regulator: qcom-rpm: Regulator driver for the Qualcomm RPM

Driver for regulators exposed by the Resource Power Manager (RPM) found
in Qualcomm 8660, 8960 and 8064 based devices.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 798 insertions, 0 deletions

diff --git a/drivers/regulator/qcom_rpm-regulator.c b/drivers/regulator/qcom_rpm-regulator.c
new file mode 100644
index 000000000000..8f283098788a
--- /dev/null
+++ b/drivers/regulator/qcom_rpm-regulator.c
@@ -0,0 +1,798 @@
+/*
+ * Copyright (c) 2014, Sony Mobile Communications AB.
+ * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/mfd/qcom_rpm.h>
+
+#include <dt-bindings/mfd/qcom-rpm.h>
+
+#define MAX_REQUEST_LEN 2
+
+struct request_member {
+	int		word;
+	unsigned int	mask;
+	int		shift;
+};
+
+struct rpm_reg_parts {
+	struct request_member mV;		/* used if voltage is in mV */
+	struct request_member uV;		/* used if voltage is in uV */
+	struct request_member ip;		/* peak current in mA */
+	struct request_member pd;		/* pull down enable */
+	struct request_member ia;		/* average current in mA */
+	struct request_member fm;		/* force mode */
+	struct request_member pm;		/* power mode */
+	struct request_member pc;		/* pin control */
+	struct request_member pf;		/* pin function */
+	struct request_member enable_state;	/* NCP and switch */
+	struct request_member comp_mode;	/* NCP */
+	struct request_member freq;		/* frequency: NCP and SMPS */
+	struct request_member freq_clk_src;	/* clock source: SMPS */
+	struct request_member hpm;		/* switch: control OCP and SS */
+	int request_len;
+};
+
+#define FORCE_MODE_IS_2_BITS(reg) \
+	((vreg->parts->fm.mask >> vreg->parts->fm.shift) == 3)
+
+struct qcom_rpm_reg {
+	struct qcom_rpm *rpm;
+
+	struct mutex lock;
+	struct device *dev;
+	struct regulator_desc desc;
+	const struct rpm_reg_parts *parts;
+
+	int resource;
+	u32 val[MAX_REQUEST_LEN];
+
+	int uV;
+	int is_enabled;
+
+	bool supports_force_mode_auto;
+	bool supports_force_mode_bypass;
+};
+
+static const struct rpm_reg_parts rpm8660_ldo_parts = {
+	.request_len    = 2,
+	.mV             = { 0, 0x00000FFF,  0 },
+	.ip             = { 0, 0x00FFF000, 12 },
+	.fm             = { 0, 0x03000000, 24 },
+	.pc             = { 0, 0x3C000000, 26 },
+	.pf             = { 0, 0xC0000000, 30 },
+	.pd             = { 1, 0x00000001,  0 },
+	.ia             = { 1, 0x00001FFE,  1 },
+};
+
+static const struct rpm_reg_parts rpm8660_smps_parts = {
+	.request_len    = 2,
+	.mV             = { 0, 0x00000FFF,  0 },
+	.ip             = { 0, 0x00FFF000, 12 },
+	.fm             = { 0, 0x03000000, 24 },
+	.pc             = { 0, 0x3C000000, 26 },
+	.pf             = { 0, 0xC0000000, 30 },
+	.pd             = { 1, 0x00000001,  0 },
+	.ia             = { 1, 0x00001FFE,  1 },
+	.freq           = { 1, 0x001FE000, 13 },
+	.freq_clk_src   = { 1, 0x00600000, 21 },
+};
+
+static const struct rpm_reg_parts rpm8660_switch_parts = {
+	.request_len    = 1,
+	.enable_state   = { 0, 0x00000001,  0 },
+	.pd             = { 0, 0x00000002,  1 },
+	.pc             = { 0, 0x0000003C,  2 },
+	.pf             = { 0, 0x000000C0,  6 },
+	.hpm            = { 0, 0x00000300,  8 },
+};
+
+static const struct rpm_reg_parts rpm8660_ncp_parts = {
+	.request_len    = 1,
+	.mV             = { 0, 0x00000FFF,  0 },
+	.enable_state   = { 0, 0x00001000, 12 },
+	.comp_mode      = { 0, 0x00002000, 13 },
+	.freq           = { 0, 0x003FC000, 14 },
+};
+
+static const struct rpm_reg_parts rpm8960_ldo_parts = {
+	.request_len    = 2,
+	.uV             = { 0, 0x007FFFFF,  0 },
+	.pd             = { 0, 0x00800000, 23 },
+	.pc             = { 0, 0x0F000000, 24 },
+	.pf             = { 0, 0xF0000000, 28 },
+	.ip             = { 1, 0x000003FF,  0 },
+	.ia             = { 1, 0x000FFC00, 10 },
+	.fm             = { 1, 0x00700000, 20 },
+};
+
+static const struct rpm_reg_parts rpm8960_smps_parts = {
+	.request_len    = 2,
+	.uV             = { 0, 0x007FFFFF,  0 },
+	.pd             = { 0, 0x00800000, 23 },
+	.pc             = { 0, 0x0F000000, 24 },
+	.pf             = { 0, 0xF0000000, 28 },
+	.ip             = { 1, 0x000003FF,  0 },
+	.ia             = { 1, 0x000FFC00, 10 },
+	.fm             = { 1, 0x00700000, 20 },
+	.pm             = { 1, 0x00800000, 23 },
+	.freq           = { 1, 0x1F000000, 24 },
+	.freq_clk_src   = { 1, 0x60000000, 29 },
+};
+
+static const struct rpm_reg_parts rpm8960_switch_parts = {
+	.request_len    = 1,
+	.enable_state   = { 0, 0x00000001,  0 },
+	.pd             = { 0, 0x00000002,  1 },
+	.pc             = { 0, 0x0000003C,  2 },
+	.pf             = { 0, 0x000003C0,  6 },
+	.hpm            = { 0, 0x00000C00, 10 },
+};
+
+static const struct rpm_reg_parts rpm8960_ncp_parts = {
+	.request_len    = 1,
+	.uV             = { 0, 0x007FFFFF,  0 },
+	.enable_state   = { 0, 0x00800000, 23 },
+	.comp_mode      = { 0, 0x01000000, 24 },
+	.freq           = { 0, 0x3E000000, 25 },
+};
+
+/*
+ * Physically available PMIC regulator voltage ranges
+ */
+static const struct regulator_linear_range pldo_ranges[] = {
+	REGULATOR_LINEAR_RANGE( 750000,   0,  59, 12500),
+	REGULATOR_LINEAR_RANGE(1500000,  60, 123, 25000),
+	REGULATOR_LINEAR_RANGE(3100000, 124, 160, 50000),
+};
+
+static const struct regulator_linear_range nldo_ranges[] = {
+	REGULATOR_LINEAR_RANGE( 750000,   0,  63, 12500),
+};
+
+static const struct regulator_linear_range nldo1200_ranges[] = {
+	REGULATOR_LINEAR_RANGE( 375000,   0,  59,  6250),
+	REGULATOR_LINEAR_RANGE( 750000,  60, 123, 12500),
+};
+
+static const struct regulator_linear_range smps_ranges[] = {
+	REGULATOR_LINEAR_RANGE( 375000,   0,  29, 12500),
+	REGULATOR_LINEAR_RANGE( 750000,  30,  89, 12500),
+	REGULATOR_LINEAR_RANGE(1500000,  90, 153, 25000),
+};
+
+static const struct regulator_linear_range ftsmps_ranges[] = {
+	REGULATOR_LINEAR_RANGE( 350000,   0,   6, 50000),
+	REGULATOR_LINEAR_RANGE( 700000,   7,  63, 12500),
+	REGULATOR_LINEAR_RANGE(1500000,  64, 100, 50000),
+};
+
+static const struct regulator_linear_range ncp_ranges[] = {
+	REGULATOR_LINEAR_RANGE(1500000,   0,  31, 50000),
+};
+
+static int rpm_reg_write(struct qcom_rpm_reg *vreg,
+			 const struct request_member *req,
+			 const int value)
+{
+	if (WARN_ON((value << req->shift) & ~req->mask))
+		return -EINVAL;
+
+	vreg->val[req->word] &= ~req->mask;
+	vreg->val[req->word] |= value << req->shift;
+
+	return qcom_rpm_write(vreg->rpm,
+			      vreg->resource,
+			      vreg->val,
+			      vreg->parts->request_len);
+}
+
+static int rpm_reg_set_mV_sel(struct regulator_dev *rdev,
+			      unsigned selector)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+	const struct rpm_reg_parts *parts = vreg->parts;
+	const struct request_member *req = &parts->mV;
+	int ret = 0;
+	int uV;
+
+	if (req->mask == 0)
+		return -EINVAL;
+
+	uV = regulator_list_voltage_linear_range(rdev, selector);
+	if (uV < 0)
+		return uV;
+
+	mutex_lock(&vreg->lock);
+	vreg->uV = uV;
+	if (vreg->is_enabled)
+		ret = rpm_reg_write(vreg, req, vreg->uV / 1000);
+	mutex_unlock(&vreg->lock);
+
+	return ret;
+}
+
+static int rpm_reg_set_uV_sel(struct regulator_dev *rdev,
+			      unsigned selector)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+	const struct rpm_reg_parts *parts = vreg->parts;
+	const struct request_member *req = &parts->uV;
+	int ret = 0;
+	int uV;
+
+	if (req->mask == 0)
+		return -EINVAL;
+
+	uV = regulator_list_voltage_linear_range(rdev, selector);
+	if (uV < 0)
+		return uV;
+
+	mutex_lock(&vreg->lock);
+	vreg->uV = uV;
+	if (vreg->is_enabled)
+		ret = rpm_reg_write(vreg, req, vreg->uV);
+	mutex_unlock(&vreg->lock);
+
+	return ret;
+}
+
+static int rpm_reg_get_voltage(struct regulator_dev *rdev)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+
+	return vreg->uV;
+}
+
+static int rpm_reg_mV_enable(struct regulator_dev *rdev)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+	const struct rpm_reg_parts *parts = vreg->parts;
+	const struct request_member *req = &parts->mV;
+	int ret;
+
+	if (req->mask == 0)
+		return -EINVAL;
+
+	mutex_lock(&vreg->lock);
+	ret = rpm_reg_write(vreg, req, vreg->uV / 1000);
+	if (!ret)
+		vreg->is_enabled = 1;
+	mutex_unlock(&vreg->lock);
+
+	return ret;
+}
+
+static int rpm_reg_uV_enable(struct regulator_dev *rdev)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+	const struct rpm_reg_parts *parts = vreg->parts;
+	const struct request_member *req = &parts->uV;
+	int ret;
+
+	if (req->mask == 0)
+		return -EINVAL;
+
+	mutex_lock(&vreg->lock);
+	ret = rpm_reg_write(vreg, req, vreg->uV);
+	if (!ret)
+		vreg->is_enabled = 1;
+	mutex_unlock(&vreg->lock);
+
+	return ret;
+}
+
+static int rpm_reg_switch_enable(struct regulator_dev *rdev)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+	const struct rpm_reg_parts *parts = vreg->parts;
+	const struct request_member *req = &parts->enable_state;
+	int ret;
+
+	if (req->mask == 0)
+		return -EINVAL;
+
+	mutex_lock(&vreg->lock);
+	ret = rpm_reg_write(vreg, req, 1);
+	if (!ret)
+		vreg->is_enabled = 1;
+	mutex_unlock(&vreg->lock);
+
+	return ret;
+}
+
+static int rpm_reg_mV_disable(struct regulator_dev *rdev)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+	const struct rpm_reg_parts *parts = vreg->parts;
+	const struct request_member *req = &parts->mV;
+	int ret;
+
+	if (req->mask == 0)
+		return -EINVAL;
+
+	mutex_lock(&vreg->lock);
+	ret = rpm_reg_write(vreg, req, 0);
+	if (!ret)
+		vreg->is_enabled = 0;
+	mutex_unlock(&vreg->lock);
+
+	return ret;
+}
+
+static int rpm_reg_uV_disable(struct regulator_dev *rdev)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+	const struct rpm_reg_parts *parts = vreg->parts;
+	const struct request_member *req = &parts->uV;
+	int ret;
+
+	if (req->mask == 0)
+		return -EINVAL;
+
+	mutex_lock(&vreg->lock);
+	ret = rpm_reg_write(vreg, req, 0);
+	if (!ret)
+		vreg->is_enabled = 0;
+	mutex_unlock(&vreg->lock);
+
+	return ret;
+}
+
+static int rpm_reg_switch_disable(struct regulator_dev *rdev)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+	const struct rpm_reg_parts *parts = vreg->parts;
+	const struct request_member *req = &parts->enable_state;
+	int ret;
+
+	if (req->mask == 0)
+		return -EINVAL;
+
+	mutex_lock(&vreg->lock);
+	ret = rpm_reg_write(vreg, req, 0);
+	if (!ret)
+		vreg->is_enabled = 0;
+	mutex_unlock(&vreg->lock);
+
+	return ret;
+}
+
+static int rpm_reg_is_enabled(struct regulator_dev *rdev)
+{
+	struct qcom_rpm_reg *vreg = rdev_get_drvdata(rdev);
+
+	return vreg->is_enabled;
+}
+
+static struct regulator_ops uV_ops = {
+	.list_voltage = regulator_list_voltage_linear_range,
+
+	.set_voltage_sel = rpm_reg_set_uV_sel,
+	.get_voltage = rpm_reg_get_voltage,
+
+	.enable = rpm_reg_uV_enable,
+	.disable = rpm_reg_uV_disable,
+	.is_enabled = rpm_reg_is_enabled,
+};
+
+static struct regulator_ops mV_ops = {
+	.list_voltage = regulator_list_voltage_linear_range,
+
+	.set_voltage_sel = rpm_reg_set_mV_sel,
+	.get_voltage = rpm_reg_get_voltage,
+
+	.enable = rpm_reg_mV_enable,
+	.disable = rpm_reg_mV_disable,
+	.is_enabled = rpm_reg_is_enabled,
+};
+
+static struct regulator_ops switch_ops = {
+	.enable = rpm_reg_switch_enable,
+	.disable = rpm_reg_switch_disable,
+	.is_enabled = rpm_reg_is_enabled,
+};
+
+/*
+ * PM8058 regulators
+ */
+static const struct qcom_rpm_reg pm8058_pldo = {
+	.desc.linear_ranges = pldo_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(pldo_ranges),
+	.desc.n_voltages = 161,
+	.desc.ops = &mV_ops,
+	.parts = &rpm8660_ldo_parts,
+	.supports_force_mode_auto = false,
+	.supports_force_mode_bypass = false,
+};
+
+static const struct qcom_rpm_reg pm8058_nldo = {
+	.desc.linear_ranges = nldo_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(nldo_ranges),
+	.desc.n_voltages = 64,
+	.desc.ops = &mV_ops,
+	.parts = &rpm8660_ldo_parts,
+	.supports_force_mode_auto = false,
+	.supports_force_mode_bypass = false,
+};
+
+static const struct qcom_rpm_reg pm8058_smps = {
+	.desc.linear_ranges = smps_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(smps_ranges),
+	.desc.n_voltages = 154,
+	.desc.ops = &mV_ops,
+	.parts = &rpm8660_smps_parts,
+	.supports_force_mode_auto = false,
+	.supports_force_mode_bypass = false,
+};
+
+static const struct qcom_rpm_reg pm8058_ncp = {
+	.desc.linear_ranges = ncp_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(ncp_ranges),
+	.desc.n_voltages = 32,
+	.desc.ops = &mV_ops,
+	.parts = &rpm8660_ncp_parts,
+};
+
+static const struct qcom_rpm_reg pm8058_switch = {
+	.desc.ops = &switch_ops,
+	.parts = &rpm8660_switch_parts,
+};
+
+/*
+ * PM8901 regulators
+ */
+static const struct qcom_rpm_reg pm8901_pldo = {
+	.desc.linear_ranges = pldo_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(pldo_ranges),
+	.desc.n_voltages = 161,
+	.desc.ops = &mV_ops,
+	.parts = &rpm8660_ldo_parts,
+	.supports_force_mode_auto = false,
+	.supports_force_mode_bypass = true,
+};
+
+static const struct qcom_rpm_reg pm8901_nldo = {
+	.desc.linear_ranges = nldo_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(nldo_ranges),
+	.desc.n_voltages = 64,
+	.desc.ops = &mV_ops,
+	.parts = &rpm8660_ldo_parts,
+	.supports_force_mode_auto = false,
+	.supports_force_mode_bypass = true,
+};
+
+static const struct qcom_rpm_reg pm8901_ftsmps = {
+	.desc.linear_ranges = ftsmps_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(ftsmps_ranges),
+	.desc.n_voltages = 101,
+	.desc.ops = &mV_ops,
+	.parts = &rpm8660_smps_parts,
+	.supports_force_mode_auto = true,
+	.supports_force_mode_bypass = false,
+};
+
+static const struct qcom_rpm_reg pm8901_switch = {
+	.desc.ops = &switch_ops,
+	.parts = &rpm8660_switch_parts,
+};
+
+/*
+ * PM8921 regulators
+ */
+static const struct qcom_rpm_reg pm8921_pldo = {
+	.desc.linear_ranges = pldo_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(pldo_ranges),
+	.desc.n_voltages = 161,
+	.desc.ops = &uV_ops,
+	.parts = &rpm8960_ldo_parts,
+	.supports_force_mode_auto = false,
+	.supports_force_mode_bypass = true,
+};
+
+static const struct qcom_rpm_reg pm8921_nldo = {
+	.desc.linear_ranges = nldo_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(nldo_ranges),
+	.desc.n_voltages = 64,
+	.desc.ops = &uV_ops,
+	.parts = &rpm8960_ldo_parts,
+	.supports_force_mode_auto = false,
+	.supports_force_mode_bypass = true,
+};
+
+static const struct qcom_rpm_reg pm8921_nldo1200 = {
+	.desc.linear_ranges = nldo1200_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(nldo1200_ranges),
+	.desc.n_voltages = 124,
+	.desc.ops = &uV_ops,
+	.parts = &rpm8960_ldo_parts,
+	.supports_force_mode_auto = false,
+	.supports_force_mode_bypass = true,
+};
+
+static const struct qcom_rpm_reg pm8921_smps = {
+	.desc.linear_ranges = smps_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(smps_ranges),
+	.desc.n_voltages = 154,
+	.desc.ops = &uV_ops,
+	.parts = &rpm8960_smps_parts,
+	.supports_force_mode_auto = true,
+	.supports_force_mode_bypass = false,
+};
+
+static const struct qcom_rpm_reg pm8921_ftsmps = {
+	.desc.linear_ranges = ftsmps_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(ftsmps_ranges),
+	.desc.n_voltages = 101,
+	.desc.ops = &uV_ops,
+	.parts = &rpm8960_smps_parts,
+	.supports_force_mode_auto = true,
+	.supports_force_mode_bypass = false,
+};
+
+static const struct qcom_rpm_reg pm8921_ncp = {
+	.desc.linear_ranges = ncp_ranges,
+	.desc.n_linear_ranges = ARRAY_SIZE(ncp_ranges),
+	.desc.n_voltages = 32,
+	.desc.ops = &uV_ops,
+	.parts = &rpm8960_ncp_parts,
+};
+
+static const struct qcom_rpm_reg pm8921_switch = {
+	.desc.ops = &switch_ops,
+	.parts = &rpm8960_switch_parts,
+};
+
+static const struct of_device_id rpm_of_match[] = {
+	{ .compatible = "qcom,rpm-pm8058-pldo",     .data = &pm8058_pldo },
+	{ .compatible = "qcom,rpm-pm8058-nldo",     .data = &pm8058_nldo },
+	{ .compatible = "qcom,rpm-pm8058-smps",     .data = &pm8058_smps },
+	{ .compatible = "qcom,rpm-pm8058-ncp",      .data = &pm8058_ncp },
+	{ .compatible = "qcom,rpm-pm8058-switch",   .data = &pm8058_switch },
+
+	{ .compatible = "qcom,rpm-pm8901-pldo",     .data = &pm8901_pldo },
+	{ .compatible = "qcom,rpm-pm8901-nldo",     .data = &pm8901_nldo },
+	{ .compatible = "qcom,rpm-pm8901-ftsmps",   .data = &pm8901_ftsmps },
+	{ .compatible = "qcom,rpm-pm8901-switch",   .data = &pm8901_switch },
+
+	{ .compatible = "qcom,rpm-pm8921-pldo",     .data = &pm8921_pldo },
+	{ .compatible = "qcom,rpm-pm8921-nldo",     .data = &pm8921_nldo },
+	{ .compatible = "qcom,rpm-pm8921-nldo1200", .data = &pm8921_nldo1200 },
+	{ .compatible = "qcom,rpm-pm8921-smps",     .data = &pm8921_smps },
+	{ .compatible = "qcom,rpm-pm8921-ftsmps",   .data = &pm8921_ftsmps },
+	{ .compatible = "qcom,rpm-pm8921-ncp",      .data = &pm8921_ncp },
+	{ .compatible = "qcom,rpm-pm8921-switch",   .data = &pm8921_switch },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, rpm_of_match);
+
+static int rpm_reg_set(struct qcom_rpm_reg *vreg,
+		       const struct request_member *req,
+		       const int value)
+{
+	if (req->mask == 0 || (value << req->shift) & ~req->mask)
+		return -EINVAL;
+
+	vreg->val[req->word] &= ~req->mask;
+	vreg->val[req->word] |= value << req->shift;
+
+	return 0;
+}
+
+static int rpm_reg_of_parse_freq(struct device *dev, struct qcom_rpm_reg *vreg)
+{
+	static const int freq_table[] = {
+		19200000, 9600000, 6400000, 4800000, 3840000, 3200000, 2740000,
+		2400000, 2130000, 1920000, 1750000, 1600000, 1480000, 1370000,
+		1280000, 1200000,
+
+	};
+	const char *key;
+	u32 freq;
+	int ret;
+	int i;
+
+	key = "qcom,switch-mode-frequency";
+	ret = of_property_read_u32(dev->of_node, key, &freq);
+	if (ret) {
+		dev_err(dev, "regulator requires %s property\n", key);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(freq_table); i++) {
+		if (freq == freq_table[i]) {
+			rpm_reg_set(vreg, &vreg->parts->freq, i + 1);
+			return 0;
+		}
+	}
+
+	dev_err(dev, "invalid frequency %d\n", freq);
+	return -EINVAL;
+}
+
+static int rpm_reg_probe(struct platform_device *pdev)
+{
+	struct regulator_init_data *initdata;
+	const struct qcom_rpm_reg *template;
+	const struct of_device_id *match;
+	struct regulator_config config = { 0 };
+	struct regulator_dev *rdev;
+	struct qcom_rpm_reg *vreg;
+	const char *key;
+	u32 force_mode;
+	bool pwm;
+	u32 val;
+	int ret;
+
+	match = of_match_device(rpm_of_match, &pdev->dev);
+	template = match->data;
+
+	initdata = of_get_regulator_init_data(&pdev->dev, pdev->dev.of_node);
+	if (!initdata)
+		return -EINVAL;
+
+	vreg = devm_kmalloc(&pdev->dev, sizeof(*vreg), GFP_KERNEL);
+	if (!vreg) {
+		dev_err(&pdev->dev, "failed to allocate vreg\n");
+		return -ENOMEM;
+	}
+	memcpy(vreg, template, sizeof(*vreg));
+	mutex_init(&vreg->lock);
+	vreg->dev = &pdev->dev;
+	vreg->desc.id = -1;
+	vreg->desc.owner = THIS_MODULE;
+	vreg->desc.type = REGULATOR_VOLTAGE;
+	vreg->desc.name = pdev->dev.of_node->name;
+
+	vreg->rpm = dev_get_drvdata(pdev->dev.parent);
+	if (!vreg->rpm) {
+		dev_err(&pdev->dev, "unable to retrieve handle to rpm\n");
+		return -ENODEV;
+	}
+
+	key = "reg";
+	ret = of_property_read_u32(pdev->dev.of_node, key, &val);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to read %s\n", key);
+		return ret;
+	}
+	vreg->resource = val;
+
+	if ((vreg->parts->uV.mask || vreg->parts->mV.mask) &&
+	    (!initdata->constraints.min_uV || !initdata->constraints.max_uV)) {
+		dev_err(&pdev->dev, "no voltage specified for regulator\n");
+		return -EINVAL;
+	}
+
+	key = "bias-pull-down";
+	if (of_property_read_bool(pdev->dev.of_node, key)) {
+		ret = rpm_reg_set(vreg, &vreg->parts->pd, 1);
+		if (ret) {
+			dev_err(&pdev->dev, "%s is invalid", key);
+			return ret;
+		}
+	}
+
+	if (vreg->parts->freq.mask) {
+		ret = rpm_reg_of_parse_freq(&pdev->dev, vreg);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (vreg->parts->pm.mask) {
+		key = "qcom,power-mode-hysteretic";
+		pwm = !of_property_read_bool(pdev->dev.of_node, key);
+
+		ret = rpm_reg_set(vreg, &vreg->parts->pm, pwm);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to set power mode\n");
+			return ret;
+		}
+	}
+
+	if (vreg->parts->fm.mask) {
+		force_mode = -1;
+
+		key = "qcom,force-mode";
+		ret = of_property_read_u32(pdev->dev.of_node, key, &val);
+		if (ret == -EINVAL) {
+			val = QCOM_RPM_FORCE_MODE_NONE;
+		} else if (ret < 0) {
+			dev_err(&pdev->dev, "failed to read %s\n", key);
+			return ret;
+		}
+
+		/*
+		 * If force-mode is encoded as 2 bits then the
+		 * possible register values are:
+		 * NONE, LPM, HPM
+		 * otherwise:
+		 * NONE, LPM, AUTO, HPM, BYPASS
+		 */
+		switch (val) {
+		case QCOM_RPM_FORCE_MODE_NONE:
+			force_mode = 0;
+			break;
+		case QCOM_RPM_FORCE_MODE_LPM:
+			force_mode = 1;
+			break;
+		case QCOM_RPM_FORCE_MODE_HPM:
+			if (FORCE_MODE_IS_2_BITS(vreg))
+				force_mode = 2;
+			else
+				force_mode = 3;
+			break;
+		case QCOM_RPM_FORCE_MODE_AUTO:
+			if (vreg->supports_force_mode_auto)
+				force_mode = 2;
+			break;
+		case QCOM_RPM_FORCE_MODE_BYPASS:
+			if (vreg->supports_force_mode_bypass)
+				force_mode = 4;
+			break;
+		}
+
+		if (force_mode < 0) {
+			dev_err(&pdev->dev, "invalid force mode\n");
+			return -EINVAL;
+		}
+
+		ret = rpm_reg_set(vreg, &vreg->parts->fm, force_mode);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to set force mode\n");
+			return ret;
+		}
+	}
+
+	config.dev = &pdev->dev;
+	config.init_data = initdata;
+	config.driver_data = vreg;
+	config.of_node = pdev->dev.of_node;
+	rdev = devm_regulator_register(&pdev->dev, &vreg->desc, &config);
+	if (IS_ERR(rdev)) {
+		dev_err(&pdev->dev, "can't register regulator\n");
+		return PTR_ERR(rdev);
+	}
+
+	return 0;
+}
+
+static struct platform_driver rpm_reg_driver = {
+	.probe          = rpm_reg_probe,
+	.driver  = {
+		.name  = "qcom_rpm_reg",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(rpm_of_match),
+	},
+};
+
+static int __init rpm_reg_init(void)
+{
+	return platform_driver_register(&rpm_reg_driver);
+}
+subsys_initcall(rpm_reg_init);
+
+static void __exit rpm_reg_exit(void)
+{
+	platform_driver_unregister(&rpm_reg_driver);
+}
+module_exit(rpm_reg_exit)
+
+MODULE_DESCRIPTION("Qualcomm RPM regulator driver");
+MODULE_LICENSE("GPL v2");