regulator: add driver for tps6524x regulator

TPS6524X provides three step-down converters and two general-purpose LDO
voltage regulators.  This device is interfaced using SPI.

Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

1 files changed, 693 insertions, 0 deletions

diff --git a/drivers/regulator/tps6524x-regulator.c b/drivers/regulator/tps6524x-regulator.c
new file mode 100644
index 000000000000..176a6be5a8ce
--- /dev/null
+++ b/drivers/regulator/tps6524x-regulator.c
@@ -0,0 +1,693 @@
+/*
+ * Regulator driver for TPS6524x PMIC
+ *
+ * Copyright (C) 2010 Texas Instruments
+ *
+ * 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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
+ * whether express or implied; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+
+#define REG_LDO_SET             0x0
+#define LDO_ILIM_MASK           1       /* 0 = 400-800, 1 = 900-1500 */
+#define LDO_VSEL_MASK           0x0f
+#define LDO2_ILIM_SHIFT         12
+#define LDO2_VSEL_SHIFT         4
+#define LDO1_ILIM_SHIFT         8
+#define LDO1_VSEL_SHIFT         0
+
+#define REG_BLOCK_EN            0x1
+#define BLOCK_MASK              1
+#define BLOCK_LDO1_SHIFT        0
+#define BLOCK_LDO2_SHIFT        1
+#define BLOCK_LCD_SHIFT         2
+#define BLOCK_USB_SHIFT         3
+
+#define REG_DCDC_SET            0x2
+#define DCDC_VDCDC_MASK         0x1f
+#define DCDC_VDCDC1_SHIFT       0
+#define DCDC_VDCDC2_SHIFT       5
+#define DCDC_VDCDC3_SHIFT       10
+
+#define REG_DCDC_EN             0x3
+#define DCDCDCDC_EN_MASK        0x1
+#define DCDCDCDC1_EN_SHIFT      0
+#define DCDCDCDC1_PG_MSK        BIT(1)
+#define DCDCDCDC2_EN_SHIFT      2
+#define DCDCDCDC2_PG_MSK        BIT(3)
+#define DCDCDCDC3_EN_SHIFT      4
+#define DCDCDCDC3_PG_MSK        BIT(5)
+
+#define REG_USB                 0x4
+#define USB_ILIM_SHIFT          0
+#define USB_ILIM_MASK           0x3
+#define USB_TSD_SHIFT           2
+#define USB_TSD_MASK            0x3
+#define USB_TWARN_SHIFT         4
+#define USB_TWARN_MASK          0x3
+#define USB_IWARN_SD            BIT(6)
+#define USB_FAST_LOOP           BIT(7)
+
+#define REG_ALARM               0x5
+#define ALARM_LDO1              BIT(0)
+#define ALARM_DCDC1             BIT(1)
+#define ALARM_DCDC2             BIT(2)
+#define ALARM_DCDC3             BIT(3)
+#define ALARM_LDO2              BIT(4)
+#define ALARM_USB_WARN          BIT(5)
+#define ALARM_USB_ALARM         BIT(6)
+#define ALARM_LCD               BIT(9)
+#define ALARM_TEMP_WARM         BIT(10)
+#define ALARM_TEMP_HOT          BIT(11)
+#define ALARM_NRST              BIT(14)
+#define ALARM_POWERUP           BIT(15)
+
+#define REG_INT_ENABLE          0x6
+#define INT_LDO1                BIT(0)
+#define INT_DCDC1               BIT(1)
+#define INT_DCDC2               BIT(2)
+#define INT_DCDC3               BIT(3)
+#define INT_LDO2                BIT(4)
+#define INT_USB_WARN            BIT(5)
+#define INT_USB_ALARM           BIT(6)
+#define INT_LCD                 BIT(9)
+#define INT_TEMP_WARM           BIT(10)
+#define INT_TEMP_HOT            BIT(11)
+#define INT_GLOBAL_EN           BIT(15)
+
+#define REG_INT_STATUS          0x7
+#define STATUS_LDO1             BIT(0)
+#define STATUS_DCDC1            BIT(1)
+#define STATUS_DCDC2            BIT(2)
+#define STATUS_DCDC3            BIT(3)
+#define STATUS_LDO2             BIT(4)
+#define STATUS_USB_WARN         BIT(5)
+#define STATUS_USB_ALARM        BIT(6)
+#define STATUS_LCD              BIT(9)
+#define STATUS_TEMP_WARM        BIT(10)
+#define STATUS_TEMP_HOT         BIT(11)
+
+#define REG_SOFTWARE_RESET      0xb
+#define REG_WRITE_ENABLE        0xd
+#define REG_REV_ID              0xf
+
+#define N_DCDC                  3
+#define N_LDO                   2
+#define N_SWITCH                2
+#define N_REGULATORS            (3 /* DCDC */ + \
+                                 2 /* LDO */  + \
+                                 2 /* switch */)
+
+#define FIXED_ILIMSEL           BIT(0)
+#define FIXED_VOLTAGE           BIT(1)
+
+#define CMD_READ(reg)           ((reg) << 6)
+#define CMD_WRITE(reg)          (BIT(5) | (reg) << 6)
+#define STAT_CLK                BIT(3)
+#define STAT_WRITE              BIT(2)
+#define STAT_INVALID            BIT(1)
+#define STAT_WP                 BIT(0)
+
+struct field {
+        int             reg;
+        int             shift;
+        int             mask;
+};
+
+struct supply_info {
+        const char      *name;
+        int             n_voltages;
+        const int       *voltages;
+        int             fixed_voltage;
+        int             n_ilimsels;
+        const int       *ilimsels;
+        int             fixed_ilimsel;
+        int             flags;
+        struct field    enable, voltage, ilimsel;
+};
+
+struct tps6524x {
+        struct device           *dev;
+        struct spi_device       *spi;
+        struct mutex            lock;
+        struct regulator_desc   desc[N_REGULATORS];
+        struct regulator_dev    *rdev[N_REGULATORS];
+};
+
+static int __read_reg(struct tps6524x *hw, int reg)
+{
+        int error = 0;
+        u16 cmd = CMD_READ(reg), in;
+        u8 status;
+        struct spi_message m;
+        struct spi_transfer t[3];
+
+        spi_message_init(&m);
+        memset(t, 0, sizeof(t));
+
+        t[0].tx_buf = &cmd;
+        t[0].len = 2;
+        t[0].bits_per_word = 12;
+        spi_message_add_tail(&t[0], &m);
+
+        t[1].rx_buf = &in;
+        t[1].len = 2;
+        t[1].bits_per_word = 16;
+        spi_message_add_tail(&t[1], &m);
+
+        t[2].rx_buf = &status;
+        t[2].len = 1;
+        t[2].bits_per_word = 4;
+        spi_message_add_tail(&t[2], &m);
+
+        error = spi_sync(hw->spi, &m);
+        if (error < 0)
+                return error;
+
+        dev_dbg(hw->dev, "read reg %d, data %x, status %x\n",
+                reg, in, status);
+
+        if (!(status & STAT_CLK) || (status & STAT_WRITE))
+                return -EIO;
+
+        if (status & STAT_INVALID)
+                return -EINVAL;
+
+        return in;
+}
+
+static int read_reg(struct tps6524x *hw, int reg)
+{
+        int ret;
+
+        mutex_lock(&hw->lock);
+        ret = __read_reg(hw, reg);
+        mutex_unlock(&hw->lock);
+
+        return ret;
+}
+
+static int __write_reg(struct tps6524x *hw, int reg, int val)
+{
+        int error = 0;
+        u16 cmd = CMD_WRITE(reg), out = val;
+        u8 status;
+        struct spi_message m;
+        struct spi_transfer t[3];
+
+        spi_message_init(&m);
+        memset(t, 0, sizeof(t));
+
+        t[0].tx_buf = &cmd;
+        t[0].len = 2;
+        t[0].bits_per_word = 12;
+        spi_message_add_tail(&t[0], &m);
+
+        t[1].tx_buf = &out;
+        t[1].len = 2;
+        t[1].bits_per_word = 16;
+        spi_message_add_tail(&t[1], &m);
+
+        t[2].rx_buf = &status;
+        t[2].len = 1;
+        t[2].bits_per_word = 4;
+        spi_message_add_tail(&t[2], &m);
+
+        error = spi_sync(hw->spi, &m);
+        if (error < 0)
+                return error;
+
+        dev_dbg(hw->dev, "wrote reg %d, data %x, status %x\n",
+                reg, out, status);
+
+        if (!(status & STAT_CLK) || !(status & STAT_WRITE))
+                return -EIO;
+
+        if (status & (STAT_INVALID | STAT_WP))
+                return -EINVAL;
+
+        return error;
+}
+
+static int __rmw_reg(struct tps6524x *hw, int reg, int mask, int val)
+{
+        int ret;
+
+        ret = __read_reg(hw, reg);
+        if (ret < 0)
+                return ret;
+
+        ret &= ~mask;
+        ret |= val;
+
+        ret = __write_reg(hw, reg, ret);
+
+        return (ret < 0) ? ret : 0;
+}
+
+static int rmw_protect(struct tps6524x *hw, int reg, int mask, int val)
+{
+        int ret;
+
+        mutex_lock(&hw->lock);
+
+        ret = __write_reg(hw, REG_WRITE_ENABLE, 1);
+        if (ret) {
+                dev_err(hw->dev, "failed to set write enable\n");
+                goto error;
+        }
+
+        ret = __rmw_reg(hw, reg, mask, val);
+        if (ret)
+                dev_err(hw->dev, "failed to rmw register %d\n", reg);
+
+        ret = __write_reg(hw, REG_WRITE_ENABLE, 0);
+        if (ret) {
+                dev_err(hw->dev, "failed to clear write enable\n");
+                goto error;
+        }
+
+error:
+        mutex_unlock(&hw->lock);
+
+        return ret;
+}
+
+static int read_field(struct tps6524x *hw, const struct field *field)
+{
+        int tmp;
+
+        tmp = read_reg(hw, field->reg);
+        if (tmp < 0)
+                return tmp;
+
+        return (tmp >> field->shift) & field->mask;
+}
+
+static int write_field(struct tps6524x *hw, const struct field *field,
+                       int val)
+{
+        if (val & ~field->mask)
+                return -EOVERFLOW;
+
+        return rmw_protect(hw, field->reg,
+                                    field->mask << field->shift,
+                                    val << field->shift);
+}
+
+static const int dcdc1_voltages[] = {
+         800000,  825000,  850000,  875000,
+         900000,  925000,  950000,  975000,
+        1000000, 1025000, 1050000, 1075000,
+        1100000, 1125000, 1150000, 1175000,
+        1200000, 1225000, 1250000, 1275000,
+        1300000, 1325000, 1350000, 1375000,
+        1400000, 1425000, 1450000, 1475000,
+        1500000, 1525000, 1550000, 1575000,
+};
+
+static const int dcdc2_voltages[] = {
+        1400000, 1450000, 1500000, 1550000,
+        1600000, 1650000, 1700000, 1750000,
+        1800000, 1850000, 1900000, 1950000,
+        2000000, 2050000, 2100000, 2150000,
+        2200000, 2250000, 2300000, 2350000,
+        2400000, 2450000, 2500000, 2550000,
+        2600000, 2650000, 2700000, 2750000,
+        2800000, 2850000, 2900000, 2950000,
+};
+
+static const int dcdc3_voltages[] = {
+        2400000, 2450000, 2500000, 2550000, 2600000,
+        2650000, 2700000, 2750000, 2800000, 2850000,
+        2900000, 2950000, 3000000, 3050000, 3100000,
+        3150000, 3200000, 3250000, 3300000, 3350000,
+        3400000, 3450000, 3500000, 3550000, 3600000,
+};
+
+static const int ldo1_voltages[] = {
+        4300000, 4350000, 4400000, 4450000,
+        4500000, 4550000, 4600000, 4650000,
+        4700000, 4750000, 4800000, 4850000,
+        4900000, 4950000, 5000000, 5050000,
+};
+
+static const int ldo2_voltages[] = {
+        1100000, 1150000, 1200000, 1250000,
+        1300000, 1700000, 1750000, 1800000,
+        1850000, 1900000, 3150000, 3200000,
+        3250000, 3300000, 3350000, 3400000,
+};
+
+static const int ldo_ilimsel[] = {
+        400000, 1500000
+};
+
+static const int usb_ilimsel[] = {
+        200000, 400000, 800000, 1000000
+};
+
+#define __MK_FIELD(_reg, _mask, _shift) \
+        { .reg = (_reg), .mask = (_mask), .shift = (_shift), }
+
+static const struct supply_info supply_info[N_REGULATORS] = {
+        {
+                .name           = "DCDC1",
+                .flags          = FIXED_ILIMSEL,
+                .n_voltages     = ARRAY_SIZE(dcdc1_voltages),
+                .voltages       = dcdc1_voltages,
+                .fixed_ilimsel  = 2400000,
+                .enable         = __MK_FIELD(REG_DCDC_EN, DCDCDCDC_EN_MASK,
+                                             DCDCDCDC1_EN_SHIFT),
+                .voltage        = __MK_FIELD(REG_DCDC_SET, DCDC_VDCDC_MASK,
+                                             DCDC_VDCDC1_SHIFT),
+        },
+        {
+                .name           = "DCDC2",
+                .flags          = FIXED_ILIMSEL,
+                .n_voltages     = ARRAY_SIZE(dcdc2_voltages),
+                .voltages       = dcdc2_voltages,
+                .fixed_ilimsel  = 1200000,
+                .enable         = __MK_FIELD(REG_DCDC_EN, DCDCDCDC_EN_MASK,
+                                             DCDCDCDC2_EN_SHIFT),
+                .voltage        = __MK_FIELD(REG_DCDC_SET, DCDC_VDCDC_MASK,
+                                             DCDC_VDCDC2_SHIFT),
+        },
+        {
+                .name           = "DCDC3",
+                .flags          = FIXED_ILIMSEL,
+                .n_voltages     = ARRAY_SIZE(dcdc3_voltages),
+                .voltages       = dcdc3_voltages,
+                .fixed_ilimsel  = 1200000,
+                .enable         = __MK_FIELD(REG_DCDC_EN, DCDCDCDC_EN_MASK,
+                                        DCDCDCDC3_EN_SHIFT),
+                .voltage        = __MK_FIELD(REG_DCDC_SET, DCDC_VDCDC_MASK,
+                                             DCDC_VDCDC3_SHIFT),
+        },
+        {
+                .name           = "LDO1",
+                .n_voltages     = ARRAY_SIZE(ldo1_voltages),
+                .voltages       = ldo1_voltages,
+                .n_ilimsels     = ARRAY_SIZE(ldo_ilimsel),
+                .ilimsels       = ldo_ilimsel,
+                .enable         = __MK_FIELD(REG_BLOCK_EN, BLOCK_MASK,
+                                             BLOCK_LDO1_SHIFT),
+                .voltage        = __MK_FIELD(REG_LDO_SET, LDO_VSEL_MASK,
+                                             LDO1_VSEL_SHIFT),
+                .ilimsel        = __MK_FIELD(REG_LDO_SET, LDO_ILIM_MASK,
+                                             LDO1_ILIM_SHIFT),
+        },
+        {
+                .name           = "LDO2",
+                .n_voltages     = ARRAY_SIZE(ldo2_voltages),
+                .voltages       = ldo2_voltages,
+                .n_ilimsels     = ARRAY_SIZE(ldo_ilimsel),
+                .ilimsels       = ldo_ilimsel,
+                .enable         = __MK_FIELD(REG_BLOCK_EN, BLOCK_MASK,
+                                             BLOCK_LDO2_SHIFT),
+                .voltage        = __MK_FIELD(REG_LDO_SET, LDO_VSEL_MASK,
+                                             LDO2_VSEL_SHIFT),
+                .ilimsel        = __MK_FIELD(REG_LDO_SET, LDO_ILIM_MASK,
+                                             LDO2_ILIM_SHIFT),
+        },
+        {
+                .name           = "USB",
+                .flags          = FIXED_VOLTAGE,
+                .fixed_voltage  = 5000000,
+                .n_ilimsels     = ARRAY_SIZE(usb_ilimsel),
+                .ilimsels       = usb_ilimsel,
+                .enable         = __MK_FIELD(REG_BLOCK_EN, BLOCK_MASK,
+                                             BLOCK_USB_SHIFT),
+                .ilimsel        = __MK_FIELD(REG_USB, USB_ILIM_MASK,
+                                             USB_ILIM_SHIFT),
+        },
+        {
+                .name           = "LCD",
+                .flags          = FIXED_VOLTAGE | FIXED_ILIMSEL,
+                .fixed_voltage  = 5000000,
+                .fixed_ilimsel  =  400000,
+                .enable         = __MK_FIELD(REG_BLOCK_EN, BLOCK_MASK,
+                                             BLOCK_LCD_SHIFT),
+        },
+};
+
+static int list_voltage(struct regulator_dev *rdev, unsigned selector)
+{
+        const struct supply_info *info;
+        struct tps6524x *hw;
+
+        hw      = rdev_get_drvdata(rdev);
+        info    = &supply_info[rdev_get_id(rdev)];
+
+        if (info->flags & FIXED_VOLTAGE)
+                return selector ? -EINVAL : info->fixed_voltage;
+
+        return ((selector < info->n_voltages) ?
+                info->voltages[selector] : -EINVAL);
+}
+
+static int set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
+                       unsigned *selector)
+{
+        const struct supply_info *info;
+        struct tps6524x *hw;
+        unsigned i;
+
+        hw      = rdev_get_drvdata(rdev);
+        info    = &supply_info[rdev_get_id(rdev)];
+
+        if (info->flags & FIXED_VOLTAGE)
+                return -EINVAL;
+
+        for (i = 0; i < info->n_voltages; i++)
+                if (min_uV <= info->voltages[i] &&
+                    max_uV >= info->voltages[i])
+                        break;
+
+        if (i >= info->n_voltages)
+                i = info->n_voltages - 1;
+
+        *selector = info->voltages[i];
+
+        return write_field(hw, &info->voltage, i);
+}
+
+static int get_voltage(struct regulator_dev *rdev)
+{
+        const struct supply_info *info;
+        struct tps6524x *hw;
+        int ret;
+
+        hw      = rdev_get_drvdata(rdev);
+        info    = &supply_info[rdev_get_id(rdev)];
+
+        if (info->flags & FIXED_VOLTAGE)
+                return info->fixed_voltage;
+
+        ret = read_field(hw, &info->voltage);
+        if (ret < 0)
+                return ret;
+        if (WARN_ON(ret >= info->n_voltages))
+                return -EIO;
+
+        return info->voltages[ret];
+}
+
+static int set_current_limit(struct regulator_dev *rdev, int min_uA,
+                             int max_uA)
+{
+        const struct supply_info *info;
+        struct tps6524x *hw;
+        int i;
+
+        hw      = rdev_get_drvdata(rdev);
+        info    = &supply_info[rdev_get_id(rdev)];
+
+        if (info->flags & FIXED_ILIMSEL)
+                return -EINVAL;
+
+        for (i = 0; i < info->n_ilimsels; i++)
+                if (min_uA <= info->ilimsels[i] &&
+                    max_uA >= info->ilimsels[i])
+                        break;
+
+        if (i >= info->n_ilimsels)
+                return -EINVAL;
+
+        return write_field(hw, &info->ilimsel, i);
+}
+
+static int get_current_limit(struct regulator_dev *rdev)
+{
+        const struct supply_info *info;
+        struct tps6524x *hw;
+        int ret;
+
+        hw      = rdev_get_drvdata(rdev);
+        info    = &supply_info[rdev_get_id(rdev)];
+
+        if (info->flags & FIXED_ILIMSEL)
+                return info->fixed_ilimsel;
+
+        ret = read_field(hw, &info->ilimsel);
+        if (ret < 0)
+                return ret;
+        if (WARN_ON(ret >= info->n_ilimsels))
+                return -EIO;
+
+        return info->ilimsels[ret];
+}
+
+static int enable_supply(struct regulator_dev *rdev)
+{
+        const struct supply_info *info;
+        struct tps6524x *hw;
+
+        hw      = rdev_get_drvdata(rdev);
+        info    = &supply_info[rdev_get_id(rdev)];
+
+        return write_field(hw, &info->enable, 1);
+}
+
+static int disable_supply(struct regulator_dev *rdev)
+{
+        const struct supply_info *info;
+        struct tps6524x *hw;
+
+        hw      = rdev_get_drvdata(rdev);
+        info    = &supply_info[rdev_get_id(rdev)];
+
+        return write_field(hw, &info->enable, 0);
+}
+
+static int is_supply_enabled(struct regulator_dev *rdev)
+{
+        const struct supply_info *info;
+        struct tps6524x *hw;
+
+        hw      = rdev_get_drvdata(rdev);
+        info    = &supply_info[rdev_get_id(rdev)];
+
+        return read_field(hw, &info->enable);
+}
+
+static struct regulator_ops regulator_ops = {
+        .is_enabled             = is_supply_enabled,
+        .enable                 = enable_supply,
+        .disable                = disable_supply,
+        .get_voltage            = get_voltage,
+        .set_voltage            = set_voltage,
+        .list_voltage           = list_voltage,
+        .set_current_limit      = set_current_limit,
+        .get_current_limit      = get_current_limit,
+};
+
+static int __devexit pmic_remove(struct spi_device *spi)
+{
+        struct tps6524x *hw = spi_get_drvdata(spi);
+        int i;
+
+        if (!hw)
+                return 0;
+        for (i = 0; i < N_REGULATORS; i++) {
+                if (hw->rdev[i])
+                        regulator_unregister(hw->rdev[i]);
+                hw->rdev[i] = NULL;
+        }
+        spi_set_drvdata(spi, NULL);
+        kfree(hw);
+        return 0;
+}
+
+static int __devinit pmic_probe(struct spi_device *spi)
+{
+        struct tps6524x *hw;
+        struct device *dev = &spi->dev;
+        const struct supply_info *info = supply_info;
+        struct regulator_init_data *init_data;
+        int ret = 0, i;
+
+        init_data = dev->platform_data;
+        if (!init_data) {
+                dev_err(dev, "could not find regulator platform data\n");
+                return -EINVAL;
+        }
+
+        hw = kzalloc(sizeof(struct tps6524x), GFP_KERNEL);
+        if (!hw) {
+                dev_err(dev, "cannot allocate regulator private data\n");
+                return -ENOMEM;
+        }
+        spi_set_drvdata(spi, hw);
+
+        memset(hw, 0, sizeof(struct tps6524x));
+        hw->dev = dev;
+        hw->spi = spi_dev_get(spi);
+        mutex_init(&hw->lock);
+
+        for (i = 0; i < N_REGULATORS; i++, info++, init_data++) {
+                hw->desc[i].name        = info->name;
+                hw->desc[i].id          = i;
+                hw->desc[i].n_voltages  = info->n_voltages;
+                hw->desc[i].ops         = &regulator_ops;
+                hw->desc[i].type        = REGULATOR_VOLTAGE;
+                hw->desc[i].owner       = THIS_MODULE;
+
+                if (info->flags & FIXED_VOLTAGE)
+                        hw->desc[i].n_voltages = 1;
+
+                hw->rdev[i] = regulator_register(&hw->desc[i], dev,
+                                                 init_data, hw);
+                if (IS_ERR(hw->rdev[i])) {
+                        ret = PTR_ERR(hw->rdev[i]);
+                        hw->rdev[i] = NULL;
+                        goto fail;
+                }
+        }
+
+        return 0;
+
+fail:
+        pmic_remove(spi);
+        return ret;
+}
+
+static struct spi_driver pmic_driver = {
+        .probe          = pmic_probe,
+        .remove         = __devexit_p(pmic_remove),
+        .driver         = {
+                .name   = "tps6524x",
+                .owner  = THIS_MODULE,
+        },
+};
+
+static int __init pmic_driver_init(void)
+{
+        return spi_register_driver(&pmic_driver);
+}
+module_init(pmic_driver_init);
+
+static void __exit pmic_driver_exit(void)
+{
+        spi_unregister_driver(&pmic_driver);
+}
+module_exit(pmic_driver_exit);
+
+MODULE_DESCRIPTION("TPS6524X PMIC Driver");
+MODULE_AUTHOR("Cyril Chemparathy");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:tps6524x");