Copyright (c) 2004 Mark Santcroos <marks@ripe.net>
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$FreeBSD: releng/10.2/share/man/man4/acpi_video.4 148066 2005-07-15 17:35:26Z hrs $
.Dd November 8, 2004 .Dt ACPI_VIDEO 4 .Os .Sh NAME .Nm acpi_video .Nd ACPI Video Extensions driver .Sh SYNOPSIS .Cd "device acpi_video" .Sh DESCRIPTION This driver uses the ACPI Video Extensions to control display switching and backlight brightness. The availability of the .Xr sysctl 8 variables depends on the functions offered by the host's ACPI implementation. .Sh SYSCTL VARIABLES The following sysctls are currently implemented, where .Aq Ar device is .Va crt , lcd , or .Va tv : l -tag -width indent t Va hw.acpi.video. Ns Ao Ar device Ac Ns Va .active Current state of the output device. t Va hw.acpi.video. Ns Ao Ar device Ac Ns Va .levels List of supported brightness levels. t Va hw.acpi.video. Ns Ao Ar device Ac Ns Va .brightness Current brightness level of the device. t Va hw.acpi.video. Ns Ao Ar device Ac Ns Va .fullpower Preset brightness level to be used in full power mode. t Va hw.acpi.video. Ns Ao Ar device Ac Ns Va .economy Preset brightness level to be used in economy mode. .El
p Defaults for these variables can be set in .Xr sysctl.conf 5 , which is parsed at boot-time. .Sh SEE ALSO .Xr acpi 4 , .Xr loader.conf 5 , .Xr sysctl.conf 5 , .Xr sysctl 8 .Sh HISTORY The .Nm driver first appeared in .Fx 5.3 . .Sh AUTHORS .An -nosplit The .Nm driver was written by .An Taku YAMAMOTO Aq taku@cent.saitama-u.ac.jp . This manual page was written by .An Mark Santcroos Aq marks@ripe.net . .Sh BUGS 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, .Xr acpi_toshiba 4 ) must be used instead.