include/linux/devfreq-event.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * devfreq-event: a framework to provide raw data and events of devfreq devices
   4  *
   5  * Copyright (C) 2014 Samsung Electronics
   6  * Author: Chanwoo Choi <cw00.choi@samsung.com>
   7  */
   8
   9 #ifndef __LINUX_DEVFREQ_EVENT_H__
  10 #define __LINUX_DEVFREQ_EVENT_H__
  11
  12 #include <linux/device.h>
  13
  14 /**
  15  * struct devfreq_event_dev - the devfreq-event device
  16  *
  17  * @node        : Contain the devfreq-event device that have been registered.
  18  * @dev         : the device registered by devfreq-event class. dev.parent is
  19  *                the device using devfreq-event.
  20  * @lock        : a mutex to protect accessing devfreq-event.
  21  * @enable_count: the number of enable function have been called.
  22  * @desc        : the description for devfreq-event device.
  23  *
  24  * This structure contains devfreq-event device information.
  25  */
  26 struct devfreq_event_dev {
  27         struct list_head node;
  28
  29         struct device dev;
  30         struct mutex lock;
  31         u32 enable_count;
  32
  33         const struct devfreq_event_desc *desc;
  34 };
  35
  36 /**
  37  * struct devfreq_event_data - the devfreq-event data
  38  *
  39  * @load_count  : load count of devfreq-event device for the given period.
  40  * @total_count : total count of devfreq-event device for the given period.
  41  *                each count may represent a clock cycle, a time unit
  42  *                (ns/us/...), or anything the device driver wants.
  43  *                Generally, utilization is load_count / total_count.
  44  *
  45  * This structure contains the data of devfreq-event device for polling period.
  46  */
  47 struct devfreq_event_data {
  48         unsigned long load_count;
  49         unsigned long total_count;
  50 };
  51
  52 /**
  53  * struct devfreq_event_ops - the operations of devfreq-event device
  54  *
  55  * @enable      : Enable the devfreq-event device.
  56  * @disable     : Disable the devfreq-event device.
  57  * @reset       : Reset all setting of the devfreq-event device.
  58  * @set_event   : Set the specific event type for the devfreq-event device.
  59  * @get_event   : Get the result of the devfreq-event devie with specific
  60  *                event type.
  61  *
  62  * This structure contains devfreq-event device operations which can be
  63  * implemented by devfreq-event device drivers.
  64  */
  65 struct devfreq_event_ops {
  66         /* Optional functions */
  67         int (*enable)(struct devfreq_event_dev *edev);
  68         int (*disable)(struct devfreq_event_dev *edev);
  69         int (*reset)(struct devfreq_event_dev *edev);
  70
  71         /* Mandatory functions */
  72         int (*set_event)(struct devfreq_event_dev *edev);
  73         int (*get_event)(struct devfreq_event_dev *edev,
  74                          struct devfreq_event_data *edata);
  75 };
  76
  77 /**
  78  * struct devfreq_event_desc - the descriptor of devfreq-event device
  79  *
  80  * @name        : the name of devfreq-event device.
  81  * @driver_data : the private data for devfreq-event driver.
  82  * @ops         : the operation to control devfreq-event device.
  83  *
  84  * Each devfreq-event device is described with a this structure.
  85  * This structure contains the various data for devfreq-event device.
  86  */
  87 struct devfreq_event_desc {
  88         const char *name;
  89         void *driver_data;
  90
  91         const struct devfreq_event_ops *ops;
  92 };
  93
  94 #if defined(CONFIG_PM_DEVFREQ_EVENT)
  95 extern int devfreq_event_enable_edev(struct devfreq_event_dev *edev);
  96 extern int devfreq_event_disable_edev(struct devfreq_event_dev *edev);
  97 extern bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
  98 extern int devfreq_event_set_event(struct devfreq_event_dev *edev);
  99 extern int devfreq_event_get_event(struct devfreq_event_dev *edev,
 100                                 struct devfreq_event_data *edata);
 101 extern int devfreq_event_reset_event(struct devfreq_event_dev *edev);
 102 extern struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
 103                                 struct device *dev, int index);
 104 extern int devfreq_event_get_edev_count(struct device *dev);
 105 extern struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
 106                                 struct devfreq_event_desc *desc);
 107 extern int devfreq_event_remove_edev(struct devfreq_event_dev *edev);
 108 extern struct devfreq_event_dev *devm_devfreq_event_add_edev(struct device *dev,
 109                                 struct devfreq_event_desc *desc);
 110 extern void devm_devfreq_event_remove_edev(struct device *dev,
 111                                 struct devfreq_event_dev *edev);
 112 static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
 113 {
 114         return edev->desc->driver_data;
 115 }
 116 #else
 117 static inline int devfreq_event_enable_edev(struct devfreq_event_dev *edev)
 118 {
 119         return -EINVAL;
 120 }
 121
 122 static inline int devfreq_event_disable_edev(struct devfreq_event_dev *edev)
 123 {
 124         return -EINVAL;
 125 }
 126
 127 static inline bool devfreq_event_is_enabled(struct devfreq_event_dev *edev)
 128 {
 129         return false;
 130 }
 131
 132 static inline int devfreq_event_set_event(struct devfreq_event_dev *edev)
 133 {
 134         return -EINVAL;
 135 }
 136
 137 static inline int devfreq_event_get_event(struct devfreq_event_dev *edev,
 138                                         struct devfreq_event_data *edata)
 139 {
 140         return -EINVAL;
 141 }
 142
 143 static inline int devfreq_event_reset_event(struct devfreq_event_dev *edev)
 144 {
 145         return -EINVAL;
 146 }
 147
 148 static inline struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
 149                                         struct device *dev, int index)
 150 {
 151         return ERR_PTR(-EINVAL);
 152 }
 153
 154 static inline int devfreq_event_get_edev_count(struct device *dev)
 155 {
 156         return -EINVAL;
 157 }
 158
 159 static inline struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
 160                                         struct devfreq_event_desc *desc)
 161 {
 162         return ERR_PTR(-EINVAL);
 163 }
 164
 165 static inline int devfreq_event_remove_edev(struct devfreq_event_dev *edev)
 166 {
 167         return -EINVAL;
 168 }
 169
 170 static inline struct devfreq_event_dev *devm_devfreq_event_add_edev(
 171                                         struct device *dev,
 172                                         struct devfreq_event_desc *desc)
 173 {
 174         return ERR_PTR(-EINVAL);
 175 }
 176
 177 static inline void devm_devfreq_event_remove_edev(struct device *dev,
 178                                         struct devfreq_event_dev *edev)
 179 {
 180 }
 181
 182 static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
 183 {
 184         return NULL;
 185 }
 186 #endif /* CONFIG_PM_DEVFREQ_EVENT */
 187
 188 #endif /* __LINUX_DEVFREQ_EVENT_H__ */