diff --git a/include/libopencm3/stm32/common/flash_common_f24.h b/include/libopencm3/stm32/common/flash_common_f24.h
index 79b1d248..c33d2dba 100644
--- a/include/libopencm3/stm32/common/flash_common_f24.h
+++ b/include/libopencm3/stm32/common/flash_common_f24.h
@@ -76,10 +76,12 @@
 #define FLASH_CR_PG			(1 << 0)
 #define FLASH_CR_SNB_SHIFT		3
 #define FLASH_CR_SNB_MASK		0x1f
-#define FLASH_CR_PROGRAM_X8		(0x00 << 8)
-#define FLASH_CR_PROGRAM_X16		(0x01 << 8)
-#define FLASH_CR_PROGRAM_X32		(0x02 << 8)
-#define FLASH_CR_PROGRAM_X64		(0x03 << 8)
+#define FLASH_CR_PROGRAM_MASK		0x3
+#define FLASH_CR_PROGRAM_SHIFT		8
+#define FLASH_CR_PROGRAM_X8		0
+#define FLASH_CR_PROGRAM_X16		1
+#define FLASH_CR_PROGRAM_X32		2
+#define FLASH_CR_PROGRAM_X64		3
 
 /* --- FLASH_OPTCR values -------------------------------------------------- */
 
diff --git a/lib/stm32/common/flash_common_f24.c b/lib/stm32/common/flash_common_f24.c
index 29f2b9e1..7d1ad373 100644
--- a/lib/stm32/common/flash_common_f24.c
+++ b/lib/stm32/common/flash_common_f24.c
@@ -38,8 +38,8 @@ programming manual for more information.
 
 static inline void flash_set_program_size(uint32_t psize)
 {
-	FLASH_CR &= ~(((1 << 0) | (1 << 1)) << 8);
-	FLASH_CR |= psize;
+	FLASH_CR &= ~(FLASH_CR_PROGRAM_MASK << FLASH_CR_PROGRAM_SHIFT);
+	FLASH_CR |= psize << FLASH_CR_PROGRAM_SHIFT;
 }
 
 /*---------------------------------------------------------------------------*/