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/*
* Media controller test application
*
* Copyright (C) 2010 Ideas on board SPRL <laurent.pinchart@ideasonboard.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#ifndef __MEDIA_H__
#define __MEDIA_H__
#include <linux/media.h>
struct media_link {
struct media_pad *source;
struct media_pad *sink;
struct media_link *twin;
__u32 flags;
__u32 padding[3];
};
struct media_pad {
struct media_entity *entity;
__u32 index;
__u32 flags;
__u32 padding[3];
};
struct media_entity {
struct media_entity_desc info;
struct media_pad *pads;
struct media_link *links;
unsigned int max_links;
unsigned int num_links;
char devname[32];
int fd;
__u32 padding[6];
};
struct media_device {
int fd;
struct media_entity *entities;
unsigned int entities_count;
__u32 padding[6];
};
/**
* @brief Open a media device.
* @param name - name (including path) of the device node.
* @param verbose - whether to print verbose information on the standard output.
*
* Open the media device referenced by @a name and enumerate entities, pads and
* links.
*
* @return A pointer to a newly allocated media_device structure instance on
* success and NULL on failure. The returned pointer must be freed with
* media_close when the device isn't needed anymore.
*/
struct media_device *media_open(const char *name, int verbose);
/**
* @brief Close a media device.
* @param media - device instance.
*
* Close the @a media device instance and free allocated resources. Access to the
* device instance is forbidden after this function returns.
*/
void media_close(struct media_device *media);
/**
* @brief Locate the pad at the other end of a link.
* @param pad - sink pad at one end of the link.
*
* Locate the source pad connected to @a pad through an enabled link. As only one
* link connected to a sink pad can be enabled at a time, the connected source
* pad is guaranteed to be unique.
*
* @return A pointer to the connected source pad, or NULL if all links connected
* to @a pad are disabled. Return NULL also if @a pad is not a sink pad.
*/
struct media_pad *media_entity_remote_source(struct media_pad *pad);
/**
* @brief Get the type of an entity.
* @param entity - the entity.
*
* @return The type of @a entity.
*/
static inline unsigned int media_entity_type(struct media_entity *entity)
{
return entity->info.type & MEDIA_ENTITY_TYPE_MASK;
}
/**
* @brief Find an entity by its name.
* @param media - media device.
* @param name - entity name.
* @param length - size of @a name.
*
* Search for an entity with a name equal to @a name.
*
* @return A pointer to the entity if found, or NULL otherwise.
*/
struct media_entity *media_get_entity_by_name(struct media_device *media,
const char *name, size_t length);
/**
* @brief Find an entity by its ID.
* @param media - media device.
* @param id - entity ID.
*
* Search for an entity with an ID equal to @a id.
*
* @return A pointer to the entity if found, or NULL otherwise.
*/
struct media_entity *media_get_entity_by_id(struct media_device *media,
__u32 id);
/**
* @brief Configure a link.
* @param media - media device.
* @param source - source pad at the link origin.
* @param sink - sink pad at the link target.
* @param flags - configuration flags.
*
* Locate the link between @a source and @a sink, and configure it by applying
* the new @a flags.
*
* Only the MEDIA_LINK_FLAG_ENABLED flag is writable.
*
* @return 0 on success, or a negative error code on failure.
*/
int media_setup_link(struct media_device *media,
struct media_pad *source, struct media_pad *sink,
__u32 flags);
/**
* @brief Reset all links to the disabled state.
* @param media - media device.
*
* Disable all links in the media device. This function is usually used after
* opening a media device to reset all links to a known state.
*
* @return 0 on success, or a negative error code on failure.
*/
int media_reset_links(struct media_device *media);
#endif
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