/*
 * Device driver for regulators in Hi6421V530 IC
 *
 * Copyright (c) <2017> HiSilicon Technologies Co., Ltd.
 *              http://www.hisilicon.com
 * Copyright (c) <2017> Linaro Ltd.
 *              http://www.linaro.org
 *
 * Author: Wang Xiaoyin <hw.wangxiaoyin@hisilicon.com>
 *         Guodong Xu <guodong.xu@linaro.org>
 *
 * 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/mfd/hi6421-pmic.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>

/*
 * struct hi6421v530_regulator_info - hi6421v530 regulator information
 * @desc: regulator description
 * @mode_mask: ECO mode bitmask of LDOs; for BUCKs, this masks sleep
 * @eco_microamp: eco mode load upper limit (in uA), valid for LDOs only
 */
struct hi6421v530_regulator_info {
	struct regulator_desc rdesc;
	u8 mode_mask;
	u32 eco_microamp;
};

/* HI6421v530 regulators */
enum hi6421v530_regulator_id {
	HI6421V530_LDO3,
	HI6421V530_LDO9,
	HI6421V530_LDO11,
	HI6421V530_LDO15,
	HI6421V530_LDO16,
};

static const unsigned int ldo_3_voltages[] = {
	1800000, 1825000, 1850000, 1875000,
	1900000, 1925000, 1950000, 1975000,
	2000000, 2025000, 2050000, 2075000,
	2100000, 2125000, 2150000, 2200000,
};

static const unsigned int ldo_9_11_voltages[] = {
	1750000, 1800000, 1825000, 2800000,
	2850000, 2950000, 3000000, 3300000,
};

static const unsigned int ldo_15_16_voltages[] = {
	1750000, 1800000, 2400000, 2600000,
	2700000, 2850000, 2950000, 3000000,
};

static const struct regulator_ops hi6421v530_ldo_ops;

#define HI6421V530_LDO_ENABLE_TIME (350)

/*
 * _id - LDO id name string
 * v_table - voltage table
 * vreg - voltage select register
 * vmask - voltage select mask
 * ereg - enable register
 * emask - enable mask
 * odelay - off/on delay time in uS
 * ecomask - eco mode mask
 * ecoamp - eco mode load uppler limit in uA
 */
#define HI6421V530_LDO(_ID, v_table, vreg, vmask, ereg, emask,		\
		   odelay, ecomask, ecoamp) {				\
	.rdesc = {							\
		.name		 = #_ID,				\
		.of_match        = of_match_ptr(#_ID),			\
		.regulators_node = of_match_ptr("regulators"),		\
		.ops		 = &hi6421v530_ldo_ops,			\
		.type		 = REGULATOR_VOLTAGE,			\
		.id		 = HI6421V530_##_ID,			\
		.owner		 = THIS_MODULE,				\
		.n_voltages	 = ARRAY_SIZE(v_table),			\
		.volt_table	 = v_table,				\
		.vsel_reg	 = HI6421_REG_TO_BUS_ADDR(vreg),	\
		.vsel_mask	 = vmask,				\
		.enable_reg	 = HI6421_REG_TO_BUS_ADDR(ereg),	\
		.enable_mask	 = emask,				\
		.enable_time	 = HI6421V530_LDO_ENABLE_TIME,		\
		.off_on_delay	 = odelay,				\
	},								\
	.mode_mask	= ecomask,					\
	.eco_microamp	= ecoamp,					\
}

/* HI6421V530 regulator information */

static struct hi6421v530_regulator_info hi6421v530_regulator_info[] = {
	HI6421V530_LDO(LDO3, ldo_3_voltages, 0x061, 0xf, 0x060, 0x2,
		   20000, 0x6, 8000),
	HI6421V530_LDO(LDO9, ldo_9_11_voltages, 0x06b, 0x7, 0x06a, 0x2,
		   40000, 0x6, 8000),
	HI6421V530_LDO(LDO11, ldo_9_11_voltages, 0x06f, 0x7, 0x06e, 0x2,
		   40000, 0x6, 8000),
	HI6421V530_LDO(LDO15, ldo_15_16_voltages, 0x077, 0x7, 0x076, 0x2,
		   40000, 0x6, 8000),
	HI6421V530_LDO(LDO16, ldo_15_16_voltages, 0x079, 0x7, 0x078, 0x2,
		   40000, 0x6, 8000),
};

static unsigned int hi6421v530_regulator_ldo_get_mode(
					struct regulator_dev *rdev)
{
	struct hi6421v530_regulator_info *info;
	unsigned int reg_val;

	info = rdev_get_drvdata(rdev);
	regmap_read(rdev->regmap, rdev->desc->enable_reg, &reg_val);

	if (reg_val & (info->mode_mask))
		return REGULATOR_MODE_IDLE;

	return REGULATOR_MODE_NORMAL;
}

static int hi6421v530_regulator_ldo_set_mode(struct regulator_dev *rdev,
						unsigned int mode)
{
	struct hi6421v530_regulator_info *info;
	unsigned int new_mode;

	info = rdev_get_drvdata(rdev);
	switch (mode) {
	case REGULATOR_MODE_NORMAL:
		new_mode = 0;
		break;
	case REGULATOR_MODE_IDLE:
		new_mode = info->mode_mask;
		break;
	default:
		return -EINVAL;
	}

	regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
			   info->mode_mask, new_mode);

	return 0;
}


static const struct regulator_ops hi6421v530_ldo_ops = {
	.is_enabled = regulator_is_enabled_regmap,
	.enable = regulator_enable_regmap,
	.disable = regulator_disable_regmap,
	.list_voltage = regulator_list_voltage_table,
	.map_voltage = regulator_map_voltage_ascend,
	.get_voltage_sel = regulator_get_voltage_sel_regmap,
	.set_voltage_sel = regulator_set_voltage_sel_regmap,
	.get_mode = hi6421v530_regulator_ldo_get_mode,
	.set_mode = hi6421v530_regulator_ldo_set_mode,
};

static int hi6421v530_regulator_probe(struct platform_device *pdev)
{
	struct hi6421_pmic *pmic;
	struct regulator_dev *rdev;
	struct regulator_config config = { };
	unsigned int i;

	pmic = dev_get_drvdata(pdev->dev.parent);
	if (!pmic) {
		dev_err(&pdev->dev, "no pmic in the regulator parent node\n");
		return -ENODEV;
	}

	for (i = 0; i < ARRAY_SIZE(hi6421v530_regulator_info); i++) {
		config.dev = pdev->dev.parent;
		config.regmap = pmic->regmap;
		config.driver_data = &hi6421v530_regulator_info[i];

		rdev = devm_regulator_register(&pdev->dev,
				&hi6421v530_regulator_info[i].rdesc,
				&config);
		if (IS_ERR(rdev)) {
			dev_err(&pdev->dev, "failed to register regulator %s\n",
				hi6421v530_regulator_info[i].rdesc.name);
			return PTR_ERR(rdev);
		}
	}
	return 0;
}

static const struct platform_device_id hi6421v530_regulator_table[] = {
	{ .name = "hi6421v530-regulator" },
	{},
};
MODULE_DEVICE_TABLE(platform, hi6421v530_regulator_table);

static struct platform_driver hi6421v530_regulator_driver = {
	.id_table = hi6421v530_regulator_table,
	.driver = {
		.name	= "hi6421v530-regulator",
	},
	.probe	= hi6421v530_regulator_probe,
};
module_platform_driver(hi6421v530_regulator_driver);

MODULE_AUTHOR("Wang Xiaoyin <hw.wangxiaoyin@hisilicon.com>");
MODULE_DESCRIPTION("Hi6421v530 regulator driver");
MODULE_LICENSE("GPL v2");