Comment 12 for bug 35638

There's nothing out of the ordinary in dmesg...

[4294957.288000] usb 1-2: new full speed USB device using uhci_hcd and address 3
[4294957.415000] drivers/usb/class/usblp.c: usblp0: USB Bidirectional printer dev 3 if 0 alt 0 proto 2 vid 0x04F9 pid 0x0002

There are no other usb events in dmesg even though the printer appears and disappears from lpinfo -v . The printer continues to show up in lsusb.

Here is the lpinfo -v when the printer has "disappeared":

network socket
network beh
network bluetooth
network http
network ipp
network lpd
direct canon:/dev/usblp0
direct epson:/dev/usblp0
network smb

Notice how "direct canon" and "direct epson" are still there. These go when the printer usb cable is unplugged...