HP Pavilion Gaming laptop 15-ec1002ur; AMD Ryzen 5 4600H; Gentoo, Cinnamon-5.6.0; Details about system: https://linux-hardware.org/?probe=7aa00b2d9f Display backlight function is controlled by Fn+F2 (backlight down) and Fn+F3 (backlight up) key sequences. No need any configuration for set up key sequences - they are worked natively in X subsystem (Cinnamon, KDE, Gnome). acpid daemon not configured to use those key-sequences. kernel 6.1.3 - backlight worked: > # find /sys -name "*backlight*" > /sys/class/backlight > /sys/devices/pci0000:00/0000:00:08.1/0000:05:00.0/backlight > /sys/bus/platform/drivers/pwm-backlight > /sys/module/video/parameters/register_backlight_delay > /sys/module/amdgpu/parameters/backlight kernel 6.1.5, 6.1.6 and 6.1.7 - backlight not worked: > # find /sys -name "*backlight*" > /sys/class/backlight > /sys/bus/platform/drivers/pwm-backlight > /sys/module/video/parameters/register_backlight_delay > /sys/module/amdgpu/parameters/backlight E.g.: backlight device not found. Press any of Fn+F2 or Fn+F3 key sequence produce messages in syslog: > kernel: atkbd serio0: Unknown key pressed (translated set 2, code 0xab on > isa0060/serio0). > kernel: atkbd serio0: Use 'setkeycodes e02b <keycode>' to make it known. > pkexec[24931]: pam_unix(polkit-1:session): session opened for user > root(uid=0) by (uid=1000) > pkexec[24931]: username: Executing command [USER=root] [TTY=unknown] > [CWD=/home/username] [COMMAND=/usr/libexec/csd-backlight-helper > --set-brightness 88 -b firmware -b platform -b raw] > kernel: atkbd serio0: Unknown key released (translated set 2, code 0xab on > isa0060/serio0). > kernel: atkbd serio0: Use 'setkeycodes e02b <keycode>' to make it known.
Syslog messages are generated in any case, regardless of the availability of the backlight device: both in 6.1.3 and at 6.1.5+. But backlight level is changed only if backlight device is present in the system (6.1.3). Backlight level stay at 100% (maximum), if backlight device dows not found in system (6.1.5 and above). At 100% level of backlight, the eyes are damaged by high intensity of the led light. I do not test the kernel 6.1.4. I think that the backlighting device was not found in my system, and the link at /sys/devices/pci0000:00/0000:00:08.1/0000:05:00.0/backlight path was not created using this function added to the kernel 6.1.4 or 6.1.5: For kernel 6.1.4: > $ curl -s https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.1.4 | grep > -i -B 8 -A 6 backlight | grep -A 5 ^commit >commit 8af3d02aae3ecc23ee84d7078d1ebb3df7557dda >Author: Hans de Goede <hdegoede@redhat.com> >Date: Mon Nov 14 15:44:59 2022 +0100 > > ACPI: video: Prefer native over vendor > >-- >commit 923c1922bdbe44bdbebe57b5b976d40f68853653 >Author: Hans de Goede <hdegoede@redhat.com> >Date: Mon Nov 14 15:44:58 2022 +0100 > > ACPI: video: Simplify __acpi_video_get_backlight_type() For kernel 6.1.5: > $ curl -s https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.1.5 | grep > -i -B 8 -A 7 backlight | grep -A 5 ^commit >commit 9c152189a7e85dac1f759d6ba95f877af91ccf8c >Author: Mario Limonciello <mario.limonciello@amd.com> >Date: Thu Dec 8 10:42:07 2022 -0600 > > ACPI: video: Don't enable fallback path for creating ACPI backlight by > default > >-- >commit adaf41b56803fe7a9a4ac625c7e41615ef23591f >Author: Mario Limonciello <mario.limonciello@amd.com> >Date: Thu Dec 8 10:42:06 2022 -0600 > > drm/amd/display: Report to ACPI video if no panels were found > >-- >commit 0ba8892d86ad69775e4ee3de53b021ae33aca8c0 >Author: Mario Limonciello <mario.limonciello@amd.com> >Date: Thu Dec 8 10:42:05 2022 -0600 > > ACPI: video: Allow GPU drivers to report no panels
Please repost here: https://gitlab.freedesktop.org/drm/amd/-/issues
But reported: https://gitlab.freedesktop.org/drm/amd/-/issues/2361
Artem, thank you for all the kernel bugzilla triaging work you do, this is much appreciated. For future backlight bugs, please just Cc me (I use jwrdegoede@fedoraproject.org here) instead of forwarding people to the drm-driver bug-tracker. Often these bugs have to do with the heuristics for picking which (acpi_video / vendor / GPU-native) backlight driver to use and those heuristics are maintained by me. Note, since this has been forwarded to the amd-gpu drm tracker at gitlab.freedesktop, lets continue discussing the actual bug there.