Re: [PATCH net-next] net: phy: intel-xway: Add RGMII internal delay configuration

+	/* RX delay *must* be specified if internal delay of RX is used. */
+	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
+	    phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID) {
+		rx_int_delay = phy_get_internal_delay(phydev, dev,
+						      &xway_internal_delay[0],
+						      delay_size, true);
+
+		if (rx_int_delay < 0) {
+			phydev_err(phydev, "rx-internal-delay-ps must be specified\n");
+			return rx_int_delay;
+		}
+
+		val &= ~XWAY_MDIO_MIICTRL_RXSKEW_MASK;
+		val |= rx_int_delay << XWAY_MDIO_MIICTRL_RXSKEW_SHIFT;
+	}

Please don't force the delay property to be present, use the default
of 2ns if it is missing.

+	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
+	    phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID ||
+	    phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID)
+		err = phy_write(phydev, XWAY_MDIO_MIICTRL, val);
+

This is the tricky bit. Do we want to act on PHY_INTERFACE_MODE_RGMII?
At the moment, i would say no, lets see how many patches we get
because of the warning you add. But i think it is worth adding a
comment here, briefly explaining why it is missing.

	Andrew