[sane-devel] Dell MFP S2815dn/H815dw support?

[Carl-Daniel Hailfinger]

Hello everyone,

I own a Dell MFP S2815dn which is almost identical to the Dell MFP
H815dw. The printer/scanner/copier/fax is probably built by Fuji Xerox
(its MAC address is from Fuji Xerox).
According to the manual of the scanner, scanning can be controlled by
local console (e.g. scan-to-email), via USB and via network.

Adding the USB ID to /etc/sane.d/xerox_mfp.conf of the sane-xerox_mfp
backend of sane-backends version 1.0.26-git20160712 (Ubuntu 14.04
x86_64, rolfbensch PPA) didn't help, and when enabling debugging I can
see the SENSE command doesn't get an answer. This happens regardless of
whether I run it as root or as user. That might be a collision with
other usb drivers binding to the device, but even when blacklisting
usblp and checking that no other drivers are bound to the USB device,
scanimage -L doesn't find the scanner.
sane-find-scanner claims that it found three USB scanners, but I only
have one scanner attached. The other two "matches" are my USB bluetooth
adapter and my USB fingerprint reader.

What would be a good way to get the Dell S2815 supported?
lsusb? Logs? What's the preferred log level?
I'm willing to try patches, and I could even try to get a USB trace from
the windows driver if I manage to find a Windows VM somewhere.

On a slightly related note: How can I eliminate the false positives from
sane-find-scanner?

Regards,
Carl-Daniel