Re: S3 wakeup code

Pavel Machek
2003-07-25T15:30:17Z

Hi!

> My problem is the backlight on a Dell Inspiron 8100 with the nVidia VGA
> controller. Everything seems to work as expected in all modes detected
> (S0, S1, S3, S4bios, S4, S5), except that the backlight stays on after
> "echo [1,3] > /proc/acpi/sleep". S1 just refrigerates everything, and
> leaves the display on, resume works fine.
>
> S3 refrigerates everything and suspends, leaving the display white.
> Resuming turns the backlight off. I can retrieve the backlight with the
> LCD/CRT button.
>
> Both S4's behave properly (full power off/restore with the power button).
>
> What part of the code should I look at to attack this problem (ACPI
> tables, linux/arch/i386/kernel/acpi/*, or linux/drivers/acpi/*)? DSDT
> compiles ok with the iasl assembler/disassembler, and Windows XP goes into
> standby properly; so I assume that the ACPI tables can be driven by the
> OS. Perhaps something along the lines of the asus_acpi code?

Video is hard to do... You should write specific suspend/resume
support for your video card. Bad luck if you are using vesafb :-(.

> > Wakeup code should *not* be machine-specific, but video card
> > save/restore is obviously video-card specific (and you basically can't
> > get docs). Write beeping code in 8086 assembly and start debuggin'
> > ;-))).

--
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]