/*
 * tps80031-regulator.c -- TI TPS80031 regulator driver.
 *
 * Regulator driver for TI TPS80031/TPS80032 Fully Integrated Power
 * Management with Power Path and Battery Charger.
 *
 * Copyright (c) 2012, NVIDIA Corporation.
 *
 * Author: Laxman Dewangan <ldewangan@nvidia.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 version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
 * whether express or implied; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 * 02111-1307, USA
 */

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mfd/tps80031.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/slab.h>

/* Flags for DCDC Voltage reading */
#define DCDC_OFFSET_EN		BIT(0)
#define DCDC_EXTENDED_EN	BIT(1)
#define TRACK_MODE_ENABLE	BIT(2)

#define SMPS_MULTOFFSET_VIO	BIT(1)
#define SMPS_MULTOFFSET_SMPS1	BIT(3)
#define SMPS_MULTOFFSET_SMPS2	BIT(4)
#define SMPS_MULTOFFSET_SMPS3	BIT(6)
#define SMPS_MULTOFFSET_SMPS4	BIT(0)

#define SMPS_CMD_MASK		0xC0
#define SMPS_VSEL_MASK		0x3F
#define LDO_VSEL_MASK		0x1F
#define LDO_TRACK_VSEL_MASK	0x3F

#define MISC2_LDOUSB_IN_VSYS	BIT(4)
#define MISC2_LDOUSB_IN_PMID	BIT(3)
#define MISC2_LDOUSB_IN_MASK	0x18

#define MISC2_LDO3_SEL_VIB_VAL	BIT(0)
#define MISC2_LDO3_SEL_VIB_MASK	0x1

#define BOOST_HW_PWR_EN		BIT(5)
#define BOOST_HW_PWR_EN_MASK	BIT(5)

#define OPA_MODE_EN		BIT(6)
#define OPA_MODE_EN_MASK	BIT(6)

#define USB_VBUS_CTRL_SET	0x04
#define USB_VBUS_CTRL_CLR	0x05
#define VBUS_DISCHRG		0x20

struct tps80031_regulator_info {
	/* Regulator register address.*/
	u8		trans_reg;
	u8		state_reg;
	u8		force_reg;
	u8		volt_reg;
	u8		volt_id;

	/*Power request bits */
	int		preq_bit;

	/* used by regulator core */
	struct regulator_desc	desc;

};

struct tps80031_regulator {
	struct device			*dev;
	struct regulator_dev		*rdev;
	struct tps80031_regulator_info	*rinfo;

	u8				device_flags;
	unsigned int			config_flags;
	unsigned int			ext_ctrl_flag;
};

static inline struct device *to_tps80031_dev(struct regulator_dev *rdev)
{
	return rdev_get_dev(rdev)->parent->parent;
}

static int tps80031_reg_is_enabled(struct regulator_dev *rdev)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);
	u8 reg_val;
	int ret;

	if (ri->ext_ctrl_flag & TPS80031_EXT_PWR_REQ)
		return true;

	ret = tps80031_read(parent, TPS80031_SLAVE_ID1, ri->rinfo->state_reg,
				&reg_val);
	if (ret < 0) {
		dev_err(&rdev->dev, "Reg 0x%02x read failed, err = %d\n",
			ri->rinfo->state_reg, ret);
		return ret;
	}
	return (reg_val & TPS80031_STATE_MASK) == TPS80031_STATE_ON;
}

static int tps80031_reg_enable(struct regulator_dev *rdev)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);
	int ret;

	if (ri->ext_ctrl_flag & TPS80031_EXT_PWR_REQ)
		return 0;

	ret = tps80031_update(parent, TPS80031_SLAVE_ID1, ri->rinfo->state_reg,
			TPS80031_STATE_ON, TPS80031_STATE_MASK);
	if (ret < 0) {
		dev_err(&rdev->dev, "Reg 0x%02x update failed, err = %d\n",
			ri->rinfo->state_reg, ret);
		return ret;
	}
	return ret;
}

static int tps80031_reg_disable(struct regulator_dev *rdev)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);
	int ret;

	if (ri->ext_ctrl_flag & TPS80031_EXT_PWR_REQ)
		return 0;

	ret = tps80031_update(parent, TPS80031_SLAVE_ID1, ri->rinfo->state_reg,
			TPS80031_STATE_OFF, TPS80031_STATE_MASK);
	if (ret < 0)
		dev_err(&rdev->dev, "Reg 0x%02x update failed, err = %d\n",
			ri->rinfo->state_reg, ret);
	return ret;
}

/* DCDC voltages for the selector of 58 to 63 */
static int tps80031_dcdc_voltages[4][5] = {
	{ 1350, 1500, 1800, 1900, 2100},
	{ 1350, 1500, 1800, 1900, 2100},
	{ 2084, 2315, 2778, 2932, 3241},
	{ 4167, 2315, 2778, 2932, 3241},
};

static int tps80031_dcdc_list_voltage(struct regulator_dev *rdev, unsigned sel)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	int volt_index = ri->device_flags & 0x3;

	if (sel == 0)
		return 0;
	else if (sel < 58)
		return regulator_list_voltage_linear(rdev, sel - 1);
	else
		return tps80031_dcdc_voltages[volt_index][sel - 58] * 1000;
}

static int tps80031_dcdc_set_voltage_sel(struct regulator_dev *rdev,
		unsigned vsel)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);
	int ret;
	u8 reg_val;

	if (ri->rinfo->force_reg) {
		ret = tps80031_read(parent, ri->rinfo->volt_id,
						ri->rinfo->force_reg, &reg_val);
		if (ret < 0) {
			dev_err(ri->dev, "reg 0x%02x read failed, e = %d\n",
				ri->rinfo->force_reg, ret);
			return ret;
		}
		if (!(reg_val & SMPS_CMD_MASK)) {
			ret = tps80031_update(parent, ri->rinfo->volt_id,
				ri->rinfo->force_reg, vsel, SMPS_VSEL_MASK);
			if (ret < 0)
				dev_err(ri->dev,
					"reg 0x%02x update failed, e = %d\n",
					ri->rinfo->force_reg, ret);
			return ret;
		}
	}
	ret = tps80031_update(parent, ri->rinfo->volt_id,
			ri->rinfo->volt_reg, vsel, SMPS_VSEL_MASK);
	if (ret < 0)
		dev_err(ri->dev, "reg 0x%02x update failed, e = %d\n",
			ri->rinfo->volt_reg, ret);
	return ret;
}

static int tps80031_dcdc_get_voltage_sel(struct regulator_dev *rdev)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);
	uint8_t vsel = 0;
	int ret;

	if (ri->rinfo->force_reg) {
		ret = tps80031_read(parent, ri->rinfo->volt_id,
						ri->rinfo->force_reg, &vsel);
		if (ret < 0) {
			dev_err(ri->dev, "reg 0x%02x read failed, e = %d\n",
					ri->rinfo->force_reg, ret);
			return ret;
		}

		if (!(vsel & SMPS_CMD_MASK))
			return vsel & SMPS_VSEL_MASK;
	}
	ret = tps80031_read(parent, ri->rinfo->volt_id,
				ri->rinfo->volt_reg, &vsel);
	if (ret < 0) {
		dev_err(ri->dev, "reg 0x%02x read failed, e = %d\n",
			ri->rinfo->volt_reg, ret);
		return ret;
	}
	return vsel & SMPS_VSEL_MASK;
}

static int tps80031_ldo_list_voltage(struct regulator_dev *rdev,
				     unsigned int sel)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);

	/* Check for valid setting for TPS80031 or TPS80032-ES1.0 */
	if ((ri->rinfo->desc.id == TPS80031_REGULATOR_LDO2) &&
			(ri->device_flags & TRACK_MODE_ENABLE)) {
		unsigned nvsel = (sel) & 0x1F;
		if (((tps80031_get_chip_info(parent) == TPS80031) ||
			((tps80031_get_chip_info(parent) == TPS80032) &&
			(tps80031_get_pmu_version(parent) == 0x0))) &&
			((nvsel == 0x0) || (nvsel >= 0x19 && nvsel <= 0x1F))) {
				dev_err(ri->dev,
					"Invalid sel %d in track mode LDO2\n",
					nvsel);
				return -EINVAL;
		}
	}

	return regulator_list_voltage_linear(rdev, sel);
}

static int tps80031_ldo_map_voltage(struct regulator_dev *rdev,
				    int min_uV, int max_uV)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);

	/* Check for valid setting for TPS80031 or TPS80032-ES1.0 */
	if ((ri->rinfo->desc.id == TPS80031_REGULATOR_LDO2) &&
			(ri->device_flags & TRACK_MODE_ENABLE)) {
		if (((tps80031_get_chip_info(parent) == TPS80031) ||
			((tps80031_get_chip_info(parent) == TPS80032) &&
			(tps80031_get_pmu_version(parent) == 0x0)))) {
			return regulator_map_voltage_iterate(rdev, min_uV,
							     max_uV);
		}
	}

	return regulator_map_voltage_linear(rdev, min_uV, max_uV);
}

static int tps80031_vbus_is_enabled(struct regulator_dev *rdev)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);
	int ret = -EIO;
	uint8_t ctrl1 = 0;
	uint8_t ctrl3 = 0;

	ret = tps80031_read(parent, TPS80031_SLAVE_ID2,
			TPS80031_CHARGERUSB_CTRL1, &ctrl1);
	if (ret < 0) {
		dev_err(ri->dev, "reg 0x%02x read failed, e = %d\n",
			TPS80031_CHARGERUSB_CTRL1, ret);
		return ret;
	}
	ret = tps80031_read(parent, TPS80031_SLAVE_ID2,
				TPS80031_CHARGERUSB_CTRL3, &ctrl3);
	if (ret < 0) {
		dev_err(ri->dev, "reg 0x%02x read failed, e = %d\n",
			TPS80031_CHARGERUSB_CTRL3, ret);
		return ret;
	}
	if ((ctrl1 & OPA_MODE_EN) && (ctrl3 & BOOST_HW_PWR_EN))
		return 1;
	return ret;
}

static int tps80031_vbus_enable(struct regulator_dev *rdev)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);
	int ret;

	ret = tps80031_set_bits(parent, TPS80031_SLAVE_ID2,
				TPS80031_CHARGERUSB_CTRL1, OPA_MODE_EN);
	if (ret < 0) {
		dev_err(ri->dev, "reg 0x%02x read failed, e = %d\n",
					TPS80031_CHARGERUSB_CTRL1, ret);
		return ret;
	}

	ret = tps80031_set_bits(parent, TPS80031_SLAVE_ID2,
				TPS80031_CHARGERUSB_CTRL3, BOOST_HW_PWR_EN);
	if (ret < 0) {
		dev_err(ri->dev, "reg 0x%02x read failed, e = %d\n",
			TPS80031_CHARGERUSB_CTRL3, ret);
		return ret;
	}
	return ret;
}

static int tps80031_vbus_disable(struct regulator_dev *rdev)
{
	struct tps80031_regulator *ri = rdev_get_drvdata(rdev);
	struct device *parent = to_tps80031_dev(rdev);
	int ret = 0;

	if (ri->config_flags & TPS80031_VBUS_DISCHRG_EN_PDN) {
		ret = tps80031_write(parent, TPS80031_SLAVE_ID2,
			USB_VBUS_CTRL_SET, VBUS_DISCHRG);
		if (ret < 0) {
			dev_err(ri->dev, "reg 0x%02x write failed, e = %d\n",
				USB_VBUS_CTRL_SET, ret);
			return ret;
		}
	}

	ret = tps80031_clr_bits(parent, TPS80031_SLAVE_ID2,
			TPS80031_CHARGERUSB_CTRL1,  OPA_MODE_EN);
	if (ret < 0) {
		dev_err(ri->dev, "reg 0x%02x clearbit failed, e = %d\n",
				TPS80031_CHARGERUSB_CTRL1, ret);
		return ret;
	}

	ret = tps80031_clr_bits(parent, TPS80031_SLAVE_ID2,
				TPS80031_CHARGERUSB_CTRL3, BOOST_HW_PWR_EN);
	if (ret < 0) {
		dev_err(ri->dev, "reg 0x%02x clearbit failed, e = %d\n",
				TPS80031_CHARGERUSB_CTRL3, ret);
		return ret;
	}

	mdelay(DIV_ROUND_UP(ri->rinfo->desc.enable_time, 1000));
	if (ri->config_flags & TPS80031_VBUS_DISCHRG_EN_PDN) {
		ret = tps80031_write(parent, TPS80031_SLAVE_ID2,
			USB_VBUS_CTRL_CLR, VBUS_DISCHRG);
		if (ret < 0) {
			dev_err(ri->dev, "reg 0x%02x write failed, e = %d\n",
					USB_VBUS_CTRL_CLR, ret);
			return ret;
		}
	}
	return ret;
}

static struct regulator_ops tps80031_dcdc_ops = {
	.list_voltage		= tps80031_dcdc_list_voltage,
	.set_voltage_sel	= tps80031_dcdc_set_voltage_sel,
	.get_voltage_sel	= tps80031_dcdc_get_voltage_sel,
	.enable		= tps80031_reg_enable,
	.disable	= tps80031_reg_disable,
	.is_enabled	= tps80031_reg_is_enabled,
};

static struct regulator_ops tps80031_ldo_ops = {
	.list_voltage		= tps80031_ldo_list_voltage,
	.map_voltage		= tps80031_ldo_map_voltage,
	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
	.enable			= tps80031_reg_enable,
	.disable		= tps80031_reg_disable,
	.is_enabled		= tps80031_reg_is_enabled,
};

static struct regulator_ops tps80031_vbus_sw_ops = {
	.list_voltage	= regulator_list_voltage_linear,
	.enable		= tps80031_vbus_enable,
	.disable	= tps80031_vbus_disable,
	.is_enabled	= tps80031_vbus_is_enabled,
};

static struct regulator_ops tps80031_vbus_hw_ops = {
	.list_voltage	= regulator_list_voltage_linear,
};

static struct regulator_ops tps80031_ext_reg_ops = {
	.list_voltage	= regulator_list_voltage_linear,
	.enable		= tps80031_reg_enable,
	.disable	= tps80031_reg_disable,
	.is_enabled	= tps80031_reg_is_enabled,
};

/* Non-exiting default definition for some register */
#define TPS80031_SMPS3_CFG_FORCE	0
#define TPS80031_SMPS4_CFG_FORCE	0

#define TPS80031_VBUS_CFG_TRANS		0
#define TPS80031_VBUS_CFG_STATE		0

#define TPS80031_REG_SMPS(_id, _volt_id, _pbit)	\
{								\
	.trans_reg = TPS80031_##_id##_CFG_TRANS,		\
	.state_reg = TPS80031_##_id##_CFG_STATE,		\
	.force_reg = TPS80031_##_id##_CFG_FORCE,		\
	.volt_reg = TPS80031_##_id##_CFG_VOLTAGE,		\
	.volt_id = TPS80031_SLAVE_##_volt_id,			\
	.preq_bit = _pbit,					\
	.desc = {						\
		.name = "tps80031_"#_id,			\
		.id = TPS80031_REGULATOR_##_id,			\
		.n_voltages = 63,				\
		.ops = &tps80031_dcdc_ops,			\
		.type = REGULATOR_VOLTAGE,			\
		.owner = THIS_MODULE,				\
		.enable_time = 500,				\
	},							\
}

#define TPS80031_REG_LDO(_id, _preq_bit)			\
{								\
	.trans_reg = TPS80031_##_id##_CFG_TRANS,		\
	.state_reg = TPS80031_##_id##_CFG_STATE,		\
	.volt_reg = TPS80031_##_id##_CFG_VOLTAGE,		\
	.volt_id = TPS80031_SLAVE_ID1,				\
	.preq_bit = _preq_bit,					\
	.desc = {						\
		.owner = THIS_MODULE,				\
		.name = "tps80031_"#_id,			\
		.id = TPS80031_REGULATOR_##_id,			\
		.ops = &tps80031_ldo_ops,			\
		.type = REGULATOR_VOLTAGE,			\
		.min_uV = 1000000,				\
		.uV_step = 100000,				\
		.linear_min_sel = 1,				\
		.n_voltages = 25,				\
		.vsel_reg = TPS80031_##_id##_CFG_VOLTAGE,	\
		.vsel_mask = LDO_VSEL_MASK,			\
		.enable_time = 500,				\
	},							\
}

#define TPS80031_REG_FIXED(_id, max_mV, _ops, _delay, _pbit)	\
{								\
	.trans_reg = TPS80031_##_id##_CFG_TRANS,		\
	.state_reg = TPS80031_##_id##_CFG_STATE,		\
	.volt_id = TPS80031_SLAVE_ID1,				\
	.preq_bit = _pbit,					\
	.desc = {						\
		.name = "tps80031_"#_id,			\
		.id = TPS80031_REGULATOR_##_id,			\
		.min_uV = max_mV * 1000,			\
		.n_voltages = 1,				\
		.ops = &_ops,					\
		.type = REGULATOR_VOLTAGE,			\
		.owner = THIS_MODULE,				\
		.enable_time = _delay,				\
	},							\
}

static struct tps80031_regulator_info tps80031_rinfo[TPS80031_REGULATOR_MAX] = {
	TPS80031_REG_SMPS(VIO,   ID0, 4),
	TPS80031_REG_SMPS(SMPS1, ID0, 0),
	TPS80031_REG_SMPS(SMPS2, ID0, 1),
	TPS80031_REG_SMPS(SMPS3, ID1, 2),
	TPS80031_REG_SMPS(SMPS4, ID1, 3),
	TPS80031_REG_LDO(VANA,   -1),
	TPS80031_REG_LDO(LDO1,   8),
	TPS80031_REG_LDO(LDO2,   9),
	TPS80031_REG_LDO(LDO3,   10),
	TPS80031_REG_LDO(LDO4,   11),
	TPS80031_REG_LDO(LDO5,   12),
	TPS80031_REG_LDO(LDO6,   13),
	TPS80031_REG_LDO(LDO7,   14),
	TPS80031_REG_LDO(LDOLN,  15),
	TPS80031_REG_LDO(LDOUSB, 5),
	TPS80031_REG_FIXED(VBUS,   5000, tps80031_vbus_hw_ops, 100000, -1),
	TPS80031_REG_FIXED(REGEN1, 3300, tps80031_ext_reg_ops, 0, 16),
	TPS80031_REG_FIXED(REGEN2, 3300, tps80031_ext_reg_ops, 0, 17),
	TPS80031_REG_FIXED(SYSEN,  3300, tps80031_ext_reg_ops, 0, 18),
};

static int tps80031_power_req_config(struct device *parent,
		struct tps80031_regulator *ri,
		struct tps80031_regulator_platform_data *tps80031_pdata)
{
	int ret = 0;

	if (ri->rinfo->preq_bit < 0)
		goto skip_pwr_req_config;

	ret = tps80031_ext_power_req_config(parent, ri->ext_ctrl_flag,
			ri->rinfo->preq_bit, ri->rinfo->state_reg,
			ri->rinfo->trans_reg);
	if (ret < 0) {
		dev_err(ri->dev, "ext powerreq config failed, err = %d\n", ret);
		return ret;
	}

skip_pwr_req_config:
	if (tps80031_pdata->ext_ctrl_flag & TPS80031_PWR_ON_ON_SLEEP) {
		ret = tps80031_update(parent, TPS80031_SLAVE_ID1,
				ri->rinfo->trans_reg, TPS80031_TRANS_SLEEP_ON,
				TPS80031_TRANS_SLEEP_MASK);
		if (ret < 0) {
			dev_err(ri->dev, "Reg 0x%02x update failed, e %d\n",
					ri->rinfo->trans_reg, ret);
			return ret;
		}
	}
	return ret;
}

static int tps80031_regulator_config(struct device *parent,
		struct tps80031_regulator *ri,
		struct tps80031_regulator_platform_data *tps80031_pdata)
{
	int ret = 0;

	switch (ri->rinfo->desc.id) {
	case TPS80031_REGULATOR_LDOUSB:
		if (ri->config_flags & (TPS80031_USBLDO_INPUT_VSYS |
			TPS80031_USBLDO_INPUT_PMID)) {
			unsigned val = 0;
			if (ri->config_flags & TPS80031_USBLDO_INPUT_VSYS)
				val = MISC2_LDOUSB_IN_VSYS;
			else
				val = MISC2_LDOUSB_IN_PMID;

			ret = tps80031_update(parent, TPS80031_SLAVE_ID1,
				TPS80031_MISC2, val,
				MISC2_LDOUSB_IN_MASK);
			if (ret < 0) {
				dev_err(ri->dev,
					"LDOUSB config failed, e= %d\n", ret);
				return ret;
			}
		}
		break;

	case TPS80031_REGULATOR_LDO3:
		if (ri->config_flags & TPS80031_LDO3_OUTPUT_VIB) {
			ret = tps80031_update(parent, TPS80031_SLAVE_ID1,
				TPS80031_MISC2, MISC2_LDO3_SEL_VIB_VAL,
				MISC2_LDO3_SEL_VIB_MASK);
			if (ret < 0) {
				dev_err(ri->dev,
					"LDO3 config failed, e = %d\n", ret);
				return ret;
			}
		}
		break;

	case TPS80031_REGULATOR_VBUS:
		/* Provide SW control Ops if VBUS is SW control */
		if (!(ri->config_flags & TPS80031_VBUS_SW_ONLY))
			ri->rinfo->desc.ops = &tps80031_vbus_sw_ops;
		break;
	default:
		break;
	}

	/* Configure Active state to ON, SLEEP to OFF and OFF_state to OFF */
	ret = tps80031_update(parent, TPS80031_SLAVE_ID1, ri->rinfo->trans_reg,
		TPS80031_TRANS_ACTIVE_ON | TPS80031_TRANS_SLEEP_OFF |
		TPS80031_TRANS_OFF_OFF, TPS80031_TRANS_ACTIVE_MASK |
		TPS80031_TRANS_SLEEP_MASK | TPS80031_TRANS_OFF_MASK);
	if (ret < 0) {
		dev_err(ri->dev, "trans reg update failed, e %d\n", ret);
		return ret;
	}

	return ret;
}

static int check_smps_mode_mult(struct device *parent,
	struct tps80031_regulator *ri)
{
	int mult_offset;
	int ret;
	u8 smps_offset;
	u8 smps_mult;

	ret = tps80031_read(parent, TPS80031_SLAVE_ID1,
			TPS80031_SMPS_OFFSET, &smps_offset);
	if (ret < 0) {
		dev_err(parent, "Error in reading smps offset register\n");
		return ret;
	}

	ret = tps80031_read(parent, TPS80031_SLAVE_ID1,
			TPS80031_SMPS_MULT, &smps_mult);
	if (ret < 0) {
		dev_err(parent, "Error in reading smps mult register\n");
		return ret;
	}

	switch (ri->rinfo->desc.id) {
	case TPS80031_REGULATOR_VIO:
		mult_offset = SMPS_MULTOFFSET_VIO;
		break;
	case TPS80031_REGULATOR_SMPS1:
		mult_offset = SMPS_MULTOFFSET_SMPS1;
		break;
	case TPS80031_REGULATOR_SMPS2:
		mult_offset = SMPS_MULTOFFSET_SMPS2;
		break;
	case TPS80031_REGULATOR_SMPS3:
		mult_offset = SMPS_MULTOFFSET_SMPS3;
		break;
	case TPS80031_REGULATOR_SMPS4:
		mult_offset = SMPS_MULTOFFSET_SMPS4;
		break;
	case TPS80031_REGULATOR_LDO2:
		ri->device_flags = smps_mult & BIT(5) ? TRACK_MODE_ENABLE : 0;
		/* TRACK mode the ldo2 varies from 600mV to 1300mV */
		if (ri->device_flags & TRACK_MODE_ENABLE) {
			ri->rinfo->desc.min_uV = 600000;
			ri->rinfo->desc.uV_step = 12500;
			ri->rinfo->desc.n_voltages = 57;
			ri->rinfo->desc.vsel_mask = LDO_TRACK_VSEL_MASK;
		}
		return 0;
	default:
		return 0;
	}

	ri->device_flags = (smps_offset & mult_offset) ? DCDC_OFFSET_EN : 0;
	ri->device_flags |= (smps_mult & mult_offset) ? DCDC_EXTENDED_EN : 0;
	switch (ri->device_flags) {
	case 0:
		ri->rinfo->desc.min_uV = 607700;
		ri->rinfo->desc.uV_step = 12660;
		break;
	case DCDC_OFFSET_EN:
		ri->rinfo->desc.min_uV = 700000;
		ri->rinfo->desc.uV_step = 12500;
		break;
	case DCDC_EXTENDED_EN:
		ri->rinfo->desc.min_uV = 1852000;
		ri->rinfo->desc.uV_step = 38600;
		break;
	case DCDC_OFFSET_EN | DCDC_EXTENDED_EN:
		ri->rinfo->desc.min_uV = 2161000;
		ri->rinfo->desc.uV_step = 38600;
		break;
	}
	return 0;
}

static int tps80031_regulator_probe(struct platform_device *pdev)
{
	struct tps80031_platform_data *pdata;
	struct tps80031_regulator_platform_data *tps_pdata;
	struct tps80031_regulator *ri;
	struct tps80031_regulator *pmic;
	struct regulator_dev *rdev;
	struct regulator_config config = { };
	struct tps80031 *tps80031_mfd = dev_get_drvdata(pdev->dev.parent);
	int ret;
	int num;

	pdata = dev_get_platdata(pdev->dev.parent);

	if (!pdata) {
		dev_err(&pdev->dev, "No platform data\n");
		return -EINVAL;
	}

	pmic = devm_kzalloc(&pdev->dev,
			TPS80031_REGULATOR_MAX * sizeof(*pmic), GFP_KERNEL);
	if (!pmic)
		return -ENOMEM;

	for (num = 0; num < TPS80031_REGULATOR_MAX; ++num) {
		tps_pdata = pdata->regulator_pdata[num];
		ri = &pmic[num];
		ri->rinfo = &tps80031_rinfo[num];
		ri->dev = &pdev->dev;

		check_smps_mode_mult(pdev->dev.parent, ri);
		config.dev = &pdev->dev;
		config.init_data = NULL;
		config.driver_data = ri;
		config.regmap = tps80031_mfd->regmap[ri->rinfo->volt_id];

		if (tps_pdata) {
			config.init_data = tps_pdata->reg_init_data;
			ri->config_flags = tps_pdata->config_flags;
			ri->ext_ctrl_flag = tps_pdata->ext_ctrl_flag;
			ret = tps80031_regulator_config(pdev->dev.parent,
					ri, tps_pdata);
			if (ret < 0) {
				dev_err(&pdev->dev,
					"regulator config failed, e %d\n", ret);
				return ret;
			}

			ret = tps80031_power_req_config(pdev->dev.parent,
					ri, tps_pdata);
			if (ret < 0) {
				dev_err(&pdev->dev,
					"pwr_req config failed, err %d\n", ret);
				return ret;
			}
		}
		rdev = devm_regulator_register(&pdev->dev, &ri->rinfo->desc,
					       &config);
		if (IS_ERR(rdev)) {
			dev_err(&pdev->dev,
				"register regulator failed %s\n",
					ri->rinfo->desc.name);
			return PTR_ERR(rdev);
		}
		ri->rdev = rdev;
	}

	platform_set_drvdata(pdev, pmic);
	return 0;
}

static struct platform_driver tps80031_regulator_driver = {
	.driver	= {
		.name	= "tps80031-pmic",
	},
	.probe		= tps80031_regulator_probe,
};

static int __init tps80031_regulator_init(void)
{
	return platform_driver_register(&tps80031_regulator_driver);
}
subsys_initcall(tps80031_regulator_init);

static void __exit tps80031_regulator_exit(void)
{
	platform_driver_unregister(&tps80031_regulator_driver);
}
module_exit(tps80031_regulator_exit);

MODULE_ALIAS("platform:tps80031-regulator");
MODULE_DESCRIPTION("Regulator Driver for TI TPS80031/TPS80032 PMIC");
MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
MODULE_LICENSE("GPL v2");