diff --git a/drivers/power/supply/rt9455_charger.c b/drivers/power/supply/rt9455_charger.c
index cfdbde9daf94..70722c070993 100644
--- a/drivers/power/supply/rt9455_charger.c
+++ b/drivers/power/supply/rt9455_charger.c
@@ -202,6 +202,7 @@ static const int rt9455_voreg_values[] = {
 	4450000, 4450000, 4450000, 4450000, 4450000, 4450000, 4450000, 4450000
 };
 
+#if IS_ENABLED(CONFIG_USB_PHY)
 /*
  * When the charger is in boost mode, REG02[7:2] represent boost output
  * voltage.
@@ -217,6 +218,7 @@ static const int rt9455_boost_voltage_values[] = {
 	5600000, 5600000, 5600000, 5600000, 5600000, 5600000, 5600000, 5600000,
 	5600000, 5600000, 5600000, 5600000, 5600000, 5600000, 5600000, 5600000,
 };
+#endif
 
 /* REG07[3:0] (VMREG) in uV */
 static const int rt9455_vmreg_values[] = {