[sane-devel] re epson perfection 1200 problems libusb kernel 2.6.1-rc1

[Henning Meier-Geinitz]

Hi,

On Sat, Jan 17, 2004 at 02:15:08PM +0000, Jim Quigley wrote:
> Klaus Dittrich wrote:
> 
> >Is your machine smp  ?
> >Do you have preemptive syscalls enabeld ?
> >Do you use linuxthreads or nptl ?

I don't think that linuxthreads or nptl is involved as by default SANE
uses processes (fork), not threads.

>Hi Don't know what 'smp'

SMP: Symmetric MultiProcessing = more than one processor. 

> or linuxthreads' 'nptl' are

These are two different ways of using threads.

> but I did compile the kernel with preemptive kernel.

I suspect that this may be a possible reason for your problems. Also
SMP may be a reason. I'll now try 2.6 with some of these options
enabled.

> scanimage -d epson:libusb:003:002 --test scanimage: scanning image of 
> size 424x584 pixels at 1 bits/pixel
> scanimage: acquiring gray frame, 1 bits/sample
> scanimage: reading one scanline, 53 bytes...
> FAIL Error: Error during device I/O[epson] option: fatal error

The kernel messages that occur when the scan fails for the first time
may be important (e.g. in /var/log/messages).

> I also had tried before loading scanner.o driver and that worked when I 
> used 'modprobe scanner' but I then had problems with epson printer usblp 
> and hotplug could not unload the module when closing down. I now have 
> printer compiled into the kernel not as a module and I did not choose 
> the scanner module which it says is obsolete.

The scanner module should also work but may have the same problems as
libusb with SMP and/or preemptible kernel.

Bye,
  Henning