diff --git a/include/osmocom/abis/e1_input.h b/include/osmocom/abis/e1_input.h
new file mode 100644
index 0000000..c5a4137
--- /dev/null
+++ b/include/osmocom/abis/e1_input.h
@@ -0,0 +1,225 @@
+#ifndef _E1_INPUT_H
+#define _E1_INPUT_H
+
+#include <stdlib.h>
+#include <netinet/in.h>
+
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/timer.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/select.h>
+#include <osmocom/abis/subchan_demux.h>
+
+#define NUM_E1_TS   32
+
+enum e1inp_sign_type {
+	E1INP_SIGN_NONE,
+	E1INP_SIGN_OML,
+	E1INP_SIGN_RSL,
+};
+const char *e1inp_signtype_name(enum e1inp_sign_type tp);
+
+struct e1inp_ts;
+
+struct e1inp_sign_link {
+	/* list of signalling links */
+	struct llist_head list;
+
+	/* to which timeslot do we belong? */
+	struct e1inp_ts *ts;
+
+	enum e1inp_sign_type type;
+
+	/* trx for msg->trx of received msgs */	
+	struct gsm_bts_trx *trx;
+
+	/* msgb queue of to-be-transmitted msgs */
+	struct llist_head tx_list;
+
+	/* SAPI and TEI on the E1 TS */
+	uint8_t sapi;
+	uint8_t tei;
+
+	union {
+		struct {
+			uint8_t channel;
+		} misdn;
+	} driver;
+};
+
+enum e1inp_ts_type {
+	E1INP_TS_TYPE_NONE,
+	E1INP_TS_TYPE_SIGN,
+	E1INP_TS_TYPE_TRAU,
+};
+const char *e1inp_tstype_name(enum e1inp_ts_type tp);
+
+/* A timeslot in the E1 interface */
+struct e1inp_ts {
+	enum e1inp_ts_type type;
+	int num;
+
+	/* to which line do we belong ? */
+	struct e1inp_line *line;
+
+	union {
+		struct {
+			/* list of all signalling links on this TS */
+			struct llist_head sign_links;
+			/* delay for the queue */
+			int delay;
+			/* timer when to dequeue next frame */
+			struct osmo_timer_list tx_timer;
+		} sign;
+		struct {
+			/* subchannel demuxer for frames from E1 */
+			struct subch_demux demux;
+			/* subchannel muxer for frames to E1 */
+			struct subch_mux mux;
+		} trau;
+	};
+	union {
+		struct {
+			/* mISDN driver has one fd for each ts */
+			struct osmo_fd fd;
+		} misdn;
+		struct {
+			/* ip.access driver has one fd for each ts */
+			struct osmo_fd fd;
+		} ipaccess;
+		struct {
+			/* DAHDI driver has one fd for each ts */
+			struct osmo_fd fd;
+			struct lapd_instance *lapd;
+		} dahdi;
+	} driver;
+};
+
+struct gsm_e1_subslot {
+	/* Number of E1 link */
+	uint8_t e1_nr;
+	/* Number of E1 TS inside E1 link */
+	uint8_t e1_ts;
+	/* Sub-slot within the E1 TS, 0xff if full TS */
+	uint8_t e1_ts_ss;
+};
+
+enum e1inp_line_role {
+	E1INP_LINE_R_NONE,
+	E1INP_LINE_R_BSC,
+	E1INP_LINE_R_BTS,
+	E1INP_LINE_R_MAX
+};
+
+struct e1inp_driver {
+	struct llist_head list;
+	const char *name;
+	int (*want_write)(struct e1inp_ts *ts);
+	int (*line_update)(struct e1inp_line *line, enum e1inp_line_role role);
+	int default_delay;
+};
+
+struct e1inp_line {
+	struct llist_head list;
+	int refcnt;
+
+	unsigned int num;
+	const char *name;
+
+	/* array of timestlots */
+	struct e1inp_ts ts[NUM_E1_TS];
+
+	int (*rx)(struct msgb *msg, struct e1inp_ts *ts);
+	int (*rx_err)(int error);
+
+	struct e1inp_driver *driver;
+	void *driver_data;
+};
+
+/* SS_INPUT signals */
+enum signal_input {
+	S_INP_NONE,
+	S_INP_TEI_UP,
+	S_INP_TEI_DN,
+	S_INP_LINE_INIT,
+	S_INP_LINE_ALARM,
+	S_INP_LINE_NOALARM,
+};
+
+/* register a driver with the E1 core */
+int e1inp_driver_register(struct e1inp_driver *drv);
+
+/* fine a previously registered driver */
+struct e1inp_driver *e1inp_driver_find(const char *name);
+
+/* register a line with the E1 core */
+int e1inp_line_register(struct e1inp_line *line);
+
+/* get a line by its ID */
+struct e1inp_line *e1inp_line_get(uint8_t e1_nr);
+
+/* create a line in the E1 input core */
+struct e1inp_line *e1inp_line_create(uint8_t e1_nr, const char *driver_name, int (*rx)(struct msgb *msg, struct e1inp_ts *ts), int (*rx_err)(int error));
+
+/* find a sign_link for given TEI and SAPI in a TS */
+struct e1inp_sign_link *
+e1inp_lookup_sign_link(struct e1inp_ts *ts, uint8_t tei,
+			uint8_t sapi);
+
+/* create a new signalling link in a E1 timeslot */
+struct e1inp_sign_link *
+e1inp_sign_link_create(struct e1inp_ts *ts, enum e1inp_sign_type type,
+			struct gsm_bts_trx *trx, uint8_t tei,
+			uint8_t sapi);
+
+/* configure and initialize one e1inp_ts */
+int e1inp_ts_config_sign(struct e1inp_ts *ts, struct e1inp_line *line);
+int e1inp_ts_config_trau(struct e1inp_ts *ts, struct e1inp_line *line,
+                         int (*subch_cb)(struct subch_demux *dmx, int ch,
+                                         uint8_t *data, int len, void *_priv));
+
+/* Call from the Stack: configuration of this TS has changed */
+int e1inp_update_ts(struct e1inp_ts *ts);
+
+/* Receive a packet from the E1 driver */
+int e1inp_rx_ts(struct e1inp_ts *ts, struct msgb *msg,
+		uint8_t tei, uint8_t sapi);
+
+/* called by driver if it wants to transmit on a given TS */
+struct msgb *e1inp_tx_ts(struct e1inp_ts *e1i_ts,
+			 struct e1inp_sign_link **sign_link);
+
+/* called by driver in case some kind of link state event */
+int e1inp_event(struct e1inp_ts *ts, int evt, uint8_t tei, uint8_t sapi);
+
+/* Write LAPD frames to the fd. */
+void e1_set_pcap_fd(int fd);
+
+/* called by TRAU muxer to obtain the destination mux entity */
+struct subch_mux *e1inp_get_mux(uint8_t e1_nr, uint8_t ts_nr);
+
+void e1inp_sign_link_destroy(struct e1inp_sign_link *link);
+int e1inp_line_update(struct e1inp_line *line, enum e1inp_line_role role);
+
+struct gsm_network;
+int ipaccess_setup(struct gsm_network *gsmnet);
+int hsl_setup(struct gsm_network *gsmnet);
+
+extern struct llist_head e1inp_driver_list;
+extern struct llist_head e1inp_line_list;
+
+int e1inp_vty_init(void);
+void e1inp_init(void);
+
+int _abis_nm_sendmsg(struct msgb *msg, int to_trx_oml);
+
+/* XXX */
+struct input_signal_data {
+	int link_type;
+	uint8_t tei;
+	uint8_t sapi;
+	struct gsm_bts_trx *trx;
+	struct e1inp_line *line;
+};
+
+#endif /* _E1_INPUT_H */