[media] v4l: vsp1: Prevent multiple streamon race commencing pipeline early
With multiple inputs through the BRU it is feasible for the streams to race each other at stream-on. Multiple VIDIOC_STREAMON calls racing each other could have process N-1 skipping over the pipeline setup section and then start the pipeline early, if videobuf2 has already enqueued buffers to the driver for process N but not called the .start_streaming() operation yet In the case of the video pipelines, this can present two serious issues. 1) A null-dereference if the pipe->dl is committed at the same time as the vsp1_video_setup_pipeline() is processing 2) A hardware hang, where a display list is committed without having called vsp1_video_setup_pipeline() first Repair this issue, by ensuring that only the stream which configures the pipeline is able to start it. Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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