[LAU] Repeated USB error/warning notification

Chris Caudle chris at chriscaudle.org
Tue May 22 19:40:54 CEST 2018

On Tue, May 22, 2018 12:21 pm, Chris Caudle wrote:
> On Tue, May 22, 2018 11:40 am, Jeanette C. wrote:
>> [1354175.824801] usb 1-4.1: urb status -32

> This is the list of status codes returned, but they are symbolic, I have
> not  found where the numeric values are mapped to the symbolic names:
> https://www.kernel.org/doc/html/v4.12/driver-api/usb/error-codes.html

I cannot find the header with the error codes in that previous web reference.
I did find in usbdevice_fs.h this URB status code.  Hex 0x20 would
correspond to 32 if the original status code is printed in decimal.

#define USBDEVFS_URB_NO_FSBR            0x20    /* Not used */

That "not used" note is odd, I don't know if that means the comments in
that file are out of date, or if the original console message is not
determined from usbdevice_fs.h

Is this only during startup?  I found emails about FSBR going back to the
2.6 kernel version where there was some feature turned off during
enumeration until all the devices were discovered and configured, and then
if it was appropriate for the device the feature was turned back on.

If that reference applies to the message you saw, if it only is displayed
during startup or when a new device is connected, and it does not cause
other errors, I suspect it is just an information message left over from
that old change.  I  am not familiar enough with USB device enumeration to
know what the feature is, but I suspect the "FS" refers to full speed,
referring to determining in a device is low speed, full speed, or high
speed during enumeration.

Chris Caudle

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