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 struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
152 struct device *dev, int index)
153{
154 return ERR_PTR(-EINVAL);
155}
156
157static inline int devfreq_event_get_edev_count(struct device *dev)
158{
159 return -EINVAL;
160}
161
162static inline struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
163 struct devfreq_event_desc *desc)
164{
165 return ERR_PTR(-EINVAL);
166}
167
168static inline int devfreq_event_remove_edev(struct devfreq_event_dev *edev)
169{
170 return -EINVAL;
171}
172
173static inline struct devfreq_event_dev *devm_devfreq_event_add_edev(
174 struct device *dev,
175 struct devfreq_event_desc *desc)
176{
177 return ERR_PTR(-EINVAL);
178}
179
180static inline void devm_devfreq_event_remove_edev(struct device *dev,
181 struct devfreq_event_dev *edev)
182{
183}
184
185static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
186{
187 return NULL;
188}
189#endif /* CONFIG_PM_DEVFREQ_EVENT */
190
191#endif /* __LINUX_DEVFREQ_EVENT_H__ */
192