text: /*
   * 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 DECLARE_TLV_DB_RANGE(max9850_tlv,
  	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 (snd_soc_codec_get_bias_level(codec) == 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;
  	}
  	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,
  
  	.component_driver = {
  		.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",
  	},
  	.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");
  