diff --git a/arch/arm/src/stm32/stm32_serial.c b/arch/arm/src/stm32/stm32_serial.c
index ebb702ed4a9..d5ceed73ec6 100644
--- a/arch/arm/src/stm32/stm32_serial.c
+++ b/arch/arm/src/stm32/stm32_serial.c
@@ -2964,6 +2964,7 @@ static void up_txint(struct uart_dev_s *dev, bool enable)
 
       up_restoreusartint(priv, ie);
 
+#else
       /* Fake a TX interrupt here by just calling uart_xmitchars() with
        * interrupts disabled (note this may recurse).
        */