[linux-2.6-block.git] / drivers / leds / trigger / ledtrig-heartbeat.c

/*
 * LED Heartbeat Trigger
 *
 * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
 *
 * Based on Richard Purdie's ledtrig-timer.c and some arch's
 * CONFIG_HEARTBEAT code.
 *
 * 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/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <linux/sched.h>
#include <linux/leds.h>
#include <linux/reboot.h>
#include <linux/suspend.h>
#include "../leds.h"

static int panic_heartbeats;

struct heartbeat_trig_data {
	unsigned int phase;
	unsigned int period;
	struct timer_list timer;
	unsigned int invert;
};

static void led_heartbeat_function(unsigned long data)
{
	struct led_classdev *led_cdev = (struct led_classdev *) data;
	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	unsigned long brightness = LED_OFF;
	unsigned long delay = 0;

	if (unlikely(panic_heartbeats)) {
		led_set_brightness_nosleep(led_cdev, LED_OFF);
		return;
	}

	/* acts like an actual heart beat -- ie thump-thump-pause... */
	switch (heartbeat_data->phase) {
	case 0:
		/*
		 * The hyperbolic function below modifies the
		 * heartbeat period length in dependency of the
		 * current (1min) load. It goes through the points
		 * f(0)=1260, f(1)=860, f(5)=510, f(inf)->300.
		 */
		heartbeat_data->period = 300 +
			(6720 << FSHIFT) / (5 * avenrun[0] + (7 << FSHIFT));
		heartbeat_data->period =
			msecs_to_jiffies(heartbeat_data->period);
		delay = msecs_to_jiffies(70);
		heartbeat_data->phase++;
		if (!heartbeat_data->invert)
			brightness = led_cdev->max_brightness;
		break;
	case 1:
		delay = heartbeat_data->period / 4 - msecs_to_jiffies(70);
		heartbeat_data->phase++;
		if (heartbeat_data->invert)
			brightness = led_cdev->max_brightness;
		break;
	case 2:
		delay = msecs_to_jiffies(70);
		heartbeat_data->phase++;
		if (!heartbeat_data->invert)
			brightness = led_cdev->max_brightness;
		break;
	default:
		delay = heartbeat_data->period - heartbeat_data->period / 4 -
			msecs_to_jiffies(70);
		heartbeat_data->phase = 0;
		if (heartbeat_data->invert)
			brightness = led_cdev->max_brightness;
		break;
	}

	led_set_brightness_nosleep(led_cdev, brightness);
	mod_timer(&heartbeat_data->timer, jiffies + delay);
}

static ssize_t led_invert_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;

	return sprintf(buf, "%u\n", heartbeat_data->invert);
}

static ssize_t led_invert_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t size)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	unsigned long state;
	int ret;

	ret = kstrtoul(buf, 0, &state);
	if (ret)
		return ret;

	heartbeat_data->invert = !!state;

	return size;
}

static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store);

static void heartbeat_trig_activate(struct led_classdev *led_cdev)
{
	struct heartbeat_trig_data *heartbeat_data;
	int rc;

	heartbeat_data = kzalloc(sizeof(*heartbeat_data), GFP_KERNEL);
	if (!heartbeat_data)
		return;

	led_cdev->trigger_data = heartbeat_data;
	rc = device_create_file(led_cdev->dev, &dev_attr_invert);
	if (rc) {
		kfree(led_cdev->trigger_data);
		return;
	}

	setup_timer(&heartbeat_data->timer,
		    led_heartbeat_function, (unsigned long) led_cdev);
	heartbeat_data->phase = 0;
	led_heartbeat_function(heartbeat_data->timer.data);
	led_cdev->activated = true;
}

static void heartbeat_trig_deactivate(struct led_classdev *led_cdev)
{
	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;

	if (led_cdev->activated) {
		del_timer_sync(&heartbeat_data->timer);
		device_remove_file(led_cdev->dev, &dev_attr_invert);
		kfree(heartbeat_data);
		led_cdev->activated = false;
	}
}

static struct led_trigger heartbeat_led_trigger = {
	.name     = "heartbeat",
	.activate = heartbeat_trig_activate,
	.deactivate = heartbeat_trig_deactivate,
};

static int heartbeat_pm_notifier(struct notifier_block *nb,
				 unsigned long pm_event, void *unused)
{
	int rc;

	switch (pm_event) {
	case PM_SUSPEND_PREPARE:
	case PM_HIBERNATION_PREPARE:
	case PM_RESTORE_PREPARE:
		led_trigger_unregister(&heartbeat_led_trigger);
		break;
	case PM_POST_SUSPEND:
	case PM_POST_HIBERNATION:
	case PM_POST_RESTORE:
		rc = led_trigger_register(&heartbeat_led_trigger);
		if (rc)
			pr_err("could not re-register heartbeat trigger\n");
		break;
	default:
		break;
	}
	return NOTIFY_DONE;
}

static int heartbeat_reboot_notifier(struct notifier_block *nb,
				     unsigned long code, void *unused)
{
	led_trigger_unregister(&heartbeat_led_trigger);
	return NOTIFY_DONE;
}

static int heartbeat_panic_notifier(struct notifier_block *nb,
				     unsigned long code, void *unused)
{
	panic_heartbeats = 1;
	return NOTIFY_DONE;
}

static struct notifier_block heartbeat_pm_nb = {
	.notifier_call = heartbeat_pm_notifier,
};

static struct notifier_block heartbeat_reboot_nb = {
	.notifier_call = heartbeat_reboot_notifier,
};

static struct notifier_block heartbeat_panic_nb = {
	.notifier_call = heartbeat_panic_notifier,
};

static int __init heartbeat_trig_init(void)
{
	int rc = led_trigger_register(&heartbeat_led_trigger);

	if (!rc) {
		atomic_notifier_chain_register(&panic_notifier_list,
					       &heartbeat_panic_nb);
		register_reboot_notifier(&heartbeat_reboot_nb);
		register_pm_notifier(&heartbeat_pm_nb);
	}
	return rc;
}

static void __exit heartbeat_trig_exit(void)
{
	unregister_pm_notifier(&heartbeat_pm_nb);
	unregister_reboot_notifier(&heartbeat_reboot_nb);
	atomic_notifier_chain_unregister(&panic_notifier_list,
					 &heartbeat_panic_nb);
	led_trigger_unregister(&heartbeat_led_trigger);
}

module_init(heartbeat_trig_init);
module_exit(heartbeat_trig_exit);

MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
MODULE_DESCRIPTION("Heartbeat LED trigger");
MODULE_LICENSE("GPL");
Commit	Line	Data
891c668b AN	1	/*
	2	* LED Heartbeat Trigger
	3	*
	4	* Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
	5	*
	6	* Based on Richard Purdie's ledtrig-timer.c and some arch's
	7	* CONFIG_HEARTBEAT code.
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*
	13	*/
	14	#include <linux/module.h>
	15	#include <linux/kernel.h>
	16	#include <linux/init.h>
5a0e3ad6	17	#include <linux/slab.h>
891c668b AN	18	#include <linux/timer.h>
	19	#include <linux/sched.h>
	20	#include <linux/leds.h>
49dca5ae	21	#include <linux/reboot.h>
5ab92a7c	22	#include <linux/suspend.h>
f07fb521	23	#include "../leds.h"
891c668b	24
fb31fbeb AH	25	static int panic_heartbeats;
fb31fbeb AH	26
891c668b AN	27	struct heartbeat_trig_data {
	28	unsigned int phase;
	29	unsigned int period;
	30	struct timer_list timer;
1c7b9d0e	31	unsigned int invert;
891c668b AN	32	};
	33
	34	static void led_heartbeat_function(unsigned long data)
	35	{
	36	struct led_classdev led_cdev = (struct led_classdev ) data;
	37	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	38	unsigned long brightness = LED_OFF;
	39	unsigned long delay = 0;
	40
fb31fbeb	41	if (unlikely(panic_heartbeats)) {
81fe8e5b	42	led_set_brightness_nosleep(led_cdev, LED_OFF);
fb31fbeb AH	43	return;
	44	}
	45
891c668b AN	46	/* acts like an actual heart beat -- ie thump-thump-pause... */
	47	switch (heartbeat_data->phase) {
	48	case 0:
	49	/*
	50	* The hyperbolic function below modifies the
	51	* heartbeat period length in dependency of the
	52	* current (1min) load. It goes through the points
	53	* f(0)=1260, f(1)=860, f(5)=510, f(inf)->300.
	54	*/
	55	heartbeat_data->period = 300 +
	56	(6720 << FSHIFT) / (5 * avenrun[0] + (7 << FSHIFT));
	57	heartbeat_data->period =
	58	msecs_to_jiffies(heartbeat_data->period);
	59	delay = msecs_to_jiffies(70);
	60	heartbeat_data->phase++;
1c7b9d0e JP	61	if (!heartbeat_data->invert)
1c7b9d0e JP	62	brightness = led_cdev->max_brightness;
891c668b AN	63	break;
	64	case 1:
	65	delay = heartbeat_data->period / 4 - msecs_to_jiffies(70);
	66	heartbeat_data->phase++;
1c7b9d0e JP	67	if (heartbeat_data->invert)
1c7b9d0e JP	68	brightness = led_cdev->max_brightness;
891c668b AN	69	break;
	70	case 2:
	71	delay = msecs_to_jiffies(70);
	72	heartbeat_data->phase++;
1c7b9d0e JP	73	if (!heartbeat_data->invert)
1c7b9d0e JP	74	brightness = led_cdev->max_brightness;
891c668b AN	75	break;
	76	default:
	77	delay = heartbeat_data->period - heartbeat_data->period / 4 -
	78	msecs_to_jiffies(70);
	79	heartbeat_data->phase = 0;
1c7b9d0e JP	80	if (heartbeat_data->invert)
1c7b9d0e JP	81	brightness = led_cdev->max_brightness;
891c668b AN	82	break;
	83	}
	84
81fe8e5b	85	led_set_brightness_nosleep(led_cdev, brightness);
891c668b AN	86	mod_timer(&heartbeat_data->timer, jiffies + delay);
	87	}
	88
1c7b9d0e JP	89	static ssize_t led_invert_show(struct device *dev,
	90	struct device_attribute attr, char buf)
	91	{
	92	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	93	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	94
	95	return sprintf(buf, "%u\n", heartbeat_data->invert);
	96	}
	97
	98	static ssize_t led_invert_store(struct device *dev,
	99	struct device_attribute attr, const char buf, size_t size)
	100	{
	101	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	102	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	103	unsigned long state;
	104	int ret;
	105
	106	ret = kstrtoul(buf, 0, &state);
	107	if (ret)
	108	return ret;
	109
	110	heartbeat_data->invert = !!state;
	111
	112	return size;
	113	}
	114
	115	static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store);
	116
891c668b AN	117	static void heartbeat_trig_activate(struct led_classdev *led_cdev)
	118	{
	119	struct heartbeat_trig_data *heartbeat_data;
1c7b9d0e	120	int rc;
891c668b AN	121
	122	heartbeat_data = kzalloc(sizeof(*heartbeat_data), GFP_KERNEL);
	123	if (!heartbeat_data)
	124	return;
	125
	126	led_cdev->trigger_data = heartbeat_data;
1c7b9d0e JP	127	rc = device_create_file(led_cdev->dev, &dev_attr_invert);
	128	if (rc) {
	129	kfree(led_cdev->trigger_data);
	130	return;
	131	}
	132
891c668b AN	133	setup_timer(&heartbeat_data->timer,
	134	led_heartbeat_function, (unsigned long) led_cdev);
	135	heartbeat_data->phase = 0;
	136	led_heartbeat_function(heartbeat_data->timer.data);
03c091e5	137	led_cdev->activated = true;
891c668b AN	138	}
	139
	140	static void heartbeat_trig_deactivate(struct led_classdev *led_cdev)
	141	{
	142	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	143
03c091e5	144	if (led_cdev->activated) {
891c668b	145	del_timer_sync(&heartbeat_data->timer);
1c7b9d0e	146	device_remove_file(led_cdev->dev, &dev_attr_invert);
891c668b	147	kfree(heartbeat_data);
03c091e5	148	led_cdev->activated = false;
891c668b AN	149	}
	150	}
	151
	152	static struct led_trigger heartbeat_led_trigger = {
	153	.name = "heartbeat",
	154	.activate = heartbeat_trig_activate,
	155	.deactivate = heartbeat_trig_deactivate,
	156	};
	157
5ab92a7c LW	158	static int heartbeat_pm_notifier(struct notifier_block *nb,
	159	unsigned long pm_event, void *unused)
	160	{
	161	int rc;
	162
	163	switch (pm_event) {
	164	case PM_SUSPEND_PREPARE:
	165	case PM_HIBERNATION_PREPARE:
	166	case PM_RESTORE_PREPARE:
	167	led_trigger_unregister(&heartbeat_led_trigger);
	168	break;
	169	case PM_POST_SUSPEND:
	170	case PM_POST_HIBERNATION:
	171	case PM_POST_RESTORE:
	172	rc = led_trigger_register(&heartbeat_led_trigger);
	173	if (rc)
	174	pr_err("could not re-register heartbeat trigger\n");
	175	break;
	176	default:
	177	break;
	178	}
	179	return NOTIFY_DONE;
	180	}
	181
49dca5ae AH	182	static int heartbeat_reboot_notifier(struct notifier_block *nb,
	183	unsigned long code, void *unused)
	184	{
	185	led_trigger_unregister(&heartbeat_led_trigger);
	186	return NOTIFY_DONE;
	187	}
	188
fb31fbeb AH	189	static int heartbeat_panic_notifier(struct notifier_block *nb,
	190	unsigned long code, void *unused)
	191	{
	192	panic_heartbeats = 1;
	193	return NOTIFY_DONE;
	194	}
	195
5ab92a7c LW	196	static struct notifier_block heartbeat_pm_nb = {
	197	.notifier_call = heartbeat_pm_notifier,
	198	};
	199
49dca5ae AH	200	static struct notifier_block heartbeat_reboot_nb = {
	201	.notifier_call = heartbeat_reboot_notifier,
	202	};
	203
	204	static struct notifier_block heartbeat_panic_nb = {
fb31fbeb	205	.notifier_call = heartbeat_panic_notifier,
49dca5ae AH	206	};
49dca5ae AH	207
891c668b AN	208	static int __init heartbeat_trig_init(void)
891c668b AN	209	{
49dca5ae AH	210	int rc = led_trigger_register(&heartbeat_led_trigger);
	211
	212	if (!rc) {
	213	atomic_notifier_chain_register(&panic_notifier_list,
	214	&heartbeat_panic_nb);
	215	register_reboot_notifier(&heartbeat_reboot_nb);
5ab92a7c	216	register_pm_notifier(&heartbeat_pm_nb);
49dca5ae AH	217	}
49dca5ae AH	218	return rc;
891c668b AN	219	}
	220
	221	static void __exit heartbeat_trig_exit(void)
	222	{
5ab92a7c	223	unregister_pm_notifier(&heartbeat_pm_nb);
49dca5ae AH	224	unregister_reboot_notifier(&heartbeat_reboot_nb);
	225	atomic_notifier_chain_unregister(&panic_notifier_list,
	226	&heartbeat_panic_nb);
891c668b AN	227	led_trigger_unregister(&heartbeat_led_trigger);
	228	}
	229
	230	module_init(heartbeat_trig_init);
	231	module_exit(heartbeat_trig_exit);
	232
	233	MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
	234	MODULE_DESCRIPTION("Heartbeat LED trigger");
	235	MODULE_LICENSE("GPL");