Scanner is correctly identified but scan fails with "sane_start: Invalid argument" as root, and rebooting the computer sometimes makes things work, sometimes not

[Naël]

OS/Kernel: Ubuntu 12.04.5 LTS (GNU/Linux 3.2.0-80-generic x86_64)
Scanner: Epson Stylus Office BX305FW, USB 2.0, id 0x04b8/0x0863
SANE: libsane_1.0.22-7ubuntu1, libsane-common_1.0.22-7ubuntu1, sane-utils_1.0.22-7ubuntu1 (up-to-date 12.04 LTS)
Epson IScan: iscan_2.30.1-1, iscan-data_1.36.0-1 (latest versions, 2015-03-23)

The scanner is correctly identified, when logged in as root:

  # sane-find-scanner
  found USB scanner (vendor=0x04b8, product=0x0863) at libusb:001:004
  # lsusb
  Bus 001 Device 004: ID 04b8:0863 Seiko Epson Corp.
  # scanimage -L
  device `epkowa:usb:001:004' is a Epson Stylus Office BX305F/BX305FW/TX320F/ME OFFICE 620F/WorkForce 320 Series flatbed scanner

But scan fails with "scanimage: sane_start: Invalid argument" (scanimage frontend) or "Échec de la numérisation: Impossible de démarrer la numérisation" (simple-scan frontend):

  # scanimage -d epkowa:usb:001:004 -v -T
  scanimage: sane_start: Invalid argument

The permissions of the device seem nominal:

  # ls -l /dev/bus/usb/001/004
  crw-rw-r--+ 1 root lp 189, 1 avril 9 12:32 /dev/bus/usb/001/004

And the following line is present in /lib/udev/rules.d/40-iscan.rules:

  ATTRS{idVendor}=="04b8", ATTRS{idProduct}=="0863", ENV{libsane_matched}="yes"

When this problems appears, it stays so for the whole session, but rebooting the computer sometimes makes the problem go away, sometimes not. The only thing I can see that a reboot changes is the USB device ID, all the rest stays the same in the previous commands output.

For instance right now the USB device ID was 001:004 and scan wasn't working, I rebooted and it's 001:002 and scan is working. I don't know if it is relevant, I don't understand what is causing the problem, and I don't know how to investigate further.

SANE support for this scanner with external backend epkowa is normally complete, and everything runs smoothly on the reboots when the problem does not appear. Any help is appreciated. Should I report the bug upstream, or against a different package, perhaps a USB-related or boot-related one?

[Naël (nathanael-naeri)]

I forgot to mention, but when this problems appears, unplugging and replugging the scanner (or switching it off and on) does not make the problem go away, as far as I have noticed. Only rebooting sometimes make things work.

Updated SANE from 1.0.22 (-7ubuntu1) to 1.0.25 (-git20150516-precise0) using Rolf Bensch's PPA (daily git snapshots, https://launchpad.net/~rolfbensch/+archive/ubuntu/sane-git). Now scanimage also reports an epson2 scanner besides the epkowa scanner. I believe this is because support for Epson Stylus Office BX305FW has been added in backend epson2 in SANE 1.0.25, according to the lists of supported devices available on the SANE website. Epson IScan has not changed, same version as reported.

The reported behavior is still present (and still only on some boots, as reported).

[Naël (nathanael-naeri)]

Hi Christopher, thank you for resurrecting this bug report.

The affected machine has since been upgraded to Xenial. It still uses the same scanner. The current versions of sane-backends and iscan are barely more recent, so one could suppose the behavior I reported in 2015-05 could still occur. However, it hasn't manifested itself since mid-2015, or I would have moved this bug report upstream to get help.

Perhaps I've just been lucky. After all, this scanner isn't used very frequently and this bug doesn't show up every time. Still, my opinion is to close this bug as Invalid (can't reproduce). I'll re-open it in the future if necessary.

Do you still want the apport information?

OS/Kernel: Ubuntu 16.04.2 LTS (GNU/Linux 4.4.0-62-generic x86_64)
Scanner: Epson Stylus Office BX305FW, USB 2.0, id 0x04b8/0x0863
SANE: libsane, libsane-common, sane-utils version 1.0.25+git20150528-1ubuntu2 (up-to-date 16.04 LTS)
Epson IScan: iscan_2.30.3-1, iscan-data_1.39.0-1 (latest versions, 2016-12-01)

[penalvch (penalvch)]

Nathanaël Naeri (Naël), please disregard the apport-collect as it's not working for sane-backends. I've filed https://bugs.launchpad.net/ubuntu/+source/apport/+bug/1656599 to address.

Despite this, are you marking this Invalid as the issue is no longer reproducible?

[Naël (nathanael-naeri)]

Yes I am marking this Invalid because the issue hasn't manifested itself since mid-2015. See comment 3 for more details. Fingers crossed that it doesn't come back.