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SYSTEMD-B...@.SERVICE(8)  systemd-backlight@.service  SYSTEMD-B...@.SERVICE(8)

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

SYNOPSIS
       systemd-backlight@.service

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

       /usr/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. The percentage can be
       adjusted by specifying a percentage (needs to be suffixed with "%",
       e.g.  "30%") to the property ID_BACKLIGHT_CLAMP.

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.

           Added in version 209.

SEE ALSO
       systemd(1)

systemd 255                                           SYSTEMD-B...@.SERVICE(8)

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