diff --git a/include/dt-bindings/pinctrl/stm32-pinctrlf1.h b/include/dt-bindings/pinctrl/stm32-pinctrlf1.h
index b6a7a6b175d..5f267e37d8d 100644
--- a/include/dt-bindings/pinctrl/stm32-pinctrlf1.h
+++ b/include/dt-bindings/pinctrl/stm32-pinctrlf1.h
@@ -75,7 +75,7 @@
  * registers for particular pin.
  */
 
-#define STM32_PIN_USART_TX		(STM32_MODE_OUTPUT | STM32_CNF_ALT_FUNC | STM32_CNF_PUSH_PULL)
+#define STM32_PIN_USART_TX		(STM32_MODE_OUTPUT | STM32_CNF_ALT_FUNC | STM32_CNF_PUSH_PULL | STM32_PUPD_PULL_UP)
 #define STM32_PIN_USART_RX		(STM32_MODE_INPUT | STM32_CNF_IN_FLOAT)
 #define STM32_PIN_I2C			(STM32_MODE_OUTPUT | STM32_CNF_ALT_FUNC | STM32_CNF_OPEN_DRAIN)
 #define STM32_PIN_PWM			(STM32_MODE_OUTPUT | STM32_CNF_ALT_FUNC | STM32_CNF_PUSH_PULL)