PERFORCE change 52156 for review

[Nate Lawson]

On Mon, 10 May 2004, John Baldwin wrote:
> On Saturday 08 May 2004 12:15 am, Nate Lawson wrote:
> > On Mon, 3 May 2004, John Baldwin wrote:
> > > http://perforce.freebsd.org/chv.cgi?CH=52156
> > >
> > > Change 52156 by jhb at jhb_slimer on 2004/05/03 12:10:39
> > >
> > > 	Bah, revert accidental submits.  Neither of these worked on my
> > > 	laptop, though the acpi_video one does work for some people and
> > > 	might should be committed.
> > >
> > > Affected files ...
> > >
> > > .. //depot/projects/power/sys/dev/acpica/acpi_video.c#4 edit
> > > .. //depot/projects/power/sys/isa/vga_isa.c#5 edit
> >
> > The DPMS stuff should go in a different device driver than acpi_video.  It
> > is a MI driver that implements only the standard ACPI interfaces.  DPMS is
> > probed separately and should be in a separate driver.  You can have DPMS
> > without ACPI too.
>
> I know.  My laptop doesn't have a device that acpi_video attaches to and it
> needs DPMS.  You can see I tried adding it to vga_isa.c and that didn't work
> either.  I have a start on a vgapci(4) driver that would attach to PCI
> devices that have the right class and subclass.  It would then have drm0,
> agp0 (for Intel onboard graphics), and I guess a dpms0 or vesa0 child device.
> That's trickier.  Partly because the only info I can find on DPMS, is to use
> the BIOS to do it via vm86, which is very i386-only.  Maybe there will be a
> dpms0 child and the default on x86 can be to attach the VESA version, but
> chip-specific drivers with a probe of 0 can be written for use on all archs
> if the DPMS frobbing really is chip specific.

I think DPMS should be a separate driver, not under the video driver.
There is DPMS on Sparc, for example, although I don't know how it is
implemented.

-Nate