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11a1589223
Files which are installed as-is (any .service and other unit files, .conf files, .policy files, etc), are left as is. My assumption is that SPDX identifiers are not yet that well known, so it's better to retain the extended header to avoid any doubt. I also kept any copyright lines. We can probably remove them, but it'd nice to obtain explicit acks from all involved authors before doing that.
84 lines
2.7 KiB
XML
84 lines
2.7 KiB
XML
<?xml version="1.0"?>
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<!--*-nxml-*-->
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<!--
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SPDX-License-Identifier: LGPL-2.1+
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This file is part of systemd.
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Copyright 2013 Lennart Poettering
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-->
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<refentry id="systemd-backlight@.service" conditional='ENABLE_BACKLIGHT'>
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<refentryinfo>
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<title>systemd-backlight@.service</title>
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<productname>systemd</productname>
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<authorgroup>
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<author>
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<contrib>Developer</contrib>
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<firstname>Lennart</firstname>
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<surname>Poettering</surname>
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<email>lennart@poettering.net</email>
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</author>
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</authorgroup>
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</refentryinfo>
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<refmeta>
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<refentrytitle>systemd-backlight@.service</refentrytitle>
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<manvolnum>8</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>systemd-backlight@.service</refname>
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<refname>systemd-backlight</refname>
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<refpurpose>Load and save the display backlight brightness at boot and shutdown</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<para><filename>systemd-backlight@.service</filename></para>
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<para><filename>/usr/lib/systemd/systemd-backlight</filename></para>
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</refsynopsisdiv>
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<refsect1>
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<title>Description</title>
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<para><filename>systemd-backlight@.service</filename> is a service
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that restores the display backlight brightness at early boot and
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saves it at shutdown. On disk, the backlight brightness is stored
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in <filename>/var/lib/systemd/backlight/</filename>. During
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loading, if the udev property <option>ID_BACKLIGHT_CLAMP</option> is
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not set to false, the brightness is clamped to a value of at
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least 1 or 5% of maximum brightness, whichever is greater. This
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restriction will be removed when the kernel allows user space to
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reliably set a brightness value which does not turn off the
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display.</para>
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</refsect1>
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<refsect1>
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<title>Kernel Command Line</title>
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<para><filename>systemd-backlight</filename> understands the
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following kernel command line parameter:</para>
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<variablelist class='kernel-commandline-options'>
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<varlistentry>
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<term><varname>systemd.restore_state=</varname></term>
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<listitem><para>Takes a boolean argument. Defaults to
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<literal>1</literal>. If <literal>0</literal>, does not
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restore the backlight settings on boot. However, settings will
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still be stored on shutdown. </para></listitem>
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</varlistentry>
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</variablelist>
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</refsect1>
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<refsect1>
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<title>See Also</title>
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<para>
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<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
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</para>
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</refsect1>
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</refentry>
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