Bug 213897

Summary: [Regression] 62ecbb00e3128d718ae breaks USB sound dongle
Product: Drivers Reporter: Martin Demlon (m)
Component: Sound(ALSA)Assignee: Jaroslav Kysela (perex)
Severity: normal CC: tiwai
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 5.13.4 Subsystem:
Regression: No Bisected commit-id:
Attachments: Test fix
alsa-info output with the iMic device plugged in

Description Martin Demlon 2021-07-28 17:51:09 UTC
Going from Kernel 5.11.7 to 5.13.0, my USB sound dongle (idVendor=077d, idProduct=07af, bcdDevice= 0.06; Product: iMic USB audio system, Manufacturer: Griffin Technology, Inc) stopped outputting audio; the microphone input kept working.

On plugging in, the new kernel gives the following error messages:

  kernel: usb 2-1: cannot get connectors status: req = 0x81, wValue = 0x900, wIndex = 0x100, type = 0
  kernel: snd-usb-audio 2-1:1.0: reset_resume error -22
  kernel: usb 2-1: 1:0: usb_set_interface failed (-71)

repeating the last line another five times.

The device has worked in earlier kernels for something like a decade, though a while ago the kernel started to complain that

  kernel: usb 2-1: Warning! Unlikely big volume range (=656), cval->res is probably wrong.

which I kept ignoring because it didn't seem to result in operational trouble.

Going through the commits that changed the sound/usb/mixer.c file that the connectors status message comes from, I found commit 44609fc01f280d6b4067262ecbb00e3128d718ae.  Undoing that commit fixes the dongle.  

I admit I've not tried to identify where things actually break and how the Griffin dongle can be saved without breaking again whatever that commit fixed.  If that's not obvious to people who actually understand this code, I'm happy to research further, though.jj
Comment 1 Takashi Iwai 2021-07-29 06:10:00 UTC
Could you give alsa-info.sh output?  Run the script with --no-upload option and attach to Bugzilla.
Comment 2 Takashi Iwai 2021-07-29 06:23:06 UTC
Also, could you try the patch below?
Comment 3 Takashi Iwai 2021-07-29 06:23:32 UTC
Created attachment 298099 [details]
Test fix
Comment 4 Martin Demlon 2021-07-29 16:56:47 UTC
The patch works nicely for me -- thanks!

I'll still attach the alsa info in case it helps understanding why it works :-)
Comment 5 Martin Demlon 2021-07-29 16:57:54 UTC
Created attachment 298109 [details]
alsa-info output with the iMic device plugged in
Comment 6 Takashi Iwai 2021-10-05 13:49:21 UTC
The fix has been already in the upstream.  Let's close.