recently happened to me aswell and also doesn’t work on 5.16’s
was working well but looks like a recent upgrade broke something
if i check /sys/class/backlight/amdgpu_bl0/actual_brightness doesn’t change, but /sys/class/backlight/nvidia_0/actual_brightness does
the workaround is to change it like this (0-100)
echo 100 | sudo tee /sys/class/backlight/amdgpu_bl0/brightness
i’ll try first changing the kernel command on grub and if doesn’t work i’ll downgrade the kernel to find the latests that had it working
my setup
❯ inxi -Fxxxza --no-host
System:
Kernel: 5.16.7-200.fc35.x86_64 x86_64 bits: 64 compiler: gcc
v: 2.37-10.fc35 parameters: BOOT_IMAGE=/boot/vmlinuz-5.16.7-200.fc35.x86_64
root=UUID=1c1e5ff4-629c-46b0-bd2e-d57c77b40b6e ro rhgb quiet
rd.driver.blacklist=nouveau modprobe.blacklist=nouveau
nvidia-drm.modeset=1 amdgpu.backlight=0
Desktop: GNOME 41.3 tk: GTK 3.24.31 wm: gnome-shell dm: GDM 41.3
Distro: Fedora release 35 (Thirty Five)
Machine:
Type: Laptop System: LENOVO product: 82B1 v: Lenovo Legion 5 15ARH05H
serial: <superuser required> Chassis: type: 10 v: Lenovo Legion 5 15ARH05H
serial: <superuser required>
Mobo: LENOVO model: LNVNB161216 v: SDK0R33126 WIN
serial: <superuser required> UEFI: LENOVO v: FSCN14WW date: 08/26/2020
Battery:
ID-1: BAT0 charge: 48.1 Wh (58.9%) condition: 81.6/80.0 Wh (102.0%)
volts: 15.6 min: 15.4 model: SMP L19M4PC1 type: Li-poly serial: <filter>
status: N/A cycles: 14
CPU:
Info: model: AMD Ryzen 7 4800H with Radeon Graphics bits: 64 type: MT MCP
arch: Zen 2 family: 0x17 (23) model-id: 0x60 (96) stepping: 1
microcode: 0x8600104
Topology: cpus: 1x cores: 8 tpc: 2 threads: 16 smt: enabled cache:
L1: 512 KiB desc: d-8x32 KiB; i-8x32 KiB L2: 4 MiB desc: 8x512 KiB
L3: 8 MiB desc: 2x4 MiB
Speed (MHz): avg: 1444 high: 1958 min/max: 1400/2900 boost: disabled
scaling: driver: acpi-cpufreq governor: performance cores: 1: 1958 2: 1396
3: 1690 4: 1411 5: 1397 6: 1398 7: 1397 8: 1397 9: 1341 10: 1346 11: 1397
12: 1397 13: 1397 14: 1397 15: 1397 16: 1397 bogomips: 92624
Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3 svm
Vulnerabilities:
Type: itlb_multihit status: Not affected
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
Type: spectre_v1
mitigation: usercopy/swapgs barriers and __user pointer sanitization
Type: spectre_v2 mitigation: Full AMD retpoline, IBPB: conditional,
IBRS_FW, STIBP: conditional, RSB filling
Type: srbds status: Not affected
Type: tsx_async_abort status: Not affected
Graphics:
Device-1: NVIDIA TU106M [GeForce RTX 2060 Mobile] vendor: Lenovo
driver: nvidia v: 510.47.03 alternate: nouveau,nvidia_drm bus-ID: 01:00.0
chip-ID: 10de:1f15 class-ID: 0300
Device-2: AMD Renoir vendor: Lenovo driver: amdgpu v: kernel
bus-ID: 05:00.0 chip-ID: 1002:1636 class-ID: 0300
Device-3: Chicony Integrated Camera type: USB driver: uvcvideo
bus-ID: 3-3:2 chip-ID: 04f2:b6c2 class-ID: 0e02 serial: <filter>
Display: wayland server: X.Org 1.21.1.4 compositor: gnome-shell driver:
loaded: amdgpu note: n/a (using device driver) - try sudo/root
display-ID: :0 screens: 1
Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 508x286mm (20.0x11.3")
s-diag: 583mm (23")
Monitor-1: XWAYLAND0 res: 1920x1080 hz: 144 dpi: 143
size: 340x190mm (13.4x7.5") diag: 389mm (15.3")
OpenGL:
renderer: AMD RENOIR (DRM 3.44.0 5.16.7-200.fc35.x86_64 LLVM 13.0.0)
v: 4.6 Mesa 21.3.5 direct render: Yes
Audio:
Device-1: NVIDIA TU106 High Definition Audio driver: snd_hda_intel
v: kernel bus-ID: 01:00.1 chip-ID: 10de:10f9 class-ID: 0403
Device-2: AMD Raven/Raven2/FireFlight/Renoir Audio Processor
vendor: Lenovo driver: N/A
alternate: snd_pci_acp3x, snd_rn_pci_acp3x, snd_pci_acp5x, snd_pci_acp6x
bus-ID: 05:00.5 chip-ID: 1022:15e2 class-ID: 0480
Device-3: AMD Family 17h HD Audio vendor: Lenovo driver: snd_hda_intel
v: kernel bus-ID: 05:00.6 chip-ID: 1022:15e3 class-ID: 0403
Sound Server-1: ALSA v: k5.16.7-200.fc35.x86_64 running: yes
Sound Server-2: PulseAudio v: 15.0 running: no
Sound Server-3: PipeWire v: 0.3.45 running: yes
Network:
Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet
vendor: Lenovo driver: r8169 v: kernel port: 2000 bus-ID: 03:00.0
chip-ID: 10ec:8168 class-ID: 0200
IF: eno1 state: down mac: <filter>
Device-2: Intel Wi-Fi 6 AX200 driver: iwlwifi v: kernel bus-ID: 04:00.0
chip-ID: 8086:2723 class-ID: 0280
IF: wlp4s0 state: up mac: <filter>
Bluetooth:
Device-1: Intel AX200 Bluetooth type: USB driver: btusb v: 0.8
bus-ID: 5-3:3 chip-ID: 8087:0029 class-ID: e001
Report: rfkill ID: hci0 rfk-id: 2 state: up address: see --recommends
Drives:
Local Storage: total: 476.94 GiB used: 219.02 GiB (45.9%)
SMART Message: Unable to run smartctl. Root privileges required.
ID-1: /dev/nvme0n1 maj-min: 259:0 vendor: Samsung
model: MZALQ512HALU-000L2 size: 476.94 GiB block-size: physical: 512 B
logical: 512 B speed: 31.6 Gb/s lanes: 4 type: SSD serial: <filter>
rev: BL2QFXV7 temp: 33.9 C scheme: GPT
Partition:
ID-1: / raw-size: 27.94 GiB size: 27.33 GiB (97.83%)
used: 18.07 GiB (66.1%) fs: ext4 dev: /dev/nvme0n1p2 maj-min: 259:2
ID-2: /boot/efi raw-size: 512 MiB size: 511 MiB (99.80%)
used: 89.8 MiB (17.6%) fs: vfat dev: /dev/nvme0n1p1 maj-min: 259:1
ID-3: /home raw-size: 310.63 GiB size: 304.75 GiB (98.11%)
used: 200.87 GiB (65.9%) fs: ext4 dev: /dev/nvme0n1p5 maj-min: 259:5
Swap:
Kernel: swappiness: 60 (default) cache-pressure: 100 (default)
ID-1: swap-1 type: zram size: 8 GiB used: 0 KiB (0.0%) priority: 100
dev: /dev/zram0
Sensors:
System Temperatures: cpu: N/A mobo: N/A gpu: amdgpu temp: 40.0 C
Fan Speeds (RPM): N/A
Info:
Processes: 375 Uptime: 11m wakeups: 1 Memory: 15.06 GiB
used: 3.1 GiB (20.6%) Init: systemd v: 249 runlevel: 5
target: graphical.target tool: systemctl Compilers: gcc: 11.2.1 Packages:
note: see --pkg flatpak: 43 Shell: Bash v: 5.1.8 running-in: terminator
inxi: 3.3.12
backlight service
❯ sudo systemctl start systemd-backlight@backlight
Job for systemd-backlight@backlight.service failed because the control process exited with error code.
See "systemctl status systemd-backlight@backlight.service" and "journalctl -xeu systemd-backlight@backlight.service" for details.
❯ sudo systemctl status systemd-backlight@backlight.service
× systemd-backlight@backlight.service - Load/Save Screen Backlight Brightness of backlight
Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
Active: failed (Result: exit-code) since Fri 2022-02-11 17:17:28 -03; 17s ago
Docs: man:systemd-backlight@.service(8)
Process: 4835 ExecStart=/usr/lib/systemd/systemd-backlight load backlight (code=exited, status=1/FAILURE)
Main PID: 4835 (code=exited, status=1/FAILURE)
CPU: 5ms
feb 11 17:17:28 fedora systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight...
feb 11 17:17:28 fedora systemd-backlight[4835]: Requires a subsystem and sysname pair specifying a backlight device.
feb 11 17:17:28 fedora systemd[1]: systemd-backlight@backlight.service: Main process exited, code=exited, status=1/FAILURE
feb 11 17:17:28 fedora systemd[1]: systemd-backlight@backlight.service: Failed with result 'exit-code'.
feb 11 17:17:28 fedora systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight.
❯ sudo journalctl -xeu systemd-backlight@backlight.service
[sudo] password for rscm:
░░ A start job for unit systemd-backlight@backlight.service has begun execution.
░░
░░ The job identifier is 2598.
feb 11 17:17:28 fedora systemd-backlight[4835]: Requires a subsystem and sysname pair specifying a backlight device.
feb 11 17:17:28 fedora systemd[1]: systemd-backlight@backlight.service: Main process exited, code=exited, status=1/FAILURE
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░
░░ An ExecStart= process belonging to unit systemd-backlight@backlight.service has exited.
░░
░░ The process' exit code is 'exited' and its exit status is 1.
feb 11 17:17:28 fedora systemd[1]: systemd-backlight@backlight.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░
░░ The unit systemd-backlight@backlight.service has entered the 'failed' state with result 'exit-code'.
feb 11 17:17:28 fedora systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight.
░░ Subject: A start job for unit systemd-backlight@backlight.service has failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░
░░ A start job for unit systemd-backlight@backlight.service has finished with a failure.
░░
░░ The job identifier is 2598 and the job result is failed.
lines 166-191/191 (END)