// SPDX-License-Identifier: GPL-2.0
//
// Copyright (c) 2015 MediaTek Inc.
// Author: Henry Chen <henryc.chen@mediatek.com>

#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/mt6311.h>
#include <linux/slab.h>
#include "mt6311-regulator.h"

static const struct regmap_config mt6311_regmap_config = {
        .reg_bits = 8,
        .val_bits = 8,
        .max_register = MT6311_FQMTR_CON4,
        .cache_type = REGCACHE_MAPLE,
};

/* Default limits measured in millivolts and milliamps */
#define MT6311_MIN_UV           600000
#define MT6311_MAX_UV           1393750
#define MT6311_STEP_UV          6250

static const struct regulator_ops mt6311_buck_ops = {
        .list_voltage = regulator_list_voltage_linear,
        .map_voltage = regulator_map_voltage_linear,
        .set_voltage_sel = regulator_set_voltage_sel_regmap,
        .get_voltage_sel = regulator_get_voltage_sel_regmap,
        .set_voltage_time_sel = regulator_set_voltage_time_sel,
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .is_enabled = regulator_is_enabled_regmap,
};

static const struct regulator_ops mt6311_ldo_ops = {
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .is_enabled = regulator_is_enabled_regmap,
};

#define MT6311_BUCK(_id) \
{\
        .name = #_id,\
        .ops = &mt6311_buck_ops,\
        .of_match = of_match_ptr(#_id),\
        .regulators_node = of_match_ptr("regulators"),\
        .type = REGULATOR_VOLTAGE,\
        .id = MT6311_ID_##_id,\
        .n_voltages = (MT6311_MAX_UV - MT6311_MIN_UV) / MT6311_STEP_UV + 1,\
        .min_uV = MT6311_MIN_UV,\
        .uV_step = MT6311_STEP_UV,\
        .owner = THIS_MODULE,\
        .enable_reg = MT6311_VDVFS11_CON9,\
        .enable_mask = MT6311_PMIC_VDVFS11_EN_MASK,\
        .vsel_reg = MT6311_VDVFS11_CON12,\
        .vsel_mask = MT6311_PMIC_VDVFS11_VOSEL_MASK,\
}

#define MT6311_LDO(_id) \
{\
        .name = #_id,\
        .ops = &mt6311_ldo_ops,\
        .of_match = of_match_ptr(#_id),\
        .regulators_node = of_match_ptr("regulators"),\
        .type = REGULATOR_VOLTAGE,\
        .id = MT6311_ID_##_id,\
        .owner = THIS_MODULE,\
        .enable_reg = MT6311_LDO_CON3,\
        .enable_mask = MT6311_PMIC_RG_VBIASN_EN_MASK,\
}

static const struct regulator_desc mt6311_regulators[] = {
        MT6311_BUCK(VDVFS),
        MT6311_LDO(VBIASN),
};

/*
 * I2C driver interface functions
 */
static int mt6311_i2c_probe(struct i2c_client *i2c)
{
        struct regulator_config config = { };
        struct regulator_dev *rdev;
        struct regmap *regmap;
        int i, ret;
        unsigned int data;

        regmap = devm_regmap_init_i2c(i2c, &mt6311_regmap_config);
        if (IS_ERR(regmap)) {
                ret = PTR_ERR(regmap);
                dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
                        ret);
                return ret;
        }

        ret = regmap_read(regmap, MT6311_SWCID, &data);
        if (ret < 0) {
                dev_err(&i2c->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
                return ret;
        }

        switch (data) {
        case MT6311_E1_CID_CODE:
        case MT6311_E2_CID_CODE:
        case MT6311_E3_CID_CODE:
                break;
        default:
                dev_err(&i2c->dev, "Unsupported device id = 0x%x.\n", data);
                return -ENODEV;
        }

        for (i = 0; i < MT6311_MAX_REGULATORS; i++) {
                config.dev = &i2c->dev;
                config.regmap = regmap;

                rdev = devm_regulator_register(&i2c->dev,
                        &mt6311_regulators[i], &config);
                if (IS_ERR(rdev)) {
                        dev_err(&i2c->dev,
                                "Failed to register MT6311 regulator\n");
                        return PTR_ERR(rdev);
                }
        }

        return 0;
}

static const struct i2c_device_id mt6311_i2c_id[] = {
        { "mt6311" },
        {}
};
MODULE_DEVICE_TABLE(i2c, mt6311_i2c_id);

#ifdef CONFIG_OF
static const struct of_device_id mt6311_dt_ids[] = {
        { .compatible = "mediatek,mt6311-regulator",
          .data = &mt6311_i2c_id[0] },
        {},
};
MODULE_DEVICE_TABLE(of, mt6311_dt_ids);
#endif

static struct i2c_driver mt6311_regulator_driver = {
        .driver = {
                .name = "mt6311",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
                .of_match_table = of_match_ptr(mt6311_dt_ids),
        },
        .probe = mt6311_i2c_probe,
        .id_table = mt6311_i2c_id,
};

module_i2c_driver(mt6311_regulator_driver);

MODULE_AUTHOR("Henry Chen <henryc.chen@mediatek.com>");
MODULE_DESCRIPTION("Regulator device driver for Mediatek MT6311");
MODULE_LICENSE("GPL v2");