[PATCH] Fixup regulator_balance_voltage()

[Dmitry Osipenko]

---
 drivers/regulator/core.c | 39 ++++++++++++++++++++++++---------------
 1 file changed, 24 insertions(+), 15 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 282511508698..4a386fe9f26a 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -3187,7 +3187,8 @@ static int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
 	return ret;
 }
 
-static int regulator_get_optimal_voltage(struct regulator_dev *rdev)
+static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
+					 int *min_uV, int *max_uV)
 {
 	struct coupling_desc *c_desc = &rdev->coupling_desc;
 	struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
@@ -3211,7 +3212,9 @@ static int regulator_get_optimal_voltage(struct regulator_dev *rdev)
 	 * by consumers.
 	 */
 	if (n_coupled == 1) {
-		ret = desired_min_uV;
+		*min_uV = desired_min_uV;
+		*max_uV = desired_max_uV;
+		ret = 1;
 		goto out;
 	}
 
@@ -3285,8 +3288,10 @@ static int regulator_get_optimal_voltage(struct regulator_dev *rdev)
 		ret = -EINVAL;
 		goto out;
 	}
-	ret = possible_uV;
+	ret = (possible_uV == desired_min_uV);
 
+	*min_uV = possible_uV;
+	*max_uV = desired_max_uV;
 out:
 	return ret;
 }
@@ -3298,7 +3303,8 @@ static int regulator_balance_voltage(struct regulator_dev *rdev,
 	struct regulator_dev *best_rdev;
 	struct coupling_desc *c_desc = &rdev->coupling_desc;
 	int n_coupled;
-	int i, best_delta, best_uV, ret = 1;
+	int i, best_delta, best_min_uV, best_max_uV, ret = 1;
+	bool last = false;
 
 	c_rdevs = c_desc->coupled_rdevs;
 	n_coupled = c_desc->n_coupled;
@@ -3314,9 +3320,10 @@ static int regulator_balance_voltage(struct regulator_dev *rdev,
 	 * Find the best possible voltage change on each loop. Leave the loop
 	 * if there isn't any possible change.
 	 */
-	while (1) {
+	while (!last) {
 		best_delta = 0;
-		best_uV = 0;
+		best_min_uV = 0;
+		best_max_uV = 0;
 		best_rdev = NULL;
 
 		/*
@@ -3330,24 +3337,26 @@ static int regulator_balance_voltage(struct regulator_dev *rdev,
 			 * max_spread constraint in order to balance
 			 * the coupled voltages.
 			 */
-			int optimal_uV, current_uV;
+			int optimal_uV, optimal_max_uV, current_uV;
 
-			optimal_uV = regulator_get_optimal_voltage(c_rdevs[i]);
-			if (optimal_uV < 0) {
-				ret = optimal_uV;
+			ret = regulator_get_optimal_voltage(c_rdevs[i],
+							    &optimal_uV,
+							    &optimal_max_uV);
+			if (ret < 0)
 				goto out;
-			}
 
 			current_uV = _regulator_get_voltage(c_rdevs[i]);
 			if (current_uV < 0) {
-				ret = optimal_uV;
+				ret = current_uV;
 				goto out;
 			}
 
 			if (abs(best_delta) < abs(optimal_uV - current_uV)) {
 				best_delta = optimal_uV - current_uV;
 				best_rdev = c_rdevs[i];
-				best_uV = optimal_uV;
+				best_min_uV = optimal_uV;
+				best_max_uV = optimal_max_uV;
+				last = (best_rdev == rdev && ret > 0);
 			}
 		}
 
@@ -3357,8 +3366,8 @@ static int regulator_balance_voltage(struct regulator_dev *rdev,
 			goto out;
 		}
 
-		ret = regulator_set_voltage_rdev(best_rdev, best_uV,
-						 best_uV, state);
+		ret = regulator_set_voltage_rdev(best_rdev, best_min_uV,
+						 best_max_uV, state);
 
 		if (ret < 0)
 			goto out;
-- 
2.19.0