/*
   * wm8523.c  --  WM8523 ALSA SoC Audio driver
   *
   * Copyright 2009 Wolfson Microelectronics plc
   *
   * Author: Mark Brown <broonie@opensource.wolfsonmicro.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.
   */
  
  #include <linux/module.h>
  #include <linux/moduleparam.h>
  #include <linux/init.h>
  #include <linux/delay.h>
  #include <linux/pm.h>
  #include <linux/i2c.h>
  #include <linux/regmap.h>
  #include <linux/regulator/consumer.h>
  #include <linux/slab.h>
  #include <linux/of_device.h>
  #include <sound/core.h>
  #include <sound/pcm.h>
  #include <sound/pcm_params.h>
  #include <sound/soc.h>
  #include <sound/initval.h>
  #include <sound/tlv.h>
  
  #include "wm8523.h"
  
  #define WM8523_NUM_SUPPLIES 2
  static const char *wm8523_supply_names[WM8523_NUM_SUPPLIES] = {
  	"AVDD",
  	"LINEVDD",
  };
  
  #define WM8523_NUM_RATES 7
  
  /* codec private data */
  struct wm8523_priv {
  	struct regmap *regmap;
  	struct regulator_bulk_data supplies[WM8523_NUM_SUPPLIES];
  	unsigned int sysclk;
  	unsigned int rate_constraint_list[WM8523_NUM_RATES];
  	struct snd_pcm_hw_constraint_list rate_constraint;
  };
  
  static const struct reg_default wm8523_reg_defaults[] = {
  	{ 2, 0x0000 },     /* R2 - PSCTRL1 */
  	{ 3, 0x1812 },     /* R3 - AIF_CTRL1 */
  	{ 4, 0x0000 },     /* R4 - AIF_CTRL2 */
  	{ 5, 0x0001 },     /* R5 - DAC_CTRL3 */
  	{ 6, 0x0190 },     /* R6 - DAC_GAINL */
  	{ 7, 0x0190 },     /* R7 - DAC_GAINR */
  	{ 8, 0x0000 },     /* R8 - ZERO_DETECT */
  };
  
  static bool wm8523_volatile_register(struct device *dev, unsigned int reg)
  {
  	switch (reg) {
  	case WM8523_DEVICE_ID:
  	case WM8523_REVISION:
  		return true;
  	default:
  		return false;
  	}
  }
  
  static const DECLARE_TLV_DB_SCALE(dac_tlv, -10000, 25, 0);
  
  static const char *wm8523_zd_count_text[] = {
  	"1024",
  	"2048",
  };
  
  static const struct soc_enum wm8523_zc_count =
  	SOC_ENUM_SINGLE(WM8523_ZERO_DETECT, 0, 2, wm8523_zd_count_text);
  
  static const struct snd_kcontrol_new wm8523_controls[] = {
  SOC_DOUBLE_R_TLV("Playback Volume", WM8523_DAC_GAINL, WM8523_DAC_GAINR,
  		 0, 448, 0, dac_tlv),
  SOC_SINGLE("ZC Switch", WM8523_DAC_CTRL3, 4, 1, 0),
  SOC_SINGLE("Playback Deemphasis Switch", WM8523_AIF_CTRL1, 8, 1, 0),
  SOC_DOUBLE("Playback Switch", WM8523_DAC_CTRL3, 2, 3, 1, 1),
  SOC_SINGLE("Volume Ramp Up Switch", WM8523_DAC_CTRL3, 1, 1, 0),
  SOC_SINGLE("Volume Ramp Down Switch", WM8523_DAC_CTRL3, 0, 1, 0),
  SOC_ENUM("Zero Detect Count", wm8523_zc_count),
  };
  
  static const struct snd_soc_dapm_widget wm8523_dapm_widgets[] = {
  SND_SOC_DAPM_DAC("DAC", "Playback", SND_SOC_NOPM, 0, 0),
  SND_SOC_DAPM_OUTPUT("LINEVOUTL"),
  SND_SOC_DAPM_OUTPUT("LINEVOUTR"),
  };
  
  static const struct snd_soc_dapm_route wm8523_dapm_routes[] = {
  	{ "LINEVOUTL", NULL, "DAC" },
  	{ "LINEVOUTR", NULL, "DAC" },
  };
  
  static struct {
  	int value;
  	int ratio;
  } lrclk_ratios[WM8523_NUM_RATES] = {
  	{ 1, 128 },
  	{ 2, 192 },
  	{ 3, 256 },
  	{ 4, 384 },
  	{ 5, 512 },
  	{ 6, 768 },
  	{ 7, 1152 },
  };
  
  static int wm8523_startup(struct snd_pcm_substream *substream,
  			  struct snd_soc_dai *dai)
  {
  	struct snd_soc_codec *codec = dai->codec;
  	struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
  
  	/* The set of sample rates that can be supported depends on the
  	 * MCLK supplied to the CODEC - enforce this.
  	 */
  	if (!wm8523->sysclk) {
  		dev_err(codec->dev,
  			"No MCLK configured, call set_sysclk() on init
  ");
  		return -EINVAL;
  	}
  
  	snd_pcm_hw_constraint_list(substream->runtime, 0,
  				   SNDRV_PCM_HW_PARAM_RATE,
  				   &wm8523->rate_constraint);
  
  	return 0;
  }
  
  static int wm8523_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 wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
  	int i;
  	u16 aifctrl1 = snd_soc_read(codec, WM8523_AIF_CTRL1);
  	u16 aifctrl2 = snd_soc_read(codec, WM8523_AIF_CTRL2);
  
  	/* Find a supported LRCLK ratio */
  	for (i = 0; i < ARRAY_SIZE(lrclk_ratios); i++) {
  		if (wm8523->sysclk / params_rate(params) ==
  		    lrclk_ratios[i].ratio)
  			break;
  	}
  
  	/* Should never happen, should be handled by constraints */
  	if (i == ARRAY_SIZE(lrclk_ratios)) {
  		dev_err(codec->dev, "MCLK/fs ratio %d unsupported
  ",
  			wm8523->sysclk / params_rate(params));
  		return -EINVAL;
  	}
  
  	aifctrl2 &= ~WM8523_SR_MASK;
  	aifctrl2 |= lrclk_ratios[i].value;
  
  	aifctrl1 &= ~WM8523_WL_MASK;
  	switch (params_format(params)) {
  	case SNDRV_PCM_FORMAT_S16_LE:
  		break;
  	case SNDRV_PCM_FORMAT_S20_3LE:
  		aifctrl1 |= 0x8;
  		break;
  	case SNDRV_PCM_FORMAT_S24_LE:
  		aifctrl1 |= 0x10;
  		break;
  	case SNDRV_PCM_FORMAT_S32_LE:
  		aifctrl1 |= 0x18;
  		break;
  	}
  
  	snd_soc_write(codec, WM8523_AIF_CTRL1, aifctrl1);
  	snd_soc_write(codec, WM8523_AIF_CTRL2, aifctrl2);
  
  	return 0;
  }
  
  static int wm8523_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 wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
  	unsigned int val;
  	int i;
  
  	wm8523->sysclk = freq;
  
  	wm8523->rate_constraint.count = 0;
  	for (i = 0; i < ARRAY_SIZE(lrclk_ratios); i++) {
  		val = freq / lrclk_ratios[i].ratio;
  		/* Check that it's a standard rate since core can't
  		 * cope with others and having the odd rates confuses
  		 * constraint matching.
  		 */
  		switch (val) {
  		case 8000:
  		case 11025:
  		case 16000:
  		case 22050:
  		case 32000:
  		case 44100:
  		case 48000:
  		case 64000:
  		case 88200:
  		case 96000:
  		case 176400:
  		case 192000:
  			dev_dbg(codec->dev, "Supported sample rate: %dHz
  ",
  				val);
  			wm8523->rate_constraint_list[i] = val;
  			wm8523->rate_constraint.count++;
  			break;
  		default:
  			dev_dbg(codec->dev, "Skipping sample rate: %dHz
  ",
  				val);
  		}
  	}
  
  	/* Need at least one supported rate... */
  	if (wm8523->rate_constraint.count == 0)
  		return -EINVAL;
  
  	return 0;
  }
  
  
  static int wm8523_set_dai_fmt(struct snd_soc_dai *codec_dai,
  		unsigned int fmt)
  {
  	struct snd_soc_codec *codec = codec_dai->codec;
  	u16 aifctrl1 = snd_soc_read(codec, WM8523_AIF_CTRL1);
  
  	aifctrl1 &= ~(WM8523_BCLK_INV_MASK | WM8523_LRCLK_INV_MASK |
  		      WM8523_FMT_MASK | WM8523_AIF_MSTR_MASK);
  
  	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
  	case SND_SOC_DAIFMT_CBM_CFM:
  		aifctrl1 |= WM8523_AIF_MSTR;
  		break;
  	case SND_SOC_DAIFMT_CBS_CFS:
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
  	case SND_SOC_DAIFMT_I2S:
  		aifctrl1 |= 0x0002;
  		break;
  	case SND_SOC_DAIFMT_RIGHT_J:
  		break;
  	case SND_SOC_DAIFMT_LEFT_J:
  		aifctrl1 |= 0x0001;
  		break;
  	case SND_SOC_DAIFMT_DSP_A:
  		aifctrl1 |= 0x0003;
  		break;
  	case SND_SOC_DAIFMT_DSP_B:
  		aifctrl1 |= 0x0023;
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
  	case SND_SOC_DAIFMT_NB_NF:
  		break;
  	case SND_SOC_DAIFMT_IB_IF:
  		aifctrl1 |= WM8523_BCLK_INV | WM8523_LRCLK_INV;
  		break;
  	case SND_SOC_DAIFMT_IB_NF:
  		aifctrl1 |= WM8523_BCLK_INV;
  		break;
  	case SND_SOC_DAIFMT_NB_IF:
  		aifctrl1 |= WM8523_LRCLK_INV;
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	snd_soc_write(codec, WM8523_AIF_CTRL1, aifctrl1);
  
  	return 0;
  }
  
  static int wm8523_set_bias_level(struct snd_soc_codec *codec,
  				 enum snd_soc_bias_level level)
  {
  	struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
  	int ret;
  
  	switch (level) {
  	case SND_SOC_BIAS_ON:
  		break;
  
  	case SND_SOC_BIAS_PREPARE:
  		/* Full power on */
  		snd_soc_update_bits(codec, WM8523_PSCTRL1,
  				    WM8523_SYS_ENA_MASK, 3);
  		break;
  
  	case SND_SOC_BIAS_STANDBY:
  		if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
  			ret = regulator_bulk_enable(ARRAY_SIZE(wm8523->supplies),
  						    wm8523->supplies);
  			if (ret != 0) {
  				dev_err(codec->dev,
  					"Failed to enable supplies: %d
  ",
  					ret);
  				return ret;
  			}
  
  			/* Sync back default/cached values */
  			regcache_sync(wm8523->regmap);
  
  			/* Initial power up */
  			snd_soc_update_bits(codec, WM8523_PSCTRL1,
  					    WM8523_SYS_ENA_MASK, 1);
  
  			msleep(100);
  		}
  
  		/* Power up to mute */
  		snd_soc_update_bits(codec, WM8523_PSCTRL1,
  				    WM8523_SYS_ENA_MASK, 2);
  
  		break;
  
  	case SND_SOC_BIAS_OFF:
  		/* The chip runs through the power down sequence for us. */
  		snd_soc_update_bits(codec, WM8523_PSCTRL1,
  				    WM8523_SYS_ENA_MASK, 0);
  		msleep(100);
  
  		regulator_bulk_disable(ARRAY_SIZE(wm8523->supplies),
  				       wm8523->supplies);
  		break;
  	}
  	codec->dapm.bias_level = level;
  	return 0;
  }
  
  #define WM8523_RATES SNDRV_PCM_RATE_8000_192000
  
  #define WM8523_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE |\
  			SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
  
  static const struct snd_soc_dai_ops wm8523_dai_ops = {
  	.startup	= wm8523_startup,
  	.hw_params	= wm8523_hw_params,
  	.set_sysclk	= wm8523_set_dai_sysclk,
  	.set_fmt	= wm8523_set_dai_fmt,
  };
  
  static struct snd_soc_dai_driver wm8523_dai = {
  	.name = "wm8523-hifi",
  	.playback = {
  		.stream_name = "Playback",
  		.channels_min = 2,  /* Mono modes not yet supported */
  		.channels_max = 2,
  		.rates = WM8523_RATES,
  		.formats = WM8523_FORMATS,
  	},
  	.ops = &wm8523_dai_ops,
  };
  
  #ifdef CONFIG_PM
  static int wm8523_suspend(struct snd_soc_codec *codec)
  {
  	wm8523_set_bias_level(codec, SND_SOC_BIAS_OFF);
  	return 0;
  }
  
  static int wm8523_resume(struct snd_soc_codec *codec)
  {
  	wm8523_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
  	return 0;
  }
  #else
  #define wm8523_suspend NULL
  #define wm8523_resume NULL
  #endif
  
  static int wm8523_probe(struct snd_soc_codec *codec)
  {
  	struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
  	int ret;
  
  	wm8523->rate_constraint.list = &wm8523->rate_constraint_list[0];
  	wm8523->rate_constraint.count =
  		ARRAY_SIZE(wm8523->rate_constraint_list);
  
  	ret = snd_soc_codec_set_cache_io(codec, 8, 16, SND_SOC_REGMAP);
  	if (ret != 0) {
  		dev_err(codec->dev, "Failed to set cache I/O: %d
  ", ret);
  		return ret;
  	}
  
  	/* Change some default settings - latch VU and enable ZC */
  	snd_soc_update_bits(codec, WM8523_DAC_GAINR,
  			    WM8523_DACR_VU, WM8523_DACR_VU);
  	snd_soc_update_bits(codec, WM8523_DAC_CTRL3, WM8523_ZC, WM8523_ZC);
  
  	wm8523_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
  
  	return 0;
  }
  
  static int wm8523_remove(struct snd_soc_codec *codec)
  {
  	wm8523_set_bias_level(codec, SND_SOC_BIAS_OFF);
  	return 0;
  }
  
  static struct snd_soc_codec_driver soc_codec_dev_wm8523 = {
  	.probe =	wm8523_probe,
  	.remove =	wm8523_remove,
  	.suspend =	wm8523_suspend,
  	.resume =	wm8523_resume,
  	.set_bias_level = wm8523_set_bias_level,
  
  	.controls = wm8523_controls,
  	.num_controls = ARRAY_SIZE(wm8523_controls),
  	.dapm_widgets = wm8523_dapm_widgets,
  	.num_dapm_widgets = ARRAY_SIZE(wm8523_dapm_widgets),
  	.dapm_routes = wm8523_dapm_routes,
  	.num_dapm_routes = ARRAY_SIZE(wm8523_dapm_routes),
  };
  
  static const struct of_device_id wm8523_of_match[] = {
  	{ .compatible = "wlf,wm8523" },
  	{ },
  };
  
  static const struct regmap_config wm8523_regmap = {
  	.reg_bits = 8,
  	.val_bits = 16,
  	.max_register = WM8523_ZERO_DETECT,
  
  	.reg_defaults = wm8523_reg_defaults,
  	.num_reg_defaults = ARRAY_SIZE(wm8523_reg_defaults),
  	.cache_type = REGCACHE_RBTREE,
  
  	.volatile_reg = wm8523_volatile_register,
  };
  
  #if IS_ENABLED(CONFIG_I2C)
  static int wm8523_i2c_probe(struct i2c_client *i2c,
  			    const struct i2c_device_id *id)
  {
  	struct wm8523_priv *wm8523;
  	unsigned int val;
  	int ret, i;
  
  	wm8523 = devm_kzalloc(&i2c->dev, sizeof(struct wm8523_priv),
  			      GFP_KERNEL);
  	if (wm8523 == NULL)
  		return -ENOMEM;
  
  	wm8523->regmap = devm_regmap_init_i2c(i2c, &wm8523_regmap);
  	if (IS_ERR(wm8523->regmap)) {
  		ret = PTR_ERR(wm8523->regmap);
  		dev_err(&i2c->dev, "Failed to create regmap: %d
  ", ret);
  		return ret;
  	}
  
  	for (i = 0; i < ARRAY_SIZE(wm8523->supplies); i++)
  		wm8523->supplies[i].supply = wm8523_supply_names[i];
  
  	ret = devm_regulator_bulk_get(&i2c->dev, ARRAY_SIZE(wm8523->supplies),
  				      wm8523->supplies);
  	if (ret != 0) {
  		dev_err(&i2c->dev, "Failed to request supplies: %d
  ", ret);
  		return ret;
  	}
  
  	ret = regulator_bulk_enable(ARRAY_SIZE(wm8523->supplies),
  				    wm8523->supplies);
  	if (ret != 0) {
  		dev_err(&i2c->dev, "Failed to enable supplies: %d
  ", ret);
  		return ret;
  	}
  
  	ret = regmap_read(wm8523->regmap, WM8523_DEVICE_ID, &val);
  	if (ret < 0) {
  		dev_err(&i2c->dev, "Failed to read ID register
  ");
  		goto err_enable;
  	}
  	if (val != 0x8523) {
  		dev_err(&i2c->dev, "Device is not a WM8523, ID is %x
  ", ret);
  		ret = -EINVAL;
  		goto err_enable;
  	}
  
  	ret = regmap_read(wm8523->regmap, WM8523_REVISION, &val);
  	if (ret < 0) {
  		dev_err(&i2c->dev, "Failed to read revision register
  ");
  		goto err_enable;
  	}
  	dev_info(&i2c->dev, "revision %c
  ",
  		 (val & WM8523_CHIP_REV_MASK) + 'A');
  
  	ret = regmap_write(wm8523->regmap, WM8523_DEVICE_ID, 0x8523);
  	if (ret != 0) {
  		dev_err(&i2c->dev, "Failed to reset device: %d
  ", ret);
  		goto err_enable;
  	}
  
  	regulator_bulk_disable(ARRAY_SIZE(wm8523->supplies), wm8523->supplies);
  
  	i2c_set_clientdata(i2c, wm8523);
  
  	ret =  snd_soc_register_codec(&i2c->dev,
  			&soc_codec_dev_wm8523, &wm8523_dai, 1);
  
  	return ret;
  
  err_enable:
  	regulator_bulk_disable(ARRAY_SIZE(wm8523->supplies), wm8523->supplies);
  	return ret;
  }
  
  static int wm8523_i2c_remove(struct i2c_client *client)
  {
  	snd_soc_unregister_codec(&client->dev);
  	return 0;
  }
  
  static const struct i2c_device_id wm8523_i2c_id[] = {
  	{ "wm8523", 0 },
  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, wm8523_i2c_id);
  
  static struct i2c_driver wm8523_i2c_driver = {
  	.driver = {
  		.name = "wm8523",
  		.owner = THIS_MODULE,
  		.of_match_table = wm8523_of_match,
  	},
  	.probe =    wm8523_i2c_probe,
  	.remove =   wm8523_i2c_remove,
  	.id_table = wm8523_i2c_id,
  };
  #endif
  
  static int __init wm8523_modinit(void)
  {
  	int ret;
  #if IS_ENABLED(CONFIG_I2C)
  	ret = i2c_add_driver(&wm8523_i2c_driver);
  	if (ret != 0) {
  		printk(KERN_ERR "Failed to register WM8523 I2C driver: %d
  ",
  		       ret);
  	}
  #endif
  	return 0;
  }
  module_init(wm8523_modinit);
  
  static void __exit wm8523_exit(void)
  {
  #if IS_ENABLED(CONFIG_I2C)
  	i2c_del_driver(&wm8523_i2c_driver);
  #endif
  }
  module_exit(wm8523_exit);
  
  MODULE_DESCRIPTION("ASoC WM8523 driver");
  MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
  MODULE_LICENSE("GPL");