[mirror_ubuntu-artful-kernel.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;
	}

	if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE, &led_cdev->work_flags))
		led_cdev->blink_brightness = led_cdev->new_blink_brightness;

	/* 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->blink_brightness;
		break;
	case 1:
		delay = heartbeat_data->period / 4 - msecs_to_jiffies(70);
		heartbeat_data->phase++;
		if (heartbeat_data->invert)
			brightness = led_cdev->blink_brightness;
		break;
	case 2:
		delay = msecs_to_jiffies(70);
		heartbeat_data->phase++;
		if (!heartbeat_data->invert)
			brightness = led_cdev->blink_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->blink_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;
	if (!led_cdev->blink_brightness)
		led_cdev->blink_brightness = led_cdev->max_brightness;
	led_heartbeat_function(heartbeat_data->timer.data);
	set_bit(LED_BLINK_SW, &led_cdev->work_flags);
	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);
		clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
		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
fb3d7691 JA	46	if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE, &led_cdev->work_flags))
	47	led_cdev->blink_brightness = led_cdev->new_blink_brightness;
	48
891c668b AN	49	/* acts like an actual heart beat -- ie thump-thump-pause... */
	50	switch (heartbeat_data->phase) {
	51	case 0:
	52	/*
	53	* The hyperbolic function below modifies the
	54	* heartbeat period length in dependency of the
	55	* current (1min) load. It goes through the points
	56	* f(0)=1260, f(1)=860, f(5)=510, f(inf)->300.
	57	*/
	58	heartbeat_data->period = 300 +
	59	(6720 << FSHIFT) / (5 * avenrun[0] + (7 << FSHIFT));
	60	heartbeat_data->period =
	61	msecs_to_jiffies(heartbeat_data->period);
	62	delay = msecs_to_jiffies(70);
	63	heartbeat_data->phase++;
1c7b9d0e	64	if (!heartbeat_data->invert)
fb3d7691	65	brightness = led_cdev->blink_brightness;
891c668b AN	66	break;
	67	case 1:
	68	delay = heartbeat_data->period / 4 - msecs_to_jiffies(70);
	69	heartbeat_data->phase++;
1c7b9d0e	70	if (heartbeat_data->invert)
fb3d7691	71	brightness = led_cdev->blink_brightness;
891c668b AN	72	break;
	73	case 2:
	74	delay = msecs_to_jiffies(70);
	75	heartbeat_data->phase++;
1c7b9d0e	76	if (!heartbeat_data->invert)
fb3d7691	77	brightness = led_cdev->blink_brightness;
891c668b AN	78	break;
	79	default:
	80	delay = heartbeat_data->period - heartbeat_data->period / 4 -
	81	msecs_to_jiffies(70);
	82	heartbeat_data->phase = 0;
1c7b9d0e	83	if (heartbeat_data->invert)
fb3d7691	84	brightness = led_cdev->blink_brightness;
891c668b AN	85	break;
	86	}
	87
81fe8e5b	88	led_set_brightness_nosleep(led_cdev, brightness);
891c668b AN	89	mod_timer(&heartbeat_data->timer, jiffies + delay);
	90	}
	91
1c7b9d0e JP	92	static ssize_t led_invert_show(struct device *dev,
	93	struct device_attribute attr, char buf)
	94	{
	95	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	96	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	97
	98	return sprintf(buf, "%u\n", heartbeat_data->invert);
	99	}
	100
	101	static ssize_t led_invert_store(struct device *dev,
	102	struct device_attribute attr, const char buf, size_t size)
	103	{
	104	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	105	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	106	unsigned long state;
	107	int ret;
	108
	109	ret = kstrtoul(buf, 0, &state);
	110	if (ret)
	111	return ret;
	112
	113	heartbeat_data->invert = !!state;
	114
	115	return size;
	116	}
	117
	118	static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store);
	119
891c668b AN	120	static void heartbeat_trig_activate(struct led_classdev *led_cdev)
	121	{
	122	struct heartbeat_trig_data *heartbeat_data;
1c7b9d0e	123	int rc;
891c668b AN	124
	125	heartbeat_data = kzalloc(sizeof(*heartbeat_data), GFP_KERNEL);
	126	if (!heartbeat_data)
	127	return;
	128
	129	led_cdev->trigger_data = heartbeat_data;
1c7b9d0e JP	130	rc = device_create_file(led_cdev->dev, &dev_attr_invert);
	131	if (rc) {
	132	kfree(led_cdev->trigger_data);
	133	return;
	134	}
	135
891c668b AN	136	setup_timer(&heartbeat_data->timer,
	137	led_heartbeat_function, (unsigned long) led_cdev);
	138	heartbeat_data->phase = 0;
fb3d7691 JA	139	if (!led_cdev->blink_brightness)
fb3d7691 JA	140	led_cdev->blink_brightness = led_cdev->max_brightness;
891c668b	141	led_heartbeat_function(heartbeat_data->timer.data);
fb3d7691	142	set_bit(LED_BLINK_SW, &led_cdev->work_flags);
03c091e5	143	led_cdev->activated = true;
891c668b AN	144	}
	145
	146	static void heartbeat_trig_deactivate(struct led_classdev *led_cdev)
	147	{
	148	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	149
03c091e5	150	if (led_cdev->activated) {
891c668b	151	del_timer_sync(&heartbeat_data->timer);
1c7b9d0e	152	device_remove_file(led_cdev->dev, &dev_attr_invert);
891c668b	153	kfree(heartbeat_data);
fb3d7691	154	clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
03c091e5	155	led_cdev->activated = false;
891c668b AN	156	}
	157	}
	158
	159	static struct led_trigger heartbeat_led_trigger = {
	160	.name = "heartbeat",
	161	.activate = heartbeat_trig_activate,
	162	.deactivate = heartbeat_trig_deactivate,
	163	};
	164
5ab92a7c LW	165	static int heartbeat_pm_notifier(struct notifier_block *nb,
	166	unsigned long pm_event, void *unused)
	167	{
	168	int rc;
	169
	170	switch (pm_event) {
	171	case PM_SUSPEND_PREPARE:
	172	case PM_HIBERNATION_PREPARE:
	173	case PM_RESTORE_PREPARE:
	174	led_trigger_unregister(&heartbeat_led_trigger);
	175	break;
	176	case PM_POST_SUSPEND:
	177	case PM_POST_HIBERNATION:
	178	case PM_POST_RESTORE:
	179	rc = led_trigger_register(&heartbeat_led_trigger);
	180	if (rc)
	181	pr_err("could not re-register heartbeat trigger\n");
	182	break;
	183	default:
	184	break;
	185	}
	186	return NOTIFY_DONE;
	187	}
	188
49dca5ae AH	189	static int heartbeat_reboot_notifier(struct notifier_block *nb,
	190	unsigned long code, void *unused)
	191	{
	192	led_trigger_unregister(&heartbeat_led_trigger);
	193	return NOTIFY_DONE;
	194	}
	195
fb31fbeb AH	196	static int heartbeat_panic_notifier(struct notifier_block *nb,
	197	unsigned long code, void *unused)
	198	{
	199	panic_heartbeats = 1;
	200	return NOTIFY_DONE;
	201	}
	202
5ab92a7c LW	203	static struct notifier_block heartbeat_pm_nb = {
	204	.notifier_call = heartbeat_pm_notifier,
	205	};
	206
49dca5ae AH	207	static struct notifier_block heartbeat_reboot_nb = {
	208	.notifier_call = heartbeat_reboot_notifier,
	209	};
	210
	211	static struct notifier_block heartbeat_panic_nb = {
fb31fbeb	212	.notifier_call = heartbeat_panic_notifier,
49dca5ae AH	213	};
49dca5ae AH	214
891c668b AN	215	static int __init heartbeat_trig_init(void)
891c668b AN	216	{
49dca5ae AH	217	int rc = led_trigger_register(&heartbeat_led_trigger);
	218
	219	if (!rc) {
	220	atomic_notifier_chain_register(&panic_notifier_list,
	221	&heartbeat_panic_nb);
	222	register_reboot_notifier(&heartbeat_reboot_nb);
5ab92a7c	223	register_pm_notifier(&heartbeat_pm_nb);
49dca5ae AH	224	}
49dca5ae AH	225	return rc;
891c668b AN	226	}
	227
	228	static void __exit heartbeat_trig_exit(void)
	229	{
5ab92a7c	230	unregister_pm_notifier(&heartbeat_pm_nb);
49dca5ae AH	231	unregister_reboot_notifier(&heartbeat_reboot_nb);
	232	atomic_notifier_chain_unregister(&panic_notifier_list,
	233	&heartbeat_panic_nb);
891c668b AN	234	led_trigger_unregister(&heartbeat_led_trigger);
	235	}
	236
	237	module_init(heartbeat_trig_init);
	238	module_exit(heartbeat_trig_exit);
	239
	240	MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
	241	MODULE_DESCRIPTION("Heartbeat LED trigger");
	242	MODULE_LICENSE("GPL");