diff --git a/include/osmocom/core/gsmtap_util.h b/include/osmocom/core/gsmtap_util.h
index f553c17..36cbf53 100644
--- a/include/osmocom/core/gsmtap_util.h
+++ b/include/osmocom/core/gsmtap_util.h
@@ -5,46 +5,41 @@
 #include <osmocom/core/write_queue.h>
 #include <osmocom/core/select.h>
 
-/* convert RSL channel number to GSMTAP channel type */
+/*! \defgroup gsmtap GSMTAP
+ *  @{
+ */
+/*! \file gsmtap_util.h */
+
 uint8_t chantype_rsl2gsmtap(uint8_t rsl_chantype, uint8_t rsl_link_id);
 
-/* generate msgb from data + metadata */
 struct msgb *gsmtap_makemsg(uint16_t arfcn, uint8_t ts, uint8_t chan_type,
 			    uint8_t ss, uint32_t fn, int8_t signal_dbm,
 			    uint8_t snr, const uint8_t *data, unsigned int len);
 
-/* one gsmtap instance */
+/*! \brief one gsmtap instance */
 struct gsmtap_inst {
-	int ofd_wq_mode;
-	struct osmo_wqueue wq;
-	struct osmo_fd sink_ofd;
+	int ofd_wq_mode;	/*!< \brief wait queue mode? */
+	struct osmo_wqueue wq;	/*!< \brief the wait queue */
+	struct osmo_fd sink_ofd;/*!< \brief file descriptor */
 };
 
+/*! \brief obtain the file descriptor associated with a gsmtap instance */
 static inline int gsmtap_inst_fd(struct gsmtap_inst *gti)
 {
 	return gti->wq.bfd.fd;
 }
 
-/* Open a GSMTAP source (sending) socket, conncet it to host/port and
- * return resulting fd */
 int gsmtap_source_init_fd(const char *host, uint16_t port);
 
-/* Add a local sink to an existing GSMTAP source and return fd */
 int gsmtap_source_add_sink_fd(int gsmtap_fd);
 
-/* Open GSMTAP source (sending) socket, connect it to host/port,
- * allocate 'struct gsmtap_inst' and optionally osmo_fd/osmo_wqueue
- * registration */
 struct gsmtap_inst *gsmtap_source_init(const char *host, uint16_t port,
 					int ofd_wq_mode);
 
-/* Add a local sink to an existing GSMTAP source instance */
 int gsmtap_source_add_sink(struct gsmtap_inst *gti);
 
-/* Send a msgb through a GSMTAP source */
 int gsmtap_sendmsg(struct gsmtap_inst *gti, struct msgb *msg);
 
-/* generate a message and send it via GSMTAP */
 int gsmtap_send(struct gsmtap_inst *gti, uint16_t arfcn, uint8_t ts,
 		uint8_t chan_type, uint8_t ss, uint32_t fn,
 		int8_t signal_dbm, uint8_t snr, const uint8_t *data,