root/drivers/regulator/wm831x-dcdc.c
// SPDX-License-Identifier: GPL-2.0+
//
// wm831x-dcdc.c  --  DC-DC buck converter driver for the WM831x series
//
// Copyright 2009 Wolfson Microelectronics PLC.
//
// Author: Mark Brown <broonie@opensource.wolfsonmicro.com>

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/gpio/consumer.h>
#include <linux/slab.h>

#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/regulator.h>
#include <linux/mfd/wm831x/pdata.h>

#define WM831X_BUCKV_MAX_SELECTOR 0x68
#define WM831X_BUCKP_MAX_SELECTOR 0x66

#define WM831X_DCDC_MODE_FAST    0
#define WM831X_DCDC_MODE_NORMAL  1
#define WM831X_DCDC_MODE_IDLE    2
#define WM831X_DCDC_MODE_STANDBY 3

#define WM831X_DCDC_MAX_NAME 9

/* Register offsets in control block */
#define WM831X_DCDC_CONTROL_1     0
#define WM831X_DCDC_CONTROL_2     1
#define WM831X_DCDC_ON_CONFIG     2
#define WM831X_DCDC_SLEEP_CONTROL 3
#define WM831X_DCDC_DVS_CONTROL   4

/*
 * Shared
 */

struct wm831x_dcdc {
        char name[WM831X_DCDC_MAX_NAME];
        char supply_name[WM831X_DCDC_MAX_NAME];
        struct regulator_desc desc;
        int base;
        struct wm831x *wm831x;
        struct regulator_dev *regulator;
        struct gpio_desc *dvs_gpiod;
        int dvs_gpio_state;
        int on_vsel;
        int dvs_vsel;
};

static unsigned int wm831x_dcdc_get_mode(struct regulator_dev *rdev)

{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
        struct wm831x *wm831x = dcdc->wm831x;
        u16 reg = dcdc->base + WM831X_DCDC_ON_CONFIG;
        int val;

        val = wm831x_reg_read(wm831x, reg);
        if (val < 0)
                return val;

        val = (val & WM831X_DC1_ON_MODE_MASK) >> WM831X_DC1_ON_MODE_SHIFT;

        switch (val) {
        case WM831X_DCDC_MODE_FAST:
                return REGULATOR_MODE_FAST;
        case WM831X_DCDC_MODE_NORMAL:
                return REGULATOR_MODE_NORMAL;
        case WM831X_DCDC_MODE_STANDBY:
                return REGULATOR_MODE_STANDBY;
        case WM831X_DCDC_MODE_IDLE:
                return REGULATOR_MODE_IDLE;
        default:
                BUG();
                return -EINVAL;
        }
}

static int wm831x_dcdc_set_mode_int(struct wm831x *wm831x, int reg,
                                    unsigned int mode)
{
        int val;

        switch (mode) {
        case REGULATOR_MODE_FAST:
                val = WM831X_DCDC_MODE_FAST;
                break;
        case REGULATOR_MODE_NORMAL:
                val = WM831X_DCDC_MODE_NORMAL;
                break;
        case REGULATOR_MODE_STANDBY:
                val = WM831X_DCDC_MODE_STANDBY;
                break;
        case REGULATOR_MODE_IDLE:
                val = WM831X_DCDC_MODE_IDLE;
                break;
        default:
                return -EINVAL;
        }

        return wm831x_set_bits(wm831x, reg, WM831X_DC1_ON_MODE_MASK,
                               val << WM831X_DC1_ON_MODE_SHIFT);
}

static int wm831x_dcdc_set_mode(struct regulator_dev *rdev, unsigned int mode)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
        struct wm831x *wm831x = dcdc->wm831x;
        u16 reg = dcdc->base + WM831X_DCDC_ON_CONFIG;

        return wm831x_dcdc_set_mode_int(wm831x, reg, mode);
}

static int wm831x_dcdc_set_suspend_mode(struct regulator_dev *rdev,
                                        unsigned int mode)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
        struct wm831x *wm831x = dcdc->wm831x;
        u16 reg = dcdc->base + WM831X_DCDC_SLEEP_CONTROL;

        return wm831x_dcdc_set_mode_int(wm831x, reg, mode);
}

static int wm831x_dcdc_get_status(struct regulator_dev *rdev)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
        struct wm831x *wm831x = dcdc->wm831x;
        int ret;

        /* First, check for errors */
        ret = wm831x_reg_read(wm831x, WM831X_DCDC_UV_STATUS);
        if (ret < 0)
                return ret;

        if (ret & (1 << rdev_get_id(rdev))) {
                dev_dbg(wm831x->dev, "DCDC%d under voltage\n",
                        rdev_get_id(rdev) + 1);
                return REGULATOR_STATUS_ERROR;
        }

        /* DCDC1 and DCDC2 can additionally detect high voltage/current */
        if (rdev_get_id(rdev) < 2) {
                if (ret & (WM831X_DC1_OV_STS << rdev_get_id(rdev))) {
                        dev_dbg(wm831x->dev, "DCDC%d over voltage\n",
                                rdev_get_id(rdev) + 1);
                        return REGULATOR_STATUS_ERROR;
                }

                if (ret & (WM831X_DC1_HC_STS << rdev_get_id(rdev))) {
                        dev_dbg(wm831x->dev, "DCDC%d over current\n",
                                rdev_get_id(rdev) + 1);
                        return REGULATOR_STATUS_ERROR;
                }
        }

        /* Is the regulator on? */
        ret = wm831x_reg_read(wm831x, WM831X_DCDC_STATUS);
        if (ret < 0)
                return ret;
        if (!(ret & (1 << rdev_get_id(rdev))))
                return REGULATOR_STATUS_OFF;

        /* TODO: When we handle hardware control modes so we can report the
         * current mode. */
        return REGULATOR_STATUS_ON;
}

static irqreturn_t wm831x_dcdc_uv_irq(int irq, void *data)
{
        struct wm831x_dcdc *dcdc = data;

        regulator_notifier_call_chain(dcdc->regulator,
                                      REGULATOR_EVENT_UNDER_VOLTAGE,
                                      NULL);

        return IRQ_HANDLED;
}

static irqreturn_t wm831x_dcdc_oc_irq(int irq, void *data)
{
        struct wm831x_dcdc *dcdc = data;

        regulator_notifier_call_chain(dcdc->regulator,
                                      REGULATOR_EVENT_OVER_CURRENT,
                                      NULL);

        return IRQ_HANDLED;
}

/*
 * BUCKV specifics
 */

static const struct linear_range wm831x_buckv_ranges[] = {
        REGULATOR_LINEAR_RANGE(600000, 0, 0x7, 0),
        REGULATOR_LINEAR_RANGE(600000, 0x8, 0x68, 12500),
};

static int wm831x_buckv_set_dvs(struct regulator_dev *rdev, int state)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);

        if (state == dcdc->dvs_gpio_state)
                return 0;

        dcdc->dvs_gpio_state = state;
        gpiod_set_value(dcdc->dvs_gpiod, state);

        /* Should wait for DVS state change to be asserted if we have
         * a GPIO for it, for now assume the device is configured
         * for the fastest possible transition.
         */

        return 0;
}

static int wm831x_buckv_set_voltage_sel(struct regulator_dev *rdev,
                                        unsigned vsel)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
        struct wm831x *wm831x = dcdc->wm831x;
        int on_reg = dcdc->base + WM831X_DCDC_ON_CONFIG;
        int dvs_reg = dcdc->base + WM831X_DCDC_DVS_CONTROL;
        int ret;

        /* If this value is already set then do a GPIO update if we can */
        if (dcdc->dvs_gpiod && dcdc->on_vsel == vsel)
                return wm831x_buckv_set_dvs(rdev, 0);

        if (dcdc->dvs_gpiod && dcdc->dvs_vsel == vsel)
                return wm831x_buckv_set_dvs(rdev, 1);

        /* Always set the ON status to the minimum voltage */
        ret = wm831x_set_bits(wm831x, on_reg, WM831X_DC1_ON_VSEL_MASK, vsel);
        if (ret < 0)
                return ret;
        dcdc->on_vsel = vsel;

        if (!dcdc->dvs_gpiod)
                return ret;

        /* Kick the voltage transition now */
        ret = wm831x_buckv_set_dvs(rdev, 0);
        if (ret < 0)
                return ret;

        /*
         * If this VSEL is higher than the last one we've seen then
         * remember it as the DVS VSEL.  This is optimised for CPUfreq
         * usage where we want to get to the highest voltage very
         * quickly.
         */
        if (vsel > dcdc->dvs_vsel) {
                ret = wm831x_set_bits(wm831x, dvs_reg,
                                      WM831X_DC1_DVS_VSEL_MASK,
                                      vsel);
                if (ret == 0)
                        dcdc->dvs_vsel = vsel;
                else
                        dev_warn(wm831x->dev,
                                 "Failed to set DCDC DVS VSEL: %d\n", ret);
        }

        return 0;
}

static int wm831x_buckv_set_suspend_voltage(struct regulator_dev *rdev,
                                            int uV)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
        struct wm831x *wm831x = dcdc->wm831x;
        u16 reg = dcdc->base + WM831X_DCDC_SLEEP_CONTROL;
        int vsel;

        vsel = regulator_map_voltage_linear_range(rdev, uV, uV);
        if (vsel < 0)
                return vsel;

        return wm831x_set_bits(wm831x, reg, WM831X_DC1_SLP_VSEL_MASK, vsel);
}

static int wm831x_buckv_get_voltage_sel(struct regulator_dev *rdev)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);

        if (dcdc->dvs_gpiod && dcdc->dvs_gpio_state)
                return dcdc->dvs_vsel;
        else
                return dcdc->on_vsel;
}

/* Current limit options */
static const unsigned int wm831x_dcdc_ilim[] = {
        125000, 250000, 375000, 500000, 625000, 750000, 875000, 1000000
};

static const struct regulator_ops wm831x_buckv_ops = {
        .set_voltage_sel = wm831x_buckv_set_voltage_sel,
        .get_voltage_sel = wm831x_buckv_get_voltage_sel,
        .list_voltage = regulator_list_voltage_linear_range,
        .map_voltage = regulator_map_voltage_linear_range,
        .set_suspend_voltage = wm831x_buckv_set_suspend_voltage,
        .set_current_limit = regulator_set_current_limit_regmap,
        .get_current_limit = regulator_get_current_limit_regmap,

        .is_enabled = regulator_is_enabled_regmap,
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .get_status = wm831x_dcdc_get_status,
        .get_mode = wm831x_dcdc_get_mode,
        .set_mode = wm831x_dcdc_set_mode,
        .set_suspend_mode = wm831x_dcdc_set_suspend_mode,
};

/*
 * Set up DVS control.  We just log errors since we can still run
 * (with reduced performance) if we fail.
 */
static void wm831x_buckv_dvs_init(struct platform_device *pdev,
                                  struct wm831x_dcdc *dcdc,
                                  struct wm831x_buckv_pdata *pdata)
{
        struct wm831x *wm831x = dcdc->wm831x;
        int ret;
        u16 ctrl;

        if (!pdata)
                return;

        /* gpiolib won't let us read the GPIO status so pick the higher
         * of the two existing voltages so we take it as platform data.
         */
        dcdc->dvs_gpio_state = pdata->dvs_init_state;

        dcdc->dvs_gpiod = devm_gpiod_get(&pdev->dev, "dvs",
                        dcdc->dvs_gpio_state ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW);
        if (IS_ERR(dcdc->dvs_gpiod)) {
                dev_err(wm831x->dev, "Failed to get %s DVS GPIO: %ld\n",
                        dcdc->name, PTR_ERR(dcdc->dvs_gpiod));
                return;
        }

        switch (pdata->dvs_control_src) {
        case 1:
                ctrl = 2 << WM831X_DC1_DVS_SRC_SHIFT;
                break;
        case 2:
                ctrl = 3 << WM831X_DC1_DVS_SRC_SHIFT;
                break;
        default:
                dev_err(wm831x->dev, "Invalid DVS control source %d for %s\n",
                        pdata->dvs_control_src, dcdc->name);
                return;
        }

        /* If DVS_VSEL is set to the minimum value then raise it to ON_VSEL
         * to make bootstrapping a bit smoother.
         */
        if (!dcdc->dvs_vsel) {
                ret = wm831x_set_bits(wm831x,
                                      dcdc->base + WM831X_DCDC_DVS_CONTROL,
                                      WM831X_DC1_DVS_VSEL_MASK, dcdc->on_vsel);
                if (ret == 0)
                        dcdc->dvs_vsel = dcdc->on_vsel;
                else
                        dev_warn(wm831x->dev, "Failed to set DVS_VSEL: %d\n",
                                 ret);
        }

        ret = wm831x_set_bits(wm831x, dcdc->base + WM831X_DCDC_DVS_CONTROL,
                              WM831X_DC1_DVS_SRC_MASK, ctrl);
        if (ret < 0) {
                dev_err(wm831x->dev, "Failed to set %s DVS source: %d\n",
                        dcdc->name, ret);
        }
}

static int wm831x_buckv_probe(struct platform_device *pdev)
{
        struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
        struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
        struct regulator_config config = { };
        int id;
        struct wm831x_dcdc *dcdc;
        struct resource *res;
        int ret, irq;

        if (pdata && pdata->wm831x_num)
                id = (pdata->wm831x_num * 10) + 1;
        else
                id = 0;
        id = pdev->id - id;

        dev_dbg(&pdev->dev, "Probing DCDC%d\n", id + 1);

        dcdc = devm_kzalloc(&pdev->dev,  sizeof(struct wm831x_dcdc),
                            GFP_KERNEL);
        if (!dcdc)
                return -ENOMEM;

        dcdc->wm831x = wm831x;

        res = platform_get_resource(pdev, IORESOURCE_REG, 0);
        if (res == NULL) {
                dev_err(&pdev->dev, "No REG resource\n");
                ret = -EINVAL;
                goto err;
        }
        dcdc->base = res->start;

        snprintf(dcdc->name, sizeof(dcdc->name), "DCDC%d", id + 1);
        dcdc->desc.name = dcdc->name;

        snprintf(dcdc->supply_name, sizeof(dcdc->supply_name),
                 "DC%dVDD", id + 1);
        dcdc->desc.supply_name = dcdc->supply_name;

        dcdc->desc.id = id;
        dcdc->desc.type = REGULATOR_VOLTAGE;
        dcdc->desc.n_voltages = WM831X_BUCKV_MAX_SELECTOR + 1;
        dcdc->desc.linear_ranges = wm831x_buckv_ranges;
        dcdc->desc.n_linear_ranges = ARRAY_SIZE(wm831x_buckv_ranges);
        dcdc->desc.ops = &wm831x_buckv_ops;
        dcdc->desc.owner = THIS_MODULE;
        dcdc->desc.enable_reg = WM831X_DCDC_ENABLE;
        dcdc->desc.enable_mask = 1 << id;
        dcdc->desc.csel_reg = dcdc->base + WM831X_DCDC_CONTROL_2;
        dcdc->desc.csel_mask = WM831X_DC1_HC_THR_MASK;
        dcdc->desc.n_current_limits = ARRAY_SIZE(wm831x_dcdc_ilim);
        dcdc->desc.curr_table = wm831x_dcdc_ilim;

        ret = wm831x_reg_read(wm831x, dcdc->base + WM831X_DCDC_ON_CONFIG);
        if (ret < 0) {
                dev_err(wm831x->dev, "Failed to read ON VSEL: %d\n", ret);
                goto err;
        }
        dcdc->on_vsel = ret & WM831X_DC1_ON_VSEL_MASK;

        ret = wm831x_reg_read(wm831x, dcdc->base + WM831X_DCDC_DVS_CONTROL);
        if (ret < 0) {
                dev_err(wm831x->dev, "Failed to read DVS VSEL: %d\n", ret);
                goto err;
        }
        dcdc->dvs_vsel = ret & WM831X_DC1_DVS_VSEL_MASK;

        if (pdata && pdata->dcdc[id])
                wm831x_buckv_dvs_init(pdev, dcdc,
                                      pdata->dcdc[id]->driver_data);

        config.dev = pdev->dev.parent;
        if (pdata)
                config.init_data = pdata->dcdc[id];
        config.driver_data = dcdc;
        config.regmap = wm831x->regmap;

        dcdc->regulator = devm_regulator_register(&pdev->dev, &dcdc->desc,
                                                  &config);
        if (IS_ERR(dcdc->regulator)) {
                ret = PTR_ERR(dcdc->regulator);
                dev_err(wm831x->dev, "Failed to register DCDC%d: %d\n",
                        id + 1, ret);
                goto err;
        }

        irq = wm831x_irq(wm831x, platform_get_irq_byname(pdev, "UV"));
        ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
                                        wm831x_dcdc_uv_irq,
                                        IRQF_TRIGGER_RISING | IRQF_ONESHOT,
                                        dcdc->name, dcdc);
        if (ret != 0) {
                dev_err(&pdev->dev, "Failed to request UV IRQ %d: %d\n",
                        irq, ret);
                goto err;
        }

        irq = wm831x_irq(wm831x, platform_get_irq_byname(pdev, "HC"));
        ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
                                        wm831x_dcdc_oc_irq,
                                        IRQF_TRIGGER_RISING | IRQF_ONESHOT,
                                        dcdc->name, dcdc);
        if (ret != 0) {
                dev_err(&pdev->dev, "Failed to request HC IRQ %d: %d\n",
                        irq, ret);
                goto err;
        }

        platform_set_drvdata(pdev, dcdc);

        return 0;

err:
        return ret;
}

static struct platform_driver wm831x_buckv_driver = {
        .probe = wm831x_buckv_probe,
        .driver         = {
                .name   = "wm831x-buckv",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
};

/*
 * BUCKP specifics
 */

static int wm831x_buckp_set_suspend_voltage(struct regulator_dev *rdev, int uV)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
        struct wm831x *wm831x = dcdc->wm831x;
        u16 reg = dcdc->base + WM831X_DCDC_SLEEP_CONTROL;
        int sel;

        sel = regulator_map_voltage_linear(rdev, uV, uV);
        if (sel < 0)
                return sel;

        return wm831x_set_bits(wm831x, reg, WM831X_DC3_ON_VSEL_MASK, sel);
}

static const struct regulator_ops wm831x_buckp_ops = {
        .set_voltage_sel = regulator_set_voltage_sel_regmap,
        .get_voltage_sel = regulator_get_voltage_sel_regmap,
        .list_voltage = regulator_list_voltage_linear,
        .map_voltage = regulator_map_voltage_linear,
        .set_suspend_voltage = wm831x_buckp_set_suspend_voltage,

        .is_enabled = regulator_is_enabled_regmap,
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .get_status = wm831x_dcdc_get_status,
        .get_mode = wm831x_dcdc_get_mode,
        .set_mode = wm831x_dcdc_set_mode,
        .set_suspend_mode = wm831x_dcdc_set_suspend_mode,
};

static int wm831x_buckp_probe(struct platform_device *pdev)
{
        struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
        struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
        struct regulator_config config = { };
        int id;
        struct wm831x_dcdc *dcdc;
        struct resource *res;
        int ret, irq;

        if (pdata && pdata->wm831x_num)
                id = (pdata->wm831x_num * 10) + 1;
        else
                id = 0;
        id = pdev->id - id;

        dev_dbg(&pdev->dev, "Probing DCDC%d\n", id + 1);

        dcdc = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_dcdc),
                            GFP_KERNEL);
        if (!dcdc)
                return -ENOMEM;

        dcdc->wm831x = wm831x;

        res = platform_get_resource(pdev, IORESOURCE_REG, 0);
        if (res == NULL) {
                dev_err(&pdev->dev, "No REG resource\n");
                ret = -EINVAL;
                goto err;
        }
        dcdc->base = res->start;

        snprintf(dcdc->name, sizeof(dcdc->name), "DCDC%d", id + 1);
        dcdc->desc.name = dcdc->name;

        snprintf(dcdc->supply_name, sizeof(dcdc->supply_name),
                 "DC%dVDD", id + 1);
        dcdc->desc.supply_name = dcdc->supply_name;

        dcdc->desc.id = id;
        dcdc->desc.type = REGULATOR_VOLTAGE;
        dcdc->desc.n_voltages = WM831X_BUCKP_MAX_SELECTOR + 1;
        dcdc->desc.ops = &wm831x_buckp_ops;
        dcdc->desc.owner = THIS_MODULE;
        dcdc->desc.vsel_reg = dcdc->base + WM831X_DCDC_ON_CONFIG;
        dcdc->desc.vsel_mask = WM831X_DC3_ON_VSEL_MASK;
        dcdc->desc.enable_reg = WM831X_DCDC_ENABLE;
        dcdc->desc.enable_mask = 1 << id;
        dcdc->desc.min_uV = 850000;
        dcdc->desc.uV_step = 25000;

        config.dev = pdev->dev.parent;
        if (pdata)
                config.init_data = pdata->dcdc[id];
        config.driver_data = dcdc;
        config.regmap = wm831x->regmap;

        dcdc->regulator = devm_regulator_register(&pdev->dev, &dcdc->desc,
                                                  &config);
        if (IS_ERR(dcdc->regulator)) {
                ret = PTR_ERR(dcdc->regulator);
                dev_err(wm831x->dev, "Failed to register DCDC%d: %d\n",
                        id + 1, ret);
                goto err;
        }

        irq = wm831x_irq(wm831x, platform_get_irq_byname(pdev, "UV"));
        ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
                                        wm831x_dcdc_uv_irq,
                                        IRQF_TRIGGER_RISING | IRQF_ONESHOT,
                                        dcdc->name, dcdc);
        if (ret != 0) {
                dev_err(&pdev->dev, "Failed to request UV IRQ %d: %d\n",
                        irq, ret);
                goto err;
        }

        platform_set_drvdata(pdev, dcdc);

        return 0;

err:
        return ret;
}

static struct platform_driver wm831x_buckp_driver = {
        .probe = wm831x_buckp_probe,
        .driver         = {
                .name   = "wm831x-buckp",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
};

/*
 * DCDC boost convertors
 */

static int wm831x_boostp_get_status(struct regulator_dev *rdev)
{
        struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
        struct wm831x *wm831x = dcdc->wm831x;
        int ret;

        /* First, check for errors */
        ret = wm831x_reg_read(wm831x, WM831X_DCDC_UV_STATUS);
        if (ret < 0)
                return ret;

        if (ret & (1 << rdev_get_id(rdev))) {
                dev_dbg(wm831x->dev, "DCDC%d under voltage\n",
                        rdev_get_id(rdev) + 1);
                return REGULATOR_STATUS_ERROR;
        }

        /* Is the regulator on? */
        ret = wm831x_reg_read(wm831x, WM831X_DCDC_STATUS);
        if (ret < 0)
                return ret;
        if (ret & (1 << rdev_get_id(rdev)))
                return REGULATOR_STATUS_ON;
        else
                return REGULATOR_STATUS_OFF;
}

static const struct regulator_ops wm831x_boostp_ops = {
        .get_status = wm831x_boostp_get_status,

        .is_enabled = regulator_is_enabled_regmap,
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
};

static int wm831x_boostp_probe(struct platform_device *pdev)
{
        struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
        struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
        struct regulator_config config = { };
        int id = pdev->id % ARRAY_SIZE(pdata->dcdc);
        struct wm831x_dcdc *dcdc;
        struct resource *res;
        int ret, irq;

        dev_dbg(&pdev->dev, "Probing DCDC%d\n", id + 1);

        if (pdata == NULL || pdata->dcdc[id] == NULL)
                return -ENODEV;

        dcdc = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_dcdc), GFP_KERNEL);
        if (!dcdc)
                return -ENOMEM;

        dcdc->wm831x = wm831x;

        res = platform_get_resource(pdev, IORESOURCE_REG, 0);
        if (res == NULL) {
                dev_err(&pdev->dev, "No REG resource\n");
                return -EINVAL;
        }
        dcdc->base = res->start;

        snprintf(dcdc->name, sizeof(dcdc->name), "DCDC%d", id + 1);
        dcdc->desc.name = dcdc->name;
        dcdc->desc.id = id;
        dcdc->desc.type = REGULATOR_VOLTAGE;
        dcdc->desc.ops = &wm831x_boostp_ops;
        dcdc->desc.owner = THIS_MODULE;
        dcdc->desc.enable_reg = WM831X_DCDC_ENABLE;
        dcdc->desc.enable_mask = 1 << id;

        config.dev = pdev->dev.parent;
        if (pdata)
                config.init_data = pdata->dcdc[id];
        config.driver_data = dcdc;
        config.regmap = wm831x->regmap;

        dcdc->regulator = devm_regulator_register(&pdev->dev, &dcdc->desc,
                                                  &config);
        if (IS_ERR(dcdc->regulator)) {
                ret = PTR_ERR(dcdc->regulator);
                dev_err(wm831x->dev, "Failed to register DCDC%d: %d\n",
                        id + 1, ret);
                return ret;
        }

        irq = wm831x_irq(wm831x, platform_get_irq_byname(pdev, "UV"));
        ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
                                        wm831x_dcdc_uv_irq,
                                        IRQF_TRIGGER_RISING | IRQF_ONESHOT,
                                        dcdc->name,
                                        dcdc);
        if (ret != 0) {
                dev_err(&pdev->dev, "Failed to request UV IRQ %d: %d\n",
                        irq, ret);
                return ret;
        }

        platform_set_drvdata(pdev, dcdc);

        return 0;
}

static struct platform_driver wm831x_boostp_driver = {
        .probe = wm831x_boostp_probe,
        .driver         = {
                .name   = "wm831x-boostp",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
};

/*
 * External Power Enable
 *
 * These aren't actually DCDCs but look like them in hardware so share
 * code.
 */

#define WM831X_EPE_BASE 6

static const struct regulator_ops wm831x_epe_ops = {
        .is_enabled = regulator_is_enabled_regmap,
        .enable = regulator_enable_regmap,
        .disable = regulator_disable_regmap,
        .get_status = wm831x_dcdc_get_status,
};

static int wm831x_epe_probe(struct platform_device *pdev)
{
        struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
        struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
        struct regulator_config config = { };
        int id = pdev->id % ARRAY_SIZE(pdata->epe);
        struct wm831x_dcdc *dcdc;
        int ret;

        dev_dbg(&pdev->dev, "Probing EPE%d\n", id + 1);

        dcdc = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_dcdc), GFP_KERNEL);
        if (!dcdc)
                return -ENOMEM;

        dcdc->wm831x = wm831x;

        /* For current parts this is correct; probably need to revisit
         * in future.
         */
        snprintf(dcdc->name, sizeof(dcdc->name), "EPE%d", id + 1);
        dcdc->desc.name = dcdc->name;
        dcdc->desc.id = id + WM831X_EPE_BASE; /* Offset in DCDC registers */
        dcdc->desc.ops = &wm831x_epe_ops;
        dcdc->desc.type = REGULATOR_VOLTAGE;
        dcdc->desc.owner = THIS_MODULE;
        dcdc->desc.enable_reg = WM831X_DCDC_ENABLE;
        dcdc->desc.enable_mask = 1 << dcdc->desc.id;

        config.dev = pdev->dev.parent;
        if (pdata)
                config.init_data = pdata->epe[id];
        config.driver_data = dcdc;
        config.regmap = wm831x->regmap;

        dcdc->regulator = devm_regulator_register(&pdev->dev, &dcdc->desc,
                                                  &config);
        if (IS_ERR(dcdc->regulator)) {
                ret = PTR_ERR(dcdc->regulator);
                dev_err(wm831x->dev, "Failed to register EPE%d: %d\n",
                        id + 1, ret);
                goto err;
        }

        platform_set_drvdata(pdev, dcdc);

        return 0;

err:
        return ret;
}

static struct platform_driver wm831x_epe_driver = {
        .probe = wm831x_epe_probe,
        .driver         = {
                .name   = "wm831x-epe",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
};

static struct platform_driver * const drivers[] = {
        &wm831x_buckv_driver,
        &wm831x_buckp_driver,
        &wm831x_boostp_driver,
        &wm831x_epe_driver,
};

static int __init wm831x_dcdc_init(void)
{
        return platform_register_drivers(drivers, ARRAY_SIZE(drivers));
}
subsys_initcall(wm831x_dcdc_init);

static void __exit wm831x_dcdc_exit(void)
{
        platform_unregister_drivers(drivers, ARRAY_SIZE(drivers));
}
module_exit(wm831x_dcdc_exit);

/* Module information */
MODULE_AUTHOR("Mark Brown");
MODULE_DESCRIPTION("WM831x DC-DC convertor driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-buckv");
MODULE_ALIAS("platform:wm831x-buckp");
MODULE_ALIAS("platform:wm831x-boostp");
MODULE_ALIAS("platform:wm831x-epe");