diff --git a/Makefile b/Makefile
index 6ccb9316e..5ec49a6a6 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@ dep_jsx     = git-emqx https://github.com/talentdeficit/jsx 2.9.0
 dep_gproc   = git-emqx https://github.com/uwiger/gproc 0.8.0
 dep_gen_rpc = git-emqx https://github.com/emqx/gen_rpc 2.3.1
 dep_esockd  = git-emqx https://github.com/emqx/esockd v5.4.4
-dep_ekka    = git-emqx https://github.com/emqx/ekka v0.5.3
+dep_ekka    = git-emqx https://github.com/emqx/ekka v0.5.4
 dep_cowboy  = git-emqx https://github.com/ninenines/cowboy 2.6.1
 dep_replayq = git-emqx https://github.com/emqx/replayq v0.1.1
 
diff --git a/rebar.config b/rebar.config
index b73d8b0f9..d879b493c 100644
--- a/rebar.config
+++ b/rebar.config
@@ -7,10 +7,10 @@
 %% appended to deps in rebar.config.script
 {github_emqx_deps,
     [{gen_rpc, "2.3.1"},
-     {cuttlefish, "v2.2.1"},
-     {ekka, "v0.5.3"},
+     {ekka, "v0.5.4"},
      {replayq, "v0.1.1"},
-     {esockd, "v5.4.4"}
+     {esockd, "v5.4.4"},
+     {cuttlefish, "v2.2.1"}
     ]}.
 
 {edoc_opts, [{preprocess, true}]}.
diff --git a/src/emqx_protocol.erl b/src/emqx_protocol.erl
index 0a819f6c3..a8bc0b288 100644
--- a/src/emqx_protocol.erl
+++ b/src/emqx_protocol.erl
@@ -906,14 +906,6 @@ start_keepalive(Secs, #pstate{zone = Zone}) when Secs > 0 ->
     Backoff = emqx_zone:get_env(Zone, keepalive_backoff, 0.75),
     self() ! {keepalive, start, round(Secs * Backoff)}.
 
-rc(Reason) ->
-    case Reason of
-        protocol_error -> ?RC_PROTOCOL_ERROR;
-        topic_filters_invalid -> ?RC_TOPIC_FILTER_INVALID;
-        topic_name_invalid -> ?RC_TOPIC_NAME_INVALID;
-        _ -> ?RC_MALFORMED_PACKET
-    end.
-
 %%-----------------------------------------------------------------------------
 %% Parse topic filters
 %%-----------------------------------------------------------------------------