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 */ 47 struct 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 */ 58 extern int update_devfreq(struct devfreq *devfreq); 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 #endif /* _GOVERNOR_H */ 73