Hi, > > I'm aware of one more bug which affects my Etron: if an error occurs > > on an isochronous TD, two events are generated: first the error, > > then "success", even if the error is on the final TRB (the common > > case). Then the "success" causes "TRB DMA not part of current TD" > > warning. I suspect that all Etron chips are the same. This should > > be easily reproducible by unpligging an audio/video device while > > streaming. > > Hmm, I don't encounter this problem. OK, I know what happened. This bug only affects SuperSpeed isochronous endpoints. If you don't have this kind of device, you will not see it. I checked that High-speed isochronous errors are reported correctly. My motivation to develop a workaround for this bug has just decreased another notch. On the other hand, I was unable to reproduce the control transfer bug. The exact chip I have is labeled "EtronTech EJ168A", for the record. You are right, not all transfers have the data stage and transactions get out of sync with segment boundaries. I modified the patch to only print a warning instead of queuing a No-Op and then did various things which use control transactions: setting baud rate on serial, changing the volume on audio, starting video recording on a webcam, running ethtool on a NIC. The warning was printed a few times, but nothing interesting happened. Dynamic debug was enabled on handle_tx_event() - no errors reported. Maybe a different silicon/firmware revision, or maybe it's another SuperSpeed-only bug, or other special conditions for it to happen? > Ok, I will use one quirk XHCI_ETRON_HOST for these workarounds in the > next patch revision. That was just a suggestion, you should ask Mathias Nyman, I suppose. But, again, my impression of this hardware is that it's pretty bad and full of bugs, and they are bizarre enough to likely be unique. Regards, Michal
