SYSTEMD-BACKLIGHT@.SERVICE(8)

  .SH "NAME" systemd-backlight@.service, systemd-backlight - Load and save the display backlight brightness at boot and shutdown
  .SH "SYNOPSIS"
    .PP systemd-backlight@.service
    .PP /usr/lib/systemd/systemd-backlight

  .SH "DESCRIPTION"

    .PP systemd-backlight@.service is a service that restores the display backlight brightness at early boot and saves it at shutdown. On disk, the backlight brightness is stored in /var/lib/systemd/backlight/. During loading, if the udev property ID_BACKLIGHT_CLAMP is not set to false, the brightness is clamped to a value of at least 1 or 5% of maximum brightness, whichever is greater. This restriction will be removed when the kernel allows user space to reliably set a brightness value which does not turn off the display.

  .SH "KERNEL COMMAND LINE"

    .PP systemd-backlight understands the following kernel command line parameter:

      .PP systemd.restore_state=

            Takes a boolean argument. Defaults to 1. If 0, does not restore the backlight settings on boot. However, settings will still be stored on shutdown.
          .RE

      .SH "SEE ALSO"

        .PP systemd(1)