Merge branch 'net-phy-Add-general-dummy-stubs-for-MMD-register-access'

Kevin Hao says:

====================
net: phy: Add general dummy stubs for MMD register access

v2:
As suggested by Andrew:
  - Add general dummy stubs
  - Also use that for the micrel phy

This patch series fix the Ethernet broken on the mpc8315erdb board introduced
by commit b6b5e8a69118 ("gianfar: Disable EEE autoneg by default").
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/micrel.c

@@ -635,25 +635,6 @@ static int ksz8873mll_config_aneg(struct phy_device *phydev)
 	return 0;
 }
 
-/* This routine returns -1 as an indication to the caller that the
- * Micrel ksz9021 10/100/1000 PHY does not support standard IEEE
- * MMD extended PHY registers.
- */
-static int
-ksz9021_rd_mmd_phyreg(struct phy_device *phydev, int devad, u16 regnum)
-{
-	return -1;
-}
-
-/* This routine does nothing since the Micrel ksz9021 does not support
- * standard IEEE MMD extended PHY registers.
- */
-static int
-ksz9021_wr_mmd_phyreg(struct phy_device *phydev, int devad, u16 regnum, u16 val)
-{
-	return -1;
-}
-
 static int kszphy_get_sset_count(struct phy_device *phydev)
 {
 	return ARRAY_SIZE(kszphy_hw_stats);
@@ -946,8 +927,8 @@ static struct phy_driver ksphy_driver[] = {
 	.get_stats	= kszphy_get_stats,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,
-	.read_mmd	= ksz9021_rd_mmd_phyreg,
-	.write_mmd	= ksz9021_wr_mmd_phyreg,
+	.read_mmd	= genphy_read_mmd_unsupported,
+	.write_mmd	= genphy_write_mmd_unsupported,
 }, {
 	.phy_id		= PHY_ID_KSZ9031,
 	.phy_id_mask	= MICREL_PHY_ID_MASK,

drivers/net/phy/phy_device.c

@@ -1673,6 +1673,23 @@ int genphy_config_init(struct phy_device *phydev)
 }
 EXPORT_SYMBOL(genphy_config_init);
 
+/* This is used for the phy device which doesn't support the MMD extended
+ * register access, but it does have side effect when we are trying to access
+ * the MMD register via indirect method.
+ */
+int genphy_read_mmd_unsupported(struct phy_device *phdev, int devad, u16 regnum)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(genphy_read_mmd_unsupported);
+
+int genphy_write_mmd_unsupported(struct phy_device *phdev, int devnum,
+				 u16 regnum, u16 val)
+{
+	return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(genphy_write_mmd_unsupported);
+
 int genphy_suspend(struct phy_device *phydev)
 {
 	return phy_set_bits(phydev, MII_BMCR, BMCR_PDOWN);

drivers/net/phy/realtek.c

@@ -172,6 +172,8 @@ static struct phy_driver realtek_drvs[] = {
 		.flags		= PHY_HAS_INTERRUPT,
 		.ack_interrupt	= &rtl821x_ack_interrupt,
 		.config_intr	= &rtl8211b_config_intr,
+		.read_mmd	= &genphy_read_mmd_unsupported,
+		.write_mmd	= &genphy_write_mmd_unsupported,
 	}, {
 		.phy_id		= 0x001cc914,
 		.name		= "RTL8211DN Gigabit Ethernet",

include/linux/phy.h

@@ -984,6 +984,10 @@ static inline int genphy_no_soft_reset(struct phy_device *phydev)
 {
 	return 0;
 }
+int genphy_read_mmd_unsupported(struct phy_device *phdev, int devad,
+				u16 regnum);
+int genphy_write_mmd_unsupported(struct phy_device *phdev, int devnum,
+				 u16 regnum, u16 val);
 
 /* Clause 45 PHY */
 int genphy_c45_restart_aneg(struct phy_device *phydev);