[media] media: entity: Catch unbalanced media_pipeline_stop calls

Drivers must not perform unbalanced calls to stop the entity pipeline,
however if they do they will fault in the core media code, as the
entity->pipe will be set as NULL. We handle this gracefully in the core
with a WARN for the developer.

Replace the erroneous check on zero streaming counts, with a check on
NULL pipe elements instead, as this is the symptom of unbalanced
media_pipeline_stop calls.

Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pincharts@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Kieran Bingham 2017-01-03 11:12:11 -02:00 committed by Mauro Carvalho Chehab
parent 8780f1d9d6
commit 2a2599c663

View File

@ -566,8 +566,13 @@ void __media_pipeline_stop(struct media_entity *entity)
struct media_graph *graph = &entity->pipe->graph;
struct media_pipeline *pipe = entity->pipe;
/*
* If the following check fails, the driver has performed an
* unbalanced call to media_pipeline_stop()
*/
if (WARN_ON(!pipe))
return;
WARN_ON(!pipe->streaming_count);
media_graph_walk_start(graph, entity);
while ((entity = media_graph_walk_next(graph))) {