On Wed, Aug 28, 2013 at 7:46 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Wed, 28 Aug 2013, Clemens Ladisch wrote: > >> Sorry, what I said applies more to explicit sync endpoints. When using >> implicit sync, a playback URB is submitted for each completed capture >> URB, with the number of samples per packet identical to the >> corresponding capture packet, so the parameters must be identical. > > Got it. Below is an updated patch. > > James, the problem you encountered was most likely a result of the > faulty treatment of capture endpoints that Clemens pointed out. It was > quite obvious in the usbmon traces that the unpatched driver used 8 > packets per URB whereas the patched driver used 22. This updated patch > should fix that problem. > Works fine. With this, it is possible to get clear playback at 64 frames/period too. With vanilla 3.10.9, there was some glitchy distortion to the sound at that latency, so this seems to be an improvement. James -- 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
