sfc: nicer log message on PTP probe fail

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sfc/ptp.c

@@ -604,7 +604,12 @@ static int efx_ptp_disable(struct efx_nic *efx)
 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
 				outbuf, sizeof(outbuf), NULL);
 	rc = (rc == -EALREADY) ? 0 : rc;
-	if (rc)
+	/* If we get ENOSYS, the NIC doesn't support PTP, and thus this function
+	 * should only have been called during probe.
+	 */
+	if (rc == -ENOSYS || rc == -EPERM)
+		netif_info(efx, probe, efx->net_dev, "no PTP support\n");
+	else if (rc)
 		efx_mcdi_display_error(efx, MC_CMD_PTP,
 				       MC_CMD_PTP_IN_DISABLE_LEN,
 				       outbuf, sizeof(outbuf), rc);