diff --git a/drivers/usb/typec/ucsi/displayport.c b/drivers/usb/typec/ucsi/displayport.c
index 7067f2561b84..8d2032d0762c 100644
--- a/drivers/usb/typec/ucsi/displayport.c
+++ b/drivers/usb/typec/ucsi/displayport.c
@@ -74,7 +74,7 @@ static int ucsi_displayport_enter(struct typec_altmode *alt, u32 *vdo)
 		cur = 0xff;
 	}
 
-	if (cur != 0xff) {
+	if (cur < UCSI_MAX_ALTMODES) {
 		ret = dp->con->port_altmode[cur] == alt ? 0 : -EBUSY;
 		goto err_unlock;
 	}