table of contents
| ACPI_IBM(4) | Device Drivers Manual | ACPI_IBM(4) | 
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_ibmAlternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):
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) and
    devd(8), through which applications can determine the
    status of various laptop components.
While the sysctl(8) interface is enabled automatically after loading the driver, the devd(8) 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.
devd(8) Events¶
Hotkey events received by devd(8) 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
led(4) Interface¶
The acpi_ibm driver provides a
    led(4) 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_ibmdriver 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_ibmdriver 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).
      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:
- 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:
- 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). Some
      ThinkPads have the below sensor layout which might vary depending on the
      specific model:
    
    - CPU
- Mini PCI Module
- HDD
- GPU
- Built-in battery
- UltraBay battery
- Built-in battery
- UltraBay battery
 
- dev.acpi_ibm.0.handlerevents
- devd(8) events handled by
      acpi_ibmwhen 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).
FILES¶
- /dev/led/thinklight
- ThinkLight led(4) device node
EXAMPLES¶
The following can be added to devd.conf(5) 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):
dev.acpi_ibm.0.handlerevents=0x04\ 0x10\ 0x11
SEE ALSO¶
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>.
| June 24, 2020 | Debian |