/*
   * wm8994-core.c  --  Device access for Wolfson WM8994
   *
   * 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 as published by the
   *  Free Software Foundation;  either version 2 of the  License, or (at your
   *  option) any later version.
   *
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>

  #include <linux/slab.h>

  #include <linux/i2c.h>

  #include <linux/err.h>

  #include <linux/delay.h>
  #include <linux/mfd/core.h>

  #include <linux/pm_runtime.h>

  #include <linux/regmap.h>

  #include <linux/regulator/consumer.h>
  #include <linux/regulator/machine.h>
  
  #include <linux/mfd/wm8994/core.h>
  #include <linux/mfd/wm8994/pdata.h>
  #include <linux/mfd/wm8994/registers.h>

  #include "wm8994.h"

  
  /**
   * wm8994_reg_read: Read a single WM8994 register.
   *
   * @wm8994: Device to read from.
   * @reg: Register to read.
   */
  int wm8994_reg_read(struct wm8994 *wm8994, unsigned short reg)
  {

  	unsigned int val;

  	int ret;

  	ret = regmap_read(wm8994->regmap, reg, &val);

  
  	if (ret < 0)
  		return ret;
  	else

  		return val;

  }
  EXPORT_SYMBOL_GPL(wm8994_reg_read);
  
  /**
   * wm8994_bulk_read: Read multiple WM8994 registers
   *
   * @wm8994: Device to read from
   * @reg: First register
   * @count: Number of registers

   * @buf: Buffer to fill.  The data will be returned big endian.

   */
  int wm8994_bulk_read(struct wm8994 *wm8994, unsigned short reg,
  		     int count, u16 *buf)
  {

  	return regmap_bulk_read(wm8994->regmap, reg, buf, count);

  }

  /**
   * wm8994_reg_write: Write a single WM8994 register.
   *
   * @wm8994: Device to write to.
   * @reg: Register to write to.
   * @val: Value to write.
   */
  int wm8994_reg_write(struct wm8994 *wm8994, unsigned short reg,
  		     unsigned short val)
  {

  	return regmap_write(wm8994->regmap, reg, val);

  }
  EXPORT_SYMBOL_GPL(wm8994_reg_write);
  
  /**

   * wm8994_bulk_write: Write multiple WM8994 registers
   *
   * @wm8994: Device to write to
   * @reg: First register
   * @count: Number of registers

   * @buf: Buffer to write from.  Data must be big-endian formatted.

   */
  int wm8994_bulk_write(struct wm8994 *wm8994, unsigned short reg,

  		      int count, const u16 *buf)

  {

  	return regmap_raw_write(wm8994->regmap, reg, buf, count * sizeof(u16));

  }
  EXPORT_SYMBOL_GPL(wm8994_bulk_write);
  
  /**

   * wm8994_set_bits: Set the value of a bitfield in a WM8994 register
   *
   * @wm8994: Device to write to.
   * @reg: Register to write to.
   * @mask: Mask of bits to set.
   * @val: Value to set (unshifted)
   */
  int wm8994_set_bits(struct wm8994 *wm8994, unsigned short reg,
  		    unsigned short mask, unsigned short val)
  {

  	return regmap_update_bits(wm8994->regmap, reg, mask, val);

  }
  EXPORT_SYMBOL_GPL(wm8994_set_bits);
  
  static struct mfd_cell wm8994_regulator_devs[] = {

  	{
  		.name = "wm8994-ldo",
  		.id = 1,
  		.pm_runtime_no_callbacks = true,
  	},
  	{
  		.name = "wm8994-ldo",
  		.id = 2,
  		.pm_runtime_no_callbacks = true,
  	},

  };

  static struct resource wm8994_codec_resources[] = {
  	{
  		.start = WM8994_IRQ_TEMP_SHUT,
  		.end   = WM8994_IRQ_TEMP_WARN,
  		.flags = IORESOURCE_IRQ,
  	},
  };
  
  static struct resource wm8994_gpio_resources[] = {
  	{
  		.start = WM8994_IRQ_GPIO(1),
  		.end   = WM8994_IRQ_GPIO(11),
  		.flags = IORESOURCE_IRQ,
  	},
  };

  static struct mfd_cell wm8994_devs[] = {

  	{
  		.name = "wm8994-codec",
  		.num_resources = ARRAY_SIZE(wm8994_codec_resources),
  		.resources = wm8994_codec_resources,
  	},
  
  	{
  		.name = "wm8994-gpio",
  		.num_resources = ARRAY_SIZE(wm8994_gpio_resources),
  		.resources = wm8994_gpio_resources,

  		.pm_runtime_no_callbacks = true,

  	},

  };
  
  /*
   * Supplies for the main bulk of CODEC; the LDO supplies are ignored
   * and should be handled via the standard regulator API supply
   * management.
   */

  static const char *wm1811_main_supplies[] = {
  	"DBVDD1",
  	"DBVDD2",
  	"DBVDD3",
  	"DCVDD",
  	"AVDD1",
  	"AVDD2",
  	"CPVDD",
  	"SPKVDD1",
  	"SPKVDD2",
  };

  static const char *wm8994_main_supplies[] = {
  	"DBVDD",
  	"DCVDD",
  	"AVDD1",
  	"AVDD2",
  	"CPVDD",
  	"SPKVDD1",
  	"SPKVDD2",
  };

  static const char *wm8958_main_supplies[] = {
  	"DBVDD1",
  	"DBVDD2",
  	"DBVDD3",
  	"DCVDD",
  	"AVDD1",
  	"AVDD2",
  	"CPVDD",
  	"SPKVDD1",
  	"SPKVDD2",
  };

  #ifdef CONFIG_PM

  static int wm8994_suspend(struct device *dev)

  {
  	struct wm8994 *wm8994 = dev_get_drvdata(dev);
  	int ret;

  	/* Don't actually go through with the suspend if the CODEC is
  	 * still active (eg, for audio passthrough from CP. */
  	ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_1);
  	if (ret < 0) {
  		dev_err(dev, "Failed to read power status: %d
  ", ret);
  	} else if (ret & WM8994_VMID_SEL_MASK) {
  		dev_dbg(dev, "CODEC still active, ignoring suspend
  ");
  		return 0;
  	}

  	ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_4);
  	if (ret < 0) {
  		dev_err(dev, "Failed to read power status: %d
  ", ret);
  	} else if (ret & (WM8994_AIF2ADCL_ENA | WM8994_AIF2ADCR_ENA |
  			  WM8994_AIF1ADC2L_ENA | WM8994_AIF1ADC2R_ENA |
  			  WM8994_AIF1ADC1L_ENA | WM8994_AIF1ADC1R_ENA)) {
  		dev_dbg(dev, "CODEC still active, ignoring suspend
  ");
  		return 0;
  	}
  
  	ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_5);
  	if (ret < 0) {
  		dev_err(dev, "Failed to read power status: %d
  ", ret);
  	} else if (ret & (WM8994_AIF2DACL_ENA | WM8994_AIF2DACR_ENA |
  			  WM8994_AIF1DAC2L_ENA | WM8994_AIF1DAC2R_ENA |
  			  WM8994_AIF1DAC1L_ENA | WM8994_AIF1DAC1R_ENA)) {
  		dev_dbg(dev, "CODEC still active, ignoring suspend
  ");
  		return 0;
  	}
  
  	switch (wm8994->type) {
  	case WM8958:

  	case WM1811:

  		ret = wm8994_reg_read(wm8994, WM8958_MIC_DETECT_1);
  		if (ret < 0) {
  			dev_err(dev, "Failed to read power status: %d
  ", ret);
  		} else if (ret & WM8958_MICD_ENA) {
  			dev_dbg(dev, "CODEC still active, ignoring suspend
  ");
  			return 0;
  		}
  		break;
  	default:
  		break;
  	}

  	switch (wm8994->type) {
  	case WM1811:
  		ret = wm8994_reg_read(wm8994, WM8994_ANTIPOP_2);
  		if (ret < 0) {
  			dev_err(dev, "Failed to read jackdet: %d
  ", ret);
  		} else if (ret & WM1811_JACKDET_MODE_MASK) {
  			dev_dbg(dev, "CODEC still active, ignoring suspend
  ");
  			return 0;
  		}
  		break;
  	default:
  		break;
  	}

  	/* Disable LDO pulldowns while the device is suspended if we
  	 * don't know that something will be driving them. */
  	if (!wm8994->ldo_ena_always_driven)
  		wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
  				WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
  				WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD);

  	/* Explicitly put the device into reset in case regulators
  	 * don't get disabled in order to ensure consistent restart.
  	 */

  	wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET,
  			 wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET));

  	regcache_cache_only(wm8994->regmap, true);

  	regcache_mark_dirty(wm8994->regmap);

  	wm8994->suspended = true;

  	ret = regulator_bulk_disable(wm8994->num_supplies,

  				     wm8994->supplies);
  	if (ret != 0) {
  		dev_err(dev, "Failed to disable supplies: %d
  ", ret);
  		return ret;
  	}
  
  	return 0;
  }

  static int wm8994_resume(struct device *dev)

  {
  	struct wm8994 *wm8994 = dev_get_drvdata(dev);

  	int ret;

  	/* We may have lied to the PM core about suspending */
  	if (!wm8994->suspended)
  		return 0;

  	ret = regulator_bulk_enable(wm8994->num_supplies,

  				    wm8994->supplies);
  	if (ret != 0) {
  		dev_err(dev, "Failed to enable supplies: %d
  ", ret);
  		return ret;
  	}

  	regcache_cache_only(wm8994->regmap, false);

  	ret = regcache_sync(wm8994->regmap);
  	if (ret != 0) {
  		dev_err(dev, "Failed to restore register map: %d
  ", ret);
  		goto err_enable;

  	}

  	/* Disable LDO pulldowns while the device is active */
  	wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
  			WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
  			0);

  	wm8994->suspended = false;

  	return 0;

  
  err_enable:
  	regulator_bulk_disable(wm8994->num_supplies, wm8994->supplies);
  
  	return ret;

  }
  #endif
  
  #ifdef CONFIG_REGULATOR
  static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
  {
  	struct wm8994_ldo_pdata *ldo_pdata;
  
  	if (!pdata)
  		return 0;
  
  	ldo_pdata = &pdata->ldo[ldo];
  
  	if (!ldo_pdata->init_data)
  		return 0;
  
  	return ldo_pdata->init_data->num_consumer_supplies != 0;
  }
  #else
  static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
  {
  	return 0;
  }
  #endif
  
  /*
   * Instantiate the generic non-control parts of the device.
   */

  static int wm8994_device_init(struct wm8994 *wm8994, int irq)

  {
  	struct wm8994_pdata *pdata = wm8994->dev->platform_data;

  	struct regmap_config *regmap_config;

  	const char *devname;

  	int ret, i;

  	int pulls = 0;

  	dev_set_drvdata(wm8994->dev, wm8994);
  
  	/* Add the on-chip regulators first for bootstrapping */
  	ret = mfd_add_devices(wm8994->dev, -1,
  			      wm8994_regulator_devs,
  			      ARRAY_SIZE(wm8994_regulator_devs),
  			      NULL, 0);
  	if (ret != 0) {
  		dev_err(wm8994->dev, "Failed to add children: %d
  ", ret);

  		goto err_regmap;

  	}

  	switch (wm8994->type) {

  	case WM1811:
  		wm8994->num_supplies = ARRAY_SIZE(wm1811_main_supplies);
  		break;

  	case WM8994:
  		wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies);
  		break;
  	case WM8958:
  		wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies);
  		break;
  	default:
  		BUG();

  		goto err_regmap;

  	}

  	wm8994->supplies = devm_kzalloc(wm8994->dev,
  					sizeof(struct regulator_bulk_data) *
  					wm8994->num_supplies, GFP_KERNEL);

  	if (!wm8994->supplies) {
  		ret = -ENOMEM;

  		goto err_regmap;

  	}

  	switch (wm8994->type) {

  	case WM1811:
  		for (i = 0; i < ARRAY_SIZE(wm1811_main_supplies); i++)
  			wm8994->supplies[i].supply = wm1811_main_supplies[i];
  		break;

  	case WM8994:
  		for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
  			wm8994->supplies[i].supply = wm8994_main_supplies[i];
  		break;
  	case WM8958:
  		for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++)
  			wm8994->supplies[i].supply = wm8958_main_supplies[i];
  		break;
  	default:
  		BUG();

  		goto err_regmap;

  	}
  		
  	ret = regulator_bulk_get(wm8994->dev, wm8994->num_supplies,

  				 wm8994->supplies);
  	if (ret != 0) {
  		dev_err(wm8994->dev, "Failed to get supplies: %d
  ", ret);

  		goto err_regmap;

  	}

  	ret = regulator_bulk_enable(wm8994->num_supplies,

  				    wm8994->supplies);
  	if (ret != 0) {
  		dev_err(wm8994->dev, "Failed to enable supplies: %d
  ", ret);

  		goto err_get;

  	}
  
  	ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
  	if (ret < 0) {
  		dev_err(wm8994->dev, "Failed to read ID register
  ");
  		goto err_enable;
  	}

  	switch (ret) {

  	case 0x1811:
  		devname = "WM1811";
  		if (wm8994->type != WM1811)
  			dev_warn(wm8994->dev, "Device registered as type %d
  ",
  				 wm8994->type);
  		wm8994->type = WM1811;
  		break;

  	case 0x8994:
  		devname = "WM8994";
  		if (wm8994->type != WM8994)
  			dev_warn(wm8994->dev, "Device registered as type %d
  ",
  				 wm8994->type);
  		wm8994->type = WM8994;
  		break;
  	case 0x8958:
  		devname = "WM8958";
  		if (wm8994->type != WM8958)
  			dev_warn(wm8994->dev, "Device registered as type %d
  ",
  				 wm8994->type);
  		wm8994->type = WM8958;
  		break;
  	default:

  		dev_err(wm8994->dev, "Device is not a WM8994, ID is %x
  ",
  			ret);
  		ret = -EINVAL;
  		goto err_enable;
  	}
  
  	ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
  	if (ret < 0) {
  		dev_err(wm8994->dev, "Failed to read revision register: %d
  ",
  			ret);
  		goto err_enable;
  	}

  	wm8994->revision = ret;

  	switch (wm8994->type) {
  	case WM8994:

  		switch (wm8994->revision) {

  		case 0:
  		case 1:

  			dev_warn(wm8994->dev,
  				 "revision %c not fully supported
  ",

  				 'A' + wm8994->revision);

  			break;
  		default:
  			break;
  		}

  		break;

  	case WM1811:
  		/* Revision C did not change the relevant layer */

  		if (wm8994->revision > 1)
  			wm8994->revision++;

  		break;

  	default:

  		break;
  	}

  	dev_info(wm8994->dev, "%s revision %c
  ", devname,
  		 'A' + wm8994->revision);

  	switch (wm8994->type) {
  	case WM1811:
  		regmap_config = &wm1811_regmap_config;
  		break;
  	case WM8994:
  		regmap_config = &wm8994_regmap_config;
  		break;
  	case WM8958:
  		regmap_config = &wm8958_regmap_config;
  		break;
  	default:
  		dev_err(wm8994->dev, "Unknown device type %d
  ", wm8994->type);
  		return -EINVAL;
  	}
  
  	ret = regmap_reinit_cache(wm8994->regmap, regmap_config);
  	if (ret != 0) {
  		dev_err(wm8994->dev, "Failed to reinit register cache: %d
  ",
  			ret);
  		return ret;
  	}

  
  	if (pdata) {

  		wm8994->irq_base = pdata->irq_base;

  		wm8994->gpio_base = pdata->gpio_base;
  
  		/* GPIO configuration is only applied if it's non-zero */
  		for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
  			if (pdata->gpio_defaults[i]) {
  				wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
  						0xffff,
  						pdata->gpio_defaults[i]);
  			}
  		}

  
  		wm8994->ldo_ena_always_driven = pdata->ldo_ena_always_driven;

  
  		if (pdata->spkmode_pu)
  			pulls |= WM8994_SPKMODE_PU;

  	}

  	/* Disable unneeded pulls */

  	wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,

  			WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD |
  			WM8994_SPKMODE_PU | WM8994_CSNADDR_PD,
  			pulls);

  	/* In some system designs where the regulators are not in use,
  	 * we can achieve a small reduction in leakage currents by
  	 * floating LDO outputs.  This bit makes no difference if the
  	 * LDOs are enabled, it only affects cases where the LDOs were
  	 * in operation and are then disabled.
  	 */
  	for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
  		if (wm8994_ldo_in_use(pdata, i))
  			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
  					WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
  		else
  			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
  					WM8994_LDO1_DISCH, 0);
  	}

  	wm8994_irq_init(wm8994);

  	ret = mfd_add_devices(wm8994->dev, -1,
  			      wm8994_devs, ARRAY_SIZE(wm8994_devs),
  			      NULL, 0);
  	if (ret != 0) {
  		dev_err(wm8994->dev, "Failed to add children: %d
  ", ret);

  		goto err_irq;

  	}

  	pm_runtime_enable(wm8994->dev);
  	pm_runtime_resume(wm8994->dev);

  	return 0;

  err_irq:
  	wm8994_irq_exit(wm8994);

  err_enable:

  	regulator_bulk_disable(wm8994->num_supplies,

  			       wm8994->supplies);
  err_get:

  	regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);

  err_regmap:
  	regmap_exit(wm8994->regmap);

  	mfd_remove_devices(wm8994->dev);

  	return ret;
  }
  
  static void wm8994_device_exit(struct wm8994 *wm8994)
  {

  	pm_runtime_disable(wm8994->dev);

  	mfd_remove_devices(wm8994->dev);

  	wm8994_irq_exit(wm8994);

  	regulator_bulk_disable(wm8994->num_supplies,

  			       wm8994->supplies);

  	regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);

  	regmap_exit(wm8994->regmap);

  }

  static const struct of_device_id wm8994_of_match[] = {
  	{ .compatible = "wlf,wm1811", },
  	{ .compatible = "wlf,wm8994", },
  	{ .compatible = "wlf,wm8958", },
  	{ }
  };
  MODULE_DEVICE_TABLE(of, wm8994_of_match);

  static int wm8994_i2c_probe(struct i2c_client *i2c,
  			    const struct i2c_device_id *id)
  {
  	struct wm8994 *wm8994;

  	int ret;

  	wm8994 = devm_kzalloc(&i2c->dev, sizeof(struct wm8994), GFP_KERNEL);

  	if (wm8994 == NULL)

  		return -ENOMEM;

  
  	i2c_set_clientdata(i2c, wm8994);
  	wm8994->dev = &i2c->dev;

  	wm8994->irq = i2c->irq;

  	wm8994->type = id->driver_data;

  	wm8994->regmap = regmap_init_i2c(i2c, &wm8994_base_regmap_config);

  	if (IS_ERR(wm8994->regmap)) {
  		ret = PTR_ERR(wm8994->regmap);
  		dev_err(wm8994->dev, "Failed to allocate register map: %d
  ",
  			ret);

  		return ret;
  	}

  	return wm8994_device_init(wm8994, i2c->irq);

  }
  
  static int wm8994_i2c_remove(struct i2c_client *i2c)
  {
  	struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
  
  	wm8994_device_exit(wm8994);
  
  	return 0;
  }

  static const struct i2c_device_id wm8994_i2c_id[] = {

  	{ "wm1811", WM1811 },

  	{ "wm1811a", WM1811 },

  	{ "wm8994", WM8994 },
  	{ "wm8958", WM8958 },

  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);

  static UNIVERSAL_DEV_PM_OPS(wm8994_pm_ops, wm8994_suspend, wm8994_resume,
  			    NULL);

  static struct i2c_driver wm8994_i2c_driver = {
  	.driver = {

  		.name = "wm8994",
  		.owner = THIS_MODULE,
  		.pm = &wm8994_pm_ops,

  		.of_match_table = wm8994_of_match,

  	},
  	.probe = wm8994_i2c_probe,
  	.remove = wm8994_i2c_remove,

  	.id_table = wm8994_i2c_id,
  };
  
  static int __init wm8994_i2c_init(void)
  {
  	int ret;
  
  	ret = i2c_add_driver(&wm8994_i2c_driver);
  	if (ret != 0)
  		pr_err("Failed to register wm8994 I2C driver: %d
  ", ret);
  
  	return ret;
  }
  module_init(wm8994_i2c_init);
  
  static void __exit wm8994_i2c_exit(void)
  {
  	i2c_del_driver(&wm8994_i2c_driver);
  }
  module_exit(wm8994_i2c_exit);
  
  MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");