diff --git a/subsys/net/lib/zperf/zperf_common.c b/subsys/net/lib/zperf/zperf_common.c
index 89224b6..3c39008 100644
--- a/subsys/net/lib/zperf/zperf_common.c
+++ b/subsys/net/lib/zperf/zperf_common.c
@@ -109,7 +109,7 @@
 	return 0;
 }
 
-int zperf_prepare_upload_sock(const struct sockaddr *peer_addr, int tos,
+int zperf_prepare_upload_sock(const struct sockaddr *peer_addr, uint8_t tos,
 			      int priority, int proto)
 {
 	socklen_t addrlen = peer_addr->sa_family == AF_INET6 ?
diff --git a/subsys/net/lib/zperf/zperf_internal.h b/subsys/net/lib/zperf/zperf_internal.h
index b8cdb84..8450674 100644
--- a/subsys/net/lib/zperf/zperf_internal.h
+++ b/subsys/net/lib/zperf/zperf_internal.h
@@ -95,7 +95,7 @@
 
 extern void connect_ap(char *ssid);
 
-int zperf_prepare_upload_sock(const struct sockaddr *peer_addr, int tos,
+int zperf_prepare_upload_sock(const struct sockaddr *peer_addr, uint8_t tos,
 			      int priority, int proto);
 
 uint32_t zperf_packet_duration(uint32_t packet_size, uint32_t rate_in_kbps);