diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 7a85ac9e32c5..1f9ff55b3620 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -131,6 +131,45 @@ static bool have_full_constraints(void)
 	return has_full_constraints || of_have_populated_dt();
 }
 
+/**
+ * regulator_lock_supply - lock a regulator and its supplies
+ * @rdev:         regulator source
+ */
+static void regulator_lock_supply(struct regulator_dev *rdev)
+{
+	struct regulator *supply;
+	int i = 0;
+
+	while (1) {
+		mutex_lock_nested(&rdev->mutex, i++);
+		supply = rdev->supply;
+
+		if (!rdev->supply)
+			return;
+
+		rdev = supply->rdev;
+	}
+}
+
+/**
+ * regulator_unlock_supply - unlock a regulator and its supplies
+ * @rdev:         regulator source
+ */
+static void regulator_unlock_supply(struct regulator_dev *rdev)
+{
+	struct regulator *supply;
+
+	while (1) {
+		mutex_unlock(&rdev->mutex);
+		supply = rdev->supply;
+
+		if (!rdev->supply)
+			return;
+
+		rdev = supply->rdev;
+	}
+}
+
 /**
  * of_get_regulator - get a regulator device node based on supply name
  * @dev: Device pointer for the consumer (of regulator) device