---
 sk.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sk.c b/sk.c
index 19395c9..6e0b1d2 100644
--- a/sk.c
+++ b/sk.c
@@ -56,6 +56,10 @@ static void init_ifreq(struct ifreq *ifreq, struct hwtstamp_config *cfg,
 	ifreq->ifr_data = (void *) cfg;
 }
 
+#ifndef HWTSTAMP_TX_ONESTEP_SYNC
+#define HWTSTAMP_TX_ONESTEP_SYNC HWTSTAMP_TX_ON
+#endif
+
 static int hwts_init(int fd, const char *device, int rx_filter,
 	int rx_filter2, int tx_type)
 {
-- 
2.34.1