[PATCH v3 0/2] ASoC: codecs: add Texas Instruments TAS2557 smart amplifier driver

[Gianluca Boiano <morf3089@gmail.com>]

The TAS2557 is a mono Class-D smart amplifier with an on-chip DSP for
speaker protection, controlled over I2C with audio carried over
I2S/TDM.  The DSP requires a board-specific firmware image generated
with TI's PurePath Console tuning tools; without it the device passes
no audio.

Patch 1 adds the devicetree binding.  Patch 2 adds the ASoC codec
driver.  A single node manages one physical TAS2557, or two of them
sharing one ASI bus and one reset/IRQ pair, using the reg-array
convention of ti,tas2781.yaml: the device at reg index 0 is DEV_A and
the device at index 1 is DEV_B, so no channel-selection property is
needed.  The driver covers mono and dual-device stereo operation and
fault-interrupt recovery that reloads the firmware configuration on
clock loss, over-current, brownout or over-temperature.

The driver has been exercised across development of this series in
mono configuration on Xiaomi Mi A2 (SDM660, jasmine), Xiaomi Redmi
Note 6 Pro (SDM636, tulip) and Xiaomi Redmi 5 Plus (MSM8953, vince),
driving the top speaker, and in dual-device stereo on Xiaomi Mi Pad 4
(SDM660, clover).  The v3 ASI word-length and data-slot-offset
changes follow hardware reports from vince (16-bit, offset 0) and
have not yet been re-confirmed on the 32-bit/offset-1 boards above.

Changes in v3:
- rework the binding and driver to a single-node, reg-array model
  that manages up to two devices, matching ti,tas2781.yaml; drop the
  ti,channel property entirely and derive DEV_A/DEV_B tuning from the
  device order in reg (Krzysztof Kozlowski)
- rename ti,imon-slot-no/ti,vmon-slot-no to the plural
  ti,imon-slot-nos/ti,vmon-slot-nos arrays (one entry per reg entry),
  and constrain firmware-name to maxItems: 1 (Krzysztof Kozlowski)
- derive the ASI word length from the stream (params_width) and
  re-apply it after each reset instead of hardcoding 32-bit, so
  16-bit boards are no longer forced to 32-bit
- set symmetric_rate on the DAI (Mark Brown), and add
  symmetric_sample_bits since one firmware config (one rate) is
  active at a time and playback and capture share the single ASI
  word length
- apply the same write-then-cache ordering used for the DAC-gain
  control to the ISENSE/VSENSE mixer setters, so a failed
  POWER_CTRL2 write no longer leaves the cached enable state stale
- only cache the DAC gain after the hardware write succeeds, so a
  failed write no longer leaves the cache out of sync (Mark Brown)
- default the ASI data-slot offset to 0; an explicit
  snd_soc_dai_set_tdm_slot() still takes precedence

Changes in v2:
- add the four mandatory supplies (vbat/iovdd/avdd/dvdd) to the
  devicetree binding's "required" list (Wang Sen)
- propagate register-write failures out of hw_params() instead of
  only logging them (Wang Sen)
- return IRQ_NONE instead of IRQ_HANDLED from the fault interrupt
  handler when the device isn't in a state to have raised it, so
  shared-IRQ accounting stays correct (Mark Brown)
- re-apply cached runtime state (DAI format, sense enables, DAC gain,
  ASI slot offsets) after every device reset, including fault
  recovery, instead of letting a hardcoded startup sequence silently
  override set_dai_fmt()/the ISENSE/VSENSE mixer controls (Mark Brown)
- honour explicit snd_soc_dai_set_tdm_slot() configuration in
  hw_params, and restore TX (OFFSET2) slot offsets after reset
- wait for the asynchronous firmware load on first stream start
  instead of failing with -ENODEV
- make mute_stream direction-aware so capture-only IV-sense streams
  are unmuted and stopping playback no longer mutes a live capture

Link to v2: https://lore.kernel.org/linux-sound/20260711145722.188556-1-morf3089@gmail.com/
Link to v1: https://lore.kernel.org/linux-sound/20260709221331.989109-1-morf3089@gmail.com/

Gianluca Boiano (2):
  dt-bindings: sound: add Texas Instruments TAS2557
  ASoC: codecs: add TAS2557 mono smart amplifier driver

 .../devicetree/bindings/sound/ti,tas2557.yaml |  174 +
 MAINTAINERS                                   |    1 +
 sound/soc/codecs/Kconfig                      |   11 +
 sound/soc/codecs/Makefile                     |    2 +
 sound/soc/codecs/tas2557.c                    | 3067 +++++++++++++++++
 sound/soc/codecs/tas2557.h                    |  228 ++
 6 files changed, 3483 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/ti,tas2557.yaml
 create mode 100644 sound/soc/codecs/tas2557.c
 create mode 100644 sound/soc/codecs/tas2557.h


base-commit: a13c140cc289c0b7b3770bce5b3ad42ab35074aa
-- 
2.55.0