/*
   * Regulator support for WM8400
   *
   * Copyright 2008 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/bug.h>
  #include <linux/err.h>
  #include <linux/kernel.h>

  #include <linux/module.h>

  #include <linux/regulator/driver.h>
  #include <linux/mfd/wm8400-private.h>
  
  static int wm8400_ldo_is_enabled(struct regulator_dev *dev)
  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	u16 val;
  
  	val = wm8400_reg_read(wm8400, WM8400_LDO1_CONTROL + rdev_get_id(dev));
  	return (val & WM8400_LDO1_ENA) != 0;
  }
  
  static int wm8400_ldo_enable(struct regulator_dev *dev)
  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  
  	return wm8400_set_bits(wm8400, WM8400_LDO1_CONTROL + rdev_get_id(dev),
  			       WM8400_LDO1_ENA, WM8400_LDO1_ENA);
  }
  
  static int wm8400_ldo_disable(struct regulator_dev *dev)
  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  
  	return wm8400_set_bits(wm8400, WM8400_LDO1_CONTROL + rdev_get_id(dev),
  			       WM8400_LDO1_ENA, 0);
  }

  static int wm8400_ldo_list_voltage(struct regulator_dev *dev,
  				   unsigned selector)
  {
  	if (selector > WM8400_LDO1_VSEL_MASK)
  		return -EINVAL;
  
  	if (selector < 15)
  		return 900000 + (selector * 50000);
  	else
  		return 1600000 + ((selector - 14) * 100000);
  }

  static int wm8400_ldo_get_voltage_sel(struct regulator_dev *dev)

  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	u16 val;
  
  	val = wm8400_reg_read(wm8400, WM8400_LDO1_CONTROL + rdev_get_id(dev));
  	val &= WM8400_LDO1_VSEL_MASK;

  	return val;

  }
  
  static int wm8400_ldo_set_voltage(struct regulator_dev *dev,

  				  int min_uV, int max_uV, unsigned *selector)

  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	u16 val;
  
  	if (min_uV < 900000 || min_uV > 3300000)
  		return -EINVAL;
  
  	if (min_uV < 1700000) {
  		/* Steps of 50mV from 900mV;  */
  		val = (min_uV - 850001) / 50000;
  
  		if ((val * 50000) + 900000 > max_uV)
  			return -EINVAL;
  		BUG_ON((val * 50000) + 900000 < min_uV);
  	} else {
  		/* Steps of 100mV from 1700mV */
  		val = ((min_uV - 1600001) / 100000);
  
  		if ((val * 100000) + 1700000 > max_uV)
  			return -EINVAL;
  		BUG_ON((val * 100000) + 1700000 < min_uV);
  
  		val += 0xf;
  	}

  	*selector = val;

  	return wm8400_set_bits(wm8400, WM8400_LDO1_CONTROL + rdev_get_id(dev),
  			       WM8400_LDO1_VSEL_MASK, val);
  }
  
  static struct regulator_ops wm8400_ldo_ops = {
  	.is_enabled = wm8400_ldo_is_enabled,
  	.enable = wm8400_ldo_enable,
  	.disable = wm8400_ldo_disable,

  	.list_voltage = wm8400_ldo_list_voltage,

  	.get_voltage_sel = wm8400_ldo_get_voltage_sel,

  	.set_voltage = wm8400_ldo_set_voltage,
  };
  
  static int wm8400_dcdc_is_enabled(struct regulator_dev *dev)
  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
  	u16 val;
  
  	val = wm8400_reg_read(wm8400, WM8400_DCDC1_CONTROL_1 + offset);
  	return (val & WM8400_DC1_ENA) != 0;
  }
  
  static int wm8400_dcdc_enable(struct regulator_dev *dev)
  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
  
  	return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
  			       WM8400_DC1_ENA, WM8400_DC1_ENA);
  }
  
  static int wm8400_dcdc_disable(struct regulator_dev *dev)
  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
  
  	return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
  			       WM8400_DC1_ENA, 0);
  }

  static int wm8400_dcdc_list_voltage(struct regulator_dev *dev,
  				    unsigned selector)
  {
  	if (selector > WM8400_DC1_VSEL_MASK)
  		return -EINVAL;
  
  	return 850000 + (selector * 25000);
  }

  static int wm8400_dcdc_get_voltage_sel(struct regulator_dev *dev)

  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	u16 val;
  	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
  
  	val = wm8400_reg_read(wm8400, WM8400_DCDC1_CONTROL_1 + offset);
  	val &= WM8400_DC1_VSEL_MASK;

  	return val;

  }
  
  static int wm8400_dcdc_set_voltage(struct regulator_dev *dev,

  				   int min_uV, int max_uV, unsigned *selector)

  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	u16 val;
  	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
  
  	if (min_uV < 850000)
  		return -EINVAL;
  
  	val = (min_uV - 825001) / 25000;
  
  	if (850000 + (25000 * val) > max_uV)
  		return -EINVAL;
  	BUG_ON(850000 + (25000 * val) < min_uV);

  	*selector = val;

  	return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
  			       WM8400_DC1_VSEL_MASK, val);
  }
  
  static unsigned int wm8400_dcdc_get_mode(struct regulator_dev *dev)
  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
  	u16 data[2];
  	int ret;
  
  	ret = wm8400_block_read(wm8400, WM8400_DCDC1_CONTROL_1 + offset, 2,
  				data);
  	if (ret != 0)
  		return 0;
  
  	/* Datasheet: hibernate */
  	if (data[0] & WM8400_DC1_SLEEP)
  		return REGULATOR_MODE_STANDBY;
  
  	/* Datasheet: standby */
  	if (!(data[0] & WM8400_DC1_ACTIVE))
  		return REGULATOR_MODE_IDLE;
  
  	/* Datasheet: active with or without force PWM */
  	if (data[1] & WM8400_DC1_FRC_PWM)
  		return REGULATOR_MODE_FAST;
  	else
  		return REGULATOR_MODE_NORMAL;
  }
  
  static int wm8400_dcdc_set_mode(struct regulator_dev *dev, unsigned int mode)
  {
  	struct wm8400 *wm8400 = rdev_get_drvdata(dev);
  	int offset = (rdev_get_id(dev) - WM8400_DCDC1) * 2;
  	int ret;
  
  	switch (mode) {
  	case REGULATOR_MODE_FAST:
  		/* Datasheet: active with force PWM */
  		ret = wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_2 + offset,
  				      WM8400_DC1_FRC_PWM, WM8400_DC1_FRC_PWM);
  		if (ret != 0)
  			return ret;
  
  		return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
  				       WM8400_DC1_ACTIVE | WM8400_DC1_SLEEP,
  				       WM8400_DC1_ACTIVE);
  
  	case REGULATOR_MODE_NORMAL:
  		/* Datasheet: active */
  		ret = wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_2 + offset,
  				      WM8400_DC1_FRC_PWM, 0);
  		if (ret != 0)
  			return ret;
  
  		return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
  				       WM8400_DC1_ACTIVE | WM8400_DC1_SLEEP,
  				       WM8400_DC1_ACTIVE);
  
  	case REGULATOR_MODE_IDLE:
  		/* Datasheet: standby */
  		ret = wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
  				      WM8400_DC1_ACTIVE, 0);
  		if (ret != 0)
  			return ret;
  		return wm8400_set_bits(wm8400, WM8400_DCDC1_CONTROL_1 + offset,
  				       WM8400_DC1_SLEEP, 0);
  
  	default:
  		return -EINVAL;
  	}
  }
  
  static unsigned int wm8400_dcdc_get_optimum_mode(struct regulator_dev *dev,
  						 int input_uV, int output_uV,
  						 int load_uA)
  {
  	return REGULATOR_MODE_NORMAL;
  }
  
  static struct regulator_ops wm8400_dcdc_ops = {
  	.is_enabled = wm8400_dcdc_is_enabled,
  	.enable = wm8400_dcdc_enable,
  	.disable = wm8400_dcdc_disable,

  	.list_voltage = wm8400_dcdc_list_voltage,

  	.get_voltage_sel = wm8400_dcdc_get_voltage_sel,

  	.set_voltage = wm8400_dcdc_set_voltage,
  	.get_mode = wm8400_dcdc_get_mode,
  	.set_mode = wm8400_dcdc_set_mode,
  	.get_optimum_mode = wm8400_dcdc_get_optimum_mode,
  };
  
  static struct regulator_desc regulators[] = {
  	{
  		.name = "LDO1",
  		.id = WM8400_LDO1,
  		.ops = &wm8400_ldo_ops,

  		.n_voltages = WM8400_LDO1_VSEL_MASK + 1,

  		.type = REGULATOR_VOLTAGE,
  		.owner = THIS_MODULE,
  	},
  	{
  		.name = "LDO2",
  		.id = WM8400_LDO2,
  		.ops = &wm8400_ldo_ops,

  		.n_voltages = WM8400_LDO2_VSEL_MASK + 1,

  		.type = REGULATOR_VOLTAGE,
  		.owner = THIS_MODULE,
  	},
  	{
  		.name = "LDO3",
  		.id = WM8400_LDO3,
  		.ops = &wm8400_ldo_ops,

  		.n_voltages = WM8400_LDO3_VSEL_MASK + 1,

  		.type = REGULATOR_VOLTAGE,
  		.owner = THIS_MODULE,
  	},
  	{
  		.name = "LDO4",
  		.id = WM8400_LDO4,
  		.ops = &wm8400_ldo_ops,

  		.n_voltages = WM8400_LDO4_VSEL_MASK + 1,

  		.type = REGULATOR_VOLTAGE,
  		.owner = THIS_MODULE,
  	},
  	{
  		.name = "DCDC1",
  		.id = WM8400_DCDC1,
  		.ops = &wm8400_dcdc_ops,

  		.n_voltages = WM8400_DC1_VSEL_MASK + 1,

  		.type = REGULATOR_VOLTAGE,
  		.owner = THIS_MODULE,
  	},
  	{
  		.name = "DCDC2",
  		.id = WM8400_DCDC2,
  		.ops = &wm8400_dcdc_ops,

  		.n_voltages = WM8400_DC2_VSEL_MASK + 1,

  		.type = REGULATOR_VOLTAGE,
  		.owner = THIS_MODULE,
  	},
  };

  static int __devinit wm8400_regulator_probe(struct platform_device *pdev)

  {

  	struct wm8400 *wm8400 = container_of(pdev, struct wm8400, regulators[pdev->id]);

  	struct regulator_dev *rdev;
  
  	rdev = regulator_register(&regulators[pdev->id], &pdev->dev,

  				  pdev->dev.platform_data, wm8400, NULL);

  
  	if (IS_ERR(rdev))
  		return PTR_ERR(rdev);

  	platform_set_drvdata(pdev, rdev);

  	return 0;
  }
  
  static int __devexit wm8400_regulator_remove(struct platform_device *pdev)
  {
  	struct regulator_dev *rdev = platform_get_drvdata(pdev);

  	platform_set_drvdata(pdev, NULL);

  	regulator_unregister(rdev);
  
  	return 0;
  }
  
  static struct platform_driver wm8400_regulator_driver = {
  	.driver = {
  		.name = "wm8400-regulator",
  	},
  	.probe = wm8400_regulator_probe,
  	.remove = __devexit_p(wm8400_regulator_remove),
  };
  
  /**
   * wm8400_register_regulator - enable software control of a WM8400 regulator
   *
   * This function enables software control of a WM8400 regulator via
   * the regulator API.  It is intended to be called from the
   * platform_init() callback of the WM8400 MFD driver.
   *
   * @param dev      The WM8400 device to operate on.
   * @param reg      The regulator to control.
   * @param initdata Regulator initdata for the regulator.
   */
  int wm8400_register_regulator(struct device *dev, int reg,
  			      struct regulator_init_data *initdata)
  {

  	struct wm8400 *wm8400 = dev_get_drvdata(dev);

  
  	if (wm8400->regulators[reg].name)
  		return -EBUSY;
  
  	initdata->driver_data = wm8400;
  
  	wm8400->regulators[reg].name = "wm8400-regulator";
  	wm8400->regulators[reg].id = reg;
  	wm8400->regulators[reg].dev.parent = dev;

  	wm8400->regulators[reg].dev.platform_data = initdata;
  
  	return platform_device_register(&wm8400->regulators[reg]);
  }
  EXPORT_SYMBOL_GPL(wm8400_register_regulator);
  
  static int __init wm8400_regulator_init(void)
  {
  	return platform_driver_register(&wm8400_regulator_driver);
  }

  subsys_initcall(wm8400_regulator_init);

  
  static void __exit wm8400_regulator_exit(void)
  {
  	platform_driver_unregister(&wm8400_regulator_driver);
  }
  module_exit(wm8400_regulator_exit);
  
  MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
  MODULE_DESCRIPTION("WM8400 regulator driver");
  MODULE_LICENSE("GPL");
  MODULE_ALIAS("platform:wm8400-regulator");