net: ethernet: Add helper to determine if pause configuration is supported

Rather than have MAC drivers open code the test, add a helper in
phylib. This will help when we change the type of phydev->supported.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/apm/xgene/xgene_enet_ethtool.c

@@ -312,9 +312,7 @@ static int xgene_set_pauseparam(struct net_device *ndev,
 		if (!phydev)
 			return -EINVAL;
 
-		if (!(phydev->supported & SUPPORTED_Pause) ||
-		    (!(phydev->supported & SUPPORTED_Asym_Pause) &&
-		     pp->rx_pause != pp->tx_pause))
+		if (!phy_validate_pause(phydev, pp))
 			return -EINVAL;
 
 		pdata->pause_autoneg = pp->autoneg;

drivers/net/ethernet/broadcom/tg3.c

@@ -12496,9 +12496,7 @@ static int tg3_set_pauseparam(struct net_device *dev, struct ethtool_pauseparam
 
 		phydev = mdiobus_get_phy(tp->mdio_bus, tp->phy_addr);
 
-		if (!(phydev->supported & SUPPORTED_Pause) ||
-		    (!(phydev->supported & SUPPORTED_Asym_Pause) &&
-		     (epause->rx_pause != epause->tx_pause)))
+		if (!phy_validate_pause(phydev, epause))
 			return -EINVAL;
 
 		tp->link_config.flowctrl = 0;

drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c

@@ -194,9 +194,7 @@ static int dpaa_set_pauseparam(struct net_device *net_dev,
 		return -ENODEV;
 	}
 
-	if (!(phydev->supported & SUPPORTED_Pause) ||
-	    (!(phydev->supported & SUPPORTED_Asym_Pause) &&
-	    (epause->rx_pause != epause->tx_pause)))
+	if (!phy_validate_pause(phydev, epause))
 		return -EINVAL;
 
 	/* The MAC should know how to handle PAUSE frame autonegotiation before

drivers/net/ethernet/freescale/gianfar_ethtool.c

@@ -507,9 +507,7 @@ static int gfar_spauseparam(struct net_device *dev,
 	if (!phydev)
 		return -ENODEV;
 
-	if (!(phydev->supported & SUPPORTED_Pause) ||
-	    (!(phydev->supported & SUPPORTED_Asym_Pause) &&
-	     (epause->rx_pause != epause->tx_pause)))
+	if (!phy_validate_pause(phydev, epause))
 		return -EINVAL;
 
 	priv->rx_pause_en = priv->tx_pause_en = 0;

drivers/net/phy/phy_device.c

@@ -1863,6 +1863,26 @@ void phy_set_asym_pause(struct phy_device *phydev, bool rx, bool tx)
 }
 EXPORT_SYMBOL(phy_set_asym_pause);
 
+/**
+ * phy_validate_pause - Test if the PHY/MAC support the pause configuration
+ * @phydev: phy_device struct
+ * @pp: requested pause configuration
+ *
+ * Description: Test if the PHY/MAC combination supports the Pause
+ * configuration the user is requesting. Returns True if it is
+ * supported, false otherwise.
+ */
+bool phy_validate_pause(struct phy_device *phydev,
+			struct ethtool_pauseparam *pp)
+{
+	if (!(phydev->supported & SUPPORTED_Pause) ||
+	    (!(phydev->supported & SUPPORTED_Asym_Pause) &&
+	     pp->rx_pause != pp->tx_pause))
+		return false;
+	return true;
+}
+EXPORT_SYMBOL(phy_validate_pause);
+
 static void of_set_phy_supported(struct phy_device *phydev)
 {
 	struct device_node *node = phydev->mdio.dev.of_node;

include/linux/phy.h

@@ -1055,6 +1055,8 @@ void phy_support_asym_pause(struct phy_device *phydev);
 void phy_set_sym_pause(struct phy_device *phydev, bool rx, bool tx,
 		       bool autoneg);
 void phy_set_asym_pause(struct phy_device *phydev, bool rx, bool tx);
+bool phy_validate_pause(struct phy_device *phydev,
+			struct ethtool_pauseparam *pp);
 
 int phy_register_fixup(const char *bus_id, u32 phy_uid, u32 phy_uid_mask,
 		       int (*run)(struct phy_device *));