Re: usb2: scanner no longer working

On Friday 07 November 2008, Stefan Ehmann wrote:
> 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
>

Hi,

If usbconfig does not list your device, then it is no longer present in the 
system.

Are you running USB2 on a 64-bit architecture?

Try again having HUB debugging turned on.

sysctl hw.usb2.uhub.debug=15

I suspect that your device:

a) had firmware loaded and the scanner driver called the device reset 
function, which is a little different than on linux.

b) USB firmware crashed. Maybe your device needs a quirk?

--HPS