root/drivers/regulator/max77826-regulator.c
// SPDX-License-Identifier: GPL-2.0-or-later
//
// max77826-regulator.c  - regulator driver for Maxim MAX77826
//
// Author: Iskren Chernev <iskren.chernev@gmail.com>

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
#include <linux/i2c.h>
#include <linux/regmap.h>

enum max77826_registers {
        MAX77826_REG_INT_SRC = 0x00,
        MAX77826_REG_SYS_INT,
        MAX77826_REG_INT1,
        MAX77826_REG_INT2,
        MAX77826_REG_BB_INT,
        MAX77826_REG_INT_SRC_M,
        MAX77826_REG_TOPSYS_INT_M,
        MAX77826_REG_INT1_M,
        MAX77826_REG_INT2_M,
        MAX77826_REG_BB_INT_M,
        MAX77826_REG_TOPSYS_STAT,
        MAX77826_REG_STAT1,
        MAX77826_REG_STAT2,
        MAX77826_REG_BB_STAT,
        /* 0x0E - 0x0F: Reserved */
        MAX77826_REG_LDO_OPMD1 = 0x10,
        MAX77826_REG_LDO_OPMD2,
        MAX77826_REG_LDO_OPMD3,
        MAX77826_REG_LDO_OPMD4,
        MAX77826_REG_B_BB_OPMD,
        /* 0x15 - 0x1F: Reserved */
        MAX77826_REG_LDO1_CFG = 0x20,
        MAX77826_REG_LDO2_CFG,
        MAX77826_REG_LDO3_CFG,
        MAX77826_REG_LDO4_CFG,
        MAX77826_REG_LDO5_CFG,
        MAX77826_REG_LDO6_CFG,
        MAX77826_REG_LDO7_CFG,
        MAX77826_REG_LDO8_CFG,
        MAX77826_REG_LDO9_CFG,
        MAX77826_REG_LDO10_CFG,
        MAX77826_REG_LDO11_CFG,
        MAX77826_REG_LDO12_CFG,
        MAX77826_REG_LDO13_CFG,
        MAX77826_REG_LDO14_CFG,
        MAX77826_REG_LDO15_CFG,
        /* 0x2F: Reserved */
        MAX77826_REG_BUCK_CFG = 0x30,
        MAX77826_REG_BUCK_VOUT,
        MAX77826_REG_BB_CFG,
        MAX77826_REG_BB_VOUT,
        /* 0x34 - 0x3F: Reserved */
        MAX77826_REG_BUCK_SS_FREQ = 0x40,
        MAX77826_REG_UVLO_FALL,
        /* 0x42 - 0xCE: Reserved */
        MAX77826_REG_DEVICE_ID = 0xCF,
};

enum max77826_regulators {
        MAX77826_LDO1 = 0,
        MAX77826_LDO2,
        MAX77826_LDO3,
        MAX77826_LDO4,
        MAX77826_LDO5,
        MAX77826_LDO6,
        MAX77826_LDO7,
        MAX77826_LDO8,
        MAX77826_LDO9,
        MAX77826_LDO10,
        MAX77826_LDO11,
        MAX77826_LDO12,
        MAX77826_LDO13,
        MAX77826_LDO14,
        MAX77826_LDO15,
        MAX77826_BUCK,
        MAX77826_BUCKBOOST,
        MAX77826_MAX_REGULATORS,
};

#define MAX77826_MASK_LDO               0x7f
#define MAX77826_MASK_BUCK              0xff
#define MAX77826_MASK_BUCKBOOST         0x7f
#define MAX77826_BUCK_RAMP_DELAY        12500

/* values in mV */
/* for LDO1-3 */
#define MAX77826_NMOS_LDO_VOLT_MIN      600000
#define MAX77826_NMOS_LDO_VOLT_MAX      2187500
#define MAX77826_NMOS_LDO_VOLT_STEP     12500

/* for LDO4-15 */
#define MAX77826_PMOS_LDO_VOLT_MIN      800000
#define MAX77826_PMOS_LDO_VOLT_MAX      3975000
#define MAX77826_PMOS_LDO_VOLT_STEP     25000

/* for BUCK */
#define MAX77826_BUCK_VOLT_MIN          500000
#define MAX77826_BUCK_VOLT_MAX          1800000
#define MAX77826_BUCK_VOLT_STEP         6250

/* for BUCKBOOST */
#define MAX77826_BUCKBOOST_VOLT_MIN     2600000
#define MAX77826_BUCKBOOST_VOLT_MAX     4187500
#define MAX77826_BUCKBOOST_VOLT_STEP    12500
#define MAX77826_VOLT_RANGE(_type)                                      \
        ((MAX77826_ ## _type ## _VOLT_MAX -                             \
          MAX77826_ ## _type ## _VOLT_MIN) /                            \
         MAX77826_ ## _type ## _VOLT_STEP + 1)

#define MAX77826_LDO(_id, _type)                                        \
        [MAX77826_LDO ## _id] = {                                       \
                .id = MAX77826_LDO ## _id,                              \
                .name = "LDO"#_id,                                      \
                .of_match = of_match_ptr("LDO"#_id),                    \
                .regulators_node = "regulators",                        \
                .ops = &max77826_most_ops,                              \
                .min_uV = MAX77826_ ## _type ## _LDO_VOLT_MIN,          \
                .uV_step = MAX77826_ ## _type ## _LDO_VOLT_STEP,        \
                .n_voltages = MAX77826_VOLT_RANGE(_type ## _LDO),       \
                .enable_reg = MAX77826_REG_LDO_OPMD1 + (_id - 1) / 4,   \
                .enable_mask = BIT(((_id - 1) % 4) * 2 + 1),            \
                .vsel_reg = MAX77826_REG_LDO1_CFG + (_id - 1),          \
                .vsel_mask = MAX77826_MASK_LDO,                         \
                .owner = THIS_MODULE,                                   \
        }

#define MAX77826_BUCK(_idx, _id, _ops)                                  \
        [MAX77826_ ## _id] = {                                          \
                .id = MAX77826_ ## _id,                                 \
                .name = #_id,                                           \
                .of_match = of_match_ptr(#_id),                         \
                .regulators_node = "regulators",                        \
                .ops = &_ops,                                           \
                .min_uV =  MAX77826_ ## _id ## _VOLT_MIN,               \
                .uV_step = MAX77826_ ## _id ## _VOLT_STEP,              \
                .n_voltages = MAX77826_VOLT_RANGE(_id),                 \
                .enable_reg = MAX77826_REG_B_BB_OPMD,                   \
                .enable_mask = BIT(_idx * 2 + 1),                       \
                .vsel_reg = MAX77826_REG_BUCK_VOUT + _idx * 2,          \
                .vsel_mask = MAX77826_MASK_ ## _id,                     \
                .owner = THIS_MODULE,                                   \
        }



struct max77826_regulator_info {
        struct regmap *regmap;
};

static const struct regmap_config max77826_regmap_config = {
        .reg_bits = 8,
        .val_bits = 8,
        .max_register = MAX77826_REG_DEVICE_ID,
};

static int max77826_set_voltage_time_sel(struct regulator_dev *,
                                unsigned int old_selector,
                                unsigned int new_selector);

static const struct regulator_ops max77826_most_ops = {
        .enable                 = regulator_enable_regmap,
        .disable                = regulator_disable_regmap,
        .is_enabled             = regulator_is_enabled_regmap,
        .list_voltage           = regulator_list_voltage_linear,
        .map_voltage            = regulator_map_voltage_linear,
        .get_voltage_sel        = regulator_get_voltage_sel_regmap,
        .set_voltage_sel        = regulator_set_voltage_sel_regmap,
};

static const struct regulator_ops max77826_buck_ops = {
        .enable                 = regulator_enable_regmap,
        .disable                = regulator_disable_regmap,
        .is_enabled             = regulator_is_enabled_regmap,
        .list_voltage           = regulator_list_voltage_linear,
        .map_voltage            = regulator_map_voltage_linear,
        .get_voltage_sel        = regulator_get_voltage_sel_regmap,
        .set_voltage_sel        = regulator_set_voltage_sel_regmap,
        .set_voltage_time_sel   = max77826_set_voltage_time_sel,
};

static const struct regulator_desc max77826_regulators_desc[] = {
        MAX77826_LDO(1, NMOS),
        MAX77826_LDO(2, NMOS),
        MAX77826_LDO(3, NMOS),
        MAX77826_LDO(4, PMOS),
        MAX77826_LDO(5, PMOS),
        MAX77826_LDO(6, PMOS),
        MAX77826_LDO(7, PMOS),
        MAX77826_LDO(8, PMOS),
        MAX77826_LDO(9, PMOS),
        MAX77826_LDO(10, PMOS),
        MAX77826_LDO(11, PMOS),
        MAX77826_LDO(12, PMOS),
        MAX77826_LDO(13, PMOS),
        MAX77826_LDO(14, PMOS),
        MAX77826_LDO(15, PMOS),
        MAX77826_BUCK(0, BUCK, max77826_buck_ops),
        MAX77826_BUCK(1, BUCKBOOST, max77826_most_ops),
};

static int max77826_set_voltage_time_sel(struct regulator_dev *rdev,
                                unsigned int old_selector,
                                unsigned int new_selector)
{
        if (new_selector > old_selector) {
                return DIV_ROUND_UP(MAX77826_BUCK_VOLT_STEP *
                                (new_selector - old_selector),
                                MAX77826_BUCK_RAMP_DELAY);
        }

        return 0;
}

static int max77826_read_device_id(struct regmap *regmap, struct device *dev)
{
        unsigned int device_id;
        int res;

        res = regmap_read(regmap, MAX77826_REG_DEVICE_ID, &device_id);
        if (!res)
                dev_dbg(dev, "DEVICE_ID: 0x%x\n", device_id);

        return res;
}

static int max77826_i2c_probe(struct i2c_client *client)
{
        struct device *dev = &client->dev;
        struct max77826_regulator_info *info;
        struct regulator_config config = {};
        struct regulator_dev *rdev;
        struct regmap *regmap;
        int i;

        info = devm_kzalloc(dev, sizeof(struct max77826_regulator_info),
                                GFP_KERNEL);
        if (!info)
                return -ENOMEM;

        regmap = devm_regmap_init_i2c(client, &max77826_regmap_config);
        if (IS_ERR(regmap)) {
                dev_err(dev, "Failed to allocate regmap!\n");
                return PTR_ERR(regmap);
        }

        info->regmap = regmap;
        i2c_set_clientdata(client, info);

        config.dev = dev;
        config.regmap = regmap;
        config.driver_data = info;

        for (i = 0; i < MAX77826_MAX_REGULATORS; i++) {
                rdev = devm_regulator_register(dev,
                                               &max77826_regulators_desc[i],
                                               &config);
                if (IS_ERR(rdev)) {
                        dev_err(dev, "Failed to register regulator!\n");
                        return PTR_ERR(rdev);
                }
        }

        return max77826_read_device_id(regmap, dev);
}

static const struct of_device_id __maybe_unused max77826_of_match[] = {
        { .compatible = "maxim,max77826" },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, max77826_of_match);

static const struct i2c_device_id max77826_id[] = {
        { "max77826-regulator" },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, max77826_id);

static struct i2c_driver max77826_regulator_driver = {
        .driver = {
                .name = "max77826",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
                .of_match_table = of_match_ptr(max77826_of_match),
        },
        .probe = max77826_i2c_probe,
        .id_table = max77826_id,
};
module_i2c_driver(max77826_regulator_driver);

MODULE_AUTHOR("Iskren Chernev <iskren.chernev@gmail.com>");
MODULE_DESCRIPTION("MAX77826 PMIC regulator driver");
MODULE_LICENSE("GPL");