include/media/v4l2-clk.h

   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 v4l2_clk {
  26         struct list_head list;
  27         const struct v4l2_clk_ops *ops;
  28         const char *dev_id;
  29         const char *id;
  30         int enable;
  31         struct mutex lock; /* Protect the enable count */
  32         atomic_t use_count;
  33         void *priv;
  34 };
  35
  36 struct v4l2_clk_ops {
  37         struct module   *owner;
  38         int             (*enable)(struct v4l2_clk *clk);
  39         void            (*disable)(struct v4l2_clk *clk);
  40         unsigned long   (*get_rate)(struct v4l2_clk *clk);
  41         int             (*set_rate)(struct v4l2_clk *clk, unsigned long);
  42 };
  43
  44 struct v4l2_clk *v4l2_clk_register(const struct v4l2_clk_ops *ops,
  45                                    const char *dev_name,
  46                                    const char *name, void *priv);
  47 void v4l2_clk_unregister(struct v4l2_clk *clk);
  48 struct v4l2_clk *v4l2_clk_get(struct device *dev, const char *id);
  49 void v4l2_clk_put(struct v4l2_clk *clk);
  50 int v4l2_clk_enable(struct v4l2_clk *clk);
  51 void v4l2_clk_disable(struct v4l2_clk *clk);
  52 unsigned long v4l2_clk_get_rate(struct v4l2_clk *clk);
  53 int v4l2_clk_set_rate(struct v4l2_clk *clk, unsigned long rate);
  54
  55 struct module;
  56
  57 struct v4l2_clk *__v4l2_clk_register_fixed(const char *dev_id,
  58                 const char *id, unsigned long rate, struct module *owner);
  59 void v4l2_clk_unregister_fixed(struct v4l2_clk *clk);
  60
  61 static inline struct v4l2_clk *v4l2_clk_register_fixed(const char *dev_id,
  62                                                         const char *id,
  63                                                         unsigned long rate)
  64 {
  65         return __v4l2_clk_register_fixed(dev_id, id, rate, THIS_MODULE);
  66 }
  67
  68 #define v4l2_clk_name_i2c(name, size, adap, client) snprintf(name, size, \
  69                           "%d-%04x", adap, client)
  70
  71 #endif