/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* v4l2-mc.h - Media Controller V4L2 types and prototypes
*
* Copyright (C) 2016 Mauro Carvalho Chehab <mchehab@kernel.org>
* Copyright (C) 2006-2010 Nokia Corporation
* Copyright (c) 2016 Intel Corporation.
*/
#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 subdev pad.
*
* @src_sd: pointer to a source subdev
* @sink: pointer to a subdev sink pad
*
* 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 subdevice, in its v4l2-async notifier subdev bound
* callback, to create links from a bound source subdevice.
*
* .. note::
*
* Any sink subdevice that calls this function must implement the
* .get_fwnode_pad media operation in order to verify endpoints passed
* to the sink are owned by the sink.
*
* Return 0 on success or a negative error code on failure.
*/
int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
struct media_pad *sink);
/**
* v4l2_create_fwnode_links - Create fwnode-based links from a source
* subdev to a sink subdev.
*
* @src_sd: pointer to a source subdevice
* @sink_sd: pointer to a sink subdevice
*
* This function searches for any and all fwnode endpoint connections
* between source and sink subdevices, and translates them into media
* links. The function can be called by the sink subdevice, in its
* v4l2-async notifier subdev bound callback, to create all links from
* a bound source subdevice.
*
* .. note::
*
* Any sink subdevice that calls this function must implement the
* .get_fwnode_pad media operation in order to verify endpoints passed
* to the sink are owned by the sink.
*
* Return 0 on success or a negative error code on failure.
*/
int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd,
struct v4l2_subdev *sink_sd);
/**
* v4l2_pipeline_pm_get - Increase the use count of a pipeline
* @entity: The root entity of a pipeline
*
* Update the use count of all entities in the pipeline and power entities on.
*
* This function is intended to be called in video node open. It uses
* struct media_entity.use_count to track the power status. The use
* of this function should be paired with v4l2_pipeline_link_notify().
*
* Return 0 on success or a negative error code on failure.
*/
int v4l2_pipeline_pm_get(struct media_entity *entity);
/**
* v4l2_pipeline_pm_put - Decrease the use count of a pipeline
* @entity: The root entity of a pipeline
*
* Update the use count of all entities in the pipeline and power entities off.
*
* This function is intended to be called in video node release. It uses
* struct media_entity.use_count to track the power status. The use
* of this function should be paired with v4l2_pipeline_link_notify().
*/
void v4l2_pipeline_pm_put(struct media_entity *entity);
/**
* v4l2_pipeline_link_notify - Link management notification callback
* @link: The link
* @flags: New link flags that will be applied
* @notification: The link's state change notification type (MEDIA_DEV_NOTIFY_*)
*
* React to link management on powered pipelines by updating the use count of
* all entities in the source and sink sides of the link. Entities are powered
* on or off accordingly. The use of this function should be paired
* with v4l2_pipeline_pm_{get,put}().
*
* Return 0 on success or a negative error code on failure. Powering entities
* off is assumed to never fail. This function will not fail for disconnection
* events.
*/
int v4l2_pipeline_link_notify(struct media_link *link, u32 flags,
unsigned int notification);
#else /* CONFIG_MEDIA_CONTROLLER */
static inline int v4l2_mc_create_media_graph(struct media_device *mdev)
{
return 0;
}
static inline int v4l_enable_media_source(struct video_device *vdev)
{
return 0;
}
static inline void v4l_disable_media_source(struct video_device *vdev)
{
}
static inline int v4l_vb2q_enable_media_source(struct vb2_queue *q)
{
return 0;
}
static inline int v4l2_pipeline_pm_get(struct media_entity *entity)
{
return 0;
}
static inline void v4l2_pipeline_pm_put(struct media_entity *entity)
{}
static inline int v4l2_pipeline_link_notify(struct media_link *link, u32 flags,
unsigned int notification)
{
return 0;
}
#endif /* CONFIG_MEDIA_CONTROLLER */
#endif /* _V4L2_MC_H */
