[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / leds / 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 "leds.h"

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

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;

	/* 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++;
		brightness = led_cdev->max_brightness;
		break;
	case 1:
		delay = heartbeat_data->period / 4 - msecs_to_jiffies(70);
		heartbeat_data->phase++;
		break;
	case 2:
		delay = msecs_to_jiffies(70);
		heartbeat_data->phase++;
		brightness = led_cdev->max_brightness;
		break;
	default:
		delay = heartbeat_data->period - heartbeat_data->period / 4 -
			msecs_to_jiffies(70);
		heartbeat_data->phase = 0;
		break;
	}

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

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

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

	led_cdev->trigger_data = heartbeat_data;
	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);
		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_reboot_notifier(struct notifier_block *nb,
				     unsigned long code, void *unused)
{
	led_trigger_unregister(&heartbeat_led_trigger);
	return NOTIFY_DONE;
}

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

static struct notifier_block heartbeat_panic_nb = {
	.notifier_call = heartbeat_reboot_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);
	}
	return rc;
}

static void __exit heartbeat_trig_exit(void)
{
	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>
891c668b AN	22	#include "leds.h"
	23
	24	struct heartbeat_trig_data {
	25	unsigned int phase;
	26	unsigned int period;
	27	struct timer_list timer;
	28	};
	29
	30	static void led_heartbeat_function(unsigned long data)
	31	{
	32	struct led_classdev led_cdev = (struct led_classdev ) data;
	33	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	34	unsigned long brightness = LED_OFF;
	35	unsigned long delay = 0;
	36
	37	/* acts like an actual heart beat -- ie thump-thump-pause... */
	38	switch (heartbeat_data->phase) {
	39	case 0:
	40	/*
	41	* The hyperbolic function below modifies the
	42	* heartbeat period length in dependency of the
	43	* current (1min) load. It goes through the points
	44	* f(0)=1260, f(1)=860, f(5)=510, f(inf)->300.
	45	*/
	46	heartbeat_data->period = 300 +
	47	(6720 << FSHIFT) / (5 * avenrun[0] + (7 << FSHIFT));
	48	heartbeat_data->period =
	49	msecs_to_jiffies(heartbeat_data->period);
	50	delay = msecs_to_jiffies(70);
	51	heartbeat_data->phase++;
1bd465e6	52	brightness = led_cdev->max_brightness;
891c668b AN	53	break;
	54	case 1:
	55	delay = heartbeat_data->period / 4 - msecs_to_jiffies(70);
	56	heartbeat_data->phase++;
	57	break;
	58	case 2:
	59	delay = msecs_to_jiffies(70);
	60	heartbeat_data->phase++;
1bd465e6	61	brightness = led_cdev->max_brightness;
891c668b AN	62	break;
	63	default:
	64	delay = heartbeat_data->period - heartbeat_data->period / 4 -
	65	msecs_to_jiffies(70);
	66	heartbeat_data->phase = 0;
	67	break;
	68	}
	69
	70	led_set_brightness(led_cdev, brightness);
	71	mod_timer(&heartbeat_data->timer, jiffies + delay);
	72	}
	73
	74	static void heartbeat_trig_activate(struct led_classdev *led_cdev)
	75	{
	76	struct heartbeat_trig_data *heartbeat_data;
	77
	78	heartbeat_data = kzalloc(sizeof(*heartbeat_data), GFP_KERNEL);
	79	if (!heartbeat_data)
	80	return;
	81
	82	led_cdev->trigger_data = heartbeat_data;
	83	setup_timer(&heartbeat_data->timer,
	84	led_heartbeat_function, (unsigned long) led_cdev);
	85	heartbeat_data->phase = 0;
	86	led_heartbeat_function(heartbeat_data->timer.data);
03c091e5	87	led_cdev->activated = true;
891c668b AN	88	}
	89
	90	static void heartbeat_trig_deactivate(struct led_classdev *led_cdev)
	91	{
	92	struct heartbeat_trig_data *heartbeat_data = led_cdev->trigger_data;
	93
03c091e5	94	if (led_cdev->activated) {
891c668b AN	95	del_timer_sync(&heartbeat_data->timer);
891c668b AN	96	kfree(heartbeat_data);
03c091e5	97	led_cdev->activated = false;
891c668b AN	98	}
	99	}
	100
	101	static struct led_trigger heartbeat_led_trigger = {
	102	.name = "heartbeat",
	103	.activate = heartbeat_trig_activate,
	104	.deactivate = heartbeat_trig_deactivate,
	105	};
	106
49dca5ae AH	107	static int heartbeat_reboot_notifier(struct notifier_block *nb,
	108	unsigned long code, void *unused)
	109	{
	110	led_trigger_unregister(&heartbeat_led_trigger);
	111	return NOTIFY_DONE;
	112	}
	113
	114	static struct notifier_block heartbeat_reboot_nb = {
	115	.notifier_call = heartbeat_reboot_notifier,
	116	};
	117
	118	static struct notifier_block heartbeat_panic_nb = {
	119	.notifier_call = heartbeat_reboot_notifier,
	120	};
	121
891c668b AN	122	static int __init heartbeat_trig_init(void)
891c668b AN	123	{
49dca5ae AH	124	int rc = led_trigger_register(&heartbeat_led_trigger);
	125
	126	if (!rc) {
	127	atomic_notifier_chain_register(&panic_notifier_list,
	128	&heartbeat_panic_nb);
	129	register_reboot_notifier(&heartbeat_reboot_nb);
	130	}
	131	return rc;
891c668b AN	132	}
	133
	134	static void __exit heartbeat_trig_exit(void)
	135	{
49dca5ae AH	136	unregister_reboot_notifier(&heartbeat_reboot_nb);
	137	atomic_notifier_chain_unregister(&panic_notifier_list,
	138	&heartbeat_panic_nb);
891c668b AN	139	led_trigger_unregister(&heartbeat_led_trigger);
	140	}
	141
	142	module_init(heartbeat_trig_init);
	143	module_exit(heartbeat_trig_exit);
	144
	145	MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
	146	MODULE_DESCRIPTION("Heartbeat LED trigger");
	147	MODULE_LICENSE("GPL");