ASoC: Add AK4375 support

AK4375 is a 32-bit stereo DAC with headphones amplifier.
There's no documentation for it on akm.com, and only a brief
datasheet can be found floating on the internets [1].

Thanks to Oriane BAYERD <obayerd@eurocomposant.fr>
for finally answering my inquiries through akm.com, if only to tell
me that this chip is EOL following AKM factory burning in october 2020
and thus no detailed documentation is available anymore...

AK4331 is advertised [2] as pin and register compatible with AK4375
so some scraps of its datasheet were used and this driver might be
used as a base for it, but this is totally untested.

So this driver is mainly based on downstream code [3] and [4]
by Hu Jin from AKM (no known email).

Tested on msm8916-alcatel-idol347 and msm8939-alcatel-idol3,
which both use PLL driven clock with bypass of SRC (sample rate
converter), so only this setup is supported for now.

[1] https://datasheetspdf.com/pdf-file/1400317/AKM/AK4375A/1
[2] https://www.akm.com/content/dam/documents/products/audio/audio-dac/ak4331ecb/ak4331ecb-en-datasheet.pdf
[3] https://github.com/msm8916-mainline/android_kernel_qcom_msm8916/blob/alcatel-idol347/sound/soc/codecs/idol347/ak4375.c
[4] https://github.com/msm8916-mainline/android_kernel_qcom_msm8916/blob/alcatel-idol347/sound/soc/codecs/ak4375.c

Signed-off-by: Vincent Knecht <vincent.knecht@mailoo.org>
Link: https://lore.kernel.org/r/20211220193725.2650356-2-vincent.knecht@mailoo.org
Signed-off-by: Mark Brown <broonie@kernel.org>

3 files changed, 632 insertions, 0 deletions

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 22836ca9b478..5fe9ec924864 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -41,6 +41,7 @@ config SND_SOC_ALL_CODECS
 	imply SND_SOC_ADS117X
 	imply SND_SOC_AK4104
 	imply SND_SOC_AK4118
+	imply SND_SOC_AK4375
 	imply SND_SOC_AK4458
 	imply SND_SOC_AK4535
 	imply SND_SOC_AK4554
@@ -523,6 +524,16 @@ config SND_SOC_AK4118
 	depends on I2C
 	select REGMAP_I2C
 
+config SND_SOC_AK4375
+	tristate "AKM AK4375 CODEC"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  Enable support for the Asahi-Kasei AK4375 codec.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-soc-ak4375.
+
 config SND_SOC_AK4458
 	tristate "AKM AK4458 CODEC"
 	depends on I2C
diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index 24bc6b34ba2f..8dbdf3518bda 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -34,6 +34,7 @@ snd-soc-adav803-objs := adav803.o
 snd-soc-ads117x-objs := ads117x.o
 snd-soc-ak4104-objs := ak4104.o
 snd-soc-ak4118-objs := ak4118.o
+snd-soc-ak4375-objs := ak4375.o
 snd-soc-ak4458-objs := ak4458.o
 snd-soc-ak4535-objs := ak4535.o
 snd-soc-ak4554-objs := ak4554.o
@@ -371,6 +372,7 @@ obj-$(CONFIG_SND_SOC_ADAV803)  += snd-soc-adav803.o
 obj-$(CONFIG_SND_SOC_ADS117X)	+= snd-soc-ads117x.o
 obj-$(CONFIG_SND_SOC_AK4104)	+= snd-soc-ak4104.o
 obj-$(CONFIG_SND_SOC_AK4118)	+= snd-soc-ak4118.o
+obj-$(CONFIG_SND_SOC_AK4375)	+= snd-soc-ak4375.o
 obj-$(CONFIG_SND_SOC_AK4458)	+= snd-soc-ak4458.o
 obj-$(CONFIG_SND_SOC_AK4535)	+= snd-soc-ak4535.o
 obj-$(CONFIG_SND_SOC_AK4554)	+= snd-soc-ak4554.o
diff --git a/sound/soc/codecs/ak4375.c b/sound/soc/codecs/ak4375.c
new file mode 100644
index 000000000000..a893aff42a01
--- /dev/null
+++ b/sound/soc/codecs/ak4375.c
@@ -0,0 +1,619 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/*
+ * Based on code by Hu Jin
+ * Copyright (C) 2014 Asahi Kasei Microdevices Corporation
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+#include <sound/soc.h>
+#include <sound/tlv.h>
+
+/* Registers and fields */
+#define AK4375_00_POWER_MANAGEMENT1		0x00
+#define PMPLL					BIT(0)	/* 0: PLL off, 1: PLL on */
+#define AK4375_01_POWER_MANAGEMENT2		0x01
+#define PMCP1					BIT(0)	/* Charge Pump 1: LDO1 and DAC */
+#define PMCP2					BIT(1)	/* Charge Pump 2: Class-G HP Amp */
+#define PMLDO1P					BIT(4)
+#define PMLDO1N					BIT(5)
+#define PMLDO					(PMLDO1P | PMLDO1N)
+#define AK4375_02_POWER_MANAGEMENT3		0x02
+#define AK4375_03_POWER_MANAGEMENT4		0x03
+#define AK4375_04_OUTPUT_MODE_SETTING		0x04
+#define AK4375_05_CLOCK_MODE_SELECT		0x05
+#define FS_MASK					GENMASK(4, 0)
+#define FS_8KHZ					0x00
+#define FS_11_025KHZ				0x01
+#define FS_16KHZ				0x04
+#define FS_22_05KHZ				0x05
+#define FS_32KHZ				0x08
+#define FS_44_1KHZ				0x09
+#define FS_48KHZ				0x0a
+#define FS_88_2KHZ				0x0d
+#define FS_96KHZ				0x0e
+#define FS_176_4KHZ				0x11
+#define FS_192KHZ				0x12
+#define CM_MASK					GENMASK(6, 5)	/* For SRC Bypass mode */
+#define CM_0					(0x0 << 5)
+#define CM_1					(0x1 << 5)
+#define CM_2					(0x2 << 5)
+#define CM_3					(0x3 << 5)
+#define AK4375_06_DIGITAL_FILTER_SELECT		0x06
+#define DADFSEL					BIT(5)	/* 0: in SRC Bypass mode, 1: in SRC mode */
+#define DASL					BIT(6)
+#define DASD					BIT(7)
+#define AK4375_07_DAC_MONO_MIXING		0x07
+#define DACMUTE_MASK				(GENMASK(5, 4) | GENMASK(1, 0)) /* Clear to mute */
+#define AK4375_08_JITTER_CLEANER_SETTING1	0x08
+#define AK4375_09_JITTER_CLEANER_SETTING2	0x09
+#define AK4375_0A_JITTER_CLEANER_SETTING3	0x0a
+#define SELDAIN					BIT(1)	/* 0: SRC Bypass mode, 1: SRC mode */
+#define XCKSEL					BIT(6)	/* 0: PLL0, 1: MCKI */
+#define XCKCPSEL				BIT(7)	/* Should be equal to SELDAIN and XCKSEL */
+#define AK4375_0B_LCH_OUTPUT_VOLUME		0x0b
+#define AK4375_0C_RCH_OUTPUT_VOLUME		0x0c
+#define AK4375_0D_HP_VOLUME_CONTROL		0x0d
+#define AK4375_0E_PLL_CLK_SOURCE_SELECT		0x0e
+#define PLS					BIT(0)	/* 0: MCKI, 1: BCLK */
+#define AK4375_0F_PLL_REF_CLK_DIVIDER1		0x0f	/* Reference clock divider [15:8] bits */
+#define AK4375_10_PLL_REF_CLK_DIVIDER2		0x10	/* Reference clock divider [7:0] bis */
+#define AK4375_11_PLL_FB_CLK_DIVIDER1		0x11	/* Feedback clock divider [15:8] bits */
+#define AK4375_12_PLL_FB_CLK_DIVIDER2		0x12	/* Feedback clock divider [7:0] bits */
+#define AK4375_13_SRC_CLK_SOURCE		0x13	/* SRC Bypass: SRCCKS=XCKSEL=SELDAIN=0 */
+#define SRCCKS					BIT(0)	/* SRC Clock source 0: MCKI, 1: PLL0 */
+#define DIV					BIT(4)
+#define AK4375_14_DAC_CLK_DIVIDER		0x14
+#define AK4375_15_AUDIO_IF_FORMAT		0x15
+#define DEVICEID_MASK				GENMASK(7, 5)
+#define AK4375_24_MODE_CONTROL			0x24
+
+#define AK4375_PLL_FREQ_OUT_112896000		112896000	/* 44.1 kHz base rate */
+#define AK4375_PLL_FREQ_OUT_122880000		122880000	/* 32 and 48 kHz base rates */
+
+#define DEVICEID_AK4375				0x00
+#define DEVICEID_AK4375A			0x01
+#define DEVICEID_AK4376A			0x02
+#define DEVICEID_AK4377				0x03
+#define DEVICEID_AK4331				0x07
+
+static const char * const supply_names[] = {
+	"avdd", "tvdd"
+};
+
+struct ak4375_drvdata {
+	struct snd_soc_dai_driver *dai_drv;
+	const struct snd_soc_component_driver *comp_drv;
+};
+
+struct ak4375_priv {
+	struct device *dev;
+	struct regmap *regmap;
+	struct gpio_desc *pdn_gpiod;
+	struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
+	unsigned int rate;
+	unsigned int pld;
+	u8 mute_save;
+};
+
+static const struct reg_default ak4375_reg_defaults[] = {
+	{ 0x00, 0x00 }, { 0x01, 0x00 }, { 0x02, 0x00 },
+	{ 0x03, 0x00 }, { 0x04, 0x00 }, { 0x05, 0x00 },
+	{ 0x06, 0x00 }, { 0x07, 0x00 }, { 0x08, 0x00 },
+	{ 0x09, 0x00 }, { 0x0a, 0x00 }, { 0x0b, 0x19 },
+	{ 0x0c, 0x19 }, { 0x0d, 0x75 }, { 0x0e, 0x01 },
+	{ 0x0f, 0x00 }, { 0x10, 0x00 }, { 0x11, 0x00 },
+	{ 0x12, 0x00 }, { 0x13, 0x00 }, { 0x14, 0x00 },
+	{ 0x15, 0x00 }, { 0x24, 0x00 },
+};
+
+/*
+ * Output Digital volume control:
+ * from -12.5 to 3 dB in 0.5 dB steps (mute instead of -12.5 dB)
+ */
+static DECLARE_TLV_DB_SCALE(dac_tlv, -1250, 50, 0);
+
+/*
+ * HP-Amp Analog volume control:
+ * from -4.2 to 6 dB in 2 dB steps (mute instead of -4.2 dB)
+ */
+static DECLARE_TLV_DB_SCALE(hpg_tlv, -4200, 20, 0);
+
+static const char * const ak4375_ovolcn_select_texts[]	= { "Dependent", "Independent" };
+static const char * const ak4375_mdac_select_texts[]	= { "x1", "x1/2" };
+static const char * const ak4375_inv_select_texts[]	= { "Normal", "Inverting" };
+static const char * const ak4375_cpmode_select_texts[]	= {
+	"Automatic Switching",
+	"+-VDD Operation",
+	"+-1/2VDD Operation"
+};
+
+/*
+ * DASD, DASL bits Digital Filter Setting
+ * 0, 0 : Sharp Roll-Off Filter
+ * 0, 1 : Slow Roll-Off Filter
+ * 1, 0 : Short delay Sharp Roll-Off Filter
+ * 1, 1 : Short delay Slow Roll-Off Filter
+ */
+static const char * const ak4375_digfil_select_texts[] = {
+	"Sharp Roll-Off Filter",
+	"Slow Roll-Off Filter",
+	"Short delay Sharp Roll-Off Filter",
+	"Short delay Slow Roll-Off Filter",
+};
+
+static const struct soc_enum ak4375_ovolcn_enum =
+	SOC_ENUM_SINGLE(AK4375_0B_LCH_OUTPUT_VOLUME, 7,
+			ARRAY_SIZE(ak4375_ovolcn_select_texts), ak4375_ovolcn_select_texts);
+static const struct soc_enum ak4375_mdacl_enum =
+	SOC_ENUM_SINGLE(AK4375_07_DAC_MONO_MIXING, 2,
+			ARRAY_SIZE(ak4375_mdac_select_texts), ak4375_mdac_select_texts);
+static const struct soc_enum ak4375_mdacr_enum =
+	SOC_ENUM_SINGLE(AK4375_07_DAC_MONO_MIXING, 6,
+			ARRAY_SIZE(ak4375_mdac_select_texts), ak4375_mdac_select_texts);
+static const struct soc_enum ak4375_invl_enum =
+	SOC_ENUM_SINGLE(AK4375_07_DAC_MONO_MIXING, 3,
+			ARRAY_SIZE(ak4375_inv_select_texts), ak4375_inv_select_texts);
+static const struct soc_enum ak4375_invr_enum =
+	SOC_ENUM_SINGLE(AK4375_07_DAC_MONO_MIXING, 7,
+			ARRAY_SIZE(ak4375_inv_select_texts), ak4375_inv_select_texts);
+static const struct soc_enum ak4375_cpmode_enum =
+	SOC_ENUM_SINGLE(AK4375_03_POWER_MANAGEMENT4, 2,
+			ARRAY_SIZE(ak4375_cpmode_select_texts), ak4375_cpmode_select_texts);
+static const struct soc_enum ak4375_digfil_enum =
+	SOC_ENUM_SINGLE(AK4375_06_DIGITAL_FILTER_SELECT, 6,
+			ARRAY_SIZE(ak4375_digfil_select_texts), ak4375_digfil_select_texts);
+
+static const struct snd_kcontrol_new ak4375_snd_controls[] = {
+	SOC_DOUBLE_R_TLV("Digital Output Volume", AK4375_0B_LCH_OUTPUT_VOLUME,
+			 AK4375_0C_RCH_OUTPUT_VOLUME, 0, 0x1f, 0, dac_tlv),
+	SOC_SINGLE_TLV("HP-Amp Analog Volume",
+		       AK4375_0D_HP_VOLUME_CONTROL, 0, 0x1f, 0, hpg_tlv),
+
+	SOC_ENUM("Digital Volume Control", ak4375_ovolcn_enum),
+	SOC_ENUM("DACL Signal Level", ak4375_mdacl_enum),
+	SOC_ENUM("DACR Signal Level", ak4375_mdacr_enum),
+	SOC_ENUM("DACL Signal Invert", ak4375_invl_enum),
+	SOC_ENUM("DACR Signal Invert", ak4375_invr_enum),
+	SOC_ENUM("Charge Pump Mode", ak4375_cpmode_enum),
+	SOC_ENUM("DAC Digital Filter Mode", ak4375_digfil_enum),
+};
+
+static const struct snd_kcontrol_new ak4375_hpl_mixer_controls[] = {
+	SOC_DAPM_SINGLE("LDACL Switch", AK4375_07_DAC_MONO_MIXING, 0, 1, 0),
+	SOC_DAPM_SINGLE("RDACL Switch", AK4375_07_DAC_MONO_MIXING, 1, 1, 0),
+};
+
+static const struct snd_kcontrol_new ak4375_hpr_mixer_controls[] = {
+	SOC_DAPM_SINGLE("LDACR Switch", AK4375_07_DAC_MONO_MIXING, 4, 1, 0),
+	SOC_DAPM_SINGLE("RDACR Switch", AK4375_07_DAC_MONO_MIXING, 5, 1, 0),
+};
+
+static int ak4375_dac_event(struct snd_soc_dapm_widget *w,
+			    struct snd_kcontrol *kcontrol, int event)
+{
+	struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
+
+	switch (event) {
+	case SND_SOC_DAPM_PRE_PMU:
+		snd_soc_component_update_bits(component, AK4375_00_POWER_MANAGEMENT1, PMPLL, PMPLL);
+		snd_soc_component_update_bits(component, AK4375_01_POWER_MANAGEMENT2, PMCP1, PMCP1);
+		usleep_range(6500, 7000);
+		snd_soc_component_update_bits(component, AK4375_01_POWER_MANAGEMENT2, PMLDO, PMLDO);
+		usleep_range(1000, 2000);
+		break;
+	case SND_SOC_DAPM_POST_PMU:
+		snd_soc_component_update_bits(component, AK4375_01_POWER_MANAGEMENT2, PMCP2, PMCP2);
+		usleep_range(4500, 5000);
+		break;
+	case SND_SOC_DAPM_PRE_PMD:
+		snd_soc_component_update_bits(component, AK4375_01_POWER_MANAGEMENT2, PMCP2, 0x0);
+		break;
+	case SND_SOC_DAPM_POST_PMD:
+		snd_soc_component_update_bits(component, AK4375_01_POWER_MANAGEMENT2, PMLDO, 0x0);
+		snd_soc_component_update_bits(component, AK4375_01_POWER_MANAGEMENT2, PMCP1, 0x0);
+		snd_soc_component_update_bits(component, AK4375_00_POWER_MANAGEMENT1, PMPLL, 0x0);
+		break;
+	}
+
+	return 0;
+}
+
+static const struct snd_soc_dapm_widget ak4375_dapm_widgets[] = {
+	SND_SOC_DAPM_DAC_E("DAC", NULL, AK4375_02_POWER_MANAGEMENT3, 0, 0, ak4375_dac_event,
+			   SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMU |
+			   SND_SOC_DAPM_PRE_PMD | SND_SOC_DAPM_POST_PMD),
+
+	SND_SOC_DAPM_AIF_IN("SDTI", "HiFi Playback", 0, SND_SOC_NOPM, 0, 0),
+
+	SND_SOC_DAPM_OUTPUT("HPL"),
+	SND_SOC_DAPM_OUTPUT("HPR"),
+
+	SND_SOC_DAPM_MIXER("HPR Mixer", AK4375_03_POWER_MANAGEMENT4, 1, 0,
+			   &ak4375_hpr_mixer_controls[0], ARRAY_SIZE(ak4375_hpr_mixer_controls)),
+	SND_SOC_DAPM_MIXER("HPL Mixer", AK4375_03_POWER_MANAGEMENT4, 0, 0,
+			   &ak4375_hpl_mixer_controls[0], ARRAY_SIZE(ak4375_hpl_mixer_controls)),
+};
+
+static const struct snd_soc_dapm_route ak4375_intercon[] = {
+	{ "DAC",	NULL,		"SDTI" },
+
+	{ "HPL Mixer",	"LDACL Switch",	"DAC" },
+	{ "HPL Mixer",	"RDACL Switch",	"DAC" },
+	{ "HPR Mixer",	"LDACR Switch",	"DAC" },
+	{ "HPR Mixer",	"RDACR Switch",	"DAC" },
+
+	{ "HPL",	NULL,		"HPL Mixer" },
+	{ "HPR",	NULL,		"HPR Mixer" },
+};
+
+static int ak4375_hw_params(struct snd_pcm_substream *substream,
+			    struct snd_pcm_hw_params *params,
+			    struct snd_soc_dai *dai)
+{
+	struct snd_soc_component *component = dai->component;
+	struct ak4375_priv *ak4375 = snd_soc_component_get_drvdata(component);
+	unsigned int freq_in, freq_out;
+
+	ak4375->rate = params_rate(params);
+
+	if (ak4375->rate <= 96000)
+		ak4375->pld = 0;
+	else
+		ak4375->pld = 1;
+
+	freq_in = 32 * ak4375->rate / (ak4375->pld + 1);
+
+	if ((ak4375->rate % 8000) == 0)
+		freq_out = AK4375_PLL_FREQ_OUT_122880000;
+	else
+		freq_out = AK4375_PLL_FREQ_OUT_112896000;
+
+	return snd_soc_dai_set_pll(dai, 0, 0, freq_in, freq_out);
+}
+
+static int ak4375_dai_set_pll(struct snd_soc_dai *dai, int pll_id, int source,
+			      unsigned int freq_in, unsigned int freq_out)
+{
+	struct snd_soc_component *component = dai->component;
+	struct ak4375_priv *ak4375 = snd_soc_component_get_drvdata(component);
+	unsigned int mclk, plm, mdiv, div;
+	u8 cms, fs, cm;
+
+	cms = snd_soc_component_read(component, AK4375_05_CLOCK_MODE_SELECT);
+	fs = cms & ~FS_MASK;
+	cm = cms & ~CM_MASK;
+
+	switch (ak4375->rate) {
+	case 8000:
+		fs |= FS_8KHZ;
+		break;
+	case 11025:
+		fs |= FS_11_025KHZ;
+		break;
+	case 16000:
+		fs |= FS_16KHZ;
+		break;
+	case 22050:
+		fs |= FS_22_05KHZ;
+		break;
+	case 32000:
+		fs |= FS_32KHZ;
+		break;
+	case 44100:
+		fs |= FS_44_1KHZ;
+		break;
+	case 48000:
+		fs |= FS_48KHZ;
+		break;
+	case 88200:
+		fs |= FS_88_2KHZ;
+		break;
+	case 96000:
+		fs |= FS_96KHZ;
+		break;
+	case 176400:
+		fs |= FS_176_4KHZ;
+		break;
+	case 192000:
+		fs |= FS_192KHZ;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (ak4375->rate <= 24000) {
+		cm |= CM_1;
+		mclk = 512 * ak4375->rate;
+		mdiv = freq_out / mclk - 1;
+		div = 0;
+	} else if (ak4375->rate <= 96000) {
+		cm |= CM_0;
+		mclk = 256 * ak4375->rate;
+		mdiv = freq_out / mclk - 1;
+		div = 0;
+	} else {
+		cm |= CM_3;
+		mclk = 128 * ak4375->rate;
+		mdiv = 4;
+		div = 1;
+	}
+
+	/* Writing both fields in one go seems to make playback choppy on start */
+	snd_soc_component_update_bits(component, AK4375_05_CLOCK_MODE_SELECT, FS_MASK, fs);
+	snd_soc_component_update_bits(component, AK4375_05_CLOCK_MODE_SELECT, CM_MASK, cm);
+
+	snd_soc_component_write(component, AK4375_0F_PLL_REF_CLK_DIVIDER1,
+				(ak4375->pld & 0xff00) >> 8);
+	snd_soc_component_write(component, AK4375_10_PLL_REF_CLK_DIVIDER2,
+				ak4375->pld & 0x00ff);
+
+	plm = freq_out / freq_in - 1;
+	snd_soc_component_write(component, AK4375_11_PLL_FB_CLK_DIVIDER1, (plm & 0xff00) >> 8);
+	snd_soc_component_write(component, AK4375_12_PLL_FB_CLK_DIVIDER2, plm & 0x00ff);
+
+	snd_soc_component_update_bits(component, AK4375_13_SRC_CLK_SOURCE, DIV, div);
+
+	/* SRCCKS bit: force to 1 for SRC PLL source clock */
+	snd_soc_component_update_bits(component, AK4375_13_SRC_CLK_SOURCE, SRCCKS, SRCCKS);
+
+	snd_soc_component_write(component, AK4375_14_DAC_CLK_DIVIDER, mdiv);
+
+	dev_dbg(ak4375->dev, "rate=%d mclk=%d f_in=%d f_out=%d PLD=%d PLM=%d MDIV=%d DIV=%d\n",
+		ak4375->rate, mclk, freq_in, freq_out, ak4375->pld, plm, mdiv, div);
+
+	return 0;
+}
+
+static int ak4375_mute(struct snd_soc_dai *dai, int mute, int direction)
+{
+	struct snd_soc_component *component = dai->component;
+	struct ak4375_priv *ak4375 = snd_soc_component_get_drvdata(component);
+	u8 val = snd_soc_component_read(component, AK4375_07_DAC_MONO_MIXING);
+
+	dev_dbg(ak4375->dev, "mute=%d val=%d\n", mute, val);
+
+	if (mute) {
+		ak4375->mute_save = val & DACMUTE_MASK;
+		val &= ~DACMUTE_MASK;
+	} else {
+		val |= ak4375->mute_save;
+	}
+
+	snd_soc_component_write(component, AK4375_07_DAC_MONO_MIXING, val);
+
+	return 0;
+}
+
+#define AK4375_RATES	(SNDRV_PCM_RATE_8000_48000 |\
+			 SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000 |\
+			 SNDRV_PCM_RATE_176400 | SNDRV_PCM_RATE_192000)
+
+#define AK4375_FORMATS	(SNDRV_PCM_FMTBIT_S16_LE |\
+			 SNDRV_PCM_FMTBIT_S24_LE |\
+			 SNDRV_PCM_FMTBIT_S32_LE)
+
+static const struct snd_soc_dai_ops ak4375_dai_ops = {
+	.hw_params	= ak4375_hw_params,
+	.mute_stream	= ak4375_mute,
+	.set_pll	= ak4375_dai_set_pll,
+};
+
+static struct snd_soc_dai_driver ak4375_dai = {
+	.name = "ak4375-hifi",
+	.playback = {
+		.stream_name	= "HiFi Playback",
+		.channels_min	= 1,
+		.channels_max	= 2,
+		.rates		= AK4375_RATES,
+		.rate_min	= 8000,
+		.rate_max	= 192000,
+		.formats	= AK4375_FORMATS,
+	},
+	.ops = &ak4375_dai_ops,
+};
+
+static void ak4375_power_off(struct ak4375_priv *ak4375)
+{
+	gpiod_set_value_cansleep(ak4375->pdn_gpiod, 0);
+	usleep_range(1000, 2000);
+
+	regulator_bulk_disable(ARRAY_SIZE(ak4375->supplies), ak4375->supplies);
+}
+
+static int ak4375_power_on(struct ak4375_priv *ak4375)
+{
+	int ret;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(ak4375->supplies), ak4375->supplies);
+	if (ret < 0) {
+		dev_err(ak4375->dev, "Failed to enable regulators: %d\n", ret);
+		return ret;
+	}
+
+	usleep_range(3000, 4000);
+
+	gpiod_set_value_cansleep(ak4375->pdn_gpiod, 1);
+	usleep_range(1000, 2000);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int __maybe_unused ak4375_runtime_suspend(struct device *dev)
+{
+	struct ak4375_priv *ak4375 = dev_get_drvdata(dev);
+
+	regcache_cache_only(ak4375->regmap, true);
+	ak4375_power_off(ak4375);
+
+	return 0;
+}
+
+static int __maybe_unused ak4375_runtime_resume(struct device *dev)
+{
+	struct ak4375_priv *ak4375 = dev_get_drvdata(dev);
+	int ret;
+
+	ret = ak4375_power_on(ak4375);
+	if (ret < 0)
+		return ret;
+
+	regcache_cache_only(ak4375->regmap, false);
+	regcache_mark_dirty(ak4375->regmap);
+
+	return regcache_sync(ak4375->regmap);
+}
+#endif /* CONFIG_PM */
+
+static const struct snd_soc_component_driver soc_codec_dev_ak4375 = {
+	.controls		= ak4375_snd_controls,
+	.num_controls		= ARRAY_SIZE(ak4375_snd_controls),
+	.dapm_widgets		= ak4375_dapm_widgets,
+	.num_dapm_widgets	= ARRAY_SIZE(ak4375_dapm_widgets),
+	.dapm_routes		= ak4375_intercon,
+	.num_dapm_routes	= ARRAY_SIZE(ak4375_intercon),
+	.idle_bias_on		= 1,
+	.use_pmdown_time	= 1,
+	.endianness		= 1,
+	.non_legacy_dai_naming	= 1,
+};
+
+static const struct regmap_config ak4375_regmap = {
+	.reg_bits		= 8,
+	.val_bits		= 8,
+	.max_register		= AK4375_24_MODE_CONTROL,
+	.reg_defaults		= ak4375_reg_defaults,
+	.num_reg_defaults	= ARRAY_SIZE(ak4375_reg_defaults),
+	.cache_type		= REGCACHE_RBTREE,
+};
+
+static const struct ak4375_drvdata ak4375_drvdata = {
+	.dai_drv = &ak4375_dai,
+	.comp_drv = &soc_codec_dev_ak4375,
+};
+
+static const struct dev_pm_ops ak4375_pm = {
+	SET_RUNTIME_PM_OPS(ak4375_runtime_suspend, ak4375_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
+};
+
+static int ak4375_i2c_probe(struct i2c_client *i2c)
+{
+	struct ak4375_priv *ak4375;
+	const struct ak4375_drvdata *drvdata;
+	unsigned int deviceid;
+	int ret, i;
+
+	ak4375 = devm_kzalloc(&i2c->dev, sizeof(*ak4375), GFP_KERNEL);
+	if (!ak4375)
+		return -ENOMEM;
+
+	ak4375->regmap = devm_regmap_init_i2c(i2c, &ak4375_regmap);
+	if (IS_ERR(ak4375->regmap))
+		return PTR_ERR(ak4375->regmap);
+
+	i2c_set_clientdata(i2c, ak4375);
+	ak4375->dev = &i2c->dev;
+
+	drvdata = of_device_get_match_data(&i2c->dev);
+
+	for (i = 0; i < ARRAY_SIZE(supply_names); i++)
+		ak4375->supplies[i].supply = supply_names[i];
+
+	ret = devm_regulator_bulk_get(ak4375->dev, ARRAY_SIZE(ak4375->supplies), ak4375->supplies);
+	if (ret < 0) {
+		dev_err(ak4375->dev, "Failed to get regulators: %d\n", ret);
+		return ret;
+	}
+
+	ak4375->pdn_gpiod = devm_gpiod_get_optional(ak4375->dev, "pdn", GPIOD_OUT_LOW);
+	if (IS_ERR(ak4375->pdn_gpiod))
+		return dev_err_probe(ak4375->dev, PTR_ERR(ak4375->pdn_gpiod),
+				     "failed to get pdn\n");
+
+	ret = ak4375_power_on(ak4375);
+	if (ret < 0)
+		return ret;
+
+	/* Don't read deviceid from cache */
+	regcache_cache_bypass(ak4375->regmap, true);
+
+	ret = regmap_read(ak4375->regmap, AK4375_15_AUDIO_IF_FORMAT, &deviceid);
+	if (ret < 0) {
+		dev_err(ak4375->dev, "unable to read DEVICEID!\n");
+		return ret;
+	}
+
+	regcache_cache_bypass(ak4375->regmap, false);
+
+	deviceid = (deviceid & DEVICEID_MASK) >> 5;
+
+	switch (deviceid) {
+	case DEVICEID_AK4331:
+		dev_err(ak4375->dev, "found untested AK4331\n");
+		return -EINVAL;
+	case DEVICEID_AK4375:
+		dev_dbg(ak4375->dev, "found AK4375\n");
+		break;
+	case DEVICEID_AK4375A:
+		dev_dbg(ak4375->dev, "found AK4375A\n");
+		break;
+	case DEVICEID_AK4376A:
+		dev_err(ak4375->dev, "found unsupported AK4376/A!\n");
+		return -EINVAL;
+	case DEVICEID_AK4377:
+		dev_err(ak4375->dev, "found unsupported AK4377!\n");
+		return -EINVAL;
+	default:
+		dev_err(ak4375->dev, "unrecognized DEVICEID!\n");
+		return -EINVAL;
+	}
+
+	pm_runtime_set_active(ak4375->dev);
+	pm_runtime_enable(ak4375->dev);
+
+	ret = devm_snd_soc_register_component(ak4375->dev, drvdata->comp_drv,
+					      drvdata->dai_drv, 1);
+	if (ret < 0) {
+		dev_err(ak4375->dev, "Failed to register CODEC: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int ak4375_i2c_remove(struct i2c_client *i2c)
+{
+	pm_runtime_disable(&i2c->dev);
+
+	return 0;
+}
+
+static const struct of_device_id ak4375_of_match[] = {
+	{ .compatible = "asahi-kasei,ak4375", .data = &ak4375_drvdata },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ak4375_of_match);
+
+static struct i2c_driver ak4375_i2c_driver = {
+	.driver = {
+		.name = "ak4375",
+		.pm = &ak4375_pm,
+		.of_match_table = ak4375_of_match,
+	},
+	.probe_new = ak4375_i2c_probe,
+	.remove = ak4375_i2c_remove,
+};
+module_i2c_driver(ak4375_i2c_driver);
+
+MODULE_AUTHOR("Vincent Knecht <vincent.knecht@mailoo.org>");
+MODULE_DESCRIPTION("ASoC AK4375 DAC driver");
+MODULE_LICENSE("GPL");