PERFORCE change 52156 for review

[John Baldwin]

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.

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org