ASoC: meson: aiu: align I2S design to the AXG one

Valerio Setti <vsetti@baylibre.com> says:

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.

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

Link: https://patch.msgid.link/20260610-reshape-aiu-as-axg-v2-0-cac3663a8b51@baylibre.com

8 files changed, 731 insertions, 78 deletions

diff --git a/sound/soc/meson/Makefile b/sound/soc/meson/Makefile
index 24078e4396b0..f9ec0ebb01f0 100644
--- a/sound/soc/meson/Makefile
+++ b/sound/soc/meson/Makefile
@@ -4,6 +4,8 @@ snd-soc-meson-aiu-y := aiu.o
 snd-soc-meson-aiu-y += aiu-acodec-ctrl.o
 snd-soc-meson-aiu-y += aiu-codec-ctrl.o
 snd-soc-meson-aiu-y += aiu-encoder-i2s.o
+snd-soc-meson-aiu-y += gx-formatter.o
+snd-soc-meson-aiu-y += aiu-formatter-i2s.o
 snd-soc-meson-aiu-y += aiu-encoder-spdif.o
 snd-soc-meson-aiu-y += aiu-fifo.o
 snd-soc-meson-aiu-y += aiu-fifo-i2s.o
diff --git a/sound/soc/meson/aiu-encoder-i2s.c b/sound/soc/meson/aiu-encoder-i2s.c
index 3b4061508c18..83b579e98f1c 100644
--- a/sound/soc/meson/aiu-encoder-i2s.c
+++ b/sound/soc/meson/aiu-encoder-i2s.c
@@ -10,14 +10,11 @@
 #include <sound/soc-dai.h>
 
 #include "aiu.h"
+#include "gx-formatter.h"
+#include "gx-interface.h"
 
-#define AIU_I2S_SOURCE_DESC_MODE_8CH	BIT(0)
-#define AIU_I2S_SOURCE_DESC_MODE_24BIT	BIT(5)
-#define AIU_I2S_SOURCE_DESC_MODE_32BIT	BIT(9)
 #define AIU_I2S_SOURCE_DESC_MODE_SPLIT	BIT(11)
-#define AIU_RST_SOFT_I2S_FAST		BIT(0)
 
-#define AIU_I2S_DAC_CFG_MSB_FIRST	BIT(2)
 #define AIU_CLK_CTRL_I2S_DIV_EN		BIT(0)
 #define AIU_CLK_CTRL_I2S_DIV		GENMASK(3, 2)
 #define AIU_CLK_CTRL_AOCLK_INVERT	BIT(6)
@@ -35,49 +32,6 @@ static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component,
 				      enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0);
 }
 
-static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component,
-				      struct snd_pcm_hw_params *params)
-{
-	/* Always operate in split (classic interleaved) mode */
-	unsigned int desc = AIU_I2S_SOURCE_DESC_MODE_SPLIT;
-
-	/* Reset required to update the pipeline */
-	snd_soc_component_write(component, AIU_RST_SOFT, AIU_RST_SOFT_I2S_FAST);
-	snd_soc_component_read(component, AIU_I2S_SYNC);
-
-	switch (params_physical_width(params)) {
-	case 16: /* Nothing to do */
-		break;
-
-	case 32:
-		desc |= (AIU_I2S_SOURCE_DESC_MODE_24BIT |
-			 AIU_I2S_SOURCE_DESC_MODE_32BIT);
-		break;
-
-	default:
-		return -EINVAL;
-	}
-
-	switch (params_channels(params)) {
-	case 2: /* Nothing to do */
-		break;
-	case 8:
-		desc |= AIU_I2S_SOURCE_DESC_MODE_8CH;
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	snd_soc_component_update_bits(component, AIU_I2S_SOURCE_DESC,
-				      AIU_I2S_SOURCE_DESC_MODE_8CH |
-				      AIU_I2S_SOURCE_DESC_MODE_24BIT |
-				      AIU_I2S_SOURCE_DESC_MODE_32BIT |
-				      AIU_I2S_SOURCE_DESC_MODE_SPLIT,
-				      desc);
-
-	return 0;
-}
-
 static int aiu_encoder_i2s_set_legacy_div(struct snd_soc_component *component,
 					  struct snd_pcm_hw_params *params,
 					  unsigned int bs)
@@ -112,6 +66,9 @@ static int aiu_encoder_i2s_set_more_div(struct snd_soc_component *component,
 					struct snd_pcm_hw_params *params,
 					unsigned int bs)
 {
+	struct aiu *aiu = snd_soc_component_get_drvdata(component);
+	struct gx_iface *iface = &aiu->i2s.iface;
+
 	/*
 	 * NOTE: this HW is odd.
 	 * In most configuration, the i2s divider is 'mclk / blck'.
@@ -126,6 +83,18 @@ static int aiu_encoder_i2s_set_more_div(struct snd_soc_component *component,
 			return -EINVAL;
 		}
 		bs += bs / 2;
+		iface->bs_quirk = true;
+	} else {
+		/*
+		 * If the bs quirk is currently applied for one stream and another
+		 * ones tries to setup a configuration for which the quirk is
+		 * not required, then fail.
+		 */
+		if (iface->bs_quirk) {
+			dev_err(component->dev,
+				"bclk requirements are incompatible with active stream\n");
+			return -EINVAL;
+		}
 	}
 
 	/* Use CLK_MORE for mclk to bclk divider */
@@ -145,21 +114,17 @@ static int aiu_encoder_i2s_set_clocks(struct snd_soc_component *component,
 				      struct snd_pcm_hw_params *params)
 {
 	struct aiu *aiu = snd_soc_component_get_drvdata(component);
+	struct gx_iface *iface = &aiu->i2s.iface;
 	unsigned int srate = params_rate(params);
 	unsigned int fs, bs;
 	int ret;
 
 	/* Get the oversampling factor */
-	fs = DIV_ROUND_CLOSEST(clk_get_rate(aiu->i2s.clks[MCLK].clk), srate);
+	fs = DIV_ROUND_CLOSEST(iface->mclk_rate, srate);
 
-	if (fs % 64)
+	if ((fs % 64) || (fs == 0))
 		return -EINVAL;
 
-	/* Send data MSB first */
-	snd_soc_component_update_bits(component, AIU_I2S_DAC_CFG,
-				      AIU_I2S_DAC_CFG_MSB_FIRST,
-				      AIU_I2S_DAC_CFG_MSB_FIRST);
-
 	/* Set bclk to lrlck ratio */
 	snd_soc_component_update_bits(component, AIU_CODEC_DAC_LRCLK_CTRL,
 				      AIU_CODEC_DAC_LRCLK_CTRL_DIV,
@@ -188,24 +153,53 @@ static int aiu_encoder_i2s_hw_params(struct snd_pcm_substream *substream,
 				     struct snd_pcm_hw_params *params,
 				     struct snd_soc_dai *dai)
 {
+	struct gx_stream *ts = snd_soc_dai_get_dma_data(dai, substream);
+	struct gx_iface *iface = ts->iface;
 	struct snd_soc_component *component = dai->component;
 	int ret;
 
-	/* Disable the clock while changing the settings */
-	aiu_encoder_i2s_divider_enable(component, false);
-
-	ret = aiu_encoder_i2s_setup_desc(component, params);
-	if (ret) {
-		dev_err(dai->dev, "setting i2s desc failed\n");
-		return ret;
+	/*
+	 * Enforce interface wide rate symmetry only if there is more than
+	 * 1 stream active.
+	 */
+	if (snd_soc_dai_active(dai) > 1) {
+		if (iface->rate && iface->rate != params_rate(params)) {
+			dev_err(dai->dev, "can't set iface rate (%d != %d)\n",
+				iface->rate, params_rate(params));
+			return -EINVAL;
+		}
 	}
 
 	ret = aiu_encoder_i2s_set_clocks(component, params);
 	if (ret) {
-		dev_err(dai->dev, "setting i2s clocks failed\n");
+		dev_err(dai->dev, "setting i2s clocks failed: %d\n", ret);
 		return ret;
 	}
 
+	iface->rate = params_rate(params);
+	ts->physical_width = params_physical_width(params);
+	ts->width = params_width(params);
+	ts->channels = params_channels(params);
+
+	return 0;
+}
+
+static int aiu_encoder_i2s_prepare(struct snd_pcm_substream *substream,
+				   struct snd_soc_dai *dai)
+{
+	struct gx_stream *ts = snd_soc_dai_get_dma_data(dai, substream);
+	struct snd_soc_component *component = dai->component;
+	int ret;
+
+	if (ts->clk_enabled)
+		return 0;
+
+	ret = clk_prepare_enable(ts->iface->mclk);
+	if (ret)
+		return ret;
+
+	ts->clk_enabled = true;
+
 	aiu_encoder_i2s_divider_enable(component, true);
 
 	return 0;
@@ -214,9 +208,24 @@ static int aiu_encoder_i2s_hw_params(struct snd_pcm_substream *substream,
 static int aiu_encoder_i2s_hw_free(struct snd_pcm_substream *substream,
 				   struct snd_soc_dai *dai)
 {
+	struct gx_stream *ts = snd_soc_dai_get_dma_data(dai, substream);
+	struct gx_iface *iface = ts->iface;
 	struct snd_soc_component *component = dai->component;
 
-	aiu_encoder_i2s_divider_enable(component, false);
+	/*
+	 * If this is the last substream being closed then disable the i2s
+	 * clock divider and clear 'iface->rate'.
+	 */
+	if (snd_soc_dai_active(dai) <= 1) {
+		aiu_encoder_i2s_divider_enable(component, 0);
+		iface->rate = 0;
+		iface->bs_quirk = false;
+	}
+
+	if (ts->clk_enabled) {
+		clk_disable_unprepare(ts->iface->mclk);
+		ts->clk_enabled = false;
+	}
 
 	return 0;
 }
@@ -224,6 +233,8 @@ static int aiu_encoder_i2s_hw_free(struct snd_pcm_substream *substream,
 static int aiu_encoder_i2s_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
 {
 	struct snd_soc_component *component = dai->component;
+	struct aiu *aiu = snd_soc_component_get_drvdata(component);
+	struct gx_iface *iface = &aiu->i2s.iface;
 	unsigned int inv = fmt & SND_SOC_DAIFMT_INV_MASK;
 	unsigned int val = 0;
 	unsigned int skew;
@@ -255,9 +266,12 @@ static int aiu_encoder_i2s_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
 		skew = 0;
 		break;
 	default:
+		dev_err(dai->dev, "unsupported dai format\n");
 		return -EINVAL;
 	}
 
+	iface->fmt = fmt;
+
 	val |= FIELD_PREP(AIU_CLK_CTRL_LRCLK_SKEW, skew);
 	snd_soc_component_update_bits(component, AIU_CLK_CTRL,
 				      AIU_CLK_CTRL_LRCLK_INVERT |
@@ -272,6 +286,7 @@ static int aiu_encoder_i2s_set_sysclk(struct snd_soc_dai *dai, int clk_id,
 				      unsigned int freq, int dir)
 {
 	struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
+	struct gx_iface *iface = &aiu->i2s.iface;
 	int ret;
 
 	if (WARN_ON(clk_id != 0))
@@ -280,11 +295,15 @@ static int aiu_encoder_i2s_set_sysclk(struct snd_soc_dai *dai, int clk_id,
 	if (dir == SND_SOC_CLOCK_IN)
 		return 0;
 
-	ret = clk_set_rate(aiu->i2s.clks[MCLK].clk, freq);
-	if (ret)
-		dev_err(dai->dev, "Failed to set sysclk to %uHz", freq);
+	ret = clk_set_rate(iface->mclk, freq);
+	if (ret) {
+		dev_err(dai->dev, "Failed to set sysclk to %uHz: %d", freq, ret);
+		return ret;
+	}
 
-	return ret;
+	iface->mclk_rate = freq;
+
+	return 0;
 }
 
 static const unsigned int hw_channels[] = {2, 8};
@@ -305,15 +324,54 @@ static int aiu_encoder_i2s_startup(struct snd_pcm_substream *substream,
 					 SNDRV_PCM_HW_PARAM_CHANNELS,
 					 &hw_channel_constraints);
 	if (ret) {
-		dev_err(dai->dev, "adding channels constraints failed\n");
+		dev_err(dai->dev, "adding channels constraints failed: %d\n", ret);
 		return ret;
 	}
 
-	ret = clk_bulk_prepare_enable(aiu->i2s.clk_num, aiu->i2s.clks);
-	if (ret)
-		dev_err(dai->dev, "failed to enable i2s clocks\n");
+	/*
+	 * Enable only clocks which are required for the interface internal
+	 * logic. MCLK is enabled/disabled from the formatter and the I2S
+	 * divider is enabled/disabled in "hw_params"/"hw_free", respectively.
+	 */
+	ret = clk_prepare_enable(aiu->i2s.clks[PCLK].clk);
+	if (ret) {
+		dev_err(dai->dev, "failed to enable PCLK: %d\n", ret);
+		return ret;
+	}
+	ret = clk_prepare_enable(aiu->i2s.clks[MIXER].clk);
+	if (ret) {
+		dev_err(dai->dev, "failed to enable MIXER: %d\n", ret);
+		clk_disable_unprepare(aiu->i2s.clks[PCLK].clk);
+		return ret;
+	}
+	ret = clk_prepare_enable(aiu->i2s.clks[AOCLK].clk);
+	if (ret) {
+		dev_err(dai->dev, "failed to enable AOCLK: %d\n", ret);
+		clk_disable_unprepare(aiu->i2s.clks[MIXER].clk);
+		clk_disable_unprepare(aiu->i2s.clks[PCLK].clk);
+		return ret;
+	}
 
-	return ret;
+	/*
+	 * We're always operating in split mode for the playback stream.
+	 *
+	 * This setting arguably belong to the 'aiu-formatter', but it's kept
+	 * here for backward compatibility reason. At reset the I2S encoder
+	 * operates in normal mode which would only support 8ch, but by default
+	 * only 2ch are enabled. If a playback stream is started without
+	 * changing to split mode, then the I2S encoder doesn't consume audio
+	 * samples and the playback fails.
+	 * Moving this to 'aiu-formatter' would cause the split mode to be set
+	 * only when the formatter is enabled, which doesn't happen at boot as
+	 * the default value for "HDMI CTRL SRC" is "DISABLED".
+	 */
+	ret = snd_soc_component_update_bits(dai->component, AIU_I2S_SOURCE_DESC,
+					    AIU_I2S_SOURCE_DESC_MODE_SPLIT,
+					    AIU_I2S_SOURCE_DESC_MODE_SPLIT);
+	if (ret < 0)
+		dev_err(dai->dev, "failed to update AIU_I2S_SOURCE_DESC: %d", ret);
+
+	return 0;
 }
 
 static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream,
@@ -321,14 +379,89 @@ static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream,
 {
 	struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
 
-	clk_bulk_disable_unprepare(aiu->i2s.clk_num, aiu->i2s.clks);
+	clk_disable_unprepare(aiu->i2s.clks[AOCLK].clk);
+	clk_disable_unprepare(aiu->i2s.clks[MIXER].clk);
+	clk_disable_unprepare(aiu->i2s.clks[PCLK].clk);
+}
+
+static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream,
+				   int cmd,
+				   struct snd_soc_dai *dai)
+{
+	struct gx_stream *ts = snd_soc_dai_get_dma_data(dai, substream);
+	int ret;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		ret = gx_stream_start(ts);
+		break;
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+	case SNDRV_PCM_TRIGGER_STOP:
+		gx_stream_stop(ts);
+		ret = 0;
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int aiu_encoder_i2s_remove_dai(struct snd_soc_dai *dai)
+{
+	int stream;
+
+	for_each_pcm_streams(stream) {
+		struct gx_stream *ts;
+
+		ts = snd_soc_dai_dma_data_get(dai, stream);
+		if (ts)
+			gx_stream_free(ts);
+
+		snd_soc_dai_dma_data_set(dai, stream, NULL);
+	}
+
+	return 0;
+}
+
+static int aiu_encoder_i2s_probe_dai(struct snd_soc_dai *dai)
+{
+	struct aiu *aiu = snd_soc_dai_get_drvdata(dai);
+	struct gx_iface *iface = &aiu->i2s.iface;
+	int stream;
+
+	for_each_pcm_streams(stream) {
+		struct gx_stream *ts;
+
+		if (!snd_soc_dai_get_widget(dai, stream))
+			continue;
+
+		ts = gx_stream_alloc(iface);
+		if (!ts) {
+			aiu_encoder_i2s_remove_dai(dai);
+			return -ENOMEM;
+		}
+		snd_soc_dai_dma_data_set(dai, stream, ts);
+	}
+
+	iface->mclk = aiu->i2s.clks[MCLK].clk;
+	iface->mclk_rate = clk_get_rate(iface->mclk);
+
+	return 0;
 }
 
 const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = {
+	.probe		= aiu_encoder_i2s_probe_dai,
+	.remove		= aiu_encoder_i2s_remove_dai,
 	.hw_params	= aiu_encoder_i2s_hw_params,
+	.prepare	= aiu_encoder_i2s_prepare,
 	.hw_free	= aiu_encoder_i2s_hw_free,
 	.set_fmt	= aiu_encoder_i2s_set_fmt,
 	.set_sysclk	= aiu_encoder_i2s_set_sysclk,
 	.startup	= aiu_encoder_i2s_startup,
 	.shutdown	= aiu_encoder_i2s_shutdown,
+	.trigger	= aiu_encoder_i2s_trigger,
 };
diff --git a/sound/soc/meson/aiu-formatter-i2s.c b/sound/soc/meson/aiu-formatter-i2s.c
new file mode 100644
index 000000000000..b4604734fe88
--- /dev/null
+++ b/sound/soc/meson/aiu-formatter-i2s.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (c) 2026 BayLibre, SAS.
+// Author: Valerio Setti <vsetti@baylibre.com>
+
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/soc-dai.h>
+
+#include "aiu.h"
+#include "gx-formatter.h"
+
+#define AIU_I2S_SOURCE_DESC_MODE_8CH	BIT(0)
+#define AIU_I2S_SOURCE_DESC_MODE_24BIT	BIT(5)
+#define AIU_I2S_SOURCE_DESC_MODE_32BIT	BIT(9)
+#define AIU_RST_SOFT_I2S_FAST		BIT(0)
+
+#define AIU_I2S_DAC_CFG_MSB_FIRST	BIT(2)
+
+static struct snd_soc_dai *
+aiu_formatter_i2s_get_be(struct snd_soc_dapm_widget *w)
+{
+	struct snd_soc_dapm_path *p;
+	struct snd_soc_dai *be;
+
+	snd_soc_dapm_widget_for_each_sink_path(w, p) {
+		if (!p->connect)
+			continue;
+
+		if (p->sink->id == snd_soc_dapm_dai_in)
+			return (struct snd_soc_dai *)p->sink->priv;
+
+		be = aiu_formatter_i2s_get_be(p->sink);
+		if (be)
+			return be;
+	}
+
+	return NULL;
+}
+
+static struct gx_stream *
+aiu_formatter_i2s_get_stream(struct snd_soc_dapm_widget *w)
+{
+	struct snd_soc_dai *be = aiu_formatter_i2s_get_be(w);
+
+	if (!be)
+		return NULL;
+
+	return snd_soc_dai_dma_data_get_playback(be);
+}
+
+static int aiu_formatter_i2s_prepare(struct regmap *map,
+				 const struct gx_formatter_hw *quirks,
+				 struct gx_stream *ts)
+{
+	/* Always operate in split (classic interleaved) mode */
+	unsigned int desc = 0;
+	unsigned int tmp;
+
+	/* Reset required to update the pipeline */
+	regmap_write(map, AIU_RST_SOFT, AIU_RST_SOFT_I2S_FAST);
+	regmap_read(map, AIU_I2S_SYNC, &tmp);
+
+	switch (ts->physical_width) {
+	case 16: /* Nothing to do */
+		break;
+
+	case 32:
+		desc |= (AIU_I2S_SOURCE_DESC_MODE_24BIT |
+			 AIU_I2S_SOURCE_DESC_MODE_32BIT);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	switch (ts->channels) {
+	case 2: /* Nothing to do */
+		break;
+	case 8:
+		desc |= AIU_I2S_SOURCE_DESC_MODE_8CH;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	regmap_update_bits(map, AIU_I2S_SOURCE_DESC,
+				AIU_I2S_SOURCE_DESC_MODE_8CH |
+				AIU_I2S_SOURCE_DESC_MODE_24BIT |
+				AIU_I2S_SOURCE_DESC_MODE_32BIT,
+				desc);
+
+	/* Send data MSB first */
+	regmap_update_bits(map, AIU_I2S_DAC_CFG,
+				AIU_I2S_DAC_CFG_MSB_FIRST,
+				AIU_I2S_DAC_CFG_MSB_FIRST);
+
+	return 0;
+}
+
+const struct gx_formatter_ops aiu_formatter_i2s_ops = {
+	.get_stream	= aiu_formatter_i2s_get_stream,
+	.prepare	= aiu_formatter_i2s_prepare,
+};
diff --git a/sound/soc/meson/aiu.c b/sound/soc/meson/aiu.c
index f2890111c1d2..64ace4d25d92 100644
--- a/sound/soc/meson/aiu.c
+++ b/sound/soc/meson/aiu.c
@@ -29,13 +29,22 @@ static SOC_ENUM_SINGLE_DECL(aiu_spdif_encode_sel_enum, AIU_I2S_MISC,
 static const struct snd_kcontrol_new aiu_spdif_encode_mux =
 	SOC_DAPM_ENUM("SPDIF Buffer Src", aiu_spdif_encode_sel_enum);
 
-static const struct snd_soc_dapm_widget aiu_cpu_dapm_widgets[] = {
-	SND_SOC_DAPM_MUX("SPDIF SRC SEL", SND_SOC_NOPM, 0, 0,
-			 &aiu_spdif_encode_mux),
+#define AIU_WIDGET_SPDIF_SRC_SEL	0
+#define AIU_WIDGET_I2S_FORMATTER	1
+
+static struct snd_soc_dapm_widget aiu_cpu_dapm_widgets[] = {
+	[AIU_WIDGET_SPDIF_SRC_SEL] =
+		SND_SOC_DAPM_MUX("SPDIF SRC SEL", SND_SOC_NOPM, 0, 0,
+				 &aiu_spdif_encode_mux),
+	[AIU_WIDGET_I2S_FORMATTER] =
+		SND_SOC_DAPM_PGA_E("I2S Formatter", SND_SOC_NOPM, 0, 0, NULL, 0,
+				   gx_formatter_event,
+				   (SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_PRE_PMD)),
 };
 
 static const struct snd_soc_dapm_route aiu_cpu_dapm_routes[] = {
-	{ "I2S Encoder Playback", NULL, "I2S FIFO Playback" },
+	{ "I2S Formatter", NULL, "I2S FIFO Playback" },
+	{ "I2S Encoder Playback", NULL, "I2S Formatter" },
 	{ "SPDIF SRC SEL", "SPDIF", "SPDIF FIFO Playback" },
 	{ "SPDIF SRC SEL", "I2S", "I2S FIFO Playback" },
 	{ "SPDIF Encoder Playback", NULL, "SPDIF SRC SEL" },
@@ -172,6 +181,11 @@ static const struct regmap_config aiu_regmap_cfg = {
 	.max_register	= 0x2ac,
 };
 
+const struct gx_formatter_driver aiu_formatter_i2s_drv = {
+	.regmap_cfg	= &aiu_regmap_cfg,
+	.ops		= &aiu_formatter_i2s_ops,
+};
+
 static int aiu_clk_bulk_get(struct device *dev,
 			    const char * const *ids,
 			    unsigned int num,
@@ -282,6 +296,14 @@ static int aiu_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	/* Allocate the aiu-formatter into its widget */
+	ret = gx_formatter_create(dev, &aiu_cpu_dapm_widgets[AIU_WIDGET_I2S_FORMATTER],
+				  &aiu_formatter_i2s_drv, map);
+	if (ret) {
+		dev_err(dev, "Failed to allocate aiu formatter\n");
+		goto err;
+	}
+
 	/* Register the cpu component of the aiu */
 	ret = snd_soc_register_component(dev, &aiu_cpu_component,
 					 aiu_cpu_dai_drv,
@@ -310,12 +332,14 @@ static int aiu_probe(struct platform_device *pdev)
 
 	return 0;
 err:
+	gx_formatter_free(&aiu_cpu_dapm_widgets[AIU_WIDGET_I2S_FORMATTER]);
 	snd_soc_unregister_component(dev);
 	return ret;
 }
 
 static void aiu_remove(struct platform_device *pdev)
 {
+	gx_formatter_free(&aiu_cpu_dapm_widgets[AIU_WIDGET_I2S_FORMATTER]);
 	snd_soc_unregister_component(&pdev->dev);
 }
 
diff --git a/sound/soc/meson/aiu.h b/sound/soc/meson/aiu.h
index 0f94c8bf6081..7d0b98c1f351 100644
--- a/sound/soc/meson/aiu.h
+++ b/sound/soc/meson/aiu.h
@@ -7,6 +7,8 @@
 #ifndef _MESON_AIU_H
 #define _MESON_AIU_H
 
+#include "gx-formatter.h"
+
 struct clk;
 struct clk_bulk_data;
 struct device;
@@ -25,6 +27,7 @@ struct aiu_interface {
 	struct clk_bulk_data *clks;
 	unsigned int clk_num;
 	int irq;
+	struct gx_iface iface;
 };
 
 struct aiu_platform_data {
@@ -58,6 +61,7 @@ extern const struct snd_soc_dai_ops aiu_fifo_i2s_dai_ops;
 extern const struct snd_soc_dai_ops aiu_fifo_spdif_dai_ops;
 extern const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops;
 extern const struct snd_soc_dai_ops aiu_encoder_spdif_dai_ops;
+extern const struct gx_formatter_ops aiu_formatter_i2s_ops;
 
 #define AIU_IEC958_BPF			0x000
 #define AIU_958_MISC			0x010
diff --git a/sound/soc/meson/gx-formatter.c b/sound/soc/meson/gx-formatter.c
new file mode 100644
index 000000000000..311e63affb23
--- /dev/null
+++ b/sound/soc/meson/gx-formatter.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+//
+// Copyright (c) 2026 BayLibre, SAS.
+// Author: Valerio Setti <vsetti@baylibre.com>
+
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/regmap.h>
+#include <sound/soc.h>
+
+#include "gx-formatter.h"
+
+struct gx_formatter {
+	struct list_head list;
+	struct gx_stream *stream;
+	const struct gx_formatter_driver *drv;
+	bool enabled;
+	struct regmap *map;
+};
+
+static int gx_formatter_enable(struct gx_formatter *formatter)
+{
+	int ret;
+
+	/* Do nothing if the formatter is already enabled */
+	if (formatter->enabled)
+		return 0;
+
+	/* Setup the stream parameter in the formatter */
+	if (formatter->drv->ops->prepare) {
+		ret = formatter->drv->ops->prepare(formatter->map,
+					   formatter->drv->quirks,
+					   formatter->stream);
+		if (ret)
+			return ret;
+	}
+
+	/* Finally, actually enable the formatter */
+	if (formatter->drv->ops->enable)
+		formatter->drv->ops->enable(formatter->map);
+
+	formatter->enabled = true;
+
+	return 0;
+}
+
+static void gx_formatter_disable(struct gx_formatter *formatter)
+{
+	/* Do nothing if the formatter is already disabled */
+	if (!formatter->enabled)
+		return;
+
+	if (formatter->drv->ops->disable)
+		formatter->drv->ops->disable(formatter->map);
+
+	formatter->enabled = false;
+}
+
+static int gx_formatter_attach(struct gx_formatter *formatter)
+{
+	struct gx_stream *ts = formatter->stream;
+	int ret = 0;
+
+	mutex_lock(&ts->lock);
+
+	/* Catch up if the stream is already running when we attach */
+	if (ts->ready) {
+		ret = gx_formatter_enable(formatter);
+		if (ret) {
+			pr_err("failed to enable formatter\n");
+			goto out;
+		}
+	}
+
+	list_add_tail(&formatter->list, &ts->formatter_list);
+out:
+	mutex_unlock(&ts->lock);
+	return ret;
+}
+
+static void gx_formatter_detach(struct gx_formatter *formatter)
+{
+	struct gx_stream *ts = formatter->stream;
+
+	if (!ts)
+		return;
+
+	mutex_lock(&ts->lock);
+	list_del(&formatter->list);
+	mutex_unlock(&ts->lock);
+
+	gx_formatter_disable(formatter);
+}
+
+static int gx_formatter_power_up(struct gx_formatter *formatter,
+				      struct snd_soc_dapm_widget *w)
+{
+	struct gx_stream *ts = formatter->drv->ops->get_stream(w);
+	int ret;
+
+	/*
+	 * If we don't get a stream at this stage, it would mean that the
+	 * widget is powering up but is not attached to any backend DAI.
+	 * It should not happen, ever !
+	 */
+	if (WARN_ON(!ts))
+		return -ENODEV;
+
+	formatter->stream = ts;
+	INIT_LIST_HEAD(&formatter->list);
+	ret = gx_formatter_attach(formatter);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static void gx_formatter_power_down(struct gx_formatter *formatter)
+{
+	gx_formatter_detach(formatter);
+	formatter->stream = NULL;
+}
+
+int gx_formatter_event(struct snd_soc_dapm_widget *w,
+		       struct snd_kcontrol *control,
+		       int event)
+{
+	struct snd_soc_component *c;
+	struct gx_formatter *formatter;
+	int ret = 0;
+
+	c = snd_soc_dapm_to_component(w->dapm);
+
+	if (w->priv)
+		formatter = w->priv;
+	else
+		formatter = snd_soc_component_get_drvdata(c);
+
+	switch (event) {
+	case SND_SOC_DAPM_PRE_PMU:
+		ret = gx_formatter_power_up(formatter, w);
+		break;
+
+	case SND_SOC_DAPM_PRE_PMD:
+		gx_formatter_power_down(formatter);
+		break;
+
+	default:
+		dev_err(c->dev, "Unexpected event %d\n", event);
+		return -EINVAL;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(gx_formatter_event);
+
+int gx_formatter_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct gx_formatter_driver *drv;
+	struct gx_formatter *formatter;
+	void __iomem *regs;
+
+	drv = of_device_get_match_data(dev);
+	if (!drv) {
+		dev_err(dev, "failed to match device\n");
+		return -ENODEV;
+	}
+
+	formatter = devm_kzalloc(dev, sizeof(*formatter), GFP_KERNEL);
+	if (!formatter)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, formatter);
+	formatter->drv = drv;
+
+	regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	formatter->map = devm_regmap_init_mmio(dev, regs, drv->regmap_cfg);
+	if (IS_ERR(formatter->map)) {
+		dev_err(dev, "failed to init regmap: %ld\n",
+			PTR_ERR(formatter->map));
+		return PTR_ERR(formatter->map);
+	}
+
+	return devm_snd_soc_register_component(dev, drv->component_drv,
+					       NULL, 0);
+}
+EXPORT_SYMBOL_GPL(gx_formatter_probe);
+
+int gx_formatter_create(struct device *dev,
+			struct snd_soc_dapm_widget *w,
+			const struct gx_formatter_driver *drv,
+			struct regmap *regmap)
+{
+	struct gx_formatter *formatter;
+
+	formatter = devm_kzalloc(dev, sizeof(*formatter), GFP_KERNEL);
+	if (!formatter)
+		return -ENOMEM;
+
+	formatter->drv = drv;
+	formatter->map = regmap;
+
+	w->priv = formatter;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(gx_formatter_create);
+
+int gx_stream_start(struct gx_stream *ts)
+{
+	struct gx_formatter *formatter;
+	int ret = 0;
+
+	mutex_lock(&ts->lock);
+
+	/* Start all the formatters attached to the stream */
+	list_for_each_entry(formatter, &ts->formatter_list, list) {
+		ret = gx_formatter_enable(formatter);
+		if (ret) {
+			pr_err("failed to enable formatter\n");
+			goto out;
+		}
+	}
+
+	ts->ready = true;
+
+out:
+	mutex_unlock(&ts->lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(gx_stream_start);
+
+void gx_stream_stop(struct gx_stream *ts)
+{
+	struct gx_formatter *formatter;
+
+	mutex_lock(&ts->lock);
+	ts->ready = false;
+
+	/* Stop all the formatters attached to the stream */
+	list_for_each_entry(formatter, &ts->formatter_list, list) {
+		gx_formatter_disable(formatter);
+	}
+
+	mutex_unlock(&ts->lock);
+}
+EXPORT_SYMBOL_GPL(gx_stream_stop);
+
+struct gx_stream *gx_stream_alloc(struct gx_iface *iface)
+{
+	struct gx_stream *ts;
+
+	ts = kzalloc(sizeof(*ts), GFP_KERNEL);
+	if (ts) {
+		INIT_LIST_HEAD(&ts->formatter_list);
+		mutex_init(&ts->lock);
+		ts->iface = iface;
+	}
+
+	return ts;
+}
+EXPORT_SYMBOL_GPL(gx_stream_alloc);
+
+void gx_stream_free(struct gx_stream *ts)
+{
+	/*
+	 * If the list is not empty, it would mean that one of the formatter
+	 * widget is still powered and attached to the interface while we
+	 * are removing the TDM DAI. It should not be possible
+	 */
+	WARN_ON(!list_empty(&ts->formatter_list));
+	mutex_destroy(&ts->lock);
+	kfree(ts);
+}
+EXPORT_SYMBOL_GPL(gx_stream_free);
+
+MODULE_DESCRIPTION("Amlogic GX formatter driver");
+MODULE_AUTHOR("Valerio Setti <vsetti@baylibre.com>");
+MODULE_LICENSE("GPL");
diff --git a/sound/soc/meson/gx-formatter.h b/sound/soc/meson/gx-formatter.h
new file mode 100644
index 000000000000..b90b1814d79b
--- /dev/null
+++ b/sound/soc/meson/gx-formatter.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
+/*
+ * Copyright (c) 2026 Baylibre SAS.
+ * Author: Valerio Setti <vsetti@baylibre.com>
+ */
+
+#ifndef _MESON_GX_FORMATTER_H
+#define _MESON_GX_FORMATTER_H
+
+#include "gx-interface.h"
+
+struct platform_device;
+struct regmap;
+struct snd_soc_dapm_widget;
+struct snd_kcontrol;
+
+struct gx_formatter_hw {
+	unsigned int skew_offset;
+};
+
+struct gx_formatter_ops {
+	struct gx_stream *(*get_stream)(struct snd_soc_dapm_widget *w);
+	void (*enable)(struct regmap *map);
+	void (*disable)(struct regmap *map);
+	int (*prepare)(struct regmap *map,
+		       const struct gx_formatter_hw *quirks,
+		       struct gx_stream *ts);
+};
+
+struct gx_formatter_driver {
+	const struct snd_soc_component_driver *component_drv;
+	const struct regmap_config *regmap_cfg;
+	const struct gx_formatter_ops *ops;
+	const struct gx_formatter_hw *quirks;
+};
+
+int gx_formatter_event(struct snd_soc_dapm_widget *w,
+		       struct snd_kcontrol *control,
+		       int event);
+int gx_formatter_probe(struct platform_device *pdev);
+
+int gx_formatter_create(struct device *dev,
+			struct snd_soc_dapm_widget *w,
+			const struct gx_formatter_driver *drv,
+			struct regmap *regmap);
+
+/*
+ * Formatter data is already freed when the associated device is removed,
+ * so we just need to remove the pointer from the widget.
+ */
+static inline void gx_formatter_free(struct snd_soc_dapm_widget *w)
+{
+	w->priv = NULL;
+}
+
+#endif /* _MESON_GX_FORMATTER_H */
diff --git a/sound/soc/meson/gx-interface.h b/sound/soc/meson/gx-interface.h
new file mode 100644
index 000000000000..65c46dcce32a
--- /dev/null
+++ b/sound/soc/meson/gx-interface.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
+/*
+ * Copyright (c) 2026 Baylibre SAS.
+ * Author: Valerio Setti <vsetti@baylibre.com>
+ */
+
+#ifndef _MESON_GX_INTERFACE_H
+#define _MESON_GX_INTERFACE_H
+
+#include <linux/clk.h>
+#include <linux/regmap.h>
+#include <sound/pcm.h>
+#include <sound/soc.h>
+#include <sound/soc-dai.h>
+
+struct gx_iface {
+	struct clk *mclk;
+	unsigned long mclk_rate;
+
+	/* format is common to all the DAIs of the iface */
+	unsigned int fmt;
+
+	/* For component wide symmetry */
+	int rate;
+
+	/* Only for GX platform */
+	int bs_quirk;
+};
+
+struct gx_stream {
+	struct gx_iface *iface;
+	struct list_head formatter_list;
+	struct mutex lock;
+	unsigned int channels;
+	unsigned int width;
+	unsigned int physical_width;
+	bool ready;
+
+	/* For continuous clock tracking */
+	bool clk_enabled;
+};
+
+struct gx_stream *gx_stream_alloc(struct gx_iface *iface);
+void gx_stream_free(struct gx_stream *ts);
+int gx_stream_start(struct gx_stream *ts);
+void gx_stream_stop(struct gx_stream *ts);
+
+#endif /* _MESON_GX_INTERFACE_H */