Fixing USB Problems on a Thinkpad T41

Updated: 9/11/2006

For the past year or so, I've been flummoxed by laptop's USB subsystem (I have a Thinkpad T41 running Fedora Core 4). My USB mouse and thumb drive worked fine, but I wasted countless hours trying to get a printer or external hard drive connected. Plugging in one of those devices produced a series of messages like these in /var/log/messages:

Sep 10 12:15:33 localhost kernel: usb 4-4: new high speed USB device using ehci_hcd and address 7
Sep 10 12:15:34 localhost kernel: hub 4-0:1.0: Cannot enable port 4. Maybe the USB cable is bad?
Sep 10 12:15:34 localhost kernel: usb 4-4: new high speed USB device using ehci_hcd and address 8
Sep 10 12:15:35 localhost kernel: hub 4-0:1.0: Cannot enable port 4. Maybe the USB cable is bad?
Sep 10 12:15:35 localhost kernel: usb 4-4: new high speed USB device using ehci_hcd and address 9
Sep 10 12:15:35 localhost kernel: usb 4-4: device not accepting address 9, error -71

But I'm not one to give up, so once more into the breach. And finally, a solution appeared:

/sbin/modprobe -r ehci_hcd

At this point, my shiny external hard drive could be connected successfully, and I could finally get a printer working as well. I added this command to my rc.local file so it gets executed at each reboot.

Of course, there is a downside: the linux kernel module I have to remove (ehci_hcd) is the one that enables high-speed USB transfers. While my mouse doesn't care, my hard drive is on the slow side, it seems. But that's OK — it's just used at the moment for storing backups.

Directions for installing the drive after getting it connected are here. They worked flawlessly. I found the CUPS web interface the best way to set up my printer.