On Fri, Feb 07, 2020 at 03:05:31PM +0000, Brian wrote:
> On Fri 07 Feb 2020 at 09:37:17 -0500, Michael Stone wrote:
>
> > 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. :)
>
> Permisions on the USB bus are managed by an ACL.
>
> https://wiki.debian.org/Scanner
Yes, that's why I mentioned the ACL. :) But, it hasn't always been that way
and it's not the only way that will actually work...hence the other
possibilities.