Re: API to turn off the display

Greetings,

On Wed, 28 Jan 2004 13:19:02 -0500
John Baldwin <jhb_at_FreeBSD.org> wrote:
> On Wednesday 28 January 2004 01:11 pm, Scott Lambert wrote:
> > On Wed, Jan 28, 2004 at 08:32:15AM -0700, M. Warner Losh wrote:
> > > In message: <20040128045816.Y1089_at_alpha.siliconlandmark.com>
> > >
> > >             Andre Guibert de Bruet <andy_at_siliconlandmark.com> writes:
> > > : Through functionality provided by the BIOS. A 30-second
> > > : search through the source would have shown the answer in
> > > : /usr/src/sys/i386/bios/apm.c:334 with apm_display().
> > >
> > > My experience is that turning the display off via apm doesn't work on
> > > many laptops :-(.
> >
> > Is there anything that does; other than closing the lid?
> 
> Yes, there should be.  ACPI has an entire set of methods devoted to manging 
> displays including turning the displays on and off.  We just don't support 
> those yet.

I wrote a driver that handles what John told.

http://access.cent.saitama-u.ac.jp/~taku/freebsd/acpi_vid-20031013.tar.gz
MD5 (acpi_vid-20031013.tar.gz) = adbfa6931e505544fb784e00c7b974e7

This driver uses ACPI video extension to control display switching and
backlight brightness. So working ACPI is a requisition for this driver.

Whether it does or does not work depends heavily on how well the BIOS written,
however, I hope it worth trying.

Suggestions, working/not-working reports etc are very appreciated.

Sincerely,
taku
-- 
-|-__    YAMAMOTO, Taku  <taku_at_cent.saitama-u.ac.jp>
 | __ <

Post Scriptum: 
Due to recent instability of our campus network, downloading may fail.
Please try several times before giving it up if things didn't go well.
Sorry for inconvinience.