sound/soc/codecs/max9850.c - kernel/msm-4.9 - Gitiles

 /*
  * max9850.c  --  codec driver for max9850
  *
  * Copyright (C) 2011 taskit GmbH
  *
  * Author: Christian Glindkamp <christian.glindkamp@taskit.de>
  *
  * Initial development of this code was funded by
  * MICRONIC Computer Systeme GmbH, http://www.mcsberlin.de/
  *
  * 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 <linux/regmap.h>
 #include <linux/slab.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>
 #include <sound/tlv.h>

 #include "max9850.h"

 struct max9850_priv {
 	struct regmap *regmap;
 	unsigned int sysclk;
 };

 /* max9850 register cache */
 static const struct reg_default max9850_reg[] = {
 	{  2, 0x0c },
 	{  3, 0x00 },
 	{  4, 0x00 },
 	{  5, 0x00 },
 	{  6, 0x00 },
 	{  7, 0x00 },
 	{  8, 0x00 },
 	{  9, 0x00 },
 	{ 10, 0x00 },
 };

 /* these registers are not used at the moment but provided for the sake of
  * completeness */
 static bool max9850_volatile_register(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case MAX9850_STATUSA:
 	case MAX9850_STATUSB:
 		return 1;
 	default:
 		return 0;
 	}
 }

 static const struct regmap_config max9850_regmap = {
 	.reg_bits = 8,
 	.val_bits = 8,

 	.max_register = MAX9850_DIGITAL_AUDIO,
 	.volatile_reg = max9850_volatile_register,
 	.cache_type = REGCACHE_RBTREE,
 };

 static const unsigned int max9850_tlv[] = {
 	TLV_DB_RANGE_HEAD(4),
 	0x18, 0x1f, TLV_DB_SCALE_ITEM(-7450, 400, 0),
 	0x20, 0x33, TLV_DB_SCALE_ITEM(-4150, 200, 0),
 	0x34, 0x37, TLV_DB_SCALE_ITEM(-150, 100, 0),
 	0x38, 0x3f, TLV_DB_SCALE_ITEM(250, 50, 0),
 };

 static const struct snd_kcontrol_new max9850_controls[] = {
 SOC_SINGLE_TLV("Headphone Volume", MAX9850_VOLUME, 0, 0x3f, 1, max9850_tlv),
 SOC_SINGLE("Headphone Switch", MAX9850_VOLUME, 7, 1, 1),
 SOC_SINGLE("Mono Switch", MAX9850_GENERAL_PURPOSE, 2, 1, 0),
 };

 static const struct snd_kcontrol_new max9850_mixer_controls[] = {
 	SOC_DAPM_SINGLE("Line In Switch", MAX9850_ENABLE, 1, 1, 0),
 };

 static const struct snd_soc_dapm_widget max9850_dapm_widgets[] = {
 SND_SOC_DAPM_SUPPLY("Charge Pump 1", MAX9850_ENABLE, 4, 0, NULL, 0),
 SND_SOC_DAPM_SUPPLY("Charge Pump 2", MAX9850_ENABLE, 5, 0, NULL, 0),
 SND_SOC_DAPM_SUPPLY("MCLK", MAX9850_ENABLE, 6, 0, NULL, 0),
 SND_SOC_DAPM_SUPPLY("SHDN", MAX9850_ENABLE, 7, 0, NULL, 0),
 SND_SOC_DAPM_MIXER_NAMED_CTL("Output Mixer", MAX9850_ENABLE, 2, 0,
 		&max9850_mixer_controls[0],
 		ARRAY_SIZE(max9850_mixer_controls)),
 SND_SOC_DAPM_PGA("Headphone Output", MAX9850_ENABLE, 3, 0, NULL, 0),
 SND_SOC_DAPM_DAC("DAC", "HiFi Playback", MAX9850_ENABLE, 0, 0),
 SND_SOC_DAPM_OUTPUT("OUTL"),
 SND_SOC_DAPM_OUTPUT("HPL"),
 SND_SOC_DAPM_OUTPUT("OUTR"),
 SND_SOC_DAPM_OUTPUT("HPR"),
 SND_SOC_DAPM_MIXER("Line Input", SND_SOC_NOPM, 0, 0, NULL, 0),
 SND_SOC_DAPM_INPUT("INL"),
 SND_SOC_DAPM_INPUT("INR"),
 };

 static const struct snd_soc_dapm_route max9850_dapm_routes[] = {
 	/* output mixer */
 	{"Output Mixer", NULL, "DAC"},
 	{"Output Mixer", "Line In Switch", "Line Input"},

 	/* outputs */
 	{"Headphone Output", NULL, "Output Mixer"},
 	{"HPL", NULL, "Headphone Output"},
 	{"HPR", NULL, "Headphone Output"},
 	{"OUTL", NULL, "Output Mixer"},
 	{"OUTR", NULL, "Output Mixer"},

 	/* inputs */
 	{"Line Input", NULL, "INL"},
 	{"Line Input", NULL, "INR"},

 	/* supplies */
 	{"Output Mixer", NULL, "Charge Pump 1"},
 	{"Output Mixer", NULL, "Charge Pump 2"},
 	{"Output Mixer", NULL, "SHDN"},
 	{"DAC", NULL, "MCLK"},
 };

 static int max9850_hw_params(struct snd_pcm_substream *substream,
 			     struct snd_pcm_hw_params *params,
 			     struct snd_soc_dai *dai)
 {
 	struct snd_soc_codec *codec = dai->codec;
 	struct max9850_priv *max9850 = snd_soc_codec_get_drvdata(codec);
 	u64 lrclk_div;
 	u8 sf, da;

 	if (!max9850->sysclk)
 		return -EINVAL;

 	/* lrclk_div = 2^22 * rate / iclk with iclk = mclk / sf */
 	sf = (snd_soc_read(codec, MAX9850_CLOCK) >> 2) + 1;
 	lrclk_div = (1 << 22);
 	lrclk_div *= params_rate(params);
 	lrclk_div *= sf;
 	do_div(lrclk_div, max9850->sysclk);

 	snd_soc_write(codec, MAX9850_LRCLK_MSB, (lrclk_div >> 8) & 0x7f);
 	snd_soc_write(codec, MAX9850_LRCLK_LSB, lrclk_div & 0xff);

 	switch (params_width(params)) {
 	case 16:
 		da = 0;
 		break;
 	case 20:
 		da = 0x2;
 		break;
 	case 24:
 		da = 0x3;
 		break;
 	default:
 		return -EINVAL;
 	}
 	snd_soc_update_bits(codec, MAX9850_DIGITAL_AUDIO, 0x3, da);

 	return 0;
 }

 static int max9850_set_dai_sysclk(struct snd_soc_dai *codec_dai,
 		int clk_id, unsigned int freq, int dir)
 {
 	struct snd_soc_codec *codec = codec_dai->codec;
 	struct max9850_priv *max9850 = snd_soc_codec_get_drvdata(codec);

 	/* calculate mclk -> iclk divider */
 	if (freq <= 13000000)
 		snd_soc_write(codec, MAX9850_CLOCK, 0x0);
 	else if (freq <= 26000000)
 		snd_soc_write(codec, MAX9850_CLOCK, 0x4);
 	else if (freq <= 40000000)
 		snd_soc_write(codec, MAX9850_CLOCK, 0x8);
 	else
 		return -EINVAL;

 	max9850->sysclk = freq;
 	return 0;
 }

 static int max9850_set_dai_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
 {
 	struct snd_soc_codec *codec = codec_dai->codec;
 	u8 da = 0;

 	/* set master/slave audio interface */
 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
 	case SND_SOC_DAIFMT_CBM_CFM:
 		da |= MAX9850_MASTER;
 		break;
 	case SND_SOC_DAIFMT_CBS_CFS:
 		break;
 	default:
 		return -EINVAL;
 	}

 	/* interface format */
 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 	case SND_SOC_DAIFMT_I2S:
 		da |= MAX9850_DLY;
 		break;
 	case SND_SOC_DAIFMT_RIGHT_J:
 		da |= MAX9850_RTJ;
 		break;
 	case SND_SOC_DAIFMT_LEFT_J:
 		break;
 	default:
 		return -EINVAL;
 	}

 	/* clock inversion */
 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
 	case SND_SOC_DAIFMT_NB_NF:
 		break;
 	case SND_SOC_DAIFMT_IB_IF:
 		da |= MAX9850_BCINV | MAX9850_INV;
 		break;
 	case SND_SOC_DAIFMT_IB_NF:
 		da |= MAX9850_BCINV;
 		break;
 	case SND_SOC_DAIFMT_NB_IF:
 		da |= MAX9850_INV;
 		break;
 	default:
 		return -EINVAL;
 	}

 	/* set da */
 	snd_soc_write(codec, MAX9850_DIGITAL_AUDIO, da);

 	return 0;
 }

 static int max9850_set_bias_level(struct snd_soc_codec *codec,
 				  enum snd_soc_bias_level level)
 {
 	struct max9850_priv *max9850 = snd_soc_codec_get_drvdata(codec);
 	int ret;

 	switch (level) {
 	case SND_SOC_BIAS_ON:
 		break;
 	case SND_SOC_BIAS_PREPARE:
 		break;
 	case SND_SOC_BIAS_STANDBY:
 		if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
 			ret = regcache_sync(max9850->regmap);
 			if (ret) {
 				dev_err(codec->dev,
 					"Failed to sync cache: %d\n", ret);
 				return ret;
 			}
 		}
 		break;
 	case SND_SOC_BIAS_OFF:
 		break;
 	}
 	codec->dapm.bias_level = level;
 	return 0;
 }

 #define MAX9850_RATES SNDRV_PCM_RATE_8000_48000

 #define MAX9850_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE |\
 	SNDRV_PCM_FMTBIT_S24_LE)

 static const struct snd_soc_dai_ops max9850_dai_ops = {
 	.hw_params	= max9850_hw_params,
 	.set_sysclk	= max9850_set_dai_sysclk,
 	.set_fmt	= max9850_set_dai_fmt,
 };

 static struct snd_soc_dai_driver max9850_dai = {
 	.name = "max9850-hifi",
 	.playback = {
 		.stream_name = "Playback",
 		.channels_min = 1,
 		.channels_max = 2,
 		.rates = MAX9850_RATES,
 		.formats = MAX9850_FORMATS
 	},
 	.ops = &max9850_dai_ops,
 };

 static int max9850_probe(struct snd_soc_codec *codec)
 {
 	/* enable zero-detect */
 	snd_soc_update_bits(codec, MAX9850_GENERAL_PURPOSE, 1, 1);
 	/* enable slew-rate control */
 	snd_soc_update_bits(codec, MAX9850_VOLUME, 0x40, 0x40);
 	/* set slew-rate 125ms */
 	snd_soc_update_bits(codec, MAX9850_CHARGE_PUMP, 0xff, 0xc0);

 	return 0;
 }

 static struct snd_soc_codec_driver soc_codec_dev_max9850 = {
 	.probe =	max9850_probe,
 	.set_bias_level = max9850_set_bias_level,
 	.suspend_bias_off = true,

 	.controls = max9850_controls,
 	.num_controls = ARRAY_SIZE(max9850_controls),
 	.dapm_widgets = max9850_dapm_widgets,
 	.num_dapm_widgets = ARRAY_SIZE(max9850_dapm_widgets),
 	.dapm_routes = max9850_dapm_routes,
 	.num_dapm_routes = ARRAY_SIZE(max9850_dapm_routes),
 };

 static int max9850_i2c_probe(struct i2c_client *i2c,
 			     const struct i2c_device_id *id)
 {
 	struct max9850_priv *max9850;
 	int ret;

 	max9850 = devm_kzalloc(&i2c->dev, sizeof(struct max9850_priv),
 			       GFP_KERNEL);
 	if (max9850 == NULL)
 		return -ENOMEM;

 	max9850->regmap = devm_regmap_init_i2c(i2c, &max9850_regmap);
 	if (IS_ERR(max9850->regmap))
 		return PTR_ERR(max9850->regmap);

 	i2c_set_clientdata(i2c, max9850);

 	ret = snd_soc_register_codec(&i2c->dev,
 			&soc_codec_dev_max9850, &max9850_dai, 1);
 	return ret;
 }

 static int max9850_i2c_remove(struct i2c_client *client)
 {
 	snd_soc_unregister_codec(&client->dev);
 	return 0;
 }

 static const struct i2c_device_id max9850_i2c_id[] = {
 	{ "max9850", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, max9850_i2c_id);

 static struct i2c_driver max9850_i2c_driver = {
 	.driver = {
 		.name = "max9850",
 		.owner = THIS_MODULE,
 	},
 	.probe = max9850_i2c_probe,
 	.remove = max9850_i2c_remove,
 	.id_table = max9850_i2c_id,
 };

 module_i2c_driver(max9850_i2c_driver);

 MODULE_AUTHOR("Christian Glindkamp <christian.glindkamp@taskit.de>");
 MODULE_DESCRIPTION("ASoC MAX9850 codec driver");
 MODULE_LICENSE("GPL");
	/*
	* max9850.c -- codec driver for max9850
	*
	* Copyright (C) 2011 taskit GmbH
	*
	* Author: Christian Glindkamp <christian.glindkamp@taskit.de>
	*
	* Initial development of this code was funded by
	* MICRONIC Computer Systeme GmbH, http://www.mcsberlin.de/
	*
	* 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 <linux/regmap.h>
	#include <linux/slab.h>
	#include <sound/pcm.h>
	#include <sound/pcm_params.h>
	#include <sound/soc.h>
	#include <sound/tlv.h>

	#include "max9850.h"

	struct max9850_priv {
	struct regmap *regmap;
	unsigned int sysclk;
	};

	/* max9850 register cache */
	static const struct reg_default max9850_reg[] = {
	{ 2, 0x0c },
	{ 3, 0x00 },
	{ 4, 0x00 },
	{ 5, 0x00 },
	{ 6, 0x00 },
	{ 7, 0x00 },
	{ 8, 0x00 },
	{ 9, 0x00 },
	{ 10, 0x00 },
	};

	/* these registers are not used at the moment but provided for the sake of
	* completeness */
	static bool max9850_volatile_register(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case MAX9850_STATUSA:
	case MAX9850_STATUSB:
	return 1;
	default:
	return 0;
	}
	}

	static const struct regmap_config max9850_regmap = {
	.reg_bits = 8,
	.val_bits = 8,

	.max_register = MAX9850_DIGITAL_AUDIO,
	.volatile_reg = max9850_volatile_register,
	.cache_type = REGCACHE_RBTREE,
	};

	static const unsigned int max9850_tlv[] = {
	TLV_DB_RANGE_HEAD(4),
	0x18, 0x1f, TLV_DB_SCALE_ITEM(-7450, 400, 0),
	0x20, 0x33, TLV_DB_SCALE_ITEM(-4150, 200, 0),
	0x34, 0x37, TLV_DB_SCALE_ITEM(-150, 100, 0),
	0x38, 0x3f, TLV_DB_SCALE_ITEM(250, 50, 0),
	};

	static const struct snd_kcontrol_new max9850_controls[] = {
	SOC_SINGLE_TLV("Headphone Volume", MAX9850_VOLUME, 0, 0x3f, 1, max9850_tlv),
	SOC_SINGLE("Headphone Switch", MAX9850_VOLUME, 7, 1, 1),
	SOC_SINGLE("Mono Switch", MAX9850_GENERAL_PURPOSE, 2, 1, 0),
	};

	static const struct snd_kcontrol_new max9850_mixer_controls[] = {
	SOC_DAPM_SINGLE("Line In Switch", MAX9850_ENABLE, 1, 1, 0),
	};

	static const struct snd_soc_dapm_widget max9850_dapm_widgets[] = {
	SND_SOC_DAPM_SUPPLY("Charge Pump 1", MAX9850_ENABLE, 4, 0, NULL, 0),
	SND_SOC_DAPM_SUPPLY("Charge Pump 2", MAX9850_ENABLE, 5, 0, NULL, 0),
	SND_SOC_DAPM_SUPPLY("MCLK", MAX9850_ENABLE, 6, 0, NULL, 0),
	SND_SOC_DAPM_SUPPLY("SHDN", MAX9850_ENABLE, 7, 0, NULL, 0),
	SND_SOC_DAPM_MIXER_NAMED_CTL("Output Mixer", MAX9850_ENABLE, 2, 0,
	&max9850_mixer_controls[0],
	ARRAY_SIZE(max9850_mixer_controls)),
	SND_SOC_DAPM_PGA("Headphone Output", MAX9850_ENABLE, 3, 0, NULL, 0),
	SND_SOC_DAPM_DAC("DAC", "HiFi Playback", MAX9850_ENABLE, 0, 0),
	SND_SOC_DAPM_OUTPUT("OUTL"),
	SND_SOC_DAPM_OUTPUT("HPL"),
	SND_SOC_DAPM_OUTPUT("OUTR"),
	SND_SOC_DAPM_OUTPUT("HPR"),
	SND_SOC_DAPM_MIXER("Line Input", SND_SOC_NOPM, 0, 0, NULL, 0),
	SND_SOC_DAPM_INPUT("INL"),
	SND_SOC_DAPM_INPUT("INR"),
	};

	static const struct snd_soc_dapm_route max9850_dapm_routes[] = {
	/* output mixer */
	{"Output Mixer", NULL, "DAC"},
	{"Output Mixer", "Line In Switch", "Line Input"},

	/* outputs */
	{"Headphone Output", NULL, "Output Mixer"},
	{"HPL", NULL, "Headphone Output"},
	{"HPR", NULL, "Headphone Output"},
	{"OUTL", NULL, "Output Mixer"},
	{"OUTR", NULL, "Output Mixer"},

	/* inputs */
	{"Line Input", NULL, "INL"},
	{"Line Input", NULL, "INR"},

	/* supplies */
	{"Output Mixer", NULL, "Charge Pump 1"},
	{"Output Mixer", NULL, "Charge Pump 2"},
	{"Output Mixer", NULL, "SHDN"},
	{"DAC", NULL, "MCLK"},
	};

	static int max9850_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params,
	struct snd_soc_dai *dai)
	{
	struct snd_soc_codec *codec = dai->codec;
	struct max9850_priv *max9850 = snd_soc_codec_get_drvdata(codec);
	u64 lrclk_div;
	u8 sf, da;

	if (!max9850->sysclk)
	return -EINVAL;

	/* lrclk_div = 2^22 * rate / iclk with iclk = mclk / sf */
	sf = (snd_soc_read(codec, MAX9850_CLOCK) >> 2) + 1;
	lrclk_div = (1 << 22);
	lrclk_div *= params_rate(params);
	lrclk_div *= sf;
	do_div(lrclk_div, max9850->sysclk);

	snd_soc_write(codec, MAX9850_LRCLK_MSB, (lrclk_div >> 8) & 0x7f);
	snd_soc_write(codec, MAX9850_LRCLK_LSB, lrclk_div & 0xff);

	switch (params_width(params)) {
	case 16:
	da = 0;
	break;
	case 20:
	da = 0x2;
	break;
	case 24:
	da = 0x3;
	break;
	default:
	return -EINVAL;
	}
	snd_soc_update_bits(codec, MAX9850_DIGITAL_AUDIO, 0x3, da);

	return 0;
	}

	static int max9850_set_dai_sysclk(struct snd_soc_dai *codec_dai,
	int clk_id, unsigned int freq, int dir)
	{
	struct snd_soc_codec *codec = codec_dai->codec;
	struct max9850_priv *max9850 = snd_soc_codec_get_drvdata(codec);

	/* calculate mclk -> iclk divider */
	if (freq <= 13000000)
	snd_soc_write(codec, MAX9850_CLOCK, 0x0);
	else if (freq <= 26000000)
	snd_soc_write(codec, MAX9850_CLOCK, 0x4);
	else if (freq <= 40000000)
	snd_soc_write(codec, MAX9850_CLOCK, 0x8);
	else
	return -EINVAL;

	max9850->sysclk = freq;
	return 0;
	}

	static int max9850_set_dai_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
	{
	struct snd_soc_codec *codec = codec_dai->codec;
	u8 da = 0;

	/* set master/slave audio interface */
	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
	case SND_SOC_DAIFMT_CBM_CFM:
	da \|= MAX9850_MASTER;
	break;
	case SND_SOC_DAIFMT_CBS_CFS:
	break;
	default:
	return -EINVAL;
	}

	/* interface format */
	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
	case SND_SOC_DAIFMT_I2S:
	da \|= MAX9850_DLY;
	break;
	case SND_SOC_DAIFMT_RIGHT_J:
	da \|= MAX9850_RTJ;
	break;
	case SND_SOC_DAIFMT_LEFT_J:
	break;
	default:
	return -EINVAL;
	}

	/* clock inversion */
	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
	case SND_SOC_DAIFMT_NB_NF:
	break;
	case SND_SOC_DAIFMT_IB_IF:
	da \|= MAX9850_BCINV \| MAX9850_INV;
	break;
	case SND_SOC_DAIFMT_IB_NF:
	da \|= MAX9850_BCINV;
	break;
	case SND_SOC_DAIFMT_NB_IF:
	da \|= MAX9850_INV;
	break;
	default:
	return -EINVAL;
	}

	/* set da */
	snd_soc_write(codec, MAX9850_DIGITAL_AUDIO, da);

	return 0;
	}

	static int max9850_set_bias_level(struct snd_soc_codec *codec,
	enum snd_soc_bias_level level)
	{
	struct max9850_priv *max9850 = snd_soc_codec_get_drvdata(codec);
	int ret;

	switch (level) {
	case SND_SOC_BIAS_ON:
	break;
	case SND_SOC_BIAS_PREPARE:
	break;
	case SND_SOC_BIAS_STANDBY:
	if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
	ret = regcache_sync(max9850->regmap);
	if (ret) {
	dev_err(codec->dev,
	"Failed to sync cache: %d\n", ret);
	return ret;
	}
	}
	break;
	case SND_SOC_BIAS_OFF:
	break;
	}
	codec->dapm.bias_level = level;
	return 0;
	}

	#define MAX9850_RATES SNDRV_PCM_RATE_8000_48000

	#define MAX9850_FORMATS (SNDRV_PCM_FMTBIT_S16_LE \| SNDRV_PCM_FMTBIT_S20_3LE \|\
	SNDRV_PCM_FMTBIT_S24_LE)

	static const struct snd_soc_dai_ops max9850_dai_ops = {
	.hw_params = max9850_hw_params,
	.set_sysclk = max9850_set_dai_sysclk,
	.set_fmt = max9850_set_dai_fmt,
	};

	static struct snd_soc_dai_driver max9850_dai = {
	.name = "max9850-hifi",
	.playback = {
	.stream_name = "Playback",
	.channels_min = 1,
	.channels_max = 2,
	.rates = MAX9850_RATES,
	.formats = MAX9850_FORMATS
	},
	.ops = &max9850_dai_ops,
	};

	static int max9850_probe(struct snd_soc_codec *codec)
	{
	/* enable zero-detect */
	snd_soc_update_bits(codec, MAX9850_GENERAL_PURPOSE, 1, 1);
	/* enable slew-rate control */
	snd_soc_update_bits(codec, MAX9850_VOLUME, 0x40, 0x40);
	/* set slew-rate 125ms */
	snd_soc_update_bits(codec, MAX9850_CHARGE_PUMP, 0xff, 0xc0);

	return 0;
	}

	static struct snd_soc_codec_driver soc_codec_dev_max9850 = {
	.probe = max9850_probe,
	.set_bias_level = max9850_set_bias_level,
	.suspend_bias_off = true,

	.controls = max9850_controls,
	.num_controls = ARRAY_SIZE(max9850_controls),
	.dapm_widgets = max9850_dapm_widgets,
	.num_dapm_widgets = ARRAY_SIZE(max9850_dapm_widgets),
	.dapm_routes = max9850_dapm_routes,
	.num_dapm_routes = ARRAY_SIZE(max9850_dapm_routes),
	};

	static int max9850_i2c_probe(struct i2c_client *i2c,
	const struct i2c_device_id *id)
	{
	struct max9850_priv *max9850;
	int ret;

	max9850 = devm_kzalloc(&i2c->dev, sizeof(struct max9850_priv),
	GFP_KERNEL);
	if (max9850 == NULL)
	return -ENOMEM;

	max9850->regmap = devm_regmap_init_i2c(i2c, &max9850_regmap);
	if (IS_ERR(max9850->regmap))
	return PTR_ERR(max9850->regmap);

	i2c_set_clientdata(i2c, max9850);

	ret = snd_soc_register_codec(&i2c->dev,
	&soc_codec_dev_max9850, &max9850_dai, 1);
	return ret;
	}

	static int max9850_i2c_remove(struct i2c_client *client)
	{
	snd_soc_unregister_codec(&client->dev);
	return 0;
	}

	static const struct i2c_device_id max9850_i2c_id[] = {
	{ "max9850", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, max9850_i2c_id);

	static struct i2c_driver max9850_i2c_driver = {
	.driver = {
	.name = "max9850",
	.owner = THIS_MODULE,
	},
	.probe = max9850_i2c_probe,
	.remove = max9850_i2c_remove,
	.id_table = max9850_i2c_id,
	};

	module_i2c_driver(max9850_i2c_driver);

	MODULE_AUTHOR("Christian Glindkamp <christian.glindkamp@taskit.de>");
	MODULE_DESCRIPTION("ASoC MAX9850 codec driver");
	MODULE_LICENSE("GPL");