Cirrus Logic CS4208 codec on MacBook9,1 (A1534): Getting speakers and suspend working on a MacBook9,1 with a Claude-written codec driver

A maintainer identified as Weegee directed Claude Opus 5.5 and Claude Sonnet 5.5 to write an out-of-tree DKMS kernel module that gives the Cirrus Logic CS4208 codec on the MacBook9,1 (A1534) working speaker and headphone routing and survives deep suspend, addressing a gap where mainline Linux has no quirk entry for the codec. The module routes four speaker channels through converter 0x0a to pin 0x1d at 44.1 kHz and 16 bits, handles headphones through converter 0x02 to pin 0x10 with hotplug in both directions, and activates only when the DMI string reads MacBook9,1 and the codec is a CS4208; ten commits carry a Claude Opus 5.5 trailer and nine carry Claude Sonnet 5.5. The project ships 336 hermetic tests requiring no root or hardware, but the headset microphone is not detected, install steps 3 to 5 were not re-run for the latest text revision, and the README warns readers to read the code before loading a kernel module as root.

Evidence at a glance Based on the linked sources. The author's reported result and independent confirmation are separate checks. - AI involvement - Reported models: Claude Opus 5.5, Claude Sonnet 5.5. Tools: DKMS, pacman/makepkg, ALSA HD-audio. The writeup below describes the work attributed to AI. - Reported result - Partial. This is the directory's source-based outcome classification. - Independent confirmation - Not reported. - Human work and limitations - The maintainer Weegee directed the work and ran hardware checks on a real MacBook9,1; those checks count only where docs/test-status.json records them. The README warns readers to read the code before loading a kernel module as root. The headset microphone does not work, and install steps 3 to 5 were not re-run for the latest text revision. Original sources What was done Mainline Linux has no quirk entry for the MacBook9,1 audio codec, so speakers stay silent. The maintainer had Claude write a DKMS module that adds the speaker and headphone routing and survives deep suspend. Mainline Linux has no entry for the CS4208 codec on the MacBook9,1 A1534 , so the generic HD-audio parser cannot bind a PCM to the speaker path, and after a suspend the speakers stay silent until a reboot. This repository packages an out-of-tree DKMS module for Arch-family distributions that fixes both problems. The README states that Claude wrote the project's code, tests and documentation while the maintainer gave directions and made the decisions. Ten commits carry a Claude Opus 5.5 trailer, nine carry Claude Sonnet 5.5, and the first public commit is described as a snapshot of earlier private history. The module routes four speaker channels through converter 0x0a to pin 0x1d at 44.1 kHz and 16 bits, handles headphones through converter 0x02 to pin 0x10 with hotplug in both directions, and activates only when the DMI string reads MacBook9,1 and the codec is a CS4208. The test directory holds 336 hermetic tests that need no root and no hardware. Hardware results are tracked in docs/test-status.json, and the README is explicit that steps not run for a given revision are marked as not run. A headset microphone is not detected. From the source Reproduce it On Arch or a derivative with dkms and kernel headers installed, download PKGBUILD, the install scriptlet, the source tarball and SHA256SUMS from the latest release into one directory, verify the checksums, run makepkg -si, reboot, then run macbook91-audio-verify. Removal is pacman -R macbook91-cs4208-dkms. Community Ask a question, share what worked, or follow the next milestone. Your library https://reversedwithai.com/library