[ltp] Re: [PATCH 2/2] Thinkpad Suspend Powersave: Add D2 power saving code for Thinkpads with Radeon video chipsets

[Theodore Ts'o]

On Thu, Mar 17, 2005 at 10:19:04AM +1100, Benjamin Herrenschmidt wrote:
> You probably want to remove the bit that does
> 
> 	OUTREG(TV_DAC_CNTL, INREG(TV_DAC_CNTL) | 0x07000000);
> 
> Or you'll lose TV output :)

I'm not using TV output, and the original patch stated:

> > +		/* Power down TV DAC, that saves a significant amount of power,
> > +		 * we'll have something better once we actually have some TVOut
> > +		 * support
> > +		 */

I suppose I should renable the TV DAC and see how much power it
actually consumes if I enable it.  It would seem to me that we should
have a way that we can power down whatever parts of the video chipset
that we're not using.  (For example if I don't have anything connected
to the VGA output, it would be good if we could power that down too...)

						- Ted