Bug#782442: USB3 external HDD not recognized [regression]

[Mathias Nyman <mathias.nyman@linux.intel.com>]

Hi

On 29.05.2015 15:35, Ralf Jung wrote:
> Hi again,
> 
>> Indeed doing "echo 'on' | sudo tee /sys/bus/pci/devices/*/power/control"
>> fixes the problem: When I subsequently plug in the disk, it is
>> recognized correctly. I confirmed this with an older kernel (the 3.16
>> Debian kernel, to be more precise). That's good to know, now I don't
>> need to reboot to a different kernel anymore to do fast backups ;-)
> 
> Is there any news on this? Any further information I can provide to help
> fix the issue?
> 

I got some untested and not yet reviewed usb3 resume race fixes from Zhuang Jin Can
If you can try them out and see if they help it would be great.
They are sitting in a topic branch called "xhci_usb3_pm_fixes" in my tree:
(5 extra patches on top of current usb-linus)

git://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git xhci_usb3_pm_fixes

If not, then the we need to change xhci resume code so that we resume the roothubs as default
except if we are runtime suspended and woken up just to be (system) suspended.

-Mathias