Re: uvcvideo causes ehci_hcd to halt

[Alan Stern]

On Thu, 22 Oct 2009, Laurent Pinchart wrote:

> On Wednesday 21 October 2009 22:09:46 Ozan Ã?aÄ?layan wrote:
> > Laurent Pinchart wrote:
> > > Probably because hal opens the device to query its capabilities and
> > > closes it right after. The driver submits the interrupt URB when the
> > > first user opens the device and cancels it when the last user closes the
> > > device.
> > 
> > So who's guilty now?
> > 
> > :)
> 
> Not me :-)
> 
> I don't think there's anything wrong with submitting an interrupt URB and 
> canceling it soon after.

Nothing wrong at all.  Even if hal didn't do this, the same thing might
very well occur the second time somebody ran a program accessing the
video device.

The real problem will be to figure out why the hardware isn't turning
off the periodic schedule.  It might be a timing issue (the schedule
was running too briefly before the driver tried to disable it).  That
could explain why it shows up only occasionally.  But if it isn't, I
have no idea what the underlying cause is or how to fix it.

Alan Stern

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