[linux-dvb] Re: kernel I2C question

[Holger Waechtler <holger@qanu.de>]

Kenneth Aafløy wrote:
> I've only had a peek at the usb drivers, and basically got sick reading the 
> old drivers at least, have not had a look at the vp* driver yet. Actually 
> focusing on getting the bttv driver up to speed now, but the bus bttv-core 
> interface is coded somewhat strangly. It would be very cool if someone would 
> clean up the usb drivers some, at least split frontend/driver code..
Only the ttusb-budget drivers uses a 'real' i2c bus interface, the 
ttusb-dec ones send high-level tuning requests and not i2c messages to 
the device.

The same for the DST driver (even if here the requests are again packed 
into i2c messages -- since the onboard 8051 uC has talks using it's i2c 
interface from it's firmware that contains the frontend driver with the 
host. The DST pseudo-frontend driver is by no means portable to any 
other device, thus it makes no sense to share source with other drivers).

Basically it is to expect that even more modern devices will use this 
more generic approach in the future and hide the i2c bus to the host. On 
the dec2000 it's still accessible, on the DST not.

In both cases it makes not really sense to access it despite early 
debugging, in a release driver the relevant code has nothing to do.

Holger