/*
 * twl-regulator.c -- support regulators in twl4030/twl6030 family chips
 *
 * Copyright (C) 2008 David Brownell
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/mfd/twl.h>
#include <linux/delay.h>

/*
 * The TWL4030/TW5030/TPS659x0 family chips include power management, a
 * USB OTG transceiver, an RTC, ADC, PWM, and lots more.  Some versions
 * include an audio codec, battery charger, and more voltage regulators.
 * These chips are often used in OMAP-based systems.
 *
 * This driver implements software-based resource control for various
 * voltage regulators.  This is usually augmented with state machine
 * based control.
 */

struct twlreg_info {
        /* start of regulator's PM_RECEIVER control register bank */
        u8                      base;

        /* twl resource ID, for resource control state machine */
        u8                      id;

        /* voltage in mV = table[VSEL]; table_len must be a power-of-two */
        u8                      table_len;
        const u16               *table;

        /* State REMAP default configuration */
        u8                      remap;

        /* used by regulator core */
        struct regulator_desc   desc;

        /* chip specific features */
        unsigned long           features;

        /* data passed from board for external get/set voltage */
        void                    *data;
};


/* LDO control registers ... offset is from the base of its register bank.
 * The first three registers of all power resource banks help hardware to
 * manage the various resource groups.
 */
/* Common offset in TWL4030/6030 */
#define VREG_GRP                0
/* TWL4030 register offsets */
#define VREG_TYPE               1
#define VREG_REMAP              2
#define VREG_DEDICATED          3       /* LDO control */
#define VREG_VOLTAGE_SMPS_4030  9
/* TWL6030 register offsets */
#define VREG_TRANS              1
#define VREG_STATE              2
#define VREG_VOLTAGE            3
#define VREG_VOLTAGE_SMPS       4

static inline int
twlreg_read(struct twlreg_info *info, unsigned slave_subgp, unsigned offset)
{
        u8 value;
        int status;

        status = twl_i2c_read_u8(slave_subgp,
                        &value, info->base + offset);
        return (status < 0) ? status : value;
}

static inline int
twlreg_write(struct twlreg_info *info, unsigned slave_subgp, unsigned offset,
                                                 u8 value)
{
        return twl_i2c_write_u8(slave_subgp,
                        value, info->base + offset);
}

/*----------------------------------------------------------------------*/

/* generic power resource operations, which work on all regulators */

static int twlreg_grp(struct regulator_dev *rdev)
{
        return twlreg_read(rdev_get_drvdata(rdev), TWL_MODULE_PM_RECEIVER,
                                                                 VREG_GRP);
}

/*
 * Enable/disable regulators by joining/leaving the P1 (processor) group.
 * We assume nobody else is updating the DEV_GRP registers.
 */
/* definition for 4030 family */
#define P3_GRP_4030     BIT(7)          /* "peripherals" */
#define P2_GRP_4030     BIT(6)          /* secondary processor, modem, etc */
#define P1_GRP_4030     BIT(5)          /* CPU/Linux */
/* definition for 6030 family */
#define P3_GRP_6030     BIT(2)          /* secondary processor, modem, etc */
#define P2_GRP_6030     BIT(1)          /* "peripherals" */
#define P1_GRP_6030     BIT(0)          /* CPU/Linux */

static int twl4030reg_is_enabled(struct regulator_dev *rdev)
{
        int     state = twlreg_grp(rdev);

        if (state < 0)
                return state;

        return state & P1_GRP_4030;
}

#define PB_I2C_BUSY     BIT(0)
#define PB_I2C_BWEN     BIT(1)

/* Wait until buffer empty/ready to send a word on power bus. */
static int twl4030_wait_pb_ready(void)
{

        int     ret;
        int     timeout = 10;
        u8      val;

        do {
                ret = twl_i2c_read_u8(TWL_MODULE_PM_MASTER, &val,
                                      TWL4030_PM_MASTER_PB_CFG);
                if (ret < 0)
                        return ret;

                if (!(val & PB_I2C_BUSY))
                        return 0;

                mdelay(1);
                timeout--;
        } while (timeout);

        return -ETIMEDOUT;
}

/* Send a word over the powerbus */
static int twl4030_send_pb_msg(unsigned msg)
{
        u8      val;
        int     ret;

        /* save powerbus configuration */
        ret = twl_i2c_read_u8(TWL_MODULE_PM_MASTER, &val,
                              TWL4030_PM_MASTER_PB_CFG);
        if (ret < 0)
                return ret;

        /* Enable i2c access to powerbus */
        ret = twl_i2c_write_u8(TWL_MODULE_PM_MASTER, val | PB_I2C_BWEN,
                               TWL4030_PM_MASTER_PB_CFG);
        if (ret < 0)
                return ret;

        ret = twl4030_wait_pb_ready();
        if (ret < 0)
                return ret;

        ret = twl_i2c_write_u8(TWL_MODULE_PM_MASTER, msg >> 8,
                               TWL4030_PM_MASTER_PB_WORD_MSB);
        if (ret < 0)
                return ret;

        ret = twl_i2c_write_u8(TWL_MODULE_PM_MASTER, msg & 0xff,
                               TWL4030_PM_MASTER_PB_WORD_LSB);
        if (ret < 0)
                return ret;

        ret = twl4030_wait_pb_ready();
        if (ret < 0)
                return ret;

        /* Restore powerbus configuration */
        return twl_i2c_write_u8(TWL_MODULE_PM_MASTER, val,
                                TWL4030_PM_MASTER_PB_CFG);
}

static int twl4030reg_enable(struct regulator_dev *rdev)
{
        struct twlreg_info      *info = rdev_get_drvdata(rdev);
        int                     grp;
        int                     ret;

        grp = twlreg_grp(rdev);
        if (grp < 0)
                return grp;

        grp |= P1_GRP_4030;

        ret = twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_GRP, grp);

        return ret;
}

static int twl4030reg_disable(struct regulator_dev *rdev)
{
        struct twlreg_info      *info = rdev_get_drvdata(rdev);
        int                     grp;
        int                     ret;

        grp = twlreg_grp(rdev);
        if (grp < 0)
                return grp;

        grp &= ~(P1_GRP_4030 | P2_GRP_4030 | P3_GRP_4030);

        ret = twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_GRP, grp);

        return ret;
}

static int twl4030reg_get_status(struct regulator_dev *rdev)
{
        int     state = twlreg_grp(rdev);

        if (state < 0)
                return state;
        state &= 0x0f;

        /* assume state != WARM_RESET; we'd not be running...  */
        if (!state)
                return REGULATOR_STATUS_OFF;
        return (state & BIT(3))
                ? REGULATOR_STATUS_NORMAL
                : REGULATOR_STATUS_STANDBY;
}

static int twl4030reg_set_mode(struct regulator_dev *rdev, unsigned mode)
{
        struct twlreg_info      *info = rdev_get_drvdata(rdev);
        unsigned                message;

        /* We can only set the mode through state machine commands... */
        switch (mode) {
        case REGULATOR_MODE_NORMAL:
                message = MSG_SINGULAR(DEV_GRP_P1, info->id, RES_STATE_ACTIVE);
                break;
        case REGULATOR_MODE_STANDBY:
                message = MSG_SINGULAR(DEV_GRP_P1, info->id, RES_STATE_SLEEP);
                break;
        default:
                return -EINVAL;
        }

        return twl4030_send_pb_msg(message);
}

static inline unsigned int twl4030reg_map_mode(unsigned int mode)
{
        switch (mode) {
        case RES_STATE_ACTIVE:
                return REGULATOR_MODE_NORMAL;
        case RES_STATE_SLEEP:
                return REGULATOR_MODE_STANDBY;
        default:
                return REGULATOR_MODE_INVALID;
        }
}

/*----------------------------------------------------------------------*/

/*
 * Support for adjustable-voltage LDOs uses a four bit (or less) voltage
 * select field in its control register.   We use tables indexed by VSEL
 * to record voltages in milliVolts.  (Accuracy is about three percent.)
 *
 * Note that VSEL values for VAUX2 changed in twl5030 and newer silicon;
 * currently handled by listing two slightly different VAUX2 regulators,
 * only one of which will be configured.
 *
 * VSEL values documented as "TI cannot support these values" are flagged
 * in these tables as UNSUP() values; we normally won't assign them.
 *
 * VAUX3 at 3V is incorrectly listed in some TI manuals as unsupported.
 * TI are revising the twl5030/tps659x0 specs to support that 3.0V setting.
 */
#define UNSUP_MASK      0x8000

#define UNSUP(x)        (UNSUP_MASK | (x))
#define IS_UNSUP(info, x)                       \
        ((UNSUP_MASK & (x)) &&                  \
         !((info)->features & TWL4030_ALLOW_UNSUPPORTED))
#define LDO_MV(x)       (~UNSUP_MASK & (x))


static const u16 VAUX1_VSEL_table[] = {
        UNSUP(1500), UNSUP(1800), 2500, 2800,
        3000, 3000, 3000, 3000,
};
static const u16 VAUX2_4030_VSEL_table[] = {
        UNSUP(1000), UNSUP(1000), UNSUP(1200), 1300,
        1500, 1800, UNSUP(1850), 2500,
        UNSUP(2600), 2800, UNSUP(2850), UNSUP(3000),
        UNSUP(3150), UNSUP(3150), UNSUP(3150), UNSUP(3150),
};
static const u16 VAUX2_VSEL_table[] = {
        1700, 1700, 1900, 1300,
        1500, 1800, 2000, 2500,
        2100, 2800, 2200, 2300,
        2400, 2400, 2400, 2400,
};
static const u16 VAUX3_VSEL_table[] = {
        1500, 1800, 2500, 2800,
        3000, 3000, 3000, 3000,
};
static const u16 VAUX4_VSEL_table[] = {
        700, 1000, 1200, UNSUP(1300),
        1500, 1800, UNSUP(1850), 2500,
        UNSUP(2600), 2800, UNSUP(2850), UNSUP(3000),
        UNSUP(3150), UNSUP(3150), UNSUP(3150), UNSUP(3150),
};
static const u16 VMMC1_VSEL_table[] = {
        1850, 2850, 3000, 3150,
};
static const u16 VMMC2_VSEL_table[] = {
        UNSUP(1000), UNSUP(1000), UNSUP(1200), UNSUP(1300),
        UNSUP(1500), UNSUP(1800), 1850, UNSUP(2500),
        2600, 2800, 2850, 3000,
        3150, 3150, 3150, 3150,
};
static const u16 VPLL1_VSEL_table[] = {
        1000, 1200, 1300, 1800,
        UNSUP(2800), UNSUP(3000), UNSUP(3000), UNSUP(3000),
};
static const u16 VPLL2_VSEL_table[] = {
        700, 1000, 1200, 1300,
        UNSUP(1500), 1800, UNSUP(1850), UNSUP(2500),
        UNSUP(2600), UNSUP(2800), UNSUP(2850), UNSUP(3000),
        UNSUP(3150), UNSUP(3150), UNSUP(3150), UNSUP(3150),
};
static const u16 VSIM_VSEL_table[] = {
        UNSUP(1000), UNSUP(1200), UNSUP(1300), 1800,
        2800, 3000, 3000, 3000,
};
static const u16 VDAC_VSEL_table[] = {
        1200, 1300, 1800, 1800,
};
static const u16 VIO_VSEL_table[] = {
        1800, 1850,
};
static const u16 VINTANA2_VSEL_table[] = {
        2500, 2750,
};

static int twl4030ldo_list_voltage(struct regulator_dev *rdev, unsigned index)
{
        struct twlreg_info      *info = rdev_get_drvdata(rdev);
        int                     mV = info->table[index];

        return IS_UNSUP(info, mV) ? 0 : (LDO_MV(mV) * 1000);
}

static int
twl4030ldo_set_voltage_sel(struct regulator_dev *rdev, unsigned selector)
{
        struct twlreg_info      *info = rdev_get_drvdata(rdev);

        return twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE,
                            selector);
}

static int twl4030ldo_get_voltage_sel(struct regulator_dev *rdev)
{
        struct twlreg_info      *info = rdev_get_drvdata(rdev);
        int vsel = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE);

        if (vsel < 0)
                return vsel;

        vsel &= info->table_len - 1;
        return vsel;
}

static struct regulator_ops twl4030ldo_ops = {
        .list_voltage   = twl4030ldo_list_voltage,

        .set_voltage_sel = twl4030ldo_set_voltage_sel,
        .get_voltage_sel = twl4030ldo_get_voltage_sel,

        .enable         = twl4030reg_enable,
        .disable        = twl4030reg_disable,
        .is_enabled     = twl4030reg_is_enabled,

        .set_mode       = twl4030reg_set_mode,

        .get_status     = twl4030reg_get_status,
};

static int
twl4030smps_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
                        unsigned *selector)
{
        struct twlreg_info *info = rdev_get_drvdata(rdev);
        int vsel = DIV_ROUND_UP(min_uV - 600000, 12500);

        twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE_SMPS_4030, vsel);

        return 0;
}

static int twl4030smps_get_voltage(struct regulator_dev *rdev)
{
        struct twlreg_info *info = rdev_get_drvdata(rdev);
        int vsel;

        vsel = twlreg_read(info, TWL_MODULE_PM_RECEIVER,
                VREG_VOLTAGE_SMPS_4030);

        return vsel * 12500 + 600000;
}

static struct regulator_ops twl4030smps_ops = {
        .set_voltage    = twl4030smps_set_voltage,
        .get_voltage    = twl4030smps_get_voltage,
};

/*----------------------------------------------------------------------*/

static struct regulator_ops twl4030fixed_ops = {
        .list_voltage   = regulator_list_voltage_linear,

        .enable         = twl4030reg_enable,
        .disable        = twl4030reg_disable,
        .is_enabled     = twl4030reg_is_enabled,

        .set_mode       = twl4030reg_set_mode,

        .get_status     = twl4030reg_get_status,
};

/*----------------------------------------------------------------------*/

#define TWL4030_ADJUSTABLE_LDO(label, offset, num, turnon_delay, remap_conf) \
static const struct twlreg_info TWL4030_INFO_##label = { \
        .base = offset, \
        .id = num, \
        .table_len = ARRAY_SIZE(label##_VSEL_table), \
        .table = label##_VSEL_table, \
        .remap = remap_conf, \
        .desc = { \
                .name = #label, \
                .id = TWL4030_REG_##label, \
                .n_voltages = ARRAY_SIZE(label##_VSEL_table), \
                .ops = &twl4030ldo_ops, \
                .type = REGULATOR_VOLTAGE, \
                .owner = THIS_MODULE, \
                .enable_time = turnon_delay, \
                .of_map_mode = twl4030reg_map_mode, \
                }, \
        }

#define TWL4030_ADJUSTABLE_SMPS(label, offset, num, turnon_delay, remap_conf) \
static const struct twlreg_info TWL4030_INFO_##label = { \
        .base = offset, \
        .id = num, \
        .remap = remap_conf, \
        .desc = { \
                .name = #label, \
                .id = TWL4030_REG_##label, \
                .ops = &twl4030smps_ops, \
                .type = REGULATOR_VOLTAGE, \
                .owner = THIS_MODULE, \
                .enable_time = turnon_delay, \
                .of_map_mode = twl4030reg_map_mode, \
                }, \
        }

#define TWL4030_FIXED_LDO(label, offset, mVolts, num, turnon_delay, \
                        remap_conf) \
static const struct twlreg_info TWLFIXED_INFO_##label = { \
        .base = offset, \
        .id = num, \
        .remap = remap_conf, \
        .desc = { \
                .name = #label, \
                .id = TWL4030##_REG_##label, \
                .n_voltages = 1, \
                .ops = &twl4030fixed_ops, \
                .type = REGULATOR_VOLTAGE, \
                .owner = THIS_MODULE, \
                .min_uV = mVolts * 1000, \
                .enable_time = turnon_delay, \
                .of_map_mode = twl4030reg_map_mode, \
                }, \
        }

/*
 * We list regulators here if systems need some level of
 * software control over them after boot.
 */
TWL4030_ADJUSTABLE_LDO(VAUX1, 0x17, 1, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VAUX2_4030, 0x1b, 2, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VAUX2, 0x1b, 2, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VAUX3, 0x1f, 3, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VAUX4, 0x23, 4, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VMMC1, 0x27, 5, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VMMC2, 0x2b, 6, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VPLL1, 0x2f, 7, 100, 0x00);
TWL4030_ADJUSTABLE_LDO(VPLL2, 0x33, 8, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VSIM, 0x37, 9, 100, 0x00);
TWL4030_ADJUSTABLE_LDO(VDAC, 0x3b, 10, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VINTANA2, 0x43, 12, 100, 0x08);
TWL4030_ADJUSTABLE_LDO(VIO, 0x4b, 14, 1000, 0x08);
TWL4030_ADJUSTABLE_SMPS(VDD1, 0x55, 15, 1000, 0x08);
TWL4030_ADJUSTABLE_SMPS(VDD2, 0x63, 16, 1000, 0x08);
/* VUSBCP is managed *only* by the USB subchip */
TWL4030_FIXED_LDO(VINTANA1, 0x3f, 1500, 11, 100, 0x08);
TWL4030_FIXED_LDO(VINTDIG, 0x47, 1500, 13, 100, 0x08);
TWL4030_FIXED_LDO(VUSB1V5, 0x71, 1500, 17, 100, 0x08);
TWL4030_FIXED_LDO(VUSB1V8, 0x74, 1800, 18, 100, 0x08);
TWL4030_FIXED_LDO(VUSB3V1, 0x77, 3100, 19, 150, 0x08);

#define TWL_OF_MATCH(comp, family, label) \
        { \
                .compatible = comp, \
                .data = &family##_INFO_##label, \
        }

#define TWL4030_OF_MATCH(comp, label) TWL_OF_MATCH(comp, TWL4030, label)
#define TWL6030_OF_MATCH(comp, label) TWL_OF_MATCH(comp, TWL6030, label)
#define TWL6032_OF_MATCH(comp, label) TWL_OF_MATCH(comp, TWL6032, label)
#define TWLFIXED_OF_MATCH(comp, label) TWL_OF_MATCH(comp, TWLFIXED, label)
#define TWLSMPS_OF_MATCH(comp, label) TWL_OF_MATCH(comp, TWLSMPS, label)

static const struct of_device_id twl_of_match[] = {
        TWL4030_OF_MATCH("ti,twl4030-vaux1", VAUX1),
        TWL4030_OF_MATCH("ti,twl4030-vaux2", VAUX2_4030),
        TWL4030_OF_MATCH("ti,twl5030-vaux2", VAUX2),
        TWL4030_OF_MATCH("ti,twl4030-vaux3", VAUX3),
        TWL4030_OF_MATCH("ti,twl4030-vaux4", VAUX4),
        TWL4030_OF_MATCH("ti,twl4030-vmmc1", VMMC1),
        TWL4030_OF_MATCH("ti,twl4030-vmmc2", VMMC2),
        TWL4030_OF_MATCH("ti,twl4030-vpll1", VPLL1),
        TWL4030_OF_MATCH("ti,twl4030-vpll2", VPLL2),
        TWL4030_OF_MATCH("ti,twl4030-vsim", VSIM),
        TWL4030_OF_MATCH("ti,twl4030-vdac", VDAC),
        TWL4030_OF_MATCH("ti,twl4030-vintana2", VINTANA2),
        TWL4030_OF_MATCH("ti,twl4030-vio", VIO),
        TWL4030_OF_MATCH("ti,twl4030-vdd1", VDD1),
        TWL4030_OF_MATCH("ti,twl4030-vdd2", VDD2),
        TWLFIXED_OF_MATCH("ti,twl4030-vintana1", VINTANA1),
        TWLFIXED_OF_MATCH("ti,twl4030-vintdig", VINTDIG),
        TWLFIXED_OF_MATCH("ti,twl4030-vusb1v5", VUSB1V5),
        TWLFIXED_OF_MATCH("ti,twl4030-vusb1v8", VUSB1V8),
        TWLFIXED_OF_MATCH("ti,twl4030-vusb3v1", VUSB3V1),
        {},
};
MODULE_DEVICE_TABLE(of, twl_of_match);

static int twlreg_probe(struct platform_device *pdev)
{
        int id;
        struct twlreg_info              *info;
        const struct twlreg_info        *template;
        struct regulator_init_data      *initdata;
        struct regulation_constraints   *c;
        struct regulator_dev            *rdev;
        const struct of_device_id       *match;
        struct regulator_config         config = { };

        match = of_match_device(twl_of_match, &pdev->dev);
        if (!match)
                return -ENODEV;

        template = match->data;
        if (!template)
                return -ENODEV;

        id = template->desc.id;
        initdata = of_get_regulator_init_data(&pdev->dev, pdev->dev.of_node,
                                                &template->desc);
        if (!initdata)
                return -EINVAL;

        info = devm_kmemdup(&pdev->dev, template, sizeof(*info), GFP_KERNEL);
        if (!info)
                return -ENOMEM;

        /* Constrain board-specific capabilities according to what
         * this driver and the chip itself can actually do.
         */
        c = &initdata->constraints;
        c->valid_modes_mask &= REGULATOR_MODE_NORMAL | REGULATOR_MODE_STANDBY;
        c->valid_ops_mask &= REGULATOR_CHANGE_VOLTAGE
                                | REGULATOR_CHANGE_MODE
                                | REGULATOR_CHANGE_STATUS;
        switch (id) {
        case TWL4030_REG_VIO:
        case TWL4030_REG_VDD1:
        case TWL4030_REG_VDD2:
        case TWL4030_REG_VPLL1:
        case TWL4030_REG_VINTANA1:
        case TWL4030_REG_VINTANA2:
        case TWL4030_REG_VINTDIG:
                c->always_on = true;
                break;
        default:
                break;
        }

        config.dev = &pdev->dev;
        config.init_data = initdata;
        config.driver_data = info;
        config.of_node = pdev->dev.of_node;

        rdev = devm_regulator_register(&pdev->dev, &info->desc, &config);
        if (IS_ERR(rdev)) {
                dev_err(&pdev->dev, "can't register %s, %ld\n",
                                info->desc.name, PTR_ERR(rdev));
                return PTR_ERR(rdev);
        }
        platform_set_drvdata(pdev, rdev);

        twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_REMAP, info->remap);

        /* NOTE:  many regulators support short-circuit IRQs (presentable
         * as REGULATOR_OVER_CURRENT notifications?) configured via:
         *  - SC_CONFIG
         *  - SC_DETECT1 (vintana2, vmmc1/2, vaux1/2/3/4)
         *  - SC_DETECT2 (vusb, vdac, vio, vdd1/2, vpll2)
         *  - IT_CONFIG
         */

        return 0;
}

MODULE_ALIAS("platform:twl4030_reg");

static struct platform_driver twlreg_driver = {
        .probe          = twlreg_probe,
        /* NOTE: short name, to work around driver model truncation of
         * "twl_regulator.12" (and friends) to "twl_regulator.1".
         */
        .driver  = {
                .name  = "twl4030_reg",
                .of_match_table = of_match_ptr(twl_of_match),
        },
};

static int __init twlreg_init(void)
{
        return platform_driver_register(&twlreg_driver);
}
subsys_initcall(twlreg_init);

static void __exit twlreg_exit(void)
{
        platform_driver_unregister(&twlreg_driver);
}
module_exit(twlreg_exit)

MODULE_DESCRIPTION("TWL4030 regulator driver");
MODULE_LICENSE("GPL");