Checking pipeline hang status

[David Röthlisberger]

On 21 Oct 2013, at 17:31, Baby Octopus wrote:
> Just wondering if there is any way to check if a particular pipeline is hung
> for some reason, so that it can be restarted under such circumstances. More
> of a guard band. Any input? :)

I don't know if this is the best way to do it, but in stb-tester we put
a queue in the pipeline and we register for the queue's "underrun" and
"running" signals.

On underrun: Set 1 second timer to restart the pipeline.
On running: Cancel the timer.