[sane-devel] sane to work with USB 3.0

[Gerhard Jäger]

Allan,

you're da man ;)

I've just pulled the updated sources, built and installed. Plugged in my
CanoScan LiDE30 (plustek-backend) to a USB 3 port:

usb 3-1: USB disconnect, device number 2
usb 3-1: new full-speed USB device number 3 using xhci_hcd
usb 3-1: New USB device found, idVendor=04a9, idProduct=220e
usb 3-1: New USB device strings: Mfr=64, Product=77, SerialNumber=0
usb 3-1: Product: CanoScan
usb 3-1: Manufacturer: Canon

And it seems to fix the issues that have been observed with the plustek
backend.

Thanks for taking care,
  Gerhard


On Tuesday 16 December 2014 10:33:14 m. allan noah wrote:
> I have just committed an attempted workaround for this Linux kernel
> bug. I have tested with Fujitsu and Canon scanners, and it does fix
> the problem. I have not tested with other scanners. We need as much
> testing on this as we can get. Please build from a current git
> checkout (or tomorrow's git snapshot), and let us know what you find.
> 
> allan
> 
> On Thu, Dec 11, 2014 at 9:05 PM, m. allan noah <kitno455 at gmail.com> wrote:
> > On Thu, Dec 11, 2014 at 2:21 AM, Olaf Meeuwissen
> > 
> > <olaf.meeuwissen at avasys.jp> wrote:
> >> m. allan noah writes:
> >>> I have just pushed your patches to git. They don't seem to help with
> >>> any scanner that I have, but I doubt they will hurt anything.
> >> 
> >> Thanks!
> >> 
> >>> It appears that we also have USB3 issues with Canon scanners as well-
> >>> they do use clear_halt frequently, and it seems that maybe the Linux
> >>> kernel is not passing them down to the scanner in some cases.
> >> 
> >> Do they halt/stall that frequently?  If there's no stall, clear_halt
> >> should not be used, IIUC.  Hmm, it doesn't look like sanei_usb allows
> >> you to find out about that ...
> > 
> > Yeah, the Canon machines halt at the drop of a hat. I added
> > sanei_usb_clear_halt specifically for them.
> > 
> > But, no matter. Based on the threads linked from this post:
> > http://www.spinics.net/lists/linux-usb/msg105515.html I have come up
> > with a workaround that fixes both the Canon and the Fujitsu machines I
> > have access to. It seems the xhci controller refuses to transmit a
> > clear_halt to the device or reset the data 0/1 toggle in the host when
> > the ehci controller would. However, sending a set_interface command
> > for the interface that is already selected, seems to do both of those
> > things. So, I added a call to
> > 
> > sanei_usb_set_altinterface (s->fd, 0);
> > 
> > right before the calls to sanei_usb_close() or sanei_usb_clear_halt()
> > in those two backends, and everything suddenly seems to work.
> > 
> > I need to do some further testing, and see if these changes should be
> > moved up to sanei_usb instead of the backends.
> > 
> > allan
> > --
> > "well, I stand up next to a mountain- and I chop it down with the edge
> > of my hand"