ASoC: MAX9877: add MAX9877 amp driver

The MAX9877 combines a high-efficiency Class D audio power amplifier
with a stereo Class AB capacitor-less DirectDrive headphone amplifier.

The max9877_add_controls() is called to register the MAX9877 specific
controls on machine specific init() of the machine driver.

The datasheet for the MAX9877 can find at the following url:
http://datasheets.maxim-ic.com/en/ds/MAX9877.pdf

[Slight edit to sort the ALL_CODECS entries -- broonie.]

Signed-off-by: Joonyoung Shim <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/codecs/Kconfig

···
 	select SND_SOC_AK4104 if SPI_MASTER
 	select SND_SOC_AK4535 if I2C
 	select SND_SOC_CS4270 if I2C
+	select SND_SOC_MAX9877 if I2C
 	select SND_SOC_PCM3008
 	select SND_SOC_SPDIF
 	select SND_SOC_SSM2602 if I2C
···
 	tristate
 
 config SND_SOC_WM9713
+	tristate
+
+# Amp
+config SND_SOC_MAX9877
 	tristate

sound/soc/codecs/Makefile

···
 snd-soc-wm9712-objs := wm9712.o
 snd-soc-wm9713-objs := wm9713.o
 
+# Amp
+snd-soc-max9877-objs := max9877.o
+
 obj-$(CONFIG_SND_SOC_AC97_CODEC)	+= snd-soc-ac97.o
 obj-$(CONFIG_SND_SOC_AD1980)	+= snd-soc-ad1980.o
 obj-$(CONFIG_SND_SOC_AD73311) += snd-soc-ad73311.o
···
 obj-$(CONFIG_SND_SOC_WM9705)	+= snd-soc-wm9705.o
 obj-$(CONFIG_SND_SOC_WM9712)	+= snd-soc-wm9712.o
 obj-$(CONFIG_SND_SOC_WM9713)	+= snd-soc-wm9713.o
+
+# Amp
+obj-$(CONFIG_SND_SOC_MAX9877)	+= snd-soc-max9877.o

sound/soc/codecs/max9877.c

···
+/*
+ * max9877.c  --  amp driver for max9877
+ *
+ * Copyright (C) 2009 Samsung Electronics Co.Ltd
+ * Author: Joonyoung Shim <[e-mail]>
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <sound/soc.h>
+#include <sound/tlv.h>
+
+#include "max9877.h"
+
+static struct i2c_client *i2c;
+
+static u8 max9877_regs[5] = { 0x40, 0x00, 0x00, 0x00, 0x49 };
+
+static void max9877_write_regs(void)
+{
+	if (i2c_master_send(i2c, max9877_regs, 5) != 5)
+		dev_err(&i2c->dev, "i2c write failed\n");
+}
+
+static int max9877_get_reg(struct snd_kcontrol *kcontrol,
+		struct snd_ctl_elem_value *ucontrol)
+{
+	struct soc_mixer_control *mc =
+		(struct soc_mixer_control *)kcontrol->private_value;
+	int reg = mc->reg;
+	int reg2 = mc->rreg;
+	int shift = mc->shift;
+	int mask = mc->max;
+
+	ucontrol->value.integer.value[0] = (max9877_regs[reg] >> shift) & mask;
+
+	if (reg2)
+		ucontrol->value.integer.value[1] =
+			(max9877_regs[reg2] >> shift) & mask;
+
+	return 0;
+}
+
+static int max9877_set_reg(struct snd_kcontrol *kcontrol,
+		struct snd_ctl_elem_value *ucontrol)
+{
+	struct soc_mixer_control *mc =
+		(struct soc_mixer_control *)kcontrol->private_value;
+	int reg = mc->reg;
+	int reg2 = mc->rreg;
+	int shift = mc->shift;
+	int mask = mc->max;
+	int change = 1;
+	int change2 = 1;
+	int ret = 0;
+
+	if (((max9877_regs[reg] >> shift) & mask) ==
+			ucontrol->value.integer.value[0])
+		change = 0;
+
+	if (reg2)
+		if (((max9877_regs[reg2] >> shift) & mask) ==
+				ucontrol->value.integer.value[1])
+			change2 = 0;
+
+	if (change) {
+		max9877_regs[reg] &= ~(mask << shift);
+		max9877_regs[reg] |= ucontrol->value.integer.value[0] << shift;
+		ret = change;
+	}
+
+	if (reg2 && change2) {
+		max9877_regs[reg2] &= ~(mask << shift);
+		max9877_regs[reg2] |= ucontrol->value.integer.value[1] << shift;
+		ret = change2;
+	}
+
+	if (ret)
+		max9877_write_regs();
+
+	return ret;
+}
+
+static int max9877_get_out_mode(struct snd_kcontrol *kcontrol,
+		struct snd_ctl_elem_value *ucontrol)
+{
+	u8 value = max9877_regs[MAX9877_OUTPUT_MODE] & MAX9877_OUTMODE_MASK;
+
+	if (value)
+		value -= 1;
+
+	ucontrol->value.integer.value[0] = value;
+	return 0;
+}
+
+static int max9877_set_out_mode(struct snd_kcontrol *kcontrol,
+		struct snd_ctl_elem_value *ucontrol)
+{
+	u8 value = ucontrol->value.integer.value[0];
+
+	if (value)
+		value += 1;
+
+	if ((max9877_regs[MAX9877_OUTPUT_MODE] & MAX9877_OUTMODE_MASK) == value)
+		return 0;
+
+	max9877_regs[MAX9877_OUTPUT_MODE] |= value;
+	max9877_write_regs();
+	return 1;
+}
+
+static int max9877_get_osc_mode(struct snd_kcontrol *kcontrol,
+		struct snd_ctl_elem_value *ucontrol)
+{
+	u8 value = (max9877_regs[MAX9877_OUTPUT_MODE] & MAX9877_OSC_MASK);
+
+	value = value >> MAX9877_OSC_OFFSET;
+
+	ucontrol->value.integer.value[0] = value;
+	return 0;
+}
+
+static int max9877_set_osc_mode(struct snd_kcontrol *kcontrol,
+		struct snd_ctl_elem_value *ucontrol)
+{
+	u8 value = ucontrol->value.integer.value[0];
+
+	value = value << MAX9877_OSC_OFFSET;
+	if ((max9877_regs[MAX9877_OUTPUT_MODE] & MAX9877_OSC_MASK) == value)
+		return 0;
+
+	max9877_regs[MAX9877_OUTPUT_MODE] |= value;
+	max9877_write_regs();
+	return 1;
+}
+
+static const unsigned int max9877_pgain_tlv[] = {
+	TLV_DB_RANGE_HEAD(2),
+	0, 1, TLV_DB_SCALE_ITEM(0, 900, 0),
+	2, 2, TLV_DB_SCALE_ITEM(2000, 0, 0),
+};
+
+static const unsigned int max9877_output_tlv[] = {
+	TLV_DB_RANGE_HEAD(4),
+	0, 7, TLV_DB_SCALE_ITEM(-7900, 400, 1),
+	8, 15, TLV_DB_SCALE_ITEM(-4700, 300, 0),
+	16, 23, TLV_DB_SCALE_ITEM(-2300, 200, 0),
+	24, 31, TLV_DB_SCALE_ITEM(-700, 100, 0),
+};
+
+static const char *max9877_out_mode[] = {
+	"INA -> SPK",
+	"INA -> HP",
+	"INA -> SPK and HP",
+	"INB -> SPK",
+	"INB -> HP",
+	"INB -> SPK and HP",
+	"INA + INB -> SPK",
+	"INA + INB -> HP",
+	"INA + INB -> SPK and HP",
+};
+
+static const char *max9877_osc_mode[] = {
+	"1176KHz",
+	"1100KHz",
+	"700KHz",
+};
+
+static const struct soc_enum max9877_enum[] = {
+	SOC_ENUM_SINGLE_EXT(ARRAY_SIZE(max9877_out_mode), max9877_out_mode),
+	SOC_ENUM_SINGLE_EXT(ARRAY_SIZE(max9877_osc_mode), max9877_osc_mode),
+};
+
+static const struct snd_kcontrol_new max9877_controls[] = {
+	SOC_SINGLE_EXT_TLV("MAX9877 PGAINA Playback Volume",
+			MAX9877_INPUT_MODE, 0, 2, 0,
+			max9877_get_reg, max9877_set_reg, max9877_pgain_tlv),
+	SOC_SINGLE_EXT_TLV("MAX9877 PGAINB Playback Volume",
+			MAX9877_INPUT_MODE, 2, 2, 0,
+			max9877_get_reg, max9877_set_reg, max9877_pgain_tlv),
+	SOC_SINGLE_EXT_TLV("MAX9877 Amp Speaker Playback Volume",
+			MAX9877_SPK_VOLUME, 0, 31, 0,
+			max9877_get_reg, max9877_set_reg, max9877_output_tlv),
+	SOC_DOUBLE_R_EXT_TLV("MAX9877 Amp HP Playback Volume",
+			MAX9877_HPL_VOLUME, MAX9877_HPR_VOLUME, 0, 31, 0,
+			max9877_get_reg, max9877_set_reg, max9877_output_tlv),
+	SOC_SINGLE_EXT("MAX9877 INB Stereo Switch",
+			MAX9877_INPUT_MODE, 4, 1, 1,
+			max9877_get_reg, max9877_set_reg),
+	SOC_SINGLE_EXT("MAX9877 INA Stereo Switch",
+			MAX9877_INPUT_MODE, 5, 1, 1,
+			max9877_get_reg, max9877_set_reg),
+	SOC_SINGLE_EXT("MAX9877 Zero-crossing detection Switch",
+			MAX9877_INPUT_MODE, 6, 1, 0,
+			max9877_get_reg, max9877_set_reg),
+	SOC_SINGLE_EXT("MAX9877 Bypass Mode Switch",
+			MAX9877_OUTPUT_MODE, 6, 1, 0,
+			max9877_get_reg, max9877_set_reg),
+	SOC_SINGLE_EXT("MAX9877 Shutdown Mode Switch",
+			MAX9877_OUTPUT_MODE, 7, 1, 1,
+			max9877_get_reg, max9877_set_reg),
+	SOC_ENUM_EXT("MAX9877 Output Mode", max9877_enum[0],
+			max9877_get_out_mode, max9877_set_out_mode),
+	SOC_ENUM_EXT("MAX9877 Oscillator Mode", max9877_enum[1],
+			max9877_get_osc_mode, max9877_set_osc_mode),
+};
+
+/* This function is called from ASoC machine driver */
+int max9877_add_controls(struct snd_soc_codec *codec)
+{
+	return snd_soc_add_controls(codec, max9877_controls,
+			ARRAY_SIZE(max9877_controls));
+}
+EXPORT_SYMBOL_GPL(max9877_add_controls);
+
+static int __devinit max9877_i2c_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	i2c = client;
+
+	max9877_write_regs();
+
+	return 0;
+}
+
+static __devexit int max9877_i2c_remove(struct i2c_client *client)
+{
+	i2c = NULL;
+
+	return 0;
+}
+
+static const struct i2c_device_id max9877_i2c_id[] = {
+	{ "max9877", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max9877_i2c_id);
+
+static struct i2c_driver max9877_i2c_driver = {
+	.driver = {
+		.name = "max9877",
+		.owner = THIS_MODULE,
+	},
+	.probe = max9877_i2c_probe,
+	.remove = __devexit_p(max9877_i2c_remove),
+	.id_table = max9877_i2c_id,
+};
+
+static int __init max9877_init(void)
+{
+	return i2c_add_driver(&max9877_i2c_driver);
+}
+module_init(max9877_init);
+
+static void __exit max9877_exit(void)
+{
+	i2c_del_driver(&max9877_i2c_driver);
+}
+module_exit(max9877_exit);
+
+MODULE_DESCRIPTION("ASoC MAX9877 amp driver");
+MODULE_AUTHOR("Joonyoung Shim <[e-mail]>");
+MODULE_LICENSE("GPL");

sound/soc/codecs/max9877.h

···
+/*
+ * max9877.h  --  amp driver for max9877
+ *
+ * Copyright (C) 2009 Samsung Electronics Co.Ltd
+ * Author: Joonyoung Shim <[e-mail]>
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#ifndef _MAX9877_H
+#define _MAX9877_H
+
+#define MAX9877_INPUT_MODE		0x00
+#define MAX9877_SPK_VOLUME		0x01
+#define MAX9877_HPL_VOLUME		0x02
+#define MAX9877_HPR_VOLUME		0x03
+#define MAX9877_OUTPUT_MODE		0x04
+
+/* MAX9877_INPUT_MODE */
+#define MAX9877_INB			(1 << 4)
+#define MAX9877_INA			(1 << 5)
+#define MAX9877_ZCD			(1 << 6)
+
+/* MAX9877_OUTPUT_MODE */
+#define MAX9877_OUTMODE_MASK		(15 << 0)
+#define MAX9877_OSC_MASK		(3 << 4)
+#define MAX9877_OSC_OFFSET		4
+#define MAX9877_BYPASS			(1 << 6)
+#define MAX9877_SHDN			(1 << 7)
+
+extern int max9877_add_controls(struct snd_soc_codec *codec);
+
+#endif