linux/include/media/v4l2-clk.h
Guennadi Liakhovetski 774cc4c289 [media] V4L2: add a v4l2-clk helper macro to produce an I2C device ID
To obtain a clock reference consumers supply their device object to the
V4L2 clock framework. The latter then uses the consumer device name to
find a matching clock. For that to work V4L2 clock providers have to
provide the same device name, when registering clocks. This patch adds
a helper macro to generate a suitable device name for I2C devices.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-10-31 04:33:02 -02:00

72 lines
2.0 KiB
C

/*
* V4L2 clock service
*
* Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* ATTENTION: This is a temporary API and it shall be replaced by the generic
* clock API, when the latter becomes widely available.
*/
#ifndef MEDIA_V4L2_CLK_H
#define MEDIA_V4L2_CLK_H
#include <linux/atomic.h>
#include <linux/export.h>
#include <linux/list.h>
#include <linux/mutex.h>
struct module;
struct device;
struct v4l2_clk {
struct list_head list;
const struct v4l2_clk_ops *ops;
const char *dev_id;
const char *id;
int enable;
struct mutex lock; /* Protect the enable count */
atomic_t use_count;
void *priv;
};
struct v4l2_clk_ops {
struct module *owner;
int (*enable)(struct v4l2_clk *clk);
void (*disable)(struct v4l2_clk *clk);
unsigned long (*get_rate)(struct v4l2_clk *clk);
int (*set_rate)(struct v4l2_clk *clk, unsigned long);
};
struct v4l2_clk *v4l2_clk_register(const struct v4l2_clk_ops *ops,
const char *dev_name,
const char *name, void *priv);
void v4l2_clk_unregister(struct v4l2_clk *clk);
struct v4l2_clk *v4l2_clk_get(struct device *dev, const char *id);
void v4l2_clk_put(struct v4l2_clk *clk);
int v4l2_clk_enable(struct v4l2_clk *clk);
void v4l2_clk_disable(struct v4l2_clk *clk);
unsigned long v4l2_clk_get_rate(struct v4l2_clk *clk);
int v4l2_clk_set_rate(struct v4l2_clk *clk, unsigned long rate);
struct module;
struct v4l2_clk *__v4l2_clk_register_fixed(const char *dev_id,
const char *id, unsigned long rate, struct module *owner);
void v4l2_clk_unregister_fixed(struct v4l2_clk *clk);
static inline struct v4l2_clk *v4l2_clk_register_fixed(const char *dev_id,
const char *id,
unsigned long rate)
{
return __v4l2_clk_register_fixed(dev_id, id, rate, THIS_MODULE);
}
#define v4l2_clk_name_i2c(name, size, adap, client) snprintf(name, size, \
"%d-%04x", adap, client)
#endif