Hi Helen,
Thanks for your work.
On 2020-04-14 22:30:41 -0300, Helen Koike wrote:
> Add media_graph_walk_next_stream() function to follow links only from
> sink to source (not the opposite) to allow iteration only through the
> entities participating in a given stream.
>
> This is useful to allow calling .s_stream() callback only in the
> subdevices that requires to be enabled/disabled, and avoid calling this
> callback when not required.
>
> Signed-off-by: Helen Koike <helen.koike@xxxxxxxxxxxxx>
>
> ---
>
> Changes in v3:
> - Patch re-added in the series from version 1
>
> Changes in v2: None
>
> drivers/media/mc/mc-entity.c | 34 +++++++++++++++++++++++++++++++---
> include/media/media-entity.h | 15 +++++++++++++++
> 2 files changed, 46 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c
> index 211279c5fd77d..0d44c2de23e6f 100644
> --- a/drivers/media/mc/mc-entity.c
> +++ b/drivers/media/mc/mc-entity.c
> @@ -228,6 +228,11 @@ EXPORT_SYMBOL_GPL(media_entity_pads_init);
> * Graph traversal
> */
>
> +enum media_graph_walk_type {
> + MEDIA_GRAPH_WALK_CONNECTED_NODES,
> + MEDIA_GRAPH_WALK_STREAM_NODES,
> +};
> +
> static struct media_entity *
> media_entity_other(struct media_entity *entity, struct media_link *link)
> {
> @@ -305,7 +310,8 @@ void media_graph_walk_start(struct media_graph *graph,
> }
> EXPORT_SYMBOL_GPL(media_graph_walk_start);
>
> -static void media_graph_walk_iter(struct media_graph *graph)
> +static void media_graph_walk_iter(struct media_graph *graph,
> + enum media_graph_walk_type type)
> {
> struct media_entity *entity = stack_top(graph);
> struct media_link *link;
> @@ -326,6 +332,15 @@ static void media_graph_walk_iter(struct media_graph *graph)
> /* Get the entity in the other end of the link . */
> next = media_entity_other(entity, link);
>
> + if (type == MEDIA_GRAPH_WALK_STREAM_NODES
> + && next == link->sink->entity) {
> + link_top(graph) = link_top(graph)->next;
> + dev_dbg(entity->graph_obj.mdev->dev,
> + "walk: skipping '%s' (outside of the stream path)\n",
> + link->sink->entity->name);
> + return;
> + }
> +
> /* Has the entity already been visited? */
> if (media_entity_enum_test_and_set(&graph->ent_enum, next)) {
> link_top(graph) = link_top(graph)->next;
> @@ -342,7 +357,9 @@ static void media_graph_walk_iter(struct media_graph *graph)
> next->name);
> }
>
> -struct media_entity *media_graph_walk_next(struct media_graph *graph)
> +static struct media_entity *
> +__media_graph_walk_next(struct media_graph *graph,
> + enum media_graph_walk_type type)
> {
> struct media_entity *entity;
>
> @@ -355,7 +372,7 @@ struct media_entity *media_graph_walk_next(struct media_graph *graph)
> * found.
> */
> while (link_top(graph) != &stack_top(graph)->links)
> - media_graph_walk_iter(graph);
> + media_graph_walk_iter(graph, type);
>
> entity = stack_pop(graph);
> dev_dbg(entity->graph_obj.mdev->dev,
> @@ -363,8 +380,19 @@ struct media_entity *media_graph_walk_next(struct media_graph *graph)
>
> return entity;
> }
> +
> +struct media_entity *media_graph_walk_next(struct media_graph *graph)
> +{
> + return __media_graph_walk_next(graph, MEDIA_GRAPH_WALK_CONNECTED_NODES);
> +}
> EXPORT_SYMBOL_GPL(media_graph_walk_next);
>
> +struct media_entity *media_graph_walk_next_stream(struct media_graph *graph)
> +{
> + return __media_graph_walk_next(graph, MEDIA_GRAPH_WALK_STREAM_NODES);
One space to much after the ','. With this fixed,
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> +}
> +EXPORT_SYMBOL_GPL(media_graph_walk_next_stream);
> +
> int media_entity_get_fwnode_pad(struct media_entity *entity,
> struct fwnode_handle *fwnode,
> unsigned long direction_flags)
> diff --git a/include/media/media-entity.h b/include/media/media-entity.h
> index 8cb2c504a05c7..f17a5180ce524 100644
> --- a/include/media/media-entity.h
> +++ b/include/media/media-entity.h
> @@ -927,6 +927,21 @@ void media_graph_walk_start(struct media_graph *graph,
> */
> struct media_entity *media_graph_walk_next(struct media_graph *graph);
>
> +/**
> + * media_graph_walk_next_stream - Get the next entity in the graph
> + * @graph: Media graph structure
> + *
> + * Perform a depth-first traversal of the given media entities graph only
> + * following links from sink to source (and not the opposite).
> + *
> + * The graph structure must have been previously initialized with a call to
> + * media_graph_walk_start().
> + *
> + * Return: returns the next entity in the graph in the stream path
> + * or %NULL if the whole stream path have been traversed.
> + */
> +struct media_entity *media_graph_walk_next_stream(struct media_graph *graph);
> +
> /**
> * media_pipeline_start - Mark a pipeline as streaming
> * @entity: Starting entity
> --
> 2.26.0
>
--
Regards,
Niklas Söderlund
