v4l2_pipeline_pm_use — Update the use count of an entity
int v4l2_pipeline_pm_use ( | struct media_entity * entity, |
int use); |
Update the use count of all entities in the pipeline and power entities on or off accordingly.
This function is intended to be called in video node open (use ==
1) and release (use == 0). It uses struct media_entity.use_count to
track the power status. The use of this function should be paired
with v4l2_pipeline_link_notify.
Return 0 on success or a negative error code on failure. Powering entities off is assumed to never fail. No failure can occur when the use parameter is set to 0.