Epson Stylus Photo R300 not detected even with 3.0.0-16

Can you please run the following commands and post their output here:

sudo /usr/lib/cups/backend/usb
sudo modprobe usblp
ls -l /dev/usb/lp*
sudo usb_printerid /dev/usb/lp0
sudo usb_printerid /dev/usb/lp1
sudo rmmod usblp

Can you also try the CUPS packages (cups + cups-filters, a backport from Precise) from my PPA:

https://launchpad.net/~till-kamppeter/+archive/ppa

Does this alternative CUPS version detect your printer?

$ sudo /usr/lib/cups/backend/usb
DEBUG: list_devices
DEBUG: usb_find_busses=5
DEBUG: usb_find_devices=7
direct usb://EPSON/Stylus%20Photo%20R300?serial=L15P10501281054100&interface=1 "EPSON Stylus Photo R300" "EPSON Stylus Photo R300" "MFG:EPSON;CMD:ESCPL2,BDC,D4;MDL:Stylus Photo R300;CLS:PRINTER;DES:EPSON Stylus Photo R300;" ""
sudo modprobe usblp
(no output)
sudo usb_printerid /dev/usb/lp0
GET_DEVICE_ID string:
MFG:EPSON;CMD:ESCPL2,BDC,D4;MDL:Stylus Photo R300;CLS:PRINTER;DES:EPSON Stylus Photo R300;
sudo usb_printerid /dev/usb/lp1
Error: No such file or directory: can't open '/dev/usb/lp1'
sudo rmmod usblp
(no output)
As for the two CUPS packages, I'll do that some time today (once I've figured out how). I do see the instructions on your page.

Please do some more tests before updating to my PPA:

The CUPS usb backend (of the CUPS which comes with Oneiric) already detects your printer, so I cannot imaging that you observe a behavior of CUPS not detecting your printer. You should have gotten an automatically generated print queue (or the old print queue is still available, your initial report shows that you have a correct print queue setup) and you should be able to print.

Make sure your print queue is enabled:

cupsenable EPSON-Stylus-Photo-R300

and that you choose "EPSON-Stylus-Photo-R300" as the printer in the print dialogs of the applications.

Can you also post the output of

lpinfo -l -v

Stop the command with Ctrl+C if it does not exit by itself.

If this all does not work, follow the instructions under "CUPS error_log" and "Capturing print job data" on https://wiki.ubuntu.com/DebuggingPrintingProblems

> Make sure your print queue is enabled:
> cupsenable EPSON-Stylus-Photo-R300
That was it. Before giving that command, Properties in the Printers GUI (for EPSON-Stylus-Photo-R300) hand shown a "Printer State:" of "off or unplugged", just like when I had first upgraded to oneiric and before taking the "proposed" kernel. Once I gave the cupsenable command (which produced no output), and tried Properties again, it had changed to "Idle". Once I saw "Idle", I knew it would work, which it did. Given all this, I believe that in the state it was in before the cupsenable, Properties should have shown for "Printer State:", instead of "off or unplugged", something more like "print queue disabled" with an option to enable it (or lacking that, a hint about the "cupsenable" command). Obviously, "off or unplugged" was incorrect (I wonder if there's a bug for that). Anyway, thank you. I am really grateful to have my printer working once again.

Usually, when you turn off the printer the queue gets disabled and the state reason gets set to "off or unplugged" and when the printer is turned on again, the print queue gets re-enabled. This is done to avoid that CUPS tries to repeat the job regularly generating CPU load by starting to render the job again and again, which would quickly run down a laptop's battery when one is on the go and therefore disconnected from the printer. A laptop user can simply send jobs into the disabled queue and these jobs get rendered and printed as soon as he is back home.

Perhaps the re-enabling did not happen when you turned on the printer the last time. Can you try to turn off and turn on your printer several times to see whether the queue gets disabled when the printer is off and enabled when the printer is on?

If it does not work, or sometimes not work, try the CUPS package from my PPA to see whether it gets more reliable then. Its USB backend uses a newer generation of libusb (the USB access library) and has also some bugs fixed.

I turned off the printer, but even with it off, the Properties still show "idle". Sounds like there may be a problem in both directions. I close the dialog, go back to the "gear" -> Printers, select my printer, and then choose Properties from the context menu. Tried many times, but it keeps saying "Idle" even though the printer is definitely off.

I installed cups 1.5.2-4~ppa1 and cups-filters 1.0.1-1~ppa1 (plus 4 additional packages that came along with them). However, I still see Printer State: Idle, even with the printer off.

Perhaps pressing on the Off button of your printer brings it only into a Standby model, leaving it visible for the computer. Do the commands of comment #2 still show the printer's presence when it is turned off?

The enabling and disabling can always be tested by disconnecting and reconnecting the USB cable.

lpinfo -l -v lists my printer if and only if it is turned on. But the Printer State: in Properties continues to say "Idle" whether it is on or off. If I physically disconnect the USB cable, the Printer State: setting under Properties STILL says "Idle".

I have put a slightly modified package of system-config-printer onto my PPA:

https://launchpad.net/~till-kamppeter/+archive/ppa

Can you try that? It seems that CUPS detects your printer well but not the UDEV handler of system-config-printer.

I think that has fixed it (installed 3 packages). It now seems to be tracking the actual on/off state of the printer. Thank you.

Thank you very much, then I will make this patch available for Precise.

Fixed in system-config-printer 1.3.8+20120201-0ubuntu4 in Precise.