ASoC: ak5558: Add support for AK5558 ADC driver

AK5558 is a 32-bit, 768 kHZ sampling, differential input ADC
for digital audio systems.

Datasheet is available at:

https://www.akm.com/akm/en/file/datasheet/AK5558VN.pdf

Initial patch includes support for normal and TDM modes.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Junichi Wakasugi <wakasugi.jb@om.asahi-kasei.co.jp>
[initial coding for 3.18 kernel]
Signed-off-by: Mihai Serban <mihai.serban@nxp.com>
[cleanups and porting to 4.9 kernel]
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
[tdm support]
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
[pm support, cleanups and porting to latest kernel]
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/Kconfig

@@ -42,6 +42,7 @@ config SND_SOC_ALL_CODECS
 	select SND_SOC_AK4642 if I2C
 	select SND_SOC_AK4671 if I2C
 	select SND_SOC_AK5386
+	select SND_SOC_AK5558 if I2C
 	select SND_SOC_ALC5623 if I2C
 	select SND_SOC_ALC5632 if I2C
 	select SND_SOC_BT_SCO
@@ -398,6 +399,11 @@ config SND_SOC_AK4671
 config SND_SOC_AK5386
 	tristate "AKM AK5638 CODEC"
 
+config SND_SOC_AK5558
+	tristate "AKM AK5558 CODEC"
+	depends on I2C
+	select REGMAP_I2C
+
 config SND_SOC_ALC5623
        tristate "Realtek ALC5623 CODEC"
 	depends on I2C

sound/soc/codecs/Makefile

@@ -34,6 +34,7 @@ snd-soc-ak4641-objs := ak4641.o
 snd-soc-ak4642-objs := ak4642.o
 snd-soc-ak4671-objs := ak4671.o
 snd-soc-ak5386-objs := ak5386.o
+snd-soc-ak5558-objs := ak5558.o
 snd-soc-arizona-objs := arizona.o
 snd-soc-bt-sco-objs := bt-sco.o
 snd-soc-cq93vc-objs := cq93vc.o
@@ -277,6 +278,7 @@ obj-$(CONFIG_SND_SOC_AK4641)	+= snd-soc-ak4641.o
 obj-$(CONFIG_SND_SOC_AK4642)	+= snd-soc-ak4642.o
 obj-$(CONFIG_SND_SOC_AK4671)	+= snd-soc-ak4671.o
 obj-$(CONFIG_SND_SOC_AK5386)	+= snd-soc-ak5386.o
+obj-$(CONFIG_SND_SOC_AK5558)	+= snd-soc-ak5558.o
 obj-$(CONFIG_SND_SOC_ALC5623)    += snd-soc-alc5623.o
 obj-$(CONFIG_SND_SOC_ALC5632)	+= snd-soc-alc5632.o
 obj-$(CONFIG_SND_SOC_ARIZONA)	+= snd-soc-arizona.o

sound/soc/codecs/ak5558.h

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Audio driver header for AK5558
+ *
+ * Copyright (C) 2016 Asahi Kasei Microdevices Corporation
+ * Copyright 2018 NXP
+ */
+
+#ifndef _AK5558_H
+#define _AK5558_H
+
+#define AK5558_00_POWER_MANAGEMENT1    0x00
+#define AK5558_01_POWER_MANAGEMENT2    0x01
+#define AK5558_02_CONTROL1             0x02
+#define AK5558_03_CONTROL2             0x03
+#define AK5558_04_CONTROL3             0x04
+#define AK5558_05_DSD                  0x05
+
+/* AK5558_02_CONTROL1 fields */
+#define AK5558_DIF			GENMASK(1, 1)
+#define AK5558_DIF_MSB_MODE		(0 << 1)
+#define AK5558_DIF_I2S_MODE		(1 << 1)
+
+#define AK5558_BITS			GENMASK(2, 2)
+#define AK5558_DIF_24BIT_MODE		(0 << 2)
+#define AK5558_DIF_32BIT_MODE		(1 << 2)
+
+#define AK5558_CKS			GENMASK(6, 3)
+#define AK5558_CKS_128FS_192KHZ		(0 << 3)
+#define AK5558_CKS_192FS_192KHZ		(1 << 3)
+#define AK5558_CKS_256FS_48KHZ		(2 << 3)
+#define AK5558_CKS_256FS_96KHZ		(3 << 3)
+#define AK5558_CKS_384FS_96KHZ		(4 << 3)
+#define AK5558_CKS_384FS_48KHZ		(5 << 3)
+#define AK5558_CKS_512FS_48KHZ		(6 << 3)
+#define AK5558_CKS_768FS_48KHZ		(7 << 3)
+#define AK5558_CKS_64FS_384KHZ		(8 << 3)
+#define AK5558_CKS_32FS_768KHZ		(9 << 3)
+#define AK5558_CKS_96FS_384KHZ		(10 << 3)
+#define AK5558_CKS_48FS_768KHZ		(11 << 3)
+#define AK5558_CKS_64FS_768KHZ		(12 << 3)
+#define AK5558_CKS_1024FS_16KHZ		(13 << 3)
+#define AK5558_CKS_AUTO			(15 << 3)
+
+/* AK5558_03_CONTROL2 fields */
+#define AK5558_MODE_BITS	GENMASK(6, 5)
+#define AK5558_MODE_NORMAL	(0 << 5)
+#define AK5558_MODE_TDM128	(1 << 5)
+#define AK5558_MODE_TDM256	(2 << 5)
+#define AK5558_MODE_TDM512	(3 << 5)
+
+#endif