[mirror_ubuntu-eoan-kernel.git] / drivers / leds / led-triggers.c

/*
 * LED Triggers Core
 *
 * Copyright 2005-2007 Openedhand Ltd.
 *
 * Author: Richard Purdie <rpurdie@openedhand.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/timer.h>
#include <linux/rwsem.h>
#include <linux/leds.h>
#include <linux/slab.h>
#include "leds.h"

/*
 * Nests outside led_cdev->trigger_lock
 */
static DECLARE_RWSEM(triggers_list_lock);
LIST_HEAD(trigger_list);

 /* Used by LED Class */

ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct led_trigger *trig;
	int ret = count;

	mutex_lock(&led_cdev->led_access);

	if (led_sysfs_is_disabled(led_cdev)) {
		ret = -EBUSY;
		goto unlock;
	}

	if (sysfs_streq(buf, "none")) {
		led_trigger_remove(led_cdev);
		goto unlock;
	}

	down_read(&triggers_list_lock);
	list_for_each_entry(trig, &trigger_list, next_trig) {
		if (sysfs_streq(buf, trig->name)) {
			down_write(&led_cdev->trigger_lock);
			led_trigger_set(led_cdev, trig);
			up_write(&led_cdev->trigger_lock);

			up_read(&triggers_list_lock);
			goto unlock;
		}
	}
	/* we come here only if buf matches no trigger */
	ret = -EINVAL;
	up_read(&triggers_list_lock);

unlock:
	mutex_unlock(&led_cdev->led_access);
	return ret;
}
EXPORT_SYMBOL_GPL(led_trigger_store);

ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct led_trigger *trig;
	int len = 0;

	down_read(&triggers_list_lock);
	down_read(&led_cdev->trigger_lock);

	if (!led_cdev->trigger)
		len += scnprintf(buf+len, PAGE_SIZE - len, "[none] ");
	else
		len += scnprintf(buf+len, PAGE_SIZE - len, "none ");

	list_for_each_entry(trig, &trigger_list, next_trig) {
		if (led_cdev->trigger && !strcmp(led_cdev->trigger->name,
							trig->name))
			len += scnprintf(buf+len, PAGE_SIZE - len, "[%s] ",
					 trig->name);
		else
			len += scnprintf(buf+len, PAGE_SIZE - len, "%s ",
					 trig->name);
	}
	up_read(&led_cdev->trigger_lock);
	up_read(&triggers_list_lock);

	len += scnprintf(len+buf, PAGE_SIZE - len, "\n");
	return len;
}
EXPORT_SYMBOL_GPL(led_trigger_show);

/* Caller must ensure led_cdev->trigger_lock held */
int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
{
	unsigned long flags;
	char *event = NULL;
	char *envp[2];
	const char *name;
	int ret;

	if (!led_cdev->trigger && !trig)
		return 0;

	name = trig ? trig->name : "none";
	event = kasprintf(GFP_KERNEL, "TRIGGER=%s", name);

	/* Remove any existing trigger */
	if (led_cdev->trigger) {
		write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
		list_del(&led_cdev->trig_list);
		write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock,
			flags);
		cancel_work_sync(&led_cdev->set_brightness_work);
		led_stop_software_blink(led_cdev);
		if (led_cdev->trigger->deactivate)
			led_cdev->trigger->deactivate(led_cdev);
		device_remove_groups(led_cdev->dev, led_cdev->trigger->groups);
		led_cdev->trigger = NULL;
		led_cdev->trigger_data = NULL;
		led_cdev->activated = false;
		led_set_brightness(led_cdev, LED_OFF);
	}
	if (trig) {
		write_lock_irqsave(&trig->leddev_list_lock, flags);
		list_add_tail(&led_cdev->trig_list, &trig->led_cdevs);
		write_unlock_irqrestore(&trig->leddev_list_lock, flags);
		led_cdev->trigger = trig;

		if (trig->activate)
			ret = trig->activate(led_cdev);
		else
			ret = 0;

		if (ret)
			goto err_activate;

		ret = device_add_groups(led_cdev->dev, trig->groups);
		if (ret) {
			dev_err(led_cdev->dev, "Failed to add trigger attributes\n");
			goto err_add_groups;
		}
	}

	if (event) {
		envp[0] = event;
		envp[1] = NULL;
		if (kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp))
			dev_err(led_cdev->dev,
				"%s: Error sending uevent\n", __func__);
		kfree(event);
	}

	return 0;

err_add_groups:

	if (trig->deactivate)
		trig->deactivate(led_cdev);
err_activate:

	led_cdev->trigger = NULL;
	led_cdev->trigger_data = NULL;
	write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
	list_del(&led_cdev->trig_list);
	write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock, flags);
	led_set_brightness(led_cdev, LED_OFF);

	return ret;
}
EXPORT_SYMBOL_GPL(led_trigger_set);

void led_trigger_remove(struct led_classdev *led_cdev)
{
	down_write(&led_cdev->trigger_lock);
	led_trigger_set(led_cdev, NULL);
	up_write(&led_cdev->trigger_lock);
}
EXPORT_SYMBOL_GPL(led_trigger_remove);

void led_trigger_set_default(struct led_classdev *led_cdev)
{
	struct led_trigger *trig;

	if (!led_cdev->default_trigger)
		return;

	down_read(&triggers_list_lock);
	down_write(&led_cdev->trigger_lock);
	list_for_each_entry(trig, &trigger_list, next_trig) {
		if (!strcmp(led_cdev->default_trigger, trig->name)) {
			led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER;
			led_trigger_set(led_cdev, trig);
			break;
		}
	}
	up_write(&led_cdev->trigger_lock);
	up_read(&triggers_list_lock);
}
EXPORT_SYMBOL_GPL(led_trigger_set_default);

void led_trigger_rename_static(const char *name, struct led_trigger *trig)
{
	/* new name must be on a temporary string to prevent races */
	BUG_ON(name == trig->name);

	down_write(&triggers_list_lock);
	/* this assumes that trig->name was originaly allocated to
	 * non constant storage */
	strcpy((char *)trig->name, name);
	up_write(&triggers_list_lock);
}
EXPORT_SYMBOL_GPL(led_trigger_rename_static);

/* LED Trigger Interface */

int led_trigger_register(struct led_trigger *trig)
{
	struct led_classdev *led_cdev;
	struct led_trigger *_trig;

	rwlock_init(&trig->leddev_list_lock);
	INIT_LIST_HEAD(&trig->led_cdevs);

	down_write(&triggers_list_lock);
	/* Make sure the trigger's name isn't already in use */
	list_for_each_entry(_trig, &trigger_list, next_trig) {
		if (!strcmp(_trig->name, trig->name)) {
			up_write(&triggers_list_lock);
			return -EEXIST;
		}
	}
	/* Add to the list of led triggers */
	list_add_tail(&trig->next_trig, &trigger_list);
	up_write(&triggers_list_lock);

	/* Register with any LEDs that have this as a default trigger */
	down_read(&leds_list_lock);
	list_for_each_entry(led_cdev, &leds_list, node) {
		down_write(&led_cdev->trigger_lock);
		if (!led_cdev->trigger && led_cdev->default_trigger &&
			    !strcmp(led_cdev->default_trigger, trig->name))
			led_trigger_set(led_cdev, trig);
		up_write(&led_cdev->trigger_lock);
	}
	up_read(&leds_list_lock);

	return 0;
}
EXPORT_SYMBOL_GPL(led_trigger_register);

void led_trigger_unregister(struct led_trigger *trig)
{
	struct led_classdev *led_cdev;

	if (list_empty_careful(&trig->next_trig))
		return;

	/* Remove from the list of led triggers */
	down_write(&triggers_list_lock);
	list_del_init(&trig->next_trig);
	up_write(&triggers_list_lock);

	/* Remove anyone actively using this trigger */
	down_read(&leds_list_lock);
	list_for_each_entry(led_cdev, &leds_list, node) {
		down_write(&led_cdev->trigger_lock);
		if (led_cdev->trigger == trig)
			led_trigger_set(led_cdev, NULL);
		up_write(&led_cdev->trigger_lock);
	}
	up_read(&leds_list_lock);
}
EXPORT_SYMBOL_GPL(led_trigger_unregister);

static void devm_led_trigger_release(struct device *dev, void *res)
{
	led_trigger_unregister(*(struct led_trigger **)res);
}

int devm_led_trigger_register(struct device *dev,
			      struct led_trigger *trig)
{
	struct led_trigger **dr;
	int rc;

	dr = devres_alloc(devm_led_trigger_release, sizeof(*dr),
			  GFP_KERNEL);
	if (!dr)
		return -ENOMEM;

	*dr = trig;

	rc = led_trigger_register(trig);
	if (rc)
		devres_free(dr);
	else
		devres_add(dev, dr);

	return rc;
}
EXPORT_SYMBOL_GPL(devm_led_trigger_register);

/* Simple LED Tigger Interface */

void led_trigger_event(struct led_trigger *trig,
			enum led_brightness brightness)
{
	struct led_classdev *led_cdev;

	if (!trig)
		return;

	read_lock(&trig->leddev_list_lock);
	list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list)
		led_set_brightness(led_cdev, brightness);
	read_unlock(&trig->leddev_list_lock);
}
EXPORT_SYMBOL_GPL(led_trigger_event);

static void led_trigger_blink_setup(struct led_trigger *trig,
			     unsigned long *delay_on,
			     unsigned long *delay_off,
			     int oneshot,
			     int invert)
{
	struct led_classdev *led_cdev;

	if (!trig)
		return;

	read_lock(&trig->leddev_list_lock);
	list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) {
		if (oneshot)
			led_blink_set_oneshot(led_cdev, delay_on, delay_off,
					      invert);
		else
			led_blink_set(led_cdev, delay_on, delay_off);
	}
	read_unlock(&trig->leddev_list_lock);
}

void led_trigger_blink(struct led_trigger *trig,
		       unsigned long *delay_on,
		       unsigned long *delay_off)
{
	led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0);
}
EXPORT_SYMBOL_GPL(led_trigger_blink);

void led_trigger_blink_oneshot(struct led_trigger *trig,
			       unsigned long *delay_on,
			       unsigned long *delay_off,
			       int invert)
{
	led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert);
}
EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot);

void led_trigger_register_simple(const char *name, struct led_trigger **tp)
{
	struct led_trigger *trig;
	int err;

	trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);

	if (trig) {
		trig->name = name;
		err = led_trigger_register(trig);
		if (err < 0) {
			kfree(trig);
			trig = NULL;
			pr_warn("LED trigger %s failed to register (%d)\n",
				name, err);
		}
	} else {
		pr_warn("LED trigger %s failed to register (no memory)\n",
			name);
	}
	*tp = trig;
}
EXPORT_SYMBOL_GPL(led_trigger_register_simple);

void led_trigger_unregister_simple(struct led_trigger *trig)
{
	if (trig)
		led_trigger_unregister(trig);
	kfree(trig);
}
EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);
Commit	Line	Data
c3bc9956 RP	1	/*
	2	* LED Triggers Core
	3	*
f8a7c6fe	4	* Copyright 2005-2007 Openedhand Ltd.
c3bc9956 RP	5	*
	6	* Author: Richard Purdie <rpurdie@openedhand.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*
	12	*/
	13
50237863	14	#include <linux/export.h>
c3bc9956	15	#include <linux/kernel.h>
c3bc9956 RP	16	#include <linux/list.h>
	17	#include <linux/spinlock.h>
	18	#include <linux/device.h>
c3bc9956	19	#include <linux/timer.h>
dc47206e	20	#include <linux/rwsem.h>
c3bc9956	21	#include <linux/leds.h>
5a0e3ad6	22	#include <linux/slab.h>
c3bc9956 RP	23	#include "leds.h"
	24
	25	/*
	26	* Nests outside led_cdev->trigger_lock
	27	*/
dc47206e	28	static DECLARE_RWSEM(triggers_list_lock);
ba93cdce	29	LIST_HEAD(trigger_list);
c3bc9956	30
4d404fd5 NM	31	/* Used by LED Class */
4d404fd5 NM	32
f8a7c6fe RP	33	ssize_t led_trigger_store(struct device dev, struct device_attribute attr,
f8a7c6fe RP	34	const char *buf, size_t count)
c3bc9956	35	{
f8a7c6fe	36	struct led_classdev *led_cdev = dev_get_drvdata(dev);
c3bc9956	37	struct led_trigger *trig;
acd899e4 JA	38	int ret = count;
	39
	40	mutex_lock(&led_cdev->led_access);
	41
	42	if (led_sysfs_is_disabled(led_cdev)) {
	43	ret = -EBUSY;
	44	goto unlock;
	45	}
c3bc9956	46
7296c33e	47	if (sysfs_streq(buf, "none")) {
0013b23d	48	led_trigger_remove(led_cdev);
acd899e4	49	goto unlock;
c3bc9956 RP	50	}
c3bc9956 RP	51
dc47206e	52	down_read(&triggers_list_lock);
c3bc9956	53	list_for_each_entry(trig, &trigger_list, next_trig) {
7296c33e	54	if (sysfs_streq(buf, trig->name)) {
dc47206e	55	down_write(&led_cdev->trigger_lock);
c3bc9956	56	led_trigger_set(led_cdev, trig);
dc47206e	57	up_write(&led_cdev->trigger_lock);
c3bc9956	58
dc47206e	59	up_read(&triggers_list_lock);
acd899e4	60	goto unlock;
c3bc9956 RP	61	}
c3bc9956 RP	62	}
a3eac76c HK	63	/* we come here only if buf matches no trigger */
a3eac76c HK	64	ret = -EINVAL;
dc47206e	65	up_read(&triggers_list_lock);
c3bc9956	66
acd899e4 JA	67	unlock:
	68	mutex_unlock(&led_cdev->led_access);
	69	return ret;
c3bc9956	70	}
4d404fd5	71	EXPORT_SYMBOL_GPL(led_trigger_store);
c3bc9956	72
f8a7c6fe RP	73	ssize_t led_trigger_show(struct device dev, struct device_attribute attr,
f8a7c6fe RP	74	char *buf)
c3bc9956	75	{
f8a7c6fe	76	struct led_classdev *led_cdev = dev_get_drvdata(dev);
c3bc9956 RP	77	struct led_trigger *trig;
	78	int len = 0;
	79
dc47206e RP	80	down_read(&triggers_list_lock);
dc47206e RP	81	down_read(&led_cdev->trigger_lock);
c3bc9956 RP	82
c3bc9956 RP	83	if (!led_cdev->trigger)
3b9b9536	84	len += scnprintf(buf+len, PAGE_SIZE - len, "[none] ");
c3bc9956	85	else
3b9b9536	86	len += scnprintf(buf+len, PAGE_SIZE - len, "none ");
c3bc9956 RP	87
	88	list_for_each_entry(trig, &trigger_list, next_trig) {
	89	if (led_cdev->trigger && !strcmp(led_cdev->trigger->name,
	90	trig->name))
3b9b9536 NS	91	len += scnprintf(buf+len, PAGE_SIZE - len, "[%s] ",
3b9b9536 NS	92	trig->name);
c3bc9956	93	else
3b9b9536 NS	94	len += scnprintf(buf+len, PAGE_SIZE - len, "%s ",
3b9b9536 NS	95	trig->name);
c3bc9956	96	}
dc47206e RP	97	up_read(&led_cdev->trigger_lock);
dc47206e RP	98	up_read(&triggers_list_lock);
c3bc9956	99
3b9b9536	100	len += scnprintf(len+buf, PAGE_SIZE - len, "\n");
c3bc9956 RP	101	return len;
c3bc9956 RP	102	}
4d404fd5	103	EXPORT_SYMBOL_GPL(led_trigger_show);
c3bc9956 RP	104
c3bc9956 RP	105	/* Caller must ensure led_cdev->trigger_lock held */
2282e125	106	int led_trigger_set(struct led_classdev led_cdev, struct led_trigger trig)
c3bc9956 RP	107	{
c3bc9956 RP	108	unsigned long flags;
52c47742 CC	109	char *event = NULL;
	110	char *envp[2];
	111	const char *name;
2282e125	112	int ret;
52c47742	113
fbfa197a	114	if (!led_cdev->trigger && !trig)
2282e125	115	return 0;
fbfa197a	116
52c47742 CC	117	name = trig ? trig->name : "none";
52c47742 CC	118	event = kasprintf(GFP_KERNEL, "TRIGGER=%s", name);
c3bc9956 RP	119
	120	/* Remove any existing trigger */
	121	if (led_cdev->trigger) {
	122	write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
	123	list_del(&led_cdev->trig_list);
4d404fd5 NM	124	write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock,
4d404fd5 NM	125	flags);
d23a22a7 FB	126	cancel_work_sync(&led_cdev->set_brightness_work);
d23a22a7 FB	127	led_stop_software_blink(led_cdev);
c3bc9956 RP	128	if (led_cdev->trigger->deactivate)
c3bc9956 RP	129	led_cdev->trigger->deactivate(led_cdev);
a7e7a315	130	device_remove_groups(led_cdev->dev, led_cdev->trigger->groups);
fe3025b5	131	led_cdev->trigger = NULL;
a7d5904a UKK	132	led_cdev->trigger_data = NULL;
a7d5904a UKK	133	led_cdev->activated = false;
19cd67e2	134	led_set_brightness(led_cdev, LED_OFF);
c3bc9956	135	}
eb202621 BW	136	if (trig) {
	137	write_lock_irqsave(&trig->leddev_list_lock, flags);
	138	list_add_tail(&led_cdev->trig_list, &trig->led_cdevs);
	139	write_unlock_irqrestore(&trig->leddev_list_lock, flags);
	140	led_cdev->trigger = trig;
2282e125	141
eb202621	142	if (trig->activate)
2282e125 UKK	143	ret = trig->activate(led_cdev);
	144	else
	145	ret = 0;
	146
	147	if (ret)
	148	goto err_activate;
a7e7a315 UKK	149
	150	ret = device_add_groups(led_cdev->dev, trig->groups);
	151	if (ret) {
	152	dev_err(led_cdev->dev, "Failed to add trigger attributes\n");
	153	goto err_add_groups;
	154	}
c3bc9956	155	}
52c47742 CC	156
	157	if (event) {
	158	envp[0] = event;
	159	envp[1] = NULL;
6f3bad96 JA	160	if (kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp))
	161	dev_err(led_cdev->dev,
	162	"%s: Error sending uevent\n", __func__);
52c47742 CC	163	kfree(event);
52c47742 CC	164	}
2282e125 UKK	165
	166	return 0;
	167
a7e7a315 UKK	168	err_add_groups:
	169
	170	if (trig->deactivate)
	171	trig->deactivate(led_cdev);
2282e125	172	err_activate:
a7e7a315	173
2282e125	174	led_cdev->trigger = NULL;
a7d5904a	175	led_cdev->trigger_data = NULL;
2282e125 UKK	176	write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
	177	list_del(&led_cdev->trig_list);
	178	write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock, flags);
	179	led_set_brightness(led_cdev, LED_OFF);
	180
	181	return ret;
c3bc9956	182	}
4d404fd5	183	EXPORT_SYMBOL_GPL(led_trigger_set);
c3bc9956	184
0013b23d NM	185	void led_trigger_remove(struct led_classdev *led_cdev)
	186	{
	187	down_write(&led_cdev->trigger_lock);
	188	led_trigger_set(led_cdev, NULL);
	189	up_write(&led_cdev->trigger_lock);
	190	}
4d404fd5	191	EXPORT_SYMBOL_GPL(led_trigger_remove);
0013b23d	192
c3bc9956 RP	193	void led_trigger_set_default(struct led_classdev *led_cdev)
	194	{
	195	struct led_trigger *trig;
	196
	197	if (!led_cdev->default_trigger)
	198	return;
	199
dc47206e RP	200	down_read(&triggers_list_lock);
dc47206e RP	201	down_write(&led_cdev->trigger_lock);
c3bc9956	202	list_for_each_entry(trig, &trigger_list, next_trig) {
c4f7bd4a	203	if (!strcmp(led_cdev->default_trigger, trig->name)) {
02d31765	204	led_cdev->flags \|= LED_INIT_DEFAULT_TRIGGER;
c3bc9956	205	led_trigger_set(led_cdev, trig);
c4f7bd4a JA	206	break;
c4f7bd4a JA	207	}
c3bc9956	208	}
dc47206e RP	209	up_write(&led_cdev->trigger_lock);
dc47206e RP	210	up_read(&triggers_list_lock);
c3bc9956	211	}
4d404fd5 NM	212	EXPORT_SYMBOL_GPL(led_trigger_set_default);
4d404fd5 NM	213
a8df7b1a FB	214	void led_trigger_rename_static(const char name, struct led_trigger trig)
	215	{
	216	/* new name must be on a temporary string to prevent races */
	217	BUG_ON(name == trig->name);
	218
	219	down_write(&triggers_list_lock);
	220	/* this assumes that trig->name was originaly allocated to
	221	* non constant storage */
	222	strcpy((char *)trig->name, name);
	223	up_write(&triggers_list_lock);
	224	}
	225	EXPORT_SYMBOL_GPL(led_trigger_rename_static);
	226
4d404fd5	227	/* LED Trigger Interface */
c3bc9956	228
eb202621	229	int led_trigger_register(struct led_trigger *trig)
c3bc9956 RP	230	{
c3bc9956 RP	231	struct led_classdev *led_cdev;
eb202621	232	struct led_trigger *_trig;
c3bc9956	233
eb202621 BW	234	rwlock_init(&trig->leddev_list_lock);
eb202621 BW	235	INIT_LIST_HEAD(&trig->led_cdevs);
c3bc9956	236
dc47206e	237	down_write(&triggers_list_lock);
700c6ea2	238	/* Make sure the trigger's name isn't already in use */
eb202621 BW	239	list_for_each_entry(_trig, &trigger_list, next_trig) {
eb202621 BW	240	if (!strcmp(_trig->name, trig->name)) {
700c6ea2 AN	241	up_write(&triggers_list_lock);
	242	return -EEXIST;
	243	}
	244	}
	245	/* Add to the list of led triggers */
eb202621	246	list_add_tail(&trig->next_trig, &trigger_list);
dc47206e	247	up_write(&triggers_list_lock);
c3bc9956 RP	248
c3bc9956 RP	249	/* Register with any LEDs that have this as a default trigger */
72f8da32	250	down_read(&leds_list_lock);
c3bc9956	251	list_for_each_entry(led_cdev, &leds_list, node) {
dc47206e	252	down_write(&led_cdev->trigger_lock);
c3bc9956	253	if (!led_cdev->trigger && led_cdev->default_trigger &&
eb202621 BW	254	!strcmp(led_cdev->default_trigger, trig->name))
eb202621 BW	255	led_trigger_set(led_cdev, trig);
dc47206e	256	up_write(&led_cdev->trigger_lock);
c3bc9956	257	}
72f8da32	258	up_read(&leds_list_lock);
c3bc9956 RP	259
	260	return 0;
	261	}
4d404fd5	262	EXPORT_SYMBOL_GPL(led_trigger_register);
c3bc9956	263
eb202621	264	void led_trigger_unregister(struct led_trigger *trig)
c3bc9956 RP	265	{
	266	struct led_classdev *led_cdev;
	267
14f5716b SL	268	if (list_empty_careful(&trig->next_trig))
	269	return;
	270
c3bc9956	271	/* Remove from the list of led triggers */
dc47206e	272	down_write(&triggers_list_lock);
14f5716b	273	list_del_init(&trig->next_trig);
dc47206e	274	up_write(&triggers_list_lock);
c3bc9956 RP	275
c3bc9956 RP	276	/* Remove anyone actively using this trigger */
72f8da32	277	down_read(&leds_list_lock);
c3bc9956	278	list_for_each_entry(led_cdev, &leds_list, node) {
dc47206e	279	down_write(&led_cdev->trigger_lock);
eb202621	280	if (led_cdev->trigger == trig)
c3bc9956	281	led_trigger_set(led_cdev, NULL);
dc47206e	282	up_write(&led_cdev->trigger_lock);
c3bc9956	283	}
72f8da32	284	up_read(&leds_list_lock);
c3bc9956	285	}
4d404fd5	286	EXPORT_SYMBOL_GPL(led_trigger_unregister);
c3bc9956	287
9534cc31 HK	288	static void devm_led_trigger_release(struct device dev, void res)
	289	{
	290	led_trigger_unregister((struct led_trigger *)res);
	291	}
	292
	293	int devm_led_trigger_register(struct device *dev,
	294	struct led_trigger *trig)
	295	{
	296	struct led_trigger **dr;
	297	int rc;
	298
	299	dr = devres_alloc(devm_led_trigger_release, sizeof(*dr),
	300	GFP_KERNEL);
	301	if (!dr)
	302	return -ENOMEM;
	303
	304	*dr = trig;
	305
	306	rc = led_trigger_register(trig);
	307	if (rc)
	308	devres_free(dr);
	309	else
	310	devres_add(dev, dr);
	311
	312	return rc;
	313	}
	314	EXPORT_SYMBOL_GPL(devm_led_trigger_register);
	315
4d404fd5 NM	316	/* Simple LED Tigger Interface */
4d404fd5 NM	317
eb202621	318	void led_trigger_event(struct led_trigger *trig,
4d404fd5	319	enum led_brightness brightness)
c3bc9956	320	{
11e043b5	321	struct led_classdev *led_cdev;
4d404fd5	322
eb202621	323	if (!trig)
4d404fd5 NM	324	return;
4d404fd5 NM	325
eb202621	326	read_lock(&trig->leddev_list_lock);
11e043b5	327	list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list)
d23a22a7	328	led_set_brightness(led_cdev, brightness);
eb202621	329	read_unlock(&trig->leddev_list_lock);
c3bc9956	330	}
4d404fd5	331	EXPORT_SYMBOL_GPL(led_trigger_event);
c3bc9956	332
20c0e6b8	333	static void led_trigger_blink_setup(struct led_trigger *trig,
5bb629c5 FB	334	unsigned long *delay_on,
	335	unsigned long *delay_off,
	336	int oneshot,
	337	int invert)
0b9536c9	338	{
11e043b5	339	struct led_classdev *led_cdev;
0b9536c9	340
eb202621	341	if (!trig)
0b9536c9 VK	342	return;
0b9536c9 VK	343
eb202621	344	read_lock(&trig->leddev_list_lock);
11e043b5	345	list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) {
5bb629c5 FB	346	if (oneshot)
	347	led_blink_set_oneshot(led_cdev, delay_on, delay_off,
	348	invert);
	349	else
	350	led_blink_set(led_cdev, delay_on, delay_off);
0b9536c9	351	}
eb202621	352	read_unlock(&trig->leddev_list_lock);
0b9536c9	353	}
5bb629c5 FB	354
	355	void led_trigger_blink(struct led_trigger *trig,
	356	unsigned long *delay_on,
	357	unsigned long *delay_off)
	358	{
	359	led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0);
	360	}
0b9536c9 VK	361	EXPORT_SYMBOL_GPL(led_trigger_blink);
0b9536c9 VK	362
5bb629c5 FB	363	void led_trigger_blink_oneshot(struct led_trigger *trig,
	364	unsigned long *delay_on,
	365	unsigned long *delay_off,
	366	int invert)
	367	{
	368	led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert);
	369	}
	370	EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot);
	371
4d404fd5 NM	372	void led_trigger_register_simple(const char name, struct led_trigger *tp)
4d404fd5 NM	373	{
eb202621	374	struct led_trigger *trig;
4d404fd5	375	int err;
c3bc9956	376
eb202621	377	trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
c3bc9956	378
eb202621 BW	379	if (trig) {
	380	trig->name = name;
	381	err = led_trigger_register(trig);
cba4c2ac	382	if (err < 0) {
eb202621 BW	383	kfree(trig);
eb202621 BW	384	trig = NULL;
09f5fe75 SK	385	pr_warn("LED trigger %s failed to register (%d)\n",
09f5fe75 SK	386	name, err);
cba4c2ac	387	}
09f5fe75 SK	388	} else {
	389	pr_warn("LED trigger %s failed to register (no memory)\n",
	390	name);
	391	}
eb202621	392	*tp = trig;
4d404fd5	393	}
c3bc9956	394	EXPORT_SYMBOL_GPL(led_trigger_register_simple);
4d404fd5	395
eb202621	396	void led_trigger_unregister_simple(struct led_trigger *trig)
4d404fd5	397	{
eb202621 BW	398	if (trig)
	399	led_trigger_unregister(trig);
	400	kfree(trig);
4d404fd5	401	}
c3bc9956	402	EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);