governor_powersave.c
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/*
* linux/drivers/devfreq/governor_powersave.c
*
* Copyright (C) 2011 Samsung Electronics
* MyungJoo Ham <myungjoo.ham@samsung.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/devfreq.h>
#include <linux/module.h>
#include "governor.h"
static int devfreq_powersave_func(struct devfreq *df,
unsigned long *freq)
{
/*
* target callback should be able to get ceiling value as
* said in devfreq.h
*/
*freq = df->min_freq;
return 0;
}
static int devfreq_powersave_handler(struct devfreq *devfreq,
unsigned int event, void *data)
{
int ret = 0;
if (event == DEVFREQ_GOV_START) {
mutex_lock(&devfreq->lock);
ret = update_devfreq(devfreq);
mutex_unlock(&devfreq->lock);
}
return ret;
}
static struct devfreq_governor devfreq_powersave = {
.name = "powersave",
.get_target_freq = devfreq_powersave_func,
.event_handler = devfreq_powersave_handler,
};
static int __init devfreq_powersave_init(void)
{
return devfreq_add_governor(&devfreq_powersave);
}
subsys_initcall(devfreq_powersave_init);
static void __exit devfreq_powersave_exit(void)
{
int ret;
ret = devfreq_remove_governor(&devfreq_powersave);
if (ret)
pr_err("%s: failed remove governor %d\n", __func__, ret);
return;
}
module_exit(devfreq_powersave_exit);
MODULE_LICENSE("GPL");