Provided by: systemd_251.4-1ubuntu7_amd64 bug

NAME

       systemd-backlight@.service, systemd-backlight - Load and save the display backlight
       brightness at boot and shutdown

SYNOPSIS

       systemd-backlight@.service

       /lib/systemd/systemd-backlight save [backlight|leds]:DEVICE

       /lib/systemd/systemd-backlight load [backlight|leds]:DEVICE

DESCRIPTION

       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.

KERNEL COMMAND LINE

       systemd-backlight understands the following kernel command line parameter:

       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.

SEE ALSO

       systemd(1)