Hello,

I recently bought a SANE-supported USB document scanner (Fujitsu
S1300i), in the hope of using it on my OpenBSD desktop. After a bit of
murking around with firmware blobs, I eventually managed to make it work
once. At that is where I'm stuck.

To put it more precisely, after turning on the device, I get exactly
once successful use of `scanimage`, and only timeouts afterwards.

At first I thought of an issue with not sending the firmware blob, but
then I wrote a culled-down use of libusb which only queries the device
status, and I get the same symptoms: status is read fine on the first
try after powering the device, and then only read timeouts (but the
command-writing part is still successful).

Here is the code in question:
https://upload.instinctive.eu/5DpBeF32WUvs1f2Yc3TC34fbz38/test-usb.c
(sorry for the lazy style)

It is probably worth pointing that the exact same code, compiled on
linux with the same libusb version, and the exact same device, manages
to query repeatedly the device status both before and after sending the
frimware blob.

So I belive there is a bug somewhere in libusb port or in OpenBSD USB
stack. My guess would be something that is not correctly cleaned-up
after the first use.

Since you all probably don't have the device, I don't expect a fix, but
I would be very interested in what I can do to further diagnose the
issue. I guess it would be nice to spy on what is going on in the USB
wire, but I don't have that kind of hardware. So I was hoping you could
help me navigate the USB stack to dump useful information.

I have some dumps from libusb-debug, but I cannot find anything useful
here, both runs are identical until the timeout. Maybe you can spot
something more?
https://upload.instinctive.eu/a6TAzULS9R6k82g_U9go4XjmDAo/libusb-debug-first.txt
https://upload.instinctive.eu/kn7VfrcHo1FLaDuU_Lk4L8FqhNI/libusb-debug-second.txt

In case it matters, I'm running CURRENT, with `what /bsd` printing
OpenBSD 6.6-current (GENERIC.MP) #643: Tue Feb 11 00:08:34 MST 2020

Any ideas?


Thanks in advance for your help,
Natasha

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