GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / devfreq / governor_performance.c
1 /*
2  *  linux/drivers/devfreq/governor_performance.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
16 static int devfreq_performance_func(struct devfreq *df,
17                                     unsigned long *freq)
18 {
19         /*
20          * target callback should be able to get floor value as
21          * said in devfreq.h
22          */
23         if (!df->max_freq)
24                 *freq = UINT_MAX;
25         else
26                 *freq = df->max_freq;
27         return 0;
28 }
29
30 static int devfreq_performance_handler(struct devfreq *devfreq,
31                                 unsigned int event, void *data)
32 {
33         int ret = 0;
34
35         if (event == DEVFREQ_GOV_START) {
36                 mutex_lock(&devfreq->lock);
37                 ret = update_devfreq(devfreq);
38                 mutex_unlock(&devfreq->lock);
39         }
40
41         return ret;
42 }
43
44 static struct devfreq_governor devfreq_performance = {
45         .name = "performance",
46         .get_target_freq = devfreq_performance_func,
47         .event_handler = devfreq_performance_handler,
48 };
49
50 static int __init devfreq_performance_init(void)
51 {
52         return devfreq_add_governor(&devfreq_performance);
53 }
54 subsys_initcall(devfreq_performance_init);
55
56 static void __exit devfreq_performance_exit(void)
57 {
58         int ret;
59
60         ret = devfreq_remove_governor(&devfreq_performance);
61         if (ret)
62                 pr_err("%s: failed remove governor %d\n", __func__, ret);
63
64         return;
65 }
66 module_exit(devfreq_performance_exit);
67 MODULE_LICENSE("GPL");