net: phy: adin: configure RGMII/RMII/MII modes on config

The ADIN1300 chip supports RGMII, RMII & MII modes. Default (if
unconfigured) is RGMII.
This change adds support for configuring these modes via the device
registers.

For RGMII with internal delays (modes RGMII_ID,RGMII_TXID, RGMII_RXID),
the default delay is 2 ns. This can be configurable and will be done in
a subsequent change.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/adin.c

@@ -31,9 +31,86 @@
 	(ADIN1300_INT_LINK_STAT_CHNG_EN | ADIN1300_INT_HW_IRQ_EN)
 #define ADIN1300_INT_STATUS_REG			0x0019
 
+#define ADIN1300_GE_RGMII_CFG_REG		0xff23
+#define   ADIN1300_GE_RGMII_RXID_EN		BIT(2)
+#define   ADIN1300_GE_RGMII_TXID_EN		BIT(1)
+#define   ADIN1300_GE_RGMII_EN			BIT(0)
+
+#define ADIN1300_GE_RMII_CFG_REG		0xff24
+#define   ADIN1300_GE_RMII_EN			BIT(0)
+
+static int adin_config_rgmii_mode(struct phy_device *phydev)
+{
+	int reg;
+
+	if (!phy_interface_is_rgmii(phydev))
+		return phy_clear_bits_mmd(phydev, MDIO_MMD_VEND1,
+					  ADIN1300_GE_RGMII_CFG_REG,
+					  ADIN1300_GE_RGMII_EN);
+
+	reg = phy_read_mmd(phydev, MDIO_MMD_VEND1, ADIN1300_GE_RGMII_CFG_REG);
+	if (reg < 0)
+		return reg;
+
+	reg |= ADIN1300_GE_RGMII_EN;
+
+	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
+	    phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID) {
+		reg |= ADIN1300_GE_RGMII_RXID_EN;
+	} else {
+		reg &= ~ADIN1300_GE_RGMII_RXID_EN;
+	}
+
+	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
+	    phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID) {
+		reg |= ADIN1300_GE_RGMII_TXID_EN;
+	} else {
+		reg &= ~ADIN1300_GE_RGMII_TXID_EN;
+	}
+
+	return phy_write_mmd(phydev, MDIO_MMD_VEND1,
+			     ADIN1300_GE_RGMII_CFG_REG, reg);
+}
+
+static int adin_config_rmii_mode(struct phy_device *phydev)
+{
+	int reg;
+
+	if (phydev->interface != PHY_INTERFACE_MODE_RMII)
+		return phy_clear_bits_mmd(phydev, MDIO_MMD_VEND1,
+					  ADIN1300_GE_RMII_CFG_REG,
+					  ADIN1300_GE_RMII_EN);
+
+	reg = phy_read_mmd(phydev, MDIO_MMD_VEND1, ADIN1300_GE_RMII_CFG_REG);
+	if (reg < 0)
+		return reg;
+
+	reg |= ADIN1300_GE_RMII_EN;
+
+	return phy_write_mmd(phydev, MDIO_MMD_VEND1,
+			     ADIN1300_GE_RMII_CFG_REG, reg);
+}
+
 static int adin_config_init(struct phy_device *phydev)
 {
-	return genphy_config_init(phydev);
+	int rc;
+
+	rc = genphy_config_init(phydev);
+	if (rc < 0)
+		return rc;
+
+	rc = adin_config_rgmii_mode(phydev);
+	if (rc < 0)
+		return rc;
+
+	rc = adin_config_rmii_mode(phydev);
+	if (rc < 0)
+		return rc;
+
+	phydev_dbg(phydev, "PHY is using mode '%s'\n",
+		   phy_modes(phydev->interface));
+
+	return 0;
 }
 
 static int adin_phy_ack_intr(struct phy_device *phydev)