More advanced power savings (rev. the DPMS extension).

[Egbert Eich]

Jim Gettys writes:
 > On Mon, 2006-07-31 at 15:41 -0400, Alex Deucher wrote:
 > 
 > > Would it make sense to use the chip's built in standy timer (somehow
 > > linked to the DPMS timer) or just explicitly enable or disable standby
 > > mode when we handle DPMS events?  Some chips may have more fine
 > > grained control over which parts of the chip get shutdown when they
 > > you may want to kick in before a DPMS event (like auto-shutdown of
 > > FIFOs or the overlay when you aren't using it).  I suppose they could
 > > be done as driver specific options.
 > > 
 > 
 > 
 > One of the features I asked for (and got) in DCON is the following:
 >   a register I can set to disable the LCD after a period of time.
 > 
 > Why did I ask for hardware for this?
 > 
 > Because in the meanwhile, long before the screen saver has kicked in and
 > blanked the screen, we'll have powered down the entire system (suspend
 > to RAM) while leaving the screen on with the DCON driving it, and having
 > to resume from RAM to just turn off the screen seemed worth the cost of
 > a register.  So I can have the processor off long before the screen goes
 > to a blank state, and not have to wake the processor to get the screen
 > saver to ultimately trigger.
 > 
 > Moral: I don't necessarily want user space to have to handle everything.

Right. It should be a driver feature. One that will hopefully be
configurable 'on the fly' once the infrastrucutre is there.

Cheers,
	Egbert.