[linux-dvb] CX22702 i2c gate

[Steve Toth]

Hi,

The cx22702 demod has an i2c gate which is opened and closed on demand 
to allow traffic to pass through to the pll. By default it's open. With 
the Nova-T-PCI this is fine, because all access to the PLL naturally 
happens via the demod driver. The cx22702 driver is the obvious place to 
unlock and lock the gate... it's a function of the part.

However, the breaks the upcoming HVR1100 driver (and will also break the 
next two drivers to come after the HVR1100).

The HVR1100 driver is a Hybrid Analog (V4L) and DVB-T animal. The same 
PLL is used in both cases. Analog works normally on a clean boot, but as 
soon a DVB is used, the gate is locked and subsequent V4L analog I2C 
activity fails with -REMOTEIO errors. As you'd expect, DVB continue to 
work happily.

For the time being I've removed the gate locking mechanism from the 
cx22702 driver. However, other than removing the gate/lock permanently, 
or manually via a parameter, does anyone have any suggestions?

Anyone know how the other demods do this? (Or if they have this feature?)

Steve