// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/drivers/regulator/aat2870-regulator.c
 *
 * Copyright (c) 2011, NVIDIA Corporation.
 * Author: Jin Park <jinyoungp@nvidia.com>
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/mfd/aat2870.h>

struct aat2870_regulator {
        struct aat2870_data *aat2870;
        struct regulator_desc desc;

        u8 enable_addr;
        u8 enable_shift;
        u8 enable_mask;

        u8 voltage_addr;
        u8 voltage_shift;
        u8 voltage_mask;
};

static int aat2870_ldo_set_voltage_sel(struct regulator_dev *rdev,
                                       unsigned selector)
{
        struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
        struct aat2870_data *aat2870 = ri->aat2870;

        return aat2870->update(aat2870, ri->voltage_addr, ri->voltage_mask,
                               selector << ri->voltage_shift);
}

static int aat2870_ldo_get_voltage_sel(struct regulator_dev *rdev)
{
        struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
        struct aat2870_data *aat2870 = ri->aat2870;
        u8 val;
        int ret;

        ret = aat2870->read(aat2870, ri->voltage_addr, &val);
        if (ret)
                return ret;

        return (val & ri->voltage_mask) >> ri->voltage_shift;
}

static int aat2870_ldo_enable(struct regulator_dev *rdev)
{
        struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
        struct aat2870_data *aat2870 = ri->aat2870;

        return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask,
                               ri->enable_mask);
}

static int aat2870_ldo_disable(struct regulator_dev *rdev)
{
        struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
        struct aat2870_data *aat2870 = ri->aat2870;

        return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask, 0);
}

static int aat2870_ldo_is_enabled(struct regulator_dev *rdev)
{
        struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
        struct aat2870_data *aat2870 = ri->aat2870;
        u8 val;
        int ret;

        ret = aat2870->read(aat2870, ri->enable_addr, &val);
        if (ret)
                return ret;

        return val & ri->enable_mask ? 1 : 0;
}

static const struct regulator_ops aat2870_ldo_ops = {
        .list_voltage = regulator_list_voltage_table,
        .map_voltage = regulator_map_voltage_ascend,
        .set_voltage_sel = aat2870_ldo_set_voltage_sel,
        .get_voltage_sel = aat2870_ldo_get_voltage_sel,
        .enable = aat2870_ldo_enable,
        .disable = aat2870_ldo_disable,
        .is_enabled = aat2870_ldo_is_enabled,
};

static const unsigned int aat2870_ldo_voltages[] = {
        1200000, 1300000, 1500000, 1600000,
        1800000, 2000000, 2200000, 2500000,
        2600000, 2700000, 2800000, 2900000,
        3000000, 3100000, 3200000, 3300000,
};

#define AAT2870_LDO(ids)                                \
        {                                               \
                .desc = {                               \
                        .name = #ids,                   \
                        .id = AAT2870_ID_##ids,         \
                        .n_voltages = ARRAY_SIZE(aat2870_ldo_voltages), \
                        .volt_table = aat2870_ldo_voltages, \
                        .ops = &aat2870_ldo_ops,        \
                        .type = REGULATOR_VOLTAGE,      \
                        .owner = THIS_MODULE,           \
                },                                      \
        }

static struct aat2870_regulator aat2870_regulators[] = {
        AAT2870_LDO(LDOA),
        AAT2870_LDO(LDOB),
        AAT2870_LDO(LDOC),
        AAT2870_LDO(LDOD),
};

static struct aat2870_regulator *aat2870_get_regulator(int id)
{
        struct aat2870_regulator *ri = NULL;
        int i;

        for (i = 0; i < ARRAY_SIZE(aat2870_regulators); i++) {
                ri = &aat2870_regulators[i];
                if (ri->desc.id == id)
                        break;
        }

        if (i == ARRAY_SIZE(aat2870_regulators))
                return NULL;

        ri->enable_addr = AAT2870_LDO_EN;
        ri->enable_shift = id - AAT2870_ID_LDOA;
        ri->enable_mask = 0x1 << ri->enable_shift;

        ri->voltage_addr = (id - AAT2870_ID_LDOA) / 2 ?
                           AAT2870_LDO_CD : AAT2870_LDO_AB;
        ri->voltage_shift = (id - AAT2870_ID_LDOA) % 2 ? 0 : 4;
        ri->voltage_mask = 0xF << ri->voltage_shift;

        return ri;
}

static int aat2870_regulator_probe(struct platform_device *pdev)
{
        struct aat2870_regulator *ri;
        struct regulator_config config = { };
        struct regulator_dev *rdev;

        ri = aat2870_get_regulator(pdev->id);
        if (!ri) {
                dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id);
                return -EINVAL;
        }
        ri->aat2870 = dev_get_drvdata(pdev->dev.parent);

        config.dev = &pdev->dev;
        config.driver_data = ri;
        config.init_data = dev_get_platdata(&pdev->dev);

        rdev = devm_regulator_register(&pdev->dev, &ri->desc, &config);
        if (IS_ERR(rdev)) {
                dev_err(&pdev->dev, "Failed to register regulator %s\n",
                        ri->desc.name);
                return PTR_ERR(rdev);
        }
        platform_set_drvdata(pdev, rdev);

        return 0;
}

static struct platform_driver aat2870_regulator_driver = {
        .driver = {
                .name   = "aat2870-regulator",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
        .probe  = aat2870_regulator_probe,
};

static int __init aat2870_regulator_init(void)
{
        return platform_driver_register(&aat2870_regulator_driver);
}
subsys_initcall(aat2870_regulator_init);

static void __exit aat2870_regulator_exit(void)
{
        platform_driver_unregister(&aat2870_regulator_driver);
}
module_exit(aat2870_regulator_exit);

MODULE_DESCRIPTION("AnalogicTech AAT2870 Regulator");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");
MODULE_ALIAS("platform:aat2870-regulator");