Happy New Year Folks smile
I have a Netgear DGN3500 running CHAOS CALMER (15.05, r46767)
I cannot have my 'usb webcam' and 'usb sound card' working
The problem seems to be the missing support for 'usb isochronous transfer'


Webcam: Creative WebCam Instant

Plugging in; kernel log:

[  819.364000] usb 1-1: new full-speed USB device number 2 using ifxusb_hcd
[  819.580000] gspca_main: gspca_zc3xx-2.14.0 probing 041e:4034
[  819.832000] input: gspca_zc3xx as /devices/platform/ifxusb_hcd/usb1/1-1/input/input0

The kernel modules seem to be installed and working fine, file '/dev/video0' shows up.
When I call 'fswebcam', it fails with errors; kernel log:

[ 3374.996000] gspca_zc3xx 1-1:1.0: URB error -150, resubmitting
[ 3374.996000] gspca_main: Resubmit URB failed with error -2
[ 3376.356000] IFXUSB: ISOC transfer not supported!!!
[ 3376.372000] gspca_main: usb_submit_urb alt 5 err -19

Sound Card: 'C-Media Electronics CM106'

Plugging in; kernel log:

[ 4498.444000] usb 1-1: new full-speed USB device number 3 using ifxusb_hcd
[ 4498.724000] usb 1-1: current rate 30464 is different from the runtime rate 96000
[ 4498.764000] usb 1-1: Warning! Unlikely big volume range (=8065), cval->res is probably wrong.
[ 4498.772000] usb 1-1: [9] FU [Mic Playback Volume] ch = 2, val = -6144/1921/1
[ 4498.804000] usb 1-1: Warning! Unlikely big volume range (=8065), cval->res is probably wrong.
[ 4498.808000] usb 1-1: [11] FU [Line Playback Volume] ch = 2, val = -6144/1921/1
[ 4498.880000] usb 1-1: Warning! Unlikely big volume range (=6928), cval->res is probably wrong.
[ 4498.884000] usb 1-1: [8] FU [Mic Capture Volume] ch = 2, val = -4096/2832/1
[ 4498.916000] usb 1-1: Warning! Unlikely big volume range (=6928), cval->res is probably wrong.
[ 4498.924000] usb 1-1: [15] FU [Line Capture Volume] ch = 2, val = -4096/2832/1
[ 4498.956000] usb 1-1: Warning! Unlikely big volume range (=6928), cval->res is probably wrong.
[ 4498.960000] usb 1-1: [2] FU [PCM Capture Volume] ch = 2, val = -4096/2832/1

I know it looks a bit of a mess, but I get the same warning messages in pc, where the card works fine.
Kernel modules should be all right; files /dev/audio, /dev/dsp and /dev/mixer show up.
When I call 'madplay', it fails with errors; kernel log:

[ 4570.824000] IFXUSB: ISOC transfer not supported!!!
[ 4570.828000] usb 1-1: cannot submit urb 0, error -19: no device

Conclusion

I though my two old pieces of hardware were the problem, requesting an obsolete standard.
I was considering buying new ones but making a research I found out that isochronous transfer still today is meant to be used for video and audio stream:
USB in a NutShell - Chapter 4 - Endpoint Types

There is very little talk online about isochronous transfer support, even less in the OpenWrt scenario.
Any help will be highly appreciated
Cheers

(Last edited by claudio on 3 Jan 2018, 12:28)