diff --git a/include/osmocom/abis/ipa.h b/include/osmocom/abis/ipa.h
index d455069..2254629 100644
--- a/include/osmocom/abis/ipa.h
+++ b/include/osmocom/abis/ipa.h
@@ -48,12 +48,13 @@
 	enum ipa_client_link_state	state;
 	const char			*addr;
 	uint16_t			port;
+	int (*connect_cb)(struct ipa_client_link *link);
 	int (*read_cb)(struct ipa_client_link *link, struct msgb *msg);
 	int (*write_cb)(struct ipa_client_link *link);
 	void				*data;
 };
 
-struct ipa_client_link *ipa_client_link_create(void *ctx, struct e1inp_ts *ts, const char *driver_name, int priv_nr, const char *addr, uint16_t port, int (*read_cb)(struct ipa_client_link *link, struct msgb *msgb), int (*write_cb)(struct ipa_client_link *link), void *data);
+struct ipa_client_link *ipa_client_link_create(void *ctx, struct e1inp_ts *ts, const char *driver_name, int priv_nr, const char *addr, uint16_t port, int (*connect)(struct ipa_client_link *link), int (*read_cb)(struct ipa_client_link *link, struct msgb *msgb), int (*write_cb)(struct ipa_client_link *link), void *data);
 void ipa_client_link_destroy(struct ipa_client_link *link);
 
 int ipa_client_write_default_cb(struct ipa_client_link *link);
diff --git a/include/osmocom/abis/ipaccess.h b/include/osmocom/abis/ipaccess.h
index 6816d87..7083ce9 100644
--- a/include/osmocom/abis/ipaccess.h
+++ b/include/osmocom/abis/ipaccess.h
@@ -104,7 +104,8 @@
 };
 
 struct hsl_unit {
-	unsigned long serno;
+	uint8_t swversion;
+	uint64_t serno;
 };
 
 #endif /* _OSMO_PROTO_IPACCESS_H */