[sane-devel] Re: scanner Epson DX4250 not working in Ubuntu 11.10

[Olaf Meeuwissen]

Hi Giorgio,

Sorry for the belated follow-up.  I'm just about as puzzled as you but
please find my thinking-out-loud comments in-lined below.

"Giorgio F. Signorini" <giorgio.signorini at unifi.it> writes:

> Maybe I should point out here that the same scanner (with the same USB
> cable!) works well on my laptop: Ubuntu 10.10, with
>     xsane: 0.997-2ubuntu3
>     libsane: 1.0.21-2ubuntu2

That rules out any hardware problems with the scanner.

> Problems arise only with my desktop: Ubuntu 11.10, with
>     xsane: 0.998-3ubuntu1
>     libsane: 1.0.22-2ubuntu2

Could be caused by changed package versions or different computer
hardware.

> The same happens to other users
> [see https://bugs.launchpad.net/simple-scan/+bug/888267]

Hmm, keeping working Simple Scan and libsane packages from 11.04 and
upgrading the rest of one's system to 11.10 breaks things ...  Looks
like something else is throwing a spanner in the (USB) works.

> From what you say I suspect that the problem might be in the USB
> management
>
> ** ubuntu 10.10 **
> libusb-0.1-4 -> 2:0.1.12-15ubuntu2
> libusbmuxd1  -> 1.0.4-1
> libusb-1.0-0 -> 2:1.0.8-2
>
> ** Ubuntu 11.10 **
> libusb-0.1-4 -> 2:0.1.12-18
> libusbmuxd1  -> 1.0.7-1ubuntu0.11.10.1
> libusb-1.0-0 ->  2:1.0.8-4
>
> Would it be useful/possible/advisable to downgrade these?

Changing the libusb-* packages is unlikely to make a difference.  Not
quite sure how USB multiplexing might play a role here, but you could
try turning off usbmuxd (if it's running) to see if that helps before
downgrading.

Another option is upgrading to 12.04.

A truly long shot for the epkowa backend that came with iscan, and only
really worth trying if the usblp kernel module is loaded (see `lsmod |
grep usblp`), is to

  export SANEI_USB_KEEP_USBLP=1

before starting your SANE frontend of choice.  Just make sure to use
the epkowa backend as the epson2 (and deprecated epson) backends will
not pay attention to this environment variable.

Hope this helps,
-- 
Olaf Meeuwissen, LPIC-2           FLOSS Engineer -- AVASYS CORPORATION
FSF Associate Member #1962               Help support software freedom
                 http://www.fsf.org/jf?referrer=1962