Re: [PATCH] net/phy/vitesse: Configure RGMII skew on VSC8601, if needed

From: Alexandru Gagniuc <redacted>
Date: Sat, 12 Nov 2016 15:32:13 -0800

+	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID)
+		ret = vsc8601_add_skew(phydev);

I think you should use phy_interface_is_rgmii() here.