Update: I performed an extensive diagnostic test on my iMac 27" (2017), equipped with an AMDGPU graphics card and a Cirrus Logic CS8409 audio chip, running Ubuntu 24.04.2 LTS with Wayland.
System configuration: OS: Ubuntu 24.04.2 LTS, Wayland Kernel: 6.11.0-29-generic Graphics: AMDGPU 25.10.1 (official driver from AMD) Audio: CS8409, compiled manually from GitHub Findings: ALSA detects the CS8409 as card 0 (aplay -l), and the device works properly. PipeWire correctly recognizes the mixer and nodes (pw-dump confirms CS8409/CS42L83 detection). PulseAudio lists the output as alsa_output.pci-0000_00_1f.3.analog- stereo, driven via PipeWire and using the CS8409 mixer. The kernel module snd_hda_codec_cs8409 is loaded (lsmod), and dmesg confirms autoconfiguration for line outs, headphone outs, and internal mics. The system has the latest headers installed: linux- headers-6.11.0-29-generic and linux-headers-generic-hwe-24.04, matching the active kernel — no legacy packages were needed. Note: The CS8409 driver must be compiled manually and breaks after kernel updates unless recompiled. This clearly shows the need to integrate the driver into either alsa-ucm-conf or the mainline Linux kernel. Modern Ubuntu systems are fully capable of supporting it without older headers — the only missing piece is native module inclusion. Additional note (graphics): To ensure proper graphical performance on iMac 27" (2017) with AMD Radeon GPUs, I highly recommend that AMDGPU drivers be prioritized in kernel-level integration. When I installed AMDGPU 25.10.1 for Ubuntu 24.04.2, the system instantly detected native 5K resolution without any manual configuration. Mesa fallback drivers caused incorrect resolution detection and had a negative impact on audio subsystem behavior. Using AMDGPU significantly improves both graphical and system stability. Recommendation: Please consider adding native support for the CS8409 codec into alsa-ucm-conf or the Linux kernel. Additionally, prioritize AMDGPU over Mesa drivers when detecting Apple hardware during OS setup. These changes would ensure reliable functionality across graphics and audio systems for affected users. Thank you for your work! -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to alsa-driver in Ubuntu. https://bugs.launchpad.net/bugs/2114760 Title: Missing drivers for Cirrus Logic CS8409 and AMDGPU on iMac 27" (2017) 5K Status in alsa-driver package in Ubuntu: New Status in alsa-ucm-conf package in Ubuntu: New Bug description: Subject: Missing drivers for Cirrus Logic CS8409 and AMDGPU on iMac 27" (2017) 5K Dear Ubuntu OS Team, I am using Ubuntu 24.04.02 on an iMac 27" (2017) 5K and have encountered issues with the Cirrus Logic CS8409 audio chip. Alsa, PulseAudio, and Pipewire are unable to properly utilize it. I found a driver on GitHub (github.com/egorenar/snd-hda-codec-cs8409), but it requires outdated headers, making it impossible to install. AMDGPU Issues: During system installation, the display appears in a tiny interface. While it works fine after changing the resolution, navigating such an interface is extremely difficult. It is unclear which resolution is correct for this iMac model. Audio Issues: There is no sound during installation, after installation, or even after system updates. The sound settings only show "Dummy Output", with no available audio devices. When I attempt to install the driver using: sudo apt install linux-headers-generic sudo apt install build-essential git gcc-12 the driver gets uninstalled after a system update, or the sound stops working entirely—forcing me to repeat the process from scratch. It seems that PulseAudio, ALSA, and Pipewire conflict with the Cirrus Logic CS8409 chip. I would like to ask if there is a solution to this issue or whether a fix could be included in an upcoming Ubuntu OS update or package release. Thank you for your help and for the great work on Ubuntu! Best regards, Marek ProblemType: Bug DistroRelease: Ubuntu 24.04 Package: alsa-base 1.0.25+dfsg-0ubuntu7 ProcVersionSignature: Ubuntu 6.8.0-60.63~22.04.1-generic 6.8.12 Uname: Linux 6.8.0-60-generic x86_64 ApportVersion: 2.20.11-0ubuntu82.8 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/seq: mahav 1315 F.... pipewire /dev/snd/controlC1: mahav 1317 F.... wireplumber /dev/snd/controlC0: mahav 1317 F.... wireplumber CasperMD5CheckResult: pass CurrentDesktop: zorin:GNOME Date: Mon Jun 16 20:08:10 2025 InstallationDate: Installed on 2025-06-01 (15 days ago) InstallationMedia: Zorin-OS 17.3 Core 64bit PackageArchitecture: all PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. SourcePackage: alsa-driver UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 06/23/2024 dmi.bios.release: 0.1 dmi.bios.vendor: Apple Inc. dmi.bios.version: 529.140.2.0.0 dmi.board.name: Mac-BE088AF8C5EB4FA2 dmi.board.vendor: Apple Inc. dmi.board.version: iMac18,3 dmi.chassis.type: 9 dmi.chassis.vendor: Apple Inc. dmi.chassis.version: Mac-BE088AF8C5EB4FA2 dmi.modalias: dmi:bvnAppleInc.:bvr529.140.2.0.0:bd06/23/2024:br0.1:svnAppleInc.:pniMac18,3:pvr1.0:rvnAppleInc.:rnMac-BE088AF8C5EB4FA2:rvriMac18,3:cvnAppleInc.:ct9:cvrMac-BE088AF8C5EB4FA2:sku: dmi.product.family: iMac dmi.product.name: iMac18,3 dmi.product.version: 1.0 dmi.sys.vendor: Apple Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/2114760/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
