Commit 0d3c81e8 authored by Steve Longerbeam's avatar Steve Longerbeam Committed by Mauro Carvalho Chehab
Browse files

media: v4l2-mc: add v4l2_create_fwnode_links helpers 



Add functions to create media links between source and sink subdevices,
based on the fwnode endpoint connections between them:

v4l2_create_fwnode_links_to_pad() - create links from a source subdev to
                                    a single sink pad based on fwnode
                                    endpoint connections.

v4l2_create_fwnode_links() - create all links from a source to sink subdev
                             based on fwnode endpoint connections.

These functions can be used in a sink's v4l2-async notifier subdev
bound callback to make the links from the bound subdev.

Signed-off-by: default avatarSteve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent 8fe784b9

drivers/media/v4l2-core/v4l2-mc.c

+95 −0
Original line number Diff line number Diff line
@@ -309,6 +309,101 @@ int v4l_vb2q_enable_media_source(struct vb2_queue *q) 
}

EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source);



int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,

				    struct media_pad *sink)

{

	struct fwnode_handle *endpoint;

	struct v4l2_subdev *sink_sd;



	if (!(sink->flags & MEDIA_PAD_FL_SINK) ||

	    !is_media_entity_v4l2_subdev(sink->entity))

		return -EINVAL;



	sink_sd = media_entity_to_v4l2_subdev(sink->entity);



	fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {

		struct fwnode_handle *remote_ep;

		int src_idx, sink_idx, ret;

		struct media_pad *src;



		src_idx = media_entity_get_fwnode_pad(&src_sd->entity,

						      endpoint,

						      MEDIA_PAD_FL_SOURCE);

		if (src_idx < 0)

			continue;



		remote_ep = fwnode_graph_get_remote_endpoint(endpoint);

		if (!remote_ep)

			continue;



		/*

		 * ask the sink to verify it owns the remote endpoint,

		 * and translate to a sink pad.

		 */

		sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,

						       remote_ep,

						       MEDIA_PAD_FL_SINK);

		fwnode_handle_put(remote_ep);



		if (sink_idx < 0 || sink_idx != sink->index)

			continue;



		/*

		 * the source endpoint corresponds to one of its source pads,

		 * the source endpoint connects to an endpoint at the sink

		 * entity, and the sink endpoint corresponds to the sink

		 * pad requested, so we have found an endpoint connection

		 * that works, create the media link for it.

		 */



		src = &src_sd->entity.pads[src_idx];



		/* skip if link already exists */

		if (media_entity_find_link(src, sink))

			continue;



		dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",

			src_sd->entity.name, src_idx,

			sink_sd->entity.name, sink_idx);



		ret = media_create_pad_link(&src_sd->entity, src_idx,

					    &sink_sd->entity, sink_idx, 0);

		if (ret) {

			dev_err(sink_sd->dev,

				"link %s:%d -> %s:%d failed with %d\n",

				src_sd->entity.name, src_idx,

				sink_sd->entity.name, sink_idx, ret);



			fwnode_handle_put(endpoint);

			return ret;

		}

	}



	return 0;

}

EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links_to_pad);



int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd,

			     struct v4l2_subdev *sink_sd)

{

	unsigned int i;



	for (i = 0; i < sink_sd->entity.num_pads; i++) {

		struct media_pad *pad = &sink_sd->entity.pads[i];

		int ret;



		if (!(pad->flags & MEDIA_PAD_FL_SINK))

			continue;



		ret = v4l2_create_fwnode_links_to_pad(src_sd, pad);

		if (ret)

			return ret;

	}



	return 0;

}

EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links);



/* -----------------------------------------------------------------------------

 * Pipeline power management

 *

include/media/v4l2-mc.h

+48 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 


#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 */
@@ -84,6 +85,53 @@ void v4l_disable_media_source(struct video_device *vdev); 
 */

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