In Fedora 32 Silverblue on IdeaPad 5 15ARE05 the backlight does not seem to be correctly handled/restored.
Problems:
- it is very bright (though I’m not sure whether this is intended)
- it often/always(?) does not restore the backlight at boot (it juses uses the highest brightness instead)
- I can basically adjust it and see a difference, but the +/- slider is not “smooth” and it only seem to have 19 steps or so.
CPU: AMD Ryzen 7 4800U
GPU: AMD Renoir
$ systemctl status systemd-backlight@backlight
● systemd-backlight@backlight.service - Load/Save Screen Backlight Brightness of backlight
Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static; vendor preset: disabled)
Active: inactive (dead)
Docs: man:systemd-backlight@.service(8)
Also here some interesting logs:
Jun 04 23:58:40 systemd-backlight[1118]: amdgpu_bl0: Saved brightness 2 too low; increasing to 12.
Jun 04 23:58:40 audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=systemd-backlight@backlight:amdgpu_bl0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
[…]
Jun 04 13:37:53 systemd[1]: Created slice system-systemd\x2dbacklight.slice.
Jun 04 13:37:54 systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:amdgpu_bl0...
Jun 04 13:37:54 systemd[1127]: systemd-backlight@backlight:amdgpu_bl0.service: Failed to set up special execution directory in /var/lib: Read-only file system
Jun 04 13:37:54 systemd[1127]: systemd-backlight@backlight:amdgpu_bl0.service: Failed at step STATE_DIRECTORY spawning /usr/lib/systemd/systemd-backlight: Read-only file system
Jun 04 13:37:54 systemd[1]: systemd-backlight@backlight:amdgpu_bl0.service: Main process exited, code=exited, status=238/STATE_DIRECTORY
Jun 04 13:37:54 systemd[1]: systemd-backlight@backlight:amdgpu_bl0.service: Failed with result 'exit-code'.
Jun 04 13:37:54 systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:amdgpu_bl0.
Jun 04 13:37:54 audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg='unit=systemd-backlight@backlight:amdgpu_bl0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=failed'
What’s also very strange:
I can cat /var/lib/systemd/backlight/pci-0000\:03\:00.0\:backlight\:amdgpu_bl0 and always get 12.
No matter, what brightness level the screen currently has.
$ ls /sys/class/backlight/amdgpu_bl0/*
/sys/class/backlight/amdgpu_bl0/actual_brightness
/sys/class/backlight/amdgpu_bl0/bl_power
/sys/class/backlight/amdgpu_bl0/brightness
/sys/class/backlight/amdgpu_bl0/max_brightness
/sys/class/backlight/amdgpu_bl0/scale
/sys/class/backlight/amdgpu_bl0/type
/sys/class/backlight/amdgpu_bl0/uevent
/sys/class/backlight/amdgpu_bl0/device:
ari_enabled modalias
backlight msi_bus
boot_vga msi_irqs
broken_parity_status numa_node
class pcie_replay_count
config power
consistent_dma_mask_bits power_dpm_force_performance_level
current_link_speed power_dpm_state
current_link_width pp_cur_state
d3cold_allowed pp_dpm_dcefclk
device pp_dpm_fclk
dma_mask_bits pp_dpm_mclk
driver pp_dpm_pcie
driver_override pp_dpm_sclk
drm pp_dpm_socclk
enable pp_force_state
firmware_node pp_mclk_od
fw_version pp_num_states
gpu_busy_percent pp_power_profile_mode
graphics pp_sclk_od
hwmon pp_table
i2c-2 remove
i2c-4 rescan
i2c-5 reset
iommu resource
iommu_group resource0
irq resource0_wc
link resource2
local_cpulist resource2_wc
local_cpus resource4
max_link_speed resource5
max_link_width revision
mem_info_gtt_total subsystem
mem_info_gtt_used subsystem_device
mem_info_vis_vram_total subsystem_vendor
mem_info_vis_vram_used uevent
mem_info_vram_total vbios_version
mem_info_vram_used vendor
mem_info_vram_vendor
/sys/class/backlight/amdgpu_bl0/power:
autosuspend_delay_ms runtime_active_time runtime_suspended_time
control runtime_status
/sys/class/backlight/amdgpu_bl0/subsystem:
amdgpu_bl0
$ grep ^ /dev/null *
actual_brightness:22102
bl_power:0
brightness:86
grep: device: Ist ein Verzeichnis
max_brightness:255
grep: power: Ist ein Verzeichnis
scale:unknown
grep: subsystem: Ist ein Verzeichnis
type:raw
$ cd /sys/class/backlight/amdgpu_bl0/power
$ grep ^ /dev/null *
grep: autosuspend_delay_ms: Eingabe-/Ausgabefehler
control:auto
runtime_active_time:0
runtime_status:unsupported
runtime_suspended_time:0
Interestingly the things in /sys/class/backlight/amdgpu_bl0 seem to “work”.
This is the data reported at lowest brightness:
$ grep ^ /dev/null *
actual_brightness:514
bl_power:0
brightness:2
grep: device: Ist ein Verzeichnis
max_brightness:255
grep: power: Ist ein Verzeichnis
scale:unknown
grep: subsystem: Ist ein Verzeichnis
type:raw
And this at highest brightness:
$ grep ^ /dev/null *
actual_brightness:65535
bl_power:0
brightness:255
grep: device: Ist ein Verzeichnis
max_brightness:255
grep: power: Ist ein Verzeichnis
scale:unknown
grep: subsystem: Ist ein Verzeichnis
type:raw
Where can I report this?
Or is there a workaround?
I’ve seen similar issues
Is this a systemd error? Or does systemd-backlight only save/store the current value?