Hi Geraldo - I had the same thought and I have tried enabling playback feedback while turning off capture feedback without my endpoint patch. It doesn't work - at least not on the GT-1. Playback/capture fails to start. Speaking of testing, if you (or anyone else following this discussion) have one of these Roland/BOSS devices, it would be great if you could try testing with playback feedback enabled and my endpoint.c workaround. Mike On Wed, Apr 7, 2021 at 7:21 PM Geraldo Nascimento <geraldogabriel@xxxxxxxxx> wrote: > Thanks, Mike, one thing I can tell you right off the bat is that if you > turn implicit feedback sync on for both endpoints at the same time like you > mentioned, without your workaround inside endpoint.c, they most likely will > stall because they would both be waiting for each other to start. > > Have you tried engaging the generic implicit feedback sync just for the > playback, thereby commenting out the capture implicit feedback entries, and > re-enabling snd_usb_endpoint_implicit_feedback_sink(ep) inside endpoint.c? > Does playback still fail to start? > > If you choose to perform this simple test please share with us the test's > dyndbg logs right from the moment you turn on the device, not just after > you start jackd. > > Sorry for the endless do-this, do-that. Such is the pace of teledebugging > > > Em Qua, 7 de abr de 2021 21:38, Mike Oliphant <oliphant@xxxxxxxxxxxx> > escreveu: > >> Geraldo - here is the dmesg output when starting up jackd for >> capture/playback: >> >> With my patch: >> >> [ 136.734081] usb 3-1.2: Open EP 0x8e, iface=2:1, idx=0 >> [ 136.734088] usb 3-1.2: channels=2, rate=44100, format=S32_LE, >> period_bytes=256, periods=2, implicit_fb=0 >> [ 136.734092] usb 3-1.2: Setting usb interface 2:0 for EP 0x8e >> [ 136.734233] usb 3-1.2: Setting usb interface 2:1 for EP 0x8e >> [ 136.734381] usb 3-1.2: 2:1 Set sample rate 44100, clock 0 >> [ 136.734388] usb 3-1.2: Setting params for data EP 0x8e, pipe 0x70480 >> [ 136.734394] usb 3-1.2: Set up 12 URBS, ret=0 >> [ 136.734466] usb 3-1.2: Open EP 0xd, iface=1:1, idx=0 >> [ 136.734468] usb 3-1.2: channels=2, rate=44100, format=S32_LE, >> period_bytes=256, periods=2, implicit_fb=1 >> [ 136.734471] usb 3-1.2: Reopened EP 0x8e (count 1) >> [ 136.734473] usb 3-1.2: Setting usb interface 1:0 for EP 0xd >> [ 136.734605] usb 3-1.2: Setting usb interface 1:1 for EP 0xd >> [ 136.734762] usb 3-1.2: 1:1 Set sample rate 44100, clock 0 >> [ 136.734774] usb 3-1.2: Setting params for data EP 0xd, pipe 0x68400 >> [ 136.734781] usb 3-1.2: Set up 12 URBS, ret=0 >> [ 136.734830] usb 3-1.2: Starting data EP 0xd (running 0) >> [ 136.734873] usb 3-1.2: 12 URBs submitted for EP 0xd >> [ 136.734876] usb 3-1.2: Starting data EP 0x8e (running 0) >> [ 136.734906] usb 3-1.2: 12 URBs submitted for EP 0x8e >> [ 136.740627] usb 3-1.2: Starting data EP 0x8e (running 1) >> [ 136.740634] usb 3-1.2: 2:1 Start Capture PCM >> [ 136.740635] usb 3-1.2: 1:1 Start Playback PCM >> >> >> With the unpatched kernel: >> >> [ 344.813203] usb 3-1.2: Open EP 0x8e, iface=2:1, idx=0 >> [ 344.813210] usb 3-1.2: channels=2, rate=44100, format=S32_LE, >> period_bytes=256, periods=2, implicit_fb=1 >> [ 344.813213] usb 3-1.2: Open EP 0xd, iface=1:1, idx=0 >> [ 344.813215] usb 3-1.2: channels=2, rate=44100, format=S32_LE, >> period_bytes=256, periods=2, implicit_fb=0 >> [ 344.813217] usb 3-1.2: Setting usb interface 2:0 for EP 0x8e >> [ 344.813367] usb 3-1.2: Setting usb interface 2:1 for EP 0x8e >> [ 344.813494] usb 3-1.2: 2:1 Set sample rate 44100, clock 0 >> [ 344.813503] usb 3-1.2: Setting params for data EP 0x8e, pipe 0x70580 >> [ 344.813509] usb 3-1.2: Set up 12 URBS, ret=0 >> [ 344.813513] usb 3-1.2: Setting usb interface 1:0 for EP 0xd >> [ 344.813587] usb 3-1.2: Setting usb interface 1:1 for EP 0xd >> [ 344.813758] usb 3-1.2: 1:1 Set sample rate 44100, clock 0 >> [ 344.813765] usb 3-1.2: Setting params for data EP 0xd, pipe 0x68500 >> [ 344.813770] usb 3-1.2: Set up 2 URBS, ret=0 >> [ 344.813858] usb 3-1.2: Reopened EP 0xd (count 1) >> [ 344.813883] usb 3-1.2: Starting data EP 0xd (running 0) >> [ 344.813899] usb 3-1.2: 2 URBs submitted for EP 0xd >> [ 344.819499] usb 3-1.2: Starting data EP 0x8e (running 0) >> [ 344.819532] usb 3-1.2: 12 URBs submitted for EP 0x8e >> [ 344.819535] usb 3-1.2: Starting data EP 0xd (running 1) >> [ 344.819538] usb 3-1.2: 2:1 Start Capture PCM >> [ 344.819540] usb 3-1.2: 1:1 Start Playback PCM >> [ 344.820663] usb 3-1.2: Stopping data EP 0xd (running 2) >> [ 344.820688] usb 3-1.2: Stopping data EP 0x8e (running 1) >> [ 344.820693] usb 3-1.2: 2:1 Stop Capture PCM >> [ 344.820695] usb 3-1.2: Stopping data EP 0xd (running 1) >> [ 344.820697] usb 3-1.2: 1:1 Stop Playback PCM >> [ 344.833799] usb 3-1.2: Starting data EP 0xd (running 0) >> [ 344.833852] usb 3-1.2: 2 URBs submitted for EP 0xd >> [ 344.833867] usb 3-1.2: Starting data EP 0x8e (running 0) >> [ 344.833888] usb 3-1.2: 12 URBs submitted for EP 0x8e >> [ 344.833890] usb 3-1.2: Starting data EP 0xd (running 1) >> [ 344.833891] usb 3-1.2: 2:1 Start Capture PCM >> [ 344.833893] usb 3-1.2: 1:1 Start Playback PCM >> >> On Wed, Apr 7, 2021 at 1:30 PM Geraldo Nascimento < >> geraldogabriel@xxxxxxxxx> wrote: >> >>> Em Qua, 7 de abr de 2021 17:16, Mike Oliphant <oliphant@xxxxxxxxxxxx> >>> escreveu: >>> >>>> Hi Geraldo - I don't have that patch applied, but it shouldn't make any >>>> behavioral difference - it just seems to be simplifying the code. >>>> >>> >>> Point taken. >>> >>> >>>> The issue is that the BOSS GT-1 *does* need implicit feedback on >>>> playback to avoid clock timing issues, and the current behavior is >>>> disabling that feedback. >>>> >>> >>> Mike, would you mind posting some dyndbg logs for both the stock >>> behaviour and your endpoint.c/generic quirk modified behaviour? >>> >>> Just add snd_usb_audio.dyndbg=+p to your kernel options and please share >>> the logs. >>> >>> >>>> Mike >>>> >>>> On Wed, Apr 7, 2021 at 1:04 PM Geraldo Nascimento < >>>> geraldogabriel@xxxxxxxxx> wrote: >>>> >>>>> Hey Mike, did you catch the latest patch by Takashi Iwai for capture >>>>> quirky devices? >>>>> >>>>> You can find it here: >>>>> https://patchwork.kernel.org/project/alsa-devel/patch/20210406113837.32041-1-tiwai@xxxxxxx/ >>>>> >>>>> Em Qua, 7 de abr de 2021 16:55, Mike Oliphant <oliphant@xxxxxxxxxxxx> >>>>> escreveu: >>>>> >>>>>> I had thought that the recent implicit feedback changes were fully >>>>>> working >>>>>> on the BOSS GT-1, but it turns out that I just hadn't tested well >>>>>> enough. >>>>>> >>>>>> Audio playback and capture works, but with periodic dropouts. I get >>>>>> the >>>>>> exact same behavior as I did with the quirk to completely disable >>>>>> implicit >>>>>> feedback. Without the implicit feedback, you get dropouts from clock >>>>>> drift >>>>>> - how bad probably varies from card to card. On mine it is every >>>>>> second or >>>>>> so. >>>>>> >>>>>> If I switch playback feedback for the GT-1 to generic by doing >>>>>> "IMPLICIT_FB_GENERIC_DEV(0x0582, 0x01d6)", I get the previous old >>>>>> behavior, >>>>>> which is that playback completely fails to start. >>>>>> >>>>>> With generic playback feedback, and using my previous patch to >>>>>> endpoint.c >>>>>> to avoid playback waiting on capture mentioned here: >>>>>> >>>>>> >>>>>> https://mailman.alsa-project.org/pipermail/alsa-devel/2020-January/161951.html >>>>>> >>>>>> playback and capture work perfectly for me. >>>>>> >>>>>
