[Howto] Power Management for your laptop using ACPI

Earthwings · Last edited by Earthwings on Fri Mar 18, 2005 7:23 am; edited 6 times in total

Battery lifetime is too short? Your laptop is getting too hot? Want to hibernate like in Windows? This howto might help you. It's was getting too big to put it here in the forums, but it's still just one click away.

Edit: It's now available at http://www.gentoo.org/doc/en/power-management-guide.xml

I'd appreciate some comments, additions, suggestions etc. Have fun

For your convenience, here's a short outline of what is expecting you:

Power Management for Laptops in Gentoo Linux

Introduction
Prerequisites
--> The BIOS part
--> ACPI support for the kernel
--> Creating a "battery" runlevel
CPU Power Management
LCD Power Management
Disk Power Management
Power Management for other devices
--> Wireless Power Management
--> USB Power Management
Sleep states: sleep, standby, suspend to RAM, hibernate, suspend to disk
Extending with Profiles
FAQ / Troubleshooting

bombcar · Posted: Thu Mar 11, 2004 11:49 pm Post subject:

One way to make Gentoo know what it is booting into is to make the default runlevel very empty, and then all it does is decide if AC power is available, then boot to "acpower", but if only battery, boot to "battery"

dvc5 · Posted: Thu Mar 11, 2004 11:51 pm Post subject:

This is great! I've been looking for something like this for a long time. Now I just need a laptop w/ frequency scaling.

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Earthwings · Posted: Fri Mar 12, 2004 12:00 am Post subject:

Jefklak · l33t Joined: 26 Oct 2003 Posts: 818 Location: Belgium

Very nice guide, congrats!

I'm only having trouble with ACPID - he doesn't receive any events!
I tried watching my events with

Earthwings · Posted: Sat Mar 20, 2004 5:18 pm Post subject:

I don't have a file /proc/acpi/button/state. Instead, there are directories like /proc/acpi/button/lid/LID/ with file "info" and "state" inside. What do you get in dmesg when inserting the button module? I get

Jefklak · l33t Joined: 26 Oct 2003 Posts: 818 Location: Belgium

Duh, I meant the /proc/acpi/event file instead of the button/state file... I don't know if the .sh file is called when a button is pressed or a lid is opened or closed, how can I check this? Also, acpid seems t owork (same dmesg as you) but the state thing does not work... Yes, the files you mentionned excist but some way the events aren't passed or don't work correctly... Any idea?

Thanks!

jarealist · Apprentice Joined: 07 Oct 2002 Posts: 224

Thanks for the howto. However, I'm having a problem getting the following module to load:

<M> ACPI Processor P-States driver

I get this from modprobe:

modprobe acpi
FATAL: Error inserting acpi (/lib/modules/2.6.4-gentoo-r1/kernel/arch/i386/kernel/cpu/cpufreq/acpi.ko): Device or resource busy

Any suggestions? All the other modules load OK. Here is my /etc/modules.autoload.d/kernel-2.6.

ac
battery
button
fan
processor
thermal
acpi
pcmcia_core
ds
yenta_socket
sonypi
fglrx
av5100
ipw2100

I have a Sony Viao PCG-V505DX and I'm using gentoo-dev-sources kernel ( 2.6.4-gentoo-r1.)

Will this work compiled in? Thanks.

Kenja · n00b Joined: 21 Mar 2004 Posts: 27

Just a thought. I have an unlocked Athlon XP Mobile. The current Biostar I intend on using has multiplier settings in the BIOS. I don't expect it to work for my board, but MSI has a board that has software multiplier management. Currently they only have software for windows, but would this setup work for the MSI board as well. In theory would the MSI board use the same commands as a board in a laptop and in effect make for a quiet desktop PC?

Earthwings · Posted: Sat Apr 03, 2004 10:03 am Post subject:

Sorry for the long delay.

Jefklak: What laptop do you have? I read a few other posts where the same happens.

jarealist: It's the same for me. I haven't yet figured out what the problem is, but if you did, please post here.

Kenja: Sorry, I don't have any experience with that.

I'm currently working on the next major update for the guide supporting laptop_mode and Power Management Profiles. It looks promising, but will take some time to finish. Stay tuned.

Edit: laptop-mode now included

Jefklak · l33t Joined: 26 Oct 2003 Posts: 818 Location: Belgium

Dell Inspiron 5150.
I reinstalled my whole box -- still no go...

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Earthwings · Posted: Sat Apr 03, 2004 12:22 pm Post subject:

Have a look here, seems to be a common problem for the Dell 5100 serie.
http://forums.gentoo.org/viewtopic.php?t=154996

Jefklak · l33t Joined: 26 Oct 2003 Posts: 818 Location: Belgium

Thanks for the link, it seems common indeed, that sucks

I already recompiled my DSDT and I was able to solve 1 WARNING (no error) but there are still 4 left (see http://forums.gentoo.org/viewtopic.php?t=122145&start=75 ...)

I already flashed my bios to A29, ill check if there's a newer version...
_________________
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Kernel 2.6.9-nitro4! << hurrah

Earthwings · Posted: Thu Apr 08, 2004 8:15 pm Post subject:

Just stumbled over this
http://bugme.osdl.org/show_bug.cgi?id=1752

angagon · Posted: Sun Apr 18, 2004 3:41 pm Post subject:

I am using a program called hprofile at [url]hprofile.sf.net[/url]. It allows changing files anywhere (like /etc) so you can set it up for different power configurations and using ACPI change confs on plugging the power in or out. Or other things.
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TinheadNed · Posted: Sun Apr 18, 2004 10:51 pm Post subject:

Just to be picky, your suspend/hibernate section is slightly wrong. There are two different sets of suspend code in the 2.6 kernel, hence the two different suspend options. There is the original Software Suspend (swsusp) that requires a resume= command line to your swap space, and the new PM code (which is the config option that requires a hardcoded partition).

If both are compiled in the kernel then

Kuartzer · Posted: Tue May 04, 2004 6:39 pm Post subject:

Earthwings · Posted: Tue May 04, 2004 7:15 pm Post subject:

Putting acpid in boot runlevel is not sufficient because it doesn't generate an event. However, the idea to decide which runlevel to start in the end of the boot runlevel sounds good. I'm not sure if the current battery runlevel satisfies everything a proper default runlevel has to provide (list of critical services etc).
The workaround I did right now is putting this code in /etc/conf.d/local.start:

Kuartzer · Posted: Tue May 04, 2004 7:33 pm Post subject:

I belive that the batery runlevel it´s a full copy of the default one plus the energie savings settings.

Earthwings · Posted: Sun May 16, 2004 6:02 pm Post subject:

IIRC the main problem is that /sbin/rc reads out the SOFTLEVEL value too early to update it. You are right that creating another runlevel would be a solution however.

Earthwings · Posted: Sun May 16, 2004 6:03 pm Post subject:

I made another major update right now. Beneath some minor fixes I added a FAQ chapter and updated the suspend/hibernate section. It now mentions swsusp2, which is the first implementation for hibernation that works for me. It looks really promising, has a nice interface and even supports bootsplash. You definitely want to try it :wink:

blmartin777 · Posted: Mon May 17, 2004 9:08 pm Post subject:

I didn't have the directory
/sys/devices/system/cpu/cpu0/cpufreq/
and it wouldn't let me create one not sure what to do.

thanks

blmartin777 · Posted: Tue May 18, 2004 8:22 pm Post subject:

I still haven't been able to resolve my problem
NO: /sys/devices/system/cpu/cpu0/cpufreq/ and I can't create one
Any ideas on what I should do.

Earthwings · Posted: Tue May 18, 2004 8:52 pm Post subject:

Can you give some more details? Some hardware specs. and the relevant parts of the kernel config. Also make sure there's no "dumb" mistake like forgetting to mount /boot before copying the kernel etc.

blmartin777 · Posted: Tue May 18, 2004 9:23 pm Post subject:

I have a gentoo system up and running. I was following your how-to and it got to the part where you said to