[gentoo-user] External USB HDD: device descriptor read/64, error -62 (solved?)

[Paul Hartman <paul.hartman+gentoo@gmail.com>]

I thought I would post this here for the archives and google in case
someone else has the same problem.

Tonight I rebooted for the first time in 60 days. In that time I've
changed from gentoo-sources-2.6.29-r1 to 2.6.29-r5 and countless
updates to my ~amd64 world.

I have an external LaCie 2TB USB hard drive which has been in use
those whole 60 days without problems. Much to my dismay, after
rebooting and plugging it in I got this in my dmesg:

[  144.963008] usb 2-7: new full speed USB device using ohci_hcd and
address 9
[  145.127007] usb 2-7: device descriptor read/64, error -62
[  145.796006] usb 2-7: device not accepting address 9, error -62
[  145.953007] usb 2-7: new full speed USB device using ohci_hcd and
address 10
[  146.117007] usb 2-7: device descriptor read/64, error -62
[  146.382007] usb 2-7: device descriptor read/64, error -62
[  146.640007] usb 2-7: new full speed USB device using ohci_hcd and
address 11
[  147.044914] usb 2-7: device not accepting address 11, error -62
[  147.201007] usb 2-7: new full speed USB device using ohci_hcd and
address 12
[  147.605006] usb 2-7: device not accepting address 12, error -62
[  147.605010] hub 2-0:1.0: unable to enumerate USB device on port 7

I tried unplugging and replugging both the USB and power cables
several times but still had the same error. After a bit of Googling I
saw one old post on another distro's site that suggested it might be a
power issue -- not with the power to the drive, but power to the USB
hub on the motherboard. In fact, I had at the time plugged in these
USB devices: keyboard, mouse, joystick, hard drive, monitor (which has
a two-port hub), webcam, and scanner. I also charge my cell phone via
USB, though it was not connected at the time. All 4 USB ports on the
back of the motherboard were in use, which is where the HDD was
plugged in, as well as 2 more of the "external" (case) ports which
also come from the motherboard. So I unplugged everything except for
the keyboard and mouse, then plugged the HDD back in to the same USB
port and magic! It works! fsck found no errors, my data is safe... and
I am /yet/ /again/ reminded to make backups of everything.

I cannot be sure that my USB power was being over-utilized, but I have
unplugged and re-plugged it a few times and it has kept working so
far. Perhaps I have a bad port or cable that only sometimes works and
happened to work by coincidence after I unplugged the other devices.

I thought I'd post it here in case anyone else like me has a mild
heart-attack thinking their drive has died. There is hope! :)