[PATCH] Fix mic sound on Jieli webcam

[Takashi Iwai]

On Thu, 17 Dec 2020 12:49:53 +0100,
Marco Giunta wrote:
> 
> Hi,
> thank you for your reply. As I told you, I'm not the guy who wrote the
> patch, but I try to continue his work.
> 
> > What's the original datainterval value for those altsettings?
> Where I can read the original datainterval value ? Is it an USB
> property (so I can search in udev) ? Or can I debug in some way the
> snd_usb_audio module load to get the values ?

bInterval in the descriptor should show the value.
At best, give the output of lsusb -v for the device.


thanks,

Takashi

> 
> Thanks,
>   Marco
> 
> 
> On Thu, Dec 17, 2020 at 10:50 AM Takashi Iwai <tiwai at suse.de> wrote:
> >
> > On Tue, 15 Dec 2020 10:44:45 +0100,
> > Marco Giunta wrote:
> > >
> > > Hi,
> > > recently I've bought a usb webcam with integrated mic:
> > >
> > >   Jieli Technology USB PHY 2.0 (1224:2a25)
> > >
> > > The video part works well, but the mic sound is speedups, "like
> > > minions" (cit.). When I connect the camera, these are the dmesg
> > > messages:
> > >
> > > kernel: usb 1-8: current rate 0 is different from the runtime rate 8000
> > > kernel: usb 1-8: current rate 0 is different from the runtime rate 16000
> > > kernel: usb 1-8: current rate 0 is different from the runtime rate 44100
> > > kernel: usb 1-8: current rate 0 is different from the runtime rate 48000
> > > kernel: usb 1-8: Warning! Unlikely big volume range (=4096), cval->res
> > > is probably wrong.
> > > kernel: usb 1-8: [3] FU [Mic Capture Volume] ch = 1, val = 0/4096/1
> > > kernel: usbcore: registered new interface driver snd-usb-audio
> > >
> > > and after a while, dmesg log is filled, every 5 seconds, with:
> > >
> > > kernel: retire_capture_urb: 84 callbacks suppressed
> > > kernel: retire_capture_urb: 1714 callbacks suppressed
> > >
> > > A guy reports on ArchLinux bug website the same problem
> > > (https://bugs.archlinux.org/task/68141?opened=12995&status%5B0%5D=)
> > > and provides a patch to fix the sound issue. I've applied the patch on
> > > kernel 5.9.13 (Fedora 33 x86_64) and now the mic works, no more
> > > minions voice effect. Now dmesg messages are only:
> > >
> > > kernel: usb 1-8: Warning! Unlikely big volume range (=4096), cval->res
> > > is probably wrong.
> > > kernel: usb 1-8: [3] FU [Mic Capture Volume] ch = 1, val = 0/4096/1
> > > kernel: usbcore: registered new interface driver snd-usb-audio
> > >
> > > the retire_capture_urb messages are gone.
> > >
> > > All credits for the patch go to him but I don't know how to contact
> > > that guy nor I don't know if he has already contacted you, so my
> > > question is if you could review his patch and finally apply upstream.
> > >
> > > If you need other information or you need a tester, I'm here.
> >
> > Thanks for the patch.  The still remaining warnings are about the
> > mixer, and your patch doesn't touch about it.  You may apply the
> > similar change in volume_control_quirks() like other webcams.
> >
> > And now about the patch:
> >
> > > --- a/sound/usb/format.c    2020-10-01 18:36:35.000000000 +0300
> > > +++ b/sound/usb/format.c    2020-10-04 02:10:21.678685952 +0300
> > > @@ -217,6 +217,21 @@
> > >                  (chip->usb_id == USB_ID(0x041e, 0x4064) ||
> > >                   chip->usb_id == USB_ID(0x041e, 0x4068)))
> > >                  rate = 8000;
> > > +
> > > +            // hack for "Jieli Technology USB PHY 2.0" webcam
> > > +            if (chip->usb_id == USB_ID(0x1224, 0x2a25)) {
> > > +                switch (rate) {
> > > +                case 8000:
> > > +                    fp->datainterval += 4;
> > > +                    break;
> > > +                case 16000:
> > > +                    fp->datainterval += 3;
> > > +                    break;
> > > +                default:
> > > +                    fp->datainterval += 1;
> > > +                    break;
> > > +                }
> > > +            }
> >
> > Modifying datainterval at this point doesn't look intuitive.
> > What's the original datainterval value for those altsettings?
> > The value is retrieved in snd_usb_parse_datainterval() in helper.c,
> > and if any, the correction there would be more sensible.
> >
> >
> > >              fp->rate_table[fp->nr_rates] = rate;
> > >              if (!fp->rate_min || rate < fp->rate_min)
> > > --- a/sound/usb/endpoint.c    2020-10-01 18:36:35.000000000 +0300
> > > +++ b/sound/usb/endpoint.c    2020-10-04 02:09:09.471978982 +0300
> > > @@ -882,6 +882,8 @@
> > >      if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
> > >          packs_per_ms = 8 >> ep->datainterval;
> > >          max_packs_per_urb = MAX_PACKS_HS;
> > > +        if (!packs_per_ms)
> > > +            packs_per_ms = 1;
> >
> > This rather indicates that the datainterval is somehow wrong.
> >
> > >      } else {
> > >          packs_per_ms = 1;
> > >          max_packs_per_urb = MAX_PACKS;
> > > --- a/sound/usb/quirks.c    2020-10-01 18:36:35.000000000 +0300
> > > +++ b/sound/usb/quirks.c    2020-10-04 02:14:04.532196519 +0300
> > > @@ -1516,6 +1516,7 @@
> > >      case USB_ID(0x1901, 0x0191): /* GE B850V3 CP2114 audio interface */
> > >      case USB_ID(0x21b4, 0x0081): /* AudioQuest DragonFly */
> > >      case USB_ID(0x2912, 0x30c8): /* Audioengine D1 */
> > > +    case USB_ID(0x1224, 0x2a25): /* Jieli Technology USB PHY 2.0 */
> > >          return true;
> > >      }
> >
> > This looks fine.
> >
> >
> > thanks,
> >
> > Takashi
>