diff --git a/drivers/regulator/mt6315-regulator.c b/drivers/regulator/mt6315-regulator.c
index 9edc34981ee0..6b8be52c3772 100644
--- a/drivers/regulator/mt6315-regulator.c
+++ b/drivers/regulator/mt6315-regulator.c
@@ -59,7 +59,7 @@ static const struct linear_range mt_volt_range1[] = {
 	REGULATOR_LINEAR_RANGE(0, 0, 0xbf, 6250),
 };
 
-static unsigned int mt6315_map_mode(u32 mode)
+static unsigned int mt6315_map_mode(unsigned int mode)
 {
 	switch (mode) {
 	case MT6315_BUCK_MODE_AUTO: