	349	ret = led_compose_name(parent, init_data, composed_name);
	350	if (ret < 0)
	351	return ret;
c49d6cab	352
41906632	353	if (init_data->fwnode) {
c49d6cab MB	354	fwnode_property_read_string(init_data->fwnode,
	355	"linux,default-trigger",
	356	&led_cdev->default_trigger);
41906632 EJ	357
	358	if (fwnode_property_present(init_data->fwnode,
	359	"retain-state-shutdown"))
	360	led_cdev->flags \|= LED_RETAIN_AT_SHUTDOWN;
	361	}
bb4e9af0 JA	362	} else {
	363	proposed_name = led_cdev->name;
	364	}
	365
	366	ret = led_classdev_next_name(proposed_name, final_name, sizeof(final_name));
a96aa64c RRD	367	if (ret < 0)
	368	return ret;
	369
6d71021a LH	370	mutex_init(&led_cdev->led_access);
6d71021a LH	371	mutex_lock(&led_cdev->led_access);
d0d480cc	372	led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
bb4e9af0	373	led_cdev, led_cdev->groups, "%s", final_name);
6d71021a LH	374	if (IS_ERR(led_cdev->dev)) {
6d71021a LH	375	mutex_unlock(&led_cdev->led_access);
f8a7c6fe	376	return PTR_ERR(led_cdev->dev);
6d71021a	377	}
495b8966 SV	378	if (init_data && init_data->fwnode)
495b8966 SV	379	device_set_node(led_cdev->dev, init_data->fwnode);
c72a1d60	380
a96aa64c	381	if (ret)
6f06c7f8	382	dev_warn(parent, "Led %s renamed to %s due to name collision",
64ed6588	383	proposed_name, dev_name(led_cdev->dev));
a96aa64c	384
0cb8eb30 HG	385	if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) {
	386	ret = led_add_brightness_hw_changed(led_cdev);
	387	if (ret) {
	388	device_unregister(led_cdev->dev);
1dbb9fb4	389	led_cdev->dev = NULL;
6d71021a	390	mutex_unlock(&led_cdev->led_access);
0cb8eb30 HG	391	return ret;
	392	}
	393	}
	394
a9c6ce57	395	led_cdev->work_flags = 0;
270c3957 RP	396	#ifdef CONFIG_LEDS_TRIGGERS
270c3957 RP	397	init_rwsem(&led_cdev->trigger_lock);
0cb8eb30 HG	398	#endif
	399	#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
	400	led_cdev->brightness_hw_changed = -1;
270c3957	401	#endif
c72a1d60	402	/* add to the list of leds */
72f8da32	403	down_write(&leds_list_lock);
c72a1d60	404	list_add_tail(&led_cdev->node, &leds_list);
72f8da32	405	up_write(&leds_list_lock);
c72a1d60	406
1bd465e6 GL	407	if (!led_cdev->max_brightness)
	408	led_cdev->max_brightness = LED_FULL;
	409
29d76dfa HMH	410	led_update_brightness(led_cdev);
29d76dfa HMH	411
757b06ae	412	led_init_core(led_cdev);
5ada28bf	413
c3bc9956	414	#ifdef CONFIG_LEDS_TRIGGERS
12fda168	415	led_trigger_set_default(led_cdev);
c3bc9956 RP	416	#endif
c3bc9956 RP	417
6d71021a LH	418	mutex_unlock(&led_cdev->led_access);
6d71021a LH	419
d23e7b8b	420	dev_dbg(parent, "Registered led device: %s\n",
f8a7c6fe	421	led_cdev->name);
c72a1d60 RP	422
	423	return 0;
	424	}
b2b998c0	425	EXPORT_SYMBOL_GPL(led_classdev_register_ext);
c72a1d60 RP	426
c72a1d60 RP	427	/**
0266a458	428	* led_classdev_unregister - unregisters a object of led_properties class.
70d63ccc	429	* @led_cdev: the led device to unregister
c72a1d60 RP	430	*
	431	* Unregisters a previously registered via led_classdev_register object.
	432	*/
b844eba2	433	void led_classdev_unregister(struct led_classdev *led_cdev)
c72a1d60	434	{
1dbb9fb4 AS	435	if (IS_ERR_OR_NULL(led_cdev->dev))
	436	return;
	437
c3bc9956	438	#ifdef CONFIG_LEDS_TRIGGERS
dc47206e	439	down_write(&led_cdev->trigger_lock);
c3bc9956 RP	440	if (led_cdev->trigger)
c3bc9956 RP	441	led_trigger_set(led_cdev, NULL);
dc47206e	442	up_write(&led_cdev->trigger_lock);
c3bc9956	443	#endif
c72a1d60	444
d84d80f3 HK	445	led_cdev->flags \|= LED_UNREGISTERING;
d84d80f3 HK	446
5ada28bf	447	/* Stop blinking */
d23a22a7	448	led_stop_software_blink(led_cdev);
d1aa577f	449
41906632 EJ	450	if (!(led_cdev->flags & LED_RETAIN_AT_SHUTDOWN))
41906632 EJ	451	led_set_brightness(led_cdev, LED_OFF);
5ada28bf	452
d1aa577f MK	453	flush_work(&led_cdev->set_brightness_work);
d1aa577f MK	454
0cb8eb30 HG	455	if (led_cdev->flags & LED_BRIGHT_HW_CHANGED)
	456	led_remove_brightness_hw_changed(led_cdev);
	457
b844eba2	458	device_unregister(led_cdev->dev);
c72a1d60	459
72f8da32	460	down_write(&leds_list_lock);
c72a1d60	461	list_del(&led_cdev->node);
72f8da32	462	up_write(&leds_list_lock);
acd899e4 JA	463
acd899e4 JA	464	mutex_destroy(&led_cdev->led_access);
c72a1d60	465	}
b844eba2	466	EXPORT_SYMBOL_GPL(led_classdev_unregister);
c72a1d60	467
ca1bb4ee BA	468	static void devm_led_classdev_release(struct device dev, void res)
	469	{
	470	led_classdev_unregister((struct led_classdev *)res);
	471	}
	472
	473	/**
b2b998c0	474	* devm_led_classdev_register_ext - resource managed led_classdev_register_ext()
442c6098 RM	475	*
442c6098 RM	476	* @parent: parent of LED device
ca1bb4ee	477	* @led_cdev: the led_classdev structure for this device.
b2b998c0	478	* @init_data: LED class device initialization data
ca1bb4ee	479	*/
b2b998c0 JA	480	int devm_led_classdev_register_ext(struct device *parent,
	481	struct led_classdev *led_cdev,
	482	struct led_init_data *init_data)
ca1bb4ee BA	483	{
	484	struct led_classdev **dr;
	485	int rc;
	486
	487	dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL);
	488	if (!dr)
	489	return -ENOMEM;
	490
b2b998c0	491	rc = led_classdev_register_ext(parent, led_cdev, init_data);
ca1bb4ee BA	492	if (rc) {
	493	devres_free(dr);
	494	return rc;
	495	}
	496
	497	*dr = led_cdev;
	498	devres_add(parent, dr);
	499
	500	return 0;
	501	}
b2b998c0	502	EXPORT_SYMBOL_GPL(devm_led_classdev_register_ext);
ca1bb4ee BA	503
	504	static int devm_led_classdev_match(struct device dev, void res, void *data)
	505	{
4b83cf07	506	struct led_classdev **p = res;
ca1bb4ee BA	507
	508	if (WARN_ON(!p \|\| !*p))
	509	return 0;
	510
	511	return *p == data;
	512	}
	513
	514	/**
	515	* devm_led_classdev_unregister() - resource managed led_classdev_unregister()
6a3a871b	516	* @dev: The device to unregister.
ca1bb4ee BA	517	* @led_cdev: the led_classdev structure for this device.
	518	*/
	519	void devm_led_classdev_unregister(struct device *dev,
	520	struct led_classdev *led_cdev)
	521	{
	522	WARN_ON(devres_release(dev,
	523	devm_led_classdev_release,
	524	devm_led_classdev_match, led_cdev));
	525	}
	526	EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);
	527
c72a1d60 RP	528	static int __init leds_init(void)
	529	{
	530	leds_class = class_create(THIS_MODULE, "leds");
	531	if (IS_ERR(leds_class))
	532	return PTR_ERR(leds_class);
73e1ab41	533	leds_class->pm = &leds_class_dev_pm_ops;
5baa7503	534	leds_class->dev_groups = led_groups;
c72a1d60 RP	535	return 0;
	536	}
	537
	538	static void __exit leds_exit(void)
	539	{
	540	class_destroy(leds_class);
	541	}
	542
	543	subsys_initcall(leds_init);
	544	module_exit(leds_exit);
	545
	546	MODULE_AUTHOR("John Lenz, Richard Purdie");
	547	MODULE_LICENSE("GPL");
	548	MODULE_DESCRIPTION("LED Class Interface");