Absolutely Tech

[Solved] Unable to enumerate USB device (Disabling ehci_hcd)

Some hardware just don’t work with ehci_hcd on Karmic Koala. My memory stick from transcend refused to work no matter what I did. After plugging the device nothing happened, doing dmesg showed me the following error:

Apr 18 10:59:04 dpac-laptop kernel: [73668.388060] usb 1-2: new high speed USB device using ehci_hcd and address 5
Apr 18 10:59:04 dpac-laptop kernel: [73668.473034] hub 1-0:1.0: unable to enumerate USB device on port 2

After searching a lot, I came to a conclusion that my device doesn’t work with USB 2.0. So I disabled the ehci_hcd to make it work.

Since Karmic doesn’t use ehci_hcd as a module, modprobe -r ehci_hcd no longer works. The module is compiled into kernel. To disable it execute the following commands in terminal:
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