[linux-2.6-block.git] / drivers / leds / led-core.c

/*
 * LED Class Core
 *
 * Copyright 2005-2006 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/kernel.h>
#include <linux/leds.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/rwsem.h>
#include "leds.h"

DECLARE_RWSEM(leds_list_lock);
EXPORT_SYMBOL_GPL(leds_list_lock);

LIST_HEAD(leds_list);
EXPORT_SYMBOL_GPL(leds_list);

static void led_timer_function(unsigned long data)
{
	struct led_classdev *led_cdev = (void *)data;
	unsigned long brightness;
	unsigned long delay;

	if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
		led_set_brightness_async(led_cdev, LED_OFF);
		return;
	}

	if (led_cdev->flags & LED_BLINK_ONESHOT_STOP) {
		led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP;
		return;
	}

	brightness = led_get_brightness(led_cdev);
	if (!brightness) {
		/* Time to switch the LED on. */
		brightness = led_cdev->blink_brightness;
		delay = led_cdev->blink_delay_on;
	} else {
		/* Store the current brightness value to be able
		 * to restore it when the delay_off period is over.
		 * Do it only if there is no pending blink brightness
		 * change, to avoid overwriting the new value.
		 */
		if (!(led_cdev->flags & LED_BLINK_BRIGHTNESS_CHANGE))
			led_cdev->blink_brightness = brightness;
		else
			led_cdev->flags &= ~LED_BLINK_BRIGHTNESS_CHANGE;
		brightness = LED_OFF;
		delay = led_cdev->blink_delay_off;
	}

	led_set_brightness_async(led_cdev, brightness);

	/* Return in next iteration if led is in one-shot mode and we are in
	 * the final blink state so that the led is toggled each delay_on +
	 * delay_off milliseconds in worst case.
	 */
	if (led_cdev->flags & LED_BLINK_ONESHOT) {
		if (led_cdev->flags & LED_BLINK_INVERT) {
			if (brightness)
				led_cdev->flags |= LED_BLINK_ONESHOT_STOP;
		} else {
			if (!brightness)
				led_cdev->flags |= LED_BLINK_ONESHOT_STOP;
		}
	}

	mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
}

static void set_brightness_delayed(struct work_struct *ws)
{
	struct led_classdev *led_cdev =
		container_of(ws, struct led_classdev, set_brightness_work);

	if (led_cdev->flags & LED_BLINK_DISABLE) {
		led_cdev->delayed_set_value = LED_OFF;
		led_stop_software_blink(led_cdev);
		led_cdev->flags &= ~LED_BLINK_DISABLE;
	}

	led_set_brightness_async(led_cdev, led_cdev->delayed_set_value);
}

static void led_set_software_blink(struct led_classdev *led_cdev,
				   unsigned long delay_on,
				   unsigned long delay_off)
{
	int current_brightness;

	current_brightness = led_get_brightness(led_cdev);
	if (current_brightness)
		led_cdev->blink_brightness = current_brightness;
	if (!led_cdev->blink_brightness)
		led_cdev->blink_brightness = led_cdev->max_brightness;

	led_cdev->blink_delay_on = delay_on;
	led_cdev->blink_delay_off = delay_off;

	/* never on - just set to off */
	if (!delay_on) {
		led_set_brightness_async(led_cdev, LED_OFF);
		return;
	}

	/* never off - just set to brightness */
	if (!delay_off) {
		led_set_brightness_async(led_cdev, led_cdev->blink_brightness);
		return;
	}

	mod_timer(&led_cdev->blink_timer, jiffies + 1);
}


static void led_blink_setup(struct led_classdev *led_cdev,
		     unsigned long *delay_on,
		     unsigned long *delay_off)
{
	if (!(led_cdev->flags & LED_BLINK_ONESHOT) &&
	    led_cdev->blink_set &&
	    !led_cdev->blink_set(led_cdev, delay_on, delay_off))
		return;

	/* blink with 1 Hz as default if nothing specified */
	if (!*delay_on && !*delay_off)
		*delay_on = *delay_off = 500;

	led_set_software_blink(led_cdev, *delay_on, *delay_off);
}

void led_init_core(struct led_classdev *led_cdev)
{
	INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);

	setup_timer(&led_cdev->blink_timer, led_timer_function,
		    (unsigned long)led_cdev);
}
EXPORT_SYMBOL_GPL(led_init_core);

void led_blink_set(struct led_classdev *led_cdev,
		   unsigned long *delay_on,
		   unsigned long *delay_off)
{
	del_timer_sync(&led_cdev->blink_timer);

	led_cdev->flags &= ~LED_BLINK_ONESHOT;
	led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP;

	led_blink_setup(led_cdev, delay_on, delay_off);
}
EXPORT_SYMBOL_GPL(led_blink_set);

void led_blink_set_oneshot(struct led_classdev *led_cdev,
			   unsigned long *delay_on,
			   unsigned long *delay_off,
			   int invert)
{
	if ((led_cdev->flags & LED_BLINK_ONESHOT) &&
	     timer_pending(&led_cdev->blink_timer))
		return;

	led_cdev->flags |= LED_BLINK_ONESHOT;
	led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP;

	if (invert)
		led_cdev->flags |= LED_BLINK_INVERT;
	else
		led_cdev->flags &= ~LED_BLINK_INVERT;

	led_blink_setup(led_cdev, delay_on, delay_off);
}
EXPORT_SYMBOL_GPL(led_blink_set_oneshot);

void led_stop_software_blink(struct led_classdev *led_cdev)
{
	del_timer_sync(&led_cdev->blink_timer);
	led_cdev->blink_delay_on = 0;
	led_cdev->blink_delay_off = 0;
}
EXPORT_SYMBOL_GPL(led_stop_software_blink);

void led_set_brightness(struct led_classdev *led_cdev,
			enum led_brightness brightness)
{
	int ret = 0;

	/*
	 * In case blinking is on delay brightness setting
	 * until the next timer tick.
	 */
	if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) {
		/*
		 * If we need to disable soft blinking delegate this to the
		 * work queue task to avoid problems in case we are called
		 * from hard irq context.
		 */
		if (brightness == LED_OFF) {
			led_cdev->flags |= LED_BLINK_DISABLE;
			schedule_work(&led_cdev->set_brightness_work);
		} else {
			led_cdev->flags |= LED_BLINK_BRIGHTNESS_CHANGE;
			led_cdev->blink_brightness = brightness;
		}
		return;
	}

	if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) {
		led_set_brightness_async(led_cdev, brightness);
		return;
	} else if (led_cdev->flags & SET_BRIGHTNESS_SYNC)
		ret = led_set_brightness_sync(led_cdev, brightness);
	else
		ret = -EINVAL;

	if (ret < 0)
		dev_dbg(led_cdev->dev, "Setting LED brightness failed (%d)\n",
			ret);
}
EXPORT_SYMBOL_GPL(led_set_brightness);

int led_update_brightness(struct led_classdev *led_cdev)
{
	int ret = 0;

	if (led_cdev->brightness_get) {
		ret = led_cdev->brightness_get(led_cdev);
		if (ret >= 0) {
			led_cdev->brightness = ret;
			return 0;
		}
	}

	return ret;
}
EXPORT_SYMBOL_GPL(led_update_brightness);

/* Caller must ensure led_cdev->led_access held */
void led_sysfs_disable(struct led_classdev *led_cdev)
{
	lockdep_assert_held(&led_cdev->led_access);

	led_cdev->flags |= LED_SYSFS_DISABLE;
}
EXPORT_SYMBOL_GPL(led_sysfs_disable);

/* Caller must ensure led_cdev->led_access held */
void led_sysfs_enable(struct led_classdev *led_cdev)
{
	lockdep_assert_held(&led_cdev->led_access);

	led_cdev->flags &= ~LED_SYSFS_DISABLE;
}
EXPORT_SYMBOL_GPL(led_sysfs_enable);
Commit	Line	Data
c72a1d60 RP	1	/*
	2	* LED Class Core
	3	*
	4	* Copyright 2005-2006 Openedhand Ltd.
	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
	14	#include <linux/kernel.h>
04713306	15	#include <linux/leds.h>
c72a1d60 RP	16	#include <linux/list.h>
c72a1d60 RP	17	#include <linux/module.h>
04713306	18	#include <linux/mutex.h>
72f8da32	19	#include <linux/rwsem.h>
c72a1d60 RP	20	#include "leds.h"
c72a1d60 RP	21
72f8da32	22	DECLARE_RWSEM(leds_list_lock);
4d404fd5	23	EXPORT_SYMBOL_GPL(leds_list_lock);
c72a1d60	24
4d404fd5	25	LIST_HEAD(leds_list);
c72a1d60	26	EXPORT_SYMBOL_GPL(leds_list);
a403d930	27
757b06ae JA	28	static void led_timer_function(unsigned long data)
	29	{
	30	struct led_classdev led_cdev = (void )data;
	31	unsigned long brightness;
	32	unsigned long delay;
	33
	34	if (!led_cdev->blink_delay_on \|\| !led_cdev->blink_delay_off) {
	35	led_set_brightness_async(led_cdev, LED_OFF);
	36	return;
	37	}
	38
	39	if (led_cdev->flags & LED_BLINK_ONESHOT_STOP) {
	40	led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP;
	41	return;
	42	}
	43
	44	brightness = led_get_brightness(led_cdev);
	45	if (!brightness) {
	46	/* Time to switch the LED on. */
757b06ae JA	47	brightness = led_cdev->blink_brightness;
	48	delay = led_cdev->blink_delay_on;
	49	} else {
	50	/* Store the current brightness value to be able
	51	* to restore it when the delay_off period is over.
f1e80c07 JA	52	* Do it only if there is no pending blink brightness
f1e80c07 JA	53	* change, to avoid overwriting the new value.
757b06ae	54	*/
f1e80c07 JA	55	if (!(led_cdev->flags & LED_BLINK_BRIGHTNESS_CHANGE))
	56	led_cdev->blink_brightness = brightness;
	57	else
	58	led_cdev->flags &= ~LED_BLINK_BRIGHTNESS_CHANGE;
757b06ae JA	59	brightness = LED_OFF;
	60	delay = led_cdev->blink_delay_off;
	61	}
	62
	63	led_set_brightness_async(led_cdev, brightness);
	64
	65	/* Return in next iteration if led is in one-shot mode and we are in
	66	* the final blink state so that the led is toggled each delay_on +
	67	* delay_off milliseconds in worst case.
	68	*/
	69	if (led_cdev->flags & LED_BLINK_ONESHOT) {
	70	if (led_cdev->flags & LED_BLINK_INVERT) {
	71	if (brightness)
	72	led_cdev->flags \|= LED_BLINK_ONESHOT_STOP;
	73	} else {
	74	if (!brightness)
	75	led_cdev->flags \|= LED_BLINK_ONESHOT_STOP;
	76	}
	77	}
	78
	79	mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
	80	}
	81
	82	static void set_brightness_delayed(struct work_struct *ws)
	83	{
	84	struct led_classdev *led_cdev =
	85	container_of(ws, struct led_classdev, set_brightness_work);
	86
f1e80c07 JA	87	if (led_cdev->flags & LED_BLINK_DISABLE) {
	88	led_cdev->delayed_set_value = LED_OFF;
	89	led_stop_software_blink(led_cdev);
	90	led_cdev->flags &= ~LED_BLINK_DISABLE;
	91	}
757b06ae JA	92
	93	led_set_brightness_async(led_cdev, led_cdev->delayed_set_value);
	94	}
	95
a403d930 BW	96	static void led_set_software_blink(struct led_classdev *led_cdev,
	97	unsigned long delay_on,
	98	unsigned long delay_off)
	99	{
	100	int current_brightness;
	101
	102	current_brightness = led_get_brightness(led_cdev);
	103	if (current_brightness)
	104	led_cdev->blink_brightness = current_brightness;
	105	if (!led_cdev->blink_brightness)
	106	led_cdev->blink_brightness = led_cdev->max_brightness;
	107
a403d930 BW	108	led_cdev->blink_delay_on = delay_on;
	109	led_cdev->blink_delay_off = delay_off;
	110
8d82fef8 SS	111	/* never on - just set to off */
8d82fef8 SS	112	if (!delay_on) {
4d71a4a1	113	led_set_brightness_async(led_cdev, LED_OFF);
a403d930	114	return;
8d82fef8	115	}
a403d930 BW	116
	117	/* never off - just set to brightness */
	118	if (!delay_off) {
4d71a4a1	119	led_set_brightness_async(led_cdev, led_cdev->blink_brightness);
a403d930 BW	120	return;
	121	}
	122
9067359f	123	mod_timer(&led_cdev->blink_timer, jiffies + 1);
a403d930 BW	124	}
	125
	126
20c0e6b8	127	static void led_blink_setup(struct led_classdev *led_cdev,
5bb629c5 FB	128	unsigned long *delay_on,
5bb629c5 FB	129	unsigned long *delay_off)
a403d930	130	{
5bb629c5 FB	131	if (!(led_cdev->flags & LED_BLINK_ONESHOT) &&
5bb629c5 FB	132	led_cdev->blink_set &&
a403d930 BW	133	!led_cdev->blink_set(led_cdev, delay_on, delay_off))
	134	return;
	135
	136	/* blink with 1 Hz as default if nothing specified */
	137	if (!delay_on && !delay_off)
	138	delay_on = delay_off = 500;
	139
	140	led_set_software_blink(led_cdev, delay_on, delay_off);
	141	}
5bb629c5	142
757b06ae JA	143	void led_init_core(struct led_classdev *led_cdev)
	144	{
	145	INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
	146
	147	setup_timer(&led_cdev->blink_timer, led_timer_function,
	148	(unsigned long)led_cdev);
	149	}
	150	EXPORT_SYMBOL_GPL(led_init_core);
	151
5bb629c5 FB	152	void led_blink_set(struct led_classdev *led_cdev,
	153	unsigned long *delay_on,
	154	unsigned long *delay_off)
	155	{
9067359f	156	del_timer_sync(&led_cdev->blink_timer);
5bb629c5 FB	157
	158	led_cdev->flags &= ~LED_BLINK_ONESHOT;
	159	led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP;
	160
	161	led_blink_setup(led_cdev, delay_on, delay_off);
	162	}
2806e2ff	163	EXPORT_SYMBOL_GPL(led_blink_set);
a403d930	164
5bb629c5 FB	165	void led_blink_set_oneshot(struct led_classdev *led_cdev,
	166	unsigned long *delay_on,
	167	unsigned long *delay_off,
	168	int invert)
	169	{
	170	if ((led_cdev->flags & LED_BLINK_ONESHOT) &&
9067359f	171	timer_pending(&led_cdev->blink_timer))
5bb629c5 FB	172	return;
	173
	174	led_cdev->flags \|= LED_BLINK_ONESHOT;
	175	led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP;
	176
	177	if (invert)
	178	led_cdev->flags \|= LED_BLINK_INVERT;
	179	else
	180	led_cdev->flags &= ~LED_BLINK_INVERT;
	181
	182	led_blink_setup(led_cdev, delay_on, delay_off);
	183	}
2806e2ff	184	EXPORT_SYMBOL_GPL(led_blink_set_oneshot);
5bb629c5	185
d23a22a7	186	void led_stop_software_blink(struct led_classdev *led_cdev)
a403d930	187	{
9067359f	188	del_timer_sync(&led_cdev->blink_timer);
43786482 FB	189	led_cdev->blink_delay_on = 0;
43786482 FB	190	led_cdev->blink_delay_off = 0;
d23a22a7 FB	191	}
	192	EXPORT_SYMBOL_GPL(led_stop_software_blink);
	193
	194	void led_set_brightness(struct led_classdev *led_cdev,
	195	enum led_brightness brightness)
	196	{
4d71a4a1 JA	197	int ret = 0;
4d71a4a1 JA	198
f1e80c07 JA	199	/*
	200	* In case blinking is on delay brightness setting
	201	* until the next timer tick.
	202	*/
d23a22a7	203	if (led_cdev->blink_delay_on \|\| led_cdev->blink_delay_off) {
f1e80c07 JA	204	/*
	205	* If we need to disable soft blinking delegate this to the
	206	* work queue task to avoid problems in case we are called
	207	* from hard irq context.
	208	*/
	209	if (brightness == LED_OFF) {
	210	led_cdev->flags \|= LED_BLINK_DISABLE;
76931edd	211	schedule_work(&led_cdev->set_brightness_work);
f1e80c07 JA	212	} else {
	213	led_cdev->flags \|= LED_BLINK_BRIGHTNESS_CHANGE;
	214	led_cdev->blink_brightness = brightness;
	215	}
d23a22a7 FB	216	return;
d23a22a7 FB	217	}
43786482	218
4d71a4a1 JA	219	if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) {
	220	led_set_brightness_async(led_cdev, brightness);
	221	return;
	222	} else if (led_cdev->flags & SET_BRIGHTNESS_SYNC)
	223	ret = led_set_brightness_sync(led_cdev, brightness);
	224	else
	225	ret = -EINVAL;
	226
	227	if (ret < 0)
	228	dev_dbg(led_cdev->dev, "Setting LED brightness failed (%d)\n",
	229	ret);
a403d930	230	}
2806e2ff	231	EXPORT_SYMBOL_GPL(led_set_brightness);
3ef7de53 JA	232
	233	int led_update_brightness(struct led_classdev *led_cdev)
	234	{
	235	int ret = 0;
	236
	237	if (led_cdev->brightness_get) {
	238	ret = led_cdev->brightness_get(led_cdev);
	239	if (ret >= 0) {
	240	led_cdev->brightness = ret;
	241	return 0;
	242	}
	243	}
	244
	245	return ret;
	246	}
2806e2ff	247	EXPORT_SYMBOL_GPL(led_update_brightness);
acd899e4 JA	248
	249	/* Caller must ensure led_cdev->led_access held */
	250	void led_sysfs_disable(struct led_classdev *led_cdev)
	251	{
	252	lockdep_assert_held(&led_cdev->led_access);
	253
	254	led_cdev->flags \|= LED_SYSFS_DISABLE;
	255	}
	256	EXPORT_SYMBOL_GPL(led_sysfs_disable);
	257
	258	/* Caller must ensure led_cdev->led_access held */
	259	void led_sysfs_enable(struct led_classdev *led_cdev)
	260	{
	261	lockdep_assert_held(&led_cdev->led_access);
	262
	263	led_cdev->flags &= ~LED_SYSFS_DISABLE;
	264	}
	265	EXPORT_SYMBOL_GPL(led_sysfs_enable);