Categories
Hardware Linux Ubuntu

Unable to enumerate USB device on port…

I have an old PC with what appears to be a broken implementation of USB. I cannot obtain a BIOS update and there is no BIOS setting to switch off USB either. Very old Linux distributions would run on this PC, but only on those with USB support as loadable modules. For later kernels with direct USB support I would get continuous error messages to the console.

After spending some time Googling, I found this useful post

For Ubuntu 10.04 LTS I used the advice to create rules to deactivate USB entirely on this host. The first file that I created was /etc/udev/rules.d/20-disable-ehci.rules which contained the following code:-

ACTION=="add", SUBSYSTEM=="pci", DRIVER=="ehci_hcd", \
        RUN+="/bin/sh -c 'echo -n %k > %S%p/driver/unbind'"

When I rebooted the PC, it disabled one of the troublesome USB hubs but I was still getting error messages for another but much more frequently now. I experimented by creating a similar file to deactivate ohci but this didn’t do anything. I tried again with uhci and that worked, USB completely disabled.
/etc/udev/rules.d/30-disable-uhci.rules

ACTION=="add", SUBSYSTEM=="pci", DRIVER=="uhci_hcd", \
        RUN+="/bin/sh -c 'echo -n %k > %S%p/driver/unbind'"

So if you have two or more USB hubs throwing enumeration errors, try disabling both EHCI and UHCI, it worked for me.

Obviously, if you have any USB devices that you need to use with this host, forget it. You will need a new motherboard.

Categories
Hardware Ubuntu

Find BIOS version using Ubuntu

I found this really simple way of finding the installed BIOS version on an Ubuntu PC without having to reboot. Simply execute the following command in a terminal session and scroll through the output until you find the BIOS section.

sudo dmidecode -s bios-version

For more system information, just scroll through the output until you find what you need.

sudo dmidecode | more

Update August 2012
I have successfully installed Lubuntu 10.04 on an old Toshiba Tecra 8000 (Pentium Mobile 233 with 256MB of RAM) and found that this trick to find the BIOS version did not work. The BIOS in my old Tecra is older than 1999 and doesn’t have the Desktop Management Interface present.