On Wed, 24 Mar 2021 13:03:14 +0100, Ikjoon Jang wrote: > > On Wed, Mar 24, 2021, 7:16 PM Joakim Tjernlund <Joakim.Tjernlund@xxxxxxxxxxxx> > wrote: > > On Wed, 2021-03-24 at 18:51 +0800, Ikjoon Jang wrote: > > Logitech ConferenceCam Connect is a compound USB device with UVC and > > UAC. Not 100% reproducible but sometimes it keeps responding STALL to > > every control transfer once it receives get_freq request. > > > > This patch adds 046d:0x084c to a snd_usb_get_sample_rate_quirk list. > > > > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203419 > > Signed-off-by: Ikjoon Jang <ikjn@xxxxxxxxxxxx> > > Most Logitech USB headset I got needs a delay in snd_usb_ctl_msg_quirk() > Have you tried to add say 20 ms delay in there? > > I didn't try that. But it sounds reasonable to me. > > let me try that quirk here. If that is the case, HID might need that delay > also. Logitech Group webcam had a similar problem on control xfer of > get_report from an another interface for HID. The Logitech devices with 046d:* should be covered generally in snd_usb_ctl_msg_quirk(), so I guess it's a different problem. But please check it first. > And 20ms can be too long if it's applied to every control transfer. I will > test the device with shorter delay if you didn't try it before. Actually the delay applied to Logitech devices is from 1 to 2ms, not 20ms. The 20ms delay is applied for some other devices. But if extending the delay fixes the problem, we need to reconsider the delay length. Takashi
