linux-sg2042/include/media/v4l2-async.h

139 lines
4.0 KiB
C

/*
* V4L2 asynchronous subdevice registration API
*
* 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.
*/
#ifndef V4L2_ASYNC_H
#define V4L2_ASYNC_H
#include <linux/list.h>
#include <linux/mutex.h>
struct device;
struct device_node;
struct v4l2_device;
struct v4l2_subdev;
struct v4l2_async_notifier;
/* A random max subdevice number, used to allocate an array on stack */
#define V4L2_MAX_SUBDEVS 128U
/**
* enum v4l2_async_match_type - type of asynchronous subdevice logic to be used
* in order to identify a match
*
* @V4L2_ASYNC_MATCH_CUSTOM: Match will use the logic provided by &struct
* v4l2_async_subdev.match ops
* @V4L2_ASYNC_MATCH_DEVNAME: Match will use the device name
* @V4L2_ASYNC_MATCH_I2C: Match will check for I2C adapter ID and address
* @V4L2_ASYNC_MATCH_FWNODE: Match will use firmware node
*
* This enum is used by the asyncrhronous sub-device logic to define the
* algorithm that will be used to match an asynchronous device.
*/
enum v4l2_async_match_type {
V4L2_ASYNC_MATCH_CUSTOM,
V4L2_ASYNC_MATCH_DEVNAME,
V4L2_ASYNC_MATCH_I2C,
V4L2_ASYNC_MATCH_FWNODE,
};
/**
* struct v4l2_async_subdev - sub-device descriptor, as known to a bridge
*
* @match_type: type of match that will be used
* @match: union of per-bus type matching data sets
* @list: used to link struct v4l2_async_subdev objects, waiting to be
* probed, to a notifier->waiting list
*/
struct v4l2_async_subdev {
enum v4l2_async_match_type match_type;
union {
struct {
struct fwnode_handle *fwnode;
} fwnode;
struct {
const char *name;
} device_name;
struct {
int adapter_id;
unsigned short address;
} i2c;
struct {
bool (*match)(struct device *,
struct v4l2_async_subdev *);
void *priv;
} custom;
} match;
/* v4l2-async core private: not to be used by drivers */
struct list_head list;
};
/**
* struct v4l2_async_notifier - v4l2_device notifier data
*
* @num_subdevs: number of subdevices
* @subdevs: array of pointers to subdevice descriptors
* @v4l2_dev: pointer to struct v4l2_device
* @waiting: list of struct v4l2_async_subdev, waiting for their drivers
* @done: list of struct v4l2_subdev, already probed
* @list: member in a global list of notifiers
* @bound: a subdevice driver has successfully probed one of subdevices
* @complete: all subdevices have been probed successfully
* @unbind: a subdevice is leaving
*/
struct v4l2_async_notifier {
unsigned int num_subdevs;
struct v4l2_async_subdev **subdevs;
struct v4l2_device *v4l2_dev;
struct list_head waiting;
struct list_head done;
struct list_head list;
int (*bound)(struct v4l2_async_notifier *notifier,
struct v4l2_subdev *subdev,
struct v4l2_async_subdev *asd);
int (*complete)(struct v4l2_async_notifier *notifier);
void (*unbind)(struct v4l2_async_notifier *notifier,
struct v4l2_subdev *subdev,
struct v4l2_async_subdev *asd);
};
/**
* v4l2_async_notifier_register - registers a subdevice asynchronous notifier
*
* @v4l2_dev: pointer to &struct v4l2_device
* @notifier: pointer to &struct v4l2_async_notifier
*/
int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
struct v4l2_async_notifier *notifier);
/**
* v4l2_async_notifier_unregister - unregisters a subdevice asynchronous notifier
*
* @notifier: pointer to &struct v4l2_async_notifier
*/
void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier);
/**
* v4l2_async_register_subdev - registers a sub-device to the asynchronous
* subdevice framework
*
* @sd: pointer to &struct v4l2_subdev
*/
int v4l2_async_register_subdev(struct v4l2_subdev *sd);
/**
* v4l2_async_unregister_subdev - unregisters a sub-device to the asynchronous
* subdevice framework
*
* @sd: pointer to &struct v4l2_subdev
*/
void v4l2_async_unregister_subdev(struct v4l2_subdev *sd);
#endif