1 /*
2 * V4L2 clock service
3 *
4 * Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * ATTENTION: This is a temporary API and it shall be replaced by the generic
11 * clock API, when the latter becomes widely available.
12 */
13
14 #ifndef MEDIA_V4L2_CLK_H
15 #define MEDIA_V4L2_CLK_H
16
17 #include <linux/atomic.h>
18 #include <linux/export.h>
19 #include <linux/list.h>
20 #include <linux/mutex.h>
21
22 struct module;
23 struct device;
24
25 struct clk;
26 struct v4l2_clk {
27 struct list_head list;
28 const struct v4l2_clk_ops *ops;
29 const char *dev_id;
30 int enable;
31 struct mutex lock; /* Protect the enable count */
32 atomic_t use_count;
33 struct clk *clk;
34 void *priv;
35 };
36
37 struct v4l2_clk_ops {
38 struct module *owner;
39 int (*enable)(struct v4l2_clk *clk);
40 void (*disable)(struct v4l2_clk *clk);
41 unsigned long (*get_rate)(struct v4l2_clk *clk);
42 int (*set_rate)(struct v4l2_clk *clk, unsigned long);
43 };
44
45 struct v4l2_clk *v4l2_clk_register(const struct v4l2_clk_ops *ops,
46 const char *dev_name,
47 void *priv);
48 void v4l2_clk_unregister(struct v4l2_clk *clk);
49 struct v4l2_clk *v4l2_clk_get(struct device *dev, const char *id);
50 void v4l2_clk_put(struct v4l2_clk *clk);
51 int v4l2_clk_enable(struct v4l2_clk *clk);
52 void v4l2_clk_disable(struct v4l2_clk *clk);
53 unsigned long v4l2_clk_get_rate(struct v4l2_clk *clk);
54 int v4l2_clk_set_rate(struct v4l2_clk *clk, unsigned long rate);
55
56 struct module;
57
58 struct v4l2_clk *__v4l2_clk_register_fixed(const char *dev_id,
59 unsigned long rate, struct module *owner);
60 void v4l2_clk_unregister_fixed(struct v4l2_clk *clk);
61
v4l2_clk_register_fixed(const char * dev_id,unsigned long rate)62 static inline struct v4l2_clk *v4l2_clk_register_fixed(const char *dev_id,
63 unsigned long rate)
64 {
65 return __v4l2_clk_register_fixed(dev_id, rate, THIS_MODULE);
66 }
67
68 #define V4L2_CLK_NAME_SIZE 64
69
70 #define v4l2_clk_name_i2c(name, size, adap, client) snprintf(name, size, \
71 "%d-%04x", adap, client)
72
73 #define v4l2_clk_name_of(name, size, node) snprintf(name, size, \
74 "of-%pOF", node)
75
76 #endif
77