focal (8) systemd-backlight@.service.8.gz

Provided by: systemd_245.4-4ubuntu3.24_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


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)