diff --git a/libraries/AP_HAL/Device.h b/libraries/AP_HAL/Device.h
index bf6fc8705e..b56a67932e 100644
--- a/libraries/AP_HAL/Device.h
+++ b/libraries/AP_HAL/Device.h
@@ -27,8 +27,8 @@
 class AP_HAL::Device {
 public:
     enum BusType {
-        I2C,
-        SPI,
+        BUS_TYPE_I2C,
+        BUS_TYPE_SPI,
     };
 
     enum Speed {
diff --git a/libraries/AP_HAL/I2CDevice.h b/libraries/AP_HAL/I2CDevice.h
index 68481872a4..278a7f0683 100644
--- a/libraries/AP_HAL/I2CDevice.h
+++ b/libraries/AP_HAL/I2CDevice.h
@@ -27,7 +27,7 @@ namespace AP_HAL {
 
 class I2CDevice : public Device {
 public:
-    I2CDevice() : Device(I2C) { }
+    I2CDevice() : Device(BUS_TYPE_I2C) { }
 
     virtual ~I2CDevice() { }
 
diff --git a/libraries/AP_HAL/SPIDevice.h b/libraries/AP_HAL/SPIDevice.h
index 917a5c5388..797ff03ccf 100644
--- a/libraries/AP_HAL/SPIDevice.h
+++ b/libraries/AP_HAL/SPIDevice.h
@@ -27,7 +27,7 @@ namespace AP_HAL {
 
 class SPIDevice : public Device {
 public:
-    SPIDevice() : Device(SPI) { }
+    SPIDevice() : Device(BUS_TYPE_SPI) { }
 
     virtual ~SPIDevice() { }
     /* Device implementation */
diff --git a/libraries/AP_InertialSensor/AP_InertialSensor_MPU6000.cpp b/libraries/AP_InertialSensor/AP_InertialSensor_MPU6000.cpp
index 87821da02d..3af669917e 100644
--- a/libraries/AP_InertialSensor/AP_InertialSensor_MPU6000.cpp
+++ b/libraries/AP_InertialSensor/AP_InertialSensor_MPU6000.cpp
@@ -297,7 +297,7 @@ void AP_InertialSensor_MPU6000::_fifo_enable()
 
 bool AP_InertialSensor_MPU6000::_has_auxiliary_bus()
 {
-    return _dev->bus_type != AP_HAL::Device::I2C;
+    return _dev->bus_type != AP_HAL::Device::BUS_TYPE_I2C;
 }
 
 void AP_InertialSensor_MPU6000::start()
@@ -610,7 +610,7 @@ bool AP_InertialSensor_MPU6000::_hardware_init(void)
         hal.scheduler->delay(100);
 
         /* bus-dependent initialization */
-        if (_dev->bus_type == AP_HAL::Device::SPI) {
+        if (_dev->bus_type == AP_HAL::Device::BUS_TYPE_SPI) {
             /* Disable I2C bus if SPI selected (Recommended in Datasheet to be
              * done just after the device is reset) */
             _register_write(MPUREG_USER_CTRL, BIT_USER_CTRL_I2C_IF_DIS);
diff --git a/libraries/AP_InertialSensor/AP_InertialSensor_MPU9250.cpp b/libraries/AP_InertialSensor/AP_InertialSensor_MPU9250.cpp
index d3ac71b5f1..5b7095cb22 100644
--- a/libraries/AP_InertialSensor/AP_InertialSensor_MPU9250.cpp
+++ b/libraries/AP_InertialSensor/AP_InertialSensor_MPU9250.cpp
@@ -276,7 +276,7 @@ bool AP_InertialSensor_MPU9250::_init()
 
 bool AP_InertialSensor_MPU9250::_has_auxiliary_bus()
 {
-    return _dev->bus_type != AP_HAL::Device::I2C;
+    return _dev->bus_type != AP_HAL::Device::BUS_TYPE_I2C;
 }
 
 void AP_InertialSensor_MPU9250::start()
@@ -484,7 +484,7 @@ bool AP_InertialSensor_MPU9250::_hardware_init(void)
         hal.scheduler->delay(100);
 
         /* bus-dependent initialization */
-        if (_dev->bus_type == AP_HAL::Device::SPI) {
+        if (_dev->bus_type == AP_HAL::Device::BUS_TYPE_SPI) {
             /* Disable I2C bus if SPI selected (Recommended in Datasheet to be
              * done just after the device is reset) */
             _register_write(MPUREG_USER_CTRL, BIT_USER_CTRL_I2C_IF_DIS);