diff --git a/ot_mutex.h b/ot_mutex.h
index b2668ce..fd45397 100644
--- a/ot_mutex.h
+++ b/ot_mutex.h
@@ -34,7 +34,8 @@ typedef enum {
 
   TASK_CLEAN                       = 0x0300,
 
-  TASK_SYNC                        = 0x0400,
+  TASK_SYNC_OUT                    = 0x0400,
+  TASK_SYNC_IN                     = 0x0401,
 
   TASK_DMEM                        = 0x0500,