net: phy: micrel: add ksz9477_get_features()

KSZ8563R, which has same PHYID as KSZ9477 family, will change "EEE control
and capability 1" (Register 3.20) content depending on configuration of
"EEE advertisement 1" (Register 7.60). Changes on the 7.60 will affect
3.20 register.

So, instead of depending on register 3.20, driver should set supported_eee.

Proper supported_eee configuration is needed to make use of generic
PHY c45 set/get_eee functions provided by next patches.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/micrel.c

@@ -1392,6 +1392,26 @@ static int ksz9131_config_aneg(struct phy_device *phydev)
 	return genphy_config_aneg(phydev);
 }
 
+static int ksz9477_get_features(struct phy_device *phydev)
+{
+	int ret;
+
+	ret = genphy_read_abilities(phydev);
+	if (ret)
+		return ret;
+
+	/* The "EEE control and capability 1" (Register 3.20) seems to be
+	 * influenced by the "EEE advertisement 1" (Register 7.60). Changes
+	 * on the 7.60 will affect 3.20. So, we need to construct our own list
+	 * of caps.
+	 * KSZ8563R should have 100BaseTX/Full only.
+	 */
+	linkmode_and(phydev->supported_eee, phydev->supported,
+		     PHY_EEE_CAP1_FEATURES);
+
+	return 0;
+}
+
 #define KSZ8873MLL_GLOBAL_CONTROL_4	0x06
 #define KSZ8873MLL_GLOBAL_CONTROL_4_DUPLEX	BIT(6)
 #define KSZ8873MLL_GLOBAL_CONTROL_4_SPEED	BIT(4)
@@ -4172,6 +4192,7 @@ static struct phy_driver ksphy_driver[] = {
 	.handle_interrupt = kszphy_handle_interrupt,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,
+	.get_features	= ksz9477_get_features,
 } };
 
 module_phy_driver(ksphy_driver);