[PATCH net-next 1/2] net: phy: use phy_id_mask value zero for exact match

[Heiner Kallweit <hkallweit1@gmail.com>]

A phy_id_mask value zero means every PHYID matches, therefore
value zero isn't used. So we can safely redefine the semantics
of value zero to mean "exact match". This allows to avoid some
boilerplate code in PHY driver configs.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/phy/phy_device.c | 21 +++++++++++++++------
 include/linux/phy.h          |  2 +-
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index ab33d1777..d165a2c82 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -483,15 +483,24 @@ static int phy_bus_match(struct device *dev, struct device_driver *drv)
 			if (!(phydev->c45_ids.devices_in_package & (1 << i)))
 				continue;
 
-			if ((phydrv->phy_id & phydrv->phy_id_mask) ==
-			    (phydev->c45_ids.device_ids[i] &
-			     phydrv->phy_id_mask))
-				return 1;
+			if (!phydrv->phy_id_mask) {
+				if (phydrv->phy_id ==
+				    phydev->c45_ids.device_ids[i])
+					return 1;
+			} else {
+				if ((phydrv->phy_id & phydrv->phy_id_mask) ==
+				    (phydev->c45_ids.device_ids[i] &
+				     phydrv->phy_id_mask))
+					return 1;
+			}
 		}
 		return 0;
 	} else {
-		return (phydrv->phy_id & phydrv->phy_id_mask) ==
-			(phydev->phy_id & phydrv->phy_id_mask);
+		if (!phydrv->phy_id_mask)
+			return phydrv->phy_id == phydev->phy_id;
+		else
+			return (phydrv->phy_id & phydrv->phy_id_mask) ==
+			       (phydev->phy_id & phydrv->phy_id_mask);
 	}
 }
 
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 2090277ea..e30ca2fdd 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -500,7 +500,7 @@ struct phy_driver {
 	struct mdio_driver_common mdiodrv;
 	u32 phy_id;
 	char *name;
-	u32 phy_id_mask;
+	u32 phy_id_mask; /* value 0 means exact match */
 	const unsigned long * const features;
 	u32 flags;
 	const void *driver_data;
-- 
2.19.1