From a5ccc48a7c48610e7f92fa599406738d69195d51 Mon Sep 17 00:00:00 2001 From: Sakari Ailus Date: Sun, 7 Mar 2010 16:14:14 -0300 Subject: [media] media: Entity graph traversal Add media entity graph traversal. The traversal follows enabled links by depth first. Traversing graph backwards is prevented by comparing the next possible entity in the graph with the previous one. Multiply connected graphs are thus not supported. Signed-off-by: Sakari Ailus Signed-off-by: Laurent Pinchart Signed-off-by: Vimarsh Zutshi Acked-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- include/media/media-entity.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include') diff --git a/include/media/media-entity.h b/include/media/media-entity.h index f6c856c9ac1..28f61f6ee54 100644 --- a/include/media/media-entity.h +++ b/include/media/media-entity.h @@ -113,10 +113,25 @@ static inline u32 media_entity_subtype(struct media_entity *entity) return entity->type & MEDIA_ENT_SUBTYPE_MASK; } +#define MEDIA_ENTITY_ENUM_MAX_DEPTH 16 + +struct media_entity_graph { + struct { + struct media_entity *entity; + int link; + } stack[MEDIA_ENTITY_ENUM_MAX_DEPTH]; + int top; +}; + int media_entity_init(struct media_entity *entity, u16 num_pads, struct media_pad *pads, u16 extra_links); void media_entity_cleanup(struct media_entity *entity); int media_entity_create_link(struct media_entity *source, u16 source_pad, struct media_entity *sink, u16 sink_pad, u32 flags); +void media_entity_graph_walk_start(struct media_entity_graph *graph, + struct media_entity *entity); +struct media_entity * +media_entity_graph_walk_next(struct media_entity_graph *graph); + #endif -- cgit v1.2.3-70-g09d2