root/drivers/regulator/slg51000-regulator.c
// SPDX-License-Identifier: GPL-2.0+
//
// SLG51000 High PSRR, Multi-Output Regulators
// Copyright (C) 2019  Dialog Semiconductor
//
// Author: Eric Jeong <eric.jeong.opensource@diasemi.com>

#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include "slg51000-regulator.h"

#define SLG51000_SCTL_EVT               7
#define SLG51000_MAX_EVT_REGISTER       8
#define SLG51000_LDOHP_LV_MIN           1200000
#define SLG51000_LDOHP_HV_MIN           2400000

enum slg51000_regulators {
        SLG51000_REGULATOR_LDO1 = 0,
        SLG51000_REGULATOR_LDO2,
        SLG51000_REGULATOR_LDO3,
        SLG51000_REGULATOR_LDO4,
        SLG51000_REGULATOR_LDO5,
        SLG51000_REGULATOR_LDO6,
        SLG51000_REGULATOR_LDO7,
        SLG51000_MAX_REGULATORS,
};

struct slg51000 {
        struct device *dev;
        struct regmap *regmap;
        struct regulator_desc *rdesc[SLG51000_MAX_REGULATORS];
        struct regulator_dev *rdev[SLG51000_MAX_REGULATORS];
        struct gpio_desc *cs_gpiod;
        int chip_irq;
};

struct slg51000_evt_sta {
        unsigned int ereg;
        unsigned int sreg;
};

static const struct slg51000_evt_sta es_reg[SLG51000_MAX_EVT_REGISTER] = {
        {SLG51000_LDO1_EVENT, SLG51000_LDO1_STATUS},
        {SLG51000_LDO2_EVENT, SLG51000_LDO2_STATUS},
        {SLG51000_LDO3_EVENT, SLG51000_LDO3_STATUS},
        {SLG51000_LDO4_EVENT, SLG51000_LDO4_STATUS},
        {SLG51000_LDO5_EVENT, SLG51000_LDO5_STATUS},
        {SLG51000_LDO6_EVENT, SLG51000_LDO6_STATUS},
        {SLG51000_LDO7_EVENT, SLG51000_LDO7_STATUS},
        {SLG51000_SYSCTL_EVENT, SLG51000_SYSCTL_STATUS},
};

static const struct regmap_range slg51000_writeable_ranges[] = {
        regmap_reg_range(SLG51000_SYSCTL_MATRIX_CONF_A,
                         SLG51000_SYSCTL_MATRIX_CONF_A),
        regmap_reg_range(SLG51000_LDO1_VSEL, SLG51000_LDO1_VSEL),
        regmap_reg_range(SLG51000_LDO1_MINV, SLG51000_LDO1_MAXV),
        regmap_reg_range(SLG51000_LDO1_IRQ_MASK, SLG51000_LDO1_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO2_VSEL, SLG51000_LDO2_VSEL),
        regmap_reg_range(SLG51000_LDO2_MINV, SLG51000_LDO2_MAXV),
        regmap_reg_range(SLG51000_LDO2_IRQ_MASK, SLG51000_LDO2_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO3_VSEL, SLG51000_LDO3_VSEL),
        regmap_reg_range(SLG51000_LDO3_MINV, SLG51000_LDO3_MAXV),
        regmap_reg_range(SLG51000_LDO3_IRQ_MASK, SLG51000_LDO3_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO4_VSEL, SLG51000_LDO4_VSEL),
        regmap_reg_range(SLG51000_LDO4_MINV, SLG51000_LDO4_MAXV),
        regmap_reg_range(SLG51000_LDO4_IRQ_MASK, SLG51000_LDO4_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO5_VSEL, SLG51000_LDO5_VSEL),
        regmap_reg_range(SLG51000_LDO5_MINV, SLG51000_LDO5_MAXV),
        regmap_reg_range(SLG51000_LDO5_IRQ_MASK, SLG51000_LDO5_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO6_VSEL, SLG51000_LDO6_VSEL),
        regmap_reg_range(SLG51000_LDO6_MINV, SLG51000_LDO6_MAXV),
        regmap_reg_range(SLG51000_LDO6_IRQ_MASK, SLG51000_LDO6_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO7_VSEL, SLG51000_LDO7_VSEL),
        regmap_reg_range(SLG51000_LDO7_MINV, SLG51000_LDO7_MAXV),
        regmap_reg_range(SLG51000_LDO7_IRQ_MASK, SLG51000_LDO7_IRQ_MASK),
        regmap_reg_range(SLG51000_OTP_IRQ_MASK, SLG51000_OTP_IRQ_MASK),
};

static const struct regmap_range slg51000_readable_ranges[] = {
        regmap_reg_range(SLG51000_SYSCTL_PATN_ID_B0,
                         SLG51000_SYSCTL_PATN_ID_B2),
        regmap_reg_range(SLG51000_SYSCTL_SYS_CONF_A,
                         SLG51000_SYSCTL_SYS_CONF_A),
        regmap_reg_range(SLG51000_SYSCTL_SYS_CONF_D,
                         SLG51000_SYSCTL_MATRIX_CONF_B),
        regmap_reg_range(SLG51000_SYSCTL_REFGEN_CONF_C,
                         SLG51000_SYSCTL_UVLO_CONF_A),
        regmap_reg_range(SLG51000_SYSCTL_FAULT_LOG1, SLG51000_SYSCTL_IRQ_MASK),
        regmap_reg_range(SLG51000_IO_GPIO1_CONF, SLG51000_IO_GPIO_STATUS),
        regmap_reg_range(SLG51000_LUTARRAY_LUT_VAL_0,
                         SLG51000_LUTARRAY_LUT_VAL_11),
        regmap_reg_range(SLG51000_MUXARRAY_INPUT_SEL_0,
                         SLG51000_MUXARRAY_INPUT_SEL_63),
        regmap_reg_range(SLG51000_PWRSEQ_RESOURCE_EN_0,
                         SLG51000_PWRSEQ_INPUT_SENSE_CONF_B),
        regmap_reg_range(SLG51000_LDO1_VSEL, SLG51000_LDO1_VSEL),
        regmap_reg_range(SLG51000_LDO1_MINV, SLG51000_LDO1_MAXV),
        regmap_reg_range(SLG51000_LDO1_MISC1, SLG51000_LDO1_VSEL_ACTUAL),
        regmap_reg_range(SLG51000_LDO1_EVENT, SLG51000_LDO1_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO2_VSEL, SLG51000_LDO2_VSEL),
        regmap_reg_range(SLG51000_LDO2_MINV, SLG51000_LDO2_MAXV),
        regmap_reg_range(SLG51000_LDO2_MISC1, SLG51000_LDO2_VSEL_ACTUAL),
        regmap_reg_range(SLG51000_LDO2_EVENT, SLG51000_LDO2_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO3_VSEL, SLG51000_LDO3_VSEL),
        regmap_reg_range(SLG51000_LDO3_MINV, SLG51000_LDO3_MAXV),
        regmap_reg_range(SLG51000_LDO3_CONF1, SLG51000_LDO3_VSEL_ACTUAL),
        regmap_reg_range(SLG51000_LDO3_EVENT, SLG51000_LDO3_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO4_VSEL, SLG51000_LDO4_VSEL),
        regmap_reg_range(SLG51000_LDO4_MINV, SLG51000_LDO4_MAXV),
        regmap_reg_range(SLG51000_LDO4_CONF1, SLG51000_LDO4_VSEL_ACTUAL),
        regmap_reg_range(SLG51000_LDO4_EVENT, SLG51000_LDO4_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO5_VSEL, SLG51000_LDO5_VSEL),
        regmap_reg_range(SLG51000_LDO5_MINV, SLG51000_LDO5_MAXV),
        regmap_reg_range(SLG51000_LDO5_TRIM2, SLG51000_LDO5_TRIM2),
        regmap_reg_range(SLG51000_LDO5_CONF1, SLG51000_LDO5_VSEL_ACTUAL),
        regmap_reg_range(SLG51000_LDO5_EVENT, SLG51000_LDO5_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO6_VSEL, SLG51000_LDO6_VSEL),
        regmap_reg_range(SLG51000_LDO6_MINV, SLG51000_LDO6_MAXV),
        regmap_reg_range(SLG51000_LDO6_TRIM2, SLG51000_LDO6_TRIM2),
        regmap_reg_range(SLG51000_LDO6_CONF1, SLG51000_LDO6_VSEL_ACTUAL),
        regmap_reg_range(SLG51000_LDO6_EVENT, SLG51000_LDO6_IRQ_MASK),
        regmap_reg_range(SLG51000_LDO7_VSEL, SLG51000_LDO7_VSEL),
        regmap_reg_range(SLG51000_LDO7_MINV, SLG51000_LDO7_MAXV),
        regmap_reg_range(SLG51000_LDO7_CONF1, SLG51000_LDO7_VSEL_ACTUAL),
        regmap_reg_range(SLG51000_LDO7_EVENT, SLG51000_LDO7_IRQ_MASK),
        regmap_reg_range(SLG51000_OTP_EVENT, SLG51000_OTP_EVENT),
        regmap_reg_range(SLG51000_OTP_IRQ_MASK, SLG51000_OTP_IRQ_MASK),
        regmap_reg_range(SLG51000_OTP_LOCK_OTP_PROG, SLG51000_OTP_LOCK_CTRL),
        regmap_reg_range(SLG51000_LOCK_GLOBAL_LOCK_CTRL1,
                         SLG51000_LOCK_GLOBAL_LOCK_CTRL1),
};

static const struct regmap_range slg51000_volatile_ranges[] = {
        regmap_reg_range(SLG51000_SYSCTL_FAULT_LOG1, SLG51000_SYSCTL_STATUS),
        regmap_reg_range(SLG51000_IO_GPIO_STATUS, SLG51000_IO_GPIO_STATUS),
        regmap_reg_range(SLG51000_LDO1_EVENT, SLG51000_LDO1_STATUS),
        regmap_reg_range(SLG51000_LDO2_EVENT, SLG51000_LDO2_STATUS),
        regmap_reg_range(SLG51000_LDO3_EVENT, SLG51000_LDO3_STATUS),
        regmap_reg_range(SLG51000_LDO4_EVENT, SLG51000_LDO4_STATUS),
        regmap_reg_range(SLG51000_LDO5_EVENT, SLG51000_LDO5_STATUS),
        regmap_reg_range(SLG51000_LDO6_EVENT, SLG51000_LDO6_STATUS),
        regmap_reg_range(SLG51000_LDO7_EVENT, SLG51000_LDO7_STATUS),
        regmap_reg_range(SLG51000_OTP_EVENT, SLG51000_OTP_EVENT),
};

static const struct regmap_access_table slg51000_writeable_table = {
        .yes_ranges     = slg51000_writeable_ranges,
        .n_yes_ranges   = ARRAY_SIZE(slg51000_writeable_ranges),
};

static const struct regmap_access_table slg51000_readable_table = {
        .yes_ranges     = slg51000_readable_ranges,
        .n_yes_ranges   = ARRAY_SIZE(slg51000_readable_ranges),
};

static const struct regmap_access_table slg51000_volatile_table = {
        .yes_ranges     = slg51000_volatile_ranges,
        .n_yes_ranges   = ARRAY_SIZE(slg51000_volatile_ranges),
};

static const struct regmap_config slg51000_regmap_config = {
        .reg_bits = 16,
        .val_bits = 8,
        .max_register = 0x8000,
        .wr_table = &slg51000_writeable_table,
        .rd_table = &slg51000_readable_table,
        .volatile_table = &slg51000_volatile_table,
};

static const struct regulator_ops slg51000_regl_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 slg51000_switch_ops = {
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .is_enabled = regulator_is_enabled_regmap,
};

static int slg51000_of_parse_cb(struct device_node *np,
                                const struct regulator_desc *desc,
                                struct regulator_config *config)
{
        struct gpio_desc *ena_gpiod;

        ena_gpiod = fwnode_gpiod_get_index(of_fwnode_handle(np), "enable", 0,
                                           GPIOD_OUT_LOW |
                                                GPIOD_FLAGS_BIT_NONEXCLUSIVE,
                                           "gpio-en-ldo");
        if (!IS_ERR(ena_gpiod))
                config->ena_gpiod = ena_gpiod;

        return 0;
}

#define SLG51000_REGL_DESC(_id, _name, _s_name, _min, _step) \
        [SLG51000_REGULATOR_##_id] = {                             \
                .name = #_name,                                    \
                .supply_name = _s_name,                            \
                .id = SLG51000_REGULATOR_##_id,                    \
                .of_match = of_match_ptr(#_name),                  \
                .of_parse_cb = slg51000_of_parse_cb,               \
                .ops = &slg51000_regl_ops,                         \
                .regulators_node = of_match_ptr("regulators"),     \
                .n_voltages = 256,                                 \
                .min_uV = _min,                                    \
                .uV_step = _step,                                  \
                .linear_min_sel = 0,                               \
                .vsel_mask = SLG51000_VSEL_MASK,                   \
                .vsel_reg = SLG51000_##_id##_VSEL,                 \
                .enable_reg = SLG51000_SYSCTL_MATRIX_CONF_A,       \
                .enable_mask = BIT(SLG51000_REGULATOR_##_id),      \
                .type = REGULATOR_VOLTAGE,                         \
                .owner = THIS_MODULE,                              \
        }

static struct regulator_desc regls_desc[SLG51000_MAX_REGULATORS] = {
        SLG51000_REGL_DESC(LDO1, ldo1, NULL,   2400000,  5000),
        SLG51000_REGL_DESC(LDO2, ldo2, NULL,   2400000,  5000),
        SLG51000_REGL_DESC(LDO3, ldo3, "vin3", 1200000, 10000),
        SLG51000_REGL_DESC(LDO4, ldo4, "vin4", 1200000, 10000),
        SLG51000_REGL_DESC(LDO5, ldo5, "vin5",  400000,  5000),
        SLG51000_REGL_DESC(LDO6, ldo6, "vin6",  400000,  5000),
        SLG51000_REGL_DESC(LDO7, ldo7, "vin7", 1200000, 10000),
};

static int slg51000_regulator_init(struct slg51000 *chip)
{
        struct regulator_config config = { };
        struct regulator_desc *rdesc;
        unsigned int reg, val;
        u8 vsel_range[2];
        int id, ret = 0;
        const unsigned int min_regs[SLG51000_MAX_REGULATORS] = {
                SLG51000_LDO1_MINV, SLG51000_LDO2_MINV, SLG51000_LDO3_MINV,
                SLG51000_LDO4_MINV, SLG51000_LDO5_MINV, SLG51000_LDO6_MINV,
                SLG51000_LDO7_MINV,
        };

        for (id = 0; id < SLG51000_MAX_REGULATORS; id++) {
                chip->rdesc[id] = &regls_desc[id];
                rdesc = chip->rdesc[id];
                config.regmap = chip->regmap;
                config.dev = chip->dev;
                config.driver_data = chip;

                ret = regmap_bulk_read(chip->regmap, min_regs[id],
                                       vsel_range, 2);
                if (ret < 0) {
                        dev_err(chip->dev,
                                "Failed to read the MIN register\n");
                        return ret;
                }

                switch (id) {
                case SLG51000_REGULATOR_LDO1:
                case SLG51000_REGULATOR_LDO2:
                        if (id == SLG51000_REGULATOR_LDO1)
                                reg = SLG51000_LDO1_MISC1;
                        else
                                reg = SLG51000_LDO2_MISC1;

                        ret = regmap_read(chip->regmap, reg, &val);
                        if (ret < 0) {
                                dev_err(chip->dev,
                                        "Failed to read voltage range of ldo%d\n",
                                        id + 1);
                                return ret;
                        }

                        rdesc->linear_min_sel = vsel_range[0];
                        rdesc->n_voltages = vsel_range[1] + 1;
                        if (val & SLG51000_SEL_VRANGE_MASK)
                                rdesc->min_uV = SLG51000_LDOHP_HV_MIN
                                                + (vsel_range[0]
                                                   * rdesc->uV_step);
                        else
                                rdesc->min_uV = SLG51000_LDOHP_LV_MIN
                                                + (vsel_range[0]
                                                   * rdesc->uV_step);
                        break;

                case SLG51000_REGULATOR_LDO5:
                case SLG51000_REGULATOR_LDO6:
                        if (id == SLG51000_REGULATOR_LDO5)
                                reg = SLG51000_LDO5_TRIM2;
                        else
                                reg = SLG51000_LDO6_TRIM2;

                        ret = regmap_read(chip->regmap, reg, &val);
                        if (ret < 0) {
                                dev_err(chip->dev,
                                        "Failed to read LDO mode register\n");
                                return ret;
                        }

                        if (val & SLG51000_SEL_BYP_MODE_MASK) {
                                rdesc->ops = &slg51000_switch_ops;
                                rdesc->n_voltages = 0;
                                rdesc->min_uV = 0;
                                rdesc->uV_step = 0;
                                rdesc->linear_min_sel = 0;
                                break;
                        }
                        fallthrough;    /* to the check below */

                default:
                        rdesc->linear_min_sel = vsel_range[0];
                        rdesc->n_voltages = vsel_range[1] + 1;
                        rdesc->min_uV = rdesc->min_uV
                                        + (vsel_range[0] * rdesc->uV_step);
                        break;
                }

                chip->rdev[id] = devm_regulator_register(chip->dev, rdesc,
                                                         &config);
                if (IS_ERR(chip->rdev[id])) {
                        ret = PTR_ERR(chip->rdev[id]);
                        dev_err(chip->dev,
                                "Failed to register regulator(%s):%d\n",
                                chip->rdesc[id]->name, ret);
                        return ret;
                }
        }

        return 0;
}

static irqreturn_t slg51000_irq_handler(int irq, void *data)
{
        struct slg51000 *chip = data;
        struct regmap *regmap = chip->regmap;
        enum { R0 = 0, R1, R2, REG_MAX };
        u8 evt[SLG51000_MAX_EVT_REGISTER][REG_MAX];
        int ret, i, handled = IRQ_NONE;
        unsigned int evt_otp, mask_otp;

        /* Read event[R0], status[R1] and mask[R2] register */
        for (i = 0; i < SLG51000_MAX_EVT_REGISTER; i++) {
                ret = regmap_bulk_read(regmap, es_reg[i].ereg, evt[i], REG_MAX);
                if (ret < 0) {
                        dev_err(chip->dev,
                                "Failed to read event registers(%d)\n", ret);
                        return IRQ_NONE;
                }
        }

        ret = regmap_read(regmap, SLG51000_OTP_EVENT, &evt_otp);
        if (ret < 0) {
                dev_err(chip->dev,
                        "Failed to read otp event registers(%d)\n", ret);
                return IRQ_NONE;
        }

        ret = regmap_read(regmap, SLG51000_OTP_IRQ_MASK, &mask_otp);
        if (ret < 0) {
                dev_err(chip->dev,
                        "Failed to read otp mask register(%d)\n", ret);
                return IRQ_NONE;
        }

        if ((evt_otp & SLG51000_EVT_CRC_MASK) &&
            !(mask_otp & SLG51000_IRQ_CRC_MASK)) {
                dev_info(chip->dev,
                         "OTP has been read or OTP crc is not zero\n");
                handled = IRQ_HANDLED;
        }

        for (i = 0; i < SLG51000_MAX_REGULATORS; i++) {
                if (!(evt[i][R2] & SLG51000_IRQ_ILIM_FLAG_MASK) &&
                    (evt[i][R0] & SLG51000_EVT_ILIM_FLAG_MASK)) {
                        regulator_notifier_call_chain(chip->rdev[i],
                                            REGULATOR_EVENT_OVER_CURRENT, NULL);

                        if (evt[i][R1] & SLG51000_STA_ILIM_FLAG_MASK)
                                dev_warn(chip->dev,
                                         "Over-current limit(ldo%d)\n", i + 1);
                        handled = IRQ_HANDLED;
                }
        }

        if (!(evt[SLG51000_SCTL_EVT][R2] & SLG51000_IRQ_HIGH_TEMP_WARN_MASK) &&
            (evt[SLG51000_SCTL_EVT][R0] & SLG51000_EVT_HIGH_TEMP_WARN_MASK)) {
                for (i = 0; i < SLG51000_MAX_REGULATORS; i++) {
                        if (!(evt[i][R1] & SLG51000_STA_ILIM_FLAG_MASK) &&
                            (evt[i][R1] & SLG51000_STA_VOUT_OK_FLAG_MASK)) {
                                regulator_notifier_call_chain(chip->rdev[i],
                                               REGULATOR_EVENT_OVER_TEMP, NULL);
                        }
                }
                handled = IRQ_HANDLED;
                if (evt[SLG51000_SCTL_EVT][R1] &
                    SLG51000_STA_HIGH_TEMP_WARN_MASK)
                        dev_warn(chip->dev, "High temperature warning!\n");
        }

        return handled;
}

static void slg51000_clear_fault_log(struct slg51000 *chip)
{
        unsigned int val = 0;
        int ret = 0;

        ret = regmap_read(chip->regmap, SLG51000_SYSCTL_FAULT_LOG1, &val);
        if (ret < 0) {
                dev_err(chip->dev, "Failed to read Fault log register\n");
                return;
        }

        if (val & SLG51000_FLT_OVER_TEMP_MASK)
                dev_dbg(chip->dev, "Fault log: FLT_OVER_TEMP\n");
        if (val & SLG51000_FLT_POWER_SEQ_CRASH_REQ_MASK)
                dev_dbg(chip->dev, "Fault log: FLT_POWER_SEQ_CRASH_REQ\n");
        if (val & SLG51000_FLT_RST_MASK)
                dev_dbg(chip->dev, "Fault log: FLT_RST\n");
        if (val & SLG51000_FLT_POR_MASK)
                dev_dbg(chip->dev, "Fault log: FLT_POR\n");
}

static int slg51000_i2c_probe(struct i2c_client *client)
{
        struct device *dev = &client->dev;
        struct slg51000 *chip;
        struct gpio_desc *cs_gpiod;
        int error, ret;

        chip = devm_kzalloc(dev, sizeof(struct slg51000), GFP_KERNEL);
        if (!chip)
                return -ENOMEM;

        cs_gpiod = devm_gpiod_get_optional(dev, "dlg,cs",
                                           GPIOD_OUT_HIGH |
                                                GPIOD_FLAGS_BIT_NONEXCLUSIVE);
        if (IS_ERR(cs_gpiod))
                return PTR_ERR(cs_gpiod);

        if (cs_gpiod) {
                dev_info(dev, "Found chip selector property\n");
                chip->cs_gpiod = cs_gpiod;
        }

        usleep_range(10000, 11000);

        i2c_set_clientdata(client, chip);
        chip->chip_irq = client->irq;
        chip->dev = dev;
        chip->regmap = devm_regmap_init_i2c(client, &slg51000_regmap_config);
        if (IS_ERR(chip->regmap)) {
                error = PTR_ERR(chip->regmap);
                dev_err(dev, "Failed to allocate register map: %d\n",
                        error);
                return error;
        }

        ret = slg51000_regulator_init(chip);
        if (ret < 0) {
                dev_err(chip->dev, "Failed to init regulator(%d)\n", ret);
                return ret;
        }

        slg51000_clear_fault_log(chip);

        if (chip->chip_irq) {
                ret = devm_request_threaded_irq(dev, chip->chip_irq, NULL,
                                                slg51000_irq_handler,
                                                (IRQF_TRIGGER_HIGH |
                                                IRQF_ONESHOT),
                                                "slg51000-irq", chip);
                if (ret != 0) {
                        dev_err(dev, "Failed to request IRQ: %d\n",
                                chip->chip_irq);
                        return ret;
                }
        } else {
                dev_info(dev, "No IRQ configured\n");
        }

        return ret;
}

static const struct i2c_device_id slg51000_i2c_id[] = {
        { "slg51000" },
        {}
};
MODULE_DEVICE_TABLE(i2c, slg51000_i2c_id);

static struct i2c_driver slg51000_regulator_driver = {
        .driver = {
                .name = "slg51000-regulator",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
        .probe = slg51000_i2c_probe,
        .id_table = slg51000_i2c_id,
};

module_i2c_driver(slg51000_regulator_driver);

MODULE_AUTHOR("Eric Jeong <eric.jeong.opensource@diasemi.com>");
MODULE_DESCRIPTION("SLG51000 regulator driver");
MODULE_LICENSE("GPL");