On Fri, Feb 07, 2020 at 10:36:11AM +0800, kaye n wrote:
> Hello Friends!
>
> I'm running:
> Kernel: 4.19.0-6-amd64 x86_64
> bits: 64
> Desktop: Xfce 4.12.4
> Distro: Debian GNU/Linux 10 (buster)
>
> My printer is an Epson L220. It's connected to my laptop's USB port.
>
> The command lsusb shows:
> Bus 002 Device 003: ID 04b8:08d1 Seiko Epson Corp.
>
> Therefore in the file, /etc/sane.d/epkowa.conf
> I added this line:
> usb 0x04b8 0x08d1
>
> The printer can print just fine, but ImageScan and XSane would not run.
>
> ImageScan says:
> Could not send command to scanner. Check the scanner's status.
>
> XSane says:
> Failed to open device 'epkowa:usb:002:003':
> Access to resource has been denied.
>
> Thank you for your time!
This smells like a permission problem. In your example above the scanner is
on bus 002 device 003. (It may change as you unplug and replug usb devices,
so check with lsusb and change the numbers below as needed.) You can see the
permissions for that device with:
ls -l /dev/bus/usb/002/003
If it comes back with something that starts with:
crw-rw-r-- 1 root root
then it's writable only by root. A working configuration would have either
crw-rw-rw- 1 root root
or would having your username or a group that you're in rather than root, or
would look like
crw-rw-r--+ 1 root root
indicating an ACL which you can see via getfacl /dev/bus/usb/002/003
(there would be a line with your username in the default libsane
configuration).
Assuming the permissions look like they might be the problem, you can
confirm that by running
chmod o+w /dev/bus/usb/002/003
to make the file world writable (for testing only; it isn't permantent if
the scanner is unplugged or the system rebooted). If xsane works, you've
found the problem. If that's the case, the next step is probably to update
the udev configuration. If not, on to the next guess. :)