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USB Bandwith issue on IMX8M Mini

Question asked by Tyler Ward on Aug 1, 2019
Latest reply on Aug 6, 2019 by Tyler Ward

I am encountering an issue using a USB sound card based on the cmedia CM6206 IC when used on the IMX8M Mini dev board running the example yocto build with some additional packages. When used on the IMX board i get the following dmesg errors indicating a lack of usb bandwidth.  

 

[ 7842.124001] retire_capture_urb: 1242 callbacks suppressed
[ 7847.126543] retire_capture_urb: 1241 callbacks suppressed
[ 7852.129241] retire_capture_urb: 1240 callbacks suppressed
[ 8131.025107] kauditd_printk_skb: 313 callbacks suppressed
[ 8131.025113] audit: type=1006 audit(1564672351.145:9): pid=4524 uid=0 old-auid=4294967295 auid=0 tty=(none) old-ses=4294967295 ses=8 res=1
[ 8468.600276] retire_capture_urb: 1231 callbacks suppressed
[ 8491.603052] usb 1-1: cannot submit urb 0, error -28: not enough bandwidth
[ 8504.029087] retire_capture_urb: 586 callbacks suppressed
[ 8509.034814] retire_capture_urb: 1231 callbacks suppressed
[ 8514.042949] retire_capture_urb: 1242 callbacks suppressed
[ 8519.050003] retire_capture_urb: 1242 callbacks suppressed
[ 9180.893566] kauditd_printk_skb: 741 callbacks suppressed

The suppressed callbacks and not enough bandwidth errors are from different test applications. I have tested on other boards (an Intel based up board and an arm based odroid c2) and I don't get the errors shown above. Have other people encountered this issue and is there a solution for this problem?

 

Thanks

Tyler

 

Some additional information:

root@imx8mmevk:~# lsusb -t
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ci_hdrc/1p, 480M
|__ Port 1: Dev 6, If 0, Class=Audio, Driver=snd-usb-audio, 12M
|__ Port 1: Dev 6, If 1, Class=Audio, Driver=snd-usb-audio, 12M
|__ Port 1: Dev 6, If 2, Class=Audio, Driver=snd-usb-audio, 12M
|__ Port 1: Dev 6, If 3, Class=Human Interface Device, Driver=usbhid, 12M

This one works

arecord -D hw:1,0 -f S16_LE -c 2 -r 48000 | aplay -D hw:1,0 -f S16_LE -c 2 -r 48000

This one does not

arecord -D hw:1,0 -f S16_LE -c 2 -r 48000 | aplay -D hw:1,0 -f S16_LE -c 4 -r 48000

Outcomes