Re: Overly conservative xHCI bandwidth estimation

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On Fri, Nov 06, 2015 at 08:52:52AM +0800, Lu, Baolu wrote:
>> I reproduced the U1/U2 disconnect issues several times. I didn't try the
>> issue of not enough bandwidth for two devices.
> Can you please try the not enough bandwidth issue?

It doesn't work. I can use one card (it takes 3-4 tries to get it started due
to LPM bugs, but it works), but not two.

Note that I can use one card even if the other is plugged in. I just can't
use both at the same time.

> Can you cat /sys/bus/usb/devices/2-2/power/usb3_hardware_lpm_u1
> and /sys/bus/usb/devices/2-2/power/usb3_hardware_lpm_u2 for several
> times? Don't use that device when cat these two files.

I waited a bit longer, and indeed, now it consistently shows enabled on both
cards.

  klump:~> cat /sys/bus/usb/devices/2-1/power/usb3_hardware_lpm_u1
  enabled
  klump:~> cat /sys/bus/usb/devices/2-1/power/usb3_hardware_lpm_u2
  enabled
  klump:~> cat /sys/bus/usb/devices/2-2/power/usb3_hardware_lpm_u1
  enabled
  klump:~> cat /sys/bus/usb/devices/2-2/power/usb3_hardware_lpm_u2
  enabled

For fun, I tried also with a USB 2.0 cable. U1 and U2 comes up as disabled,
but of course, the device doesn't work.

/* Steinar */
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