diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index 6ff123da6a14..b3b2a00b620d 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -834,6 +834,9 @@ struct gem_tx_ts {
 /* limit RX checksum offload to TCP and UDP packets */
 #define GEM_RX_CSUM_CHECKED_MASK		2
 
+/* Scaled PPM fraction */
+#define PPM_FRACTION	16
+
 /* struct macb_tx_skb - data about an skb which is being transmitted
  * @skb: skb currently being transmitted, only set for the last buffer
  *       of the frame
diff --git a/drivers/net/ethernet/cadence/macb_ptp.c b/drivers/net/ethernet/cadence/macb_ptp.c
index 0a8aca8d3634..6276eac8056b 100644
--- a/drivers/net/ethernet/cadence/macb_ptp.c
+++ b/drivers/net/ethernet/cadence/macb_ptp.c
@@ -135,7 +135,7 @@ static int gem_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
 	 * (temp / USEC_PER_SEC) + 0.5
 	 */
 	adj += (USEC_PER_SEC >> 1);
-	adj >>= GEM_SUBNSINCR_SIZE; /* remove fractions */
+	adj >>= PPM_FRACTION; /* remove fractions */
 	adj = div_u64(adj, USEC_PER_SEC);
 	adj = neg_adj ? (word - adj) : (word + adj);