diff --git a/core/net/mac/tsch/tsch-packet.c b/core/net/mac/tsch/tsch-packet.c
index b0ee33535..49f954954 100644
--- a/core/net/mac/tsch/tsch-packet.c
+++ b/core/net/mac/tsch/tsch-packet.c
@@ -66,7 +66,7 @@
 /* Construct enhanced ACK packet and return ACK length */
 int
 tsch_packet_create_eack(uint8_t *buf, int buf_size,
-    linkaddr_t *dest_addr, uint8_t seqno, int16_t drift, int nack)
+    const linkaddr_t *dest_addr, uint8_t seqno, int16_t drift, int nack)
 {
   int ret;
   uint8_t curr_len = 0;
diff --git a/core/net/mac/tsch/tsch-packet.h b/core/net/mac/tsch/tsch-packet.h
index e974230e5..4707b2543 100644
--- a/core/net/mac/tsch/tsch-packet.h
+++ b/core/net/mac/tsch/tsch-packet.h
@@ -88,7 +88,7 @@ by default, useful in case of duplicate seqno */
 
 /* Construct enhanced ACK packet and return ACK length */
 int tsch_packet_create_eack(uint8_t *buf, int buf_size,
-    linkaddr_t *dest_addr, uint8_t seqno, int16_t drift, int nack);
+    const linkaddr_t *dest_addr, uint8_t seqno, int16_t drift, int nack);
 /* Parse enhanced ACK packet, extract drift and nack */
 int tsch_packet_parse_eack(const uint8_t *buf, int buf_size,
     uint8_t seqno, frame802154_t *frame, struct ieee802154_ies *ies, uint8_t *hdr_len);