acpi_video(4) ACPI Video Extensions driver


device acpi_video


This driver uses the ACPI Video Extensions to control display switching and backlight brightness. The availability of the sysctl(8) variables depends on the functions offered by the host's ACPI implementation.


The following sysctls are currently implemented, where Aq Ar device is crt , lcd or tv Ao device Ac .active
Current state of the output device. Ao device Ac .levels
List of supported brightness levels. Ao device Ac .brightness
Current brightness level of the device. Ao device Ac .fullpower
Preset brightness level to be used in full power mode. Ao device Ac .economy
Preset brightness level to be used in economy mode.

Defaults for these variables can be set in sysctl.conf5, which is parsed at boot-time.


The driver first appeared in Fx 5.3 .


An -nosplit The driver was written by An Taku YAMAMOTO Aq [email protected] . This manual page was written by An Mark Santcroos Aq [email protected] .


Some systems only perform output switching via SMM even though they export the proper information via ACPI. On such systems, the proper hotkeys or OEM driver (for example, acpi_toshiba4) must be used instead.