[linux-dvb] Re: CX88 i2c issue w/ DVB tuners

[Andrew de Quincey <adq_dvb@lidskialf.net>]

On Sunday 12 Sep 2004 15:35, Kenneth Aafløy wrote:
> On Sunday 12 September 2004 16:23, Andrew de Quincey wrote:
> > > > Not registering to the i2c core and calling the i2c read/write
> > > > functions directly solves this. You just need to check that the card
> > > > mutex is hold by the read/write functions.
> > >
> > > So you're suggesting using the i2c_adapter structure, but not
> > > registering it with the kernel? Gah, I wish I'd understood thats what
> > > you meant two days ago!
> >
> > Will this not cause problems with devices like the cx88 though - cards
> > using it can have other non-DVB i2c drivers which are registered with the
> > kernel i2c. I doubt they will work particularly well if they were given
> > an "unofficial" i2c_adapter.
> >
> > In that case, it would have to be registered, in which case autoprobing
> > is still a problem, hence why I am trying to fix autoprobing.
>
> I still don't see why this can't be solved in the dvb-drivers. The adapter
> itself can reject i2c-devices known to conflict with frontends in it's
> client_register function, or reject i2c-devices known not to exists on a
> particular adapter, hmm?
>
> This is the problem, right, or am I still far out? :)

Hmm yeah, but then the adapters have to know more than they should about other 
i2c devices in the system. And for things like the cx88 which can have dvb, 
video, tuner devices etc etc, you'd probably end up with complex ifs.  Also, 
as more i2c devices are implemented, more will clash in future, which will 
break things for a bit.

I just prefer a generic way of just saying "don't probe - I'll choose myself". 
Then the problem goes away.