[pvrusb2] Poor analog picture on HVR-1950 after upgrade to 2.6.28 kernel

[Mike Isely]

On Fri, 12 Jun 2009, Mike Isely wrote:

> 
> FYI, here's the point when this problem was "fixed" last time:
> 
> http://www.isely.net/pvrusb2/history.html#pvrusb2-mci-20061119
> 
> That was over 2.5 years ago :-(
> 
> Still trying to characterize the extent of the problem this time...

More info:

The symptoms really do match what I had to deal with back in 2006.  I'm 
certain it's essentially the same problem.  But it gets more interesting 
than that.

Back then the problem involved proper initialization performed by the 
cx25840 driver.  The change I had made to the pvrusb2 driver at that 
time was to kick that driver in such a way that it did the right thing.  
Unfortunately the "right thing" is deep in the bowels of cx25840.ko and 
once I had gotten it to behave at that time I stopped pursuing it.

Back then the device experiencing the problem was the PVR-USB2 24xxx 
series - it was the first model handled by this driver to use the 
cx25840.  The 24xxx device and the HVR-1950 both use this chip. Well I 
just tested the older 24xxx device again - and it's still OK.  Whatever 
is going on here is actually specific to the HVR-1950.  That is the 
mystery.

Odds are pretty good that the pvrusb2 driver is correct and that the 
problem is in the cx25840 driver.  So I will have to pour through the 
that driver in v4l-dvb and see if I can figure out why it is treating 
the two devices differently.  I'll see how much headway I can make 
tonight.

Scott, Vincent - have either of you tried changing the horizontal 
capture resolution to 720 yet?

  -Mike

-- 

Mike Isely
isely @ isely (dot) net
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