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 * @event_type : the type of the event determined and used by driver
82 * @driver_data : the private data for devfreq-event driver.
83 * @ops : the operation to control devfreq-event device.
84 *
85 * Each devfreq-event device is described with a this structure.
86 * This structure contains the various data for devfreq-event device.
87 * The event_type describes what is going to be counted in the register.
88 * It might choose to count e.g. read requests, write data in bytes, etc.
89 * The full supported list of types is present in specyfic header in:
90 * include/dt-bindings/pmu/.
91 */
92 struct devfreq_event_desc {
93 const char *name;
94 u32 event_type;
95 void *driver_data;
96
97 const struct devfreq_event_ops *ops;
98 };
99
100 #if defined(CONFIG_PM_DEVFREQ_EVENT)
101 extern int devfreq_event_enable_edev(struct devfreq_event_dev *edev);
102 extern int devfreq_event_disable_edev(struct devfreq_event_dev *edev);
103 extern bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
104 extern int devfreq_event_set_event(struct devfreq_event_dev *edev);
105 extern int devfreq_event_get_event(struct devfreq_event_dev *edev,
106 struct devfreq_event_data *edata);
107 extern int devfreq_event_reset_event(struct devfreq_event_dev *edev);
108 extern struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
109 struct device *dev,
110 const char *phandle_name,
111 int index);
112 extern int devfreq_event_get_edev_count(struct device *dev,
113 const char *phandle_name);
114 extern struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
115 struct devfreq_event_desc *desc);
116 extern int devfreq_event_remove_edev(struct devfreq_event_dev *edev);
117 extern struct devfreq_event_dev *devm_devfreq_event_add_edev(struct device *dev,
118 struct devfreq_event_desc *desc);
119 extern void devm_devfreq_event_remove_edev(struct device *dev,
120 struct devfreq_event_dev *edev);
121 static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
122 {
123 return edev->desc->driver_data;
124 }
125 #else
126 static inline int devfreq_event_enable_edev(struct devfreq_event_dev *edev)
127 {
128 return -EINVAL;
129 }
130
131 static inline int devfreq_event_disable_edev(struct devfreq_event_dev *edev)
132 {
133 return -EINVAL;
134 }
135
136 static inline bool devfreq_event_is_enabled(struct devfreq_event_dev *edev)
137 {
138 return false;
139 }
140
141 static inline int devfreq_event_set_event(struct devfreq_event_dev *edev)
142 {
143 return -EINVAL;
144 }
145
146 static inline int devfreq_event_get_event(struct devfreq_event_dev *edev,
147 struct devfreq_event_data *edata)
148 {
149 return -EINVAL;
150 }
151
152 static inline int devfreq_event_reset_event(struct devfreq_event_dev *edev)
153 {
154 return -EINVAL;
155 }
156
157 static inline struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
158 struct device *dev,
159 const char *phandle_name,
160 int index)
161 {
162 return ERR_PTR(-EINVAL);
163 }
164
165 static inline int devfreq_event_get_edev_count(struct device *dev,
166 const char *phandle_name)
167 {
168 return -EINVAL;
169 }
170
171 static inline struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
172 struct devfreq_event_desc *desc)
173 {
174 return ERR_PTR(-EINVAL);
175 }
176
177 static inline int devfreq_event_remove_edev(struct devfreq_event_dev *edev)
178 {
179 return -EINVAL;
180 }
181
182 static inline struct devfreq_event_dev *devm_devfreq_event_add_edev(
183 struct device *dev,
184 struct devfreq_event_desc *desc)
185 {
186 return ERR_PTR(-EINVAL);
187 }
188
189 static inline void devm_devfreq_event_remove_edev(struct device *dev,
190 struct devfreq_event_dev *edev)
191 {
192 }
193
194 static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
195 {
196 return NULL;
197 }
198 #endif /* CONFIG_PM_DEVFREQ_EVENT */
199
200 #endif /* __LINUX_DEVFREQ_EVENT_H__ */
201
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