diff --git a/arch/arm/src/stm32/stm32_pwr.c b/arch/arm/src/stm32/stm32_pwr.c
index 73febc5180..e535ae2bc8 100644
--- a/arch/arm/src/stm32/stm32_pwr.c
+++ b/arch/arm/src/stm32/stm32_pwr.c
@@ -131,6 +131,7 @@ void stm32_pwr_enablebkp(bool writable)
  *
  ************************************************************************************/
 
+#if defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX)
 void stm32_pwr_enablebreg(bool regon)
 {
   uint16_t regval;
@@ -145,6 +146,7 @@ void stm32_pwr_enablebreg(bool regon)
       while ((stm32_pwr_getreg(STM32_PWR_CSR_OFFSET) & PWR_CSR_BRR) == 0);
     }
 }
+#endif
 
 /************************************************************************************
  * Name: stm32_pwr_setvos
diff --git a/arch/arm/src/stm32/stm32_pwr.h b/arch/arm/src/stm32/stm32_pwr.h
index 7559531a0e..46efb06a0b 100644
--- a/arch/arm/src/stm32/stm32_pwr.h
+++ b/arch/arm/src/stm32/stm32_pwr.h
@@ -102,7 +102,11 @@ void stm32_pwr_enablebkp(bool writable);
  *
  ************************************************************************************/
 
+#if defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX)
 void stm32_pwr_enablebreg(bool regon);
+#else
+#  define stm32_pwr_enablebreg(regon)
+#endif
 
 /************************************************************************************
  * Name: stm32_pwr_setvos