キーボードバックライトのソースを表示

[[Category:キーボード]]
[[en:Keyboard backlight]]
キーボードのバックライトの輝度レベルを制御するには、さまざまな方法があります。
== 全メーカー共通 ==

明るさのレベルを管理する方法はさまざまで、{{Pkg|brightnessctl}} や {{Pkg|light}} など、これを実現するためのヘルパーツールもさまざまです。

{{ic|sys}} 疑似ファイルシステムは、キーボードバックライトへのインタフェースを公開します。現在の輝度レベルは {{ic|/sys/class/leds/tpacpi::kbd_backlight/brightness}} を読むことで得られます。例えば、最大の輝度レベルを得るには、以下のようにします。

 $ cat /sys/class/leds/tpacpi::kbd_backlight/max_brightness

明るさを 1 に設定する

 # echo 1 > /sys/class/leds/tpacpi::kbd_backlight/brightness

{{ic|brightnessctl}} を使用する場合、{{ic|brightnessctl --list}} で使用可能な輝度調整のリストを取得し、次に kbd のバックライト情報を表示することができます。

 $ brightnessctl --device='tpacpi::kbd_backlight' info

絶対値と相対値(%)で現在値、絶対値での最大値が表示されます。別の値を設定する場合

 $ brightnessctl --device='tpacpi::kbd_backlight' set 1

=== xset ===

Some keyboard manufactores are not recognized by {{Pkg|brightnessctl}} or {{Pkg|light}}, but you can use {{Pkg|xorg-xset}} to control its lights if you are running Xorg.

The first parameter {{ic|led}} turns on the led, and {{ic|-led}} turns it off, the {{ic|NUMBER}} parameters accepts integers for 1 to 32 (each number corresponds to a led in you system, keyboards seem to generally be number 3), or 'on' and 'off' (on will turn ALL lights on, and off will turn ALL lights off).

To turn on the lights:

 $ xset led NUMBER

To turn off the lights:

 $ xset -led NUMBER

=== D-Bus ===
[[D-Bus]] インタフェース経由でコンピュータのキーボードのバックライトを制御することができます。D-Bus を使用する利点は、デバイスファイルへの変更が必要なく、全てのメーカーで使えることです。

以下に [[Python]] 3 での実装例を示します。{{ic|/usr/local/bin/}} にスクリプトを置き、実行可能にします。{{ic|/usr/local/bin/kb-light.py +}} や {{ic|/usr/local/bin/kb-light.py -}} を実行するキーボードショートカットを作成することでキーボードの輝度を変えることができます。

{{hc|/usr/local/bin/kb-light.py|<nowiki>
#!/usr/bin/env python3
# coding: utf-8

from sys import argv
import dbus


def kb_light_set(delta):
    bus = dbus.SystemBus()
    kbd_backlight_proxy = bus.get_object(org.freedesktop.UPower, /org/freedesktop/UPower/KbdBacklight)
    kbd_backlight = dbus.Interface(kbd_backlight_proxy, org.freedesktop.UPower.KbdBacklight)

    current = kbd_backlight.GetBrightness()
    maximum = kbd_backlight.GetMaxBrightness()
    new = max(0, current + delta)

    if new >= 0 and new <= maximum:
        current = new
        kbd_backlight.SetBrightness(current)

    # Return current backlight level percentage
    return 100 * current / maximum

if __name__ == __main__:
    if len(argv[1:]) == 1:
        if argv[1] == "--up" or argv[1] == "+":
            # ./kb-light.py (+|--up) to increment
            print(kb_light_set(1))
        elif argv[1] == "--down" or argv[1] == "-":
            # ./kb-light.py (-|--down) to decrement
            print(kb_light_set(-1))
        else:
            print("Unknown argument:", argv[1])
    else:
        print("Script takes exactly one argument.", len(argv[1:]), "arguments provided.")</nowiki>}}

Alternatively the following bash one-liner will set the backlight to the value specified in the ''argument'':

{{bc|<nowiki>
setKeyboardLight () {
    dbus-send --system --type=method_call  --dest="org.freedesktop.UPower" "/org/freedesktop/UPower/KbdBacklight" "org.freedesktop.UPower.KbdBacklight.SetBrightness" int32:$1 
}</nowiki>
}}

==== On GNOME ====

The following can be run from a terminal or mapped to keybindings 

 $ gdbus call --session --dest org.gnome.SettingsDaemon.Power --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Keyboard.StepUp
 $ gdbus call --session --dest org.gnome.SettingsDaemon.Power --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Keyboard.StepDown

==== On MATE ====

{{Style|Informal and unclear description. No relevance to MATE.}}

In case you use [[MATE]] environment you might get tired with repeated lighting keyboard backlight while logging in, unlocking screen or waking up dimmed display. Following setup prevent from automatic lighting up during any action. The only triggers remain plugging in the adapter and fresh boot. After that you can control keyboard backlight only via hotkeys (eg. ThinkPad Fn + spacebar).

To prevent automatic lighting up just edit file {{ic|/usr/share/dbus-1/system.d/org.freedesktop.UPower.conf}} as follows (two occurrences of "deny"):

{{hc|/usr/share/dbus-1/system.d/org.freedesktop.UPower.conf|<nowiki>
<?xml version="1.0" encoding="UTF-8"?> <!-- -*- XML -*- -->

<!DOCTYPE busconfig PUBLIC
 "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
 "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<busconfig>
  <!-- Only root can own the service -->
  <policy user="root">
    <allow own="org.freedesktop.UPower"/>
  </policy>
  <policy context="default">

    <allow send_destination="org.freedesktop.UPower"
           send_interface="org.freedesktop.DBus.Introspectable"/>

    <allow send_destination="org.freedesktop.UPower"
           send_interface="org.freedesktop.DBus.Peer"/>
    <allow send_destination="org.freedesktop.UPower"
           send_interface="org.freedesktop.DBus.Properties"/>
    <allow send_destination="org.freedesktop.UPower.Device"
           send_interface="org.freedesktop.DBus.Properties"/>
    <deny  send_destination="org.freedesktop.UPower.KbdBacklight"
           send_interface="org.freedesktop.DBus.Properties"/>
    <allow send_destination="org.freedesktop.UPower.Wakeups"
           send_interface="org.freedesktop.DBus.Properties"/>

    <allow send_destination="org.freedesktop.UPower"
           send_interface="org.freedesktop.UPower"/>
    <allow send_destination="org.freedesktop.UPower"
           send_interface="org.freedesktop.UPower.Device"/>
    <deny  send_destination="org.freedesktop.UPower"
           send_interface="org.freedesktop.UPower.KbdBacklight"/>
    <allow send_destination="org.freedesktop.UPower"
	   send_interface="org.freedesktop.UPower.Wakeups"/>
  </policy>
</busconfig>
</nowiki>}}