> >> I guess UAC1 doesn't need feedback endpoints, right? Seems like that > >> should be something specific to UAC2. At least for now. > > > > It seems like it is needed there aswell, see > > http://www.usb.org/developers/docs/devclass_docs/audio10.pdf (3.7.2.2) > > (Feedback endpoint == Synch Endpoint) > > fair enough, then it could be done generically in u_audio.c Ok, but I guess for the generic case (when it is possible to calculate the feedback value) that lower levels need to provide f.i. the high resolution timestamps of SOF IRQs to upper levels ? In the ALSA subsystem case, the calculation is straightforward and static. I don't know if you saw my proposal for a new UAC2 gadget upper level implementation, where the gadget should be exposed as a JACK client. In this case, there would be need for those SOF timestamps to be able to calculate the feedback value. Regards /Robert -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html