Fixing screen savers

[Adam Jackson]

On Thu, 2010-10-28 at 08:51 -0700, Keith Packard wrote:
> On Thu, 28 Oct 2010 09:03:00 -0400, Adam Jackson <ajax at nwnk.net> wrote:
> 
> > This sounds like it's ignoring per-output DPMS.
> 
> We don't have per-output DPMS in RandR yet.

Well, we sure should.

> > I kind of want to drop the DPMS extension entirely if we can.  It's
> > really quite awful to implement since it's per-display state not
> > per-screen.  I'm not sure how much existing code relies on it though.
> 
> I'd be up for that. Not having it at all would simplify the code
> tremendously. My main concern is whether the ability to control all
> three DPMS intervals is required by any standard or legislation. What I
> don't want to see is some additional external configuration for DPMS
> intervals.

EnergyStar only specifies that the product must be shipped with the
display set to enter sleep mode within 15 minutes.  It makes no mention
of finer granularity for displays.  Later VESA specs even deprecate the
four levels entirely, the DPM spec supersedes the DPMS spec and folds
the Standby and Suspend states into the Off state (like most drivers do
anyway).

I think the core protocol saver mechanism is entirely sufficient to
cover the DPM on/off semantics.

- ajax