[sane-devel] Sane doesn't create a scanner device

[Henning Meier-Geinitz]

Hi,

On Thu, Oct 27, 2005 at 09:05:02AM +0200, Johannes Meixner wrote:
> For some all-in-one devices (like the Epson Stylus Photo RX420)
> which have also a cardreader unit included there is additionally
> the "usb_storage" kernel module which gets in conflict with SANE.

I don't see any difference compared to usblp. If usb_storage (or
whatever other kernel module) claims an interface different from the
scanner interface used by SANE, there should be no problem. If there
still is a problem (e.g. i/o errors), I suspect some kind of kernel bug.

> In particular for me the "ignoring EBUSY from USB" in SANE
> didn't work when both "usblp" and "usb_storage" are loaded
> but it works when only "usblp" is loaded.

What happens with usb_storage loaded? Same symptom, i.e. SANE can't
open the scanner?

> At least for me for printing and scanning "ignoring EBUSY from USB"
> is a good workaround but it seems to be not the final solution.

I think the only annoyance is the error message in syslog. On the
other hand, the kernel may be just a bit too verbose. Trying to change
the configuration while something else calims an interface is not such
a big problem which would warrant a warning message.

As we had trouble with devices which need the set_configuration
command, I want to keep it.

Bye,
  Henning