Hi Hans, On Sunday, 4 February 2018 15:06:42 EET Hans Verkuil wrote: > Hi Mauro, > > I'm working on adding proper compliance tests for the MC but I think > something is missing in the G_TOPOLOGY ioctl w.r.t. pads. > > In several v4l-subdev ioctls you need to pass the pad. There the pad is an > index for the corresponding entity. I.e. an entity has 3 pads, so the pad > argument is [0-2]. > > The G_TOPOLOGY ioctl returns a pad ID, which is > 0x01000000. I can't use > that in the v4l-subdev ioctls, so how do I translate that to a pad index in > my application? > > It seems to be a missing feature in the API. I assume this information is > available in the core, so then I would add a field to struct media_v2_pad > with the pad index for the entity. > > Next time we add new public API features I want to see compliance tests > before accepting it. It's much too easy to overlook something, either in > the design or in a driver or in the documentation, so this is really, > really needed IMHO.
I agree with you, and would even like to go one step beyond by requiring an implementation in a real use case, not just in a compliance or test tool. On the topic of the G_TOPOLOGY API, it's pretty clear it was merged too hastily. We could try to fix it, but given all the issues we haven't solved yet, I believe a new version of the API would be better. -- Regards, Laurent Pinchart
