FreeBSD 7.0 manual page repository

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acpi_video - ACPI Video Extensions driver



      acpi_video - 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 〈device〉 is crt,
      lcd, or tv:〈device〉.active
              Current state of the output device.〈device〉.levels
              List of supported brightness levels.〈device〉.brightness
              Current brightness level of the device.〈device〉.fullpower
              Preset brightness level to be used in full power mode.〈device〉.economy
              Preset brightness level to be used in economy mode.
      Defaults for these variables can be set in sysctl.conf(5), which is
      parsed at boot-time.
      acpi(4), loader.conf(5), sysctl.conf(5), sysctl(8)


      The acpi_video driver first appeared in FreeBSD 5.3.


      The acpi_video driver was written by Taku YAMAMOTO
      〈〉.  This manual page was written by Mark
      Santcroos 〈〉.


      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_toshiba(4)) must be used


Based on BSD UNIX
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