[arch-general] Unable to mount external USB HD from two of my USB ports

[Robbie Smith]

On 20/10/12 00:16, Rodrigo Rivas wrote:
> On Fri, Oct 19, 2012 at 8:16 AM, Robbie Smith <zoqaeski at gmail.com> wrote:
>
>> I've been having troubles mounting an external USB HDD to two of the three
>> USB ports on my laptop. dmesg reports a timeout connecting to the device;
>> plugging in other devices to the same ports works fine with no errors. I've
>> attached the log here[1].
>>
>> The drive in question is a Seagate 1.5 TB Expansion Portable Drive, model
>> ST1500LM003-9YH148. I reformatted it upon purchase to have two partitions,
>> a NTFS one for Windows compatibility, and an Ext4 one for Linux backups and
>> miscellanea. Each partition is ~750GB in size.
>>
>> Any idea what is going on? I think the issue may be with the drive, which
>> is virtually brand new (I bought it ~3 months ago).
>>
>> [1] https://gist.github.com/3916478
>>
>
> Look at the working Verbatim drive:
>
> #Left:
>
> [ 1689.742443] usb 3-1: new high-speed USB device number 2 using xhci_hcd
> #Right:
>
> [ 2115.686272] usb 5-1: new high-speed USB device number 4 using ehci_hcd
>
> See any difference? Yes, one is Xhci and the other Ehci. AFAIK the
> xhci is USB3 and the ehci is USB2. So it seems that your HD is trying
> to use USB3 but it is failing. The other port, however, uses ehci
> directly and works fine.
>
> I guess that blacklisting the xhci-hcd driver should may it fallback
> to ehci and just work, but I don't have any USB3 device or
> motherboard, so I cannot tell for sure.
>
> Other option is to disable the USB3 support in the BIOS, if you can
> find such an option.
>
> HTH
> --
> Rodrigo
>
Ah. It was working on all three ports a couple of weeks ago; I normally 
use the right port for my USB dongle as it's too big to fit in the left 
ports. I obviously don't have logs from then to see whether it was being 
mounted as USB3 or 2.

Looking at the output of lshw, it seems that the left ports are xhci and 
the right one is ehci. There's also a lot of other USB "ports" listed, 
but I'm guessing those are used internally (keyboard uses USB driver 
perhaps?).

I'll try blacklisting the xhci-hcd driver and see what happens.