FW13 AMD AI 300 BIOS falsely exposes AMD ACP in ACPI tables creating phantom device

[d-goldin]

Device Information

System Model or SKU

Please select one of the following

• Framework Laptop 13 (AMD Ryzen™ AI 300 Series)
• [?] Framework Laptop 16 (AMD Ryzen™ AI 300 Series)
• [?] Framework Desktop (AMD Ryzen™ AI 300 PRO Series)

I strongly suspect FW16 AI 300 has the same issue, but have no hardware to verify.

BIOS VERSION

0.0.3.5

Describe the bug

The BIOS ACPI tables contain an entry for AMD ACP, which in reality is not wired up. This causes the Linux kernel driver to believe the interface really exists, creating a phantom interface, further confusing ALSA UCM.

Expected behavior

The ACPI table should not contain an entry for AMD ACP.

Operating System

NixOS 25.11, Kernel 6.18.6, but should affect all recent kernels.

Additional context

This thread includes more information and some advice from the ALSA maintainer: NixOS/nixos-hardware#1603

This particular comment includes dumps of the ACPI tables: NixOS/nixos-hardware#1603 (comment)