Am Mittwoch 25 November 2009 23:38:25 schrieb Alan Stern:
> On Wed, 25 Nov 2009, Stephan Diestelhorst wrote:
> You should add a dump_stack() line to handshake_on_error_set_halt(), 
> just after the ehci_err() call.  Then we'd be able to see the failure 
> pathway and determine whether it really was caused by the delay being 
> too short.

Will do that now and report back.

> > It might well be the case that the delay is too small. I will change
> > to a higher value (this and the device ID should eventually be
> > converted into symbolic constants).
>
> Otherwise a stress test is the only option.

I have bumped the delay up to 1000 us, and could not trigger the
issue, even with doing modprobe uvcvideo; rmmod uvcvideo in a loop for
several hundred interations, with varying delays between the insert
and removal. However, I am not sure, whether this is actually stress
testing anything.

> > Does anybody have a clue how to
> > properly determine the neccessary delay, either with a stress test or
> > by someone (Intel) telling us the hardware delay?
> 
> There hasn't been any feedback from Intel.  If you can find the right 
> person to ask, go ahead.

Nope. 

Cheers,
  Stephan
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