regulator: add snapshot of cpr3-regulator and dependent drivers

Add a snapshot of the cpr3-regulator family of drivers as well as
the other drivers that CPR depends upon.

This snapshot is taken as of msm-4.4
commit d24550bbf50f ("Merge "ARM: dts: msm: Add slimbus slave
device for wcn3990 on sdm630"").

Change-Id: Ic7f81d77a8642d8581242d2a7a46c26ac3eb81a4
Signed-off-by: David Collins <collinsd@codeaurora.org>
diff --git a/drivers/regulator/cpr4-apss-regulator.c b/drivers/regulator/cpr4-apss-regulator.c
new file mode 100644
index 0000000..cfc09ba
--- /dev/null
+++ b/drivers/regulator/cpr4-apss-regulator.c
@@ -0,0 +1,1436 @@
+/*
+ * Copyright (c) 2015-2017, 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.
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/bitops.h>
+#include <linux/debugfs.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+
+#include "cpr3-regulator.h"
+
+#define MSM8953_APSS_FUSE_CORNERS	4
+
+/**
+ * struct cpr4_msm8953_apss_fuses - APSS specific fuse data for MSM8953
+ * @ro_sel:		Ring oscillator select fuse parameter value for each
+ *			fuse corner
+ * @init_voltage:	Initial (i.e. open-loop) voltage fuse parameter value
+ *			for each fuse corner (raw, not converted to a voltage)
+ * @target_quot:	CPR target quotient fuse parameter value for each fuse
+ *			corner
+ * @quot_offset:	CPR target quotient offset fuse parameter value for each
+ *			fuse corner (raw, not unpacked) used for target quotient
+ *			interpolation
+ * @speed_bin:		Application processor speed bin fuse parameter value for
+ *			the given chip
+ * @cpr_fusing_rev:	CPR fusing revision fuse parameter value
+ * @boost_cfg:		CPR boost configuration fuse parameter value
+ * @boost_voltage:	CPR boost voltage fuse parameter value (raw, not
+ *			converted to a voltage)
+ *
+ * This struct holds the values for all of the fuses read from memory.
+ */
+struct cpr4_msm8953_apss_fuses {
+	u64	ro_sel[MSM8953_APSS_FUSE_CORNERS];
+	u64	init_voltage[MSM8953_APSS_FUSE_CORNERS];
+	u64	target_quot[MSM8953_APSS_FUSE_CORNERS];
+	u64	quot_offset[MSM8953_APSS_FUSE_CORNERS];
+	u64	speed_bin;
+	u64	cpr_fusing_rev;
+	u64	boost_cfg;
+	u64	boost_voltage;
+	u64	misc;
+};
+
+/*
+ * fuse combo = fusing revision + 8 * (speed bin)
+ * where: fusing revision = 0 - 7 and speed bin = 0 - 7
+ */
+#define CPR4_MSM8953_APSS_FUSE_COMBO_COUNT	64
+
+/*
+ * Constants which define the name of each fuse corner.
+ */
+enum cpr4_msm8953_apss_fuse_corner {
+	CPR4_MSM8953_APSS_FUSE_CORNER_LOWSVS	= 0,
+	CPR4_MSM8953_APSS_FUSE_CORNER_SVS		= 1,
+	CPR4_MSM8953_APSS_FUSE_CORNER_NOM		= 2,
+	CPR4_MSM8953_APSS_FUSE_CORNER_TURBO_L1	= 3,
+};
+
+static const char * const cpr4_msm8953_apss_fuse_corner_name[] = {
+	[CPR4_MSM8953_APSS_FUSE_CORNER_LOWSVS]	= "LowSVS",
+	[CPR4_MSM8953_APSS_FUSE_CORNER_SVS]		= "SVS",
+	[CPR4_MSM8953_APSS_FUSE_CORNER_NOM]		= "NOM",
+	[CPR4_MSM8953_APSS_FUSE_CORNER_TURBO_L1]	= "TURBO_L1",
+};
+
+/*
+ * MSM8953 APSS fuse parameter locations:
+ *
+ * Structs are organized with the following dimensions:
+ *	Outer: 0 to 3 for fuse corners from lowest to highest corner
+ *	Inner: large enough to hold the longest set of parameter segments which
+ *		fully defines a fuse parameter, +1 (for NULL termination).
+ *		Each segment corresponds to a contiguous group of bits from a
+ *		single fuse row.  These segments are concatentated together in
+ *		order to form the full fuse parameter value.  The segments for
+ *		a given parameter may correspond to different fuse rows.
+ */
+static const struct cpr3_fuse_param
+msm8953_apss_ro_sel_param[MSM8953_APSS_FUSE_CORNERS][2] = {
+	{{73, 12, 15}, {} },
+	{{73,  8, 11}, {} },
+	{{73,  4,  7}, {} },
+	{{73,  0,  3}, {} },
+};
+
+static const struct cpr3_fuse_param
+msm8953_apss_init_voltage_param[MSM8953_APSS_FUSE_CORNERS][2] = {
+	{{71, 24, 29}, {} },
+	{{71, 18, 23}, {} },
+	{{71, 12, 17}, {} },
+	{{71,  6, 11}, {} },
+};
+
+static const struct cpr3_fuse_param
+msm8953_apss_target_quot_param[MSM8953_APSS_FUSE_CORNERS][2] = {
+	{{72, 44, 55}, {} },
+	{{72, 32, 43}, {} },
+	{{72, 20, 31}, {} },
+	{{72,  8, 19}, {} },
+};
+
+static const struct cpr3_fuse_param
+msm8953_apss_quot_offset_param[MSM8953_APSS_FUSE_CORNERS][2] = {
+	{{} },
+	{{71, 46, 52}, {} },
+	{{71, 39, 45}, {} },
+	{{71, 32, 38}, {} },
+};
+
+static const struct cpr3_fuse_param msm8953_cpr_fusing_rev_param[] = {
+	{71, 53, 55},
+	{},
+};
+
+static const struct cpr3_fuse_param msm8953_apss_speed_bin_param[] = {
+	{36, 40, 42},
+	{},
+};
+
+static const struct cpr3_fuse_param msm8953_cpr_boost_fuse_cfg_param[] = {
+	{36, 43, 45},
+	{},
+};
+
+static const struct cpr3_fuse_param msm8953_apss_boost_fuse_volt_param[] = {
+	{71, 0, 5},
+	{},
+};
+
+static const struct cpr3_fuse_param msm8953_misc_fuse_volt_adj_param[] = {
+	{36, 54, 54},
+	{},
+};
+
+/*
+ * The number of possible values for misc fuse is
+ * 2^(#bits defined for misc fuse)
+ */
+#define MSM8953_MISC_FUSE_VAL_COUNT		BIT(1)
+
+/*
+ * Open loop voltage fuse reference voltages in microvolts for MSM8953
+ */
+static const int msm8953_apss_fuse_ref_volt
+	[MSM8953_APSS_FUSE_CORNERS] = {
+	645000,
+	720000,
+	865000,
+	1065000,
+};
+
+#define MSM8953_APSS_FUSE_STEP_VOLT		10000
+#define MSM8953_APSS_VOLTAGE_FUSE_SIZE	6
+#define MSM8953_APSS_QUOT_OFFSET_SCALE	5
+
+#define MSM8953_APSS_CPR_SENSOR_COUNT	13
+
+#define MSM8953_APSS_CPR_CLOCK_RATE		19200000
+
+#define MSM8953_APSS_MAX_TEMP_POINTS	3
+#define MSM8953_APSS_TEMP_SENSOR_ID_START	4
+#define MSM8953_APSS_TEMP_SENSOR_ID_END	13
+/*
+ * Boost voltage fuse reference and ceiling voltages in microvolts for
+ * MSM8953.
+ */
+#define MSM8953_APSS_BOOST_FUSE_REF_VOLT	1140000
+#define MSM8953_APSS_BOOST_CEILING_VOLT	1140000
+#define MSM8953_APSS_BOOST_FLOOR_VOLT	900000
+#define MAX_BOOST_CONFIG_FUSE_VALUE		8
+
+#define MSM8953_APSS_CPR_SDELTA_CORE_COUNT	15
+
+/*
+ * Array of integer values mapped to each of the boost config fuse values to
+ * indicate boost enable/disable status.
+ */
+static bool boost_fuse[MAX_BOOST_CONFIG_FUSE_VALUE] = {0, 1, 1, 1, 1, 1, 1, 1};
+
+/**
+ * cpr4_msm8953_apss_read_fuse_data() - load APSS specific fuse parameter values
+ * @vreg:		Pointer to the CPR3 regulator
+ *
+ * This function allocates a cpr4_msm8953_apss_fuses struct, fills it with
+ * values read out of hardware fuses, and finally copies common fuse values
+ * into the CPR3 regulator struct.
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_msm8953_apss_read_fuse_data(struct cpr3_regulator *vreg)
+{
+	void __iomem *base = vreg->thread->ctrl->fuse_base;
+	struct cpr4_msm8953_apss_fuses *fuse;
+	int i, rc;
+
+	fuse = devm_kzalloc(vreg->thread->ctrl->dev, sizeof(*fuse), GFP_KERNEL);
+	if (!fuse)
+		return -ENOMEM;
+
+	rc = cpr3_read_fuse_param(base, msm8953_apss_speed_bin_param,
+				&fuse->speed_bin);
+	if (rc) {
+		cpr3_err(vreg, "Unable to read speed bin fuse, rc=%d\n", rc);
+		return rc;
+	}
+	cpr3_info(vreg, "speed bin = %llu\n", fuse->speed_bin);
+
+	rc = cpr3_read_fuse_param(base, msm8953_cpr_fusing_rev_param,
+				&fuse->cpr_fusing_rev);
+	if (rc) {
+		cpr3_err(vreg, "Unable to read CPR fusing revision fuse, rc=%d\n",
+			rc);
+		return rc;
+	}
+	cpr3_info(vreg, "CPR fusing revision = %llu\n", fuse->cpr_fusing_rev);
+
+	rc = cpr3_read_fuse_param(base, msm8953_misc_fuse_volt_adj_param,
+				&fuse->misc);
+	if (rc) {
+		cpr3_err(vreg, "Unable to read misc voltage adjustment fuse, rc=%d\n",
+			rc);
+		return rc;
+	}
+	cpr3_info(vreg, "CPR misc fuse value = %llu\n", fuse->misc);
+	if (fuse->misc >= MSM8953_MISC_FUSE_VAL_COUNT) {
+		cpr3_err(vreg, "CPR misc fuse value = %llu, should be < %lu\n",
+			fuse->misc, MSM8953_MISC_FUSE_VAL_COUNT);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < MSM8953_APSS_FUSE_CORNERS; i++) {
+		rc = cpr3_read_fuse_param(base,
+				msm8953_apss_init_voltage_param[i],
+				&fuse->init_voltage[i]);
+		if (rc) {
+			cpr3_err(vreg, "Unable to read fuse-corner %d initial voltage fuse, rc=%d\n",
+				i, rc);
+			return rc;
+		}
+
+		rc = cpr3_read_fuse_param(base,
+				msm8953_apss_target_quot_param[i],
+				&fuse->target_quot[i]);
+		if (rc) {
+			cpr3_err(vreg, "Unable to read fuse-corner %d target quotient fuse, rc=%d\n",
+				i, rc);
+			return rc;
+		}
+
+		rc = cpr3_read_fuse_param(base,
+				msm8953_apss_ro_sel_param[i],
+				&fuse->ro_sel[i]);
+		if (rc) {
+			cpr3_err(vreg, "Unable to read fuse-corner %d RO select fuse, rc=%d\n",
+				i, rc);
+			return rc;
+		}
+
+		rc = cpr3_read_fuse_param(base,
+				msm8953_apss_quot_offset_param[i],
+				&fuse->quot_offset[i]);
+		if (rc) {
+			cpr3_err(vreg, "Unable to read fuse-corner %d quotient offset fuse, rc=%d\n",
+				i, rc);
+			return rc;
+		}
+	}
+
+	rc = cpr3_read_fuse_param(base, msm8953_cpr_boost_fuse_cfg_param,
+				&fuse->boost_cfg);
+	if (rc) {
+		cpr3_err(vreg, "Unable to read CPR boost config fuse, rc=%d\n",
+			rc);
+		return rc;
+	}
+	cpr3_info(vreg, "Voltage boost fuse config = %llu boost = %s\n",
+			fuse->boost_cfg, boost_fuse[fuse->boost_cfg]
+			? "enable" : "disable");
+
+	rc = cpr3_read_fuse_param(base,
+				msm8953_apss_boost_fuse_volt_param,
+				&fuse->boost_voltage);
+	if (rc) {
+		cpr3_err(vreg, "failed to read boost fuse voltage, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	vreg->fuse_combo = fuse->cpr_fusing_rev + 8 * fuse->speed_bin;
+	if (vreg->fuse_combo >= CPR4_MSM8953_APSS_FUSE_COMBO_COUNT) {
+		cpr3_err(vreg, "invalid CPR fuse combo = %d found\n",
+			vreg->fuse_combo);
+		return -EINVAL;
+	}
+
+	vreg->speed_bin_fuse	= fuse->speed_bin;
+	vreg->cpr_rev_fuse	= fuse->cpr_fusing_rev;
+	vreg->fuse_corner_count	= MSM8953_APSS_FUSE_CORNERS;
+	vreg->platform_fuses	= fuse;
+
+	return 0;
+}
+
+/**
+ * cpr4_apss_parse_corner_data() - parse APSS corner data from device tree
+ *		properties of the CPR3 regulator's device node
+ * @vreg:		Pointer to the CPR3 regulator
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_parse_corner_data(struct cpr3_regulator *vreg)
+{
+	int rc;
+
+	rc = cpr3_parse_common_corner_data(vreg);
+	if (rc) {
+		cpr3_err(vreg, "error reading corner data, rc=%d\n", rc);
+		return rc;
+	}
+
+	return rc;
+}
+
+/**
+ * cpr4_apss_parse_misc_fuse_voltage_adjustments() - fill an array from a
+ *		portion of the voltage adjustments specified based on
+ *		miscellaneous fuse bits.
+ * @vreg:		Pointer to the CPR3 regulator
+ * @volt_adjust:	Voltage adjustment output data array which must be
+ *			of size vreg->corner_count
+ *
+ * cpr3_parse_common_corner_data() must be called for vreg before this function
+ * is called so that speed bin size elements are initialized.
+ *
+ * Two formats are supported for the device tree property:
+ * 1. Length == tuple_list_size * vreg->corner_count
+ *	(reading begins at index 0)
+ * 2. Length == tuple_list_size * vreg->speed_bin_corner_sum
+ *	(reading begins at index tuple_list_size * vreg->speed_bin_offset)
+ *
+ * Here, tuple_list_size is the number of possible values for misc fuse.
+ * All other property lengths are treated as errors.
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_parse_misc_fuse_voltage_adjustments(
+	struct cpr3_regulator *vreg, u32 *volt_adjust)
+{
+	struct device_node *node = vreg->of_node;
+	struct cpr4_msm8953_apss_fuses *fuse = vreg->platform_fuses;
+	int tuple_list_size = MSM8953_MISC_FUSE_VAL_COUNT;
+	int i, offset, rc, len = 0;
+	const char *prop_name = "qcom,cpr-misc-fuse-voltage-adjustment";
+
+	if (!of_find_property(node, prop_name, &len)) {
+		cpr3_err(vreg, "property %s is missing\n", prop_name);
+		return -EINVAL;
+	}
+
+	if (len == tuple_list_size * vreg->corner_count * sizeof(u32)) {
+		offset = 0;
+	} else if (vreg->speed_bin_corner_sum > 0 &&
+			len == tuple_list_size * vreg->speed_bin_corner_sum
+			* sizeof(u32)) {
+		offset = tuple_list_size * vreg->speed_bin_offset
+			+ fuse->misc * vreg->corner_count;
+	} else {
+		if (vreg->speed_bin_corner_sum > 0)
+			cpr3_err(vreg, "property %s has invalid length=%d, should be %zu or %zu\n",
+				prop_name, len,
+				tuple_list_size * vreg->corner_count
+					* sizeof(u32),
+				tuple_list_size * vreg->speed_bin_corner_sum
+					* sizeof(u32));
+		else
+			cpr3_err(vreg, "property %s has invalid length=%d, should be %zu\n",
+				prop_name, len,
+				tuple_list_size * vreg->corner_count
+				* sizeof(u32));
+		return -EINVAL;
+	}
+
+	for (i = 0; i < vreg->corner_count; i++) {
+		rc = of_property_read_u32_index(node, prop_name, offset + i,
+						&volt_adjust[i]);
+		if (rc) {
+			cpr3_err(vreg, "error reading property %s, rc=%d\n",
+				prop_name, rc);
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * cpr4_msm8953_apss_calculate_open_loop_voltages() - calculate the open-loop
+ *		voltage for each corner of a CPR3 regulator
+ * @vreg:		Pointer to the CPR3 regulator
+ *
+ * If open-loop voltage interpolation is allowed in device tree, then
+ * this function calculates the open-loop voltage for a given corner using
+ * linear interpolation.  This interpolation is performed using the processor
+ * frequencies of the lower and higher Fmax corners along with their fused
+ * open-loop voltages.
+ *
+ * If open-loop voltage interpolation is not allowed, then this function uses
+ * the Fmax fused open-loop voltage for all of the corners associated with a
+ * given fuse corner.
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_msm8953_apss_calculate_open_loop_voltages(
+			struct cpr3_regulator *vreg)
+{
+	struct device_node *node = vreg->of_node;
+	struct cpr4_msm8953_apss_fuses *fuse = vreg->platform_fuses;
+	int i, j, rc = 0;
+	bool allow_interpolation;
+	u64 freq_low, volt_low, freq_high, volt_high;
+	int *fuse_volt, *misc_adj_volt;
+	int *fmax_corner;
+
+	fuse_volt = kcalloc(vreg->fuse_corner_count, sizeof(*fuse_volt),
+				GFP_KERNEL);
+	fmax_corner = kcalloc(vreg->fuse_corner_count, sizeof(*fmax_corner),
+				GFP_KERNEL);
+	if (!fuse_volt || !fmax_corner) {
+		rc = -ENOMEM;
+		goto done;
+	}
+
+	for (i = 0; i < vreg->fuse_corner_count; i++) {
+		fuse_volt[i] = cpr3_convert_open_loop_voltage_fuse(
+			msm8953_apss_fuse_ref_volt[i],
+			MSM8953_APSS_FUSE_STEP_VOLT, fuse->init_voltage[i],
+			MSM8953_APSS_VOLTAGE_FUSE_SIZE);
+
+		/* Log fused open-loop voltage values for debugging purposes. */
+		cpr3_info(vreg, "fused %8s: open-loop=%7d uV\n",
+			  cpr4_msm8953_apss_fuse_corner_name[i],
+			  fuse_volt[i]);
+	}
+
+	rc = cpr3_adjust_fused_open_loop_voltages(vreg, fuse_volt);
+	if (rc) {
+		cpr3_err(vreg, "fused open-loop voltage adjustment failed, rc=%d\n",
+			rc);
+		goto done;
+	}
+
+	allow_interpolation = of_property_read_bool(node,
+				"qcom,allow-voltage-interpolation");
+
+	for (i = 1; i < vreg->fuse_corner_count; i++) {
+		if (fuse_volt[i] < fuse_volt[i - 1]) {
+			cpr3_info(vreg, "fuse corner %d voltage=%d uV < fuse corner %d voltage=%d uV; overriding: fuse corner %d voltage=%d\n",
+				i, fuse_volt[i], i - 1, fuse_volt[i - 1],
+				i, fuse_volt[i - 1]);
+			fuse_volt[i] = fuse_volt[i - 1];
+		}
+	}
+
+	if (!allow_interpolation) {
+		/* Use fused open-loop voltage for lower frequencies. */
+		for (i = 0; i < vreg->corner_count; i++)
+			vreg->corner[i].open_loop_volt
+				= fuse_volt[vreg->corner[i].cpr_fuse_corner];
+		goto done;
+	}
+
+	/* Determine highest corner mapped to each fuse corner */
+	j = vreg->fuse_corner_count - 1;
+	for (i = vreg->corner_count - 1; i >= 0; i--) {
+		if (vreg->corner[i].cpr_fuse_corner == j) {
+			fmax_corner[j] = i;
+			j--;
+		}
+	}
+	if (j >= 0) {
+		cpr3_err(vreg, "invalid fuse corner mapping\n");
+		rc = -EINVAL;
+		goto done;
+	}
+
+	/*
+	 * Interpolation is not possible for corners mapped to the lowest fuse
+	 * corner so use the fuse corner value directly.
+	 */
+	for (i = 0; i <= fmax_corner[0]; i++)
+		vreg->corner[i].open_loop_volt = fuse_volt[0];
+
+	/* Interpolate voltages for the higher fuse corners. */
+	for (i = 1; i < vreg->fuse_corner_count; i++) {
+		freq_low = vreg->corner[fmax_corner[i - 1]].proc_freq;
+		volt_low = fuse_volt[i - 1];
+		freq_high = vreg->corner[fmax_corner[i]].proc_freq;
+		volt_high = fuse_volt[i];
+
+		for (j = fmax_corner[i - 1] + 1; j <= fmax_corner[i]; j++)
+			vreg->corner[j].open_loop_volt = cpr3_interpolate(
+				freq_low, volt_low, freq_high, volt_high,
+				vreg->corner[j].proc_freq);
+	}
+
+done:
+	if (rc == 0) {
+		cpr3_debug(vreg, "unadjusted per-corner open-loop voltages:\n");
+		for (i = 0; i < vreg->corner_count; i++)
+			cpr3_debug(vreg, "open-loop[%2d] = %d uV\n", i,
+				vreg->corner[i].open_loop_volt);
+
+		rc = cpr3_adjust_open_loop_voltages(vreg);
+		if (rc)
+			cpr3_err(vreg, "open-loop voltage adjustment failed, rc=%d\n",
+				rc);
+
+		if (of_find_property(node,
+			"qcom,cpr-misc-fuse-voltage-adjustment",
+			NULL)) {
+			misc_adj_volt = kcalloc(vreg->corner_count,
+					sizeof(*misc_adj_volt), GFP_KERNEL);
+			if (!misc_adj_volt) {
+				rc = -ENOMEM;
+				goto _exit;
+			}
+
+			rc = cpr4_apss_parse_misc_fuse_voltage_adjustments(vreg,
+				misc_adj_volt);
+			if (rc) {
+				cpr3_err(vreg, "qcom,cpr-misc-fuse-voltage-adjustment reading failed, rc=%d\n",
+					rc);
+				kfree(misc_adj_volt);
+				goto _exit;
+			}
+
+			for (i = 0; i < vreg->corner_count; i++)
+				vreg->corner[i].open_loop_volt
+						+= misc_adj_volt[i];
+			kfree(misc_adj_volt);
+		}
+	}
+
+_exit:
+	kfree(fuse_volt);
+	kfree(fmax_corner);
+	return rc;
+}
+
+/**
+ * cpr4_msm8953_apss_set_no_interpolation_quotients() - use the fused target
+ *		quotient values for lower frequencies.
+ * @vreg:		Pointer to the CPR3 regulator
+ * @volt_adjust:	Pointer to array of per-corner closed-loop adjustment
+ *			voltages
+ * @volt_adjust_fuse:	Pointer to array of per-fuse-corner closed-loop
+ *			adjustment voltages
+ * @ro_scale:		Pointer to array of per-fuse-corner RO scaling factor
+ *			values with units of QUOT/V
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_msm8953_apss_set_no_interpolation_quotients(
+			struct cpr3_regulator *vreg, int *volt_adjust,
+			int *volt_adjust_fuse, int *ro_scale)
+{
+	struct cpr4_msm8953_apss_fuses *fuse = vreg->platform_fuses;
+	u32 quot, ro;
+	int quot_adjust;
+	int i, fuse_corner;
+
+	for (i = 0; i < vreg->corner_count; i++) {
+		fuse_corner = vreg->corner[i].cpr_fuse_corner;
+		quot = fuse->target_quot[fuse_corner];
+		quot_adjust = cpr3_quot_adjustment(ro_scale[fuse_corner],
+					   volt_adjust_fuse[fuse_corner] +
+					   volt_adjust[i]);
+		ro = fuse->ro_sel[fuse_corner];
+		vreg->corner[i].target_quot[ro] = quot + quot_adjust;
+		cpr3_debug(vreg, "corner=%d RO=%u target quot=%u\n",
+			  i, ro, quot);
+
+		if (quot_adjust)
+			cpr3_debug(vreg, "adjusted corner %d RO%u target quot: %u --> %u (%d uV)\n",
+				  i, ro, quot, vreg->corner[i].target_quot[ro],
+				  volt_adjust_fuse[fuse_corner] +
+				  volt_adjust[i]);
+	}
+
+	return 0;
+}
+
+/**
+ * cpr4_msm8953_apss_calculate_target_quotients() - calculate the CPR target
+ *		quotient for each corner of a CPR3 regulator
+ * @vreg:		Pointer to the CPR3 regulator
+ *
+ * If target quotient interpolation is allowed in device tree, then this
+ * function calculates the target quotient for a given corner using linear
+ * interpolation.  This interpolation is performed using the processor
+ * frequencies of the lower and higher Fmax corners along with the fused
+ * target quotient and quotient offset of the higher Fmax corner.
+ *
+ * If target quotient interpolation is not allowed, then this function uses
+ * the Fmax fused target quotient for all of the corners associated with a
+ * given fuse corner.
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_msm8953_apss_calculate_target_quotients(
+			struct cpr3_regulator *vreg)
+{
+	struct cpr4_msm8953_apss_fuses *fuse = vreg->platform_fuses;
+	int rc;
+	bool allow_interpolation;
+	u64 freq_low, freq_high, prev_quot;
+	u64 *quot_low;
+	u64 *quot_high;
+	u32 quot, ro;
+	int i, j, fuse_corner, quot_adjust;
+	int *fmax_corner;
+	int *volt_adjust, *volt_adjust_fuse, *ro_scale;
+	int *voltage_adj_misc;
+
+	/* Log fused quotient values for debugging purposes. */
+	cpr3_info(vreg, "fused   LowSVS: quot[%2llu]=%4llu\n",
+		fuse->ro_sel[CPR4_MSM8953_APSS_FUSE_CORNER_LOWSVS],
+		fuse->target_quot[CPR4_MSM8953_APSS_FUSE_CORNER_LOWSVS]);
+	for (i = CPR4_MSM8953_APSS_FUSE_CORNER_SVS;
+		i <= CPR4_MSM8953_APSS_FUSE_CORNER_TURBO_L1; i++)
+		cpr3_info(vreg, "fused %8s: quot[%2llu]=%4llu, quot_offset[%2llu]=%4llu\n",
+			cpr4_msm8953_apss_fuse_corner_name[i],
+			fuse->ro_sel[i], fuse->target_quot[i],
+			fuse->ro_sel[i], fuse->quot_offset[i] *
+			MSM8953_APSS_QUOT_OFFSET_SCALE);
+
+	allow_interpolation = of_property_read_bool(vreg->of_node,
+					"qcom,allow-quotient-interpolation");
+
+	volt_adjust = kcalloc(vreg->corner_count, sizeof(*volt_adjust),
+					GFP_KERNEL);
+	volt_adjust_fuse = kcalloc(vreg->fuse_corner_count,
+					sizeof(*volt_adjust_fuse), GFP_KERNEL);
+	ro_scale = kcalloc(vreg->fuse_corner_count, sizeof(*ro_scale),
+					GFP_KERNEL);
+	fmax_corner = kcalloc(vreg->fuse_corner_count, sizeof(*fmax_corner),
+					GFP_KERNEL);
+	quot_low = kcalloc(vreg->fuse_corner_count, sizeof(*quot_low),
+					GFP_KERNEL);
+	quot_high = kcalloc(vreg->fuse_corner_count, sizeof(*quot_high),
+					GFP_KERNEL);
+	if (!volt_adjust || !volt_adjust_fuse || !ro_scale ||
+	    !fmax_corner || !quot_low || !quot_high) {
+		rc = -ENOMEM;
+		goto done;
+	}
+
+	rc = cpr3_parse_closed_loop_voltage_adjustments(vreg, &fuse->ro_sel[0],
+				volt_adjust, volt_adjust_fuse, ro_scale);
+	if (rc) {
+		cpr3_err(vreg, "could not load closed-loop voltage adjustments, rc=%d\n",
+			rc);
+		goto done;
+	}
+
+	if (of_find_property(vreg->of_node,
+		"qcom,cpr-misc-fuse-voltage-adjustment", NULL)) {
+		voltage_adj_misc = kcalloc(vreg->corner_count,
+				sizeof(*voltage_adj_misc), GFP_KERNEL);
+		if (!voltage_adj_misc) {
+			rc = -ENOMEM;
+			goto done;
+		}
+
+		rc = cpr4_apss_parse_misc_fuse_voltage_adjustments(vreg,
+			voltage_adj_misc);
+		if (rc) {
+			cpr3_err(vreg, "qcom,cpr-misc-fuse-voltage-adjustment reading failed, rc=%d\n",
+				rc);
+			kfree(voltage_adj_misc);
+			goto done;
+		}
+
+		for (i = 0; i < vreg->corner_count; i++)
+			volt_adjust[i] += voltage_adj_misc[i];
+
+		kfree(voltage_adj_misc);
+	}
+
+	if (!allow_interpolation) {
+		/* Use fused target quotients for lower frequencies. */
+		return cpr4_msm8953_apss_set_no_interpolation_quotients(
+				vreg, volt_adjust, volt_adjust_fuse, ro_scale);
+	}
+
+	/* Determine highest corner mapped to each fuse corner */
+	j = vreg->fuse_corner_count - 1;
+	for (i = vreg->corner_count - 1; i >= 0; i--) {
+		if (vreg->corner[i].cpr_fuse_corner == j) {
+			fmax_corner[j] = i;
+			j--;
+		}
+	}
+	if (j >= 0) {
+		cpr3_err(vreg, "invalid fuse corner mapping\n");
+		rc = -EINVAL;
+		goto done;
+	}
+
+	/*
+	 * Interpolation is not possible for corners mapped to the lowest fuse
+	 * corner so use the fuse corner value directly.
+	 */
+	i = CPR4_MSM8953_APSS_FUSE_CORNER_LOWSVS;
+	quot_adjust = cpr3_quot_adjustment(ro_scale[i], volt_adjust_fuse[i]);
+	quot = fuse->target_quot[i] + quot_adjust;
+	quot_high[i] = quot_low[i] = quot;
+	ro = fuse->ro_sel[i];
+	if (quot_adjust)
+		cpr3_debug(vreg, "adjusted fuse corner %d RO%u target quot: %llu --> %u (%d uV)\n",
+			i, ro, fuse->target_quot[i], quot, volt_adjust_fuse[i]);
+
+	for (i = 0; i <= fmax_corner[CPR4_MSM8953_APSS_FUSE_CORNER_LOWSVS];
+		i++)
+		vreg->corner[i].target_quot[ro] = quot;
+
+	for (i = CPR4_MSM8953_APSS_FUSE_CORNER_SVS;
+	     i < vreg->fuse_corner_count; i++) {
+		quot_high[i] = fuse->target_quot[i];
+		if (fuse->ro_sel[i] == fuse->ro_sel[i - 1])
+			quot_low[i] = quot_high[i - 1];
+		else
+			quot_low[i] = quot_high[i]
+					- fuse->quot_offset[i]
+					  * MSM8953_APSS_QUOT_OFFSET_SCALE;
+		if (quot_high[i] < quot_low[i]) {
+			cpr3_debug(vreg, "quot_high[%d]=%llu < quot_low[%d]=%llu; overriding: quot_high[%d]=%llu\n",
+				i, quot_high[i], i, quot_low[i],
+				i, quot_low[i]);
+			quot_high[i] = quot_low[i];
+		}
+	}
+
+	/* Perform per-fuse-corner target quotient adjustment */
+	for (i = 1; i < vreg->fuse_corner_count; i++) {
+		quot_adjust = cpr3_quot_adjustment(ro_scale[i],
+						   volt_adjust_fuse[i]);
+		if (quot_adjust) {
+			prev_quot = quot_high[i];
+			quot_high[i] += quot_adjust;
+			cpr3_debug(vreg, "adjusted fuse corner %d RO%llu target quot: %llu --> %llu (%d uV)\n",
+				i, fuse->ro_sel[i], prev_quot, quot_high[i],
+				volt_adjust_fuse[i]);
+		}
+
+		if (fuse->ro_sel[i] == fuse->ro_sel[i - 1])
+			quot_low[i] = quot_high[i - 1];
+		else
+			quot_low[i] += cpr3_quot_adjustment(ro_scale[i],
+						    volt_adjust_fuse[i - 1]);
+
+		if (quot_high[i] < quot_low[i]) {
+			cpr3_debug(vreg, "quot_high[%d]=%llu < quot_low[%d]=%llu after adjustment; overriding: quot_high[%d]=%llu\n",
+				i, quot_high[i], i, quot_low[i],
+				i, quot_low[i]);
+			quot_high[i] = quot_low[i];
+		}
+	}
+
+	/* Interpolate voltages for the higher fuse corners. */
+	for (i = 1; i < vreg->fuse_corner_count; i++) {
+		freq_low = vreg->corner[fmax_corner[i - 1]].proc_freq;
+		freq_high = vreg->corner[fmax_corner[i]].proc_freq;
+
+		ro = fuse->ro_sel[i];
+		for (j = fmax_corner[i - 1] + 1; j <= fmax_corner[i]; j++)
+			vreg->corner[j].target_quot[ro] = cpr3_interpolate(
+				freq_low, quot_low[i], freq_high, quot_high[i],
+				vreg->corner[j].proc_freq);
+	}
+
+	/* Perform per-corner target quotient adjustment */
+	for (i = 0; i < vreg->corner_count; i++) {
+		fuse_corner = vreg->corner[i].cpr_fuse_corner;
+		ro = fuse->ro_sel[fuse_corner];
+		quot_adjust = cpr3_quot_adjustment(ro_scale[fuse_corner],
+						   volt_adjust[i]);
+		if (quot_adjust) {
+			prev_quot = vreg->corner[i].target_quot[ro];
+			vreg->corner[i].target_quot[ro] += quot_adjust;
+			cpr3_debug(vreg, "adjusted corner %d RO%u target quot: %llu --> %u (%d uV)\n",
+				i, ro, prev_quot,
+				vreg->corner[i].target_quot[ro],
+				volt_adjust[i]);
+		}
+	}
+
+	/* Ensure that target quotients increase monotonically */
+	for (i = 1; i < vreg->corner_count; i++) {
+		ro = fuse->ro_sel[vreg->corner[i].cpr_fuse_corner];
+		if (fuse->ro_sel[vreg->corner[i - 1].cpr_fuse_corner] == ro
+		    && vreg->corner[i].target_quot[ro]
+				< vreg->corner[i - 1].target_quot[ro]) {
+			cpr3_debug(vreg, "adjusted corner %d RO%u target quot=%u < adjusted corner %d RO%u target quot=%u; overriding: corner %d RO%u target quot=%u\n",
+				i, ro, vreg->corner[i].target_quot[ro],
+				i - 1, ro, vreg->corner[i - 1].target_quot[ro],
+				i, ro, vreg->corner[i - 1].target_quot[ro]);
+			vreg->corner[i].target_quot[ro]
+				= vreg->corner[i - 1].target_quot[ro];
+		}
+	}
+
+done:
+	kfree(volt_adjust);
+	kfree(volt_adjust_fuse);
+	kfree(ro_scale);
+	kfree(fmax_corner);
+	kfree(quot_low);
+	kfree(quot_high);
+	return rc;
+}
+
+/**
+ * cpr4_apss_print_settings() - print out APSS CPR configuration settings into
+ *		the kernel log for debugging purposes
+ * @vreg:		Pointer to the CPR3 regulator
+ */
+static void cpr4_apss_print_settings(struct cpr3_regulator *vreg)
+{
+	struct cpr3_corner *corner;
+	int i;
+
+	cpr3_debug(vreg, "Corner: Frequency (Hz), Fuse Corner, Floor (uV), Open-Loop (uV), Ceiling (uV)\n");
+	for (i = 0; i < vreg->corner_count; i++) {
+		corner = &vreg->corner[i];
+		cpr3_debug(vreg, "%3d: %10u, %2d, %7d, %7d, %7d\n",
+			i, corner->proc_freq, corner->cpr_fuse_corner,
+			corner->floor_volt, corner->open_loop_volt,
+			corner->ceiling_volt);
+	}
+
+	if (vreg->thread->ctrl->apm)
+		cpr3_debug(vreg, "APM threshold = %d uV, APM adjust = %d uV\n",
+			vreg->thread->ctrl->apm_threshold_volt,
+			vreg->thread->ctrl->apm_adj_volt);
+}
+
+/**
+ * cpr4_apss_init_thread() - perform steps necessary to initialize the
+ *		configuration data for a CPR3 thread
+ * @thread:		Pointer to the CPR3 thread
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_init_thread(struct cpr3_thread *thread)
+{
+	int rc;
+
+	rc = cpr3_parse_common_thread_data(thread);
+	if (rc) {
+		cpr3_err(thread->ctrl, "thread %u unable to read CPR thread data from device tree, rc=%d\n",
+			thread->thread_id, rc);
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * cpr4_apss_parse_temp_adj_properties() - parse temperature based
+ *		adjustment properties from device tree.
+ * @ctrl:	Pointer to the CPR3 controller
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_parse_temp_adj_properties(struct cpr3_controller *ctrl)
+{
+	struct device_node *of_node = ctrl->dev->of_node;
+	int rc, i, len, temp_point_count;
+
+	if (!of_find_property(of_node, "qcom,cpr-temp-point-map", &len)) {
+		/*
+		 * Temperature based adjustments are not defined. Single
+		 * temperature band is still valid for per-online-core
+		 * adjustments.
+		 */
+		ctrl->temp_band_count = 1;
+		return 0;
+	}
+
+	temp_point_count = len / sizeof(u32);
+	if (temp_point_count <= 0
+		|| temp_point_count > MSM8953_APSS_MAX_TEMP_POINTS) {
+		cpr3_err(ctrl, "invalid number of temperature points %d > %d (max)\n",
+			 temp_point_count, MSM8953_APSS_MAX_TEMP_POINTS);
+		return -EINVAL;
+	}
+
+	ctrl->temp_points = devm_kcalloc(ctrl->dev, temp_point_count,
+					sizeof(*ctrl->temp_points), GFP_KERNEL);
+	if (!ctrl->temp_points)
+		return -ENOMEM;
+
+	rc = of_property_read_u32_array(of_node, "qcom,cpr-temp-point-map",
+					ctrl->temp_points, temp_point_count);
+	if (rc) {
+		cpr3_err(ctrl, "error reading property qcom,cpr-temp-point-map, rc=%d\n",
+			 rc);
+		return rc;
+	}
+
+	for (i = 0; i < temp_point_count; i++)
+		cpr3_debug(ctrl, "Temperature Point %d=%d\n", i,
+				   ctrl->temp_points[i]);
+
+	/*
+	 * If t1, t2, and t3 are the temperature points, then the temperature
+	 * bands are: (-inf, t1], (t1, t2], (t2, t3], and (t3, inf).
+	 */
+	ctrl->temp_band_count = temp_point_count + 1;
+	cpr3_debug(ctrl, "Number of temp bands =%d\n", ctrl->temp_band_count);
+
+	rc = of_property_read_u32(of_node, "qcom,cpr-initial-temp-band",
+				  &ctrl->initial_temp_band);
+	if (rc) {
+		cpr3_err(ctrl, "error reading qcom,cpr-initial-temp-band, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	if (ctrl->initial_temp_band >= ctrl->temp_band_count) {
+		cpr3_err(ctrl, "Initial temperature band value %d should be in range [0 - %d]\n",
+			ctrl->initial_temp_band, ctrl->temp_band_count - 1);
+		return -EINVAL;
+	}
+
+	ctrl->temp_sensor_id_start = MSM8953_APSS_TEMP_SENSOR_ID_START;
+	ctrl->temp_sensor_id_end = MSM8953_APSS_TEMP_SENSOR_ID_END;
+	ctrl->allow_temp_adj = true;
+	return rc;
+}
+
+/**
+ * cpr4_apss_parse_boost_properties() - parse configuration data for boost
+ *		voltage adjustment for CPR3 regulator from device tree.
+ * @vreg:	Pointer to the CPR3 regulator
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_parse_boost_properties(struct cpr3_regulator *vreg)
+{
+	struct cpr3_controller *ctrl = vreg->thread->ctrl;
+	struct cpr4_msm8953_apss_fuses *fuse = vreg->platform_fuses;
+	struct cpr3_corner *corner;
+	int i, boost_voltage, final_boost_volt, rc = 0;
+	int *boost_table = NULL, *boost_temp_adj = NULL;
+	int boost_voltage_adjust = 0, boost_num_cores = 0;
+	u32 boost_allowed = 0;
+
+	if (!boost_fuse[fuse->boost_cfg])
+		/* Voltage boost is disabled in fuse */
+		return 0;
+
+	if (of_find_property(vreg->of_node, "qcom,allow-boost", NULL)) {
+		rc = cpr3_parse_array_property(vreg, "qcom,allow-boost", 1,
+				&boost_allowed);
+		if (rc)
+			return rc;
+	}
+
+	if (!boost_allowed) {
+		/* Voltage boost is not enabled for this regulator */
+		return 0;
+	}
+
+	boost_voltage = cpr3_convert_open_loop_voltage_fuse(
+				MSM8953_APSS_BOOST_FUSE_REF_VOLT,
+				MSM8953_APSS_FUSE_STEP_VOLT,
+				fuse->boost_voltage,
+				MSM8953_APSS_VOLTAGE_FUSE_SIZE);
+
+	/* Log boost voltage value for debugging purposes. */
+	cpr3_info(vreg, "Boost open-loop=%7d uV\n", boost_voltage);
+
+	if (of_find_property(vreg->of_node,
+			"qcom,cpr-boost-voltage-fuse-adjustment", NULL)) {
+		rc = cpr3_parse_array_property(vreg,
+			"qcom,cpr-boost-voltage-fuse-adjustment",
+			1, &boost_voltage_adjust);
+		if (rc) {
+			cpr3_err(vreg, "qcom,cpr-boost-voltage-fuse-adjustment reading failed, rc=%d\n",
+				rc);
+			return rc;
+		}
+
+		boost_voltage += boost_voltage_adjust;
+		/* Log boost voltage value for debugging purposes. */
+		cpr3_info(vreg, "Adjusted boost open-loop=%7d uV\n",
+			boost_voltage);
+	}
+
+	/* Limit boost voltage value between ceiling and floor voltage limits */
+	boost_voltage = min(boost_voltage, MSM8953_APSS_BOOST_CEILING_VOLT);
+	boost_voltage = max(boost_voltage, MSM8953_APSS_BOOST_FLOOR_VOLT);
+
+	/*
+	 * The boost feature can only be used for the highest voltage corner.
+	 * Also, keep core-count adjustments disabled when the boost feature
+	 * is enabled.
+	 */
+	corner = &vreg->corner[vreg->corner_count - 1];
+	if (!corner->sdelta) {
+		/*
+		 * If core-count/temp adjustments are not defined, the cpr4
+		 * sdelta for this corner will not be allocated. Allocate it
+		 * here for boost configuration.
+		 */
+		corner->sdelta = devm_kzalloc(ctrl->dev,
+					sizeof(*corner->sdelta), GFP_KERNEL);
+		if (!corner->sdelta)
+			return -ENOMEM;
+	}
+	corner->sdelta->temp_band_count = ctrl->temp_band_count;
+
+	rc = of_property_read_u32(vreg->of_node, "qcom,cpr-num-boost-cores",
+				&boost_num_cores);
+	if (rc) {
+		cpr3_err(vreg, "qcom,cpr-num-boost-cores reading failed, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	if (boost_num_cores <= 0
+		|| boost_num_cores > MSM8953_APSS_CPR_SDELTA_CORE_COUNT) {
+		cpr3_err(vreg, "Invalid boost number of cores = %d\n",
+			boost_num_cores);
+		return -EINVAL;
+	}
+	corner->sdelta->boost_num_cores = boost_num_cores;
+
+	boost_table = devm_kcalloc(ctrl->dev, corner->sdelta->temp_band_count,
+					sizeof(*boost_table), GFP_KERNEL);
+	if (!boost_table)
+		return -ENOMEM;
+
+	if (of_find_property(vreg->of_node,
+				"qcom,cpr-boost-temp-adjustment", NULL)) {
+		boost_temp_adj = kcalloc(corner->sdelta->temp_band_count,
+					sizeof(*boost_temp_adj), GFP_KERNEL);
+		if (!boost_temp_adj)
+			return -ENOMEM;
+
+		rc = cpr3_parse_array_property(vreg,
+				"qcom,cpr-boost-temp-adjustment",
+				corner->sdelta->temp_band_count,
+				boost_temp_adj);
+		if (rc) {
+			cpr3_err(vreg, "qcom,cpr-boost-temp-adjustment reading failed, rc=%d\n",
+				rc);
+			goto done;
+		}
+	}
+
+	for (i = 0; i < corner->sdelta->temp_band_count; i++) {
+		/* Apply static adjustments to boost voltage */
+		final_boost_volt = boost_voltage + (boost_temp_adj == NULL
+						? 0 : boost_temp_adj[i]);
+		/*
+		 * Limit final adjusted boost voltage value between ceiling
+		 * and floor voltage limits
+		 */
+		final_boost_volt = min(final_boost_volt,
+					MSM8953_APSS_BOOST_CEILING_VOLT);
+		final_boost_volt = max(final_boost_volt,
+					MSM8953_APSS_BOOST_FLOOR_VOLT);
+
+		boost_table[i] = (corner->open_loop_volt - final_boost_volt)
+					/ ctrl->step_volt;
+		cpr3_debug(vreg, "Adjusted boost voltage margin for temp band %d = %d steps\n",
+			i, boost_table[i]);
+	}
+
+	corner->ceiling_volt = MSM8953_APSS_BOOST_CEILING_VOLT;
+	corner->sdelta->boost_table = boost_table;
+	corner->sdelta->allow_boost = true;
+	corner->sdelta->allow_core_count_adj = false;
+	vreg->allow_boost = true;
+	ctrl->allow_boost = true;
+done:
+	kfree(boost_temp_adj);
+	return rc;
+}
+
+/**
+ * cpr4_apss_init_regulator() - perform all steps necessary to initialize the
+ *		configuration data for a CPR3 regulator
+ * @vreg:		Pointer to the CPR3 regulator
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_init_regulator(struct cpr3_regulator *vreg)
+{
+	struct cpr4_msm8953_apss_fuses *fuse;
+	int rc;
+
+	rc = cpr4_msm8953_apss_read_fuse_data(vreg);
+	if (rc) {
+		cpr3_err(vreg, "unable to read CPR fuse data, rc=%d\n", rc);
+		return rc;
+	}
+
+	fuse = vreg->platform_fuses;
+
+	rc = cpr4_apss_parse_corner_data(vreg);
+	if (rc) {
+		cpr3_err(vreg, "unable to read CPR corner data from device tree, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	rc = cpr3_mem_acc_init(vreg);
+	if (rc) {
+		if (rc != -EPROBE_DEFER)
+			cpr3_err(vreg, "unable to initialize mem-acc regulator settings, rc=%d\n",
+				 rc);
+		return rc;
+	}
+
+	rc = cpr4_msm8953_apss_calculate_open_loop_voltages(vreg);
+	if (rc) {
+		cpr3_err(vreg, "unable to calculate open-loop voltages, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	rc = cpr3_limit_open_loop_voltages(vreg);
+	if (rc) {
+		cpr3_err(vreg, "unable to limit open-loop voltages, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	cpr3_open_loop_voltage_as_ceiling(vreg);
+
+	rc = cpr3_limit_floor_voltages(vreg);
+	if (rc) {
+		cpr3_err(vreg, "unable to limit floor voltages, rc=%d\n", rc);
+		return rc;
+	}
+
+	rc = cpr4_msm8953_apss_calculate_target_quotients(vreg);
+	if (rc) {
+		cpr3_err(vreg, "unable to calculate target quotients, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	rc = cpr4_parse_core_count_temp_voltage_adj(vreg, false);
+	if (rc) {
+		cpr3_err(vreg, "unable to parse temperature and core count voltage adjustments, rc=%d\n",
+			 rc);
+		return rc;
+	}
+
+	if (vreg->allow_core_count_adj && (vreg->max_core_count <= 0
+				   || vreg->max_core_count >
+				   MSM8953_APSS_CPR_SDELTA_CORE_COUNT)) {
+		cpr3_err(vreg, "qcom,max-core-count has invalid value = %d\n",
+			 vreg->max_core_count);
+		return -EINVAL;
+	}
+
+	rc = cpr4_apss_parse_boost_properties(vreg);
+	if (rc) {
+		cpr3_err(vreg, "unable to parse boost adjustments, rc=%d\n",
+			 rc);
+		return rc;
+	}
+
+	cpr4_apss_print_settings(vreg);
+
+	return rc;
+}
+
+/**
+ * cpr4_apss_init_controller() - perform APSS CPR4 controller specific
+ *		initializations
+ * @ctrl:		Pointer to the CPR3 controller
+ *
+ * Return: 0 on success, errno on failure
+ */
+static int cpr4_apss_init_controller(struct cpr3_controller *ctrl)
+{
+	int rc;
+
+	rc = cpr3_parse_common_ctrl_data(ctrl);
+	if (rc) {
+		if (rc != -EPROBE_DEFER)
+			cpr3_err(ctrl, "unable to parse common controller data, rc=%d\n",
+				rc);
+		return rc;
+	}
+
+	rc = of_property_read_u32(ctrl->dev->of_node,
+				  "qcom,cpr-down-error-step-limit",
+				  &ctrl->down_error_step_limit);
+	if (rc) {
+		cpr3_err(ctrl, "error reading qcom,cpr-down-error-step-limit, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	rc = of_property_read_u32(ctrl->dev->of_node,
+				  "qcom,cpr-up-error-step-limit",
+				  &ctrl->up_error_step_limit);
+	if (rc) {
+		cpr3_err(ctrl, "error reading qcom,cpr-up-error-step-limit, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	/*
+	 * Use fixed step quotient if specified otherwise use dynamic
+	 * calculated per RO step quotient
+	 */
+	of_property_read_u32(ctrl->dev->of_node, "qcom,cpr-step-quot-fixed",
+			&ctrl->step_quot_fixed);
+	ctrl->use_dynamic_step_quot = ctrl->step_quot_fixed ? false : true;
+
+	ctrl->saw_use_unit_mV = of_property_read_bool(ctrl->dev->of_node,
+					"qcom,cpr-saw-use-unit-mV");
+
+	of_property_read_u32(ctrl->dev->of_node,
+			"qcom,cpr-voltage-settling-time",
+			&ctrl->voltage_settling_time);
+
+	ctrl->vdd_limit_regulator = devm_regulator_get(ctrl->dev, "vdd-limit");
+	if (IS_ERR(ctrl->vdd_limit_regulator)) {
+		rc = PTR_ERR(ctrl->vdd_limit_regulator);
+		if (rc != -EPROBE_DEFER)
+			cpr3_err(ctrl, "unable to request vdd-limit regulator, rc=%d\n",
+				rc);
+		return rc;
+	}
+
+	rc = cpr3_apm_init(ctrl);
+	if (rc) {
+		if (rc != -EPROBE_DEFER)
+			cpr3_err(ctrl, "unable to initialize APM settings, rc=%d\n",
+				rc);
+		return rc;
+	}
+
+	rc = cpr4_apss_parse_temp_adj_properties(ctrl);
+	if (rc) {
+		cpr3_err(ctrl, "unable to parse temperature adjustment properties, rc=%d\n",
+			 rc);
+		return rc;
+	}
+
+	ctrl->sensor_count = MSM8953_APSS_CPR_SENSOR_COUNT;
+
+	/*
+	 * APSS only has one thread (0) per controller so the zeroed
+	 * array does not need further modification.
+	 */
+	ctrl->sensor_owner = devm_kcalloc(ctrl->dev, ctrl->sensor_count,
+		sizeof(*ctrl->sensor_owner), GFP_KERNEL);
+	if (!ctrl->sensor_owner)
+		return -ENOMEM;
+
+	ctrl->cpr_clock_rate = MSM8953_APSS_CPR_CLOCK_RATE;
+	ctrl->ctrl_type = CPR_CTRL_TYPE_CPR4;
+	ctrl->supports_hw_closed_loop = true;
+	ctrl->use_hw_closed_loop = of_property_read_bool(ctrl->dev->of_node,
+						"qcom,cpr-hw-closed-loop");
+	return 0;
+}
+
+static int cpr4_apss_regulator_suspend(struct platform_device *pdev,
+				pm_message_t state)
+{
+	struct cpr3_controller *ctrl = platform_get_drvdata(pdev);
+
+	return cpr3_regulator_suspend(ctrl);
+}
+
+static int cpr4_apss_regulator_resume(struct platform_device *pdev)
+{
+	struct cpr3_controller *ctrl = platform_get_drvdata(pdev);
+
+	return cpr3_regulator_resume(ctrl);
+}
+
+static int cpr4_apss_regulator_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct cpr3_controller *ctrl;
+	int i, rc;
+
+	if (!dev->of_node) {
+		dev_err(dev, "Device tree node is missing\n");
+		return -EINVAL;
+	}
+
+	ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL);
+	if (!ctrl)
+		return -ENOMEM;
+
+	ctrl->dev = dev;
+	/* Set to false later if anything precludes CPR operation. */
+	ctrl->cpr_allowed_hw = true;
+
+	rc = of_property_read_string(dev->of_node, "qcom,cpr-ctrl-name",
+					&ctrl->name);
+	if (rc) {
+		cpr3_err(ctrl, "unable to read qcom,cpr-ctrl-name, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	rc = cpr3_map_fuse_base(ctrl, pdev);
+	if (rc) {
+		cpr3_err(ctrl, "could not map fuse base address\n");
+		return rc;
+	}
+
+	rc = cpr3_allocate_threads(ctrl, 0, 0);
+	if (rc) {
+		cpr3_err(ctrl, "failed to allocate CPR thread array, rc=%d\n",
+			rc);
+		return rc;
+	}
+
+	if (ctrl->thread_count != 1) {
+		cpr3_err(ctrl, "expected 1 thread but found %d\n",
+			ctrl->thread_count);
+		return -EINVAL;
+	}
+
+	rc = cpr4_apss_init_controller(ctrl);
+	if (rc) {
+		if (rc != -EPROBE_DEFER)
+			cpr3_err(ctrl, "failed to initialize CPR controller parameters, rc=%d\n",
+				rc);
+		return rc;
+	}
+
+	rc = cpr4_apss_init_thread(&ctrl->thread[0]);
+	if (rc) {
+		cpr3_err(ctrl, "thread initialization failed, rc=%d\n", rc);
+		return rc;
+	}
+
+	for (i = 0; i < ctrl->thread[0].vreg_count; i++) {
+		rc = cpr4_apss_init_regulator(&ctrl->thread[0].vreg[i]);
+		if (rc) {
+			cpr3_err(&ctrl->thread[0].vreg[i], "regulator initialization failed, rc=%d\n",
+				 rc);
+			return rc;
+		}
+	}
+
+	platform_set_drvdata(pdev, ctrl);
+
+	return cpr3_regulator_register(pdev, ctrl);
+}
+
+static int cpr4_apss_regulator_remove(struct platform_device *pdev)
+{
+	struct cpr3_controller *ctrl = platform_get_drvdata(pdev);
+
+	return cpr3_regulator_unregister(ctrl);
+}
+
+static const struct of_device_id cpr4_regulator_match_table[] = {
+	{ .compatible = "qcom,cpr4-msm8953-apss-regulator", },
+	{}
+};
+
+static struct platform_driver cpr4_apss_regulator_driver = {
+	.driver		= {
+		.name		= "qcom,cpr4-apss-regulator",
+		.of_match_table	= cpr4_regulator_match_table,
+		.owner		= THIS_MODULE,
+	},
+	.probe		= cpr4_apss_regulator_probe,
+	.remove		= cpr4_apss_regulator_remove,
+	.suspend	= cpr4_apss_regulator_suspend,
+	.resume		= cpr4_apss_regulator_resume,
+};
+
+static int cpr4_regulator_init(void)
+{
+	return platform_driver_register(&cpr4_apss_regulator_driver);
+}
+
+static void cpr4_regulator_exit(void)
+{
+	platform_driver_unregister(&cpr4_apss_regulator_driver);
+}
+
+MODULE_DESCRIPTION("CPR4 APSS regulator driver");
+MODULE_LICENSE("GPL v2");
+
+arch_initcall(cpr4_regulator_init);
+module_exit(cpr4_regulator_exit);