Hi Guennadi, On Friday 30 Dec 2016 11:43:02 Guennadi Liakhovetski wrote: > Hi Laurent, > > I'd like to discuss extending this patch a bit, preferably as an > incremental patch. > > First let me confirm my current understanding of the way the UVC driver > creates its media device topology. Do I understand it correctly, that the > driver allocates UVC entities (not media controller entities) for all UVC > units and terminals, but then uses subdevices for all such UVC entities, > except terminals, i.e. only for UVC units? struct uvc_entity has an > embedded struct v4l2_subdev object, but it's unused for UVC terminals. > Instead terminals are associated to video devices, which are then linked > into the MC topology? Is this my understanding correct? That's correct, but looking at the code now, I think the driver should use a struct media_entity directly instead of a struct v4l2_subdev as it doesn't need any of the infrastructure provided by subdevs. > I have a problem with the current version of this patch, that there is no > way to associate video device nodes with respepctive metadata nodes. Would > it be acceptable to use an MC link for this association? No, links describe data connections. > Is it allowed for video device MC entities to have source pads additionally > to their (usually single) sink pad(s) (in case of input video devices)? If > that would be acceptable, I could create an additional patch to add a source > pad to output terminal video nodes to link it to metadata nodes. That's a hack, I don't think it's a good idea. -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
