[wplug] Re: IBM Thinkpad APM/ACPI: what to do next?

[Brandon Kuczenski]

On Thu, 2 Sep 2004, Tobin Fricke wrote:

> On Thu, 2 Sep 2004, Brandon Kuczenski wrote:
>
> > But, now in the bootup, APMD gives these messages:
> > Sep  2 16:58:35 localhost kernel: apm: BIOS version 1.2 Flags 0x03 (Driver
> > version 1.16ac)
> > Sep  2 16:58:35 localhost kernel: apm: overridden by ACPI.
>
> I had a similar problem on my Dell Inspiron.  IIRC, it turns out that ACPI
> and APM are incompatible.  I think you have to disable (remove) ACPI
> support in order for APM to work.  Or something to that effect.  You can
> accomplish this by giving "acpi=off" as a kernel parameter, via Lilo (or
> grub), or by removing it from the kernel.  The former is quick to try.

Another thought occurred to me while reading about ACPI and APM... since
ACPI supersedes APM in functionality, and since ACPI is already working on
my system, I might as well just use ACPI, right?

The fact that ACPI and APM were two tools for the same task was the
missing piece of information -- thanks.

I've since learned that ACPI only supports suspend-to-RAM, and that swsusp
is the suspend-to-disk tool to which you were referring, which is nice
when I need to leave my laptop off and unplugged for long periods of time.
In fact, leaving it suspended-to-RAM for basically 24-hours-a-day,
7-days-a-week might account for the premature failure of my hard drive
last month, I suppose (well, that plus IBM's notoriety in hard drives from
around 2001/2002...)

SWSUSP sounds like a fun project for the future, but it looks like it
requires a kernel rebuild.  Next time I need to do that I'll look into it.

-Brandon