[SOLVED] How to change the Notebook LCD backlight brightness

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glup
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Joined: Fri Apr 17, 2020 3:40 pm

[SOLVED] How to change the Notebook LCD backlight brightness

Post by glup »

I hope I post my question at the right place.

My Panasonic Toughbook CF-31 Mk 3 shall be migrated to LM from Windows.
The current problem is that I can't change under Linux Mint the Backlight brightness. The key combination <Fn>+<F1> to reduce and <Fn>+<F2> to increase the brightness display a nice icon on the display while I press them but do not what the icon tells... It seams to be fixed at the medium brightness. During night much to bright and in the sun much to low.

Code: Select all

~$ inxi -Fxxxrz
System:
  Host: UGA Kernel: 5.3.0-51-generic x86_64 bits: 64 compiler: gcc v: 7.5.0 
  Desktop: Cinnamon 4.4.8 wm: muffin 4.4.2 dm: LightDM 1.26.0 
  Distro: Linux Mint 19.3 Tricia base: Ubuntu 18.04 bionic 
Machine:
  Type: Laptop System: Panasonic product: CF-31SBL741M v: 003 
  serial: <filter> Chassis: type: 10 v: 001 serial: <filter> 
  Mobo: Panasonic model: CF31-3 v: 1 serial: <filter> 
  BIOS: American Megatrends v: 3.00L14 date: 07/03/2014 
Battery:
  ID-1: BAT1 charge: 51.6 Wh condition: 80.7/91.0 Wh (89%) volts: 11.1/10.7 
  model: Panasonic CF-VZSU46 type: Li-ion serial: <filter> 
  status: Discharging 
CPU:
  Topology: Dual Core model: Intel Core i5-3320M bits: 64 type: MT MCP 
  arch: Ivy Bridge rev: 9 L2 cache: 3072 KiB 
  flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 20753 
  Speed: 1197 MHz min/max: 1200/3300 MHz Core speeds (MHz): 1: 1197 2: 1197 
  3: 1197 4: 1197 
Graphics:
  Device-1: Intel 3rd Gen Core processor Graphics vendor: Matsushita 
  driver: i915 v: kernel bus ID: 00:02.0 chip ID: 8086:0166 
  Display: x11 server: X.Org 1.20.5 driver: modesetting unloaded: fbdev,vesa 
  resolution: 1024x768~60Hz 
  OpenGL: renderer: Mesa DRI Intel Ivybridge Mobile v: 4.2 Mesa 19.2.8 
  compat-v: 3.0 direct render: Yes 
Audio:
  Device-1: Intel 7 Series/C216 Family High Definition Audio 
  vendor: Matsushita driver: snd_hda_intel v: kernel bus ID: 00:1b.0 
  chip ID: 8086:1e20 
  Sound Server: ALSA v: k5.3.0-51-generic 
Network:
  Device-1: Intel 82579LM Gigabit Network vendor: Matsushita driver: e1000e 
  v: 3.2.6-k port: f080 bus ID: 00:19.0 chip ID: 8086:1502 
  IF: enp0s25 state: down mac: <filter> 
  Device-2: Intel Centrino Advanced-N 6235 driver: iwlwifi v: kernel 
  port: f040 bus ID: 09:00.0 chip ID: 8086:088e 
  IF: wlp9s0 state: up mac: <filter> 
  IF-ID-1: wwan0 state: down mac: <filter> 
Drives:
  Local Storage: total: 465.76 GiB used: 13.00 GiB (2.8%) 
  ID-1: /dev/sda vendor: Samsung model: SSD 860 EVO 500GB size: 465.76 GiB 
  speed: 3.0 Gb/s serial: <filter> rev: 4B6Q scheme: MBR 
Partition:
  ID-1: / size: 447.03 GiB used: 12.76 GiB (2.9%) fs: btrfs dev: /dev/sda6 
  ID-2: /boot size: 453.0 MiB used: 242.7 MiB (53.6%) fs: ext4 
  dev: /dev/sda1 
  ID-3: /home size: 447.03 GiB used: 12.76 GiB (2.9%) fs: btrfs 
  dev: /dev/sda6 
  ID-4: swap-1 size: 3.81 GiB used: 0 KiB (0.0%) fs: swap dev: /dev/sda5 
Sensors:
  System Temperatures: cpu: 58.0 C mobo: N/A 
  Fan Speeds (RPM): N/A 
Repos:
  No active apt repos in: /etc/apt/sources.list 
  Active apt repos in: /etc/apt/sources.list.d/eh5-pulseaudio-a2dp-bionic.list 
  1: deb http://ppa.launchpad.net/eh5/pulseaudio-a2dp/ubuntu bionic main
  Active apt repos in: /etc/apt/sources.list.d/official-package-repositories.list 
  1: deb http://mirror.netcologne.de/linuxmint/packages tricia main upstream import backport
  2: deb http://ftp-stud.hs-esslingen.de/ubuntu bionic main restricted universe multiverse
  3: deb http://ftp-stud.hs-esslingen.de/ubuntu bionic-updates main restricted universe multiverse
  4: deb http://ftp-stud.hs-esslingen.de/ubuntu bionic-backports main restricted universe multiverse
  5: deb http://security.ubuntu.com/ubuntu/ bionic-security main restricted universe multiverse
  6: deb http://archive.canonical.com/ubuntu/ bionic partner
  Active apt repos in: /etc/apt/sources.list.d/tvheadend.list 
  1: deb https://apt.tvheadend.org/stable bionic main
Info:
  Processes: 257 Uptime: 2h 18m Memory: 7.64 GiB used: 2.51 GiB (32.8%) 
  Init: systemd v: 237 runlevel: 5 Compilers: gcc: 7.5.0 alt: 7 Shell: bash 
  v: 4.4.20 running in: gnome-terminal inxi: 3.0.32  
Last edited by glup on Mon Jun 08, 2020 8:50 pm, edited 1 time in total.
glup
Level 1
Level 1
Posts: 12
Joined: Fri Apr 17, 2020 3:40 pm

Re: How to change the Notebook LCD backlight brightness

Post by glup »

I found myself a solution:
  1. The redirect-brightness script from https://askubuntu.com/questions/1045624 ... tness-prob
  2. Change in the script

    Code: Select all

    WatchDriver="/sys/class/backlight/panasonic"
    PatchDriver="/sys/class/backlight/intel_backlight"
  3. Test it:

    Code: Select all

    sudo redirect-brightness -l
    and press Fn + F1 resp Fn + F2 multiple times, end Test with Ctrl + c
  4. Create a systemd service unit /etc/systemd/system/redirect-brightness.service to start it after boot

    Code: Select all

    [Unit]
    Description=Redirect Backlight Brightness from one driver to another
    
    [Service]
    ExecStart=/usr/local/bin/redirect-brightness
    
    [Install]
    WantedBy=basic.target
    
    Install, enable and start the service:

    Code: Select all

    sudo chmod 664 /etc/systemd/system/redirect-brightness.service
    sudo systemctl daemon-reload
    sudo systemctl enable redirect-brightness.service
    sudo systemctl start redirect-brightness.service
    
atzekatze
Level 1
Level 1
Posts: 1
Joined: Sun Apr 11, 2021 11:41 am

Re: [SOLVED] How to change the Notebook LCD backlight brightness

Post by atzekatze »

OMG, thank you so much, been struggling with this for so long now!
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