net: phy: tja11xx: add support for master-slave configuration

The TJA11xx PHYs have a vendor specific Master/Slave configuration bit,
which is not compatible with IEEE 803.2-2018 spec for 100Base-T1
devices. So, provide a custom config_ange call back to solve this
problem.
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/nxp-tja11xx.c

@@ -30,6 +30,7 @@
 #define MII_ECTRL_WAKE_REQUEST		BIT(0)
 
 #define MII_CFG1			18
+#define MII_CFG1_MASTER_SLAVE		BIT(15)
 #define MII_CFG1_AUTO_OP		BIT(14)
 #define MII_CFG1_SLEEP_CONFIRM		BIT(6)
 #define MII_CFG1_LED_MODE_MASK		GENMASK(5, 4)
@@ -167,6 +168,32 @@ static int tja11xx_soft_reset(struct phy_device *phydev)
 	return genphy_soft_reset(phydev);
 }
 
+static int tja11xx_config_aneg(struct phy_device *phydev)
+{
+	u16 ctl = 0;
+	int ret;
+
+	switch (phydev->master_slave_set) {
+	case MASTER_SLAVE_CFG_MASTER_FORCE:
+		ctl |= MII_CFG1_MASTER_SLAVE;
+		break;
+	case MASTER_SLAVE_CFG_SLAVE_FORCE:
+		break;
+	case MASTER_SLAVE_CFG_UNKNOWN:
+	case MASTER_SLAVE_CFG_UNSUPPORTED:
+		return 0;
+	default:
+		phydev_warn(phydev, "Unsupported Master/Slave mode\n");
+		return -ENOTSUPP;
+	}
+
+	ret = phy_modify_changed(phydev, MII_CFG1, MII_CFG1_MASTER_SLAVE, ctl);
+	if (ret < 0)
+		return ret;
+
+	return __genphy_config_aneg(phydev, ret);
+}
+
 static int tja11xx_config_init(struct phy_device *phydev)
 {
 	int ret;
@@ -224,10 +251,22 @@ static int tja11xx_read_status(struct phy_device *phydev)
 {
 	int ret;
 
+	phydev->master_slave_get = MASTER_SLAVE_CFG_UNKNOWN;
+	phydev->master_slave_state = MASTER_SLAVE_STATE_UNSUPPORTED;
+
 	ret = genphy_update_link(phydev);
 	if (ret)
 		return ret;
 
+	ret = phy_read(phydev, MII_CFG1);
+	if (ret < 0)
+		return ret;
+
+	if (ret & MII_CFG1_MASTER_SLAVE)
+		phydev->master_slave_get = MASTER_SLAVE_CFG_MASTER_FORCE;
+	else
+		phydev->master_slave_get = MASTER_SLAVE_CFG_SLAVE_FORCE;
+
 	if (phydev->link) {
 		ret = phy_read(phydev, MII_COMMSTAT);
 		if (ret < 0)
@@ -504,6 +543,7 @@ static struct phy_driver tja11xx_driver[] = {
 		.features       = PHY_BASIC_T1_FEATURES,
 		.probe		= tja11xx_probe,
 		.soft_reset	= tja11xx_soft_reset,
+		.config_aneg	= tja11xx_config_aneg,
 		.config_init	= tja11xx_config_init,
 		.read_status	= tja11xx_read_status,
 		.suspend	= genphy_suspend,
@@ -519,6 +559,7 @@ static struct phy_driver tja11xx_driver[] = {
 		.features       = PHY_BASIC_T1_FEATURES,
 		.probe		= tja11xx_probe,
 		.soft_reset	= tja11xx_soft_reset,
+		.config_aneg	= tja11xx_config_aneg,
 		.config_init	= tja11xx_config_init,
 		.read_status	= tja11xx_read_status,
 		.suspend	= genphy_suspend,
@@ -533,6 +574,7 @@ static struct phy_driver tja11xx_driver[] = {
 		.features       = PHY_BASIC_T1_FEATURES,
 		.probe		= tja1102_p0_probe,
 		.soft_reset	= tja11xx_soft_reset,
+		.config_aneg	= tja11xx_config_aneg,
 		.config_init	= tja11xx_config_init,
 		.read_status	= tja11xx_read_status,
 		.match_phy_device = tja1102_p0_match_phy_device,
@@ -551,6 +593,7 @@ static struct phy_driver tja11xx_driver[] = {
 		.features       = PHY_BASIC_T1_FEATURES,
 		/* currently no probe for Port 1 is need */
 		.soft_reset	= tja11xx_soft_reset,
+		.config_aneg	= tja11xx_config_aneg,
 		.config_init	= tja11xx_config_init,
 		.read_status	= tja11xx_read_status,
 		.match_phy_device = tja1102_p1_match_phy_device,