[v2,2/2] ASoC: starfive: Add PDM controller support

diff --git a/MAINTAINERS b/MAINTAINERS
index c23fda1aa1f0..cf6e26ce16e9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21079,6 +21079,13 @@  F:	Documentation/devicetree/bindings/power/starfive*
 F:	drivers/pmdomain/starfive/
 F:	include/dt-bindings/power/starfive,jh7110-pmu.h
 
+STARFIVE JH8100 PDM DRIVER
+M:	Xingyu Wu <xingyu.wu@starfivetech.com>
+M:	Walker Chen <walker.chen@starfivetech.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/sound/starfive,jh8100-pdm.yaml
+F:	sound/soc/starfive/jh8100_pdm.c
+
 STARFIVE SOC DRIVERS
 M:	Conor Dooley <conor@kernel.org>
 S:	Maintained
diff --git a/sound/soc/starfive/Kconfig b/sound/soc/starfive/Kconfig
index 279ac5c1d309..f6b03ab0dd98 100644
--- a/sound/soc/starfive/Kconfig
+++ b/sound/soc/starfive/Kconfig
@@ -22,3 +22,10 @@  config SND_SOC_JH7110_TDM
 	select SND_SOC_GENERIC_DMAENGINE_PCM
 	help
 	  Say Y or M if you want to add support for StarFive TDM driver.
+
+config SND_SOC_JH8100_PDM
+	tristate "JH8100 PDM controller device driver"
+	depends on HAVE_CLK && SND_SOC_STARFIVE
+	select REGMAP_MMIO
+	help
+	  Say Y or M if you want to add support for StarFive PDM driver.
diff --git a/sound/soc/starfive/Makefile b/sound/soc/starfive/Makefile
index 9e958f70ef51..b672425830d9 100644
--- a/sound/soc/starfive/Makefile
+++ b/sound/soc/starfive/Makefile
@@ -1,3 +1,4 @@ 
 # StarFive Platform Support
 obj-$(CONFIG_SND_SOC_JH7110_PWMDAC) += jh7110_pwmdac.o
 obj-$(CONFIG_SND_SOC_JH7110_TDM) += jh7110_tdm.o
+obj-$(CONFIG_SND_SOC_JH8100_PDM) += jh8100_pdm.o
diff --git a/sound/soc/starfive/jh8100_pdm.c b/sound/soc/starfive/jh8100_pdm.c
new file mode 100644
index 000000000000..74b5f22622cc
--- /dev/null
+++ b/sound/soc/starfive/jh8100_pdm.c
@@ -0,0 +1,447 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PDM driver for the StarFive JH8100 SoC
+ *
+ * Copyright (C) 2024 StarFive Technology Co., Ltd.
+ */
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <sound/dmaengine_pcm.h>
+#include <sound/tlv.h>
+
+/* PDM RES: BLOCK 0 */
+#define JH8100_PDM_DMIC_CTRL0			0x00
+#define JH8100_PDM_DC_SCALE0			0x04
+/* BLOCK 1 */
+#define JH8100_PDM_DMIC_CTRL1			0x10
+#define JH8100_PDM_DC_SCALE1			0x14
+
+#define JH8100_PDM_BLOCKX_SHIFT			0x10
+#define JH8100_PDM_GET_CTRLX(x)			(JH8100_PDM_DMIC_CTRL0 + \
+						 (x) * JH8100_PDM_BLOCKX_SHIFT)
+#define JH8100_PDM_GET_SCALEX(x)		(JH8100_PDM_DC_SCALE0 + \
+						 (x) * JH8100_PDM_BLOCKX_SHIFT)
+
+/* PDM CTRL0/1 OFFSET */
+#define JH8100_PDM_DMIC_MSB_MASK		GENMASK(3, 1)
+#define JH8100_PDM_DMIC_VOL_MASK		GENMASK(21, 16)
+#define JH8100_PDM_VOL_DB_MUTE			GENMASK(21, 16)
+#define JH8100_PDM_VOL_DB_MAX			0
+
+#define JH8100_PDM_DMIC_RSWITCH_MASK		BIT(22)
+#define JH8100_PDM_DMIC_LSWITCH_MASK		BIT(23)
+#define JH8100_PDM_DMIC_I2S_SLAVE		BIT(24)
+#define JH8100_PDM_DMIC_HPF_EN			BIT(28)
+#define JH8100_PDM_DMIC_FASTMODE_MASK		BIT(29)
+#define JH8100_PDM_SW_RST_MASK			BIT(31)
+#define JH8100_PDM_SW_RST_RELEASE		BIT(31)
+
+/* PDM SCALE0/1 OFFSET */
+#define JH8100_DMIC_DCOFF_MASK			GENMASK(27, 8)
+#define JH8100_DMIC_DCOFF_DEF_VAL		0xc0005
+#define JH8100_DMIC_SCALE_MASK			GENMASK(5, 0)
+#define JH8100_DMIC_SCALE_DEF_VAL		0x8
+
+enum jh8100_pdm_blockx {
+	JH8100_PDM_BLK0 = 0,
+	JH8100_PDM_BLK1 = 1,
+};
+
+struct jh8100_pdm_priv {
+	struct regmap *regmap;
+	struct regmap *syscon_regmap;
+	struct device *dev;
+	struct clk *dmic_clk;
+	struct clk *icg_clk;
+	struct reset_control *rst;
+	unsigned int syscon_args[2]; /* [0]: offset, [1]: mask */
+};
+
+static const DECLARE_TLV_DB_SCALE(volume_tlv, -9450, 150, 0);
+
+static const struct snd_kcontrol_new jh8100_pdm_snd_controls[] = {
+	SOC_DOUBLE_R("DC compensation Switch", JH8100_PDM_DMIC_CTRL0,
+		     JH8100_PDM_DMIC_CTRL1, 30, 1, 0),
+	SOC_DOUBLE_R("High Pass Filter Switch", JH8100_PDM_DMIC_CTRL0,
+		     JH8100_PDM_DMIC_CTRL1, 28, 1, 0),
+	SOC_DOUBLE_R_TLV("Volume", JH8100_PDM_DMIC_CTRL0,
+			 JH8100_PDM_DMIC_CTRL1, 16, 0x3F, 1, volume_tlv),
+	SOC_DOUBLE_R("Data MSB Shift Route", JH8100_PDM_DMIC_CTRL0,
+		     JH8100_PDM_DMIC_CTRL1, 1, 7, 0),
+	SOC_DOUBLE_R("SCALE Route", JH8100_PDM_DC_SCALE0,
+		     JH8100_PDM_DC_SCALE1, 0, 0x3F, 0),
+	SOC_DOUBLE_R("DC offset Route", JH8100_PDM_DC_SCALE0,
+		     JH8100_PDM_DC_SCALE1, 8, 0xFFFFF, 0),
+};
+
+/* Left (and Right) Channel Swicth Enable */
+static void jh8100_pdm_enable_lr(struct regmap *map, u8 block,
+				 bool right)
+{
+	u16 res = JH8100_PDM_GET_CTRLX(block);
+
+	regmap_update_bits(map, res, JH8100_PDM_DMIC_RSWITCH_MASK, 0);
+
+	if (right)
+		regmap_update_bits(map, res, JH8100_PDM_DMIC_LSWITCH_MASK, 0);
+}
+
+/* Left and Right Channel Swicth Disable */
+static void jh8100_pdm_disable(struct regmap *map, u8 block)
+{
+	u16 res = JH8100_PDM_GET_CTRLX(block);
+
+	regmap_update_bits(map, res,
+			   JH8100_PDM_DMIC_RSWITCH_MASK | JH8100_PDM_DMIC_LSWITCH_MASK,
+			   JH8100_PDM_DMIC_RSWITCH_MASK | JH8100_PDM_DMIC_LSWITCH_MASK);
+}
+
+static void jh8100_pdm_disable_all(struct regmap *map)
+{
+	jh8100_pdm_disable(map, JH8100_PDM_BLK0);
+	jh8100_pdm_disable(map, JH8100_PDM_BLK1);
+}
+
+static int jh8100_pdm_dai_probe(struct snd_soc_dai *dai)
+{
+	struct jh8100_pdm_priv *priv = snd_soc_dai_get_drvdata(dai);
+
+	/* Change I2SDIN source to PDM */
+	regmap_update_bits(priv->syscon_regmap, priv->syscon_args[0],
+			   priv->syscon_args[1], priv->syscon_args[1]);
+
+	return 0;
+}
+
+static int jh8100_pdm_trigger(struct snd_pcm_substream *substream, int cmd,
+			      struct snd_soc_dai *dai)
+{
+	struct jh8100_pdm_priv *priv = snd_soc_dai_get_drvdata(dai);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		return 0;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		jh8100_pdm_disable_all(priv->regmap);
+		return 0;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int jh8100_pdm_hw_params(struct snd_pcm_substream *substream,
+				struct snd_pcm_hw_params *params,
+				struct snd_soc_dai *dai)
+{
+	struct jh8100_pdm_priv *priv = snd_soc_dai_get_drvdata(dai);
+
+	/*
+	 * 1 channel: block 0 left channel on,
+	 * 2 channels: block 0 left/right on,
+	 * 3 channels: block 0 left/right on, block 1 left on,
+	 * 4 channels: block 0 and 1 all on.
+	 */
+	switch (params_channels(params)) {
+	case 1:
+		jh8100_pdm_enable_lr(priv->regmap, JH8100_PDM_BLK0, false);
+		break;
+	case 2:
+		jh8100_pdm_enable_lr(priv->regmap, JH8100_PDM_BLK0, true);
+		break;
+	case 3:
+		jh8100_pdm_enable_lr(priv->regmap, JH8100_PDM_BLK0, true);
+		jh8100_pdm_enable_lr(priv->regmap, JH8100_PDM_BLK1, false);
+		break;
+	case 4:
+		jh8100_pdm_enable_lr(priv->regmap, JH8100_PDM_BLK0, true);
+		jh8100_pdm_enable_lr(priv->regmap, JH8100_PDM_BLK1, true);
+		break;
+
+	default:
+		dev_err(priv->dev, "channels are not supported\n");
+		return -EINVAL;
+	}
+
+	/* set pdm_mclk,  PDM MCLK = 128 * LRCLK */
+	return clk_set_rate(priv->dmic_clk, 128 * params_rate(params));
+}
+
+static const struct snd_soc_dai_ops jh8100_pdm_dai_ops = {
+	.probe		= jh8100_pdm_dai_probe,
+	.trigger	= jh8100_pdm_trigger,
+	.hw_params	= jh8100_pdm_hw_params,
+};
+
+static void jh8100_pdm_block_init(struct jh8100_pdm_priv *priv, u8 block)
+{
+	u16 ctrl = JH8100_PDM_GET_CTRLX(block);
+	u16 scale = JH8100_PDM_GET_SCALEX(block);
+
+	/* Reset */
+	regmap_update_bits(priv->regmap, ctrl,
+			   JH8100_PDM_SW_RST_MASK, 0);
+	regmap_update_bits(priv->regmap, ctrl,
+			   JH8100_PDM_SW_RST_MASK, JH8100_PDM_SW_RST_RELEASE);
+
+	/* Make sure the device is initially disabled */
+	jh8100_pdm_disable(priv->regmap, block);
+
+	/* MUTE */
+	regmap_update_bits(priv->regmap, ctrl,
+			   JH8100_PDM_DMIC_VOL_MASK, JH8100_PDM_VOL_DB_MUTE);
+
+	/* UNMUTE */
+	regmap_update_bits(priv->regmap, ctrl,
+			   JH8100_PDM_DMIC_VOL_MASK, JH8100_PDM_VOL_DB_MAX);
+
+	/* enable high pass filter */
+	regmap_update_bits(priv->regmap, ctrl,
+			   JH8100_PDM_DMIC_HPF_EN, JH8100_PDM_DMIC_HPF_EN);
+
+	/* PDM work as slave mode */
+	regmap_update_bits(priv->regmap, ctrl,
+			   JH8100_PDM_DMIC_I2S_SLAVE, JH8100_PDM_DMIC_I2S_SLAVE);
+
+	/* Enable fast mode */
+	regmap_update_bits(priv->regmap, ctrl,
+			   JH8100_PDM_DMIC_FASTMODE_MASK,
+			   JH8100_PDM_DMIC_FASTMODE_MASK);
+
+	/* Default dmic msb shift 0 */
+	regmap_update_bits(priv->regmap, ctrl,
+			   JH8100_PDM_DMIC_MSB_MASK, 0);
+
+	/* Default scale: 0x8 */
+	regmap_update_bits(priv->regmap, scale,
+			   JH8100_DMIC_SCALE_MASK, JH8100_DMIC_SCALE_DEF_VAL);
+
+	/* Default DC offset: 0xc005 */
+	regmap_update_bits(priv->regmap, scale,
+			   JH8100_DMIC_DCOFF_MASK,
+			   FIELD_PREP(JH8100_DMIC_DCOFF_MASK, JH8100_DMIC_DCOFF_DEF_VAL));
+}
+
+#define JH8100_PDM_RATES	(SNDRV_PCM_RATE_8000 | \
+				 SNDRV_PCM_RATE_11025 | \
+				 SNDRV_PCM_RATE_16000)
+
+#define JH8100_PDM_FORMATS	(SNDRV_PCM_FMTBIT_S16_LE | \
+				 SNDRV_PCM_FMTBIT_S32_LE)
+
+static struct snd_soc_dai_driver jh8100_pdm_dai_drv = {
+	.name = "PDM",
+	.id = 0,
+	.capture = {
+		.stream_name	= "Capture",
+		.channels_min	= 1,
+		.channels_max	= 4,
+		.rates		= JH8100_PDM_RATES,
+		.formats	= JH8100_PDM_FORMATS,
+	},
+	.ops = &jh8100_pdm_dai_ops,
+	.symmetric_rate = 1,
+};
+
+static int jh8100_pdm_component_probe(struct snd_soc_component *component)
+{
+	struct jh8100_pdm_priv *priv = snd_soc_component_get_drvdata(component);
+
+	snd_soc_component_init_regmap(component, priv->regmap);
+
+	return 0;
+}
+
+static int jh8100_pdm_crg_enable(struct jh8100_pdm_priv *priv)
+{
+	int ret;
+
+	ret = clk_prepare_enable(priv->icg_clk);
+	if (ret)
+		return dev_err_probe(priv->dev, ret, "failed to enable icg clock\n");
+
+	ret = reset_control_deassert(priv->rst);
+	if (ret) {
+		dev_err(priv->dev, "failed to deassert pdm_apb\n");
+		goto disable_icg;
+	}
+
+	return 0;
+
+disable_icg:
+	clk_disable_unprepare(priv->icg_clk);
+	return ret;
+}
+
+static int jh8100_pdm_crg_disable(struct jh8100_pdm_priv *priv)
+{
+	int ret = reset_control_assert(priv->rst);
+
+	if (ret)
+		return dev_err_probe(priv->dev, ret, "failed to assert pdm_apb\n");
+
+	clk_disable_unprepare(priv->icg_clk);
+	return 0;
+}
+
+static int __maybe_unused jh8100_pdm_runtime_suspend(struct device *dev)
+{
+	struct jh8100_pdm_priv *priv = dev_get_drvdata(dev);
+
+	return jh8100_pdm_crg_disable(priv);
+}
+
+static int __maybe_unused jh8100_pdm_runtime_resume(struct device *dev)
+{
+	struct jh8100_pdm_priv *priv = dev_get_drvdata(dev);
+
+	return jh8100_pdm_crg_enable(priv);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int jh8100_pdm_suspend(struct snd_soc_component *component)
+{
+	return pm_runtime_force_suspend(component->dev);
+}
+
+static int jh8100_pdm_resume(struct snd_soc_component *component)
+{
+	return pm_runtime_force_resume(component->dev);
+}
+#else
+#define jh8100_pdm_suspend	NULL
+#define jh8100_pdm_resume	NULL
+#endif
+
+static const struct snd_soc_component_driver jh8100_pdm_component_drv = {
+	.name = "jh8100-pdm",
+	.probe = jh8100_pdm_component_probe,
+	.suspend = jh8100_pdm_suspend,
+	.resume = jh8100_pdm_resume,
+	.controls = jh8100_pdm_snd_controls,
+	.num_controls = ARRAY_SIZE(jh8100_pdm_snd_controls),
+};
+
+static const struct regmap_config jh8100_pdm_regmap_cfg = {
+	.reg_bits	= 32,
+	.val_bits	= 32,
+	.reg_stride	= 4,
+	.max_register	= 0x20,
+};
+
+static int jh8100_pdm_crg_init(struct jh8100_pdm_priv *priv)
+{
+	priv->dmic_clk = devm_clk_get(priv->dev, "dmic");
+	if (IS_ERR(priv->dmic_clk))
+		return dev_err_probe(priv->dev, PTR_ERR(priv->dmic_clk),
+				     "failed to get dmic clock.\n");
+
+	priv->icg_clk = devm_clk_get(priv->dev, "icg");
+	if (IS_ERR(priv->icg_clk))
+		return dev_err_probe(priv->dev, PTR_ERR(priv->icg_clk),
+				     "failed to get icg clock.\n");
+
+	priv->rst = devm_reset_control_get_exclusive(priv->dev, NULL);
+	if (IS_ERR(priv->rst))
+		return dev_err_probe(priv->dev, PTR_ERR(priv->rst), "failed to get pdm reset\n");
+
+	return jh8100_pdm_crg_enable(priv);
+}
+
+static int jh8100_pdm_probe(struct platform_device *pdev)
+{
+	struct jh8100_pdm_priv *priv;
+	void __iomem *base;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	platform_set_drvdata(pdev, priv);
+
+	priv->regmap = devm_regmap_init_mmio(&pdev->dev, base, &jh8100_pdm_regmap_cfg);
+	if (IS_ERR(priv->regmap))
+		return dev_err_probe(&pdev->dev, PTR_ERR(priv->regmap),
+				     "failed to init regmap\n");
+
+	priv->dev = &pdev->dev;
+	ret = jh8100_pdm_crg_init(priv);
+	if (ret)
+		return ret;
+
+	priv->syscon_regmap = syscon_regmap_lookup_by_phandle_args(pdev->dev.of_node,
+								   "starfive,syscon",
+								   2, priv->syscon_args);
+	if (IS_ERR(priv->syscon_regmap))
+		return dev_err_probe(&pdev->dev, PTR_ERR(priv->syscon_regmap),
+				     "get the syscon regmap failed\n");
+
+	ret = devm_snd_soc_register_component(&pdev->dev, &jh8100_pdm_component_drv,
+					      &jh8100_pdm_dai_drv, 1);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret, "failed to register pdm dai\n");
+
+	jh8100_pdm_block_init(priv, JH8100_PDM_BLK0);
+	jh8100_pdm_block_init(priv, JH8100_PDM_BLK1);
+
+	pm_runtime_set_autosuspend_delay(&pdev->dev, 100);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	return 0;
+}
+
+static int jh8100_pdm_remove(struct platform_device *pdev)
+{
+	struct jh8100_pdm_priv *priv = platform_get_drvdata(pdev);
+
+	/* Change I2SDIN source to default (PAD) */
+	regmap_update_bits(priv->syscon_regmap, priv->syscon_args[0],
+			   priv->syscon_args[1], 0);
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static const struct of_device_id jh8100_pdm_of_match[] = {
+	{.compatible = "starfive,jh8100-pdm",},
+	{}
+};
+MODULE_DEVICE_TABLE(of, jh8100_pdm_of_match);
+
+static const struct dev_pm_ops jh8100_pdm_pm_ops = {
+	SET_RUNTIME_PM_OPS(jh8100_pdm_runtime_suspend,
+			   jh8100_pdm_runtime_resume, NULL)
+};
+
+static struct platform_driver jh8100_pdm_driver = {
+	.driver = {
+		.name = "jh8100-pdm",
+		.of_match_table = jh8100_pdm_of_match,
+		.pm = &jh8100_pdm_pm_ops,
+	},
+	.probe = jh8100_pdm_probe,
+	.remove = jh8100_pdm_remove,
+};
+module_platform_driver(jh8100_pdm_driver);
+
+MODULE_AUTHOR("Xingyu Wu <xingyu.wu@starfivetech.com>");
+MODULE_AUTHOR("Walker Chen <walker.chen@starfivetech.com>");
+MODULE_DESCRIPTION("StarFive JH8100 PDM Controller Driver");
+MODULE_LICENSE("GPL");