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/**
29 * struct devfreq_governor - Devfreq policy governor
30 * @node:		list node - contains registered devfreq governors
31 * @name:		Governor's name
32 * @immutable:		Immutable flag for governor. If the value is 1,
33 *			this govenror is never changeable to other governor.
34 * @get_target_freq:	Returns desired operating frequency for the device.
35 *			Basically, get_target_freq will run
36 *			devfreq_dev_profile.get_dev_status() to get the
37 *			status of the device (load = busy_time / total_time).
38 *			If no_central_polling is set, this callback is called
39 *			only with update_devfreq() notified by OPP.
40 * @event_handler:      Callback for devfreq core framework to notify events
41 *                      to governors. Events include per device governor
42 *                      init and exit, opp changes out of devfreq, suspend
43 *                      and resume of per device devfreq during device idle.
44 *
45 * Note that the callbacks are called with devfreq->lock locked by devfreq.
46 */
47struct devfreq_governor {
48	struct list_head node;
49
50	const char name[DEVFREQ_NAME_LEN];
51	const unsigned int immutable;
52	int (*get_target_freq)(struct devfreq *this, unsigned long *freq);
53	int (*event_handler)(struct devfreq *devfreq,
54				unsigned int event, void *data);
55};
56
57/* Caution: devfreq->lock must be locked before calling update_devfreq */
58extern int update_devfreq(struct devfreq *devfreq);
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 */