Brightness control at f11 & f12 is not working

I know this is a common problem, but I still wants to find out a solution. Here is the output of inxi -Fxxxza :

System:
  Kernel: 5.10.15-120-tkg-bmq x86_64 bits: 64 compiler: gcc v: 10.2.1
  parameters: intel_pstate=passive BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq
  root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3
  quiet splash
  Desktop: KDE Plasma 5.21.0 tk: Qt 5.15.2 info: latte-dock wm: kwin_x11 dm: SDDM
  Distro: Garuda Linux
Machine:
  Type: Laptop System: LENOVO product: 81Y3 v: IdeaPad L3 15IML05 serial: <filter>
  Chassis: type: 10 v: IdeaPad L3 15IML05 serial: <filter>
  Mobo: LENOVO model: LNVNB161216 v: SDK0J40688 WIN serial: <filter> UEFI: LENOVO
  v: EJCN18WW date: 05/08/2020
Battery:
  ID-1: BAT0 charge: 20.5 Wh condition: 34.6/36.0 Wh (96%) volts: 11.6/11.2
  model: SMP L18M3PF2 type: Li-poly serial: <filter> status: Unknown cycles: 20
CPU:
  Info: Dual Core model: Intel Core i3-10110U bits: 64 type: MT MCP arch: Kaby Lake
  note: check family: 6 model-id: 8E (142) stepping: C (12) microcode: DE
  L2 cache: 4 MiB
  flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 20823
  Speed: 1976 MHz min/max: 400/2100 MHz Core speeds (MHz): 1: 1976 2: 2054 3: 2100
  4: 1923
  Vulnerabilities: Type: itlb_multihit status: KVM: VMX disabled
  Type: l1tf status: Not affected
  Type: mds status: Not affected
  Type: meltdown status: Not affected
  Type: spec_store_bypass
  mitigation: Speculative Store Bypass disabled via prctl and seccomp
  Type: spectre_v1
  mitigation: usercopy/swapgs barriers and __user pointer sanitization
  Type: spectre_v2 mitigation: Enhanced IBRS, IBPB: conditional, RSB filling
  Type: srbds mitigation: TSX disabled
  Type: tsx_async_abort status: Not affected
Graphics:
  Device-1: Intel UHD Graphics vendor: Lenovo driver: i915 v: kernel bus ID: 00:02.0
  chip ID: 8086:9b41 class ID: 0300
  Device-2: NVIDIA GP108M [GeForce MX330] vendor: Lenovo driver: nvidia v: 460.39
  alternate: nouveau,nvidia_drm bus ID: 01:00.0 chip ID: 10de:1d16 class ID: 0302
  Device-3: Syntek Integrated Camera type: USB driver: uvcvideo bus ID: 1-7:3
  chip ID: 174f:244e class ID: 0e02 serial: <filter>
  Display: x11 server: X.Org 1.20.10 compositor: kwin_x11 driver:
  loaded: modesetting,nvidia alternate: fbdev,intel,nouveau,nv,vesa display ID: :0
  screens: 1
  Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 508x285mm (20.0x11.2")
  s-diag: 582mm (22.9")
  Monitor-1: eDP-1 res: 1920x1080 hz: 60 dpi: 142 size: 344x194mm (13.5x7.6")
  diag: 395mm (15.5")
  OpenGL: renderer: Mesa Intel UHD Graphics (CML GT2) v: 4.6 Mesa 20.3.4
  direct render: Yes
Audio:
  Device-1: Intel Comet Lake PCH-LP cAVS vendor: Lenovo driver: snd_hda_intel
  v: kernel alternate: snd_soc_skl,snd_sof_pci bus ID: 00:1f.3 chip ID: 8086:02c8
  class ID: 0403
  Sound Server: ALSA v: k5.10.15-120-tkg-bmq
Network:
  Device-1: Intel Comet Lake PCH-LP CNVi WiFi driver: iwlwifi v: kernel port: 5000
  bus ID: 00:14.3 chip ID: 8086:02f0 class ID: 0280
  IF: wlp0s20f3 state: up mac: <filter>
  Device-2: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet vendor: Lenovo
  driver: r8169 v: kernel port: 3000 bus ID: 02:00.0 chip ID: 10ec:8168
  class ID: 0200
  IF: enp2s0 state: down mac: <filter>
Bluetooth:
  Device-1: Intel Bluetooth 9460/9560 Jefferson Peak (JfP) type: USB driver: btusb
  v: 0.8 bus ID: 1-10:4 chip ID: 8087:0aaa class ID: e001
  Message: Required tool hciconfig not installed. Check --recommends
Drives:
  Local Storage: total: 1.14 TiB used: 119.89 GiB (10.2%)
  SMART Message: Unable to run smartctl. Root privileges required.
  ID-1: /dev/nvme0n1 maj-min: 259:0 vendor: Lenovo model: UMIS RPJTJ256MEE1OWX
  size: 238.47 GiB block size: physical: 512 B logical: 512 B speed: 31.6 Gb/s
  lanes: 4 rotation: SSD serial: <filter> rev: 2.0C0628 temp: 36.9 C scheme: GPT
  ID-2: /dev/sda maj-min: 8:0 vendor: Western Digital model: WD10SPZX-08Z10
  size: 931.51 GiB block size: physical: 4096 B logical: 512 B speed: 6.0 Gb/s
  rotation: 5400 rpm serial: <filter> rev: 1A05 scheme: GPT
Partition:
  ID-1: / raw size: 100 GiB size: 100 GiB (100.00%) used: 19.25 GiB (19.2%)
  fs: btrfs dev: /dev/nvme0n1p5 maj-min: 259:5
  ID-2: /boot/efi raw size: 260 MiB size: 256 MiB (98.46%) used: 58.9 MiB (23.0%)
  fs: vfat dev: /dev/nvme0n1p1 maj-min: 259:1
  ID-3: /home raw size: 300 GiB size: 294.29 GiB (98.10%) used: 9.49 GiB (3.2%)
  fs: ext4 dev: /dev/sda4 maj-min: 8:4
  ID-4: /var/log raw size: 100 GiB size: 100 GiB (100.00%) used: 19.25 GiB (19.2%)
  fs: btrfs dev: /dev/nvme0n1p5 maj-min: 259:5
  ID-5: /var/tmp raw size: 100 GiB size: 100 GiB (100.00%) used: 19.25 GiB (19.2%)
  fs: btrfs dev: /dev/nvme0n1p5 maj-min: 259:5
Swap:
  Alert: No Swap data was found.
Sensors:
  System Temperatures: cpu: 56.0 C mobo: N/A
  Fan Speeds (RPM): N/A
Info:
  Processes: 241 Uptime: 1h 23m wakeups: 1 Memory: 7.52 GiB used: 4.15 GiB (55.2%)
  Init: systemd v: 247 Compilers: gcc: 10.2.0 clang: 11.1.0 Packages: pacman: 1564
  lib: 413 flatpak: 0 Shell: fish v: 3.1.2 running in: alacritty inxi: 3.3.01

This problem existed when I was still using Arch Linux with KDE, and I can't remember the time when I was using openSUSE or Linux Mint... It was a long time ago.

Start by reading usual knowledge.
After study, check

ls  /sys/class/backlight/
find  /sys/class/backlight/*/*brightness -type f -printf "%f "  -exec cat {} \;
systemctl status systemd-backlight@backlight*

Then rephrase your questions on the new basis. :wink:

3 Likes
lrwxrwxrwx 0 root 20 Feb 21:29 intel_backlight -> ../../devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight
actual_brightness 5334
brightness 5334
max_brightness 26666
● systemd-backlight@backlight:intel_backlight.service - Load/Save Screen Backlight Brightness of backlight:intel_backlight
     Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
     Active: active (exited) since Sat 2021-02-20 17:59:22 +08; 3h 32min ago
       Docs: man:systemd-backlight@.service(8)
    Process: 408 ExecStart=/usr/lib/systemd/systemd-backlight load backlight:intel_backlight (code=exited, status=0/SUCCESS)
   Main PID: 408 (code=exited, status=0/SUCCESS)

Feb 20 17:59:22 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:intel_backlight...
Feb 20 17:59:22 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:intel_backlight.```

What is your new question?

2 Likes

I cannot use my keyboard shortcut to adjust the brightness. My key mapping is fn+f11 for decreasing brightness and fn+f12 for increasing brightness.

So, study went useless...
Have you tried anything suggested in Archwiki article?
Should I start the step-by-step guide? (this guide does not exist)

Try kernel parameters, check, investigate.
After you have done some effort and failed, you may get some help.
Sorry, I also have my own backlight issues and still investigating. I am not a guru. I hope a guru could help me too...

If you are afraid of doing investigation, you have probably chosen the wrong distro.

3 Likes

Well... I did tried kernel parameters, backlight utilities, and many other method that I can't even remember. NONE of them works.

You are not helping with zero description. None works is not saying anything.

So, if I try suggesting the same it would make this a nightmare.
Be specific, keep notes, be responsible.
No magicians around here.

3 Likes

Be specificty, I tried ACPI method with kernel command -line and udev rules: not working, then I tried to use backlight utility, which I tried everyone of them. Not working. Then, I try to find solution on the web: I found nothing works for me.

You're exhausting my patience my friend.
WHAT? needs answer. several, few, all is not an answer.
Either start co-operating or I close this topic.

2 Likes

Sorry... I'm still a newbie. I would like to spend time on investigating, but I don't actually know how to investigate correctly... I'm just doing everything the archwiki told and see if it works. I think I need someone to give me some help about how to investigate my problem. I like to use Arch, but I really have a few experience on investigating. Please give me some advice.

That's what's needed.
Read man journalctl
Make a plan.
Write it down (paper and pencil required).
Execute and log the results (copy/paste terminal output).
Post execution steps and results log in forum post.

2 Likes

OK, I will try it out. It may take a few days to get a result... I will try my best to do it. Thank for the advice.

2 Likes
5 Likes

I found that when I use nomodeset kernel parameter, it broke my plymouth boot screen and I cannot boot, neither getting the journal. This is the output of journalctl -b | grep backlight where I use kernel parameter acpi_backlight=video :

Feb 21 13:20:19 Jinglebell kernel: Command line: BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3 quiet splash acpi_backlight=video
Feb 21 13:20:19 Jinglebell kernel: Kernel command line: intel_pstate=passive BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3 quiet splash acpi_backlight=video
Feb 21 13:20:20 Jinglebell systemd[1]: Created slice system-systemd\x2dbacklight.slice.
Feb 21 13:20:20 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:acpi_video0...
Feb 21 13:20:21 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:acpi_video0.
Feb 21 13:20:21 Jinglebell audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:acpi_video0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 21 13:20:21 Jinglebell kernel: audit: type=1130 audit(1613884821.004:13): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:acpi_video0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 21 13:20:21 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:intel_backlight...
Feb 21 13:20:21 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:intel_backlight.
Feb 21 13:20:21 Jinglebell audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:intel_backlight comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 21 13:20:21 Jinglebell kernel: audit: type=1130 audit(1613884821.032:14): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:intel_backlight comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 21 13:20:37 Jinglebell dbus-daemon[459]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.30' (uid=1000 pid=2951 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 13:20:37 Jinglebell dbus-daemon[459]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 13:27:35 Jinglebell dbus-daemon[459]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.30' (uid=1000 pid=2951 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 13:27:35 Jinglebell dbus-daemon[459]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 13:28:50 Jinglebell dbus-daemon[459]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.30' (uid=1000 pid=2951 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 13:28:50 Jinglebell dbus-daemon[459]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 13:29:17 Jinglebell dbus-daemon[459]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.30' (uid=1000 pid=2951 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 13:29:17 Jinglebell dbus-daemon[459]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'

And the brightness control is not working.

This is the output of journalctl -b | grep backlight where I use kernel parameter acpi_backlight=vendor :

Feb 21 13:43:21 Jinglebell kernel: Command line: BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3 quiet splash acpi_backlight=vendor
Feb 21 13:43:21 Jinglebell kernel: Kernel command line: intel_pstate=passive BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3 quiet splash acpi_backlight=vendor
Feb 21 13:43:22 Jinglebell systemd[1]: Created slice system-systemd\x2dbacklight.slice.
Feb 21 13:43:22 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:ideapad...
Feb 21 13:43:22 Jinglebell systemd-backlight[367]: ideapad: Failed to read current brightness: Invalid argument
Feb 21 13:43:22 Jinglebell systemd[1]: systemd-backlight@backlight:ideapad.service: Main process exited, code=exited, status=1/FAILURE
Feb 21 13:43:22 Jinglebell systemd[1]: systemd-backlight@backlight:ideapad.service: Failed with result 'exit-code'.
Feb 21 13:43:22 Jinglebell systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:ideapad.
Feb 21 13:43:22 Jinglebell audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:ideapad comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=failed'
Feb 21 13:43:23 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:intel_backlight...
Feb 21 13:43:23 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:intel_backlight.
Feb 21 13:43:23 Jinglebell audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:intel_backlight comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 21 13:43:41 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 13:43:41 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'

So far I didn't see any difference between this two journal. Am I doing it wrong? Somebody please tell me.

In this case you had only intel_backlight.

This seems a good start. If it was without any kernel parameters, then remove them from grub. (If you change grub kernel parameters, update grub and reboot).

Make sure what the proper key combination is, reading your laptop User Manual. Some BIOSes offer swapping Fn keys with Quick Access keys combinations.

On a clean boot,

  • check if one of Fn+F11, Fn+F12, F11, F12 change brightness (press each one twice)
  • Mark and share if and which ones produce visual feedback (screen window for brightness level change).

If you are still on the same situation, recheck current backlight logging and data and post

/bin/ls /sys/class/backlight/
systemctl status systemd-backlight@backlight*
journalctl -b | grep -E "brightness|backlight"
grep backlight /usr/lib/udev/rules.d/*.rules
grep backlight /etc/udev/rules.d/*.rules

Do not skip any of the above steps

2 Likes

I think I found something... When I use acpi_backlight=vendor, there is a ideapad directory in/sys/class/backlight. And I cannot change my screen brightness with key combination nor plasmoids (the plasmoids work before).
Here is the output of systemctl status systemd-backlight@backlight:ideapad.service:

systemd-backlight@backlight:ideapad.service - Load/Save Screen Backlight Brightness of backlight:ideapad
     Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
     Active: failed (Result: exit-code) since Sun 2021-02-21 13:43:22 +08; 17h ago
       Docs: man:systemd-backlight@.service(8)
   Main PID: 367 (code=exited, status=1/FAILURE)

Feb 21 13:43:22 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:ideapad...
Feb 21 13:43:22 Jinglebell systemd-backlight[367]: ideapad: Failed to read current brightness: Invalid argument
Feb 21 13:43:22 Jinglebell systemd[1]: systemd-backlight@backlight:ideapad.service: Main process exited, code=exited, status=1/FAILURE
Feb 21 13:43:22 Jinglebell systemd[1]: systemd-backlight@backlight:ideapad.service: Failed with result 'exit-code'.
Feb 21 13:43:22 Jinglebell systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:ideapad.

And this is the output of systemctl status systemd-backlight@backlight:intel_backlight.service:

● systemd-backlight@backlight:intel_backlight.service - Load/Save Screen Backlight Brightness of backlight:intel_backlight
     Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
     Active: active (exited) since Sun 2021-02-21 13:43:23 +08; 17h ago
       Docs: man:systemd-backlight@.service(8)
   Main PID: 394 (code=exited, status=0/SUCCESS)
      Tasks: 0 (limit: 9207)
     Memory: 0B
     CGroup: /system.slice/system-systemd\x2dbacklight.slice/systemd-backlight@backlight:intel_backlight.service

Feb 21 13:43:23 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:intel_backlight...
Feb 21 13:43:23 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:intel_backlight.

Here is the log:

Feb 21 13:43:21 Jinglebell kernel: Command line: BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3 quiet splash acpi_backlight=vendor
Feb 21 13:43:21 Jinglebell kernel: Kernel command line: intel_pstate=passive BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3 quiet splash acpi_backlight=vendor
Feb 21 13:43:22 Jinglebell systemd[1]: Created slice system-systemd\x2dbacklight.slice.
Feb 21 13:43:22 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:ideapad...
Feb 21 13:43:22 Jinglebell systemd-backlight[367]: ideapad: Failed to read current brightness: Invalid argument
Feb 21 13:43:22 Jinglebell systemd[1]: systemd-backlight@backlight:ideapad.service: Main process exited, code=exited, status=1/FAILURE
Feb 21 13:43:22 Jinglebell systemd[1]: systemd-backlight@backlight:ideapad.service: Failed with result 'exit-code'.
Feb 21 13:43:22 Jinglebell systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:ideapad.
Feb 21 13:43:22 Jinglebell audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:ideapad comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=failed'
Feb 21 13:43:23 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:intel_backlight...
Feb 21 13:43:23 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:intel_backlight.
Feb 21 13:43:23 Jinglebell audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:intel_backlight comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 21 13:43:41 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 13:43:41 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 14:10:08 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 14:10:08 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 14:17:45 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 14:17:45 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 14:31:06 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 14:31:06 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 14:32:21 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 14:32:21 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 14:33:36 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 14:33:36 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 15:50:29 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 15:50:29 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 15:59:13 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 15:59:13 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:08:40 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:08:40 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:09:55 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:09:55 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:11:10 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:11:10 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:17:04 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:17:04 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:24:27 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:24:27 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:34:18 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:34:18 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:36:48 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:36:48 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:38:03 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:38:03 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:39:18 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:39:18 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 16:54:31 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 16:54:32 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:00:54 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:00:54 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:02:09 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:02:09 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:03:24 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:03:24 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:05:47 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:05:47 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:11:58 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:11:59 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:16:01 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:16:01 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:17:16 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:17:16 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:18:31 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:18:31 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:38:47 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:38:47 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:55:13 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:55:13 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:56:28 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:56:28 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 17:57:43 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 17:57:43 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 18:51:20 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 18:51:20 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 19:02:54 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 19:02:54 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 19:04:09 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 19:04:09 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 21 19:05:24 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 21 19:05:24 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 22 06:45:01 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 22 06:45:01 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 22 06:58:12 Jinglebell dbus-daemon[457]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.26' (uid=1000 pid=2949 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 22 06:58:12 Jinglebell dbus-daemon[457]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
Feb 22 07:05:04 Jinglebell polkit-kde-authentication-agent-1[2944]: Message of action:  "Authentication is required to start 'systemd-backlight@backlight:ideapad.service'."
Feb 22 07:05:06 Jinglebell polkitd[463]: Operator of unix-session:2 successfully authenticated as unix-user:jing to gain TEMPORARY authorization for action org.freedesktop.systemd1.manage-units for system-bus-name::1.511 [systemctl start systemd-backlight@backlight:ideapad.service] (owned by unix-user:jing)
Feb 22 07:05:06 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:ideapad...
Feb 22 07:05:06 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:ideapad.
Feb 22 07:05:06 Jinglebell audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:ideapad comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 22 07:05:06 Jinglebell kernel: audit: type=1130 audit(1613948706.722:334): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:ideapad comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'

Here is the grep backlight /usr/lib/udev/rules.d/*.rules command output:

/usr/lib/udev/rules.d/71-seat.rules:# Assign keyboard and LCD backlights to the seat
/usr/lib/udev/rules.d/71-seat.rules:SUBSYSTEM=="backlight", TAG+="seat"
/usr/lib/udev/rules.d/99-systemd.rules:# Pull in backlight save/restore for all backlight devices and
/usr/lib/udev/rules.d/99-systemd.rules:# keyboard backlights
/usr/lib/udev/rules.d/99-systemd.rules:SUBSYSTEM=="backlight", TAG+="systemd", IMPORT{builtin}="path_id", ENV{SYSTEMD_WANTS}+="systemd-backlight@backlight:$name.service"
/usr/lib/udev/rules.d/99-systemd.rules:SUBSYSTEM=="leds", KERNEL=="*kbd_backlight", TAG+="systemd", IMPORT{builtin}="path_id", ENV{SYSTEMD_WANTS}+="systemd-backlight@leds:$name.service"

And this is grep backlight /etc/udev/rules.d/*.rules:

/etc/udev/rules.d/backlight.rules:ACTION=="add", SUBSYSTEM=="backlight", KERNEL=="intel_backlight", GROUP="video", MODE="0664"

I made this udev rule according to ArchWiki.

Here when I use acpi_backlight=native and acpi_backlight=none (their log are the same):
systemctl status systemd-backlight@backlight:intel_backlight.service

systemd-backlight@backlight:intel_backlight.service - Load/Save Screen Backlight Brightness of backlight:intel_backlight
     Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
     Active: active (exited) since Mon 2021-02-22 09:41:44 +08; 2min 30s ago
       Docs: man:systemd-backlight@.service(8)
   Main PID: 403 (code=exited, status=0/SUCCESS)
      Tasks: 0 (limit: 9207)
     Memory: 0B
     CGroup: /system.slice/system-systemd\x2dbacklight.slice/systemd-backlight@backlight:intel_backlight.service

Feb 22 09:41:44 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:intel_backlight...
Feb 22 09:41:44 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:intel_backlight.

journalctl -b | grep -E "brightness|backlight":

Feb 22 09:41:42 Jinglebell kernel: Command line: BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3 quiet splash acpi_backlight=native
Feb 22 09:41:42 Jinglebell kernel: Kernel command line: intel_pstate=passive BOOT_IMAGE=/@/boot/vmlinuz-linux-tkg-bmq root=UUID=8e775f0f-1ed0-43b7-8e05-8c1830cbceaa rw rootflags=subvol=@ loglevel=3 quiet splash acpi_backlight=native
Feb 22 09:41:44 Jinglebell systemd[1]: Created slice system-systemd\x2dbacklight.slice.
Feb 22 09:41:44 Jinglebell systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:intel_backlight...
Feb 22 09:41:44 Jinglebell systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:intel_backlight.
Feb 22 09:41:44 Jinglebell audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:intel_backlight comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 22 09:41:44 Jinglebell kernel: audit: type=1130 audit(1613958104.180:10): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-backlight@backlight:intel_backlight comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Feb 22 09:42:43 Jinglebell dbus-daemon[453]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.33' (uid=1000 pid=6079 comm="/usr/lib/org_kde_powerdevil ") (using servicehelper)
Feb 22 09:42:43 Jinglebell dbus-daemon[453]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'

Nothing change, the key still not working, and I can change my brightness through plasmoid.

I wanted to help you, not being a magician, a mind reader or a Linux expert.
I asked you to follow exact instructions and you still do what you think right.

I can't help this way.
I hope you find the solution and post it, so I can fix it on my Ideapad too.
Looking forward to your help! :slightly_smiling_face:

2 Likes

May I ask a question? Should I install the acpi package to make ACPI work?