ASoC: cs40l50: Support I2S streaming to CS40L50

Introduce support for Cirrus Logic Device CS40L50: a
haptic driver with waveform memory, integrated DSP,
and closed-loop algorithms.

The ASoC driver enables I2S streaming to the device.

Reviewed-by: David Rhodes <[e-mail]>
Signed-off-by: James Ogletree <[e-mail]>
Reviewed-by: Jeff LaBundy <[e-mail]>
Reviewed-by: Ricardo Rivera-Matos <[e-mail]>
Reviewed-by: Mark Brown <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Lee Jones <[e-mail]>

MAINTAINERS

···
 F:	drivers/input/misc/cs40l*
 F:	drivers/mfd/cs40l*
 F:	include/linux/mfd/cs40l*
+F:	sound/soc/codecs/cs40l*
 
 CIRRUS LOGIC DSP FIRMWARE DRIVER
 M:	Simon Trimmer <[e-mail]>

sound/soc/codecs/Kconfig

···
 	imply SND_SOC_CS35L56_I2C
 	imply SND_SOC_CS35L56_SPI
 	imply SND_SOC_CS35L56_SDW
+	imply SND_SOC_CS40L50
 	imply SND_SOC_CS42L42
 	imply SND_SOC_CS42L42_SDW
 	imply SND_SOC_CS42L43
···
 	select SND_SOC_CS35L56_SHARED
 	help
 	  Enable support for Cirrus Logic CS35L56 boosted amplifier with SoundWire control
+
+config SND_SOC_CS40L50
+	tristate "Cirrus Logic CS40L50 CODEC"
+	depends on MFD_CS40L50_CORE
+	help
+	  This option enables support for I2S streaming to Cirrus Logic CS40L50.
+
+	  CS40L50 is a haptic driver with waveform memory, an integrated
+	  DSP, and closed-loop algorithms. If built as a module, it will be
+	  called snd-soc-cs40l50.
 
 config SND_SOC_CS42L42_CORE
 	tristate

sound/soc/codecs/Makefile

···
 snd-soc-cs35l56-i2c-y := cs35l56-i2c.o
 snd-soc-cs35l56-spi-y := cs35l56-spi.o
 snd-soc-cs35l56-sdw-y := cs35l56-sdw.o
+snd-soc-cs40l50-objs := cs40l50-codec.o
 snd-soc-cs42l42-y := cs42l42.o
 snd-soc-cs42l42-i2c-y := cs42l42-i2c.o
 snd-soc-cs42l42-sdw-y := cs42l42-sdw.o
···
 obj-$(CONFIG_SND_SOC_CS35L56_I2C)	+= snd-soc-cs35l56-i2c.o
 obj-$(CONFIG_SND_SOC_CS35L56_SPI)	+= snd-soc-cs35l56-spi.o
 obj-$(CONFIG_SND_SOC_CS35L56_SDW)	+= snd-soc-cs35l56-sdw.o
+obj-$(CONFIG_SND_SOC_CS40L50)		+= snd-soc-cs40l50.o
 obj-$(CONFIG_SND_SOC_CS42L42_CORE)	+= snd-soc-cs42l42.o
 obj-$(CONFIG_SND_SOC_CS42L42)	+= snd-soc-cs42l42-i2c.o
 obj-$(CONFIG_SND_SOC_CS42L42_SDW)	+= snd-soc-cs42l42-sdw.o

sound/soc/codecs/cs40l50-codec.c

···
+// SPDX-License-Identifier: GPL-2.0
+//
+// CS40L50 Advanced Haptic Driver with waveform memory,
+// integrated DSP, and closed-loop algorithms
+//
+// Copyright 2024 Cirrus Logic, Inc.
+//
+// Author: James Ogletree <[e-mail]>
+
+#include <linux/bitfield.h>
+#include <linux/mfd/cs40l50.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#define CS40L50_REFCLK_INPUT		0x2C04
+#define CS40L50_ASP_CONTROL2		0x4808
+#define CS40L50_ASP_DATA_CONTROL5	0x4840
+
+/* PLL Config */
+#define CS40L50_PLL_REFCLK_BCLK		0x0
+#define CS40L50_PLL_REFCLK_MCLK		0x5
+#define CS40L50_PLL_REEFCLK_MCLK_CFG	0x00
+#define CS40L50_PLL_REFCLK_LOOP_MASK	BIT(11)
+#define CS40L50_PLL_REFCLK_OPEN_LOOP	1
+#define CS40L50_PLL_REFCLK_CLOSED_LOOP	0
+#define CS40L50_PLL_REFCLK_LOOP_SHIFT	11
+#define CS40L50_PLL_REFCLK_FREQ_MASK	GENMASK(10, 5)
+#define CS40L50_PLL_REFCLK_FREQ_SHIFT	5
+#define CS40L50_PLL_REFCLK_SEL_MASK	GENMASK(2, 0)
+#define CS40L50_BCLK_RATIO_DEFAULT	32
+
+/* ASP Config */
+#define CS40L50_ASP_RX_WIDTH_SHIFT	24
+#define CS40L50_ASP_RX_WIDTH_MASK	GENMASK(31, 24)
+#define CS40L50_ASP_RX_WL_MASK		GENMASK(5, 0)
+#define CS40L50_ASP_FSYNC_INV_MASK	BIT(2)
+#define CS40L50_ASP_BCLK_INV_MASK	BIT(6)
+#define CS40L50_ASP_FMT_MASK		GENMASK(10, 8)
+#define CS40L50_ASP_FMT_I2S		0x2
+
+struct cs40l50_pll_config {
+	unsigned int freq;
+	unsigned int cfg;
+};
+
+struct cs40l50_codec {
+	struct device *dev;
+	struct regmap *regmap;
+	unsigned int daifmt;
+	unsigned int bclk_ratio;
+	unsigned int rate;
+};
+
+static const struct cs40l50_pll_config cs40l50_pll_cfg[] = {
+	{ 32768, 0x00 },
+	{ 1536000, 0x1B },
+	{ 3072000, 0x21 },
+	{ 6144000, 0x28 },
+	{ 9600000, 0x30 },
+	{ 12288000, 0x33 },
+};
+
+static int cs40l50_get_clk_config(const unsigned int freq, unsigned int *cfg)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(cs40l50_pll_cfg); i++) {
+		if (cs40l50_pll_cfg[i].freq == freq) {
+			*cfg = cs40l50_pll_cfg[i].cfg;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int cs40l50_swap_ext_clk(struct cs40l50_codec *codec, const unsigned int clk_src)
+{
+	unsigned int cfg;
+	int ret;
+
+	switch (clk_src) {
+	case CS40L50_PLL_REFCLK_BCLK:
+		ret = cs40l50_get_clk_config(codec->bclk_ratio * codec->rate, &cfg);
+		if (ret)
+			return ret;
+		break;
+	case CS40L50_PLL_REFCLK_MCLK:
+		cfg = CS40L50_PLL_REEFCLK_MCLK_CFG;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = regmap_update_bits(codec->regmap, CS40L50_REFCLK_INPUT,
+				 CS40L50_PLL_REFCLK_LOOP_MASK,
+				 CS40L50_PLL_REFCLK_OPEN_LOOP <<
+				 CS40L50_PLL_REFCLK_LOOP_SHIFT);
+	if (ret)
+		return ret;
+
+	ret = regmap_update_bits(codec->regmap, CS40L50_REFCLK_INPUT,
+				 CS40L50_PLL_REFCLK_FREQ_MASK |
+				 CS40L50_PLL_REFCLK_SEL_MASK,
+				 (cfg << CS40L50_PLL_REFCLK_FREQ_SHIFT) | clk_src);
+	if (ret)
+		return ret;
+
+	return regmap_update_bits(codec->regmap, CS40L50_REFCLK_INPUT,
+				  CS40L50_PLL_REFCLK_LOOP_MASK,
+				  CS40L50_PLL_REFCLK_CLOSED_LOOP <<
+				  CS40L50_PLL_REFCLK_LOOP_SHIFT);
+}
+
+static int cs40l50_clk_en(struct snd_soc_dapm_widget *w,
+			  struct snd_kcontrol *kcontrol,
+			  int event)
+{
+	struct snd_soc_component *comp = snd_soc_dapm_to_component(w->dapm);
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(comp);
+	int ret;
+
+	switch (event) {
+	case SND_SOC_DAPM_POST_PMU:
+		ret = cs40l50_dsp_write(codec->dev, codec->regmap, CS40L50_STOP_PLAYBACK);
+		if (ret)
+			return ret;
+
+		ret = cs40l50_dsp_write(codec->dev, codec->regmap, CS40L50_START_I2S);
+		if (ret)
+			return ret;
+
+		ret = cs40l50_swap_ext_clk(codec, CS40L50_PLL_REFCLK_BCLK);
+		if (ret)
+			return ret;
+		break;
+	case SND_SOC_DAPM_PRE_PMD:
+		ret = cs40l50_swap_ext_clk(codec, CS40L50_PLL_REFCLK_MCLK);
+		if (ret)
+			return ret;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static const struct snd_soc_dapm_widget cs40l50_dapm_widgets[] = {
+	SND_SOC_DAPM_SUPPLY_S("ASP PLL", 0, SND_SOC_NOPM, 0, 0, cs40l50_clk_en,
+			      SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
+	SND_SOC_DAPM_AIF_IN("ASPRX1", NULL, 0, SND_SOC_NOPM, 0, 0),
+	SND_SOC_DAPM_AIF_IN("ASPRX2", NULL, 0, SND_SOC_NOPM, 0, 0),
+	SND_SOC_DAPM_OUTPUT("OUT"),
+};
+
+static const struct snd_soc_dapm_route cs40l50_dapm_routes[] = {
+	{ "ASP Playback", NULL, "ASP PLL" },
+	{ "ASPRX1", NULL, "ASP Playback" },
+	{ "ASPRX2", NULL, "ASP Playback" },
+
+	{ "OUT", NULL, "ASPRX1" },
+	{ "OUT", NULL, "ASPRX2" },
+};
+
+static int cs40l50_set_dai_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
+{
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(codec_dai->component);
+
+	if ((fmt & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBC_CFC)
+		return -EINVAL;
+
+	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+	case SND_SOC_DAIFMT_NB_NF:
+		codec->daifmt = 0;
+		break;
+	case SND_SOC_DAIFMT_NB_IF:
+		codec->daifmt = CS40L50_ASP_FSYNC_INV_MASK;
+		break;
+	case SND_SOC_DAIFMT_IB_NF:
+		codec->daifmt = CS40L50_ASP_BCLK_INV_MASK;
+		break;
+	case SND_SOC_DAIFMT_IB_IF:
+		codec->daifmt = CS40L50_ASP_FSYNC_INV_MASK | CS40L50_ASP_BCLK_INV_MASK;
+		break;
+	default:
+		dev_err(codec->dev, "Invalid clock invert\n");
+		return -EINVAL;
+	}
+
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_I2S:
+		codec->daifmt |= FIELD_PREP(CS40L50_ASP_FMT_MASK, CS40L50_ASP_FMT_I2S);
+		break;
+	default:
+		dev_err(codec->dev, "Unsupported DAI format\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int cs40l50_hw_params(struct snd_pcm_substream *substream,
+			     struct snd_pcm_hw_params *params,
+			     struct snd_soc_dai *dai)
+{
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(dai->component);
+	unsigned int asp_rx_wl = params_width(params);
+	int ret;
+
+	codec->rate = params_rate(params);
+
+	ret = regmap_update_bits(codec->regmap, CS40L50_ASP_DATA_CONTROL5,
+				 CS40L50_ASP_RX_WL_MASK, asp_rx_wl);
+	if (ret)
+		return ret;
+
+	codec->daifmt |= (asp_rx_wl << CS40L50_ASP_RX_WIDTH_SHIFT);
+
+	return regmap_update_bits(codec->regmap, CS40L50_ASP_CONTROL2,
+				  CS40L50_ASP_FSYNC_INV_MASK |
+				  CS40L50_ASP_BCLK_INV_MASK |
+				  CS40L50_ASP_FMT_MASK |
+				  CS40L50_ASP_RX_WIDTH_MASK, codec->daifmt);
+}
+
+static int cs40l50_set_dai_bclk_ratio(struct snd_soc_dai *dai, unsigned int ratio)
+{
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(dai->component);
+
+	codec->bclk_ratio = ratio;
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops cs40l50_dai_ops = {
+	.set_fmt = cs40l50_set_dai_fmt,
+	.set_bclk_ratio = cs40l50_set_dai_bclk_ratio,
+	.hw_params = cs40l50_hw_params,
+};
+
+static struct snd_soc_dai_driver cs40l50_dai[] = {
+	{
+		.name = "cs40l50-pcm",
+		.id = 0,
+		.playback = {
+			.stream_name = "ASP Playback",
+			.channels_min = 1,
+			.channels_max = 2,
+			.rates = SNDRV_PCM_RATE_48000,
+			.formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE,
+		},
+		.ops = &cs40l50_dai_ops,
+	},
+};
+
+static int cs40l50_codec_probe(struct snd_soc_component *component)
+{
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(component);
+
+	codec->bclk_ratio = CS40L50_BCLK_RATIO_DEFAULT;
+
+	return 0;
+}
+
+static const struct snd_soc_component_driver soc_codec_dev_cs40l50 = {
+	.probe = cs40l50_codec_probe,
+	.dapm_widgets = cs40l50_dapm_widgets,
+	.num_dapm_widgets = ARRAY_SIZE(cs40l50_dapm_widgets),
+	.dapm_routes = cs40l50_dapm_routes,
+	.num_dapm_routes = ARRAY_SIZE(cs40l50_dapm_routes),
+};
+
+static int cs40l50_codec_driver_probe(struct platform_device *pdev)
+{
+	struct cs40l50 *cs40l50 = dev_get_drvdata(pdev->dev.parent);
+	struct cs40l50_codec *codec;
+
+	codec = devm_kzalloc(&pdev->dev, sizeof(*codec), GFP_KERNEL);
+	if (!codec)
+		return -ENOMEM;
+
+	codec->regmap = cs40l50->regmap;
+	codec->dev = &pdev->dev;
+
+	return devm_snd_soc_register_component(&pdev->dev, &soc_codec_dev_cs40l50,
+					       cs40l50_dai, ARRAY_SIZE(cs40l50_dai));
+}
+
+static const struct platform_device_id cs40l50_id[] = {
+	{ "cs40l50-codec", },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, cs40l50_id);
+
+static struct platform_driver cs40l50_codec_driver = {
+	.probe = cs40l50_codec_driver_probe,
+	.id_table = cs40l50_id,
+	.driver = {
+		.name = "cs40l50-codec",
+	},
+};
+module_platform_driver(cs40l50_codec_driver);
+
+MODULE_DESCRIPTION("ASoC CS40L50 driver");
+MODULE_AUTHOR("James Ogletree <[e-mail]>");
+MODULE_LICENSE("GPL");