diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index ac48a1db99797..39d85e47422ed 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1760,6 +1760,35 @@ static void phylink_phy_change(struct phy_device *phydev, bool up)
 		    phylink_pause_to_str(pl->phy_state.pause));
 }
 
+static int phylink_validate_phy(struct phylink *pl, struct phy_device *phy,
+				unsigned long *supported,
+				struct phylink_link_state *state)
+{
+	/* Check whether we would use rate matching for the proposed interface
+	 * mode.
+	 */
+	state->rate_matching = phy_get_rate_matching(phy, state->interface);
+
+	/* Clause 45 PHYs may switch their Serdes lane between, e.g. 10GBASE-R,
+	 * 5GBASE-R, 2500BASE-X and SGMII if they are not using rate matching.
+	 * For some interface modes (e.g. RXAUI, XAUI and USXGMII) switching
+	 * their Serdes is either unnecessary or not reasonable.
+	 *
+	 * For these which switch interface modes, we really need to know which
+	 * interface modes the PHY supports to properly work out which ethtool
+	 * linkmodes can be supported. For now, as a work-around, we validate
+	 * against all interface modes, which may lead to more ethtool link
+	 * modes being advertised than are actually supported.
+	 */
+	if (phy->is_c45 && state->rate_matching == RATE_MATCH_NONE &&
+	    state->interface != PHY_INTERFACE_MODE_RXAUI &&
+	    state->interface != PHY_INTERFACE_MODE_XAUI &&
+	    state->interface != PHY_INTERFACE_MODE_USXGMII)
+		state->interface = PHY_INTERFACE_MODE_NA;
+
+	return phylink_validate(pl, supported, state);
+}
+
 static int phylink_bringup_phy(struct phylink *pl, struct phy_device *phy,
 			       phy_interface_t interface)
 {
@@ -1780,32 +1809,9 @@ static int phylink_bringup_phy(struct phylink *pl, struct phy_device *phy,
 	memset(&config, 0, sizeof(config));
 	linkmode_copy(supported, phy->supported);
 	linkmode_copy(config.advertising, phy->advertising);
+	config.interface = interface;
 
-	/* Check whether we would use rate matching for the proposed interface
-	 * mode.
-	 */
-	config.rate_matching = phy_get_rate_matching(phy, interface);
-
-	/* Clause 45 PHYs may switch their Serdes lane between, e.g. 10GBASE-R,
-	 * 5GBASE-R, 2500BASE-X and SGMII if they are not using rate matching.
-	 * For some interface modes (e.g. RXAUI, XAUI and USXGMII) switching
-	 * their Serdes is either unnecessary or not reasonable.
-	 *
-	 * For these which switch interface modes, we really need to know which
-	 * interface modes the PHY supports to properly work out which ethtool
-	 * linkmodes can be supported. For now, as a work-around, we validate
-	 * against all interface modes, which may lead to more ethtool link
-	 * modes being advertised than are actually supported.
-	 */
-	if (phy->is_c45 && config.rate_matching == RATE_MATCH_NONE &&
-	    interface != PHY_INTERFACE_MODE_RXAUI &&
-	    interface != PHY_INTERFACE_MODE_XAUI &&
-	    interface != PHY_INTERFACE_MODE_USXGMII)
-		config.interface = PHY_INTERFACE_MODE_NA;
-	else
-		config.interface = interface;
-
-	ret = phylink_validate(pl, supported, &config);
+	ret = phylink_validate_phy(pl, phy, supported, &config);
 	if (ret) {
 		phylink_warn(pl, "validation of %s with support %*pb and advertisement %*pb failed: %pe\n",
 			     phy_modes(config.interface),