Nothing Prints. Problem with /dev/parport0
 

I'm having trouble getting **anything** to print after building a new AMD64 system with Gentoo Linux. Even low level commands such as

"#cat test.txt > /dev/lp0" causes the LED on my laser printer to blink a little, but nothing prints.

The same command to the parport0 device
"#cat test.txt > /dev/parport0" bombs with
"cat: write error: Invalid argument"


If I do a "ls -la" to the /dev directory, I can see the character device "/dev/parport0". Also, "/dev/lp0" points to "/dev/printers/0".

Running the same commands from SuSE 9.2 works just fine, so I'm sure there are no true hardware problems with my system. I'm logged in as root, so permissions should not be an issue.

I've got every bloody parallel port module loaded that I can find. lsmod shows:
Module Size Used by
ppdev 8200 0
lp 11256 0
parport_pc 29672 1
parport 35852 3 ppdev,lp,parport_pc




dmesg shows the parallel port is up and running (it even recognizes my Samsung laser printer):
parport_pc: Ignoring new-style parameters in presence of obsolete ones
parport: PnPBIOS parport detected.
parport0: PC-style at 0x378 (0x778), irq 7, dma 3 [PCSPP,TRISTATE,COMPAT,EPP,ECP,DMA]
parport0: Printer, Samsung ML-1450
lp0: using parport0 (interrupt-driven).
lp0: console ready
lp0: ECP mode
ppdev: user-space parallel port driver
lp0: ECP mode
ppdev0: claim the port first
ppdev0: claim the port first
lp0: ECP mode



If I try to print (from CUPS, the command line, or whatever), the activity LED on my laser printer flashes slowly, but **never** stops, and never prints. (My guess is that nothing actually is getting through the port.)


I'm guessing that somehow the handshaking starts on the parallel port, but no data is actually traversing the port.

I've tried compiling the parallel port drivers into the kernel (2.6.10), or as modules. Neither seems to make much difference.


Anybody have any suggestions for things to try to troubleshoot this problem?

"Anybody have any suggestions for things to try to troubleshoot this problem?"

Another possibility is that the print spool may have garbage gunking up the works. Take a look at /var/spool/cups and /var/spool/lpd and see if you are accumulating all of your unsuccessful print attempts on the spool. If so delete all of the files (but not the tmp directory) on the two spools and try again.

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Steve Stites

I've got the same problem. Did you ever solve this problem ?

No. I do suspect a problem with the parport_pc module, however. In my dmesg file there is this funny comment:

"parport_pc: Ignoring new-style parameters in presence of obsolete ones"


One of my attempted fixes was to pass along the "irq=none" parameter on the module line. This parameter appears to have been ignored, and I get this weird, cryptic message.

I saw some traffic on the kernel mailing list that this problem was fixed in 2.6.11. Of course, this may or may not be the source of my problem. <sigh>