usb2: scanner no longer working

[Stefan Ehmann]

On Friday 07 November 2008 17:02:47 Hans Petter Selasky wrote:
> On Friday 07 November 2008, Stefan Ehmann wrote:
> > I recompiled sane-backends and linked it against libusb20. The include
> > path needed to be fixed.
> >
> > scanimage -L doesn't detect any scanners.
> >
> > sane-find-scanner correctly detects it on first run:
> > found USB scanner (vendor=0x04a9 [Canon], product=0x221c [CanoScan],
> > chip=GL842) at libusb:/dev/usb:/dev/ugen3.2
> >
> > on subsequent runs no scanners are found
> >
> > dmesg only says
> > ugen3.2: <Canon> at usbus3
> >
> > no ugen detached message even if I unplug the scanner
> >
> > I tried some of the debugging sysctls but I couldn't spot anything
> > useful.
> >
> > ugen seems to work in general as I could access my camera with
> > libgphoto2.
> >
> > Will provide more info as needed.
>
> Hi Stefan,
>
> Which version/date is the libusb20 you are using?
The one commited to current.

> Does usbconfig list your device?
After I plug it in:
ugen3.2: <CanoScan Canon> at usbus3, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=ON

After I run scanimage or sane-find-scanner it silently disappears and usbconfig 
no longer lists it.

> Try changing ownership of the USB devices? Maybe it is a permissions
> problem.
>
> usbconfig -u xx -a xx set_owner xx:yy
I tried to run as root, so this shouldn't be the problem.