root/drivers/regulator/rt5120-regulator.c
// SPDX-License-Identifier: GPL-2.0+

#include <linux/bits.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>

#define RT5120_REG_PGSTAT       0x03
#define RT5120_REG_CH1VID       0x06
#define RT5120_REG_CH1SLPVID    0x07
#define RT5120_REG_ENABLE       0x08
#define RT5120_REG_MODECTL      0x09
#define RT5120_REG_UVOVPROT     0x0A
#define RT5120_REG_SLPCTL       0x0C
#define RT5120_REG_INTSTAT      0x1E
#define RT5120_REG_DISCHG       0x1F

#define RT5120_OUTPG_MASK(rid)  BIT(rid + 1)
#define RT5120_OUTUV_MASK(rid)  BIT(rid + 9)
#define RT5120_OUTOV_MASK(rid)  BIT(rid + 16)
#define RT5120_CH1VID_MASK      GENMASK(6, 0)
#define RT5120_RIDEN_MASK(rid)  BIT(rid + 1)
#define RT5120_RADEN_MASK(rid)  BIT(rid)
#define RT5120_FPWM_MASK(rid)   BIT(rid + 1)
#define RT5120_UVHICCUP_MASK    BIT(1)
#define RT5120_OVHICCUP_MASK    BIT(0)
#define RT5120_HOTDIE_MASK      BIT(1)

#define RT5120_BUCK1_MINUV      600000
#define RT5120_BUCK1_MAXUV      1393750
#define RT5120_BUCK1_STEPUV     6250
#define RT5120_BUCK1_NUM_VOLT   0x80

#define RT5120_AUTO_MODE        0
#define RT5120_FPWM_MODE        1

enum {
        RT5120_REGULATOR_BUCK1 = 0,
        RT5120_REGULATOR_BUCK2,
        RT5120_REGULATOR_BUCK3,
        RT5120_REGULATOR_BUCK4,
        RT5120_REGULATOR_LDO,
        RT5120_REGULATOR_EXTEN,
        RT5120_MAX_REGULATOR
};

struct rt5120_priv {
        struct device *dev;
        struct regmap *regmap;
        struct regulator_desc rdesc[RT5120_MAX_REGULATOR];
};

static int rt5120_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
{
        struct regmap *regmap = rdev_get_regmap(rdev);
        int rid = rdev_get_id(rdev);
        unsigned int mask = RT5120_FPWM_MASK(rid), val;

        switch (mode) {
        case REGULATOR_MODE_NORMAL:
                val = 0;
                break;
        case REGULATOR_MODE_FAST:
                val = RT5120_FPWM_MASK(rid);
                break;
        default:
                return -EINVAL;
        }

        return regmap_update_bits(regmap, RT5120_REG_MODECTL, mask, val);
}

static unsigned int rt5120_buck_get_mode(struct regulator_dev *rdev)
{
        struct regmap *regmap = rdev_get_regmap(rdev);
        int ret, rid = rdev_get_id(rdev);
        unsigned int val;

        ret = regmap_read(regmap, RT5120_REG_MODECTL, &val);
        if (ret)
                return REGULATOR_MODE_INVALID;

        if (val & RT5120_FPWM_MASK(rid))
                return REGULATOR_MODE_FAST;

        return REGULATOR_MODE_NORMAL;
}

static int rt5120_regulator_get_error_flags(struct regulator_dev *rdev,
                                            unsigned int *flags)
{
        struct regmap *regmap = rdev_get_regmap(rdev);
        unsigned int stat, hd_stat, cur_flags = 0;
        int rid = rdev_get_id(rdev), ret;

        /*
         * reg 0x03/0x04/0x05 to indicate PG/UV/OV
         * use block read to descrease I/O xfer time
         */
        ret = regmap_raw_read(regmap, RT5120_REG_PGSTAT, &stat, 3);
        if (ret)
                return ret;

        ret = regmap_read(regmap, RT5120_REG_INTSTAT, &hd_stat);
        if (ret)
                return ret;

        if (!(stat & RT5120_OUTPG_MASK(rid))) {
                if (stat & RT5120_OUTUV_MASK(rid))
                        cur_flags |= REGULATOR_ERROR_UNDER_VOLTAGE;

                if (stat & RT5120_OUTOV_MASK(rid))
                        cur_flags |= REGULATOR_ERROR_REGULATION_OUT;
        }

        if (hd_stat & RT5120_HOTDIE_MASK)
                cur_flags |= REGULATOR_ERROR_OVER_TEMP;

        *flags = cur_flags;
        return 0;
}

static int rt5120_buck1_set_suspend_voltage(struct regulator_dev *rdev, int uV)
{
        struct regmap *regmap = rdev_get_regmap(rdev);
        int sel;

        if (uV < RT5120_BUCK1_MINUV || uV > RT5120_BUCK1_MAXUV)
                return -EINVAL;

        sel = (uV - RT5120_BUCK1_MINUV) / RT5120_BUCK1_STEPUV;
        return regmap_write(regmap, RT5120_REG_CH1SLPVID, sel);
}

static int rt5120_regulator_set_suspend_enable(struct regulator_dev *rdev)
{
        struct regmap *regmap = rdev_get_regmap(rdev);
        int rid = rdev_get_id(rdev);
        unsigned int mask = RT5120_RIDEN_MASK(rid);

        return regmap_update_bits(regmap, RT5120_REG_SLPCTL, mask, mask);
}

static int rt5120_regulator_set_suspend_disable(struct regulator_dev *rdev)
{
        struct regmap *regmap = rdev_get_regmap(rdev);
        int rid = rdev_get_id(rdev);
        unsigned int mask = RT5120_RIDEN_MASK(rid);

        return regmap_update_bits(regmap, RT5120_REG_SLPCTL, mask, 0);
}

static const struct regulator_ops rt5120_buck1_ops = {
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .is_enabled = regulator_is_enabled_regmap,
        .list_voltage = regulator_list_voltage_linear,
        .set_voltage_sel = regulator_set_voltage_sel_regmap,
        .get_voltage_sel = regulator_get_voltage_sel_regmap,
        .set_active_discharge = regulator_set_active_discharge_regmap,
        .set_mode = rt5120_buck_set_mode,
        .get_mode = rt5120_buck_get_mode,
        .get_error_flags = rt5120_regulator_get_error_flags,
        .set_suspend_voltage = rt5120_buck1_set_suspend_voltage,
        .set_suspend_enable = rt5120_regulator_set_suspend_enable,
        .set_suspend_disable = rt5120_regulator_set_suspend_disable,
};

static const struct regulator_ops rt5120_buck234_ops = {
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .is_enabled = regulator_is_enabled_regmap,
        .set_active_discharge = regulator_set_active_discharge_regmap,
        .set_mode = rt5120_buck_set_mode,
        .get_mode = rt5120_buck_get_mode,
        .get_error_flags = rt5120_regulator_get_error_flags,
        .set_suspend_enable = rt5120_regulator_set_suspend_enable,
        .set_suspend_disable = rt5120_regulator_set_suspend_disable,
};

static const struct regulator_ops rt5120_ldo_ops = {
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .is_enabled = regulator_is_enabled_regmap,
        .set_active_discharge = regulator_set_active_discharge_regmap,
        .get_error_flags = rt5120_regulator_get_error_flags,
        .set_suspend_enable = rt5120_regulator_set_suspend_enable,
        .set_suspend_disable = rt5120_regulator_set_suspend_disable,
};

static const struct regulator_ops rt5120_exten_ops = {
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .is_enabled = regulator_is_enabled_regmap,
        .set_suspend_enable = rt5120_regulator_set_suspend_enable,
        .set_suspend_disable = rt5120_regulator_set_suspend_disable,
};

static unsigned int rt5120_buck_of_map_mode(unsigned int mode)
{
        switch (mode) {
        case RT5120_AUTO_MODE:
                return REGULATOR_MODE_NORMAL;
        case RT5120_FPWM_MODE:
                return REGULATOR_MODE_FAST;
        default:
                return REGULATOR_MODE_INVALID;
        }
}

static void rt5120_fillin_regulator_desc(struct regulator_desc *desc, int rid)
{
        static const char * const name[] = {
                "buck1", "buck2", "buck3", "buck4", "ldo", "exten" };
        static const char * const sname[] = {
                "vin1", "vin2", "vin3", "vin4", "vinldo", NULL };

        /* Common regulator property */
        desc->name = name[rid];
        desc->supply_name = sname[rid];
        desc->owner = THIS_MODULE;
        desc->type = REGULATOR_VOLTAGE;
        desc->id = rid;
        desc->enable_reg = RT5120_REG_ENABLE;
        desc->enable_mask = RT5120_RIDEN_MASK(rid);
        desc->active_discharge_reg = RT5120_REG_DISCHG;
        desc->active_discharge_mask = RT5120_RADEN_MASK(rid);
        desc->active_discharge_on = RT5120_RADEN_MASK(rid);
        /* Config n_voltages to 1 for all*/
        desc->n_voltages = 1;

        /* Only buck support mode change */
        if (rid >= RT5120_REGULATOR_BUCK1 && rid <= RT5120_REGULATOR_BUCK4)
                desc->of_map_mode = rt5120_buck_of_map_mode;

        /* RID specific property init */
        switch (rid) {
        case RT5120_REGULATOR_BUCK1:
                /* Only buck1 support voltage change by I2C */
                desc->n_voltages = RT5120_BUCK1_NUM_VOLT;
                desc->min_uV = RT5120_BUCK1_MINUV;
                desc->uV_step = RT5120_BUCK1_STEPUV;
                desc->vsel_reg = RT5120_REG_CH1VID;
                desc->vsel_mask = RT5120_CH1VID_MASK;
                desc->ops = &rt5120_buck1_ops;
                break;
        case RT5120_REGULATOR_BUCK2 ... RT5120_REGULATOR_BUCK4:
                desc->ops = &rt5120_buck234_ops;
                break;
        case RT5120_REGULATOR_LDO:
                desc->ops = &rt5120_ldo_ops;
                break;
        default:
                desc->ops = &rt5120_exten_ops;
        }
}

static int rt5120_of_parse_cb(struct rt5120_priv *priv, int rid,
                              struct of_regulator_match *match)
{
        struct regulator_desc *desc = priv->rdesc + rid;
        struct regulator_init_data *init_data = match->init_data;

        if (!init_data || rid == RT5120_REGULATOR_BUCK1)
                return 0;

        if (init_data->constraints.min_uV != init_data->constraints.max_uV) {
                dev_err(priv->dev, "Variable voltage for fixed regulator\n");
                return -EINVAL;
        }

        desc->fixed_uV = init_data->constraints.min_uV;
        return 0;
}

static struct of_regulator_match rt5120_regu_match[RT5120_MAX_REGULATOR] = {
        [RT5120_REGULATOR_BUCK1] = { .name = "buck1", },
        [RT5120_REGULATOR_BUCK2] = { .name = "buck2", },
        [RT5120_REGULATOR_BUCK3] = { .name = "buck3", },
        [RT5120_REGULATOR_BUCK4] = { .name = "buck4", },
        [RT5120_REGULATOR_LDO] = { .name = "ldo", },
        [RT5120_REGULATOR_EXTEN] = { .name = "exten", }
};

static int rt5120_parse_regulator_dt_data(struct rt5120_priv *priv)
{
        struct device *dev = priv->dev->parent;
        struct device_node *reg_node;
        int i, ret;

        for (i = 0; i < RT5120_MAX_REGULATOR; i++) {
                rt5120_fillin_regulator_desc(priv->rdesc + i, i);

                rt5120_regu_match[i].desc = priv->rdesc + i;
        }

        reg_node = of_get_child_by_name(dev->of_node, "regulators");
        if (!reg_node) {
                dev_err(priv->dev, "Couldn't find 'regulators' node\n");
                return -ENODEV;
        }

        ret = of_regulator_match(priv->dev, reg_node, rt5120_regu_match,
                                 ARRAY_SIZE(rt5120_regu_match));

        of_node_put(reg_node);

        if (ret < 0) {
                dev_err(priv->dev,
                        "Error parsing regulator init data (%d)\n", ret);
                return ret;
        }

        for (i = 0; i < RT5120_MAX_REGULATOR; i++) {
                ret = rt5120_of_parse_cb(priv, i, rt5120_regu_match + i);
                if (ret) {
                        dev_err(priv->dev, "Failed in [%d] of_passe_cb\n", i);
                        return ret;
                }
        }

        return 0;
}

static int rt5120_device_property_init(struct rt5120_priv *priv)
{
        struct device *dev = priv->dev->parent;
        struct device_node *np = dev->of_node;
        bool prot_enable;
        unsigned int prot_enable_val = 0;

        /* Assign UV/OV HW protection behavior */
        prot_enable = of_property_read_bool(np,
                                            "richtek,enable-undervolt-hiccup");
        if (prot_enable)
                prot_enable_val |= RT5120_UVHICCUP_MASK;

        prot_enable = of_property_read_bool(np,
                                            "richtek,enable-overvolt-hiccup");
        if (prot_enable)
                prot_enable_val |= RT5120_OVHICCUP_MASK;

        return regmap_update_bits(priv->regmap, RT5120_REG_UVOVPROT,
                                  RT5120_UVHICCUP_MASK | RT5120_OVHICCUP_MASK,
                                  prot_enable_val);
}

static int rt5120_regulator_probe(struct platform_device *pdev)
{
        struct rt5120_priv *priv;
        struct regulator_dev *rdev;
        struct regulator_config config = {};
        int i, ret;

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

        priv->dev = &pdev->dev;

        priv->regmap = dev_get_regmap(pdev->dev.parent, NULL);
        if (!priv->regmap) {
                dev_err(&pdev->dev, "Failed to init regmap\n");
                return -ENODEV;
        }

        ret = rt5120_device_property_init(priv);
        if (ret) {
                dev_err(&pdev->dev, "Failed to do property init\n");
                return ret;
        }

        ret = rt5120_parse_regulator_dt_data(priv);
        if (ret) {
                dev_err(&pdev->dev, "Failed to parse dt data\n");
                return ret;
        }

        config.dev = &pdev->dev;
        config.regmap = priv->regmap;

        for (i = 0; i < RT5120_MAX_REGULATOR; i++) {
                config.of_node = rt5120_regu_match[i].of_node;
                config.init_data = rt5120_regu_match[i].init_data;

                rdev = devm_regulator_register(&pdev->dev, priv->rdesc + i,
                                               &config);
                if (IS_ERR(rdev)) {
                        dev_err(&pdev->dev,
                                "Failed to register regulator [%d]\n", i);
                        return PTR_ERR(rdev);
                }
        }

        return 0;
}

static const struct platform_device_id rt5120_regulator_dev_table[] = {
        { "rt5120-regulator", 0 },
        {}
};
MODULE_DEVICE_TABLE(platform, rt5120_regulator_dev_table);

static struct platform_driver rt5120_regulator_driver = {
        .driver = {
                .name = "rt5120-regulator",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
        .id_table = rt5120_regulator_dev_table,
        .probe = rt5120_regulator_probe,
};
module_platform_driver(rt5120_regulator_driver);

MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
MODULE_DESCRIPTION("Richtek RT5120 regulator driver");
MODULE_LICENSE("GPL v2");