Re: usb2: scanner no longer working

On Thursday 13 November 2008 16:57:55 Hans Petter Selasky wrote:
> On Thursday 13 November 2008, Stefan Ehmann wrote:
> > On Friday 07 November 2008 19:35:17 Hans Petter Selasky wrote:
> > > On Friday 07 November 2008, Stefan Ehmann wrote:
> > > > On Friday 07 November 2008 18:42:49 Hans Petter Selasky wrote:
> > > > > On Friday 07 November 2008, Hans Petter Selasky wrote:
> > > > > > Hi,
> > > > > >
> > > > > > Could you dump the current config descriptor of your scanner?
> > > > > >
> > > > > > usbconfig -u 3 -a 2 dump_curr_config_desc
> > > >
> > > > # usbconfig -u 3 -a 2 dump_curr_config_desc
> >
> > <snip>
> >
> > > > > 3 and 2 are the numbers after ugen, like ugen3.2
> > > >
> > > > To your other mail:
> > > > I'm running i386. HUB debugging didn't output any obvious errors.
> > >
> > > Hi,
> > >
> > > Try the following patch to libusb20. I suspect that it is the
> > > set_configuration call that makes trouble!
> > >
> > > http://perforce.freebsd.org/chv.cgi?CH=152628
> > >
> > > Thanks for reporting.
> > >
> > > My private SVN repository has also been updated to include this patch
> > > if you are using that.
> >
> > As I previously stated in my other mails. The scanner is now properly
> > recognized.
> >
> > Now I got this problem:
> > Before scanning starts, the system "locks" for several minutes, i.e.
> >  - input/output to terminals is no longer working
> >  - I can still switch consoles and break into ddb
> >  - CTRL-t on the scanimage console is still working and shows increasing
> > sys time
> >
> > As soon as the actual scanning process starts, everything is fine again.
> > Sometimes scanning doesn't start at all (or I'm just not patient enough).
> >
> > To make debugging a bit more interesting: If I run scanimage with ktrace
> > or enable usb debugging via sysctl, scanning starts immediately. Don't
> > know if this is always the case but seemed to work a few times at least.
> > So maybe it's some kind of timing problem.
>
> Strange!
>
> Try this before starting your scanimage:
>
> sysctl hw.usb2.ugen.debug=15
>
> I guess that the program is looping on a poll-syscall, because I poll on
> both stdin and the I/O descriptor. This is perhaps another bug in libusb20.

I've compared debug output of a scan without delay and one with delay. 
Couldn't spot anything obvious. I can post the complete logs if you're 
interested.

Here's the snippet where it hangs (look at the timestamps)

Nov 13 17:15:07 something kernel: ugen_ioctl:2194: cmd=800155c0
Nov 13 17:15:07 something kernel: ugen_ioctl:2205: error=0
Nov 13 17:15:07 something kernel: ugen_ioctl:2194: cmd=400155c2
Nov 13 17:15:07 something kernel: ugen_ioctl:2205: error=16
Nov 13 17:20:01 something kernel: ugen_default_fs_callback:2215: st=0 alen=0 
afr
ames=0
Nov 13 17:20:01 something kernel: ugen_default_fs_callback:2215: st=1 
alen=16384
 aframes=1
Nov 13 17:20:01 something kernel: ugen_ioctl:2194: cmd=400155c2
Nov 13 17:20:01 something kernel: ugen_ioctl:2205: error=0