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 ... > allan > > On Wed, Dec 10, 2014 at 6:55 PM, Olaf Meeuwissen > <olaf.meeuwis...@avasys.jp> wrote: >> Hi Allan, >> >> m. allan noah writes: >> >>> Your patch makes no difference for the Fujitsu models in question. >>> I'll commit the patch in the next couple days, after some more >>> testing. >> >> Any progress on this? >> >>> allan >>> >>> On Mon, Dec 1, 2014 at 9:44 PM, m. allan noah <kitno...@gmail.com> wrote: >>>> Ha! As we speak, I am digging into USB3 again, because command >>>> counting seems to not fix every case. I will try your patch and report >>>> back. >>>> >>>> allan >>>> >>>> On Mon, Dec 1, 2014 at 9:21 PM, Olaf Meeuwissen >>>> <olaf.meeuwis...@avasys.jp> wrote: >>>>> Olaf Meeuwissen writes: >>>>> >>>>>> m. allan noah writes: >>>>>> >>>>>>> I have added a USB3 port to my computer, and have spent a few days >>>>>>> investigating this problem. >>>>>> >>>>>> I haven't had that kind of time, yet :-( >>>>> >>>>> Finally got time to do so. >>>>> # Someone managed to sky-rocket the priority of USB3 support to the top >>>>> # of my TODO list ;-) >>>>> >>>>>>> It seems to be a bug in Linux kernel related to a bookkeeping error >>>>>>> when the USB device is closed. [...] >>>>> >>>>> Based on two days of looking at USB3 behaviour with three EPSON scanners >>>>> and three backends, that does not seem to be the whole story. >>>>> >>>>>>> I have committed these changes to sane-backends git repo in >>>>>>> 7a590f362e7e93979b706dd9e6ae34584e926ec3. If users of fujitsu scanners >>>>>>> could try it out, I would appreciate any feedback. Note that this does >>>>>>> not fix USB3 problems in other sane backends. Until the kernel is >>>>>>> fixed, these types of repairs will have to be made on a per-backend >>>>>>> basis, at the discretion of the maintainer. >>>>> >>>>> The epson and epson2 backends have been and still are using the kind of >>>>> command counting and making sure to send an even count of reads and >>>>> writes you added to the fujitsu backend. That notwithstanding, they >>>>> suffer from USB3 I/O problems with the Perfection V700 (GT-X900) and >>>>> ES-H300 (GT-2500). The epkowa backend does *not* even up the reads and >>>>> writes and unsurprisingly shows the same problems. In addition, the >>>>> GT-D1000 (GT-1500), a non-free plugin needing device, is also affected. >>>>> >>>>> Making the epkowa backend even up the reads and writes did *not* fix the >>>>> problem. What did fix the problem for all three scanners and all three >>>>> backends for me was a tiny change in sanei_usb.c. With that change, the >>>>> evening up of reads and writes was not needed either. >>>>> >>>>> The sanei_usb.c code unconditionally sets the USB configuration. This >>>>> happens even if the device has only one. I found that *not* setting the >>>>> USB configuration when there is only one fixed all my USB3 problems. My >>>>> understanding of the USB2 and USB3 standards is that the default USB >>>>> configuration has to be set before devices become available to libusb. >>>>> If that understanding is correct, then there is no need to set it unless >>>>> you need a configuration that *differs* from the current one. With only >>>>> one configuration to choose from, there is then no need to set it. >>>>> >>>>> This patch does exactly that. It skips setting the USB configuration if >>>>> there is only one. It should not break USB for any of the backends and >>>>> *may* fix USB3 for all of them. >>>>> >>>>> Note: it may still set the default configuration if there are multiple >>>>> ones to choose from. I have no devices I can test with to see if >>>>> that is problematic or not. Even so, modifying the code to only >>>>> set a USB configuration if it differs should be safe. >>>>> # Patch is in preparation. >>>>> >>>>> Allan, can you locally revert your fujitsu fixes and try with the patch >>>>> I applied? Does that fix your USB3 issues? Do you still need to even >>>>> up the reads and writes? >>>>> >>>>> Unless it breaks things for you, could you please commit my patch? >>>>> # Even if it does not fix USB3 for you. >>>>> >>>>> Other people with USB3 issues are of course more than welcome to try >>>>> this patch too! >>>>> >>>>>> [...] >> >> Hope this helps, >> -- >> Olaf Meeuwissen, LPIC-2 FLOSS Engineer -- AVASYS CORPORATION >> FSF Associate Member #1962 Help support software freedom >> http://www.fsf.org/jf?referrer=1962 -- Olaf Meeuwissen, LPIC-2 FLOSS Engineer -- AVASYS CORPORATION FSF Associate Member #1962 Help support software freedom http://www.fsf.org/jf?referrer=1962 -- sane-devel mailing list: sane-devel@lists.alioth.debian.org http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/sane-devel Unsubscribe: Send mail with subject "unsubscribe your_password" to sane-devel-requ...@lists.alioth.debian.org
