[cups.bugs] [MOD] STR #3964: On some printers the libusb-based "usb" CUPS backend needs to send a reset signal to the printer

Till Kamppeter till.kamppeter at gmail.com
Thu Oct 20 03:15:05 PDT 2011


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[STR New]

Attached is a patch for backend/usb-libusb.c. It makes a printer reset,
equivalent to the small C program which I attached in the beginning (I
checked the source code of libusb) before each job. After the reset I
close the device and reinitialize the connection (simple reopen does not
work), as otherwise some printers (I tested with 5 different HP printers)
crash and reboot and/or drop the job.

Now all printers print reliably and one does not perceive any additional
delay between jobs.

I am applying the patch to the Ubuntu package of CUPS and let the original
bug reporter test whether it solves his problem.

Note that the patch is set up to get a quick testing and can perhaps be
done in a more elegant way by someone who is more knowledgeable about USB
than me.

Link: http://www.cups.org/str.php?L3964
Version: 1.5.0





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