Commit d9f44345 authored by Tomi Valkeinen's avatar Tomi Valkeinen Committed by Mauro Carvalho Chehab
Browse files

media: mc: entity: add alloc variant of pipeline_start 



Add new variant of media_pipeline_start(), media_pipeline_alloc_start().

media_pipeline_alloc_start() can be used by drivers that do not need to
extend the media_pipeline. The function will either use the pipeline
already associated with the entity, if such exists, or allocate a new
pipeline.

When media_pipeline_stop() is called and the pipeline's use count drops
to zero, the pipeline is automatically freed.

Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: default avatarLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
parent 98d79dc3

drivers/media/mc/mc-entity.c

+38 −0
Original line number Diff line number Diff line
@@ -530,6 +530,8 @@ void __media_pipeline_stop(struct media_entity *entity) 


	media_graph_walk_cleanup(graph);



	if (pipe->allocated)

		kfree(pipe);

}

EXPORT_SYMBOL_GPL(__media_pipeline_stop);
@@ -543,6 +545,42 @@ void media_pipeline_stop(struct media_entity *entity) 
}

EXPORT_SYMBOL_GPL(media_pipeline_stop);



__must_check int media_pipeline_alloc_start(struct media_entity *entity)

{

	struct media_device *mdev = entity->graph_obj.mdev;

	struct media_pipeline *new_pipe = NULL;

	struct media_pipeline *pipe;

	int ret;



	mutex_lock(&mdev->graph_mutex);



	/*

	 * Is the entity already part of a pipeline? If not, we need to allocate

	 * a pipe.

	 */

	pipe = media_entity_pipeline(entity);

	if (!pipe) {

		new_pipe = kzalloc(sizeof(*new_pipe), GFP_KERNEL);

		if (!new_pipe) {

			ret = -ENOMEM;

			goto out;

		}



		pipe = new_pipe;

		pipe->allocated = true;

	}



	ret = __media_pipeline_start(entity, pipe);

	if (ret)

		kfree(new_pipe);



out:

	mutex_unlock(&mdev->graph_mutex);



	return ret;

}

EXPORT_SYMBOL_GPL(media_pipeline_alloc_start);



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

 * Links management

 */

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

+11 −0
Original line number Diff line number Diff line
@@ -1143,6 +1143,17 @@ void __video_device_pipeline_stop(struct video_device *vdev) 
}

EXPORT_SYMBOL_GPL(__video_device_pipeline_stop);



__must_check int video_device_pipeline_alloc_start(struct video_device *vdev)

{

	struct media_entity *entity = &vdev->entity;



	if (entity->num_pads != 1)

		return -ENODEV;



	return media_pipeline_alloc_start(entity);

}

EXPORT_SYMBOL_GPL(video_device_pipeline_alloc_start);



struct media_pipeline *video_device_pipeline(struct video_device *vdev)

{

	struct media_entity *entity = &vdev->entity;

include/media/media-entity.h

+15 −0
Original line number Diff line number Diff line
@@ -100,10 +100,12 @@ struct media_graph { 
/**

 * struct media_pipeline - Media pipeline related information

 *

 * @allocated:		Media pipeline allocated and freed by the framework

 * @start_count:	Media pipeline start - stop count

 * @graph:		Media graph walk during pipeline start / stop

 */

struct media_pipeline {

	bool allocated;

	int start_count;

	struct media_graph graph;

};
@@ -1092,6 +1094,19 @@ void media_pipeline_stop(struct media_entity *entity); 
 */

void __media_pipeline_stop(struct media_entity *entity);



/**

 * media_pipeline_alloc_start - Mark a pipeline as streaming

 * @entity: Starting entity

 *

 * media_pipeline_alloc_start() is similar to media_pipeline_start() but instead

 * of working on a given pipeline the function will use an existing pipeline if

 * the entity is already part of a pipeline, or allocate a new pipeline.

 *

 * Calls to media_pipeline_alloc_start() must be matched with

 * media_pipeline_stop().

 */

__must_check int media_pipeline_alloc_start(struct media_entity *entity);



/**

 * media_devnode_create() - creates and initializes a device node interface

 *

include/media/v4l2-dev.h

+14 −0
Original line number Diff line number Diff line
@@ -607,6 +607,20 @@ void video_device_pipeline_stop(struct video_device *vdev); 
 */

void __video_device_pipeline_stop(struct video_device *vdev);



/**

 * video_device_pipeline_alloc_start - Mark a pipeline as streaming

 * @vdev: Starting video device

 *

 * video_device_pipeline_alloc_start() is similar to video_device_pipeline_start()

 * but instead of working on a given pipeline the function will use an

 * existing pipeline if the video device is already part of a pipeline, or

 * allocate a new pipeline.

 *

 * Calls to video_device_pipeline_alloc_start() must be matched with

 * video_device_pipeline_stop().

 */

__must_check int video_device_pipeline_alloc_start(struct video_device *vdev);



/**

 * video_device_pipeline - Get the media pipeline a video device is part of

 * @vdev: The video device