[sane-devel] Scanner 'reset scan head' utilities (plustek, Canon Lide20)

[Gerhard Jaeger]

On Montag, 25. Juni 2007, Jeff Kowalczyk wrote:
> Jeff Kowalczyk wrote:
> > My everyday flatbed scanner ((vendor=0x04a9 [Canon], product=0x220d
> > [CanoScan], chip=LM9832/3) at libusb:002:002) got out of sorts today.
> > The scan head wasn't returned to the home position (it is now), but
> > XSane scans now just return solid black data.
> 
> I see that it's a known problem, since I have (recently) enabled
> CONFIG_USB_SUSPEND to try powertop, and this is using the plustek backend.
> 
In fact it's not only a Plustek problem - it's a problem of all ASICs, that
support someting like a suspend mode. The LM983x enters that mode, when there
is no activity on the USB-bus for 3ms. Most of the registers will be reset
during that...

I will try and focus on that during the next days...

Cheers
Gerhard