xref: /linux-6.15/include/linux/devfreq-event.h (revision bb4e9af0)
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 <[email protected]>
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__ */
189