---
name: "acpi_ibm"
section: "4freebsd"
platform: "linux"
package: "freebsd-manpages"
version: "12.2-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/acpi_ibm/4freebsd"
---

# acpi\_ibm(4freebsd)

ACPI extras driver for IBM laptops

## NAME

**acpi\_ibm** – ACPI extras driver for IBM laptops

## SYNOPSIS

To compile this driver into the kernel, place the following line in your kernel configuration file:

**device acpi\_ibm**

Alternatively, to load the driver as a module at boot time, place the following line in [loader.conf(5)](/loader.conf/5.md):

```
acpi_ibm_load="YES"
```

## DESCRIPTION

The **acpi\_ibm** driver provides support for hotkeys and other components of IBM laptops. The main purpose of this driver is to provide an interface, accessible via [sysctl(8)](/sysctl/8.md) and [devd(8)](/devd/8.md), through which applications can determine the status of various laptop components.

While the [sysctl(8)](/sysctl/8.md) interface is enabled automatically after loading the driver, the [devd(8)](/devd/8.md) interface has to be enabled explicitly, as it may alter the default action of certain keys. This is done by setting the *events* sysctl as described below. Specifying which keys should generate events is done by setting a bitmask, whereas each bit represents one key or key combination. This bitmask, accessible via the *eventmask* sysctl, is set to *availmask* by default, a value representing all possible keypress events on the specific ThinkPad model.

### Xr devd 8 Events

Hotkey events received by [devd(8)](/devd/8.md) provide the following information:

- system

  "ACPI"

- subsystem

  "IBM"

- type

  The source of the event in the ACPI namespace. The value depends on the model.

- notify

  Event code (see below).

Depending on the ThinkPad model, event codes may vary. On a ThinkPad T41p these are as follows:

- 0x01

  Fn + F1

- 0x02

  Fn + F2

- 0x03

  Fn + F3 (LCD backlight)

- 0x04

  Fn + F4 (Suspend to RAM)

- 0x05

  Fn + F5 (Bluetooth)

- 0x06

  Fn + F6

- 0x07

  Fn + F7 (Screen expand)

- 0x08

  Fn + F8

- 0x09

  Fn + F9

- 0x0a

  Fn + F10

- 0x0b

  Fn + F11

- 0x0c

  Fn + F12 (Suspend to disk)

- 0x0d

  Fn + Backspace

- 0x0e

  Fn + Insert

- 0x0f

  Fn + Delete

- 0x10

  Fn + Home (Brightness up)

- 0x11

  Fn + End (Brightness down)

- 0x12

  Fn + PageUp (ThinkLight)

- 0x13

  Fn + PageDown

- 0x14

  Fn + Space (Zoom)

- 0x15

  Volume Up

- 0x16

  Volume Down

- 0x17

  Mute

- 0x18

  Access IBM Button

### Xr led 4 Interface

The **acpi\_ibm** driver provides a [led(4)](/led/4.md) interface for the ThinkLight. The ThinkLight can be made to blink by writing ASCII strings to the */dev/led/thinklight* device.

## SYSCTL VARIABLES

The following sysctls are currently implemented:

- *dev.acpi\_ibm.0.initialmask*

  (read-only) Bitmask of ACPI events before the **acpi\_ibm** driver was loaded.

- *dev.acpi\_ibm.0.availmask*

  (read-only) Bitmask of all supported ACPI events.

- *dev.acpi\_ibm.0.events*

  Enable ACPI events and set the *eventmask* to *availmask*. Without the **acpi\_ibm** driver being loaded, only the Fn+F4 button generates an ACPI event.

- *dev.acpi\_ibm.0.eventmask*

  Sets the ACPI events which are reported to [devd(8)](/devd/8.md). Fn+F3, Fn+F4 and Fn+F12 always generate ACPI events, regardless which value *eventmask* has. Depending on the ThinkPad model, the meaning of different bits in the *eventmask* may vary. On a ThinkPad T41p this is a bitwise OR of the following:

  - 1

    Fn + F1

  - 2

    Fn + F2

  - 4

    Fn + F3 (LCD backlight)

  - 8

    Fn + F4 (Suspend to RAM)

  - 16

    Fn + F5 (Bluetooth)

  - 32

    Fn + F6

  - 64

    Fn + F7 (Screen expand)

  - 128

    Fn + F8

  - 256

    Fn + F9

  - 512

    Fn + F10

  - 1024

    Fn + F11

  - 2048

    Fn + F12 (Suspend to disk)

  - 4096

    Fn + Backspace

  - 8192

    Fn + Insert

  - 16384

    Fn + Delete

  - 32768

    Fn + Home (Brightness up)

  - 65536

    Fn + End (Brightness down)

  - 131072

    Fn + PageUp (ThinkLight)

  - 262144

    Fn + PageDown

  - 524288

    Fn + Space (Zoom)

  - 1048576

    Volume Up

  - 2097152

    Volume Down

  - 4194304

    Mute

  - 8388608

    Access IBM Button

- *dev.acpi\_ibm.0.hotkey*

  (read-only) Status of several buttons. Every time a button is pressed, the respecting bit is toggled. It is a bitwise OR of the following:

  - 1

    Home Button

  - 2

    Search Button

  - 4

    Mail Button

  - 8

    Access IBM Button

  - 16

    Zoom

  - 32

    Wireless LAN Button

  - 64

    Video Button

  - 128

    Hibernate Button

  - 256

    ThinkLight Button

  - 512

    Screen Expand

  - 1024

    Brightness Up/Down Button

  - 2048

    Volume Up/Down/Mute Button

- *dev.acpi\_ibm.0.lcd\_brightness*

  Current brightness level of the display.

- *dev.acpi\_ibm.0.volume*

  Speaker volume.

- *dev.acpi\_ibm.0.mute*

  Indicates, whether the speakers are muted or not.

- *dev.acpi\_ibm.0.thinklight*

  Indicates, whether the ThinkLight keyboard light is activated or not.

- *dev.acpi\_ibm.0.bluetooth*

  Toggle Bluetooth chip activity.

- *dev.acpi\_ibm.0.wlan*

  (read-only) Indicates whether the WLAN chip is active or not.

- *dev.acpi\_ibm.0.fan*

  Indicates whether the fan is in automatic (1) or manual (0) mode. Default is automatic mode. This sysctl should be used with extreme precaution, since disabling automatic fan control might overheat the ThinkPad and lead to permanent damage if the *fan\_level* is not set accordingly.

- *dev.acpi\_ibm.0.fan\_level*

  Indicates at what speed the fan should run when being in manual mode. Valid values range from 0 (off) to 7 (max) and 8. Level 8 is used by the driver to set the fan in unthrottled mode. In this mode, the fan is set to spin freely and will quickly reach a very high speed. Use this mode only if absolutely necessary, e.g., if the system has reached its critical temperature and it is about to shut down. The resulting speed differs from model to model. On a T41p this is as follows:

  - 0

    off

  - 1, 2

    \~3000 RPM

  - 3, 4, 5

    \~3600 RPM

  - 6, 7

    \~4300 RPM

  - 8

    \~6400 RPM (Full-speed, unthrottled)

- *dev.acpi\_ibm.0.fan\_speed*

  (read-only) Fan speed in rounds per minute. A few older ThinkPads report the fan speed in levels ranging from 0 (off) to 7 (max).

- *dev.acpi\_ibm.0.thermal*

  (read-only) Shows the readings of up to eight different temperature sensors. Most ThinkPads include six or more temperature sensors but only expose the CPU temperature through [acpi\_thermal(4)](/acpi_thermal/4.md). Some ThinkPads have the below sensor layout which might vary depending on the specific model:

  1. CPU

  2. Mini PCI Module

  3. HDD

  4. GPU

  5. Built-in battery

  6. UltraBay battery

  7. Built-in battery

  8. UltraBay battery

- *dev.acpi\_ibm.0.handlerevents*

  [devd(8)](/devd/8.md) events handled by **acpi\_ibm** when *events* is set to 1. Events are specified as a whitespace-separated list of event code in hexadecimal or decimal form. Note that the event maybe handled twice (e.g., Brightness up/down) if ACPI BIOS already handled the event.

Defaults for these sysctls can be set in [sysctl.conf(5)](/sysctl.conf/5.md).

## FILES

- */dev/led/thinklight*

  ThinkLight [led(4)](/led/4.md) device node

## EXAMPLES

The following can be added to [devd.conf(5)](/devd.conf/5.md) in order to pass button events to a */usr/local/sbin/acpi\_oem\_exec.sh* script:

```
notify 10 {
        match "system"          "ACPI";
        match "subsystem"       "IBM";
        action "/usr/local/sbin/acpi_oem_exec.sh $notify ibm";
};
```

A possible */usr/local/sbin/acpi\_oem\_exec.sh* script might look like:

```
#!/bin/sh
#
if [ "$1" = "" -o "$2" = "" ]
then
        echo "usage: $0 notify oem_name"
        exit 1
fi
NOTIFY=`echo $1`
LOGGER="logger"
CALC="bc"
BC_PRECOMMANDS="scale=2"
ECHO="echo"
CUT="cut"
MAX_LCD_BRIGHTNESS=7
MAX_VOLUME=14
OEM=$2
DISPLAY_PIPE=/tmp/acpi_${OEM}_display
case ${NOTIFY} in
        0x05)
                LEVEL=`sysctl -n dev.acpi_${OEM}.0.bluetooth`
                if [ "$LEVEL" = "1" ]
                then
                        sysctl dev.acpi_${OEM}.0.bluetooth=0
                        MESSAGE="bluetooth disabled"
                else
                        sysctl dev.acpi_${OEM}.0.bluetooth=1
                        MESSAGE="bluetooth enabled"
                fi
                ;;
        0x10|0x11)
                LEVEL=`sysctl -n dev.acpi_${OEM}.0.lcd_brightness`
                PERCENT=`${ECHO} "${BC_PRECOMMANDS} ; \
                         ${LEVEL} / ${MAX_LCD_BRIGHTNESS} * 100" |\
                         ${CALC} | ${CUT} -d . -f 1`
                MESSAGE="brightness level ${PERCENT}%"
                ;;
        0x12)
                LEVEL=`sysctl -n dev.acpi_${OEM}.0.thinklight`
                if [ "$LEVEL" = "1" ]
                then
                        MESSAGE="thinklight enabled"
                else
                        MESSAGE="thinklight disabled"
                fi
                ;;
        0x15|0x16)
                LEVEL=`sysctl -n dev.acpi_${OEM}.0.volume`
                PERCENT=`${ECHO} "${BC_PRECOMMANDS} ; \
                        ${LEVEL} / ${MAX_VOLUME} * 100" | \
                         ${CALC} | ${CUT} -d . -f 1`
                MESSAGE="volume level ${PERCENT}%"
                ;;
        0x17)
                LEVEL=`sysctl -n dev.acpi_${OEM}.0.mute`
                if [ "$LEVEL" = "1" ]
                then
                        MESSAGE="volume muted"
                else
                        MESSAGE="volume unmuted"
                fi
                ;;
        *)
                ;;
esac
${LOGGER} ${MESSAGE}
if [ -p ${DISPLAY_PIPE} ]
then
        ${ECHO} ${MESSAGE} >> ${DISPLAY_PIPE} &
fi
exit 0
```

The following example specify that event code 0x04 (Suspend to RAM), 0x10 (Brightness up) and 0x11 (Brightness down) are handled by **acpi\_ibm**.

```
sysctl dev.acpi_ibm.0.handlerevents='0x04 0x10 0x11'
```

in [sysctl.conf(5)](/sysctl.conf/5.md):

```
dev.acpi_ibm.0.handlerevents=0x04\ 0x10\ 0x11
```

## SEE ALSO

[acpi(4)](/acpi/4.md), [led(4)](/led/4.md), [sysctl.conf(5)](/sysctl.conf/5.md), [devd(8)](/devd/8.md), [sysctl(8)](/sysctl/8.md)

## HISTORY

The **acpi\_ibm** device driver first appeared in FreeBSD 6.0.

## AUTHORS

The **acpi\_ibm** driver was written by Takanori Watanabe ⟨*takawata@FreeBSD.org*⟩ and later mostly rewritten by Markus Brueffer ⟨*markus@FreeBSD.org*⟩. This manual page was written by Christian Brueffer ⟨*brueffer@FreeBSD.org*⟩ and Markus Brueffer ⟨*markus@FreeBSD.org*⟩.
