regulators: ab8500: Add support of low voltage battery

Low voltage batteries have a wider voltage range with
lower operating voltages. Some consumers in the platform
may not work with the lower voltages and therefore need
an extra regulator to boost the voltage in this case.

This driver adds support for checking the consumers that
need higher voltage (Vaux1, 2 and 3 regulators, 3 V SIM)
and control the external buck/boost regulator
accordingly.

Note that to utilize the low voltage battery support,
the battery voltage thresholds must be changed. This
applies for the low battery voltage threshold of the
battery manager and the OTP setting for the AB8500
BattOk levels.

ST-Ericsson ID: 282517, 363432
ST-Ericsson Linux next: -
ST-Ericsson FOSS-OUT ID: Trivial

Change-Id: Ife07a622ec9748c027dbbd78b01e4ee7e92629ec
Signed-off-by: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/33616
Reviewed-by: QABUILD

10 files changed, 505 insertions, 21 deletions

diff --git a/arch/arm/configs/u8500_defconfig b/arch/arm/configs/u8500_defconfig
index 432ef2ee0e6..4e6858d42e2 100755
--- a/arch/arm/configs/u8500_defconfig
+++ b/arch/arm/configs/u8500_defconfig
@@ -235,6 +235,7 @@ CONFIG_MFD_DB8500_PRCMU=y
 CONFIG_REGULATOR_DEBUG=y
 CONFIG_REGULATOR_VIRTUAL_CONSUMER=y
 CONFIG_REGULATOR_AB8500=y
+CONFIG_REGULATOR_AB8500_EXT=y
 CONFIG_REGULATOR_AB8500_DEBUG=y
 CONFIG_REGULATOR_DB8500_PRCMU=y
 CONFIG_MEDIA_SUPPORT=y
diff --git a/arch/arm/mach-ux500/board-mop500-regulators.c b/arch/arm/mach-ux500/board-mop500-regulators.c
index 37eec12f9f7..41a6f42a719 100644
--- a/arch/arm/mach-ux500/board-mop500-regulators.c
+++ b/arch/arm/mach-ux500/board-mop500-regulators.c
@@ -395,6 +395,7 @@ static struct ab8500_regulator_reg_init ab8500_reg_init[] = {
 static struct regulator_init_data ab8500_regulators[AB8500_NUM_REGULATORS] = {
 	/* supplies to the display/camera */
 	[AB8500_LDO_AUX1] = {
+		.supply_regulator = "ab8500-ext-supply3",
 		.constraints = {
 			.name = "V-DISPLAY",
 			.min_uV = 2800000,
@@ -408,6 +409,7 @@ static struct regulator_init_data ab8500_regulators[AB8500_NUM_REGULATORS] = {
 	},
 	/* supplies to the on-board eMMC */
 	[AB8500_LDO_AUX2] = {
+		.supply_regulator = "ab8500-ext-supply3",
 		.constraints = {
 			.name = "V-eMMC1",
 			.min_uV = 1100000,
@@ -423,6 +425,7 @@ static struct regulator_init_data ab8500_regulators[AB8500_NUM_REGULATORS] = {
 	},
 	/* supply for VAUX3, supplies to SDcard slots */
 	[AB8500_LDO_AUX3] = {
+		.supply_regulator = "ab8500-ext-supply3",
 		.constraints = {
 			.name = "V-MMC-SD",
 			.min_uV = 1100000,
@@ -529,9 +532,36 @@ static struct regulator_init_data ab8500_regulators[AB8500_NUM_REGULATORS] = {
 	},
 };
 
+/* supply for VextSupply3 */
+static struct regulator_consumer_supply ab8500_ext_supply3_consumers[] = {
+	/* SIM supply for 3 V SIM cards */
+	REGULATOR_SUPPLY("vinvsim", "sim-detect.0"),
+};
+
+/*
+ * AB8500 external regulators
+ */
+static struct regulator_init_data ab8500_ext_regulators[] = {
+	/* fixed Vbat supplies VSMPS3_EXT_3V4 and VSMPS4_EXT_3V4 */
+	[AB8500_EXT_SUPPLY3] = {
+		.constraints = {
+			.name = "ab8500-ext-supply3",
+			.min_uV = 3400000,
+			.max_uV = 3400000,
+			.valid_ops_mask = REGULATOR_CHANGE_STATUS,
+			.boot_on = 1,
+		},
+		.num_consumer_supplies =
+			ARRAY_SIZE(ab8500_ext_supply3_consumers),
+		.consumer_supplies = ab8500_ext_supply3_consumers,
+	},
+};
+
 struct ab8500_regulator_platform_data ab8500_regulator_plat_data = {
 	.reg_init               = ab8500_reg_init,
 	.num_reg_init           = ARRAY_SIZE(ab8500_reg_init),
 	.regulator              = ab8500_regulators,
 	.num_regulator          = ARRAY_SIZE(ab8500_regulators),
+	.ext_regulator          = ab8500_ext_regulators,
+	.num_ext_regulator      = ARRAY_SIZE(ab8500_ext_regulators),
 };
diff --git a/arch/arm/mach-ux500/board-mop500.c b/arch/arm/mach-ux500/board-mop500.c
index 5afa0038194..876199f2407 100644
--- a/arch/arm/mach-ux500/board-mop500.c
+++ b/arch/arm/mach-ux500/board-mop500.c
@@ -847,7 +847,7 @@ static struct sim_detect_platform_data sim_detect_pdata = {
 	.irq_num		= MOP500_AB8500_VIR_GPIO_IRQ(6),
 };
 struct platform_device u8500_sim_detect_device = {
-	.name	= "sim_detect",
+	.name	= "sim-detect",
 	.id	= 0,
 	.dev	= {
 			.platform_data          = &sim_detect_pdata,
diff --git a/drivers/misc/sim_detect.c b/drivers/misc/sim_detect.c
index c267fe95ee3..213645ca46d 100644
--- a/drivers/misc/sim_detect.c
+++ b/drivers/misc/sim_detect.c
@@ -2,29 +2,130 @@
  * Copyright (C) ST-Ericsson SA 2011
  *
  * Author: BIBEK BASU <bibek.basu@stericsson.com>
+ *
  * License terms: GNU General Public License (GPL) version 2
  */
+
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/err.h>
+#include <linux/mutex.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>
 #include <linux/hrtimer.h>
 #include <linux/workqueue.h>
+#include <linux/uaccess.h>
 #include <linux/modem/modem_client.h>
 #include <mach/sim_detect.h>
+#include <linux/regulator/consumer.h>
 
 /* time in millisec */
 #define TIMER_DELAY	10
+
 struct sim_detect{
 	struct work_struct	timer_expired;
 	struct device	*dev;
 	struct modem *modem;
 	struct hrtimer timer;
+	struct mutex lock;
+	int voltage;
+	struct regulator *vinvsim_regulator;
+	bool regulator_enabled;
+};
+
+static ssize_t show_voltage(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	struct sim_detect *data = dev_get_drvdata(dev);
+	int ret, len;
+
+	ret = mutex_lock_interruptible(&data->lock);
+	if (ret < 0)
+		return ret;
+
+	len = sprintf(buf, "%i\n", data->voltage);
+
+	mutex_unlock(&data->lock);
+
+	return len;
+}
+
+static ssize_t write_voltage(struct device *dev, struct device_attribute *attr,
+			     const char *buf, size_t count)
+{
+	struct sim_detect *sim_detect = dev_get_drvdata(dev);
+	long val;
+	int ret;
+
+	/* check input */
+	if (strict_strtol(buf, 0, &val) != 0) {
+		dev_err(dev, "Invalid voltage class configured.\n");
+		return count;
+	}
+
+	switch (val) {
+	case -1:
+	case 0:
+	case 1800000:
+	case 3000000:
+		break;
+	default:
+		dev_err(dev, "Invalid voltage class configured.\n");
+		return count;
+	}
+
+	/* lock */
+	ret = mutex_lock_interruptible(&sim_detect->lock);
+	if (ret < 0)
+		return ret;
+
+	/* update state */
+	sim_detect->voltage = val;
+
+	/* call regulator */
+	switch (sim_detect->voltage) {
+	case 0:
+		/* SIM voltage is unknown, turn on regulator for 3 V SIM */
+	case 3000000:
+		/* Vinvsim supply is used only for 3 V SIM */
+		if (!sim_detect->regulator_enabled) {
+			ret = regulator_enable(sim_detect->vinvsim_regulator);
+			if (ret) {
+				dev_err(dev, "Failed to enable regulator.\n");
+				goto out_unlock;
+			}
+			sim_detect->regulator_enabled = true;
+		}
+		break;
+	case 1800000:
+	case -1:
+		/* Vbatvsim is used otherwise */
+		if (sim_detect->regulator_enabled) {
+			regulator_disable(sim_detect->vinvsim_regulator);
+			sim_detect->regulator_enabled = false;
+		}
+	}
+
+out_unlock:
+	/* unlock and return */
+	mutex_unlock(&sim_detect->lock);
+
+	return count;
+}
+
+static DEVICE_ATTR(voltage, 0666, show_voltage, write_voltage);
+
+static struct attribute *sim_attributes[] = {
+	&dev_attr_voltage.attr,
+	NULL
+};
+
+static const struct attribute_group sim_attr_group = {
+	.attrs	= sim_attributes,
 };
 
 static void inform_modem_release(struct work_struct *work)
@@ -87,6 +188,7 @@ static const struct dev_pm_ops sim_detect_dev_pm_ops = {
 };
 #endif
 
+
 static int __devinit sim_detect_probe(struct platform_device *pdev)
 {
 	struct sim_detect_platform_data *plat = dev_get_platdata(&pdev->dev);
@@ -98,25 +200,61 @@ static int __devinit sim_detect_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to allocate memory\n");
 		return -ENOMEM;
 	}
+
+	/* initialize data */
+	mutex_init(&sim_detect->lock);
+	sim_detect->voltage = 0;
+
 	sim_detect->dev = &pdev->dev;
 	INIT_WORK(&sim_detect->timer_expired, inform_modem_release);
 	hrtimer_init(&sim_detect->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	sim_detect->timer.function = timer_callback;
+
 	sim_detect->modem = modem_get(sim_detect->dev, "u8500-shrm-modem");
 	if (IS_ERR(sim_detect->modem)) {
 		ret = PTR_ERR(sim_detect->modem);
 		dev_err(sim_detect->dev, "Could not retrieve the modem\n");
 		goto out_free;
 	}
+
+	/* set drvdata */
 	platform_set_drvdata(pdev, sim_detect);
+
+	/* request irq */
 	ret = request_threaded_irq(plat->irq_num,
 		       NULL, sim_activity_irq,
 		       IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 		       "sim activity", sim_detect);
 	if (ret < 0)
+		goto out_put_modem;
+
+	/* get regulator */
+	sim_detect->regulator_enabled = false;
+	sim_detect->vinvsim_regulator = regulator_get(sim_detect->dev,
+							 "vinvsim");
+	if (IS_ERR(sim_detect->vinvsim_regulator)) {
+		dev_err(&pdev->dev,
+			"Failed to get regulator. (dev_name %s).\n",
+			dev_name(sim_detect->dev));
+		ret = PTR_ERR(sim_detect->vinvsim_regulator);
 		goto out_free_irq;
+	}
+
+	/* register sysfs entry */
+	ret = sysfs_create_group(&pdev->dev.kobj, &sim_attr_group);
+	if (ret != 0) {
+		dev_err(&pdev->dev,
+			"Failed to create attribute group: %d\n", ret);
+		goto out_free_regulator;
+	}
+
 	return 0;
+
+out_free_regulator:
+	regulator_put(sim_detect->vinvsim_regulator);
 out_free_irq:
+	free_irq(plat->irq_num, sim_detect);
+out_put_modem:
 	modem_put(sim_detect->modem);
 	platform_set_drvdata(pdev, NULL);
 out_free:
@@ -128,6 +266,8 @@ static int __devexit sim_detect_remove(struct platform_device *pdev)
 {
 	struct sim_detect *sim_detect = platform_get_drvdata(pdev);
 
+	sysfs_remove_group(&pdev->dev.kobj, &sim_attr_group);
+	regulator_put(sim_detect->vinvsim_regulator);
 	modem_put(sim_detect->modem);
 	platform_set_drvdata(pdev, NULL);
 	kfree(sim_detect);
@@ -136,7 +276,7 @@ static int __devexit sim_detect_remove(struct platform_device *pdev)
 
 static struct platform_driver sim_detect_driver = {
 	.driver = {
-		.name = "sim_detect",
+		.name = "sim-detect",
 		.owner = THIS_MODULE,
 #ifdef CONFIG_PM
 		.pm = &sim_detect_dev_pm_ops,
@@ -160,5 +300,5 @@ module_exit(sim_detect_exit);
 
 MODULE_AUTHOR("BIBEK BASU <bibek.basu@stericsson.com>");
 MODULE_DESCRIPTION("Detects SIM Hot Swap and wakes modem");
-MODULE_ALIAS("SIM DETECT INTERRUPT driver");
+MODULE_ALIAS("platform:sim-detect");
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index ec1cee88683..138edc60efc 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -281,6 +281,14 @@ config REGULATOR_AB8500
 	  This driver supports the regulators found on the ST-Ericsson mixed
 	  signal AB8500 PMIC
 
+config REGULATOR_AB8500_EXT
+	bool "ST-Ericsson AB8500 External Regulators"
+	depends on REGULATOR_AB8500
+	default y if REGULATOR_AB8500
+	help
+	  This driver supports the external regulator controls found on the
+	  ST-Ericsson mixed signal AB8500 PMIC
+
 config REGULATOR_DBX500_PRCMU
 	bool
 
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index aff7d7b213e..0f94c582d93 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -42,6 +42,7 @@ obj-$(CONFIG_REGULATOR_88PM8607) += 88pm8607.o
 obj-$(CONFIG_REGULATOR_ISL6271A) += isl6271a-regulator.o
 obj-$(CONFIG_REGULATOR_AB5500) += ab5500.o
 obj-$(CONFIG_REGULATOR_AB8500)	+= ab8500.o
+obj-$(CONFIG_REGULATOR_AB8500_EXT) += ab8500-ext.o
 obj-$(CONFIG_REGULATOR_DBX500_PRCMU) += dbx500-prcmu.o
 obj-$(CONFIG_REGULATOR_DB5500_PRCMU) += db5500-prcmu.o
 obj-$(CONFIG_REGULATOR_DB8500_PRCMU) += db8500-prcmu.o
diff --git a/drivers/regulator/ab8500-debug.c b/drivers/regulator/ab8500-debug.c
index 661386890af..76eff94d136 100644
--- a/drivers/regulator/ab8500-debug.c
+++ b/drivers/regulator/ab8500-debug.c
@@ -1524,14 +1524,13 @@ static struct ab8500_force_reg ab8500_force_reg[] = {
 		/*
 		 * ExtSupplyRegu (HSI: 0x2a on v2-v40?)
 		 * OTP: 0x15, HSI: 0x28, suspend: 0x28/0x3f (value/mask)
-		 * [5:4] VExtSupply3Regu[1:0] = 10 = Vext3 off
 		 * [3:2] VExtSupply2Regu[1:0] = 10 = Vext2 in HW control
 		 * [1:0] VExtSupply1Regu[1:0] = 00 = Vext1 off
 		 */
 		.name = "ExtSupplyRegu",
 		.bank = 0x04,
 		.addr = 0x08,
-		.mask = 0x3f,
+		.mask = 0x0f,
 		.val  = 0x08,
 	},
 	{
@@ -1750,21 +1749,6 @@ static int __devinit ab8500_regulator_debug_probe(struct platform_device *plf)
 		}
 	}
 
-	/*
-	 * find ExtSupplyRegu register (bank 0x04, addr 0x08)
-	 * and update value (Vext3 in high power).
-	 */
-	for (i = 0; i < ARRAY_SIZE(ab8500_force_reg); i++) {
-		if (ab8500_force_reg[i].bank == 0x04 &&
-		    ab8500_force_reg[i].addr == 0x08) {
-			u8 val, val_mask = 0x30;
-
-			val = ab8500_force_reg[i].val;
-			val = (val & ~val_mask) | (0x10 & val_mask);
-			ab8500_force_reg[i].val = val;
-		}
-	}
-
 	/* make suspend-force default if board profile is v5x-power */
 	boot_info_backupram = ioremap(BOOT_INFO_BACKUPRAM1, 0x4);
 
diff --git a/drivers/regulator/ab8500-ext.c b/drivers/regulator/ab8500-ext.c
new file mode 100644
index 00000000000..adf8e6b83f2
--- /dev/null
+++ b/drivers/regulator/ab8500-ext.c
@@ -0,0 +1,292 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * License Terms: GNU General Public License v2
+ *
+ * Authors: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
+ *
+ * This file is based on drivers/regulator/ab8500.c
+ *
+ * AB8500 external regulators
+ *
+ * ab8500-ext supports the following regulators:
+ * - VextSupply3
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/mfd/abx500.h>
+#include <linux/mfd/ab8500.h>
+#include <linux/regulator/ab8500.h>
+
+/**
+ * struct ab8500_ext_regulator_info - ab8500 regulator information
+ * @dev: device pointer
+ * @desc: regulator description
+ * @regulator_dev: regulator device
+ * @is_enabled: status of regulator (on/off)
+ * @fixed_uV: typical voltage (for fixed voltage supplies)
+ * @update_bank: bank to control on/off
+ * @update_reg: register to control on/off
+ * @update_mask: mask to enable/disable and set mode of regulator
+ * @update_val: bits holding the regulator current mode
+ * @update_val_en: bits to set EN pin active (LPn pin deactive)
+ *                 normally this means high power mode
+ * @update_val_en_lp: bits to set EN pin active and LPn pin active
+ *                    normally this means low power mode
+ * @delay: startup delay in ms
+ */
+struct ab8500_ext_regulator_info {
+	struct device *dev;
+	struct regulator_desc desc;
+	struct regulator_dev *regulator;
+	bool is_enabled;
+	int fixed_uV;
+	u8 update_bank;
+	u8 update_reg;
+	u8 update_mask;
+	u8 update_val;
+	u8 update_val_en;
+	u8 update_val_en_lp;
+};
+
+static int ab8500_ext_regulator_enable(struct regulator_dev *rdev)
+{
+	int ret;
+	struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+
+	if (info == NULL) {
+		dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+		return -EINVAL;
+	}
+
+	ret = abx500_mask_and_set_register_interruptible(info->dev,
+		info->update_bank, info->update_reg,
+		info->update_mask, info->update_val);
+	if (ret < 0)
+		dev_err(rdev_get_dev(rdev),
+			"couldn't set enable bits for regulator\n");
+
+	info->is_enabled = true;
+
+	dev_dbg(rdev_get_dev(rdev), "%s-enable (bank, reg, mask, value):"
+		" 0x%02x, 0x%02x, 0x%02x, 0x%02x\n",
+		info->desc.name, info->update_bank, info->update_reg,
+		info->update_mask, info->update_val);
+
+	return ret;
+}
+
+static int ab8500_ext_regulator_disable(struct regulator_dev *rdev)
+{
+	int ret;
+	struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+
+	if (info == NULL) {
+		dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+		return -EINVAL;
+	}
+
+	ret = abx500_mask_and_set_register_interruptible(info->dev,
+		info->update_bank, info->update_reg,
+		info->update_mask, 0x0);
+	if (ret < 0)
+		dev_err(rdev_get_dev(rdev),
+			"couldn't set disable bits for regulator\n");
+
+	info->is_enabled = false;
+
+	dev_dbg(rdev_get_dev(rdev), "%s-disable (bank, reg, mask, value):"
+		" 0x%02x, 0x%02x, 0x%02x, 0x%02x\n",
+		info->desc.name, info->update_bank, info->update_reg,
+		info->update_mask, 0x0);
+
+	return ret;
+}
+
+static int ab8500_ext_regulator_is_enabled(struct regulator_dev *rdev)
+{
+	int ret;
+	struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+	u8 regval;
+
+	if (info == NULL) {
+		dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+		return -EINVAL;
+	}
+
+	ret = abx500_get_register_interruptible(info->dev,
+		info->update_bank, info->update_reg, &regval);
+	if (ret < 0) {
+		dev_err(rdev_get_dev(rdev),
+			"couldn't read 0x%x register\n", info->update_reg);
+		return ret;
+	}
+
+	dev_dbg(rdev_get_dev(rdev), "%s-is_enabled (bank, reg, mask, value):"
+		" 0x%02x, 0x%02x, 0x%02x, 0x%02x\n",
+		info->desc.name, info->update_bank, info->update_reg,
+		info->update_mask, regval);
+
+	if (regval & info->update_mask)
+		info->is_enabled = true;
+	else
+		info->is_enabled = false;
+
+	return info->is_enabled;
+}
+
+static int ab8500_ext_fixed_get_voltage(struct regulator_dev *rdev)
+{
+	struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+
+	if (info == NULL) {
+		dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+		return -EINVAL;
+	}
+
+	return info->fixed_uV;
+}
+
+static int ab8500_ext_list_voltage(struct regulator_dev *rdev,
+				   unsigned selector)
+{
+	struct ab8500_ext_regulator_info *info = rdev_get_drvdata(rdev);
+
+	if (info == NULL) {
+		dev_err(rdev_get_dev(rdev), "regulator info null pointer\n");
+		return -EINVAL;
+	}
+
+	/* return the uV for the fixed regulators */
+	if (info->fixed_uV)
+		return info->fixed_uV;
+
+	return -EINVAL;
+}
+
+static struct regulator_ops ab8500_ext_regulator_ops = {
+	.enable			= ab8500_ext_regulator_enable,
+	.disable		= ab8500_ext_regulator_disable,
+	.is_enabled		= ab8500_ext_regulator_is_enabled,
+	.get_voltage		= ab8500_ext_fixed_get_voltage,
+	.list_voltage		= ab8500_ext_list_voltage,
+};
+
+
+static struct ab8500_ext_regulator_info
+		ab8500_ext_regulator_info[AB8500_NUM_EXT_REGULATORS] = {
+	[AB8500_EXT_SUPPLY3] = {
+		.desc = {
+			.name		= "VEXTSUPPLY3",
+			.ops		= &ab8500_ext_regulator_ops,
+			.type		= REGULATOR_VOLTAGE,
+			.id		= AB8500_EXT_SUPPLY3,
+			.owner		= THIS_MODULE,
+			.n_voltages	= 1,
+		},
+		.fixed_uV		= 3400000,
+		.update_bank		= 0x04,
+		.update_reg		= 0x08,
+		.update_mask		= 0x30,
+		.update_val		= 0x10,
+		.update_val_en		= 0x10,
+		.update_val_en_lp	= 0x30,
+	},
+};
+
+__devinit int ab8500_ext_regulator_init(struct platform_device *pdev)
+{
+	struct ab8500 *ab8500 = dev_get_drvdata(pdev->dev.parent);
+	struct ab8500_platform_data *ppdata;
+	struct ab8500_regulator_platform_data *pdata;
+	int i, err;
+
+	if (!ab8500) {
+		dev_err(&pdev->dev, "null mfd parent\n");
+		return -EINVAL;
+	}
+	ppdata = dev_get_platdata(ab8500->dev);
+	if (!ppdata) {
+		dev_err(&pdev->dev, "null parent pdata\n");
+		return -EINVAL;
+	}
+
+	pdata = ppdata->regulator;
+	if (!pdata) {
+		dev_err(&pdev->dev, "null pdata\n");
+		return -EINVAL;
+	}
+
+	/* make sure the platform data has the correct size */
+	if (pdata->num_ext_regulator != ARRAY_SIZE(ab8500_ext_regulator_info)) {
+		dev_err(&pdev->dev, "Configuration error: size mismatch.\n");
+		return -EINVAL;
+	}
+
+	/* check for AB8500 2.x */
+	if (abx500_get_chip_id(&pdev->dev) < 0x30) {
+		struct ab8500_ext_regulator_info *info;
+
+		/* VextSupply3LPn is inverted on AB8500 2.x */
+		info = &ab8500_ext_regulator_info[AB8500_EXT_SUPPLY3];
+		info->update_val = 0x30;
+		info->update_val_en = 0x30;
+		info->update_val_en_lp = 0x10;
+	}
+
+	/* register all regulators */
+	for (i = 0; i < ARRAY_SIZE(ab8500_ext_regulator_info); i++) {
+		struct ab8500_ext_regulator_info *info = NULL;
+
+		/* assign per-regulator data */
+		info = &ab8500_ext_regulator_info[i];
+		info->dev = &pdev->dev;
+
+		/* register regulator with framework */
+		info->regulator = regulator_register(&info->desc, &pdev->dev,
+				&pdata->ext_regulator[i], info);
+		if (IS_ERR(info->regulator)) {
+			err = PTR_ERR(info->regulator);
+			dev_err(&pdev->dev, "failed to register regulator %s\n",
+					info->desc.name);
+			/* when we fail, un-register all earlier regulators */
+			while (--i >= 0) {
+				info = &ab8500_ext_regulator_info[i];
+				regulator_unregister(info->regulator);
+			}
+			return err;
+		}
+
+		dev_dbg(rdev_get_dev(info->regulator),
+			"%s-probed\n", info->desc.name);
+	}
+
+	return 0;
+}
+
+__devexit int ab8500_ext_regulator_exit(struct platform_device *pdev)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ab8500_ext_regulator_info); i++) {
+		struct ab8500_ext_regulator_info *info = NULL;
+		info = &ab8500_ext_regulator_info[i];
+
+		dev_vdbg(rdev_get_dev(info->regulator),
+			"%s-remove\n", info->desc.name);
+
+		regulator_unregister(info->regulator);
+	}
+
+	return 0;
+}
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Bengt Jonsson <bengt.g.jonsson@stericsson.com>");
+MODULE_DESCRIPTION("AB8500 external regulator driver");
+MODULE_ALIAS("platform:ab8500-ext-regulator");
diff --git a/drivers/regulator/ab8500.c b/drivers/regulator/ab8500.c
index 3ad27a9715d..0480f55b101 100644
--- a/drivers/regulator/ab8500.c
+++ b/drivers/regulator/ab8500.c
@@ -1162,6 +1162,11 @@ static __devinit int ab8500_regulator_probe(struct platform_device *pdev)
 		}
 	}
 
+	/* register external regulators (before Vaux1, 2 and 3) */
+	err = ab8500_ext_regulator_init(pdev);
+	if (err)
+		return err;
+
 	/* register all regulators */
 	for (i = 0; i < ARRAY_SIZE(ab8500_regulator_info); i++) {
 		struct ab8500_regulator_info *info = NULL;
@@ -1206,7 +1211,7 @@ static __devinit int ab8500_regulator_probe(struct platform_device *pdev)
 
 static __devexit int ab8500_regulator_remove(struct platform_device *pdev)
 {
-	int i;
+	int i, err;
 
 	for (i = 0; i < ARRAY_SIZE(ab8500_regulator_info); i++) {
 		struct ab8500_regulator_info *info = NULL;
@@ -1218,6 +1223,11 @@ static __devexit int ab8500_regulator_remove(struct platform_device *pdev)
 		regulator_unregister(info->regulator);
 	}
 
+	/* remove external regulators (after Vaux1, 2 and 3) */
+	err = ab8500_ext_regulator_exit(pdev);
+	if (err)
+		return err;
+
 	return 0;
 }
 
diff --git a/include/linux/regulator/ab8500.h b/include/linux/regulator/ab8500.h
index 095d94af589..df1e148da73 100644
--- a/include/linux/regulator/ab8500.h
+++ b/include/linux/regulator/ab8500.h
@@ -10,6 +10,8 @@
 #ifndef __LINUX_MFD_AB8500_REGULATOR_H
 #define __LINUX_MFD_AB8500_REGULATOR_H
 
+#include <linux/platform_device.h>
+
 /* AB8500 regulators */
 enum ab8500_regulator_id {
 	AB8500_LDO_AUX1,
@@ -86,11 +88,27 @@ enum ab8500_regulator_reg {
 	AB8500_NUM_REGULATOR_REGISTERS,
 };
 
+/* AB8500 external regulators */
+enum ab8500_ext_regulator_id {
+	AB8500_EXT_SUPPLY3,
+	AB8500_NUM_EXT_REGULATORS,
+};
+
 struct ab8500_regulator_platform_data {
 	int num_reg_init;
 	struct ab8500_regulator_reg_init *reg_init;
 	int num_regulator;
 	struct regulator_init_data *regulator;
+	int num_ext_regulator;
+	struct regulator_init_data *ext_regulator;
 };
 
+#ifdef CONFIG_REGULATOR_AB8500_EXT
+__devinit int ab8500_ext_regulator_init(struct platform_device *pdev);
+__devexit int ab8500_ext_regulator_exit(struct platform_device *pdev);
+#else
+inline __devinit int ab8500_ext_regulator_init(struct platform_device *pdev) {}
+inline __devexit int ab8500_ext_regulator_exit(struct platform_device *pdev) {}
+#endif
+
 #endif