Re: API to turn off the display

From: Melvyn Sopacua <freebsd-current_at_webteckies.org>
Date: Thu, 29 Jan 2004 13:03:12 +0100
On Wednesday 28 January 2004 22:07, Taku YAMAMOTO wrote:
> 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.

Thank you very much for your work!
I've tested this with lcd0 and toggeling sysctl's works correctly. It doesn't 
get envoked on lid closure though.

I've tried to debug this, but I only get a lot of noisy stuff and nothing I 
can relate to video or display objects.
Could you advise on the preferred debug.acpi settings and what to look for?

PS: On resume in X the display is all wrong (appr. 640 wide, and screen bottom 
is in the middle), but this is an X problem most likely, with the nvidia 
driver and the 1280x800 resolution.
-- 
Melvyn

=======================================================
FreeBSD sarevok.idg.nl 5.2-CURRENT FreeBSD 5.2-CURRENT #0: Wed Jan 28 18:01:18 
CET 2004     
root_at_sarevok.lan.webteckies.org:/usr/obj/usr/src/sys/SAREVOK_NOAPM_NODEBUG  
i386
=======================================================

Received on Thu Jan 29 2004 - 03:03:34 UTC

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