You might find that a kernel and/or a sane-backends upgrade will help that problem. There have been usb improvements in both of those places in the past year.
allan On Wed, Nov 11, 2015 at 4:49 PM, Jeremy Chacon <[email protected]> wrote: > Hi Johannes, > > Thanks for your very thorough response! > > It turned out you were correct, it was a USB issue. The scanners that always > worked were connected to USB 2.0 ports, while the scanners that gave trouble > were always connected to USB 3.0 ports (xhci_hcd when I did lsusb). > > Putting all the scanners on the older port type solved the problem. > > Thanks very much! > > Best, > > Jeremy > > On Wed, Nov 11, 2015 at 2:31 AM, Johannes Meixner <[email protected]> wrote: >> >> >> Hello, >> >> On Nov 10 14:09 Jeremy Chacon wrote (excerpt): >>> >>> ... sometimes gives an I/O Error ... >> >> >> In general "sometimes I/O Error" indicates that the root >> cause is somehow hardware related where "hardware" means >> the actual computer hardware plus the computer's built-in >> firmware (i.e. BIOS or UEFI) and "hardware related" means >> computer hardware plus firmware plus Linux kernel driver >> plus low-level hardware related software (e.g. libusb). >> You may have a look at "a stack consisting of various >> layers must be functional in its entirety" in >> https://en.opensuse.org/SDB:Configuring_Scanners#Basics >> >> You did not tell how your scanners are connected to your >> computer. >> >> If your scanners are connected via USB: >> >> There are currently issues with USB ports where the kernel >> module "xhci" is used as kernel driver. >> When "lsusb -t" shows "Driver=xhci_hcd" for the USB bus >> and port where the USB scanner is connected (see "lsusb" where >> the scanner is connected), then there could be issues depending >> on the computer hardware and firmware. >> In this case see >> https://bugzilla.opensuse.org/show_bug.cgi?id=856794 >> in particular see >> https://bugzilla.opensuse.org/show_bug.cgi?id=856794#c24 >> that reads (excerpt): >> ----------------------------------------------------------------- >> My machine has 4 USB ports, two labeled with >> the "super speed" USB logo (a.k.a. USB 3) and >> two labeled with the normal USB logo (a.k.a. USB 2) >> but for all 4 ports xhci is used and it fails on all 4 ports. >> ----------------------------------------------------------------- >> and see >> https://bugzilla.opensuse.org/show_bug.cgi?id=856794#c40 >> >> When your scanner is not connected at a USB port where the >> kernel module xhci_hcd is used as kernel driver (e.g. when >> your scanner is connected at a USB port where the kernel >> module uhci_hcd or ehci_hcd is used as kernel driver), >> then have a look at "Trouble-Shooting (Debugging)" in >> https://en.opensuse.org/SDB:Configuring_Scanners >> >> For example in your case to get USB debugging information >> you could use comands (as root) like >> ----------------------------------------------------------------- >> export SANE_DEBUG_SANEI_USB=128 >> scanimage -L >> unset SANE_DEBUG_SANEI_USB >> ----------------------------------------------------------------- >> >> >> Kind Regards >> Johannes Meixner >> -- >> SUSE LINUX GmbH - GF: Felix Imendoerffer, Jane Smithard, >> Graham Norton - HRB 21284 (AG Nuernberg) >> >> >> -- >> sane-devel mailing list: [email protected] >> http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/sane-devel >> Unsubscribe: Send mail with subject "unsubscribe your_password" >> to [email protected] > > > > > -- > ___________________________________________________________________________ > > Jeremy M. Chacon, Ph.D. > > Post-Doctoral Associate, Harcombe Lab > University of Minnesota > Ecology, Evolution and Behavior > > > -- > sane-devel mailing list: [email protected] > http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/sane-devel > Unsubscribe: Send mail with subject "unsubscribe your_password" > to [email protected] -- "well, I stand up next to a mountain- and I chop it down with the edge of my hand" -- sane-devel mailing list: [email protected] http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/sane-devel Unsubscribe: Send mail with subject "unsubscribe your_password" to [email protected]
