diff --git a/scst/include/scst.h b/scst/include/scst.h
index 68027ec4b..ecaf73e14 100644
--- a/scst/include/scst.h
+++ b/scst/include/scst.h
@@ -759,8 +759,6 @@ struct scst_opcode_descriptor;
  */
 #define NO_SUCH_LUN ((uint64_t)-1)
 
-typedef enum dma_data_direction scst_data_direction;
-
 /*
  * SCST target template: defines target driver's parameters and callback
  * functions.
diff --git a/scst/include/scst_const.h b/scst/include/scst_const.h
index cb0caa2ea..a232de5e9 100644
--- a/scst/include/scst_const.h
+++ b/scst/include/scst_const.h
@@ -239,11 +239,13 @@ enum scst_cdb_flags {
  ** Data direction aliases. Changing it don't forget to change
  ** scst_to_tgt_dma_dir and SCST_DATA_DIR_MAX as well!!
  *************************************************************/
-#define SCST_DATA_UNKNOWN		0
-#define SCST_DATA_WRITE			1
-#define SCST_DATA_READ			2
-#define SCST_DATA_BIDI			(SCST_DATA_WRITE | SCST_DATA_READ)
-#define SCST_DATA_NONE			4
+typedef enum scst_data_direction {
+	SCST_DATA_UNKNOWN	= 0,
+	SCST_DATA_WRITE		= 1,
+	SCST_DATA_READ		= 2,
+	SCST_DATA_BIDI		= (SCST_DATA_WRITE | SCST_DATA_READ),
+	SCST_DATA_NONE		= 4,
+} scst_data_direction;
 
 #define SCST_DATA_DIR_MAX		(SCST_DATA_NONE+1)