Hi Morten,

On Monday 13 August 2007 08:25, Morten Mortensen wrote:
> - I own a couple of these "fine" Logitech webcams. Something *is* changing
> in the UVC-driver, because the driver I had until yesterday - a couple of
> weeks old - could run the Ultra Vision and the Fusion for a period of half
> a minute and up to three, four or even five minuttes.
>
> The latest UVC-driver runs for one to three seconds, so something has been
> changed, which influences this by an order of magnitude. These scenarios
> are absolutely identical for my instances of the Ultra Vision and the
> Fusion.

Have you used the same kernel for both tests ? Could you please try to find 
out which SVN revision introduced the problem ?

> One wonders how Logitech circumvents the problem in their Windows drivers.

They don't. The Windows USB stack seems to be slower than the Linux one, and 
it just doesn't trigger the problem. It's a matter of timings, and Logitech 
never noticed the problem. From the limited amount of knowledge I have about 
this bug, it seems there is a hardware problem which has been worked-around 
by a firmware hack in recent webcams. Both the hardware and the firmware are 
provided by the IC vendor, so Logitech isn't the only one to blame.

> One wonders *when* manufacturers implement reflashability of their
> monitors, webcams, etc.

The two issues here are support and cost. They don't want to support firmware 
reflashing, as that would mean replacing dead webcams. And flash costs more 
than ROM.

> Please keep up the good work.

Thanks. I'll do my best :-)

Regards,

Laurent Pinchart
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