[PATCH V2 5/8] PM / OPP: Add infrastructure to manage multiple regulators

[Viresh Kumar <viresh.kumar@linaro.org>]

This patch adds infrastructure to manage multiple regulators and updates
the only user (cpufreq-dt) of dev_pm_opp_set{put}_regulator().

This is preparatory work for adding full support for devices with
multiple regulators.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/base/power/opp/core.c    | 220 ++++++++++++++++++++++++++-------------
 drivers/base/power/opp/debugfs.c |  48 +++++++--
 drivers/base/power/opp/of.c      | 102 +++++++++++++-----
 drivers/base/power/opp/opp.h     |  10 +-
 drivers/cpufreq/cpufreq-dt.c     |   9 +-
 include/linux/pm_opp.h           |   8 +-
 6 files changed, 276 insertions(+), 121 deletions(-)

diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index 37fad2eb0f47..45c70ce07864 100644
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -93,6 +93,8 @@ struct opp_table *_find_opp_table(struct device *dev)
  * Return: voltage in micro volt corresponding to the opp, else
  * return 0
  *
+ * This is useful only for devices with single power supply.
+ *
  * Locking: This function must be called under rcu_read_lock(). opp is a rcu
  * protected pointer. This means that opp which could have been fetched by
  * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are
@@ -112,7 +114,7 @@ unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
 	if (IS_ERR_OR_NULL(tmp_opp))
 		pr_err("%s: Invalid parameters\n", __func__);
 	else
-		v = tmp_opp->supply.u_volt;
+		v = tmp_opp->supplies[0].u_volt;
 
 	return v;
 }
@@ -222,10 +224,10 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
 {
 	struct opp_table *opp_table;
 	struct dev_pm_opp *opp;
-	struct regulator *reg;
+	struct regulator *reg, **regulators;
 	unsigned long latency_ns = 0;
-	unsigned long min_uV = ~0, max_uV = 0;
-	int ret;
+	unsigned long *min_uV, *max_uV;
+	int ret, size, i, count;
 
 	rcu_read_lock();
 
@@ -235,21 +237,44 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
 		return 0;
 	}
 
-	reg = opp_table->regulator;
-	if (IS_ERR(reg)) {
+	count = opp_table->regulator_count;
+
+	if (!count) {
 		/* Regulator may not be required for device */
 		rcu_read_unlock();
 		return 0;
 	}
 
-	list_for_each_entry_rcu(opp, &opp_table->opp_list, node) {
-		if (!opp->available)
-			continue;
+	size = count * sizeof(*regulators);
+	regulators = kmemdup(opp_table->regulators, size, GFP_KERNEL);
+	if (!regulators) {
+		rcu_read_unlock();
+		return 0;
+	}
+
+	min_uV = kmalloc(count * (sizeof(*min_uV) + sizeof(*max_uV)),
+			 GFP_KERNEL);
+	if (!min_uV) {
+		kfree(regulators);
+		rcu_read_unlock();
+		return 0;
+	}
+
+	max_uV = min_uV + count;
+
+	for (i = 0; i < count; i++) {
+		min_uV[i] = ~0;
+		max_uV[i] = 0;
+
+		list_for_each_entry_rcu(opp, &opp_table->opp_list, node) {
+			if (!opp->available)
+				continue;
 
-		if (opp->supply.u_volt_min < min_uV)
-			min_uV = opp->supply.u_volt_min;
-		if (opp->supply.u_volt_max > max_uV)
-			max_uV = opp->supply.u_volt_max;
+			if (opp->supplies[i].u_volt_min < min_uV[i])
+				min_uV[i] = opp->supplies[i].u_volt_min;
+			if (opp->supplies[i].u_volt_max > max_uV[i])
+				max_uV[i] = opp->supplies[i].u_volt_max;
+		}
 	}
 
 	rcu_read_unlock();
@@ -258,9 +283,14 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
 	 * The caller needs to ensure that opp_table (and hence the regulator)
 	 * isn't freed, while we are executing this routine.
 	 */
-	ret = regulator_set_voltage_time(reg, min_uV, max_uV);
-	if (ret > 0)
-		latency_ns = ret * 1000;
+	for (i = 0; reg = regulators[i], i < count; i++) {
+		ret = regulator_set_voltage_time(reg, min_uV[i], max_uV[i]);
+		if (ret > 0)
+			latency_ns += ret * 1000;
+	}
+
+	kfree(min_uV);
+	kfree(regulators);
 
 	return latency_ns;
 }
@@ -580,7 +610,7 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 {
 	struct opp_table *opp_table;
 	struct dev_pm_opp *old_opp, *opp;
-	struct regulator *reg;
+	struct regulator *reg = ERR_PTR(-ENXIO);
 	struct clk *clk;
 	unsigned long freq, old_freq;
 	struct dev_pm_opp_supply old_supply, new_supply;
@@ -633,14 +663,23 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 		return ret;
 	}
 
+	if (opp_table->regulators) {
+		/* This function only supports single regulator per device */
+		if (WARN_ON(opp_table->regulator_count > 1)) {
+			dev_err(dev, "multiple regulators not supported\n");
+			rcu_read_unlock();
+			return -EINVAL;
+		}
+
+		reg = opp_table->regulators[0];
+	}
+
 	if (IS_ERR(old_opp))
 		old_supply.u_volt = 0;
 	else
-		memcpy(&old_supply, &old_opp->supply, sizeof(old_supply));
+		memcpy(&old_supply, old_opp->supplies, sizeof(old_supply));
 
-	memcpy(&new_supply, &opp->supply, sizeof(new_supply));
-
-	reg = opp_table->regulator;
+	memcpy(&new_supply, opp->supplies, sizeof(new_supply));
 
 	rcu_read_unlock();
 
@@ -764,9 +803,6 @@ static struct opp_table *_add_opp_table(struct device *dev)
 
 	_of_init_opp_table(opp_table, dev);
 
-	/* Set regulator to a non-NULL error value */
-	opp_table->regulator = ERR_PTR(-ENXIO);
-
 	/* Find clk for the device */
 	opp_table->clk = clk_get(dev, NULL);
 	if (IS_ERR(opp_table->clk)) {
@@ -815,7 +851,7 @@ static void _remove_opp_table(struct opp_table *opp_table)
 	if (opp_table->prop_name)
 		return;
 
-	if (!IS_ERR(opp_table->regulator))
+	if (opp_table->regulators)
 		return;
 
 	/* Release clk */
@@ -924,35 +960,49 @@ struct dev_pm_opp *_allocate_opp(struct device *dev,
 				 struct opp_table **opp_table)
 {
 	struct dev_pm_opp *opp;
+	int count, supply_size;
+	struct opp_table *table;
 
-	/* allocate new OPP node */
-	opp = kzalloc(sizeof(*opp), GFP_KERNEL);
-	if (!opp)
+	table = _add_opp_table(dev);
+	if (!table)
 		return NULL;
 
-	INIT_LIST_HEAD(&opp->node);
+	/* Allocate space for at least one supply */
+	count = table->regulator_count ? table->regulator_count : 1;
+	supply_size = sizeof(*opp->supplies) * count;
 
-	*opp_table = _add_opp_table(dev);
-	if (!*opp_table) {
-		kfree(opp);
+	/* allocate new OPP node + and supplies structures */
+	opp = kzalloc(sizeof(*opp) + supply_size, GFP_KERNEL);
+	if (!opp) {
+		kfree(table);
 		return NULL;
 	}
 
+	opp->supplies = (struct dev_pm_opp_supply *)(opp + 1);
+	INIT_LIST_HEAD(&opp->node);
+
+	*opp_table = table;
+
 	return opp;
 }
 
 static bool _opp_supported_by_regulators(struct dev_pm_opp *opp,
 					 struct opp_table *opp_table)
 {
-	struct regulator *reg = opp_table->regulator;
-
-	if (!IS_ERR(reg) &&
-	    !regulator_is_supported_voltage(reg, opp->supply.u_volt_min,
-					    opp->supply.u_volt_max)) {
-		pr_warn("%s: OPP minuV: %lu maxuV: %lu, not supported by regulator\n",
-			__func__, opp->supply.u_volt_min,
-			opp->supply.u_volt_max);
-		return false;
+	struct regulator *reg;
+	int i;
+
+	for (i = 0; i < opp_table->regulator_count; i++) {
+		reg = opp_table->regulators[i];
+
+		if (!regulator_is_supported_voltage(reg,
+					opp->supplies[i].u_volt_min,
+					opp->supplies[i].u_volt_max)) {
+			pr_warn("%s: OPP minuV: %lu maxuV: %lu, not supported by regulator\n",
+				__func__, opp->supplies[i].u_volt_min,
+				opp->supplies[i].u_volt_max);
+			return false;
+		}
 	}
 
 	return true;
@@ -984,12 +1034,13 @@ int _opp_add(struct device *dev, struct dev_pm_opp *new_opp,
 
 		/* Duplicate OPPs */
 		dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n",
-			 __func__, opp->rate, opp->supply.u_volt,
-			 opp->available, new_opp->rate, new_opp->supply.u_volt,
-			 new_opp->available);
+			 __func__, opp->rate, opp->supplies[0].u_volt,
+			 opp->available, new_opp->rate,
+			 new_opp->supplies[0].u_volt, new_opp->available);
 
+		/* Should we compare voltages for all regulators here ? */
 		return opp->available &&
-		       new_opp->supply.u_volt == opp->supply.u_volt ? 0 : -EEXIST;
+		       new_opp->supplies[0].u_volt == opp->supplies[0].u_volt ? 0 : -EEXIST;
 	}
 
 	new_opp->opp_table = opp_table;
@@ -1056,9 +1107,9 @@ int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt,
 	/* populate the opp table */
 	new_opp->rate = freq;
 	tol = u_volt * opp_table->voltage_tolerance_v1 / 100;
-	new_opp->supply.u_volt = u_volt;
-	new_opp->supply.u_volt_min = u_volt - tol;
-	new_opp->supply.u_volt_max = u_volt + tol;
+	new_opp->supplies[0].u_volt = u_volt;
+	new_opp->supplies[0].u_volt_min = u_volt - tol;
+	new_opp->supplies[0].u_volt_max = u_volt + tol;
 	new_opp->available = true;
 	new_opp->dynamic = dynamic;
 
@@ -1303,12 +1354,14 @@ void dev_pm_opp_put_prop_name(struct device *dev)
 EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name);
 
 /**
- * dev_pm_opp_set_regulator() - Set regulator name for the device
+ * dev_pm_opp_set_regulators() - Set regulator names for the device
  * @dev: Device for which regulator name is being set.
- * @name: Name of the regulator.
+ * @names: Array of pointers to the names of the regulator.
+ * @count: Number of regulators.
  *
  * In order to support OPP switching, OPP layer needs to know the name of the
- * device's regulator, as the core would be required to switch voltages as well.
+ * device's regulators, as the core would be required to switch voltages as
+ * well.
  *
  * This must be called before any OPPs are initialized for the device.
  *
@@ -1318,11 +1371,12 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name);
  * that this function is *NOT* called under RCU protection or in contexts where
  * mutex cannot be locked.
  */
-int dev_pm_opp_set_regulator(struct device *dev, const char *name)
+int dev_pm_opp_set_regulators(struct device *dev, const char *names[],
+			      unsigned int count)
 {
 	struct opp_table *opp_table;
 	struct regulator *reg;
-	int ret;
+	int ret, i;
 
 	mutex_lock(&opp_table_lock);
 
@@ -1338,26 +1392,43 @@ int dev_pm_opp_set_regulator(struct device *dev, const char *name)
 		goto err;
 	}
 
-	/* Already have a regulator set */
-	if (WARN_ON(!IS_ERR(opp_table->regulator))) {
+	/* Already have regulators set */
+	if (WARN_ON(opp_table->regulators)) {
 		ret = -EBUSY;
 		goto err;
 	}
-	/* Allocate the regulator */
-	reg = regulator_get_optional(dev, name);
-	if (IS_ERR(reg)) {
-		ret = PTR_ERR(reg);
-		if (ret != -EPROBE_DEFER)
-			dev_err(dev, "%s: no regulator (%s) found: %d\n",
-				__func__, name, ret);
+
+	opp_table->regulators = kmalloc_array(count,
+					      sizeof(*opp_table->regulators),
+					      GFP_KERNEL);
+	if (!opp_table->regulators)
 		goto err;
+
+	for (i = 0; i < count; i++) {
+		reg = regulator_get_optional(dev, names[i]);
+		pr_info("%s: %d: %p: %s\n", __func__, __LINE__, reg, names[i]);
+		if (IS_ERR(reg)) {
+			ret = PTR_ERR(reg);
+			if (ret != -EPROBE_DEFER)
+				dev_err(dev, "%s: regulator (%s) not found: %d\n",
+					__func__, names[i], ret);
+			goto free_regulators;
+		}
+
+		opp_table->regulators[i] = reg;
 	}
 
-	opp_table->regulator = reg;
+	opp_table->regulator_count = count;
 
 	mutex_unlock(&opp_table_lock);
 	return 0;
 
+free_regulators:
+	while (i != 0)
+		regulator_put(opp_table->regulators[--i]);
+
+	kfree(opp_table->regulators);
+	opp_table->regulators = NULL;
 err:
 	_remove_opp_table(opp_table);
 unlock:
@@ -1365,11 +1436,11 @@ int dev_pm_opp_set_regulator(struct device *dev, const char *name)
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulator);
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulators);
 
 /**
- * dev_pm_opp_put_regulator() - Releases resources blocked for regulator
- * @dev: Device for which regulator was set.
+ * dev_pm_opp_put_regulators() - Releases resources blocked for regulators
+ * @dev: Device for which regulators were set.
  *
  * Locking: The internal opp_table and opp structures are RCU protected.
  * Hence this function internally uses RCU updater strategy with mutex locks
@@ -1377,9 +1448,10 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulator);
  * that this function is *NOT* called under RCU protection or in contexts where
  * mutex cannot be locked.
  */
-void dev_pm_opp_put_regulator(struct device *dev)
+void dev_pm_opp_put_regulators(struct device *dev)
 {
 	struct opp_table *opp_table;
+	int i;
 
 	mutex_lock(&opp_table_lock);
 
@@ -1391,16 +1463,20 @@ void dev_pm_opp_put_regulator(struct device *dev)
 		goto unlock;
 	}
 
-	if (IS_ERR(opp_table->regulator)) {
-		dev_err(dev, "%s: Doesn't have regulator set\n", __func__);
+	if (!opp_table->regulators) {
+		dev_err(dev, "%s: Doesn't have regulators set\n", __func__);
 		goto unlock;
 	}
 
 	/* Make sure there are no concurrent readers while updating opp_table */
 	WARN_ON(!list_empty(&opp_table->opp_list));
 
-	regulator_put(opp_table->regulator);
-	opp_table->regulator = ERR_PTR(-ENXIO);
+	for (i = opp_table->regulator_count - 1; i >= 0; i--)
+		regulator_put(opp_table->regulators[i]);
+
+	kfree(opp_table->regulators);
+	opp_table->regulators = NULL;
+	opp_table->regulator_count = 0;
 
 	/* Try freeing opp_table if this was the last blocking resource */
 	_remove_opp_table(opp_table);
@@ -1408,7 +1484,7 @@ void dev_pm_opp_put_regulator(struct device *dev)
 unlock:
 	mutex_unlock(&opp_table_lock);
 }
-EXPORT_SYMBOL_GPL(dev_pm_opp_put_regulator);
+EXPORT_SYMBOL_GPL(dev_pm_opp_put_regulators);
 
 /**
  * dev_pm_opp_add()  - Add an OPP table from a table definitions
diff --git a/drivers/base/power/opp/debugfs.c b/drivers/base/power/opp/debugfs.c
index c897676ca35f..cb5e5fde3d39 100644
--- a/drivers/base/power/opp/debugfs.c
+++ b/drivers/base/power/opp/debugfs.c
@@ -34,6 +34,43 @@ void opp_debug_remove_one(struct dev_pm_opp *opp)
 	debugfs_remove_recursive(opp->dentry);
 }
 
+static bool opp_debug_create_supplies(struct dev_pm_opp *opp,
+				      struct opp_table *opp_table,
+				      struct dentry *pdentry)
+{
+	struct dentry *d;
+	int i = 0;
+	char name[] = "supply-X"; /* support only 0-9 supplies */
+
+	/* Always create at least supply-0 directory */
+	do {
+		name[7] = i + '0';
+
+		/* Create per-opp directory */
+		d = debugfs_create_dir(name, pdentry);
+		if (!d)
+			return false;
+
+		if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d,
+					  &opp->supplies[i].u_volt))
+			return false;
+
+		if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d,
+					  &opp->supplies[i].u_volt_min))
+			return false;
+
+		if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d,
+					  &opp->supplies[i].u_volt_max))
+			return false;
+
+		if (!debugfs_create_ulong("u_amp", S_IRUGO, d,
+					  &opp->supplies[i].u_amp))
+			return false;
+	} while (++i < opp_table->regulator_count);
+
+	return true;
+}
+
 int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
 {
 	struct dentry *pdentry = opp_table->dentry;
@@ -63,16 +100,7 @@ int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
 	if (!debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate))
 		return -ENOMEM;
 
-	if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d, &opp->supply.u_volt))
-		return -ENOMEM;
-
-	if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d, &opp->supply.u_volt_min))
-		return -ENOMEM;
-
-	if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d, &opp->supply.u_volt_max))
-		return -ENOMEM;
-
-	if (!debugfs_create_ulong("u_amp", S_IRUGO, d, &opp->supply.u_amp))
+	if (!opp_debug_create_supplies(opp, opp_table, d))
 		return -ENOMEM;
 
 	if (!debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
diff --git a/drivers/base/power/opp/of.c b/drivers/base/power/opp/of.c
index b7fcd0a1b58b..c857fb07a5bc 100644
--- a/drivers/base/power/opp/of.c
+++ b/drivers/base/power/opp/of.c
@@ -17,6 +17,7 @@
 #include <linux/errno.h>
 #include <linux/device.h>
 #include <linux/of.h>
+#include <linux/slab.h>
 #include <linux/export.h>
 
 #include "opp.h"
@@ -105,12 +106,13 @@ static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 			      struct opp_table *opp_table)
 {
-	u32 microvolt[3] = {0};
-	u32 val;
-	int count, ret;
+	u32 *microvolt, *microamp = NULL;
+	int supplies, vcount, icount, ret, i, j;
 	struct property *prop = NULL;
 	char name[NAME_MAX];
 
+	supplies = opp_table->regulator_count ? opp_table->regulator_count : 1;
+
 	/* Search for "opp-microvolt-<name>" */
 	if (opp_table->prop_name) {
 		snprintf(name, sizeof(name), "opp-microvolt-%s",
@@ -128,34 +130,29 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 			return 0;
 	}
 
-	count = of_property_count_u32_elems(opp->np, name);
-	if (count < 0) {
+	vcount = of_property_count_u32_elems(opp->np, name);
+	if (vcount < 0) {
 		dev_err(dev, "%s: Invalid %s property (%d)\n",
-			__func__, name, count);
-		return count;
+			__func__, name, vcount);
+		return vcount;
 	}
 
-	/* There can be one or three elements here */
-	if (count != 1 && count != 3) {
-		dev_err(dev, "%s: Invalid number of elements in %s property (%d)\n",
-			__func__, name, count);
+	/* There can be one or three elements per supply */
+	if (vcount != supplies && vcount != supplies * 3) {
+		dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
+			__func__, name, vcount, supplies);
 		return -EINVAL;
 	}
 
-	ret = of_property_read_u32_array(opp->np, name, microvolt, count);
+	microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
+	if (!microvolt)
+		return -ENOMEM;
+
+	ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 	if (ret) {
 		dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
-		return -EINVAL;
-	}
-
-	opp->supply.u_volt = microvolt[0];
-
-	if (count == 1) {
-		opp->supply.u_volt_min = opp->supply.u_volt;
-		opp->supply.u_volt_max = opp->supply.u_volt;
-	} else {
-		opp->supply.u_volt_min = microvolt[1];
-		opp->supply.u_volt_max = microvolt[2];
+		ret = -EINVAL;
+		goto free_microvolt;
 	}
 
 	/* Search for "opp-microamp-<name>" */
@@ -172,10 +169,59 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 		prop = of_find_property(opp->np, name, NULL);
 	}
 
-	if (prop && !of_property_read_u32(opp->np, name, &val))
-		opp->supply.u_amp = val;
+	if (prop) {
+		icount = of_property_count_u32_elems(opp->np, name);
+		if (icount < 0) {
+			dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
+				name, icount);
+			ret = icount;
+			goto free_microvolt;
+		}
 
-	return 0;
+		if (icount != supplies) {
+			dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
+				__func__, name, icount, supplies);
+			ret = -EINVAL;
+			goto free_microvolt;
+		}
+
+		microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
+		if (!microamp) {
+			ret = -EINVAL;
+			goto free_microvolt;
+		}
+
+		ret = of_property_read_u32_array(opp->np, name, microamp,
+						 icount);
+		if (ret) {
+			dev_err(dev, "%s: error parsing %s: %d\n", __func__,
+				name, ret);
+			ret = -EINVAL;
+			goto free_microamp;
+		}
+	}
+
+	for (i = 0, j = 0; i < supplies; i++) {
+		opp->supplies[i].u_volt = microvolt[j++];
+
+		if (vcount == supplies) {
+			opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
+			opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
+		} else {
+			opp->supplies[i].u_volt_min = microvolt[j++];
+			opp->supplies[i].u_volt_max = microvolt[j++];
+		}
+
+		if (microamp)
+			opp->supplies[i].u_amp = microamp[i];
+	}
+
+free_microamp:
+	kfree(microamp);
+free_microvolt:
+	kfree(microvolt);
+
+	return ret;
 }
 
 /**
@@ -304,8 +350,8 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np)
 
 	pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 		 __func__, new_opp->turbo, new_opp->rate,
-		 new_opp->supply.u_volt, new_opp->supply.u_volt_min,
-		 new_opp->supply.u_volt_max, new_opp->clock_latency_ns);
+		 new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
+		 new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 
 	/*
 	 * Notify the changes in the availability of the operable
diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h
index 1bda0d35c486..d3f0861f9bff 100644
--- a/drivers/base/power/opp/opp.h
+++ b/drivers/base/power/opp/opp.h
@@ -77,7 +77,7 @@ struct dev_pm_opp_supply {
  * @turbo:	true if turbo (boost) OPP
  * @suspend:	true if suspend OPP
  * @rate:	Frequency in hertz
- * @supply:	Power supply voltage/current values
+ * @supplies:	Power supplies voltage/current values
  * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
  *		frequency from any other OPP's frequency.
  * @opp_table:	points back to the opp_table struct this opp belongs to
@@ -96,7 +96,7 @@ struct dev_pm_opp {
 	bool suspend;
 	unsigned long rate;
 
-	struct dev_pm_opp_supply supply;
+	struct dev_pm_opp_supply *supplies;
 
 	unsigned long clock_latency_ns;
 
@@ -155,7 +155,8 @@ enum opp_table_access {
  * @supported_hw_count: Number of elements in supported_hw array.
  * @prop_name: A name to postfix to many DT properties, while parsing them.
  * @clk: Device's clock handle
- * @regulator: Supply regulator
+ * @regulators: Supply regulators
+ * @regulator_count: Number of Power Supply regulators
  * @dentry:	debugfs dentry pointer of the real device directory (not links).
  * @dentry_name: Name of the real dentry.
  *
@@ -190,7 +191,8 @@ struct opp_table {
 	unsigned int supported_hw_count;
 	const char *prop_name;
 	struct clk *clk;
-	struct regulator *regulator;
+	struct regulator **regulators;
+	unsigned int regulator_count;
 
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *dentry;
diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
index 5c07ae05d69a..15cb26118dc7 100644
--- a/drivers/cpufreq/cpufreq-dt.c
+++ b/drivers/cpufreq/cpufreq-dt.c
@@ -186,7 +186,10 @@ static int cpufreq_init(struct cpufreq_policy *policy)
 	 */
 	name = find_supply_name(cpu_dev);
 	if (name) {
-		ret = dev_pm_opp_set_regulator(cpu_dev, name);
+		const char *names[] = {name};
+
+		ret = dev_pm_opp_set_regulators(cpu_dev, names,
+						ARRAY_SIZE(names));
 		if (ret) {
 			dev_err(cpu_dev, "Failed to set regulator for cpu%d: %d\n",
 				policy->cpu, ret);
@@ -285,7 +288,7 @@ static int cpufreq_init(struct cpufreq_policy *policy)
 out_free_opp:
 	dev_pm_opp_of_cpumask_remove_table(policy->cpus);
 	if (name)
-		dev_pm_opp_put_regulator(cpu_dev);
+		dev_pm_opp_put_regulators(cpu_dev);
 out_put_clk:
 	clk_put(cpu_clk);
 
@@ -300,7 +303,7 @@ static int cpufreq_exit(struct cpufreq_policy *policy)
 	dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
 	dev_pm_opp_of_cpumask_remove_table(policy->related_cpus);
 	if (priv->reg_name)
-		dev_pm_opp_put_regulator(priv->cpu_dev);
+		dev_pm_opp_put_regulators(priv->cpu_dev);
 
 	clk_put(policy->clk);
 	kfree(priv);
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index bca26157f5b6..0606b70a8b97 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -62,8 +62,8 @@ int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions,
 void dev_pm_opp_put_supported_hw(struct device *dev);
 int dev_pm_opp_set_prop_name(struct device *dev, const char *name);
 void dev_pm_opp_put_prop_name(struct device *dev);
-int dev_pm_opp_set_regulator(struct device *dev, const char *name);
-void dev_pm_opp_put_regulator(struct device *dev);
+int dev_pm_opp_set_regulators(struct device *dev, const char *names[], unsigned int count);
+void dev_pm_opp_put_regulators(struct device *dev);
 int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq);
 int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const struct cpumask *cpumask);
 int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask);
@@ -170,12 +170,12 @@ static inline int dev_pm_opp_set_prop_name(struct device *dev, const char *name)
 
 static inline void dev_pm_opp_put_prop_name(struct device *dev) {}
 
-static inline int dev_pm_opp_set_regulator(struct device *dev, const char *name)
+static inline int dev_pm_opp_set_regulators(struct device *dev, const char *names[], unsigned int count)
 {
 	return -ENOTSUPP;
 }
 
-static inline void dev_pm_opp_put_regulator(struct device *dev) {}
+static inline void dev_pm_opp_put_regulators(struct device *dev) {}
 
 static inline int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 {
-- 
2.7.1.410.g6faf27b