sound/soc/codecs/tpa6130a2.c - maze/linux - Git at Google

 /*
  * ALSA SoC Texas Instruments TPA6130A2 headset stereo amplifier driver
  *
  * Copyright (C) Nokia Corporation
  *
  * Author: Peter Ujfalusi <peter.ujfalusi@nokia.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * version 2 as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  * 02110-1301 USA
  */

 #include <linux/module.h>
 #include <linux/errno.h>
 #include <linux/device.h>
 #include <linux/i2c.h>
 #include <linux/gpio.h>
 #include <linux/regulator/consumer.h>
 #include <sound/tpa6130a2-plat.h>
 #include <sound/soc.h>
 #include <sound/soc-dapm.h>
 #include <sound/tlv.h>

 #include "tpa6130a2.h"

 static struct i2c_client *tpa6130a2_client;

 #define TPA6130A2_NUM_SUPPLIES 2
 static const char *tpa6130a2_supply_names[TPA6130A2_NUM_SUPPLIES] = {
 	"CPVSS",
 	"Vdd",
 };

 /* This struct is used to save the context */
 struct tpa6130a2_data {
 	struct mutex mutex;
 	unsigned char regs[TPA6130A2_CACHEREGNUM];
 	struct regulator_bulk_data supplies[TPA6130A2_NUM_SUPPLIES];
 	int power_gpio;
 	unsigned char power_state;
 };

 static int tpa6130a2_i2c_read(int reg)
 {
 	struct tpa6130a2_data *data;
 	int val;

 	BUG_ON(tpa6130a2_client == NULL);
 	data = i2c_get_clientdata(tpa6130a2_client);

 	/* If powered off, return the cached value */
 	if (data->power_state) {
 		val = i2c_smbus_read_byte_data(tpa6130a2_client, reg);
 		if (val < 0)
 			dev_err(&tpa6130a2_client->dev, "Read failed\n");
 		else
 			data->regs[reg] = val;
 	} else {
 		val = data->regs[reg];
 	}

 	return val;
 }

 static int tpa6130a2_i2c_write(int reg, u8 value)
 {
 	struct tpa6130a2_data *data;
 	int val = 0;

 	BUG_ON(tpa6130a2_client == NULL);
 	data = i2c_get_clientdata(tpa6130a2_client);

 	if (data->power_state) {
 		val = i2c_smbus_write_byte_data(tpa6130a2_client, reg, value);
 		if (val < 0)
 			dev_err(&tpa6130a2_client->dev, "Write failed\n");
 	}

 	/* Either powered on or off, we save the context */
 	data->regs[reg] = value;

 	return val;
 }

 static u8 tpa6130a2_read(int reg)
 {
 	struct tpa6130a2_data *data;

 	BUG_ON(tpa6130a2_client == NULL);
 	data = i2c_get_clientdata(tpa6130a2_client);

 	return data->regs[reg];
 }

 static void tpa6130a2_initialize(void)
 {
 	struct tpa6130a2_data *data;
 	int i;

 	BUG_ON(tpa6130a2_client == NULL);
 	data = i2c_get_clientdata(tpa6130a2_client);

 	for (i = 1; i < TPA6130A2_REG_VERSION; i++)
 		tpa6130a2_i2c_write(i, data->regs[i]);
 }

 static int tpa6130a2_power(int power)
 {
 	struct	tpa6130a2_data *data;
 	u8	val;
 	int	ret;

 	BUG_ON(tpa6130a2_client == NULL);
 	data = i2c_get_clientdata(tpa6130a2_client);

 	mutex_lock(&data->mutex);
 	if (power) {
 		/* Power on */
 		if (data->power_gpio >= 0)
 			gpio_set_value(data->power_gpio, 1);

 		ret = regulator_bulk_enable(ARRAY_SIZE(data->supplies),
 					    data->supplies);
 		if (ret != 0) {
 			dev_err(&tpa6130a2_client->dev,
 				"Failed to enable supplies: %d\n", ret);
 			goto exit;
 		}

 		data->power_state = 1;
 		tpa6130a2_initialize();

 		/* Clear SWS */
 		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
 		val &= ~TPA6130A2_SWS;
 		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
 	} else {
 		/* set SWS */
 		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
 		val |= TPA6130A2_SWS;
 		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);

 		/* Power off */
 		if (data->power_gpio >= 0)
 			gpio_set_value(data->power_gpio, 0);

 		ret = regulator_bulk_disable(ARRAY_SIZE(data->supplies),
 					     data->supplies);
 		if (ret != 0) {
 			dev_err(&tpa6130a2_client->dev,
 				"Failed to disable supplies: %d\n", ret);
 			goto exit;
 		}

 		data->power_state = 0;
 	}

 exit:
 	mutex_unlock(&data->mutex);
 	return ret;
 }

 static int tpa6130a2_get_reg(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct soc_mixer_control *mc =
 		(struct soc_mixer_control *)kcontrol->private_value;
 	struct tpa6130a2_data *data;
 	unsigned int reg = mc->reg;
 	unsigned int shift = mc->shift;
 	unsigned int mask = mc->max;
 	unsigned int invert = mc->invert;

 	BUG_ON(tpa6130a2_client == NULL);
 	data = i2c_get_clientdata(tpa6130a2_client);

 	mutex_lock(&data->mutex);

 	ucontrol->value.integer.value[0] =
 		(tpa6130a2_read(reg) >> shift) & mask;

 	if (invert)
 		ucontrol->value.integer.value[0] =
 			mask - ucontrol->value.integer.value[0];

 	mutex_unlock(&data->mutex);
 	return 0;
 }

 static int tpa6130a2_set_reg(struct snd_kcontrol *kcontrol,
 		struct snd_ctl_elem_value *ucontrol)
 {
 	struct soc_mixer_control *mc =
 		(struct soc_mixer_control *)kcontrol->private_value;
 	struct tpa6130a2_data *data;
 	unsigned int reg = mc->reg;
 	unsigned int shift = mc->shift;
 	unsigned int mask = mc->max;
 	unsigned int invert = mc->invert;
 	unsigned int val = (ucontrol->value.integer.value[0] & mask);
 	unsigned int val_reg;

 	BUG_ON(tpa6130a2_client == NULL);
 	data = i2c_get_clientdata(tpa6130a2_client);

 	if (invert)
 		val = mask - val;

 	mutex_lock(&data->mutex);

 	val_reg = tpa6130a2_read(reg);
 	if (((val_reg >> shift) & mask) == val) {
 		mutex_unlock(&data->mutex);
 		return 0;
 	}

 	val_reg &= ~(mask << shift);
 	val_reg |= val << shift;
 	tpa6130a2_i2c_write(reg, val_reg);

 	mutex_unlock(&data->mutex);

 	return 1;
 }

 /*
  * TPA6130 volume. From -59.5 to 4 dB with increasing step size when going
  * down in gain.
  */
 static const unsigned int tpa6130_tlv[] = {
 	TLV_DB_RANGE_HEAD(10),
 	0, 1, TLV_DB_SCALE_ITEM(-5950, 600, 0),
 	2, 3, TLV_DB_SCALE_ITEM(-5000, 250, 0),
 	4, 5, TLV_DB_SCALE_ITEM(-4550, 160, 0),
 	6, 7, TLV_DB_SCALE_ITEM(-4140, 190, 0),
 	8, 9, TLV_DB_SCALE_ITEM(-3650, 120, 0),
 	10, 11, TLV_DB_SCALE_ITEM(-3330, 160, 0),
 	12, 13, TLV_DB_SCALE_ITEM(-3040, 180, 0),
 	14, 20, TLV_DB_SCALE_ITEM(-2710, 110, 0),
 	21, 37, TLV_DB_SCALE_ITEM(-1960, 74, 0),
 	38, 63, TLV_DB_SCALE_ITEM(-720, 45, 0),
 };

 static const struct snd_kcontrol_new tpa6130a2_controls[] = {
 	SOC_SINGLE_EXT_TLV("TPA6130A2 Headphone Playback Volume",
 		       TPA6130A2_REG_VOL_MUTE, 0, 0x3f, 0,
 		       tpa6130a2_get_reg, tpa6130a2_set_reg,
 		       tpa6130_tlv),
 };

 /*
  * Enable or disable channel (left or right)
  * The bit number for mute and amplifier are the same per channel:
  * bit 6: Right channel
  * bit 7: Left channel
  * in both registers.
  */
 static void tpa6130a2_channel_enable(u8 channel, int enable)
 {
 	u8	val;

 	if (enable) {
 		/* Enable channel */
 		/* Enable amplifier */
 		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
 		val |= channel;
 		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);

 		/* Unmute channel */
 		val = tpa6130a2_read(TPA6130A2_REG_VOL_MUTE);
 		val &= ~channel;
 		tpa6130a2_i2c_write(TPA6130A2_REG_VOL_MUTE, val);
 	} else {
 		/* Disable channel */
 		/* Mute channel */
 		val = tpa6130a2_read(TPA6130A2_REG_VOL_MUTE);
 		val |= channel;
 		tpa6130a2_i2c_write(TPA6130A2_REG_VOL_MUTE, val);

 		/* Disable amplifier */
 		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
 		val &= ~channel;
 		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
 	}
 }

 static int tpa6130a2_left_event(struct snd_soc_dapm_widget *w,
 		struct snd_kcontrol *kcontrol, int event)
 {
 	switch (event) {
 	case SND_SOC_DAPM_POST_PMU:
 		tpa6130a2_channel_enable(TPA6130A2_HP_EN_L, 1);
 		break;
 	case SND_SOC_DAPM_POST_PMD:
 		tpa6130a2_channel_enable(TPA6130A2_HP_EN_L, 0);
 		break;
 	}
 	return 0;
 }

 static int tpa6130a2_right_event(struct snd_soc_dapm_widget *w,
 		struct snd_kcontrol *kcontrol, int event)
 {
 	switch (event) {
 	case SND_SOC_DAPM_POST_PMU:
 		tpa6130a2_channel_enable(TPA6130A2_HP_EN_R, 1);
 		break;
 	case SND_SOC_DAPM_POST_PMD:
 		tpa6130a2_channel_enable(TPA6130A2_HP_EN_R, 0);
 		break;
 	}
 	return 0;
 }

 static int tpa6130a2_supply_event(struct snd_soc_dapm_widget *w,
 		struct snd_kcontrol *kcontrol, int event)
 {
 	int ret = 0;

 	switch (event) {
 	case SND_SOC_DAPM_POST_PMU:
 		ret = tpa6130a2_power(1);
 		break;
 	case SND_SOC_DAPM_POST_PMD:
 		ret = tpa6130a2_power(0);
 		break;
 	}
 	return ret;
 }

 static const struct snd_soc_dapm_widget tpa6130a2_dapm_widgets[] = {
 	SND_SOC_DAPM_PGA_E("TPA6130A2 Left", SND_SOC_NOPM,
 			0, 0, NULL, 0, tpa6130a2_left_event,
 			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
 	SND_SOC_DAPM_PGA_E("TPA6130A2 Right", SND_SOC_NOPM,
 			0, 0, NULL, 0, tpa6130a2_right_event,
 			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
 	SND_SOC_DAPM_SUPPLY("TPA6130A2 Enable", SND_SOC_NOPM,
 			0, 0, tpa6130a2_supply_event,
 			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
 	/* Outputs */
 	SND_SOC_DAPM_HP("TPA6130A2 Headphone Left", NULL),
 	SND_SOC_DAPM_HP("TPA6130A2 Headphone Right", NULL),
 };

 static const struct snd_soc_dapm_route audio_map[] = {
 	{"TPA6130A2 Headphone Left", NULL, "TPA6130A2 Left"},
 	{"TPA6130A2 Headphone Right", NULL, "TPA6130A2 Right"},

 	{"TPA6130A2 Headphone Left", NULL, "TPA6130A2 Enable"},
 	{"TPA6130A2 Headphone Right", NULL, "TPA6130A2 Enable"},
 };

 int tpa6130a2_add_controls(struct snd_soc_codec *codec)
 {
 	snd_soc_dapm_new_controls(codec, tpa6130a2_dapm_widgets,
 				ARRAY_SIZE(tpa6130a2_dapm_widgets));

 	snd_soc_dapm_add_routes(codec, audio_map, ARRAY_SIZE(audio_map));

 	return snd_soc_add_controls(codec, tpa6130a2_controls,
 				ARRAY_SIZE(tpa6130a2_controls));

 }
 EXPORT_SYMBOL_GPL(tpa6130a2_add_controls);

 static int tpa6130a2_probe(struct i2c_client *client,
 			   const struct i2c_device_id *id)
 {
 	struct device *dev;
 	struct tpa6130a2_data *data;
 	struct tpa6130a2_platform_data *pdata;
 	int i, ret;

 	dev = &client->dev;

 	if (client->dev.platform_data == NULL) {
 		dev_err(dev, "Platform data not set\n");
 		dump_stack();
 		return -ENODEV;
 	}

 	data = kzalloc(sizeof(*data), GFP_KERNEL);
 	if (data == NULL) {
 		dev_err(dev, "Can not allocate memory\n");
 		return -ENOMEM;
 	}

 	tpa6130a2_client = client;

 	i2c_set_clientdata(tpa6130a2_client, data);

 	pdata = client->dev.platform_data;
 	data->power_gpio = pdata->power_gpio;

 	mutex_init(&data->mutex);

 	/* Set default register values */
 	data->regs[TPA6130A2_REG_CONTROL] =	TPA6130A2_SWS;
 	data->regs[TPA6130A2_REG_VOL_MUTE] =	TPA6130A2_MUTE_R |
 						TPA6130A2_MUTE_L;

 	if (data->power_gpio >= 0) {
 		ret = gpio_request(data->power_gpio, "tpa6130a2 enable");
 		if (ret < 0) {
 			dev_err(dev, "Failed to request power GPIO (%d)\n",
 				data->power_gpio);
 			goto err_gpio;
 		}
 		gpio_direction_output(data->power_gpio, 0);
 	}

 	for (i = 0; i < ARRAY_SIZE(data->supplies); i++)
 		data->supplies[i].supply = tpa6130a2_supply_names[i];

 	ret = regulator_bulk_get(dev, ARRAY_SIZE(data->supplies),
 				 data->supplies);
 	if (ret != 0) {
 		dev_err(dev, "Failed to request supplies: %d\n", ret);
 		goto err_regulator;
 	}

 	ret = tpa6130a2_power(1);
 	if (ret != 0)
 		goto err_power;


 	/* Read version */
 	ret = tpa6130a2_i2c_read(TPA6130A2_REG_VERSION) &
 				 TPA6130A2_VERSION_MASK;
 	if ((ret != 1) && (ret != 2))
 		dev_warn(dev, "UNTESTED version detected (%d)\n", ret);

 	/* Disable the chip */
 	ret = tpa6130a2_power(0);
 	if (ret != 0)
 		goto err_power;

 	return 0;

 err_power:
 	regulator_bulk_free(ARRAY_SIZE(data->supplies), data->supplies);
 err_regulator:
 	if (data->power_gpio >= 0)
 		gpio_free(data->power_gpio);
 err_gpio:
 	kfree(data);
 	i2c_set_clientdata(tpa6130a2_client, NULL);
 	tpa6130a2_client = NULL;

 	return ret;
 }

 static int tpa6130a2_remove(struct i2c_client *client)
 {
 	struct tpa6130a2_data *data = i2c_get_clientdata(client);

 	tpa6130a2_power(0);

 	if (data->power_gpio >= 0)
 		gpio_free(data->power_gpio);

 	regulator_bulk_free(ARRAY_SIZE(data->supplies), data->supplies);

 	kfree(data);
 	tpa6130a2_client = NULL;

 	return 0;
 }

 static const struct i2c_device_id tpa6130a2_id[] = {
 	{ "tpa6130a2", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, tpa6130a2_id);

 static struct i2c_driver tpa6130a2_i2c_driver = {
 	.driver = {
 		.name = "tpa6130a2",
 		.owner = THIS_MODULE,
 	},
 	.probe = tpa6130a2_probe,
 	.remove = __devexit_p(tpa6130a2_remove),
 	.id_table = tpa6130a2_id,
 };

 static int __init tpa6130a2_init(void)
 {
 	return i2c_add_driver(&tpa6130a2_i2c_driver);
 }

 static void __exit tpa6130a2_exit(void)
 {
 	i2c_del_driver(&tpa6130a2_i2c_driver);
 }

 MODULE_AUTHOR("Peter Ujfalusi");
 MODULE_DESCRIPTION("TPA6130A2 Headphone amplifier driver");
 MODULE_LICENSE("GPL");

 module_init(tpa6130a2_init);
 module_exit(tpa6130a2_exit);
	/*
	* ALSA SoC Texas Instruments TPA6130A2 headset stereo amplifier driver
	*
	* Copyright (C) Nokia Corporation
	*
	* Author: Peter Ujfalusi <peter.ujfalusi@nokia.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* version 2 as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
	* 02110-1301 USA
	*/

	#include <linux/module.h>
	#include <linux/errno.h>
	#include <linux/device.h>
	#include <linux/i2c.h>
	#include <linux/gpio.h>
	#include <linux/regulator/consumer.h>
	#include <sound/tpa6130a2-plat.h>
	#include <sound/soc.h>
	#include <sound/soc-dapm.h>
	#include <sound/tlv.h>

	#include "tpa6130a2.h"

	static struct i2c_client *tpa6130a2_client;

	#define TPA6130A2_NUM_SUPPLIES 2
	static const char *tpa6130a2_supply_names[TPA6130A2_NUM_SUPPLIES] = {
	"CPVSS",
	"Vdd",
	};

	/* This struct is used to save the context */
	struct tpa6130a2_data {
	struct mutex mutex;
	unsigned char regs[TPA6130A2_CACHEREGNUM];
	struct regulator_bulk_data supplies[TPA6130A2_NUM_SUPPLIES];
	int power_gpio;
	unsigned char power_state;
	};

	static int tpa6130a2_i2c_read(int reg)
	{
	struct tpa6130a2_data *data;
	int val;

	BUG_ON(tpa6130a2_client == NULL);
	data = i2c_get_clientdata(tpa6130a2_client);

	/* If powered off, return the cached value */
	if (data->power_state) {
	val = i2c_smbus_read_byte_data(tpa6130a2_client, reg);
	if (val < 0)
	dev_err(&tpa6130a2_client->dev, "Read failed\n");
	else
	data->regs[reg] = val;
	} else {
	val = data->regs[reg];
	}

	return val;
	}

	static int tpa6130a2_i2c_write(int reg, u8 value)
	{
	struct tpa6130a2_data *data;
	int val = 0;

	BUG_ON(tpa6130a2_client == NULL);
	data = i2c_get_clientdata(tpa6130a2_client);

	if (data->power_state) {
	val = i2c_smbus_write_byte_data(tpa6130a2_client, reg, value);
	if (val < 0)
	dev_err(&tpa6130a2_client->dev, "Write failed\n");
	}

	/* Either powered on or off, we save the context */
	data->regs[reg] = value;

	return val;
	}

	static u8 tpa6130a2_read(int reg)
	{
	struct tpa6130a2_data *data;

	BUG_ON(tpa6130a2_client == NULL);
	data = i2c_get_clientdata(tpa6130a2_client);

	return data->regs[reg];
	}

	static void tpa6130a2_initialize(void)
	{
	struct tpa6130a2_data *data;
	int i;

	BUG_ON(tpa6130a2_client == NULL);
	data = i2c_get_clientdata(tpa6130a2_client);

	for (i = 1; i < TPA6130A2_REG_VERSION; i++)
	tpa6130a2_i2c_write(i, data->regs[i]);
	}

	static int tpa6130a2_power(int power)
	{
	struct tpa6130a2_data *data;
	u8 val;
	int ret;

	BUG_ON(tpa6130a2_client == NULL);
	data = i2c_get_clientdata(tpa6130a2_client);

	mutex_lock(&data->mutex);
	if (power) {
	/* Power on */
	if (data->power_gpio >= 0)
	gpio_set_value(data->power_gpio, 1);

	ret = regulator_bulk_enable(ARRAY_SIZE(data->supplies),
	data->supplies);
	if (ret != 0) {
	dev_err(&tpa6130a2_client->dev,
	"Failed to enable supplies: %d\n", ret);
	goto exit;
	}

	data->power_state = 1;
	tpa6130a2_initialize();

	/* Clear SWS */
	val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
	val &= ~TPA6130A2_SWS;
	tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
	} else {
	/* set SWS */
	val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
	val \|= TPA6130A2_SWS;
	tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);

	/* Power off */
	if (data->power_gpio >= 0)
	gpio_set_value(data->power_gpio, 0);

	ret = regulator_bulk_disable(ARRAY_SIZE(data->supplies),
	data->supplies);
	if (ret != 0) {
	dev_err(&tpa6130a2_client->dev,
	"Failed to disable supplies: %d\n", ret);
	goto exit;
	}

	data->power_state = 0;
	}

	exit:
	mutex_unlock(&data->mutex);
	return ret;
	}

	static int tpa6130a2_get_reg(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct soc_mixer_control *mc =
	(struct soc_mixer_control *)kcontrol->private_value;
	struct tpa6130a2_data *data;
	unsigned int reg = mc->reg;
	unsigned int shift = mc->shift;
	unsigned int mask = mc->max;
	unsigned int invert = mc->invert;

	BUG_ON(tpa6130a2_client == NULL);
	data = i2c_get_clientdata(tpa6130a2_client);

	mutex_lock(&data->mutex);

	ucontrol->value.integer.value[0] =
	(tpa6130a2_read(reg) >> shift) & mask;

	if (invert)
	ucontrol->value.integer.value[0] =
	mask - ucontrol->value.integer.value[0];

	mutex_unlock(&data->mutex);
	return 0;
	}

	static int tpa6130a2_set_reg(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct soc_mixer_control *mc =
	(struct soc_mixer_control *)kcontrol->private_value;
	struct tpa6130a2_data *data;
	unsigned int reg = mc->reg;
	unsigned int shift = mc->shift;
	unsigned int mask = mc->max;
	unsigned int invert = mc->invert;
	unsigned int val = (ucontrol->value.integer.value[0] & mask);
	unsigned int val_reg;

	BUG_ON(tpa6130a2_client == NULL);
	data = i2c_get_clientdata(tpa6130a2_client);

	if (invert)
	val = mask - val;

	mutex_lock(&data->mutex);

	val_reg = tpa6130a2_read(reg);
	if (((val_reg >> shift) & mask) == val) {
	mutex_unlock(&data->mutex);
	return 0;
	}

	val_reg &= ~(mask << shift);
	val_reg \|= val << shift;
	tpa6130a2_i2c_write(reg, val_reg);

	mutex_unlock(&data->mutex);

	return 1;
	}

	/*
	* TPA6130 volume. From -59.5 to 4 dB with increasing step size when going
	* down in gain.
	*/
	static const unsigned int tpa6130_tlv[] = {
	TLV_DB_RANGE_HEAD(10),
	0, 1, TLV_DB_SCALE_ITEM(-5950, 600, 0),
	2, 3, TLV_DB_SCALE_ITEM(-5000, 250, 0),
	4, 5, TLV_DB_SCALE_ITEM(-4550, 160, 0),
	6, 7, TLV_DB_SCALE_ITEM(-4140, 190, 0),
	8, 9, TLV_DB_SCALE_ITEM(-3650, 120, 0),
	10, 11, TLV_DB_SCALE_ITEM(-3330, 160, 0),
	12, 13, TLV_DB_SCALE_ITEM(-3040, 180, 0),
	14, 20, TLV_DB_SCALE_ITEM(-2710, 110, 0),
	21, 37, TLV_DB_SCALE_ITEM(-1960, 74, 0),
	38, 63, TLV_DB_SCALE_ITEM(-720, 45, 0),
	};

	static const struct snd_kcontrol_new tpa6130a2_controls[] = {
	SOC_SINGLE_EXT_TLV("TPA6130A2 Headphone Playback Volume",
	TPA6130A2_REG_VOL_MUTE, 0, 0x3f, 0,
	tpa6130a2_get_reg, tpa6130a2_set_reg,
	tpa6130_tlv),
	};

	/*
	* Enable or disable channel (left or right)
	* The bit number for mute and amplifier are the same per channel:
	* bit 6: Right channel
	* bit 7: Left channel
	* in both registers.
	*/
	static void tpa6130a2_channel_enable(u8 channel, int enable)
	{
	u8 val;

	if (enable) {
	/* Enable channel */
	/* Enable amplifier */
	val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
	val \|= channel;
	tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);

	/* Unmute channel */
	val = tpa6130a2_read(TPA6130A2_REG_VOL_MUTE);
	val &= ~channel;
	tpa6130a2_i2c_write(TPA6130A2_REG_VOL_MUTE, val);
	} else {
	/* Disable channel */
	/* Mute channel */
	val = tpa6130a2_read(TPA6130A2_REG_VOL_MUTE);
	val \|= channel;
	tpa6130a2_i2c_write(TPA6130A2_REG_VOL_MUTE, val);

	/* Disable amplifier */
	val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
	val &= ~channel;
	tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
	}
	}

	static int tpa6130a2_left_event(struct snd_soc_dapm_widget *w,
	struct snd_kcontrol *kcontrol, int event)
	{
	switch (event) {
	case SND_SOC_DAPM_POST_PMU:
	tpa6130a2_channel_enable(TPA6130A2_HP_EN_L, 1);
	break;
	case SND_SOC_DAPM_POST_PMD:
	tpa6130a2_channel_enable(TPA6130A2_HP_EN_L, 0);
	break;
	}
	return 0;
	}

	static int tpa6130a2_right_event(struct snd_soc_dapm_widget *w,
	struct snd_kcontrol *kcontrol, int event)
	{
	switch (event) {
	case SND_SOC_DAPM_POST_PMU:
	tpa6130a2_channel_enable(TPA6130A2_HP_EN_R, 1);
	break;
	case SND_SOC_DAPM_POST_PMD:
	tpa6130a2_channel_enable(TPA6130A2_HP_EN_R, 0);
	break;
	}
	return 0;
	}

	static int tpa6130a2_supply_event(struct snd_soc_dapm_widget *w,
	struct snd_kcontrol *kcontrol, int event)
	{
	int ret = 0;

	switch (event) {
	case SND_SOC_DAPM_POST_PMU:
	ret = tpa6130a2_power(1);
	break;
	case SND_SOC_DAPM_POST_PMD:
	ret = tpa6130a2_power(0);
	break;
	}
	return ret;
	}

	static const struct snd_soc_dapm_widget tpa6130a2_dapm_widgets[] = {
	SND_SOC_DAPM_PGA_E("TPA6130A2 Left", SND_SOC_NOPM,
	0, 0, NULL, 0, tpa6130a2_left_event,
	SND_SOC_DAPM_POST_PMU\|SND_SOC_DAPM_POST_PMD),
	SND_SOC_DAPM_PGA_E("TPA6130A2 Right", SND_SOC_NOPM,
	0, 0, NULL, 0, tpa6130a2_right_event,
	SND_SOC_DAPM_POST_PMU\|SND_SOC_DAPM_POST_PMD),
	SND_SOC_DAPM_SUPPLY("TPA6130A2 Enable", SND_SOC_NOPM,
	0, 0, tpa6130a2_supply_event,
	SND_SOC_DAPM_POST_PMU\|SND_SOC_DAPM_POST_PMD),
	/* Outputs */
	SND_SOC_DAPM_HP("TPA6130A2 Headphone Left", NULL),
	SND_SOC_DAPM_HP("TPA6130A2 Headphone Right", NULL),
	};

	static const struct snd_soc_dapm_route audio_map[] = {
	{"TPA6130A2 Headphone Left", NULL, "TPA6130A2 Left"},
	{"TPA6130A2 Headphone Right", NULL, "TPA6130A2 Right"},

	{"TPA6130A2 Headphone Left", NULL, "TPA6130A2 Enable"},
	{"TPA6130A2 Headphone Right", NULL, "TPA6130A2 Enable"},
	};

	int tpa6130a2_add_controls(struct snd_soc_codec *codec)
	{
	snd_soc_dapm_new_controls(codec, tpa6130a2_dapm_widgets,
	ARRAY_SIZE(tpa6130a2_dapm_widgets));

	snd_soc_dapm_add_routes(codec, audio_map, ARRAY_SIZE(audio_map));

	return snd_soc_add_controls(codec, tpa6130a2_controls,
	ARRAY_SIZE(tpa6130a2_controls));

	}
	EXPORT_SYMBOL_GPL(tpa6130a2_add_controls);

	static int tpa6130a2_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct device *dev;
	struct tpa6130a2_data *data;
	struct tpa6130a2_platform_data *pdata;
	int i, ret;

	dev = &client->dev;

	if (client->dev.platform_data == NULL) {
	dev_err(dev, "Platform data not set\n");
	dump_stack();
	return -ENODEV;
	}

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (data == NULL) {
	dev_err(dev, "Can not allocate memory\n");
	return -ENOMEM;
	}

	tpa6130a2_client = client;

	i2c_set_clientdata(tpa6130a2_client, data);

	pdata = client->dev.platform_data;
	data->power_gpio = pdata->power_gpio;

	mutex_init(&data->mutex);

	/* Set default register values */
	data->regs[TPA6130A2_REG_CONTROL] = TPA6130A2_SWS;
	data->regs[TPA6130A2_REG_VOL_MUTE] = TPA6130A2_MUTE_R \|
	TPA6130A2_MUTE_L;

	if (data->power_gpio >= 0) {
	ret = gpio_request(data->power_gpio, "tpa6130a2 enable");
	if (ret < 0) {
	dev_err(dev, "Failed to request power GPIO (%d)\n",
	data->power_gpio);
	goto err_gpio;
	}
	gpio_direction_output(data->power_gpio, 0);
	}

	for (i = 0; i < ARRAY_SIZE(data->supplies); i++)
	data->supplies[i].supply = tpa6130a2_supply_names[i];

	ret = regulator_bulk_get(dev, ARRAY_SIZE(data->supplies),
	data->supplies);
	if (ret != 0) {
	dev_err(dev, "Failed to request supplies: %d\n", ret);
	goto err_regulator;
	}

	ret = tpa6130a2_power(1);
	if (ret != 0)
	goto err_power;


	/* Read version */
	ret = tpa6130a2_i2c_read(TPA6130A2_REG_VERSION) &
	TPA6130A2_VERSION_MASK;
	if ((ret != 1) && (ret != 2))
	dev_warn(dev, "UNTESTED version detected (%d)\n", ret);

	/* Disable the chip */
	ret = tpa6130a2_power(0);
	if (ret != 0)
	goto err_power;

	return 0;

	err_power:
	regulator_bulk_free(ARRAY_SIZE(data->supplies), data->supplies);
	err_regulator:
	if (data->power_gpio >= 0)
	gpio_free(data->power_gpio);
	err_gpio:
	kfree(data);
	i2c_set_clientdata(tpa6130a2_client, NULL);
	tpa6130a2_client = NULL;

	return ret;
	}

	static int tpa6130a2_remove(struct i2c_client *client)
	{
	struct tpa6130a2_data *data = i2c_get_clientdata(client);

	tpa6130a2_power(0);

	if (data->power_gpio >= 0)
	gpio_free(data->power_gpio);

	regulator_bulk_free(ARRAY_SIZE(data->supplies), data->supplies);

	kfree(data);
	tpa6130a2_client = NULL;

	return 0;
	}

	static const struct i2c_device_id tpa6130a2_id[] = {
	{ "tpa6130a2", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, tpa6130a2_id);

	static struct i2c_driver tpa6130a2_i2c_driver = {
	.driver = {
	.name = "tpa6130a2",
	.owner = THIS_MODULE,
	},
	.probe = tpa6130a2_probe,
	.remove = __devexit_p(tpa6130a2_remove),
	.id_table = tpa6130a2_id,
	};

	static int __init tpa6130a2_init(void)
	{
	return i2c_add_driver(&tpa6130a2_i2c_driver);
	}

	static void __exit tpa6130a2_exit(void)
	{
	i2c_del_driver(&tpa6130a2_i2c_driver);
	}

	MODULE_AUTHOR("Peter Ujfalusi");
	MODULE_DESCRIPTION("TPA6130A2 Headphone amplifier driver");
	MODULE_LICENSE("GPL");

	module_init(tpa6130a2_init);
	module_exit(tpa6130a2_exit);