[PATCH v2 0/4] ASoC: meson: aiu: align I2S design to the AXG one

[Valerio Setti]

The goal of this series is to reshape Amlogic GX's AIU implementation for
I2S to let it follow the same design as in AXG's TDM. Keeping the same
design allows for unifying the two platform implementations in the future
and it also allows for an easy addition of I2S input.

The first commit introduces gx-formatter as the basic block which takes
care of properly formatting audio data. Formatters are DAPM widgets
(c.f. axg-tdm-formatter in AXG) which are dynamically attached/detached
to the streams when the latters starts/stop, respectively.
aiu-formatter-i2s is introduced as formatter implementation for the i2s
output.

By the end aiu-encoder-i2s will only need to handle interface clocks and
enforce interface wide rate symmetry (c.f axg-tdm-interface on the AXG
platform). Right now rate symmetry is not relevant because only i2s output
is supported, but it will become useful when following patch series will
introduce the i2s input part.

This series was tested on an OdroidC2 board (Amlogic S905 SOC) both with
HDMI output and with NXP SGTL5000 codec connected to the I2S pins.
This series was also verified using "pcm-test" test tool and all tests
are passing.

Changes in v2:
- Fixed most of the weaknesses found by Sashiko review tool [1].
- Resolved testing failures with "pcm-test" as reported by Mark Brown
  (thanks for the heads up!). I left a comment in
  "aiu_encoder_i2s_startup" to explain the fix.

Link to v1: https://lore.kernel.org/r/20260515-reshape-aiu-as-axg-v1-0-53b457784ff3@baylibre.com

[1]: https://sashiko.dev/#/patchset/20260515-reshape-aiu-as-axg-v1-0-53b457784ff3%40baylibre.com

Signed-off-by: Valerio Setti <vsetti at baylibre.com>
---
Valerio Setti (4):
      ASoC: meson: gx: add gx-formatter and gx-interface
      ASoC: meson: aiu-encoder-i2s: prepare for multiple streams
      ASoC: meson: aiu: introduce I2S output formatter
      ASoC: meson: aiu: use aiu-formatter-i2s to format I2S output data

 sound/soc/meson/Makefile            |   2 +
 sound/soc/meson/aiu-encoder-i2s.c   | 281 +++++++++++++++++++++++++----------
 sound/soc/meson/aiu-formatter-i2s.c | 104 +++++++++++++
 sound/soc/meson/aiu.c               |  32 +++-
 sound/soc/meson/aiu.h               |   4 +
 sound/soc/meson/gx-formatter.c      | 282 ++++++++++++++++++++++++++++++++++++
 sound/soc/meson/gx-formatter.h      |  56 +++++++
 sound/soc/meson/gx-interface.h      |  48 ++++++
 8 files changed, 731 insertions(+), 78 deletions(-)
---
base-commit: 254f49634ee16a731174d2ae34bc50bd5f45e731
change-id: 20260515-reshape-aiu-as-axg-1dac9037cad3

Best regards,
-- 
Valerio Setti <vsetti at baylibre.com>