Public bug reported:
Brightness control does not work on my laptop in Ubuntu 24.04.
Hardware:
- Intel HD Graphics 620 (Kaby Lake)
- AMD Radeon R7 M265/M365X/M465 hybrid graphics
- Internal display: eDP-1
Ubuntu:
- Ubuntu 24.04
- Kernel: 7.0.0-28-generic
- GNOME 46
The brightness keys do not change the physical screen brightness.
The system exposes:
/sys/class/backlight/intel_backlight
brightnessctl detects:
Device 'intel_backlight'
Current brightness: 1023
Max brightness: 1023
I can change the value with:
sudo brightnessctl set 50%
The value changes correctly in sysfs:
actual_brightness = 517
brightness = 517
However, the physical brightness of the screen does NOT change.
The display is:
card1-eDP-1
status: connected
enabled: enabled
The i915 driver is loaded and initializes the internal display
correctly.
The AMD GPU is also detected through hybrid graphics / vga_switcheroo.
IMPORTANT:
The exact same laptop works correctly under Fedora 44 with GNOME 50. The
brightness controls physically change the screen brightness there.
Expected behavior:
Changing brightness with the brightness keys or the GNOME brightness control
should physically change the laptop screen brightness.
Actual behavior:
The brightness value changes in sysfs/brightnessctl, but the physical screen
brightness remains unchanged.
Nb :
# Rapport d’informations du système
---
## Détails du compte rendu
- **Date de génération :** 2026-08-15 04:35:58
## Informations liées au matériel :
- **Modèle du matériel :** HP HP ZBook 15u G4
- **Mémoire :** 16,0 Gio
- **Processeur :** Intel® Core™ i7-7500U × 4
- **Carte graphique :** Intel® HD Graphics 620 (KBL
GT2)
- **Carte graphique 1 :** AMD Radeon™ R7 M350
- **Capacité du disque :** 512,1 Go
## Informations liées au logiciel :
- **Version du micrologiciel :** P78 Ver. 01.06
- **Nom du système d’exploitation :** Ubuntu 24.04.4 LTS
- **Construction du système d’exploitation :** (null)
- **Type de système d’exploitation :** 64 bits
- **Version de GNOME :** 46
- **Système de fenêtrage :** Wayland
- **Version du noyau :** Linux 7.0.0-28-generic
ProblemType: Bug
DistroRelease: Ubuntu 24.04
Package: linux-image-7.0.0-28-generic 7.0.0-28.28~24.04.1
ProcVersionSignature: Ubuntu 7.0.0-28.28~24.04.1-generic 7.0.12
Uname: Linux 7.0.0-28-generic x86_64
ApportVersion: 2.28.3-0ubuntu0.1
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: seb 2926 F.... wireplumber
/dev/snd/seq: seb 2921 F.... pipewire
CRDA: N/A
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Sat Aug 15 04:29:48 2026
InstallationDate: Installed on 2026-02-04 (192 days ago)
InstallationMedia: Ubuntu 24.04.3 LTS "Noble Numbat" - Release amd64
(20250805.1)
MachineType: HP HP ZBook 15u G4
ProcEnviron:
LANG=fr_FR.UTF-8
PATH=(custom, no user)
SHELL=/bin/bash
TERM=xterm-256color
XDG_RUNTIME_DIR=<set>
ProcFB: 0 i915drmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-28-generic
root=UUID=f113e742-5386-41da-afdc-fc0c0f304184 ro quiet splash
RelatedPackageVersions:
linux-restricted-modules-7.0.0-28-generic N/A
linux-backports-modules-7.0.0-28-generic N/A
linux-firmware 20240318.git3b128b60-0ubuntu2.29
SourcePackage: linux-hwe-7.0
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/12/2017
dmi.bios.release: 1.6
dmi.bios.vendor: HP
dmi.bios.version: P78 Ver. 01.06
dmi.board.name: 828C
dmi.board.vendor: HP
dmi.board.version: KBC Version 45.39
dmi.chassis.asset.tag: 5CG738451W
dmi.chassis.type: 10
dmi.chassis.vendor: HP
dmi.ec.firmware.release: 69.57
dmi.modalias:
dmi:bvnHP:bvrP78Ver.01.06:bd07/12/2017:br1.6:efr69.57:svnHP:pnHPZBook15uG4:pvr:rvnHP:rn828C:rvrKBCVersion45.39:cvnHP:ct10:cvr:skuY6K01ET#ABF:pfa103C_5336ANHPEliteBook:
dmi.product.family: 103C_5336AN HP EliteBook
dmi.product.name: HP ZBook 15u G4
dmi.product.sku: Y6K01ET#ABF
dmi.sys.vendor: HP
modified.conffile..etc.default.apport: [modified]
mtime.conffile..etc.default.apport: 2026-04-07T18:50:30.094624
** Affects: linux-hwe-7.0 (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug noble wayland-session
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https://bugs.launchpad.net/bugs/2163556
Title:
Brightness control does not affect screen on Intel HD Graphics 620 /
AMD hybrid laptop
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