diff --git a/arch/arm/src/stm32/stm32_serial.c b/arch/arm/src/stm32/stm32_serial.c
index 097b2ec6ea..b58b4f78e7 100644
--- a/arch/arm/src/stm32/stm32_serial.c
+++ b/arch/arm/src/stm32/stm32_serial.c
@@ -986,11 +986,7 @@ static struct up_dev_s g_uart8priv =
 };
 #endif
 
-/* This table lets us iterate over the configured USARTs.
- *
- * REVISIT:  The following logic is not valid for the STM32F401 which
- * supports 3 USARTS:  USART1, USART2, and USART6.
- */
+/* This table lets us iterate over the configured USARTs */
 
 static struct up_dev_s *uart_devs[STM32_NUSART] =
 {
diff --git a/arch/arm/src/stm32/stm32_uart.h b/arch/arm/src/stm32/stm32_uart.h
index ecfc00296d..adbf9582f5 100644
--- a/arch/arm/src/stm32/stm32_uart.h
+++ b/arch/arm/src/stm32/stm32_uart.h
@@ -61,26 +61,26 @@
 /************************************************************************************
  * Pre-processor Definitions
  ************************************************************************************/
-/* Make sure that we have not enabled more U[S]ARTs than are support by
- * the device.
+/* Make sure that we have not enabled more U[S]ARTs than are supported by the
+ * device.
  */
 
-#if STM32_NUSART < 8 && !defined(CONFIG_STM32_HAVE_USART8)
+#if STM32_NUSART < 8 || !defined(CONFIG_STM32_HAVE_USART8)
 #  undef CONFIG_STM32_UART8
 #endif
-#if STM32_NUSART < 7 && !defined(CONFIG_STM32_HAVE_USART7)
+#if STM32_NUSART < 7 || !defined(CONFIG_STM32_HAVE_USART7)
 #  undef CONFIG_STM32_UART7
 #endif
-#if STM32_NUSART < 6 && !defined(CONFIG_STM32_HAVE_USART6)
+#if STM32_NUSART < 6 || !defined(CONFIG_STM32_HAVE_USART6)
 #  undef CONFIG_STM32_USART6
 #endif
-#if STM32_NUSART < 5 && !defined(CONFIG_STM32_HAVE_USART5)
+#if STM32_NUSART < 5 || !defined(CONFIG_STM32_HAVE_USART5)
 #  undef CONFIG_STM32_UART5
 #endif
-#if STM32_NUSART < 4 && !defined(CONFIG_STM32_HAVE_USART4)
+#if STM32_NUSART < 4 || !defined(CONFIG_STM32_HAVE_USART4)
 #  undef CONFIG_STM32_UART4
 #endif
-#if STM32_NUSART < 3 && !defined(CONFIG_STM32_HAVE_USART3)
+#if STM32_NUSART < 3 || !defined(CONFIG_STM32_HAVE_USART3)
 #  undef CONFIG_STM32_USART3
 #endif
 #if STM32_NUSART < 2