diff --git a/gatchat/ppp_cp.c b/gatchat/ppp_cp.c
index 115fb65e..de6c7766 100644
--- a/gatchat/ppp_cp.c
+++ b/gatchat/ppp_cp.c
@@ -135,6 +135,40 @@ static int cp_transitions[16][10] = {
 { INV, INV, 2, 3, 4, 5, 6, 7, 8, SER|9 },
 };
 
+enum pppcp_code {
+	CONFIGURE_REQUEST = 1,
+	CONFIGURE_ACK,
+	CONFIGURE_NAK,
+	CONFIGURE_REJECT,
+	TERMINATE_REQUEST,
+	TERMINATE_ACK,
+	CODE_REJECT,
+	PROTOCOL_REJECT,
+	ECHO_REQUEST,
+	ECHO_REPLY,
+	DISCARD_REQUEST
+};
+
+#define LCP_SUPPORTED_CODES	((1 << CONFIGURE_REQUEST) | \
+				(1 << CONFIGURE_ACK) | \
+				(1 << CONFIGURE_NAK) | \
+				(1 << CONFIGURE_REJECT) | \
+				(1 << TERMINATE_REQUEST) | \
+				(1 << TERMINATE_ACK) | \
+				(1 << CODE_REJECT) | \
+				(1 << PROTOCOL_REJECT) | \
+				(1 << ECHO_REQUEST) | \
+				(1 << ECHO_REPLY) | \
+				(1 << DISCARD_REQUEST))
+
+#define IPCP_SUPPORTED_CODES	  ((1 << CONFIGURE_REQUEST) | \
+				  (1 << CONFIGURE_ACK) | \
+				  (1 << CONFIGURE_NAK) | \
+				  (1 << CONFIGURE_REJECT) | \
+				  (1 << TERMINATE_REQUEST) | \
+				  (1 << TERMINATE_ACK) | \
+				  (1 << CODE_REJECT))
+
 enum pppcp_event_type {
 	UP		= 0,
 	DOWN		= 1,
@@ -1256,6 +1290,7 @@ void pppcp_free(struct pppcp_data *data)
 struct pppcp_data *pppcp_new(GAtPPP *ppp, guint16 proto)
 {
 	struct pppcp_data *data;
+	guint16 codes;
 
 	data = g_try_malloc0(sizeof(struct pppcp_data));
 	if (!data)
@@ -1289,5 +1324,19 @@ struct pppcp_data *pppcp_new(GAtPPP *ppp, guint16 proto)
 	data->packet_ops[ECHO_REPLY - 1] = pppcp_process_echo_reply;
 	data->packet_ops[DISCARD_REQUEST - 1] = pppcp_process_discard_request;
 
+	switch (proto) {
+	case LCP_PROTOCOL:
+		codes = LCP_SUPPORTED_CODES;
+		break;
+	case IPCP_PROTO:
+		codes = IPCP_SUPPORTED_CODES;
+		break;
+	default:
+		codes = 0;
+		break;
+	}
+
+	pppcp_set_valid_codes(data, codes);
+
 	return data;
 }
diff --git a/gatchat/ppp_cp.h b/gatchat/ppp_cp.h
index 8d2975c1..43068212 100644
--- a/gatchat/ppp_cp.h
+++ b/gatchat/ppp_cp.h
@@ -21,20 +21,6 @@
 
 struct pppcp_data;
 
-enum pppcp_code {
-	CONFIGURE_REQUEST = 1,
-	CONFIGURE_ACK,
-	CONFIGURE_NAK,
-	CONFIGURE_REJECT,
-	TERMINATE_REQUEST,
-	TERMINATE_ACK,
-	CODE_REJECT,
-	PROTOCOL_REJECT,
-	ECHO_REQUEST,
-	ECHO_REPLY,
-	DISCARD_REQUEST
-};
-
 /* option format */
 struct ppp_option {
 	guint8 type;
diff --git a/gatchat/ppp_ipcp.c b/gatchat/ppp_ipcp.c
index ca4d0750..c3e781c7 100644
--- a/gatchat/ppp_ipcp.c
+++ b/gatchat/ppp_ipcp.c
@@ -44,14 +44,6 @@ struct ipcp_data {
 	struct pppcp_data *pppcp;
 };
 
-#define IPCP_SUPPORTED_CODES	  ((1 << CONFIGURE_REQUEST) | \
-				  (1 << CONFIGURE_ACK) | \
-				  (1 << CONFIGURE_NAK) | \
-				  (1 << CONFIGURE_REJECT) | \
-				  (1 << TERMINATE_REQUEST) | \
-				  (1 << TERMINATE_ACK) | \
-				  (1 << CODE_REJECT))
-
 enum ipcp_option_types {
 	IP_ADDRESSES		= 1,
 	IP_COMPRESSION_PROTO	= 2,
@@ -193,7 +185,7 @@ struct pppcp_data *ipcp_new(GAtPPP *ppp)
 		g_free(data);
 		return NULL;
 	}
-	pppcp_set_valid_codes(pppcp, IPCP_SUPPORTED_CODES);
+
 	pppcp->option_strings = ipcp_option_strings;
 	pppcp->prefix = "ipcp";
 	pppcp->priv = data;
diff --git a/gatchat/ppp_lcp.c b/gatchat/ppp_lcp.c
index 8ea6e56a..6460f336 100644
--- a/gatchat/ppp_lcp.c
+++ b/gatchat/ppp_lcp.c
@@ -46,18 +46,6 @@ enum lcp_options {
 	ACFC			= 8,
 };
 
-#define LCP_SUPPORTED_CODES	((1 << CONFIGURE_REQUEST) | \
-				(1 << CONFIGURE_ACK) | \
-				(1 << CONFIGURE_NAK) | \
-				(1 << CONFIGURE_REJECT) | \
-				(1 << TERMINATE_REQUEST) | \
-				(1 << TERMINATE_ACK) | \
-				(1 << CODE_REJECT) | \
-				(1 << PROTOCOL_REJECT) | \
-				(1 << ECHO_REQUEST) | \
-				(1 << ECHO_REPLY) | \
-				(1 << DISCARD_REQUEST))
-
 /*
  * signal the Up event to the NCP
  */
@@ -223,14 +211,13 @@ struct pppcp_data *lcp_new(GAtPPP *ppp)
 {
 	struct pppcp_data *pppcp;
 	struct ppp_option *option;
-	guint16 codes = LCP_SUPPORTED_CODES;
 
 	pppcp = pppcp_new(ppp, LCP_PROTOCOL);
 	if (!pppcp) {
 		g_print("Failed to allocate PPPCP struct\n");
 		return NULL;
 	}
-	pppcp_set_valid_codes(pppcp, codes);
+
 	pppcp->option_strings = lcp_option_strings;
 	pppcp->prefix = "lcp";
 	pppcp->priv = pppcp;