diff --git a/arch/arm/src/kinetis/kinetis_spi.h b/arch/arm/src/kinetis/kinetis_spi.h
index bbc097199fe..8222af44246 100644
--- a/arch/arm/src/kinetis/kinetis_spi.h
+++ b/arch/arm/src/kinetis/kinetis_spi.h
@@ -63,8 +63,7 @@ extern "C"
  * Public Data
  ************************************************************************************/
 
-struct  spi_dev_s;
-enum    spi_dev_e;
+struct spi_dev_s;
 
 /****************************************************************************
  * Public Function Prototypes
diff --git a/arch/arm/src/stm32/stm32_spi.h b/arch/arm/src/stm32/stm32_spi.h
index e874441809b..9c757db523e 100644
--- a/arch/arm/src/stm32/stm32_spi.h
+++ b/arch/arm/src/stm32/stm32_spi.h
@@ -64,8 +64,7 @@ extern "C"
  * Public Data
  ************************************************************************************/
 
-struct  spi_dev_s;
-enum    spi_dev_e;
+struct spi_dev_s;
 
 /************************************************************************************
  * Public Functions
diff --git a/arch/arm/src/stm32f7/stm32_spi.h b/arch/arm/src/stm32f7/stm32_spi.h
index 475459a9a18..27751073564 100644
--- a/arch/arm/src/stm32f7/stm32_spi.h
+++ b/arch/arm/src/stm32f7/stm32_spi.h
@@ -63,8 +63,7 @@ extern "C"
 #define EXTERN extern
 #endif
 
-struct  spi_dev_s; /* Forward reference */
-enum    spi_dev_e; /* Forward reference */
+struct spi_dev_s; /* Forward reference */
 
 /************************************************************************************
  * Name: stm32_spibus_initialize
diff --git a/arch/arm/src/stm32l4/stm32l4_spi.h b/arch/arm/src/stm32l4/stm32l4_spi.h
index 77ba1a3f1b9..223cfb2b3df 100644
--- a/arch/arm/src/stm32l4/stm32l4_spi.h
+++ b/arch/arm/src/stm32l4/stm32l4_spi.h
@@ -64,8 +64,7 @@ extern "C"
  * Public Data
  ************************************************************************************/
 
-struct  spi_dev_s;
-enum    spi_dev_e;
+struct spi_dev_s;
 
 /************************************************************************************
  * Public Functions
diff --git a/arch/arm/src/xmc4/xmc4_spi.h b/arch/arm/src/xmc4/xmc4_spi.h
index f95257a320c..5113665eda2 100644
--- a/arch/arm/src/xmc4/xmc4_spi.h
+++ b/arch/arm/src/xmc4/xmc4_spi.h
@@ -63,8 +63,7 @@ extern "C"
  * Public Data
  ************************************************************************************/
 
-struct  spi_dev_s;
-enum    spi_dev_e;
+struct spi_dev_s;
 
 /****************************************************************************
  * Public Function Prototypes