2003-09-08 12:21:12

by Ian Stirling

[permalink] [raw]
Subject: USB error numbers

Where do the various numbers come from in messages such as
USB device not accepting new address=5 (error=-110), and what do they
"mean"?
I'm trying to work out why this happens when I plug in one of several
webcams (into any of several computers) and one webcam occasionally.


2003-09-08 15:29:19

by Randy.Dunlap

[permalink] [raw]
Subject: Re: USB error numbers

> Where do the various numbers come from in messages such as
> USB device not accepting new address=5 (error=-110), and what do they
> "mean"?
> I'm trying to work out why this happens when I plug in one of several
> webcams (into any of several computers) and one webcam occasionally. -

Hm, the USB error numbers are listed/documented in
linux/Documentation/usb/error-codes.txt (by name).

Look in include/<asm-arch>/errno.h to match names to values
(or include/asm-generic/errno.h).

-110 for x86 is -ETIMEDOUT (USB returns negative error numbers).
It can mean that the device just wasn't responding, or it can mean
that there is a problem with USB interrupt routing. There is lots
of work going on in this area right now, especially related to ACPI
interrupt routing.

~Randy