Hi Tian Shu, On 09/04/2018 07:01 AM, Qiu, Tian Shu wrote: > Hi, > > Raise my point. > The case here is that we have multiple sensors connected to CIO2. The sensors work independently. So failure on one sensor should not block the function of the other. > That is, we should not rely on that all sensors are ready before allowing user to operate on the ready cameras. > Sometimes due to hardware issues or incompleteness, we did met the case that one sensor is not probing properly. And in this case, the current implementation blocks us using the working one. > What I can think now to solve this are: After discussing this with Sakari over IRC, I agree with you that $SUBJECT can do more harm than good and the patch should just be dropped. > 1. Register multiple media devices. One for each sensor path. This will increase media device count. > 2. Use .bound callback to create the link and register the subdev node for each sensor. Leave .complete empty. > Not sure if this breaks the rule of media framework. And also have not found an API to register one single subdev node. > I agree with your comment on (2) since currently the driver isn't able to cope with the case that you are describing, as you mention the links and the subdev node registration are done in the .complete callback. So that logic should be moved to the .bound callback instead, so the media graph is usable even if one of the drivers for a pending subdevice fails to probe. > Thanks > Tianshu Qiu > Best regards, -- Javier Martinez Canillas Software Engineer - Desktop Hardware Enablement Red Hat
