regulator: Add WM831x LDO support

The WM831x series of devices provide three types of LDO:

 - General purpose LDOs supporting voltages from 0.9-3.3V
 - High performance analogue LDOs supporting voltages from 1-3.5V
 - Very low power consumption LDOs intended to support always on
   functionality.

This patch adds support for all three kinds of LDO. Each regulator
is probed as an individual platform device with resources used to
provide the register map location of the regulator. Mixed hardware
and software control of regulators is not current supported.

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

2 files changed, 853 insertions, 0 deletions

diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index b1d2b82..a0a635f 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o
 obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl4030-regulator.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
+obj-$(CONFIG_REGULATOR_WM831X) += wm831x-ldo.o
 obj-$(CONFIG_REGULATOR_WM8350) += wm8350-regulator.o
 obj-$(CONFIG_REGULATOR_WM8400) += wm8400-regulator.o
 obj-$(CONFIG_REGULATOR_DA903X)	+= da903x.o
diff --git a/drivers/regulator/wm831x-ldo.c b/drivers/regulator/wm831x-ldo.c
new file mode 100644
index 0000000..bb61aed
--- /dev/null
+++ b/drivers/regulator/wm831x-ldo.c
@@ -0,0 +1,852 @@
+/*
+ * wm831x-ldo.c  --  LDO driver for the WM831x series
+ *
+ * Copyright 2009 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ *  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/moduleparam.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+
+#include <linux/mfd/wm831x/core.h>
+#include <linux/mfd/wm831x/regulator.h>
+#include <linux/mfd/wm831x/pdata.h>
+
+#define WM831X_LDO_MAX_NAME 6
+
+#define WM831X_LDO_CONTROL       0
+#define WM831X_LDO_ON_CONTROL    1
+#define WM831X_LDO_SLEEP_CONTROL 2
+
+#define WM831X_ALIVE_LDO_ON_CONTROL    0
+#define WM831X_ALIVE_LDO_SLEEP_CONTROL 1
+
+struct wm831x_ldo {
+	char name[WM831X_LDO_MAX_NAME];
+	struct regulator_desc desc;
+	int base;
+	struct wm831x *wm831x;
+	struct regulator_dev *regulator;
+};
+
+/*
+ * Shared
+ */
+
+static int wm831x_ldo_is_enabled(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int mask = 1 << rdev_get_id(rdev);
+	int reg;
+
+	reg = wm831x_reg_read(wm831x, WM831X_LDO_ENABLE);
+	if (reg < 0)
+		return reg;
+
+	if (reg & mask)
+		return 1;
+	else
+		return 0;
+}
+
+static int wm831x_ldo_enable(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int mask = 1 << rdev_get_id(rdev);
+
+	return wm831x_set_bits(wm831x, WM831X_LDO_ENABLE, mask, mask);
+}
+
+static int wm831x_ldo_disable(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int mask = 1 << rdev_get_id(rdev);
+
+	return wm831x_set_bits(wm831x, WM831X_LDO_ENABLE, mask, 0);
+}
+
+static irqreturn_t wm831x_ldo_uv_irq(int irq, void *data)
+{
+	struct wm831x_ldo *ldo = data;
+
+	regulator_notifier_call_chain(ldo->regulator,
+				      REGULATOR_EVENT_UNDER_VOLTAGE,
+				      NULL);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * General purpose LDOs
+ */
+
+#define WM831X_GP_LDO_SELECTOR_LOW 0xe
+#define WM831X_GP_LDO_MAX_SELECTOR 0x1f
+
+static int wm831x_gp_ldo_list_voltage(struct regulator_dev *rdev,
+				      unsigned int selector)
+{
+	/* 0.9-1.6V in 50mV steps */
+	if (selector <= WM831X_GP_LDO_SELECTOR_LOW)
+		return 900000 + (selector * 50000);
+	/* 1.7-3.3V in 50mV steps */
+	if (selector <= WM831X_GP_LDO_MAX_SELECTOR)
+		return 1600000 + ((selector - WM831X_GP_LDO_SELECTOR_LOW)
+				  * 100000);
+	return -EINVAL;
+}
+
+static int wm831x_gp_ldo_set_voltage_int(struct regulator_dev *rdev, int reg,
+					 int min_uV, int max_uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int vsel, ret;
+
+	if (min_uV < 900000)
+		vsel = 0;
+	else if (min_uV < 1700000)
+		vsel = ((min_uV - 900000) / 50000);
+	else
+		vsel = ((min_uV - 1700000) / 100000)
+			+ WM831X_GP_LDO_SELECTOR_LOW + 1;
+
+	ret = wm831x_gp_ldo_list_voltage(rdev, vsel);
+	if (ret < 0)
+		return ret;
+	if (ret < min_uV || ret > max_uV)
+		return -EINVAL;
+
+	return wm831x_set_bits(wm831x, reg, WM831X_LDO1_ON_VSEL_MASK, vsel);
+}
+
+static int wm831x_gp_ldo_set_voltage(struct regulator_dev *rdev,
+				     int min_uV, int max_uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	int reg = ldo->base + WM831X_LDO_ON_CONTROL;
+
+	return wm831x_gp_ldo_set_voltage_int(rdev, reg, min_uV, max_uV);
+}
+
+static int wm831x_gp_ldo_set_suspend_voltage(struct regulator_dev *rdev,
+					     int uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	int reg = ldo->base + WM831X_LDO_SLEEP_CONTROL;
+
+	return wm831x_gp_ldo_set_voltage_int(rdev, reg, uV, uV);
+}
+
+static int wm831x_gp_ldo_get_voltage(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int reg = ldo->base + WM831X_LDO_ON_CONTROL;
+	int ret;
+
+	ret = wm831x_reg_read(wm831x, reg);
+	if (ret < 0)
+		return ret;
+
+	ret &= WM831X_LDO1_ON_VSEL_MASK;
+
+	return wm831x_gp_ldo_list_voltage(rdev, ret);
+}
+
+static unsigned int wm831x_gp_ldo_get_mode(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int ctrl_reg = ldo->base + WM831X_LDO_CONTROL;
+	int on_reg = ldo->base + WM831X_LDO_ON_CONTROL;
+	unsigned int ret;
+
+	ret = wm831x_reg_read(wm831x, on_reg);
+	if (ret < 0)
+		return 0;
+
+	if (!(ret & WM831X_LDO1_ON_MODE))
+		return REGULATOR_MODE_NORMAL;
+
+	ret = wm831x_reg_read(wm831x, ctrl_reg);
+	if (ret < 0)
+		return 0;
+
+	if (ret & WM831X_LDO1_LP_MODE)
+		return REGULATOR_MODE_STANDBY;
+	else
+		return REGULATOR_MODE_IDLE;
+}
+
+static int wm831x_gp_ldo_set_mode(struct regulator_dev *rdev,
+				  unsigned int mode)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int ctrl_reg = ldo->base + WM831X_LDO_CONTROL;
+	int on_reg = ldo->base + WM831X_LDO_ON_CONTROL;
+	int ret;
+
+
+	switch (mode) {
+	case REGULATOR_MODE_NORMAL:
+		ret = wm831x_set_bits(wm831x, on_reg,
+				      WM831X_LDO1_ON_MODE, 0);
+		if (ret < 0)
+			return ret;
+		break;
+
+	case REGULATOR_MODE_IDLE:
+		ret = wm831x_set_bits(wm831x, ctrl_reg,
+				      WM831X_LDO1_LP_MODE,
+				      WM831X_LDO1_LP_MODE);
+		if (ret < 0)
+			return ret;
+
+		ret = wm831x_set_bits(wm831x, on_reg,
+				      WM831X_LDO1_ON_MODE,
+				      WM831X_LDO1_ON_MODE);
+		if (ret < 0)
+			return ret;
+
+	case REGULATOR_MODE_STANDBY:
+		ret = wm831x_set_bits(wm831x, ctrl_reg,
+				      WM831X_LDO1_LP_MODE, 0);
+		if (ret < 0)
+			return ret;
+
+		ret = wm831x_set_bits(wm831x, on_reg,
+				      WM831X_LDO1_ON_MODE,
+				      WM831X_LDO1_ON_MODE);
+		if (ret < 0)
+			return ret;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int wm831x_gp_ldo_get_status(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int mask = 1 << rdev_get_id(rdev);
+	int ret;
+
+	/* Is the regulator on? */
+	ret = wm831x_reg_read(wm831x, WM831X_LDO_STATUS);
+	if (ret < 0)
+		return ret;
+	if (!(ret & mask))
+		return REGULATOR_STATUS_OFF;
+
+	/* Is it reporting under voltage? */
+	ret = wm831x_reg_read(wm831x, WM831X_LDO_UV_STATUS);
+	if (ret & mask)
+		return REGULATOR_STATUS_ERROR;
+
+	ret = wm831x_gp_ldo_get_mode(rdev);
+	if (ret < 0)
+		return ret;
+	else
+		return regulator_mode_to_status(ret);
+}
+
+static unsigned int wm831x_gp_ldo_get_optimum_mode(struct regulator_dev *rdev,
+						   int input_uV,
+						   int output_uV, int load_uA)
+{
+	if (load_uA < 20000)
+		return REGULATOR_MODE_STANDBY;
+	if (load_uA < 50000)
+		return REGULATOR_MODE_IDLE;
+	return REGULATOR_MODE_NORMAL;
+}
+
+
+static struct regulator_ops wm831x_gp_ldo_ops = {
+	.list_voltage = wm831x_gp_ldo_list_voltage,
+	.get_voltage = wm831x_gp_ldo_get_voltage,
+	.set_voltage = wm831x_gp_ldo_set_voltage,
+	.set_suspend_voltage = wm831x_gp_ldo_set_suspend_voltage,
+	.get_mode = wm831x_gp_ldo_get_mode,
+	.set_mode = wm831x_gp_ldo_set_mode,
+	.get_status = wm831x_gp_ldo_get_status,
+	.get_optimum_mode = wm831x_gp_ldo_get_optimum_mode,
+
+	.is_enabled = wm831x_ldo_is_enabled,
+	.enable = wm831x_ldo_enable,
+	.disable = wm831x_ldo_disable,
+};
+
+static __devinit int wm831x_gp_ldo_probe(struct platform_device *pdev)
+{
+	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
+	struct wm831x_pdata *pdata = wm831x->dev->platform_data;
+	int id = pdev->id % ARRAY_SIZE(pdata->ldo);
+	struct wm831x_ldo *ldo;
+	struct resource *res;
+	int ret, irq;
+
+	dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);
+
+	if (pdata == NULL || pdata->ldo[id] == NULL)
+		return -ENODEV;
+
+	ldo = kzalloc(sizeof(struct wm831x_ldo), GFP_KERNEL);
+	if (ldo == NULL) {
+		dev_err(&pdev->dev, "Unable to allocate private data\n");
+		return -ENOMEM;
+	}
+
+	ldo->wm831x = wm831x;
+
+	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (res == NULL) {
+		dev_err(&pdev->dev, "No I/O resource\n");
+		ret = -EINVAL;
+		goto err;
+	}
+	ldo->base = res->start;
+
+	snprintf(ldo->name, sizeof(ldo->name), "LDO%d", id + 1);
+	ldo->desc.name = ldo->name;
+	ldo->desc.id = id;
+	ldo->desc.type = REGULATOR_VOLTAGE;
+	ldo->desc.n_voltages = WM831X_GP_LDO_MAX_SELECTOR + 1;
+	ldo->desc.ops = &wm831x_gp_ldo_ops;
+	ldo->desc.owner = THIS_MODULE;
+
+	ldo->regulator = regulator_register(&ldo->desc, &pdev->dev,
+					     pdata->ldo[id], ldo);
+	if (IS_ERR(ldo->regulator)) {
+		ret = PTR_ERR(ldo->regulator);
+		dev_err(wm831x->dev, "Failed to register LDO%d: %d\n",
+			id + 1, ret);
+		goto err;
+	}
+
+	irq = platform_get_irq_byname(pdev, "UV");
+	ret = wm831x_request_irq(wm831x, irq, wm831x_ldo_uv_irq,
+				 IRQF_TRIGGER_RISING, ldo->name,
+				 ldo);
+	if (ret != 0) {
+		dev_err(&pdev->dev, "Failed to request UV IRQ %d: %d\n",
+			irq, ret);
+		goto err_regulator;
+	}
+
+	platform_set_drvdata(pdev, ldo);
+
+	return 0;
+
+err_regulator:
+	regulator_unregister(ldo->regulator);
+err:
+	kfree(ldo);
+	return ret;
+}
+
+static __devexit int wm831x_gp_ldo_remove(struct platform_device *pdev)
+{
+	struct wm831x_ldo *ldo = platform_get_drvdata(pdev);
+	struct wm831x *wm831x = ldo->wm831x;
+
+	wm831x_free_irq(wm831x, platform_get_irq_byname(pdev, "UV"), ldo);
+	regulator_unregister(ldo->regulator);
+	kfree(ldo);
+
+	return 0;
+}
+
+static struct platform_driver wm831x_gp_ldo_driver = {
+	.probe = wm831x_gp_ldo_probe,
+	.remove = __devexit_p(wm831x_gp_ldo_remove),
+	.driver		= {
+		.name	= "wm831x-ldo",
+	},
+};
+
+/*
+ * Analogue LDOs
+ */
+
+
+#define WM831X_ALDO_SELECTOR_LOW 0xc
+#define WM831X_ALDO_MAX_SELECTOR 0x1f
+
+static int wm831x_aldo_list_voltage(struct regulator_dev *rdev,
+				      unsigned int selector)
+{
+	/* 1-1.6V in 50mV steps */
+	if (selector <= WM831X_ALDO_SELECTOR_LOW)
+		return 1000000 + (selector * 50000);
+	/* 1.7-3.5V in 50mV steps */
+	if (selector <= WM831X_ALDO_MAX_SELECTOR)
+		return 1600000 + ((selector - WM831X_ALDO_SELECTOR_LOW)
+				  * 100000);
+	return -EINVAL;
+}
+
+static int wm831x_aldo_set_voltage_int(struct regulator_dev *rdev, int reg,
+					 int min_uV, int max_uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int vsel, ret;
+
+	if (min_uV < 1000000)
+		vsel = 0;
+	else if (min_uV < 1700000)
+		vsel = ((min_uV - 1000000) / 50000);
+	else
+		vsel = ((min_uV - 1700000) / 100000)
+			+ WM831X_ALDO_SELECTOR_LOW + 1;
+
+	ret = wm831x_aldo_list_voltage(rdev, vsel);
+	if (ret < 0)
+		return ret;
+	if (ret < min_uV || ret > max_uV)
+		return -EINVAL;
+
+	return wm831x_set_bits(wm831x, reg, WM831X_LDO7_ON_VSEL_MASK, vsel);
+}
+
+static int wm831x_aldo_set_voltage(struct regulator_dev *rdev,
+				     int min_uV, int max_uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	int reg = ldo->base + WM831X_LDO_ON_CONTROL;
+
+	return wm831x_aldo_set_voltage_int(rdev, reg, min_uV, max_uV);
+}
+
+static int wm831x_aldo_set_suspend_voltage(struct regulator_dev *rdev,
+					     int uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	int reg = ldo->base + WM831X_LDO_SLEEP_CONTROL;
+
+	return wm831x_aldo_set_voltage_int(rdev, reg, uV, uV);
+}
+
+static int wm831x_aldo_get_voltage(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int reg = ldo->base + WM831X_LDO_ON_CONTROL;
+	int ret;
+
+	ret = wm831x_reg_read(wm831x, reg);
+	if (ret < 0)
+		return ret;
+
+	ret &= WM831X_LDO7_ON_VSEL_MASK;
+
+	return wm831x_aldo_list_voltage(rdev, ret);
+}
+
+static unsigned int wm831x_aldo_get_mode(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int on_reg = ldo->base + WM831X_LDO_ON_CONTROL;
+	unsigned int ret;
+
+	ret = wm831x_reg_read(wm831x, on_reg);
+	if (ret < 0)
+		return 0;
+
+	if (ret & WM831X_LDO7_ON_MODE)
+		return REGULATOR_MODE_IDLE;
+	else
+		return REGULATOR_MODE_NORMAL;
+}
+
+static int wm831x_aldo_set_mode(struct regulator_dev *rdev,
+				  unsigned int mode)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int ctrl_reg = ldo->base + WM831X_LDO_CONTROL;
+	int on_reg = ldo->base + WM831X_LDO_ON_CONTROL;
+	int ret;
+
+
+	switch (mode) {
+	case REGULATOR_MODE_NORMAL:
+		ret = wm831x_set_bits(wm831x, on_reg,
+				      WM831X_LDO7_ON_MODE, 0);
+		if (ret < 0)
+			return ret;
+		break;
+
+	case REGULATOR_MODE_IDLE:
+		ret = wm831x_set_bits(wm831x, ctrl_reg,
+				      WM831X_LDO7_ON_MODE,
+				      WM831X_LDO7_ON_MODE);
+		if (ret < 0)
+			return ret;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int wm831x_aldo_get_status(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int mask = 1 << rdev_get_id(rdev);
+	int ret;
+
+	/* Is the regulator on? */
+	ret = wm831x_reg_read(wm831x, WM831X_LDO_STATUS);
+	if (ret < 0)
+		return ret;
+	if (!(ret & mask))
+		return REGULATOR_STATUS_OFF;
+
+	/* Is it reporting under voltage? */
+	ret = wm831x_reg_read(wm831x, WM831X_LDO_UV_STATUS);
+	if (ret & mask)
+		return REGULATOR_STATUS_ERROR;
+
+	ret = wm831x_aldo_get_mode(rdev);
+	if (ret < 0)
+		return ret;
+	else
+		return regulator_mode_to_status(ret);
+}
+
+static struct regulator_ops wm831x_aldo_ops = {
+	.list_voltage = wm831x_aldo_list_voltage,
+	.get_voltage = wm831x_aldo_get_voltage,
+	.set_voltage = wm831x_aldo_set_voltage,
+	.set_suspend_voltage = wm831x_aldo_set_suspend_voltage,
+	.get_mode = wm831x_aldo_get_mode,
+	.set_mode = wm831x_aldo_set_mode,
+	.get_status = wm831x_aldo_get_status,
+
+	.is_enabled = wm831x_ldo_is_enabled,
+	.enable = wm831x_ldo_enable,
+	.disable = wm831x_ldo_disable,
+};
+
+static __devinit int wm831x_aldo_probe(struct platform_device *pdev)
+{
+	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
+	struct wm831x_pdata *pdata = wm831x->dev->platform_data;
+	int id = pdev->id % ARRAY_SIZE(pdata->ldo);
+	struct wm831x_ldo *ldo;
+	struct resource *res;
+	int ret, irq;
+
+	dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);
+
+	if (pdata == NULL || pdata->ldo[id] == NULL)
+		return -ENODEV;
+
+	ldo = kzalloc(sizeof(struct wm831x_ldo), GFP_KERNEL);
+	if (ldo == NULL) {
+		dev_err(&pdev->dev, "Unable to allocate private data\n");
+		return -ENOMEM;
+	}
+
+	ldo->wm831x = wm831x;
+
+	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (res == NULL) {
+		dev_err(&pdev->dev, "No I/O resource\n");
+		ret = -EINVAL;
+		goto err;
+	}
+	ldo->base = res->start;
+
+	snprintf(ldo->name, sizeof(ldo->name), "LDO%d", id + 1);
+	ldo->desc.name = ldo->name;
+	ldo->desc.id = id;
+	ldo->desc.type = REGULATOR_VOLTAGE;
+	ldo->desc.n_voltages = WM831X_ALDO_MAX_SELECTOR + 1;
+	ldo->desc.ops = &wm831x_aldo_ops;
+	ldo->desc.owner = THIS_MODULE;
+
+	ldo->regulator = regulator_register(&ldo->desc, &pdev->dev,
+					     pdata->ldo[id], ldo);
+	if (IS_ERR(ldo->regulator)) {
+		ret = PTR_ERR(ldo->regulator);
+		dev_err(wm831x->dev, "Failed to register LDO%d: %d\n",
+			id + 1, ret);
+		goto err;
+	}
+
+	irq = platform_get_irq_byname(pdev, "UV");
+	ret = wm831x_request_irq(wm831x, irq, wm831x_ldo_uv_irq,
+				 IRQF_TRIGGER_RISING, ldo->name,
+				 ldo);
+	if (ret != 0) {
+		dev_err(&pdev->dev, "Failed to request UV IRQ %d: %d\n",
+			irq, ret);
+		goto err_regulator;
+	}
+
+	platform_set_drvdata(pdev, ldo);
+
+	return 0;
+
+err_regulator:
+	regulator_unregister(ldo->regulator);
+err:
+	kfree(ldo);
+	return ret;
+}
+
+static __devexit int wm831x_aldo_remove(struct platform_device *pdev)
+{
+	struct wm831x_ldo *ldo = platform_get_drvdata(pdev);
+	struct wm831x *wm831x = ldo->wm831x;
+
+	wm831x_free_irq(wm831x, platform_get_irq_byname(pdev, "UV"), ldo);
+	regulator_unregister(ldo->regulator);
+	kfree(ldo);
+
+	return 0;
+}
+
+static struct platform_driver wm831x_aldo_driver = {
+	.probe = wm831x_aldo_probe,
+	.remove = __devexit_p(wm831x_aldo_remove),
+	.driver		= {
+		.name	= "wm831x-aldo",
+	},
+};
+
+/*
+ * Alive LDO
+ */
+
+#define WM831X_ALIVE_LDO_MAX_SELECTOR 0xf
+
+static int wm831x_alive_ldo_list_voltage(struct regulator_dev *rdev,
+				      unsigned int selector)
+{
+	/* 0.8-1.55V in 50mV steps */
+	if (selector <= WM831X_ALIVE_LDO_MAX_SELECTOR)
+		return 800000 + (selector * 50000);
+	return -EINVAL;
+}
+
+static int wm831x_alive_ldo_set_voltage_int(struct regulator_dev *rdev,
+					    int reg,
+					    int min_uV, int max_uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int vsel, ret;
+
+	vsel = (min_uV - 800000) / 50000;
+
+	ret = wm831x_alive_ldo_list_voltage(rdev, vsel);
+	if (ret < 0)
+		return ret;
+	if (ret < min_uV || ret > max_uV)
+		return -EINVAL;
+
+	return wm831x_set_bits(wm831x, reg, WM831X_LDO11_ON_VSEL_MASK, vsel);
+}
+
+static int wm831x_alive_ldo_set_voltage(struct regulator_dev *rdev,
+				     int min_uV, int max_uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	int reg = ldo->base + WM831X_ALIVE_LDO_ON_CONTROL;
+
+	return wm831x_alive_ldo_set_voltage_int(rdev, reg, min_uV, max_uV);
+}
+
+static int wm831x_alive_ldo_set_suspend_voltage(struct regulator_dev *rdev,
+					     int uV)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	int reg = ldo->base + WM831X_ALIVE_LDO_SLEEP_CONTROL;
+
+	return wm831x_alive_ldo_set_voltage_int(rdev, reg, uV, uV);
+}
+
+static int wm831x_alive_ldo_get_voltage(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int reg = ldo->base + WM831X_ALIVE_LDO_ON_CONTROL;
+	int ret;
+
+	ret = wm831x_reg_read(wm831x, reg);
+	if (ret < 0)
+		return ret;
+
+	ret &= WM831X_LDO11_ON_VSEL_MASK;
+
+	return wm831x_alive_ldo_list_voltage(rdev, ret);
+}
+
+static int wm831x_alive_ldo_get_status(struct regulator_dev *rdev)
+{
+	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
+	struct wm831x *wm831x = ldo->wm831x;
+	int mask = 1 << rdev_get_id(rdev);
+	int ret;
+
+	/* Is the regulator on? */
+	ret = wm831x_reg_read(wm831x, WM831X_LDO_STATUS);
+	if (ret < 0)
+		return ret;
+	if (ret & mask)
+		return REGULATOR_STATUS_ON;
+	else
+		return REGULATOR_STATUS_OFF;
+}
+
+static struct regulator_ops wm831x_alive_ldo_ops = {
+	.list_voltage = wm831x_alive_ldo_list_voltage,
+	.get_voltage = wm831x_alive_ldo_get_voltage,
+	.set_voltage = wm831x_alive_ldo_set_voltage,
+	.set_suspend_voltage = wm831x_alive_ldo_set_suspend_voltage,
+	.get_status = wm831x_alive_ldo_get_status,
+
+	.is_enabled = wm831x_ldo_is_enabled,
+	.enable = wm831x_ldo_enable,
+	.disable = wm831x_ldo_disable,
+};
+
+static __devinit int wm831x_alive_ldo_probe(struct platform_device *pdev)
+{
+	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
+	struct wm831x_pdata *pdata = wm831x->dev->platform_data;
+	int id = pdev->id % ARRAY_SIZE(pdata->ldo);
+	struct wm831x_ldo *ldo;
+	struct resource *res;
+	int ret;
+
+	dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);
+
+	if (pdata == NULL || pdata->ldo[id] == NULL)
+		return -ENODEV;
+
+	ldo = kzalloc(sizeof(struct wm831x_ldo), GFP_KERNEL);
+	if (ldo == NULL) {
+		dev_err(&pdev->dev, "Unable to allocate private data\n");
+		return -ENOMEM;
+	}
+
+	ldo->wm831x = wm831x;
+
+	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (res == NULL) {
+		dev_err(&pdev->dev, "No I/O resource\n");
+		ret = -EINVAL;
+		goto err;
+	}
+	ldo->base = res->start;
+
+	snprintf(ldo->name, sizeof(ldo->name), "LDO%d", id + 1);
+	ldo->desc.name = ldo->name;
+	ldo->desc.id = id;
+	ldo->desc.type = REGULATOR_VOLTAGE;
+	ldo->desc.n_voltages = WM831X_ALIVE_LDO_MAX_SELECTOR + 1;
+	ldo->desc.ops = &wm831x_alive_ldo_ops;
+	ldo->desc.owner = THIS_MODULE;
+
+	ldo->regulator = regulator_register(&ldo->desc, &pdev->dev,
+					     pdata->ldo[id], ldo);
+	if (IS_ERR(ldo->regulator)) {
+		ret = PTR_ERR(ldo->regulator);
+		dev_err(wm831x->dev, "Failed to register LDO%d: %d\n",
+			id + 1, ret);
+		goto err;
+	}
+
+	platform_set_drvdata(pdev, ldo);
+
+	return 0;
+
+err:
+	kfree(ldo);
+	return ret;
+}
+
+static __devexit int wm831x_alive_ldo_remove(struct platform_device *pdev)
+{
+	struct wm831x_ldo *ldo = platform_get_drvdata(pdev);
+
+	regulator_unregister(ldo->regulator);
+	kfree(ldo);
+
+	return 0;
+}
+
+static struct platform_driver wm831x_alive_ldo_driver = {
+	.probe = wm831x_alive_ldo_probe,
+	.remove = __devexit_p(wm831x_alive_ldo_remove),
+	.driver		= {
+		.name	= "wm831x-alive-ldo",
+	},
+};
+
+static int __init wm831x_ldo_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&wm831x_gp_ldo_driver);
+	if (ret != 0)
+		pr_err("Failed to register WM831x GP LDO driver: %d\n", ret);
+
+	ret = platform_driver_register(&wm831x_aldo_driver);
+	if (ret != 0)
+		pr_err("Failed to register WM831x ALDO driver: %d\n", ret);
+
+	ret = platform_driver_register(&wm831x_alive_ldo_driver);
+	if (ret != 0)
+		pr_err("Failed to register WM831x alive LDO driver: %d\n",
+		       ret);
+
+	return 0;
+}
+subsys_initcall(wm831x_ldo_init);
+
+static void __exit wm831x_ldo_exit(void)
+{
+	platform_driver_unregister(&wm831x_alive_ldo_driver);
+	platform_driver_unregister(&wm831x_aldo_driver);
+	platform_driver_unregister(&wm831x_gp_ldo_driver);
+}
+module_exit(wm831x_ldo_exit);
+
+/* Module information */
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("WM831x LDO driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm831x-ldo");
+MODULE_ALIAS("platform:wm831x-aldo");
+MODULE_ALIAS("platform:wm831x-aliveldo");