diff --git a/firmware/config/stm32h7ems/halconf.h b/firmware/config/stm32h7ems/halconf.h
index 9b9c976328..f31859afb7 100644
--- a/firmware/config/stm32h7ems/halconf.h
+++ b/firmware/config/stm32h7ems/halconf.h
@@ -210,7 +210,7 @@
  * @note    Disabling this option saves both code and data space.
  */
 #if !defined(PAL_USE_CALLBACKS) || defined(__DOXYGEN__)
-#define PAL_USE_CALLBACKS                   FALSE
+#define PAL_USE_CALLBACKS                   TRUE
 #endif
 
 /**
diff --git a/firmware/controllers/can/can_vss.h b/firmware/controllers/can/can_vss.h
index 7f80119be9..d1c03496e8 100644
--- a/firmware/controllers/can/can_vss.h
+++ b/firmware/controllers/can/can_vss.h
@@ -8,6 +8,9 @@
 #pragma once
 
 float getVehicleCanSpeed(void);
-void processCanRxVss(const CANRxFrame& frame, efitick_t nowNt);
 void initCanVssSupport(Logging *logger_ptr);
-void setCanVss(int type);
\ No newline at end of file
+void setCanVss(int type);
+
+#if EFI_CAN_SUPPORT
+void processCanRxVss(const CANRxFrame& frame, efitick_t nowNt);
+#endif
diff --git a/firmware/hw_layer/ports/stm32/stm32f4/device_mpu_util.h b/firmware/hw_layer/ports/stm32/stm32f4/device_mpu_util.h
index 43fa7f0122..fe61adb2fa 100644
--- a/firmware/hw_layer/ports/stm32/stm32f4/device_mpu_util.h
+++ b/firmware/hw_layer/ports/stm32/stm32f4/device_mpu_util.h
@@ -1,5 +1,5 @@
 /**
- * @file	mpu_util.h
+ * @file	device_mpu_util.h
  *
  * @date Jul 27, 2014
  * @author Andrey Belomutskiy, (c) 2012-2020
diff --git a/firmware/hw_layer/ports/stm32/stm32f7/device_mpu_util.h b/firmware/hw_layer/ports/stm32/stm32f7/device_mpu_util.h
index 21d0400c9a..b1108a1d3b 100644
--- a/firmware/hw_layer/ports/stm32/stm32f7/device_mpu_util.h
+++ b/firmware/hw_layer/ports/stm32/stm32f7/device_mpu_util.h
@@ -1,5 +1,5 @@
 /**
- * @file	mpu_util.h
+ * @file	device_mpu_util.h
  *
  * @date Jul 27, 2014
  * @author Andrey Belomutskiy, (c) 2012-2020
diff --git a/firmware/hw_layer/ports/stm32/stm32h7/device_mpu_util.h b/firmware/hw_layer/ports/stm32/stm32h7/device_mpu_util.h
index d1b6312f44..7463b16bca 100644
--- a/firmware/hw_layer/ports/stm32/stm32h7/device_mpu_util.h
+++ b/firmware/hw_layer/ports/stm32/stm32h7/device_mpu_util.h
@@ -1,6 +1,13 @@
+/**
+ * @file	device_mpu_util.h
+ *
+ * @date Feb 5, 2021
+ * @author Andrey Belomutskiy, (c) 2012-2021
+ */
+
 #pragma once
 
 #include "stm32h7xx_hal_flash_ex.h"
 
 
-// todo SPI!
\ No newline at end of file
+// todo SPI! #2284