DT510: TAA5412 (PCM6240) codec — backport/kernel path + SAI5 enable (Tier C2)

[ajlennon]

Parent tracking

Sub-issue of #2 (DT510 BSP bring-up plan).

Scope (Tier C2 — TAA5412 / PCM6240)

Enable the TAA5412 microphone codec on DT510 after TAS6424 is stable, including kernel ASoC support that is not in the factory-pinned linux-fslc 6.6.x tree today.

Facts (from investigation)

• Binding: ti,taa5412 is implemented in mainline sound/soc/codecs/pcm6240.c with CONFIG_SND_SOC_PCM6240 — present from Linux 6.10+, absent from current 6.6.52-class tree used for LmP.
• Hardware (SSOT): I2C2 0x51, SAI5 — not fully enabled in shipping DTS until driver + clock/pinctrl story is closed.

Deliverables

• Execute phased plan: vendor patches / kernel bump / out-of-tree — one change vector per phase (driver + build before turning codec okay in DT).
• Add CONFIG_SND_SOC_PCM6240=m (or agreed policy) + any firmware/coefficient handling per TI docs.
• Enable &sai5, taa5412@51, and simple-audio-card (or fsl-asoc) CPU ↔ codec path when ready.
• Acceptance: module loads, probe succeeds, capture path validated on hardware; rollback path documented.

Canonical plan (committed)

docs/DT510-TAA5412-PCM6240-BACKPORT-PLAN.md — phases A–F, naming (PCM6240, not “PCM6420”), risk and rollback.

Product order

Per #2 / plan: TAS6424 → TAA5412 → TAC5301 — do not enable all codecs in one DT change without a working slice between steps.

Assignees

Per parent #2: @ajlennon @ohull456