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 */ 50 struct 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 60 extern void devfreq_monitor_start(struct devfreq *devfreq); 61 extern void devfreq_monitor_stop(struct devfreq *devfreq); 62 extern void devfreq_monitor_suspend(struct devfreq *devfreq); 63 extern void devfreq_monitor_resume(struct devfreq *devfreq); 64 extern void devfreq_interval_update(struct devfreq *devfreq, 65 unsigned int *delay); 66 67 extern int devfreq_add_governor(struct devfreq_governor *governor); 68 extern int devfreq_remove_governor(struct devfreq_governor *governor); 69 70 extern int devfreq_update_status(struct devfreq *devfreq, unsigned long freq); 71 72 static 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