root/drivers/regulator/mt6370-regulator.c
// SPDX-License-Identifier: GPL-2.0+

#include <linux/bits.h>
#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.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>

enum {
        MT6370_IDX_DSVBOOST = 0,
        MT6370_IDX_DSVPOS,
        MT6370_IDX_DSVNEG,
        MT6370_IDX_VIBLDO,
        MT6370_MAX_IDX
};

#define MT6370_REG_LDO_CFG      0x180
#define MT6370_REG_LDO_VOUT     0x181
#define MT6370_REG_DB_CTRL1     0x1B0
#define MT6370_REG_DB_CTRL2     0x1B1
#define MT6370_REG_DB_VBST      0x1B2
#define MT6370_REG_DB_VPOS      0x1B3
#define MT6370_REG_DB_VNEG      0x1B4
#define MT6370_REG_LDO_STAT     0x1DC
#define MT6370_REG_DB_STAT      0x1DF

#define MT6370_LDOOMS_MASK      BIT(7)
#define MT6370_LDOEN_MASK       BIT(7)
#define MT6370_LDOVOUT_MASK     GENMASK(3, 0)
#define MT6370_DBPERD_MASK      (BIT(7) | BIT(4))
#define MT6370_DBEXTEN_MASK     BIT(0)
#define MT6370_DBVPOSEN_MASK    BIT(6)
#define MT6370_DBVPOSDISG_MASK  BIT(5)
#define MT6370_DBVNEGEN_MASK    BIT(3)
#define MT6370_DBVNEGDISG_MASK  BIT(2)
#define MT6370_DBALLON_MASK     (MT6370_DBVPOSEN_MASK | MT6370_DBVNEGEN_MASK)
#define MT6370_DBSLEW_MASK      GENMASK(7, 6)
#define MT6370_DBVOUT_MASK      GENMASK(5, 0)
#define MT6370_LDOOC_EVT_MASK   BIT(7)
#define MT6370_POSSCP_EVT_MASK  BIT(7)
#define MT6370_NEGSCP_EVT_MASK  BIT(6)
#define MT6370_BSTOCP_EVT_MASK  BIT(5)
#define MT6370_POSOCP_EVT_MASK  BIT(4)
#define MT6370_NEGOCP_EVT_MASK  BIT(3)

#define MT6370_LDO_MINUV        1600000
#define MT6370_LDO_STPUV        200000
#define MT6370_LDO_N_VOLT       13
#define MT6370_DBVBOOST_MINUV   4000000
#define MT6370_DBVBOOST_STPUV   50000
#define MT6370_DBVBOOST_N_VOLT  45
#define MT6370_DBVOUT_MINUV     4000000
#define MT6370_DBVOUT_STPUV     50000
#define MT6370_DBVOUT_N_VOLT    41

struct mt6370_priv {
        struct device *dev;
        struct regmap *regmap;
        struct regulator_dev *rdev[MT6370_MAX_IDX];
        bool use_external_ctrl;
};

static const unsigned int mt6370_vpos_ramp_tbl[] = { 8540, 5840, 4830, 3000 };
static const unsigned int mt6370_vneg_ramp_tbl[] = { 10090, 6310, 5050, 3150 };

static int mt6370_get_error_flags(struct regulator_dev *rdev,
                                  unsigned int *flags)
{
        struct regmap *regmap = rdev_get_regmap(rdev);
        unsigned int stat_reg, stat, rpt_flags = 0;
        int rid = rdev_get_id(rdev), ret;

        if (rid == MT6370_IDX_VIBLDO)
                stat_reg = MT6370_REG_LDO_STAT;
        else
                stat_reg = MT6370_REG_DB_STAT;

        ret = regmap_read(regmap, stat_reg, &stat);
        if (ret)
                return ret;

        switch (rid) {
        case MT6370_IDX_DSVBOOST:
                if (stat & MT6370_BSTOCP_EVT_MASK)
                        rpt_flags |= REGULATOR_ERROR_OVER_CURRENT;
                break;
        case MT6370_IDX_DSVPOS:
                if (stat & MT6370_POSSCP_EVT_MASK)
                        rpt_flags |= REGULATOR_ERROR_UNDER_VOLTAGE;

                if (stat & MT6370_POSOCP_EVT_MASK)
                        rpt_flags |= REGULATOR_ERROR_OVER_CURRENT;
                break;
        case MT6370_IDX_DSVNEG:
                if (stat & MT6370_NEGSCP_EVT_MASK)
                        rpt_flags |= REGULATOR_ERROR_UNDER_VOLTAGE;

                if (stat & MT6370_NEGOCP_EVT_MASK)
                        rpt_flags |= REGULATOR_ERROR_OVER_CURRENT;
                break;
        default:
                if (stat & MT6370_LDOOC_EVT_MASK)
                        rpt_flags |= REGULATOR_ERROR_OVER_CURRENT;
                break;
        }

        *flags = rpt_flags;
        return 0;
}

static const struct regulator_ops mt6370_dbvboost_ops = {
        .get_voltage_sel = regulator_get_voltage_sel_regmap,
        .set_voltage_sel = regulator_set_voltage_sel_regmap,
        .list_voltage = regulator_list_voltage_linear,
        .get_bypass = regulator_get_bypass_regmap,
        .set_bypass = regulator_set_bypass_regmap,
        .get_error_flags = mt6370_get_error_flags,
};

static const struct regulator_ops mt6370_dbvout_ops = {
        .get_voltage_sel = regulator_get_voltage_sel_regmap,
        .set_voltage_sel = regulator_set_voltage_sel_regmap,
        .list_voltage = regulator_list_voltage_linear,
        .is_enabled = regulator_is_enabled_regmap,
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .set_active_discharge = regulator_set_active_discharge_regmap,
        .set_ramp_delay = regulator_set_ramp_delay_regmap,
        .get_error_flags = mt6370_get_error_flags,
};

static const struct regulator_ops mt6370_ldo_ops = {
        .get_voltage_sel = regulator_get_voltage_sel_regmap,
        .set_voltage_sel = regulator_set_voltage_sel_regmap,
        .list_voltage = regulator_list_voltage_linear,
        .is_enabled = regulator_is_enabled_regmap,
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .set_active_discharge = regulator_set_active_discharge_regmap,
        .get_error_flags = mt6370_get_error_flags,
};

static int mt6370_of_parse_cb(struct device_node *np,
                              const struct regulator_desc *desc,
                              struct regulator_config *config)
{
        struct mt6370_priv *priv = config->driver_data;
        struct gpio_desc *enable_gpio;
        int ret;

        enable_gpio = fwnode_gpiod_get_index(of_fwnode_handle(np), "enable", 0,
                                             GPIOD_OUT_HIGH |
                                             GPIOD_FLAGS_BIT_NONEXCLUSIVE,
                                             desc->name);
        if (IS_ERR(enable_gpio)) {
                config->ena_gpiod = NULL;
                return 0;
        }

        /*
         * RG control by default
         * Only if all are using external pin, change all by external control
         */
        if (priv->use_external_ctrl) {
                ret = regmap_update_bits(priv->regmap, MT6370_REG_DB_CTRL1,
                                         MT6370_DBEXTEN_MASK,
                                         MT6370_DBEXTEN_MASK);
                if (ret)
                        return ret;
        }

        config->ena_gpiod = enable_gpio;
        priv->use_external_ctrl = true;
        return 0;
}

static const struct regulator_desc mt6370_regulator_descs[] = {
        {
                .name = "mt6370-dsv-vbst",
                .of_match = of_match_ptr("dsvbst"),
                .regulators_node = of_match_ptr("regulators"),
                .id = MT6370_IDX_DSVBOOST,
                .type = REGULATOR_VOLTAGE,
                .owner = THIS_MODULE,
                .ops = &mt6370_dbvboost_ops,
                .min_uV = MT6370_DBVBOOST_MINUV,
                .uV_step = MT6370_DBVBOOST_STPUV,
                .n_voltages = MT6370_DBVBOOST_N_VOLT,
                .vsel_reg = MT6370_REG_DB_VBST,
                .vsel_mask = MT6370_DBVOUT_MASK,
                .bypass_reg = MT6370_REG_DB_CTRL1,
                .bypass_mask = MT6370_DBPERD_MASK,
                .bypass_val_on = MT6370_DBPERD_MASK,
        },
        {
                .name = "mt6370-dsv-vpos",
                .of_match = of_match_ptr("dsvpos"),
                .regulators_node = of_match_ptr("regulators"),
                .id = MT6370_IDX_DSVPOS,
                .type = REGULATOR_VOLTAGE,
                .owner = THIS_MODULE,
                .of_parse_cb = mt6370_of_parse_cb,
                .ops = &mt6370_dbvout_ops,
                .min_uV = MT6370_DBVOUT_MINUV,
                .uV_step = MT6370_DBVOUT_STPUV,
                .n_voltages = MT6370_DBVOUT_N_VOLT,
                .vsel_reg = MT6370_REG_DB_VPOS,
                .vsel_mask = MT6370_DBVOUT_MASK,
                .enable_reg = MT6370_REG_DB_CTRL2,
                .enable_mask = MT6370_DBVPOSEN_MASK,
                .ramp_reg = MT6370_REG_DB_VPOS,
                .ramp_mask = MT6370_DBSLEW_MASK,
                .ramp_delay_table = mt6370_vpos_ramp_tbl,
                .n_ramp_values = ARRAY_SIZE(mt6370_vpos_ramp_tbl),
                .active_discharge_reg = MT6370_REG_DB_CTRL2,
                .active_discharge_mask = MT6370_DBVPOSDISG_MASK,
                .active_discharge_on = MT6370_DBVPOSDISG_MASK,
        },
        {
                .name = "mt6370-dsv-vneg",
                .of_match = of_match_ptr("dsvneg"),
                .regulators_node = of_match_ptr("regulators"),
                .id = MT6370_IDX_DSVNEG,
                .type = REGULATOR_VOLTAGE,
                .owner = THIS_MODULE,
                .of_parse_cb = mt6370_of_parse_cb,
                .ops = &mt6370_dbvout_ops,
                .min_uV = MT6370_DBVOUT_MINUV,
                .uV_step = MT6370_DBVOUT_STPUV,
                .n_voltages = MT6370_DBVOUT_N_VOLT,
                .vsel_reg = MT6370_REG_DB_VNEG,
                .vsel_mask = MT6370_DBVOUT_MASK,
                .enable_reg = MT6370_REG_DB_CTRL2,
                .enable_mask = MT6370_DBVNEGEN_MASK,
                .ramp_reg = MT6370_REG_DB_VNEG,
                .ramp_mask = MT6370_DBSLEW_MASK,
                .ramp_delay_table = mt6370_vneg_ramp_tbl,
                .n_ramp_values = ARRAY_SIZE(mt6370_vneg_ramp_tbl),
                .active_discharge_reg = MT6370_REG_DB_CTRL2,
                .active_discharge_mask = MT6370_DBVNEGDISG_MASK,
                .active_discharge_on = MT6370_DBVNEGDISG_MASK,
        },
        {
                .name = "mt6370-vib-ldo",
                .of_match = of_match_ptr("vibldo"),
                .regulators_node = of_match_ptr("regulators"),
                .id = MT6370_IDX_VIBLDO,
                .type = REGULATOR_VOLTAGE,
                .owner = THIS_MODULE,
                .ops = &mt6370_ldo_ops,
                .min_uV = MT6370_LDO_MINUV,
                .uV_step = MT6370_LDO_STPUV,
                .n_voltages = MT6370_LDO_N_VOLT,
                .vsel_reg = MT6370_REG_LDO_VOUT,
                .vsel_mask = MT6370_LDOVOUT_MASK,
                .enable_reg = MT6370_REG_LDO_VOUT,
                .enable_mask = MT6370_LDOEN_MASK,
                .active_discharge_reg = MT6370_REG_LDO_CFG,
                .active_discharge_mask = MT6370_LDOOMS_MASK,
                .active_discharge_on = MT6370_LDOOMS_MASK,
        }
};

static irqreturn_t mt6370_scp_handler(int irq, void *data)
{
        struct regulator_dev *rdev = data;

        regulator_notifier_call_chain(rdev, REGULATOR_EVENT_UNDER_VOLTAGE,
                                      NULL);
        return IRQ_HANDLED;
}

static irqreturn_t mt6370_ocp_handler(int irq, void *data)
{
        struct regulator_dev *rdev = data;

        regulator_notifier_call_chain(rdev, REGULATOR_EVENT_OVER_CURRENT, NULL);
        return IRQ_HANDLED;
}

static int mt6370_regulator_irq_register(struct mt6370_priv *priv)
{
        struct platform_device *pdev = to_platform_device(priv->dev);
        static const struct {
                const char *name;
                int rid;
                irq_handler_t handler;
        } mt6370_irqs[] = {
                { "db_vpos_scp", MT6370_IDX_DSVPOS, mt6370_scp_handler },
                { "db_vneg_scp", MT6370_IDX_DSVNEG, mt6370_scp_handler },
                { "db_vbst_ocp", MT6370_IDX_DSVBOOST, mt6370_ocp_handler },
                { "db_vpos_ocp", MT6370_IDX_DSVPOS,  mt6370_ocp_handler },
                { "db_vneg_ocp", MT6370_IDX_DSVNEG, mt6370_ocp_handler },
                { "ldo_oc", MT6370_IDX_VIBLDO, mt6370_ocp_handler }
        };
        struct regulator_dev *rdev;
        int i, irq, ret;

        for (i = 0; i < ARRAY_SIZE(mt6370_irqs); i++) {
                irq = platform_get_irq_byname(pdev, mt6370_irqs[i].name);

                rdev = priv->rdev[mt6370_irqs[i].rid];

                ret = devm_request_threaded_irq(priv->dev, irq, NULL,
                                                mt6370_irqs[i].handler, 0,
                                                mt6370_irqs[i].name, rdev);
                if (ret) {
                        dev_err(priv->dev,
                                "Failed to register (%d) interrupt\n", i);
                        return ret;
                }
        }

        return 0;
}

static int mt6370_regulator_register(struct mt6370_priv *priv)
{
        struct regulator_dev *rdev;
        struct regulator_config cfg = {};
        struct device *parent = priv->dev->parent;
        int i;

        cfg.dev = parent;
        cfg.driver_data = priv;

        for (i = 0; i < MT6370_MAX_IDX; i++) {
                rdev = devm_regulator_register(priv->dev,
                                               mt6370_regulator_descs + i,
                                               &cfg);
                if (IS_ERR(rdev)) {
                        dev_err(priv->dev,
                                "Failed to register (%d) regulator\n", i);
                        return PTR_ERR(rdev);
                }

                priv->rdev[i] = rdev;
        }

        return 0;
}

static int mt6370_regulator_probe(struct platform_device *pdev)
{
        struct mt6370_priv *priv;
        int 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 = mt6370_regulator_register(priv);
        if (ret)
                return ret;

        return mt6370_regulator_irq_register(priv);
}

static const struct platform_device_id mt6370_devid_table[] = {
        { "mt6370-regulator", 0},
        {}
};
MODULE_DEVICE_TABLE(platform, mt6370_devid_table);

static struct platform_driver mt6370_regulator_driver = {
        .driver = {
                .name = "mt6370-regulator",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
        .id_table = mt6370_devid_table,
        .probe = mt6370_regulator_probe,
};
module_platform_driver(mt6370_regulator_driver);

MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
MODULE_DESCRIPTION("Mediatek MT6370 Regulator Driver");
MODULE_LICENSE("GPL v2");