include/media/v4l2-mc.h

Source file repositories/reference/linux-study-clean/include/media/v4l2-mc.h

File Facts

System
Linux kernel
Corpus path
include/media/v4l2-mc.h
Extension
.h
Size
7971 bytes
Lines
233
Domain
Repository Root And Misc
Bucket
include
Inferred role
Repository Root And Misc: implementation source
Status
source implementation candidate

Why This File Exists

Top-level or miscellaneous repository surface. Use this as map coverage unless a later manual pass promotes the file into a deeper subsystem dossier.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _V4L2_MC_H
#define _V4L2_MC_H

#include <media/media-device.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-subdev.h>
#include <linux/types.h>

/* We don't need to include pci.h or usb.h here */
struct pci_dev;
struct usb_device;

#ifdef CONFIG_MEDIA_CONTROLLER
/**
 * v4l2_mc_create_media_graph() - create Media Controller links at the graph.
 *
 * @mdev:	pointer to the &media_device struct.
 *
 * Add links between the entities commonly found on PC customer's hardware at
 * the V4L2 side: camera sensors, audio and video PLL-IF decoders, tuners,
 * analog TV decoder and I/O entities (video, VBI and Software Defined Radio).
 *
 * .. note::
 *
 *    Webcams are modelled on a very simple way: the sensor is
 *    connected directly to the I/O entity. All dirty details, like
 *    scaler and crop HW are hidden. While such mapping is enough for v4l2
 *    interface centric PC-consumer's hardware, V4L2 subdev centric camera
 *    hardware should not use this routine, as it will not build the right graph.
 */
int v4l2_mc_create_media_graph(struct media_device *mdev);

/**
 * v4l_enable_media_source() -	Hold media source for exclusive use
 *				if free
 *
 * @vdev:	pointer to struct video_device
 *
 * This interface calls enable_source handler to determine if
 * media source is free for use. The enable_source handler is
 * responsible for checking is the media source is free and
 * start a pipeline between the media source and the media
 * entity associated with the video device. This interface
 * should be called from v4l2-core and dvb-core interfaces
 * that change the source configuration.
 *
 * Return: returns zero on success or a negative error code.
 */
int v4l_enable_media_source(struct video_device *vdev);

/**
 * v4l_disable_media_source() -	Release media source
 *
 * @vdev:	pointer to struct video_device
 *
 * This interface calls disable_source handler to release
 * the media source. The disable_source handler stops the
 * active media pipeline between the media source and the
 * media entity associated with the video device.
 *
 * Return: returns zero on success or a negative error code.
 */
void v4l_disable_media_source(struct video_device *vdev);

/*
 * v4l_vb2q_enable_media_tuner -  Hold media source for exclusive use
 *				  if free.
 * @q - pointer to struct vb2_queue
 *
 * Wrapper for v4l_enable_media_source(). This function should
 * be called from v4l2-core to enable the media source with
 * pointer to struct vb2_queue as the input argument. Some
 * v4l2-core interfaces don't have access to video device and
 * this interface finds the struct video_device for the q and
 * calls v4l_enable_media_source().
 */
int v4l_vb2q_enable_media_source(struct vb2_queue *q);

/**
 * v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a
 *                                   source subdev to a sink pad.
 *
 * @src_sd: pointer to a source subdev
 * @sink:  pointer to a sink pad
 * @flags: the link flags
 *
 * This function searches for fwnode endpoint connections from a source
 * subdevice to a single sink pad, and if suitable connections are found,
 * translates them into media links to that pad. The function can be
 * called by the sink, in its v4l2-async notifier bound callback, to create

Annotation

Implementation Notes