diff --git a/board/board-st-nucleo-l432.h b/board/board-st-nucleo-l432.h
index b538ced..95834a0 100644
--- a/board/board-st-nucleo-l432.h
+++ b/board/board-st-nucleo-l432.h
@@ -59,4 +59,4 @@
 #define VAL_GPIO_LED_AFRL    0x00000000
 #define VAL_GPIO_LED_AFRH    0x00000000
 
-#define RCC_PHR_GPIO   (RCC_PHR_GPIOA | RCC_PHR_GPIOB)
+#define RCC_AHB2_GPIO   (RCC_AHB2_GPIOA | RCC_AHB2_GPIOB)
diff --git a/mcu/clk_gpio_init-stm32l.c b/mcu/clk_gpio_init-stm32l.c
index 681f61b..b3a8ccf 100644
--- a/mcu/clk_gpio_init-stm32l.c
+++ b/mcu/clk_gpio_init-stm32l.c
@@ -69,12 +69,12 @@ void
 gpio_init (void)
 {
   /* Enable GPIO clock. */
-  RCC->AHB2ENR |= RCC_PHR_GPIO;
+  RCC->AHB2ENR |= RCC_AHB2_GPIO;
   /* Delay (more than two clocks) is needed.  */
-  while ((RCC->AHB2ENR & RCC_PHR_GPIO) == 0)
+  while ((RCC->AHB2ENR & RCC_AHB2_GPIO) == 0)
     ;
 
-  RCC->AHB2RSTR = RCC_PHR_GPIO;
+  RCC->AHB2RSTR = RCC_AHB2_GPIO;
   RCC->AHB2RSTR = 0;
 
   /* Delay (more than two clocks) is needed.  */
diff --git a/mcu/stm32l.h b/mcu/stm32l.h
index 2003f05..1f60f14 100644
--- a/mcu/stm32l.h
+++ b/mcu/stm32l.h
@@ -59,15 +59,15 @@ struct RCC {
 #define RCC_BASE		(AHB1PERIPH_BASE + 0x1000)
 static struct RCC *const RCC = (struct RCC *)RCC_BASE;
 
-#define RCC_PHR_GPIOA       0x00000001
-#define RCC_PHR_GPIOB       0x00000002
-#define RCC_PHR_GPIOC       0x00000004
-#define RCC_PHR_GPIOD       0x00000008
-#define RCC_PHR_GPIOE       0x00000010
-#define RCC_PHR_GPIOH       0x00000080
+#define RCC_AHB2_GPIOA       0x00000001
+#define RCC_AHB2_GPIOB       0x00000002
+#define RCC_AHB2_GPIOC       0x00000004
+#define RCC_AHB2_GPIOD       0x00000008
+#define RCC_AHB2_GPIOE       0x00000010
+#define RCC_AHB2_GPIOH       0x00000080
 
-#define RCC_PHR_USB         (1 << 26)
-#define RCC_PHR_CRS         (1 << 24)
+#define RCC_APB1_1_USB         (1 << 26)
+#define RCC_APB1_1_CRS         (1 << 24)
 
 
 struct PWR
diff --git a/mcu/sys-stm32l4.c b/mcu/sys-stm32l4.c
index 47f2cbd..d5dda21 100644
--- a/mcu/sys-stm32l4.c
+++ b/mcu/sys-stm32l4.c
@@ -47,8 +47,8 @@ static void wait (int count)
 void
 usb_lld_sys_shutdown (void)
 {
-  RCC->APB1ENR1 &= ~(RCC_PHR_USB | RCC_PHR_CRS);
-  RCC->APB1RSTR1 |= (RCC_PHR_USB | RCC_PHR_CRS);
+  RCC->APB1ENR1 &= ~(RCC_APB1_1_USB | RCC_APB1_1_CRS);
+  RCC->APB1RSTR1 |= (RCC_APB1_1_USB | RCC_APB1_1_CRS);
 }
 
 void
@@ -56,7 +56,8 @@ usb_lld_sys_init (void)
 {
   /* XXX: should configure CRS (clock recovery system) and HSI48 clock */
 
-  if ((RCC->APB1ENR1 & RCC_PHR_USB) && (RCC->APB1RSTR1 & RCC_PHR_USB) == 0)
+  if ((RCC->APB1ENR1 & RCC_APB1_1_USB)
+      && (RCC->APB1RSTR1 & RCC_APB1_1_USB) == 0)
     /* Make sure the device is disconnected, even after core reset.  */
     {
       usb_lld_sys_shutdown ();
@@ -64,8 +65,8 @@ usb_lld_sys_init (void)
       wait (5*MHZ);
     }
 
-  RCC->APB1ENR1 |= (RCC_PHR_USB | RCC_PHR_CRS);
-  RCC->APB1RSTR1 = (RCC_PHR_USB | RCC_PHR_CRS);
+  RCC->APB1ENR1 |= (RCC_APB1_1_USB | RCC_APB1_1_CRS);
+  RCC->APB1RSTR1 = (RCC_APB1_1_USB | RCC_APB1_1_CRS);
   RCC->APB1RSTR1 = 0;
 }