1/*
2 *  linux/drivers/devfreq/governor_powersave.c
3 *
4 *  Copyright (C) 2011 Samsung Electronics
5 *	MyungJoo Ham <myungjoo.ham@samsung.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/devfreq.h>
13#include <linux/module.h>
14#include "governor.h"
15
16static int devfreq_powersave_func(struct devfreq *df,
17				  unsigned long *freq)
18{
19	/*
20	 * target callback should be able to get ceiling value as
21	 * said in devfreq.h
22	 */
23	*freq = df->min_freq;
24	return 0;
25}
26
27static int devfreq_powersave_handler(struct devfreq *devfreq,
28				unsigned int event, void *data)
29{
30	int ret = 0;
31
32	if (event == DEVFREQ_GOV_START) {
33		mutex_lock(&devfreq->lock);
34		ret = update_devfreq(devfreq);
35		mutex_unlock(&devfreq->lock);
36	}
37
38	return ret;
39}
40
41static struct devfreq_governor devfreq_powersave = {
42	.name = "powersave",
43	.get_target_freq = devfreq_powersave_func,
44	.event_handler = devfreq_powersave_handler,
45};
46
47static int __init devfreq_powersave_init(void)
48{
49	return devfreq_add_governor(&devfreq_powersave);
50}
51subsys_initcall(devfreq_powersave_init);
52
53static void __exit devfreq_powersave_exit(void)
54{
55	int ret;
56
57	ret = devfreq_remove_governor(&devfreq_powersave);
58	if (ret)
59		pr_err("%s: failed remove governor %d\n", __func__, ret);
60
61	return;
62}
63module_exit(devfreq_powersave_exit);
64MODULE_LICENSE("GPL");
65