1/*
2 * governor.h - internal header for devfreq governors.
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 * This header is for devfreq governors in drivers/devfreq/
12 */
13
14#ifndef _GOVERNOR_H
15#define _GOVERNOR_H
16
17#include <linux/devfreq.h>
18
19#define to_devfreq(DEV) container_of((DEV), struct devfreq, dev)
20
21/* Devfreq events */
22#define DEVFREQ_GOV_START 0x1
23#define DEVFREQ_GOV_STOP 0x2
24#define DEVFREQ_GOV_INTERVAL 0x3
25#define DEVFREQ_GOV_SUSPEND 0x4
26#define DEVFREQ_GOV_RESUME 0x5
27
28#define DEVFREQ_MIN_FREQ 0
29#define DEVFREQ_MAX_FREQ ULONG_MAX
30
31/**
32 * struct devfreq_governor - Devfreq policy governor
33 * @node: list node - contains registered devfreq governors
34 * @name: Governor's name
35 * @immutable: Immutable flag for governor. If the value is 1,
36 * this govenror is never changeable to other governor.
37 * @get_target_freq: Returns desired operating frequency for the device.
38 * Basically, get_target_freq will run
39 * devfreq_dev_profile.get_dev_status() to get the
40 * status of the device (load = busy_time / total_time).
41 * If no_central_polling is set, this callback is called
42 * only with update_devfreq() notified by OPP.
43 * @event_handler: Callback for devfreq core framework to notify events
44 * to governors. Events include per device governor
45 * init and exit, opp changes out of devfreq, suspend
46 * and resume of per device devfreq during device idle.
47 *
48 * Note that the callbacks are called with devfreq->lock locked by devfreq.
49 */
50struct devfreq_governor {
51 struct list_head node;
52
53 const char name[DEVFREQ_NAME_LEN];
54 const unsigned int immutable;
55 int (*get_target_freq)(struct devfreq *this, unsigned long *freq);
56 int (*event_handler)(struct devfreq *devfreq,
57 unsigned int event, void *data);
58};
59
60extern void devfreq_monitor_start(struct devfreq *devfreq);
61extern void devfreq_monitor_stop(struct devfreq *devfreq);
62extern void devfreq_monitor_suspend(struct devfreq *devfreq);
63extern void devfreq_monitor_resume(struct devfreq *devfreq);
64extern void devfreq_interval_update(struct devfreq *devfreq,
65 unsigned int *delay);
66
67extern int devfreq_add_governor(struct devfreq_governor *governor);
68extern int devfreq_remove_governor(struct devfreq_governor *governor);
69
70extern int devfreq_update_status(struct devfreq *devfreq, unsigned long freq);
71
72static inline int devfreq_update_stats(struct devfreq *df)
73{
74 return df->profile->get_dev_status(df->dev.parent, &df->last_status);
75}
76#endif /* _GOVERNOR_H */
77