Implicit feedback on BOSS GT-1, the saga continues...

Lucas jaffa225man at gmail.com
Thu Apr 8 05:25:16 CEST 2021 

Oh, nevermind about the dyndbg, a quick search shows it's a kernel module
option (modprobe.d) for my case:
https://www.kernel.org/doc/html/v4.15/admin-guide/dynamic-debug-howto.html


On Wed, Apr 7, 2021 at 10:08 PM Lucas <jaffa225man at gmail.com> wrote:

> That sounds like a good test.  I'm building it with the patch you posted
> earlier today, except pertaining to my Roland Boutique D-05 ID.  It will
> take a while before I have the result, though.  Also, that
> "snd_usb_audio.dyndbg=+p" is just a kernel boot (not build) option,
> correct?:
> I hope so, or I'll have to start the build over yet again. ;)
>
> On Wed, Apr 7, 2021 at 9:48 PM Mike Oliphant <oliphant at nostatic.org>
> wrote:
>
>> 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 at gmail.com>
>> 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 at nostatic.org>
>> > 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 at gmail.com> wrote:
>> >>
>> >>> Em Qua, 7 de abr de 2021 17:16, Mike Oliphant <oliphant at nostatic.org>
>> >>> 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 at gmail.com> 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@suse.de/
>> >>>>>
>> >>>>> Em Qua, 7 de abr de 2021 16:55, Mike Oliphant <
>> oliphant at nostatic.org>
>> >>>>> 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.
>> >>>>>>
>> >>>>>
>>
>
>
> --
> Protect your digital freedom and privacy, eliminate DRM, learn more at
> http://www.defectivebydesign.org/what_is_drm
> On a related note, also see https://www.fsf.org/campaigns/surveillance
>


-- 
Protect your digital freedom and privacy, eliminate DRM, learn more at
http://www.defectivebydesign.org/what_is_drm
On a related note, also see https://www.fsf.org/campaigns/surveillance

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