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ACPI (Advanced Configuration and Power Management Interface) is a power management system. It is part of the BIOS.



The following kernel options need to be activated for ACPI:

Power management and ACPI options  --->
    [*] Power Management support
        [*] ACPI (Advanced Configuration and Power Interface) Support  --->
            [*] Optional drivers
Optional drivers
Option Module Recommend Description
Deprecated /proc/acpi files - No Creates deprecated files in the procfs filesystem, which are now replaced by files in the sysfs filesystem.
Deprecated power /proc/acpi directories - No Creates deprecated files in the procfs filesystem, which are now replaced by files in the sysfs filesystem.
EC read/write access through /sys/kernel/debug/ec ec-debugfs No Debug interface to the Embedded Controller.
Deprecated /proc/acpi/event support - No Creates deprecated files in the procfs filesystem, which are now replaced by the input layer or netlink events.
AC Adapter ac Laptops Creates files to tell, if your system is connected to AC.
Battery battery Laptops Creates files to tell, if your system is powered by a battery.
Button button - Handles events on the power, sleep, and lid buttons.
Video video - Supports basic operations for graphics adapters.
Fan fan - Supports ACPI fan devices, allowing user-mode applications to perform basic fan control (on, off, status).
Dock dock - Supports ACPI-controlled docking stations and removable drive bays, see the acpi dock article.
Processor processor - Installs ACPI as the idle handler for Linux and uses ACPI C2 and C3 processor states to save power.
Processor Aggregator processor-aggregator - ACPI 4.0 function to perform specific processor configuration and control.
Thermal Zone thermal Yes Supports ACPI thermal zones to protect your processor against overheating.
NUMA support - -
Debug Statements - No
PCI slot detection driver pci-slot No Helps to correlate PCI bus addresses with physical slots
Container and Module Devices container - Supports ACPI Container and Module devices to hotplug nodes, CPUs, and memory.
Smart Battery System sbs, sbshc - Supports another type of access to battery information, found on some laptops.
Hardware Error Device hed - Supports the Hardware Error Device, which is used to report some hardware errors.
Allow ACPI methods to be inserted/replaced at run time custom-method No
ACPI Platform Error Interface (APEI) - - APEI allows to report errors (for example from the chipset) to the operating system.


Desktop environments react on the common events generated by ACPI. If a desktop environment is not installed or to have the system react on special events the ACPI package can be installed. Install the sys-power/acpid package:

root #emerge --ask sys-power/acpid

USE flags

There are no use flags available for sys-power/acpid at this time.


For acpid to be able to shutdown a SELinux system, make sure the sec-policy/selinux-shutdown package is installed and the /sbin/shutdown executable is re-labelled.


The scripts found in /etc/acpi define how the system reacts on ACPI events. They can be edited as necessary to meet the user's needs.

Boot service

The acpid service can now be started. While using openrc run:

root #/etc/init.d/acpid start

To have the acpid service start at boot time add it to the default runlevel:

root #rc-update add acpid default

In case of systemd:

root #systemctl enable acpid.service
root #systemctl start acpid.service

Advanced configuration

The default ACPI setup may be satisfactory for some users, however a little extra configuration may be required to get the acpid daemon to treat some basic ACPI events properly (AC power plug in/out, multimedia keys, etc.).

Modifications can be make to /etc/acpi/ along with /etc/acpi/events/default if necessary. Why not create a complicated setup that makes use of the /etc/acpi/actions and /etc/acpi/events capabilities? Simply put scripts and event files in those locations for advanced usage.

A basic file will probably be enough for most users, however the following is an example of what could be done using

FILE /etc/acpi/
# $Header: /etc/acpi/                          Exp $
# $Author: (c) 2012-2014 -tclover <tokiclover@dotfiles.> Exp $
# $License: MIT (or 2-clause/new/simplified BSD)         Exp $
# $Version: 2014/12/24 21:09:26                          Exp $
log() { logger -p daemon "ACPI: $*"; }
uhd() { log "event unhandled: $*"; }
set $*
[ -d /dev/snd ] && alsa=true || alsa=false
[ -d /dev/oss ] && oss=true || oss=false
amixer="amixer -q set Master"
ossmix="ossmix -- vmix0-outvol"
case $group in
		case $value in
			*0) log "switching to power.bat power profile"
				hprofile power.bat;;
			*1) log "switching to power.adp power profile"
				hprofile power.adp;;
			*) uhd $*;;
		case $value in
			*0) log "switching to power.adp power profile"
				hprofile power.adp;;
			*1) log "switching to power.adp power profile"
				hprofile power.adp;;
			*) uhd $*;;
		case $action in
				case "$id" in
					close) hibernate-ram;;
					open) :;;
					*) uhd $*;;
			power) shutdown -H now;;
			sleep) hibernate-ram;;
				$alsa && $amixer toggle;;
				$alsa && $amixer 3dB+
				$oss && $ossmix +3;;
				$alsa && $amixer 3dB-
				$oss && $ossmix -3;;
			*) uhd $*;;
		case $action in
			play) :;;
			stop) :;;
			prev) :;;
			next) :;;
			*) uhd $*;;
		case $id in
			*plug) :;;
			*) uhd $*;;
		case $action in
			displayoff) :;;
			*) uhd $*;;
	*) uhd $*;;
unset alsa oss amixer ossmix group action device id
# vim:fenc=utf-8:ft=sh:ci:pi:sts=4:sw=4:ts=4:
Notice that the above script is compatible with ALSA and OSS, so no extra actions are needed when switching OSS from ALSA or the opposite. Do not hesitate to edit the script!
The above script also makes use of a power management profile using hprofile. Refer to the hprofile article for more information.


ACPI events and actions examples for Lenovo ThinkPad T410