Recently I updated my Fedora 19 system and all appeared to be well until I wanted to quickly scan in a document to send to a colleague. The scanner I used is my old trustly Canon LiDE 30. Simple-scan refused to work because it claimed that no scanners were detected.
Using lsusb, I quickly determined that the scanner was detected:
# lsusb Bus 002 Device 004: ID 045e:076c Microsoft Corp. Comfort Mouse 4500 Bus 002 Device 003: ID 045e:0734 Microsoft Corp. Wireless Optical Desktop 700 Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 003: ID 04a9:220e Canon, Inc. CanoScan N1240U/LiDE 30 Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Next step was to use sane-find-scanner and scanimage -L respectively:
# sane-find-scanner # sane-find-scanner will now attempt to detect your scanner. If the # result is different from what you expected, first make sure your # scanner is powered up and properly connected to your computer. # No SCSI scanners found. If you expected something different, make sure that # you have loaded a kernel SCSI driver for your SCSI adapter. could not fetch string descriptor: Pipe error could not fetch string descriptor: Pipe error could not fetch string descriptor: Pipe error could not fetch string descriptor: Pipe error found USB scanner (vendor=0x04a9 [Canon], product=0x220e [CanoScan]) at libusb:001:003 .... # # scanimage -L device `plustek:libusb:001:003' is a Canon CanoScan N1240U/LiDE30 flatbed scanner
OK, all is as expected so far. So what was going on? A quick Internet search suggested that I should check for /dev/usbscanner and for entries under /proc/bus/usb. Turns out that Fedora 19 has neither.
On a hunch I examined /var/log/yum.log to check when SANE (Scanner Access Now Easy) packages were last updated.
Oct 20 13:25:52 Updated: sane-backends-libs-1.0.24-2.fc19.x86_64 Oct 20 13:25:54 Updated: sane-backends-1.0.24-2.fc19.x86_64 Oct 20 13:26:06 Updated: sane-backends-drivers-scanners-1.0.24-2.fc19.x86_64 Oct 20 13:26:07 Updated: sane-backends-drivers-cameras-1.0.24-2.fc19.x86_64 Oct 20 13:26:40 Updated: sane-backends-devel-1.0.24-2.fc19.x86_64 Oct 20 13:27:25 Updated: sane-backends-doc-1.0.24-2.fc19.noarch
Since I was in a hurry, I decided to downgrade a number of these packages
# yum downgrade sane-backends-libs sane-backends sane-backends-drivers-scanners # grep "Oct 20 01:46" /var/log/yum.log Oct 22 01:46:21 Installed: sane-backends-libs-1.0.23-18.fc19.x86_64 Oct 22 01:46:22 Installed: sane-backends-1.0.23-18.fc19.x86_64 Oct 22 01:46:23 Installed: sane-backends-drivers-scanners-1.0.23-18.fc19.x86_64 #
Turns out my hunch was correct. Downgrading these packages fixed my problem and simple-scan was able to see the attached scanner.
Moral of the story: Sometimes it is quicker to downgrade a package or two to fix your immediate problem.