regulator: AB3100 support

This adds support for the regulators found in the AB3100
Mixed-Signal IC.

It further also defines platform data for the ST-Ericsson
U300 platform and extends the AB3100 MFD driver so that
platform/board data with regulation constraints and an init
function can be passed down all the way from the board to
the regulators.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

5 files changed, 736 insertions, 0 deletions

diff --git a/drivers/mfd/ab3100-core.c b/drivers/mfd/ab3100-core.c
index a848df77514a..c533f86ff5ea 100644
--- a/drivers/mfd/ab3100-core.c
+++ b/drivers/mfd/ab3100-core.c
@@ -837,6 +837,8 @@ static int __init ab3100_probe(struct i2c_client *client,
                         const struct i2c_device_id *id)
 {
         struct ab3100 *ab3100;
+        struct ab3100_platform_data *ab3100_plf_data =
+                client->dev.platform_data;
         int err;
         int i;
 
@@ -920,6 +922,8 @@ static int __init ab3100_probe(struct i2c_client *client,
         for (i = 0; i < ARRAY_SIZE(ab3100_platform_devs); i++) {
                 ab3100_platform_devs[i]->dev.parent =
                         &client->dev;
+                ab3100_platform_devs[i]->dev.platform_data =
+                        ab3100_plf_data;
                 platform_set_drvdata(ab3100_platform_devs[i], ab3100);
         }
 
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index c505714b0a98..2dc42bbf6fe9 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -138,5 +138,14 @@ config REGULATOR_MC13783
           Say y here to support the regulators found on the Freescale MC13783
           PMIC.
 
+config REGULATOR_AB3100
+        tristate "ST-Ericsson AB3100 Regulator functions"
+        depends on AB3100_CORE
+        default y if AB3100_CORE
+        help
+         These regulators correspond to functionality in the
+         AB3100 analog baseband dealing with power regulators
+         for the system.
+
 endif
 
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 5034830a395e..768b3316d6eb 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -21,5 +21,6 @@ obj-$(CONFIG_REGULATOR_DA903X)	+= da903x.o
 obj-$(CONFIG_REGULATOR_PCF50633) += pcf50633-regulator.o
 obj-$(CONFIG_REGULATOR_PCAP) += pcap-regulator.o
 obj-$(CONFIG_REGULATOR_MC13783) += mc13783.o
+obj-$(CONFIG_REGULATOR_AB3100) += ab3100.o
 
 ccflags-$(CONFIG_REGULATOR_DEBUG) += -DDEBUG
diff --git a/drivers/regulator/ab3100.c b/drivers/regulator/ab3100.c
new file mode 100644
index 000000000000..156979d1f41e
--- /dev/null
+++ b/drivers/regulator/ab3100.c
@@ -0,0 +1,694 @@
+/*
+ * drivers/regulator/ab3100.c
+ *
+ * Copyright (C) 2008-2009 ST-Ericsson AB
+ * License terms: GNU General Public License (GPL) version 2
+ * Low-level control of the AB3100 IC Low Dropout (LDO)
+ * regulators, external regulator and buck converter
+ * Author: Mattias Wallin <mattias.wallin@stericsson.com>
+ * Author: Linus Walleij <linus.walleij@stericsson.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/mfd/ab3100.h>
+
+/* LDO registers and some handy masking definitions for AB3100 */
+#define AB3100_LDO_A            0x40
+#define AB3100_LDO_C            0x41
+#define AB3100_LDO_D            0x42
+#define AB3100_LDO_E            0x43
+#define AB3100_LDO_E_SLEEP      0x44
+#define AB3100_LDO_F            0x45
+#define AB3100_LDO_G            0x46
+#define AB3100_LDO_H            0x47
+#define AB3100_LDO_H_SLEEP_MODE 0
+#define AB3100_LDO_H_SLEEP_EN   2
+#define AB3100_LDO_ON           4
+#define AB3100_LDO_H_VSEL_AC    5
+#define AB3100_LDO_K            0x48
+#define AB3100_LDO_EXT          0x49
+#define AB3100_BUCK             0x4A
+#define AB3100_BUCK_SLEEP       0x4B
+#define AB3100_REG_ON_MASK      0x10
+
+/**
+ * struct ab3100_regulator
+ * A struct passed around the individual regulator functions
+ * @platform_device: platform device holding this regulator
+ * @ab3100: handle to the AB3100 parent chip
+ * @plfdata: AB3100 platform data passed in at probe time
+ * @regreg: regulator register number in the AB3100
+ * @fixed_voltage: a fixed voltage for this regulator, if this
+ *          0 the voltages array is used instead.
+ * @typ_voltages: an array of available typical voltages for
+ *          this regulator
+ * @voltages_len: length of the array of available voltages
+ */
+struct ab3100_regulator {
+        struct regulator_dev *rdev;
+        struct ab3100 *ab3100;
+        struct ab3100_platform_data *plfdata;
+        u8 regreg;
+        int fixed_voltage;
+        int const *typ_voltages;
+        u8 voltages_len;
+};
+
+/* The order in which registers are initialized */
+static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = {
+        AB3100_LDO_A,
+        AB3100_LDO_C,
+        AB3100_LDO_E,
+        AB3100_LDO_E_SLEEP,
+        AB3100_LDO_F,
+        AB3100_LDO_G,
+        AB3100_LDO_H,
+        AB3100_LDO_K,
+        AB3100_LDO_EXT,
+        AB3100_BUCK,
+        AB3100_BUCK_SLEEP,
+        AB3100_LDO_D,
+};
+
+/* Preset (hardware defined) voltages for these regulators */
+#define LDO_A_VOLTAGE 2750000
+#define LDO_C_VOLTAGE 2650000
+#define LDO_D_VOLTAGE 2650000
+
+static const int const ldo_e_buck_typ_voltages[] = {
+        1800000,
+        1400000,
+        1300000,
+        1200000,
+        1100000,
+        1050000,
+        900000,
+};
+
+static const int const ldo_f_typ_voltages[] = {
+        1800000,
+        1400000,
+        1300000,
+        1200000,
+        1100000,
+        1050000,
+        2500000,
+        2650000,
+};
+
+static const int const ldo_g_typ_voltages[] = {
+        2850000,
+        2750000,
+        1800000,
+        1500000,
+};
+
+static const int const ldo_h_typ_voltages[] = {
+        2750000,
+        1800000,
+        1500000,
+        1200000,
+};
+
+static const int const ldo_k_typ_voltages[] = {
+        2750000,
+        1800000,
+};
+
+
+/* The regulator devices */
+static struct ab3100_regulator
+ab3100_regulators[AB3100_NUM_REGULATORS] = {
+        {
+                .regreg = AB3100_LDO_A,
+                .fixed_voltage = LDO_A_VOLTAGE,
+        },
+        {
+                .regreg = AB3100_LDO_C,
+                .fixed_voltage = LDO_C_VOLTAGE,
+        },
+        {
+                .regreg = AB3100_LDO_D,
+                .fixed_voltage = LDO_D_VOLTAGE,
+        },
+        {
+                .regreg = AB3100_LDO_E,
+                .typ_voltages = ldo_e_buck_typ_voltages,
+                .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
+        },
+        {
+                .regreg = AB3100_LDO_F,
+                .typ_voltages = ldo_f_typ_voltages,
+                .voltages_len = ARRAY_SIZE(ldo_f_typ_voltages),
+        },
+        {
+                .regreg = AB3100_LDO_G,
+                .typ_voltages = ldo_g_typ_voltages,
+                .voltages_len = ARRAY_SIZE(ldo_g_typ_voltages),
+        },
+        {
+                .regreg = AB3100_LDO_H,
+                .typ_voltages = ldo_h_typ_voltages,
+                .voltages_len = ARRAY_SIZE(ldo_h_typ_voltages),
+        },
+        {
+                .regreg = AB3100_LDO_K,
+                .typ_voltages = ldo_k_typ_voltages,
+                .voltages_len = ARRAY_SIZE(ldo_k_typ_voltages),
+        },
+        {
+                .regreg = AB3100_LDO_EXT,
+                /* No voltages for the external regulator */
+        },
+        {
+                .regreg = AB3100_BUCK,
+                .typ_voltages = ldo_e_buck_typ_voltages,
+                .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
+        },
+};
+
+/*
+ * General functions for enable, disable and is_enabled used for
+ * LDO: A,C,E,F,G,H,K,EXT and BUCK
+ */
+static int ab3100_enable_regulator(struct regulator_dev *reg)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+        int err;
+        u8 regval;
+
+        err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
+                                                &regval);
+        if (err) {
+                dev_warn(&reg->dev, "failed to get regid %d value\n",
+                         abreg->regreg);
+                return err;
+        }
+
+        /* The regulator is already on, no reason to go further */
+        if (regval & AB3100_REG_ON_MASK)
+                return 0;
+
+        regval |= AB3100_REG_ON_MASK;
+
+        err = ab3100_set_register_interruptible(abreg->ab3100, abreg->regreg,
+                                                regval);
+        if (err) {
+                dev_warn(&reg->dev, "failed to set regid %d value\n",
+                         abreg->regreg);
+                return err;
+        }
+
+        /* Per-regulator power on delay from spec */
+        switch (abreg->regreg) {
+        case AB3100_LDO_A: /* Fallthrough */
+        case AB3100_LDO_C: /* Fallthrough */
+        case AB3100_LDO_D: /* Fallthrough */
+        case AB3100_LDO_E: /* Fallthrough */
+        case AB3100_LDO_H: /* Fallthrough */
+        case AB3100_LDO_K:
+                udelay(200);
+                break;
+        case AB3100_LDO_F:
+                udelay(600);
+                break;
+        case AB3100_LDO_G:
+                udelay(400);
+                break;
+        case AB3100_BUCK:
+                mdelay(1);
+                break;
+        default:
+                break;
+        }
+
+        return 0;
+}
+
+static int ab3100_disable_regulator(struct regulator_dev *reg)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+        int err;
+        u8 regval;
+
+        /*
+         * LDO D is a special regulator. When it is disabled, the entire
+         * system is shut down. So this is handled specially.
+         */
+        if (abreg->regreg == AB3100_LDO_D) {
+                int i;
+
+                dev_info(&reg->dev, "disabling LDO D - shut down system\n");
+                /*
+                 * Set regulators to default values, ignore any errors,
+                 * we're going DOWN
+                 */
+                for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
+                        (void) ab3100_set_register_interruptible(abreg->ab3100,
+                                        ab3100_reg_init_order[i],
+                                        abreg->plfdata->reg_initvals[i]);
+                }
+
+                /* Setting LDO D to 0x00 cuts the power to the SoC */
+                return ab3100_set_register_interruptible(abreg->ab3100,
+                                                         AB3100_LDO_D, 0x00U);
+
+        }
+
+        /*
+         * All other regulators are handled here
+         */
+        err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
+                                                &regval);
+        if (err) {
+                dev_err(&reg->dev, "unable to get register 0x%x\n",
+                        abreg->regreg);
+                return err;
+        }
+        regval &= ~AB3100_REG_ON_MASK;
+        return ab3100_set_register_interruptible(abreg->ab3100, abreg->regreg,
+                                                 regval);
+}
+
+static int ab3100_is_enabled_regulator(struct regulator_dev *reg)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+        u8 regval;
+        int err;
+
+        err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
+                                                &regval);
+        if (err) {
+                dev_err(&reg->dev, "unable to get register 0x%x\n",
+                        abreg->regreg);
+                return err;
+        }
+
+        return regval & AB3100_REG_ON_MASK;
+}
+
+static int ab3100_list_voltage_regulator(struct regulator_dev *reg,
+                                         unsigned selector)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+
+        if (selector > abreg->voltages_len)
+                return -EINVAL;
+        return abreg->typ_voltages[selector];
+}
+
+static int ab3100_get_voltage_regulator(struct regulator_dev *reg)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+        u8 regval;
+        int err;
+
+        /* Return the voltage for fixed regulators immediately */
+        if (abreg->fixed_voltage)
+                return abreg->fixed_voltage;
+
+        /*
+         * For variable types, read out setting and index into
+         * supplied voltage list.
+         */
+        err = ab3100_get_register_interruptible(abreg->ab3100,
+                                                abreg->regreg, &regval);
+        if (err) {
+                dev_warn(&reg->dev,
+                         "failed to get regulator value in register %02x\n",
+                         abreg->regreg);
+                return err;
+        }
+
+        /* The 3 highest bits index voltages */
+        regval &= 0xE0;
+        regval >>= 5;
+
+        if (regval > abreg->voltages_len) {
+                dev_err(&reg->dev,
+                        "regulator register %02x contains an illegal voltage setting\n",
+                        abreg->regreg);
+                return -EINVAL;
+        }
+
+        return abreg->typ_voltages[regval];
+}
+
+static int ab3100_get_best_voltage_index(struct regulator_dev *reg,
+                                   int min_uV, int max_uV)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+        int i;
+        int bestmatch;
+        int bestindex;
+
+        /*
+         * Locate the minimum voltage fitting the criteria on
+         * this regulator. The switchable voltages are not
+         * in strict falling order so we need to check them
+         * all for the best match.
+         */
+        bestmatch = INT_MAX;
+        bestindex = -1;
+        for (i = 0; i < abreg->voltages_len; i++) {
+                if (abreg->typ_voltages[i] <= max_uV &&
+                    abreg->typ_voltages[i] >= min_uV &&
+                    abreg->typ_voltages[i] < bestmatch) {
+                        bestmatch = abreg->typ_voltages[i];
+                        bestindex = i;
+                }
+        }
+
+        if (bestindex < 0) {
+                dev_warn(&reg->dev, "requested %d<=x<=%d uV, out of range!\n",
+                         min_uV, max_uV);
+                return -EINVAL;
+        }
+        return bestindex;
+}
+
+static int ab3100_set_voltage_regulator(struct regulator_dev *reg,
+                                        int min_uV, int max_uV)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+        u8 regval;
+        int err;
+        int bestindex;
+
+        bestindex = ab3100_get_best_voltage_index(reg, min_uV, max_uV);
+        if (bestindex < 0)
+                return bestindex;
+
+        err = ab3100_get_register_interruptible(abreg->ab3100,
+                                                abreg->regreg, &regval);
+        if (err) {
+                dev_warn(&reg->dev,
+                         "failed to get regulator register %02x\n",
+                         abreg->regreg);
+                return err;
+        }
+
+        /* The highest three bits control the variable regulators */
+        regval &= ~0xE0;
+        regval |= (bestindex << 5);
+
+        err = ab3100_set_register_interruptible(abreg->ab3100,
+                                                abreg->regreg, regval);
+        if (err)
+                dev_warn(&reg->dev, "failed to set regulator register %02x\n",
+                        abreg->regreg);
+
+        return err;
+}
+
+static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg,
+                                                int uV)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+        u8 regval;
+        int err;
+        int bestindex;
+        u8 targetreg;
+
+        if (abreg->regreg == AB3100_LDO_E)
+                targetreg = AB3100_LDO_E_SLEEP;
+        else if (abreg->regreg == AB3100_BUCK)
+                targetreg = AB3100_BUCK_SLEEP;
+        else
+                return -EINVAL;
+
+        /* LDO E and BUCK have special suspend voltages you can set */
+        bestindex = ab3100_get_best_voltage_index(reg, uV, uV);
+
+        err = ab3100_get_register_interruptible(abreg->ab3100,
+                                                targetreg, &regval);
+        if (err) {
+                dev_warn(&reg->dev,
+                         "failed to get regulator register %02x\n",
+                         targetreg);
+                return err;
+        }
+
+        /* The highest three bits control the variable regulators */
+        regval &= ~0xE0;
+        regval |= (bestindex << 5);
+
+        err = ab3100_set_register_interruptible(abreg->ab3100,
+                                                targetreg, regval);
+        if (err)
+                dev_warn(&reg->dev, "failed to set regulator register %02x\n",
+                        abreg->regreg);
+
+        return err;
+}
+
+/*
+ * The external regulator can just define a fixed voltage.
+ */
+static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg)
+{
+        struct ab3100_regulator *abreg = reg->reg_data;
+
+        return abreg->plfdata->external_voltage;
+}
+
+static struct regulator_ops regulator_ops_fixed = {
+        .enable      = ab3100_enable_regulator,
+        .disable     = ab3100_disable_regulator,
+        .is_enabled  = ab3100_is_enabled_regulator,
+        .get_voltage = ab3100_get_voltage_regulator,
+};
+
+static struct regulator_ops regulator_ops_variable = {
+        .enable      = ab3100_enable_regulator,
+        .disable     = ab3100_disable_regulator,
+        .is_enabled  = ab3100_is_enabled_regulator,
+        .get_voltage = ab3100_get_voltage_regulator,
+        .set_voltage = ab3100_set_voltage_regulator,
+        .list_voltage = ab3100_list_voltage_regulator,
+};
+
+static struct regulator_ops regulator_ops_variable_sleepable = {
+        .enable      = ab3100_enable_regulator,
+        .disable     = ab3100_disable_regulator,
+        .is_enabled  = ab3100_is_enabled_regulator,
+        .get_voltage = ab3100_get_voltage_regulator,
+        .set_voltage = ab3100_set_voltage_regulator,
+        .set_suspend_voltage = ab3100_set_suspend_voltage_regulator,
+        .list_voltage = ab3100_list_voltage_regulator,
+};
+
+/*
+ * LDO EXT is an external regulator so it is really
+ * not possible to set any voltage locally here, AB3100
+ * is an on/off switch plain an simple. The external
+ * voltage is defined in the board set-up if any.
+ */
+static struct regulator_ops regulator_ops_external = {
+        .enable      = ab3100_enable_regulator,
+        .disable     = ab3100_disable_regulator,
+        .is_enabled  = ab3100_is_enabled_regulator,
+        .get_voltage = ab3100_get_voltage_regulator_external,
+};
+
+static struct regulator_desc
+ab3100_regulator_desc[AB3100_NUM_REGULATORS] = {
+        {
+                .name = "LDO_A",
+                .id   = AB3100_LDO_A,
+                .ops  = &regulator_ops_fixed,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "LDO_C",
+                .id   = AB3100_LDO_C,
+                .ops  = &regulator_ops_fixed,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "LDO_D",
+                .id   = AB3100_LDO_D,
+                .ops  = &regulator_ops_fixed,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "LDO_E",
+                .id   = AB3100_LDO_E,
+                .ops  = &regulator_ops_variable_sleepable,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "LDO_F",
+                .id   = AB3100_LDO_F,
+                .ops  = &regulator_ops_variable,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "LDO_G",
+                .id   = AB3100_LDO_G,
+                .ops  = &regulator_ops_variable,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "LDO_H",
+                .id   = AB3100_LDO_H,
+                .ops  = &regulator_ops_variable,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "LDO_K",
+                .id   = AB3100_LDO_K,
+                .ops  = &regulator_ops_variable,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "LDO_EXT",
+                .id   = AB3100_LDO_EXT,
+                .ops  = &regulator_ops_external,
+                .type = REGULATOR_VOLTAGE,
+        },
+        {
+                .name = "BUCK",
+                .id   = AB3100_BUCK,
+                .ops  = &regulator_ops_variable_sleepable,
+                .type = REGULATOR_VOLTAGE,
+        },
+};
+
+/*
+ * NOTE: the following functions are regulators pluralis - it is the
+ * binding to the AB3100 core driver and the parent platform device
+ * for all the different regulators.
+ */
+
+static int __init ab3100_regulators_probe(struct platform_device *pdev)
+{
+        struct ab3100_platform_data *plfdata = pdev->dev.platform_data;
+        struct ab3100 *ab3100 = platform_get_drvdata(pdev);
+        int err = 0;
+        u8 data;
+        int i;
+
+        /* Check chip state */
+        err = ab3100_get_register_interruptible(ab3100,
+                                                AB3100_LDO_D, &data);
+        if (err) {
+                dev_err(&pdev->dev, "could not read initial status of LDO_D\n");
+                return err;
+        }
+        if (data & 0x10)
+                dev_notice(&pdev->dev,
+                           "chip is already in active mode (Warm start)\n");
+        else
+                dev_notice(&pdev->dev,
+                           "chip is in inactive mode (Cold start)\n");
+
+        /* Set up regulators */
+        for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
+                err = ab3100_set_register_interruptible(ab3100,
+                                        ab3100_reg_init_order[i],
+                                        plfdata->reg_initvals[i]);
+                if (err) {
+                        dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
+                                err);
+                        return err;
+                }
+        }
+
+        if (err) {
+                dev_err(&pdev->dev,
+                        "LDO D regulator initialization failed with error %d\n",
+                        err);
+                return err;
+        }
+
+        /* Register the regulators */
+        for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
+                struct ab3100_regulator *reg = &ab3100_regulators[i];
+                struct regulator_dev *rdev;
+
+                /*
+                 * Initialize per-regulator struct.
+                 * Inherit platform data, this comes down from the
+                 * i2c boarddata, from the machine. So if you want to
+                 * see what it looks like for a certain machine, go
+                 * into the machine I2C setup.
+                 */
+                reg->ab3100 = ab3100;
+                reg->plfdata = plfdata;
+
+                /*
+                 * Register the regulator, pass around
+                 * the ab3100_regulator struct
+                 */
+                rdev = regulator_register(&ab3100_regulator_desc[i],
+                                          &pdev->dev,
+                                          &plfdata->reg_constraints[i],
+                                          reg);
+
+                if (IS_ERR(rdev)) {
+                        err = PTR_ERR(rdev);
+                        dev_err(&pdev->dev,
+                                "%s: failed to register regulator %s err %d\n",
+                                __func__, ab3100_regulator_desc[i].name,
+                                err);
+                        i--;
+                        /* remove the already registered regulators */
+                        while (i > 0) {
+                                regulator_unregister(ab3100_regulators[i].rdev);
+                                i--;
+                        }
+                        return err;
+                }
+
+                /* Then set a pointer back to the registered regulator */
+                reg->rdev = rdev;
+        }
+
+        return 0;
+}
+
+static int __exit ab3100_regulators_remove(struct platform_device *pdev)
+{
+        int i;
+
+        for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
+                struct ab3100_regulator *reg = &ab3100_regulators[i];
+
+                regulator_unregister(reg->rdev);
+        }
+        return 0;
+}
+
+static struct platform_driver ab3100_regulators_driver = {
+        .driver = {
+                .name  = "ab3100-regulators",
+                .owner = THIS_MODULE,
+        },
+        .probe = ab3100_regulators_probe,
+        .remove = __exit_p(ab3100_regulators_remove),
+};
+
+static __init int ab3100_regulators_init(void)
+{
+        return platform_driver_register(&ab3100_regulators_driver);
+}
+
+static __exit void ab3100_regulators_exit(void)
+{
+        platform_driver_register(&ab3100_regulators_driver);
+}
+
+subsys_initcall(ab3100_regulators_init);
+module_exit(ab3100_regulators_exit);
+
+MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>");
+MODULE_DESCRIPTION("AB3100 Regulator driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ab3100-regulators");
diff --git a/include/linux/mfd/ab3100.h b/include/linux/mfd/ab3100.h
index 3ead5cfb638c..e9aa4c9d749d 100644
--- a/include/linux/mfd/ab3100.h
+++ b/include/linux/mfd/ab3100.h
@@ -7,6 +7,7 @@
 
 #include <linux/device.h>
 #include <linux/workqueue.h>
+#include <linux/regulator/machine.h>
 
 #ifndef MFD_AB3100_H
 #define MFD_AB3100_H
@@ -57,6 +58,14 @@
 #define AB3100_STR_BATT_REMOVAL                         (0x40)
 #define AB3100_STR_VBUS                                 (0x80)
 
+/*
+ * AB3100 contains 8 regulators, one external regulator controller
+ * and a buck converter, further the LDO E and buck converter can
+ * have separate settings if they are in sleep mode, this is
+ * modeled as a separate regulator.
+ */
+#define AB3100_NUM_REGULATORS                           10
+
 /**
  * struct ab3100
  * @access_mutex: lock out concurrent accesses to the AB3100 registers
@@ -87,6 +96,25 @@ struct ab3100 {
         bool startup_events_read;
 };
 
+/**
+ * struct ab3100_platform_data
+ * Data supplied to initialize board connections to the AB3100
+ * @reg_constraints: regulator constraints for target board
+ *     the order of these constraints are: LDO A, C, D, E,
+ *     F, G, H, K, EXT and BUCK.
+ * @reg_initvals: initial values for the regulator registers
+ *     plus two sleep settings for LDO E and the BUCK converter.
+ *     exactly AB3100_NUM_REGULATORS+2 values must be sent in.
+ *     Order: LDO A, C, E, E sleep, F, G, H, K, EXT, BUCK,
+ *     BUCK sleep, LDO D. (LDO D need to be initialized last.)
+ * @external_voltage: voltage level of the external regulator.
+ */
+struct ab3100_platform_data {
+        struct regulator_init_data reg_constraints[AB3100_NUM_REGULATORS];
+        u8 reg_initvals[AB3100_NUM_REGULATORS+2];
+        int external_voltage;
+};
+
 int ab3100_set_register_interruptible(struct ab3100 *ab3100, u8 reg, u8 regval);
 int ab3100_get_register_interruptible(struct ab3100 *ab3100, u8 reg, u8 *regval);
 int ab3100_get_register_page_interruptible(struct ab3100 *ab3100,