systemd-backlight (8) - Linux Manuals

systemd-backlight: Load and save the display backlight brightness at boot and shutdown

Command to display systemd-backlight manual in Linux: $ man 8 systemd-backlight

NAME

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

SYNOPSIS

systemd-backlight [at] .service

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

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

DESCRIPTION

systemd-backlight [at] .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.