diff --git a/apps/emqx_exproto/src/emqx_exproto_channel.erl b/apps/emqx_exproto/src/emqx_exproto_channel.erl
index be609860e..67f85f932 100644
--- a/apps/emqx_exproto/src/emqx_exproto_channel.erl
+++ b/apps/emqx_exproto/src/emqx_exproto_channel.erl
@@ -106,7 +106,7 @@
 info(Channel) ->
     maps:from_list(info(?INFO_KEYS, Channel)).
 
--spec(info(list(atom())|atom(), channel()) -> term()).
+-spec(info(list(atom()) | atom(), channel()) -> term()).
 info(Keys, Channel) when is_list(Keys) ->
     [{Key, info(Key, Channel)} || Key <- Keys];
 info(conninfo, #channel{conninfo = ConnInfo}) ->
diff --git a/apps/emqx_exproto/src/emqx_exproto_conn.erl b/apps/emqx_exproto/src/emqx_exproto_conn.erl
index 685a05687..02c0b31d6 100644
--- a/apps/emqx_exproto/src/emqx_exproto_conn.erl
+++ b/apps/emqx_exproto/src/emqx_exproto_conn.erl
@@ -115,7 +115,7 @@ start_link(esockd_transport, Sock, Options) ->
 %%--------------------------------------------------------------------
 
 %% @doc Get infos of the connection/channel.
--spec(info(pid()|state()) -> emqx_types:infos()).
+-spec(info(pid() | state()) -> emqx_types:infos()).
 info(CPid) when is_pid(CPid) ->
     call(CPid, info);
 info(State = #state{channel = Channel}) ->
@@ -137,7 +137,7 @@ info(sockstate, #state{sockstate = SockSt}) ->
 info(active_n, #state{active_n = ActiveN}) ->
     ActiveN.
 
--spec(stats(pid()|state()) -> emqx_types:stats()).
+-spec(stats(pid() | state()) -> emqx_types:stats()).
 stats(CPid) when is_pid(CPid) ->
     call(CPid, stats);
 stats(#state{socket  = Socket,
@@ -341,7 +341,7 @@ cancel_stats_timer(State) -> State.
 
 process_msg([], Parent, State) -> recvloop(Parent, State);
 
-process_msg([Msg|More], Parent, State) ->
+process_msg([Msg | More], Parent, State) ->
     case catch handle_msg(Msg, State) of
         ok ->
             process_msg(More, Parent, State);
@@ -417,7 +417,7 @@ handle_msg({Passive, _Sock}, State)
 
 handle_msg(Deliver = {deliver, _Topic, _Msg},
            State = #state{active_n = ActiveN}) ->
-    Delivers = [Deliver|emqx_misc:drain_deliver(ActiveN)],
+    Delivers = [Deliver | emqx_misc:drain_deliver(ActiveN)],
     with_channel(handle_deliver, [Delivers], State);
 
 %% Something sent
@@ -605,9 +605,9 @@ handle_outgoing(IoData, State = #state{socket = Socket}) ->
 handle_info(activate_socket, State = #state{sockstate = OldSst}) ->
     case activate_socket(State) of
         {ok, NState = #state{sockstate = NewSst}} ->
-            if OldSst =/= NewSst ->
-                   {ok, {event, NewSst}, NState};
-               true -> {ok, NState}
+            case OldSst =/= NewSst of
+                true -> {ok, {event, NewSst}, NState};
+                false -> {ok, NState}
             end;
         {error, Reason} ->
             handle_info({sock_error, Reason}, State)