/*
 * tps65218-regulator.c
 *
 * Regulator driver for TPS65218 PMIC
 *
 * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.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.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether expressed or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License version 2 for more details.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/mfd/tps65218.h>

#define TPS65218_REGULATOR(_name, _of, _id, _type, _ops, _n, _vr, _vm, _er, \
			   _em, _cr, _cm, _lr, _nlr, _delay, _fuv, _sr, _sm) \
	{							\
		.name			= _name,		\
		.of_match		= _of,			\
		.id			= _id,			\
		.ops			= &_ops,		\
		.n_voltages		= _n,			\
		.type			= _type,	\
		.owner			= THIS_MODULE,		\
		.vsel_reg		= _vr,			\
		.vsel_mask		= _vm,			\
		.csel_reg		= _cr,			\
		.csel_mask		= _cm,			\
		.enable_reg		= _er,			\
		.enable_mask		= _em,			\
		.volt_table		= NULL,			\
		.linear_ranges		= _lr,			\
		.n_linear_ranges	= _nlr,			\
		.ramp_delay		= _delay,		\
		.fixed_uV		= _fuv,			\
		.bypass_reg	= _sr,				\
		.bypass_mask	= _sm,				\
	}							\

static const struct regulator_linear_range dcdc1_dcdc2_ranges[] = {
	REGULATOR_LINEAR_RANGE(850000, 0x0, 0x32, 10000),
	REGULATOR_LINEAR_RANGE(1375000, 0x33, 0x3f, 25000),
};

static const struct regulator_linear_range ldo1_dcdc3_ranges[] = {
	REGULATOR_LINEAR_RANGE(900000, 0x0, 0x1a, 25000),
	REGULATOR_LINEAR_RANGE(1600000, 0x1b, 0x3f, 50000),
};

static const struct regulator_linear_range dcdc4_ranges[] = {
	REGULATOR_LINEAR_RANGE(1175000, 0x0, 0xf, 25000),
	REGULATOR_LINEAR_RANGE(1600000, 0x10, 0x34, 50000),
};

static int tps65218_pmic_set_voltage_sel(struct regulator_dev *dev,
					 unsigned selector)
{
	int ret;
	struct tps65218 *tps = rdev_get_drvdata(dev);
	unsigned int rid = rdev_get_id(dev);

	/* Set the voltage based on vsel value and write protect level is 2 */
	ret = tps65218_set_bits(tps, dev->desc->vsel_reg, dev->desc->vsel_mask,
				selector, TPS65218_PROTECT_L1);

	/* Set GO bit for DCDC1/2 to initiate voltage transistion */
	switch (rid) {
	case TPS65218_DCDC_1:
	case TPS65218_DCDC_2:
		ret = tps65218_set_bits(tps, TPS65218_REG_CONTRL_SLEW_RATE,
					TPS65218_SLEW_RATE_GO,
					TPS65218_SLEW_RATE_GO,
					TPS65218_PROTECT_L1);
		break;
	}

	return ret;
}

static int tps65218_pmic_enable(struct regulator_dev *dev)
{
	struct tps65218 *tps = rdev_get_drvdata(dev);
	int rid = rdev_get_id(dev);

	if (rid < TPS65218_DCDC_1 || rid > TPS65218_LDO_1)
		return -EINVAL;

	/* Enable the regulator and password protection is level 1 */
	return tps65218_set_bits(tps, dev->desc->enable_reg,
				 dev->desc->enable_mask, dev->desc->enable_mask,
				 TPS65218_PROTECT_L1);
}

static int tps65218_pmic_disable(struct regulator_dev *dev)
{
	struct tps65218 *tps = rdev_get_drvdata(dev);
	int rid = rdev_get_id(dev);

	if (rid < TPS65218_DCDC_1 || rid > TPS65218_LDO_1)
		return -EINVAL;

	/* Disable the regulator and password protection is level 1 */
	return tps65218_clear_bits(tps, dev->desc->enable_reg,
				   dev->desc->enable_mask, TPS65218_PROTECT_L1);
}

static int tps65218_pmic_set_suspend_enable(struct regulator_dev *dev)
{
	struct tps65218 *tps = rdev_get_drvdata(dev);
	unsigned int rid = rdev_get_id(dev);

	if (rid < TPS65218_DCDC_1 || rid > TPS65218_LDO_1)
		return -EINVAL;

	return tps65218_clear_bits(tps, dev->desc->bypass_reg,
				   dev->desc->bypass_mask,
				   TPS65218_PROTECT_L1);
}

static int tps65218_pmic_set_suspend_disable(struct regulator_dev *dev)
{
	struct tps65218 *tps = rdev_get_drvdata(dev);
	unsigned int rid = rdev_get_id(dev);

	if (rid < TPS65218_DCDC_1 || rid > TPS65218_LDO_1)
		return -EINVAL;

	/*
	 * Certain revisions of TPS65218 will need to have DCDC3 regulator
	 * enabled always, otherwise an immediate system reboot will occur
	 * during poweroff.
	 */
	if (rid == TPS65218_DCDC_3 && tps->rev == TPS65218_REV_2_1)
		return 0;

	if (!tps->strobes[rid]) {
		if (rid == TPS65218_DCDC_3)
			tps->strobes[rid] = 3;
		else
			return -EINVAL;
	}

	return tps65218_set_bits(tps, dev->desc->bypass_reg,
				 dev->desc->bypass_mask,
				 tps->strobes[rid], TPS65218_PROTECT_L1);
}

/* Operations permitted on DCDC1, DCDC2 */
static struct regulator_ops tps65218_dcdc12_ops = {
	.is_enabled		= regulator_is_enabled_regmap,
	.enable			= tps65218_pmic_enable,
	.disable		= tps65218_pmic_disable,
	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
	.set_voltage_sel	= tps65218_pmic_set_voltage_sel,
	.list_voltage		= regulator_list_voltage_linear_range,
	.map_voltage		= regulator_map_voltage_linear_range,
	.set_voltage_time_sel	= regulator_set_voltage_time_sel,
	.set_suspend_enable	= tps65218_pmic_set_suspend_enable,
	.set_suspend_disable	= tps65218_pmic_set_suspend_disable,
};

/* Operations permitted on DCDC3, DCDC4 and LDO1 */
static struct regulator_ops tps65218_ldo1_dcdc34_ops = {
	.is_enabled		= regulator_is_enabled_regmap,
	.enable			= tps65218_pmic_enable,
	.disable		= tps65218_pmic_disable,
	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
	.set_voltage_sel	= tps65218_pmic_set_voltage_sel,
	.list_voltage		= regulator_list_voltage_linear_range,
	.map_voltage		= regulator_map_voltage_linear_range,
	.set_suspend_enable	= tps65218_pmic_set_suspend_enable,
	.set_suspend_disable	= tps65218_pmic_set_suspend_disable,
};

static const int ls3_currents[] = { 100000, 200000, 500000, 1000000 };


static int tps65218_pmic_set_input_current_lim(struct regulator_dev *dev,
					       int lim_uA)
{
	unsigned int index = 0;
	unsigned int num_currents = ARRAY_SIZE(ls3_currents);
	struct tps65218 *tps = rdev_get_drvdata(dev);

	while (index < num_currents && ls3_currents[index] != lim_uA)
		index++;

	if (index == num_currents)
		return -EINVAL;

	return tps65218_set_bits(tps, dev->desc->csel_reg, dev->desc->csel_mask,
				 index << __builtin_ctz(dev->desc->csel_mask),
				 TPS65218_PROTECT_L1);
}

static int tps65218_pmic_set_current_limit(struct regulator_dev *dev,
					   int min_uA, int max_uA)
{
	int index = 0;
	unsigned int num_currents = ARRAY_SIZE(ls3_currents);
	struct tps65218 *tps = rdev_get_drvdata(dev);

	while (index < num_currents && ls3_currents[index] <= max_uA)
		index++;

	index--;

	if (index < 0 || ls3_currents[index] < min_uA)
		return -EINVAL;

	return tps65218_set_bits(tps, dev->desc->csel_reg, dev->desc->csel_mask,
				 index << __builtin_ctz(dev->desc->csel_mask),
				 TPS65218_PROTECT_L1);
}

static int tps65218_pmic_get_current_limit(struct regulator_dev *dev)
{
	int retval;
	unsigned int index;
	struct tps65218 *tps = rdev_get_drvdata(dev);

	retval = regmap_read(tps->regmap, dev->desc->csel_reg, &index);
	if (retval < 0)
		return retval;

	index = (index & dev->desc->csel_mask) >>
					 __builtin_ctz(dev->desc->csel_mask);

	return ls3_currents[index];
}

static struct regulator_ops tps65218_ls23_ops = {
	.is_enabled		= regulator_is_enabled_regmap,
	.enable			= tps65218_pmic_enable,
	.disable		= tps65218_pmic_disable,
	.set_input_current_limit = tps65218_pmic_set_input_current_lim,
	.set_current_limit	= tps65218_pmic_set_current_limit,
	.get_current_limit	= tps65218_pmic_get_current_limit,
};

/* Operations permitted on DCDC5, DCDC6 */
static struct regulator_ops tps65218_dcdc56_pmic_ops = {
	.is_enabled		= regulator_is_enabled_regmap,
	.enable			= tps65218_pmic_enable,
	.disable		= tps65218_pmic_disable,
	.set_suspend_enable	= tps65218_pmic_set_suspend_enable,
	.set_suspend_disable	= tps65218_pmic_set_suspend_disable,
};

static const struct regulator_desc regulators[] = {
	TPS65218_REGULATOR("DCDC1", "regulator-dcdc1", TPS65218_DCDC_1,
			   REGULATOR_VOLTAGE, tps65218_dcdc12_ops, 64,
			   TPS65218_REG_CONTROL_DCDC1,
			   TPS65218_CONTROL_DCDC1_MASK, TPS65218_REG_ENABLE1,
			   TPS65218_ENABLE1_DC1_EN, 0, 0, dcdc1_dcdc2_ranges,
			   2, 4000, 0, TPS65218_REG_SEQ3,
			   TPS65218_SEQ3_DC1_SEQ_MASK),
	TPS65218_REGULATOR("DCDC2", "regulator-dcdc2", TPS65218_DCDC_2,
			   REGULATOR_VOLTAGE, tps65218_dcdc12_ops, 64,
			   TPS65218_REG_CONTROL_DCDC2,
			   TPS65218_CONTROL_DCDC2_MASK, TPS65218_REG_ENABLE1,
			   TPS65218_ENABLE1_DC2_EN, 0, 0, dcdc1_dcdc2_ranges,
			   2, 4000, 0, TPS65218_REG_SEQ3,
			   TPS65218_SEQ3_DC2_SEQ_MASK),
	TPS65218_REGULATOR("DCDC3", "regulator-dcdc3", TPS65218_DCDC_3,
			   REGULATOR_VOLTAGE, tps65218_ldo1_dcdc34_ops, 64,
			   TPS65218_REG_CONTROL_DCDC3,
			   TPS65218_CONTROL_DCDC3_MASK, TPS65218_REG_ENABLE1,
			   TPS65218_ENABLE1_DC3_EN, 0, 0, ldo1_dcdc3_ranges, 2,
			   0, 0, TPS65218_REG_SEQ4, TPS65218_SEQ4_DC3_SEQ_MASK),
	TPS65218_REGULATOR("DCDC4", "regulator-dcdc4", TPS65218_DCDC_4,
			   REGULATOR_VOLTAGE, tps65218_ldo1_dcdc34_ops, 53,
			   TPS65218_REG_CONTROL_DCDC4,
			   TPS65218_CONTROL_DCDC4_MASK, TPS65218_REG_ENABLE1,
			   TPS65218_ENABLE1_DC4_EN, 0, 0, dcdc4_ranges, 2,
			   0, 0, TPS65218_REG_SEQ4, TPS65218_SEQ4_DC4_SEQ_MASK),
	TPS65218_REGULATOR("DCDC5", "regulator-dcdc5", TPS65218_DCDC_5,
			   REGULATOR_VOLTAGE, tps65218_dcdc56_pmic_ops, 1, -1,
			   -1, TPS65218_REG_ENABLE1, TPS65218_ENABLE1_DC5_EN, 0,
			   0, NULL, 0, 0, 1000000, TPS65218_REG_SEQ5,
			   TPS65218_SEQ5_DC5_SEQ_MASK),
	TPS65218_REGULATOR("DCDC6", "regulator-dcdc6", TPS65218_DCDC_6,
			   REGULATOR_VOLTAGE, tps65218_dcdc56_pmic_ops, 1, -1,
			   -1, TPS65218_REG_ENABLE1, TPS65218_ENABLE1_DC6_EN, 0,
			   0, NULL, 0, 0, 1800000, TPS65218_REG_SEQ5,
			   TPS65218_SEQ5_DC6_SEQ_MASK),
	TPS65218_REGULATOR("LDO1", "regulator-ldo1", TPS65218_LDO_1,
			   REGULATOR_VOLTAGE, tps65218_ldo1_dcdc34_ops, 64,
			   TPS65218_REG_CONTROL_LDO1,
			   TPS65218_CONTROL_LDO1_MASK, TPS65218_REG_ENABLE2,
			   TPS65218_ENABLE2_LDO1_EN, 0, 0, ldo1_dcdc3_ranges,
			   2, 0, 0, TPS65218_REG_SEQ6,
			   TPS65218_SEQ6_LDO1_SEQ_MASK),
	TPS65218_REGULATOR("LS2", "regulator-ls2", TPS65218_LS_2,
			   REGULATOR_CURRENT, tps65218_ls23_ops, 0, 0, 0,
			   TPS65218_REG_ENABLE2, TPS65218_ENABLE2_LS2_EN,
			   TPS65218_REG_CONFIG2, TPS65218_CONFIG2_LS2ILIM_MASK,
			   NULL, 0, 0, 0, 0, 0),
	TPS65218_REGULATOR("LS3", "regulator-ls3", TPS65218_LS_3,
			   REGULATOR_CURRENT, tps65218_ls23_ops, 0, 0, 0,
			   TPS65218_REG_ENABLE2, TPS65218_ENABLE2_LS3_EN,
			   TPS65218_REG_CONFIG2, TPS65218_CONFIG2_LS3ILIM_MASK,
			   NULL, 0, 0, 0, 0, 0),
};

static int tps65218_regulator_probe(struct platform_device *pdev)
{
	struct tps65218 *tps = dev_get_drvdata(pdev->dev.parent);
	struct regulator_dev *rdev;
	struct regulator_config config = { };
	int i, ret;
	unsigned int val;

	config.dev = &pdev->dev;
	config.dev->of_node = tps->dev->of_node;
	config.driver_data = tps;
	config.regmap = tps->regmap;

	/* Allocate memory for strobes */
	tps->strobes = devm_kcalloc(&pdev->dev,
				    TPS65218_NUM_REGULATOR, sizeof(u8),
				    GFP_KERNEL);
	if (!tps->strobes)
		return -ENOMEM;

	for (i = 0; i < ARRAY_SIZE(regulators); i++) {
		rdev = devm_regulator_register(&pdev->dev, &regulators[i],
					       &config);
		if (IS_ERR(rdev)) {
			dev_err(tps->dev, "failed to register %s regulator\n",
				pdev->name);
			return PTR_ERR(rdev);
		}

		ret = regmap_read(tps->regmap, regulators[i].bypass_reg, &val);
		if (ret)
			return ret;

		tps->strobes[i] = val & regulators[i].bypass_mask;
	}

	return 0;
}

static const struct platform_device_id tps65218_regulator_id_table[] = {
	{ "tps65218-regulator", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, tps65218_regulator_id_table);

static struct platform_driver tps65218_regulator_driver = {
	.driver = {
		.name = "tps65218-pmic",
	},
	.probe = tps65218_regulator_probe,
	.id_table = tps65218_regulator_id_table,
};

module_platform_driver(tps65218_regulator_driver);

MODULE_AUTHOR("J Keerthy <j-keerthy@ti.com>");
MODULE_DESCRIPTION("TPS65218 voltage regulator driver");
MODULE_ALIAS("platform:tps65218-pmic");
MODULE_LICENSE("GPL v2");