[sane-devel] Debugging sane-find-scanner/scanimage

[Rogan Dawes]

Hi folks,

I am using SANE (scanimage (sane-backends) 1.0.22; backend version
1.0.22) on OpenWRT Backfire 10.3.1 on a Buffalo WZR-HP-G300NH,
attempting to interface with a Samsung SCX4300 MFP.

This device is supported by the xerox_mfp backend, and has worked in the
past. Now, for some odd reason, it is failing to detect the scanner.

Here is the debugging output I have managed to obtain:

root at gw:/# SANE_DEBUG_XEROX_MFP=128  SANE_DEBUG_SANEI_USB=4
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.
  # Also you need support for SCSI Generic (sg) in your operating system.
  # If using Linux, try "modprobe sg".

[sanei_debug] Setting debug level of sanei_usb to 4.
[sanei_usb] sanei_usb_init: marking existing devices
[sanei_usb] sanei_usb_init: Looking for kernel scanner devices
[sanei_usb] sanei_usb_init: Looking for libusb devices
[sanei_usb] sanei_usb_init: found libusb device (0x067b/0x2303)
interface 0  at libusb:001:007
[sanei_usb] store_device: add dn 0 with libusb:001:007
[sanei_usb] sanei_usb_init: found libusb device (0x04e8/0x342e)
interface 0  at libusb:001:006
[sanei_usb] store_device: add dn 1 with libusb:001:006
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner0' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner1' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner2' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner3' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner4' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner5' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner5' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner7' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner8' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner9' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner10' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner11' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner12' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner13' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner14' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usb/scanner15' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner0' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner1' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner2' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner3' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner4' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner5' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner6' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner7' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner8' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner9' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner10' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner11' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner12' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner13' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner14' in list
[sanei_usb] sanei_usb_open: can't find device `/dev/usbscanner15' in list
found USB scanner (vendor=0x067b [Prolific Technology Inc.],
product=0x2303 [USB-Serial Controller]) at libusb:001:007
found USB scanner (vendor=0x04e8 [Samsung], product=0x342e [SCX-4300
Series]) at libusb:001:006
  # Your USB scanner was (probably) detected. It may or may not be
supported by
  # SANE. Try scanimage -L and read the backend's manpage.

  # Not checking for parallel port scanners.

  # Most Scanners connected to the parallel port or other proprietary ports
  # can't be detected by this program.
root at gw:/#


As can be seen above, sane-find-scanner identifies the USB device
representing the SCX4300.

My dll.conf contains:

root at gw:/# cat /etc/sane.d/dll.conf
xerox_mfp
root at gw:/#

And my xerox_mfp.conf contains:

root at gw:/# cat /etc/sane.d/xerox_mfp.conf
#xerox_mfp.conf

# Samsung SCX-4300
usb 0x04e8 0x342e
root at gw:/#

scanimage -L, however, fails to identify this device:

root at gw:/# SANE_DEBUG_XEROX_MFP=128  SANE_DEBUG_SANEI_USB=4 scanimage -L
[sanei_debug] Setting debug level of xerox_mfp to 128.
[xerox_mfp] sane_init: Xerox backend (build 12), version != null,
authorize != null
[sanei_debug] Setting debug level of sanei_usb to 4.
[sanei_usb] sanei_usb_init: marking existing devices
[sanei_usb] sanei_usb_init: Looking for kernel scanner devices
[sanei_usb] sanei_usb_init: Looking for libusb devices
[sanei_usb] sanei_usb_init: found libusb device (0x067b/0x2303)
interface 0  at libusb:001:007
[sanei_usb] store_device: add dn 0 with libusb:001:007
[sanei_usb] sanei_usb_init: found libusb device (0x04e8/0x342e)
interface 0  at libusb:001:006
[sanei_usb] store_device: add dn 1 with libusb:001:006
[xerox_mfp] sane_xerox_mfp_get_devices: 0x7fcb5f60, 0
[sanei_usb] sanei_usb_find_devices: vendor=0x04e8, product=0x342e
[xerox_mfp] list_one_device: libusb:001:006

No scanners were identified. If you were expecting something different,
check that the scanner is plugged in, turned on and detected by the
sane-find-scanner tool (if appropriate). Please read the documentation
which came with this software (README, FAQ, manpages).
root at gw:/#

It seems to notice the existence of the device, reporting:

[xerox_mfp] list_one_device: libusb:001:006

but it does nothing more than that.

Does anyone have suggestions as to what I can try to debug this further?

Many thanks

Rogan Dawes