Advanced Power Management:
Suspend, sleep, and power off

Guides

• http://linux.oreilly.com/news/lnxkernel_1100.html

1 June 2003 Update

The 2.4.x kernel can be patched with ACPI, and the latest -ac is likely to have a pretty good working patch (I've never tried it). However, the alternative is to just go straight to the 2.5 kernel, where ACPI is integrated and working. For details, see Sigillo, where I have the 2.5.69 kernel working great with battery detection. I don't yet have software suspend working and may just leave it for the moment.

Quiet mutterings of dubious value

Energy is a module that controls the screen and will turn it off. But to control the hard drive and fans, you need the laptop power module; this is from KDE help:

Laptop Modules Notes In order to use the laptop modules, you must have the kernel APM package installed in your kernel. Useful information on how to do this can be found in the Battery Powered Linux mini-HOWTO at http://metalab.unc.edu/LDP/HOWTO/mini/Battery-Powered.html. If you want the suspend and standby menu commands to work then you should install the Linux apmd package (version 2.4 or later). See the package itself at http://www.suse.com/en/products/suse_linux/i386/packages_personal/apmd.html (so you have it). It would be nice to be able to leave your computer asleep and wake it up from afar when you needed to do work! Here's from the HowTo listed above:

How to activate APM support in Linux: It's easy - just recompile the Linux kernel. Check the Kernel-HOWTO if you don't know how to do that. When the configuration script reaches the "character devices" section, the default setting for full apm bios support in kernel version 2.0.30 or higher is:

Advanced Power Management BIOS support: Yes
Ignore USER SUSPEND: No
Enable PM at boot time: Yes
Make CPU Idle calls when idle: Yes
Enable console blanking using APM: Yes
Power off on shutdown: Yes

Please read the configuration script's help texts. They explain in detail what each option does. If you want to use them from non-root accounts you must mark the apm command 'set uid root'. To do this log on as root and enter: %chown root /usr/bin/apm;chmod +s /usr/bin/apm.

Note that SuSE 7.3 (at least the pro edition) includes a package called apmd that regulates power conseration; see. http://sdb.suse.de/sdb/en/html/apmd.html for a detailed description. I installed it from an RPM package I found on a SuSE mirror and turned the feature on by editing /etc/rc.config, which also contained a parameter to turn on NumLock. You can further customize the actions of APMD here: /etc/rc.config.d/apmd.rc.config. Here's the details on APM from less /proc/config.gz

# CONFIG_ACPI is not set
CONFIG_APM=y
# CONFIG_APM_IGNORE_USER_SUSPEND is not set
CONFIG_APM_DO_ENABLE=y
# CONFIG_APM_CPU_IDLE is not set
CONFIG_APM_DISPLAY_BLANK=y
# CONFIG_APM_RTC_IS_GMT is not set
CONFIG_APM_ALLOW_INTS=y