// SPDX-License-Identifier: GPL-2.0
/*
 * BQ257XX Core Driver
 * Copyright (C) 2025 Chris Morgan <macromorgan@hotmail.com>
 */

#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/mfd/bq257xx.h>
#include <linux/mfd/core.h>
#include <linux/regmap.h>

static const struct regmap_range bq25703_readonly_reg_ranges[] = {
        regmap_reg_range(BQ25703_CHARGER_STATUS, BQ25703_MANUFACT_DEV_ID),
};

static const struct regmap_access_table bq25703_writeable_regs = {
        .no_ranges = bq25703_readonly_reg_ranges,
        .n_no_ranges = ARRAY_SIZE(bq25703_readonly_reg_ranges),
};

static const struct regmap_range bq25703_volatile_reg_ranges[] = {
        regmap_reg_range(BQ25703_CHARGE_OPTION_0, BQ25703_IIN_HOST),
        regmap_reg_range(BQ25703_CHARGER_STATUS, BQ25703_ADC_OPTION),
};

static const struct regmap_access_table bq25703_volatile_regs = {
        .yes_ranges = bq25703_volatile_reg_ranges,
        .n_yes_ranges = ARRAY_SIZE(bq25703_volatile_reg_ranges),
};

static const struct regmap_config bq25703_regmap_config = {
        .reg_bits = 8,
        .val_bits = 16,
        .max_register = BQ25703_ADC_OPTION,
        .cache_type = REGCACHE_MAPLE,
        .wr_table = &bq25703_writeable_regs,
        .volatile_table = &bq25703_volatile_regs,
        .val_format_endian = REGMAP_ENDIAN_LITTLE,
};

static const struct mfd_cell cells[] = {
        MFD_CELL_NAME("bq257xx-regulator"),
        MFD_CELL_NAME("bq257xx-charger"),
};

static int bq257xx_probe(struct i2c_client *client)
{
        struct bq257xx_device *ddata;
        int ret;

        ddata = devm_kzalloc(&client->dev, sizeof(*ddata), GFP_KERNEL);
        if (!ddata)
                return -ENOMEM;

        ddata->client = client;

        ddata->regmap = devm_regmap_init_i2c(client, &bq25703_regmap_config);
        if (IS_ERR(ddata->regmap)) {
                return dev_err_probe(&client->dev, PTR_ERR(ddata->regmap),
                                     "Failed to allocate register map\n");
        }

        i2c_set_clientdata(client, ddata);

        ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_AUTO,
                                   cells, ARRAY_SIZE(cells), NULL, 0, NULL);
        if (ret)
                return dev_err_probe(&client->dev, ret,
                                     "Failed to register child devices\n");

        return ret;
}

static const struct i2c_device_id bq257xx_i2c_ids[] = {
        { "bq25703a" },
        {}
};
MODULE_DEVICE_TABLE(i2c, bq257xx_i2c_ids);

static const struct of_device_id bq257xx_of_match[] = {
        { .compatible = "ti,bq25703a" },
        {}
};
MODULE_DEVICE_TABLE(of, bq257xx_of_match);

static struct i2c_driver bq257xx_driver = {
        .driver = {
                .name = "bq257xx",
                .of_match_table = bq257xx_of_match,
        },
        .probe = bq257xx_probe,
        .id_table = bq257xx_i2c_ids,
};
module_i2c_driver(bq257xx_driver);

MODULE_DESCRIPTION("bq257xx buck/boost/charger driver");
MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>");
MODULE_LICENSE("GPL");