diff --git a/targets/stm32l432/src/flash.c b/targets/stm32l432/src/flash.c
index 2b11c48..cbd10e9 100644
--- a/targets/stm32l432/src/flash.c
+++ b/targets/stm32l432/src/flash.c
@@ -29,6 +29,11 @@
 #include "log.h"
 #include "device.h"
 
+static void flash_lock()
+{
+    FLASH->CR |= (1U<<31);
+}
+
 static void flash_unlock()
 {
     if (FLASH->CR & FLASH_CR_LOCK)
@@ -197,8 +202,3 @@ void flash_write_fast(uint32_t addr, uint32_t * data)
     __enable_irq();
 
 }
-
-void flash_lock()
-{
-    FLASH->CR |= (1U<<31);
-}