linux/drivers/devfreq/governor.h

77 lines
2.8 KiB
C

/*
* governor.h - internal header for devfreq governors.
*
* 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.
*
* This header is for devfreq governors in drivers/devfreq/
*/
#ifndef _GOVERNOR_H
#define _GOVERNOR_H
#include <linux/devfreq.h>
#define to_devfreq(DEV) container_of((DEV), struct devfreq, dev)
/* Devfreq events */
#define DEVFREQ_GOV_START 0x1
#define DEVFREQ_GOV_STOP 0x2
#define DEVFREQ_GOV_INTERVAL 0x3
#define DEVFREQ_GOV_SUSPEND 0x4
#define DEVFREQ_GOV_RESUME 0x5
/**
* struct devfreq_governor - Devfreq policy governor
* @node: list node - contains registered devfreq governors
* @name: Governor's name
* @immutable: Immutable flag for governor. If the value is 1,
* this govenror is never changeable to other governor.
* @get_target_freq: Returns desired operating frequency for the device.
* Basically, get_target_freq will run
* devfreq_dev_profile.get_dev_status() to get the
* status of the device (load = busy_time / total_time).
* If no_central_polling is set, this callback is called
* only with update_devfreq() notified by OPP.
* @event_handler: Callback for devfreq core framework to notify events
* to governors. Events include per device governor
* init and exit, opp changes out of devfreq, suspend
* and resume of per device devfreq during device idle.
*
* Note that the callbacks are called with devfreq->lock locked by devfreq.
*/
struct devfreq_governor {
struct list_head node;
const char name[DEVFREQ_NAME_LEN];
const unsigned int immutable;
int (*get_target_freq)(struct devfreq *this, unsigned long *freq);
int (*event_handler)(struct devfreq *devfreq,
unsigned int event, void *data);
};
/* Caution: devfreq->lock must be locked before calling update_devfreq */
extern int update_devfreq(struct devfreq *devfreq);
extern void devfreq_monitor_start(struct devfreq *devfreq);
extern void devfreq_monitor_stop(struct devfreq *devfreq);
extern void devfreq_monitor_suspend(struct devfreq *devfreq);
extern void devfreq_monitor_resume(struct devfreq *devfreq);
extern void devfreq_interval_update(struct devfreq *devfreq,
unsigned int *delay);
extern int devfreq_add_governor(struct devfreq_governor *governor);
extern int devfreq_remove_governor(struct devfreq_governor *governor);
extern int devfreq_update_status(struct devfreq *devfreq, unsigned long freq);
static inline int devfreq_update_stats(struct devfreq *df)
{
return df->profile->get_dev_status(df->dev.parent, &df->last_status);
}
#endif /* _GOVERNOR_H */