LXR linux/include/linux/devfreq-event.h

   1/*
   2 * devfreq-event: a framework to provide raw data and events of devfreq devices
   3 *
   4 * Copyright (C) 2014 Samsung Electronics
   5 * Author: Chanwoo Choi <cw00.choi@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
  12#ifndef __LINUX_DEVFREQ_EVENT_H__
  13#define __LINUX_DEVFREQ_EVENT_H__
  14
  15#include <linux/device.h>
  16
  17/**
  18 * struct devfreq_event_dev - the devfreq-event device
  19 *
  20 * @node        : Contain the devfreq-event device that have been registered.
  21 * @dev         : the device registered by devfreq-event class. dev.parent is
  22 *                the device using devfreq-event.
  23 * @lock        : a mutex to protect accessing devfreq-event.
  24 * @enable_count: the number of enable function have been called.
  25 * @desc        : the description for devfreq-event device.
  26 *
  27 * This structure contains devfreq-event device information.
  28 */
  29struct devfreq_event_dev {
  30        struct list_head node;
  31
  32        struct device dev;
  33        struct mutex lock;
  34        u32 enable_count;
  35
  36        const struct devfreq_event_desc *desc;
  37};
  38
  39/**
  40 * struct devfreq_event_data - the devfreq-event data
  41 *
  42 * @load_count  : load count of devfreq-event device for the given period.
  43 * @total_count : total count of devfreq-event device for the given period.
  44 *                each count may represent a clock cycle, a time unit
  45 *                (ns/us/...), or anything the device driver wants.
  46 *                Generally, utilization is load_count / total_count.
  47 *
  48 * This structure contains the data of devfreq-event device for polling period.
  49 */
  50struct devfreq_event_data {
  51        unsigned long load_count;
  52        unsigned long total_count;
  53};
  54
  55/**
  56 * struct devfreq_event_ops - the operations of devfreq-event device
  57 *
  58 * @enable      : Enable the devfreq-event device.
  59 * @disable     : Disable the devfreq-event device.
  60 * @reset       : Reset all setting of the devfreq-event device.
  61 * @set_event   : Set the specific event type for the devfreq-event device.
  62 * @get_event   : Get the result of the devfreq-event devie with specific
  63 *                event type.
  64 *
  65 * This structure contains devfreq-event device operations which can be
  66 * implemented by devfreq-event device drivers.
  67 */
  68struct devfreq_event_ops {
  69        /* Optional functions */
  70        int (*enable)(struct devfreq_event_dev *edev);
  71        int (*disable)(struct devfreq_event_dev *edev);
  72        int (*reset)(struct devfreq_event_dev *edev);
  73
  74        /* Mandatory functions */
  75        int (*set_event)(struct devfreq_event_dev *edev);
  76        int (*get_event)(struct devfreq_event_dev *edev,
  77                         struct devfreq_event_data *edata);
  78};
  79
  80/**
  81 * struct devfreq_event_desc - the descriptor of devfreq-event device
  82 *
  83 * @name        : the name of devfreq-event device.
  84 * @driver_data : the private data for devfreq-event driver.
  85 * @ops         : the operation to control devfreq-event device.
  86 *
  87 * Each devfreq-event device is described with a this structure.
  88 * This structure contains the various data for devfreq-event device.
  89 */
  90struct devfreq_event_desc {
  91        const char *name;
  92        void *driver_data;
  93
  94        const struct devfreq_event_ops *ops;
  95};
  96
  97#if defined(CONFIG_PM_DEVFREQ_EVENT)
  98extern int devfreq_event_enable_edev(struct devfreq_event_dev *edev);
  99extern int devfreq_event_disable_edev(struct devfreq_event_dev *edev);
 100extern bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
 101extern int devfreq_event_set_event(struct devfreq_event_dev *edev);
 102extern int devfreq_event_get_event(struct devfreq_event_dev *edev,
 103                                struct devfreq_event_data *edata);
 104extern int devfreq_event_reset_event(struct devfreq_event_dev *edev);
 105extern struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
 106                                struct device *dev, int index);
 107extern int devfreq_event_get_edev_count(struct device *dev);
 108extern struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
 109                                struct devfreq_event_desc *desc);
 110extern int devfreq_event_remove_edev(struct devfreq_event_dev *edev);
 111extern struct devfreq_event_dev *devm_devfreq_event_add_edev(struct device *dev,
 112                                struct devfreq_event_desc *desc);
 113extern void devm_devfreq_event_remove_edev(struct device *dev,
 114                                struct devfreq_event_dev *edev);
 115static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
 116{
 117        return edev->desc->driver_data;
 118}
 119#else
 120static inline int devfreq_event_enable_edev(struct devfreq_event_dev *edev)
 121{
 122        return -EINVAL;
 123}
 124
 125static inline int devfreq_event_disable_edev(struct devfreq_event_dev *edev)
 126{
 127        return -EINVAL;
 128}
 129
 130static inline bool devfreq_event_is_enabled(struct devfreq_event_dev *edev)
 131{
 132        return false;
 133}
 134
 135static inline int devfreq_event_set_event(struct devfreq_event_dev *edev)
 136{
 137        return -EINVAL;
 138}
 139
 140static inline int devfreq_event_get_event(struct devfreq_event_dev *edev,
 141                                        struct devfreq_event_data *edata)
 142{
 143        return -EINVAL;
 144}
 145
 146static inline int devfreq_event_reset_event(struct devfreq_event_dev *edev)
 147{
 148        return -EINVAL;
 149}
 150
 151static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
 152{
 153        return ERR_PTR(-EINVAL);
 154}
 155
 156static inline struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
 157                                        struct device *dev, int index)
 158{
 159        return ERR_PTR(-EINVAL);
 160}
 161
 162static inline int devfreq_event_get_edev_count(struct device *dev)
 163{
 164        return -EINVAL;
 165}
 166
 167static inline struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
 168                                        struct devfreq_event_desc *desc)
 169{
 170        return ERR_PTR(-EINVAL);
 171}
 172
 173static inline int devfreq_event_remove_edev(struct devfreq_event_dev *edev)
 174{
 175        return -EINVAL;
 176}
 177
 178static inline struct devfreq_event_dev *devm_devfreq_event_add_edev(
 179                                        struct device *dev,
 180                                        struct devfreq_event_desc *desc)
 181{
 182        return ERR_PTR(-EINVAL);
 183}
 184
 185static inline void devm_devfreq_event_remove_edev(struct device *dev,
 186                                        struct devfreq_event_dev *edev)
 187{
 188}
 189
 190static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
 191{
 192        return NULL;
 193}
 194#endif /* CONFIG_PM_DEVFREQ_EVENT */
 195
 196#endif /* __LINUX_DEVFREQ_EVENT_H__ */
 197