hello , can anyone explain how callback is done in v4l2 test bench to update controls or its values? andrius: what callback? I don't quite get your question. hverkuil: how update on change works for controls? I was searching for a loop or something to see how application get current values all the time When apllication is running if I change one of the controls value with other apllication I can also see changes in test bench. So what method is used to check those changes andrius: It's listening to V4L2_EVENT_CTRL. Whenever a control changes value that event is sent. hverkuil: okay , ty hverkuil: thanks for the acks narmstrong: you're welcome! hverkuil: now the tricky question, I'm allowed to push them into drm-misc-next, but what about the media patches ? You need to ask Mauro, and he has to add his Ack as well. Yep, thanks