broken nouveau dependency on power supply

[Benjamin Herrenschmidt]

On Mon, 2012-04-02 at 05:00 -0400, David Airlie wrote:
> >  - Better: Just make the bloody thing a bool :-) The power supply
> > framework itself is small enough, just make it a boolean option and
> > avoid the problem entirely. The actual power supply sub drivers can
> > remain modular of course.
> 
> We can just do select POWER_SUPPLY.

Well, select'ing otherwise user configurable options was still frowned
on last we discussed that... and it makes the whole inline stubs in
power_supply.h totally pointless :-)

> Yes it reduces the option range for some stupid corner case but really
> I don't care, removing features from the kernel that a driver depends
> on is just leading to insane state combination and QA problems.

Well, the power supply stuff only works if you have a backend for it,
which not all platforms are, and it's fairly safe to assume AC whenever
it's not actually supported.

(Talking of which, we should be able to do a PowerBook backend
reasonably easily).

I don't care which solution you guys end up choosing though, just fix
it :-)

Cheers,
Ben.