[TriLUG] Laptop ACPI S3 and swsusp2

[Ed Hill]

On Tue, 2005-07-05 at 16:42 -0400, David McDowell wrote:
> I just got an IBM T42 (not the p unfortunately so I have XGA instead
> of SXGA) on the EPP and it runs well.  I'm running CentOS 4.1 but have
> NO ACPI sleep/standy options available to me right now.  New thread?? 
> If anyone has any tips for me, that'd be great.  :)

Hi David,

To get ACPI S3 ("suspend to RAM") to work, please try adding:

  pci=noacpi acpi_sleep=s3_bios

to your kernel options.  With that in place and with the USB and WiFi
kernel modules unloaded, the S3 suspend mode works very nicely and
reliably for me:

  modprobe -r usb-controller1
  modprobe -r usb-controller
  killall dhclient
  modprobe -r eth1
  modprobe -r eth0
  echo -n 3 > /proc/acpi/sleep


Another option is swsusp2.  A guy in Germany is providing an excellent
set of FC3 and FC4 kernels and other RPMs that support swsusp2.  The
directions and downloads are at:

  http://mhensler.de/swsusp/

and the main project page is:

  http://www.suspend2.net/

One of the really nice things about swsusp2 is that it doesn't require
any special hardware support.  So it should theoretically work on any
laptop or desktop.  And it burns no battery power over time.

I've found that some recent SELinux "targeted" policies in FC3 and FC4
will disable swsusp2 so I've disabled SELinux.  As always, YMMV...  ;-)

Ed

-- 
Edward H. Hill III, PhD
office:  MIT Dept. of EAPS;  Rm 54-1424;  77 Massachusetts Ave.
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