diff --git a/arch/arm/src/stm32/stm32_serial.c b/arch/arm/src/stm32/stm32_serial.c
index 1f7e64b775a..efb3d903d16 100644
--- a/arch/arm/src/stm32/stm32_serial.c
+++ b/arch/arm/src/stm32/stm32_serial.c
@@ -1980,7 +1980,9 @@ static int up_ioctl(struct file *filep, int cmd, unsigned long arg)
 #else
         if ((arg & SER_SINGLEWIRE_ENABLED) != 0)
           {
-            uint32_t gpio_val = GPIO_OPENDRAIN;
+            uint32_t gpio_val = (arg & SER_SINGLEWIRE_PUSHPULL) ==
+                                 SER_SINGLEWIRE_PUSHPULL ?
+                                 GPIO_PUSHPULL : GPIO_OPENDRAIN;
             gpio_val |= ((arg & SER_SINGLEWIRE_PULL_MASK) ==
                          SER_SINGLEWIRE_PULLUP) ? GPIO_PULLUP
                                                 : GPIO_FLOAT;