net: ethernet: mtk-star-emac: add support for MII interface

Add support for MII interface.
If user wants to use MII, assign "MII" to "phy-mode" property in dts.
Signed-off-by: Biao Huang <biao.huang@mediatek.com>
Signed-off-by: Yinghua Pan <ot_yinghua.pan@mediatek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mediatek/mtk_star_emac.c

@@ -192,6 +192,7 @@ static const char *const mtk_star_clk_names[] = { "core", "reg", "trans" };
 #define MTK_PERICFG_REG_NIC_CFG1_CON		0x03c8
 #define MTK_PERICFG_REG_NIC_CFG_CON_V2		0x0c10
 #define MTK_PERICFG_REG_NIC_CFG_CON_CFG_INTF	GENMASK(3, 0)
+#define MTK_PERICFG_BIT_NIC_CFG_CON_MII		0
 #define MTK_PERICFG_BIT_NIC_CFG_CON_RMII	1
 #define MTK_PERICFG_BIT_NIC_CFG_CON_CLK		BIT(0)
 #define MTK_PERICFG_BIT_NIC_CFG_CON_CLK_V2	BIT(8)
@@ -1462,6 +1463,7 @@ static int mtk_star_set_timing(struct mtk_star_priv *priv)
 	unsigned int delay_val = 0;
 
 	switch (priv->phy_intf) {
+	case PHY_INTERFACE_MODE_MII:
 	case PHY_INTERFACE_MODE_RMII:
 		delay_val |= FIELD_PREP(MTK_STAR_BIT_INV_RX_CLK, priv->rx_inv);
 		delay_val |= FIELD_PREP(MTK_STAR_BIT_INV_TX_CLK, priv->tx_inv);
@@ -1543,7 +1545,8 @@ static int mtk_star_probe(struct platform_device *pdev)
 	ret = of_get_phy_mode(of_node, &priv->phy_intf);
 	if (ret) {
 		return ret;
-	} else if (priv->phy_intf != PHY_INTERFACE_MODE_RMII) {
+	} else if (priv->phy_intf != PHY_INTERFACE_MODE_RMII &&
+		   priv->phy_intf != PHY_INTERFACE_MODE_MII) {
 		dev_err(dev, "unsupported phy mode: %s\n",
 			phy_modes(priv->phy_intf));
 		return -EINVAL;
@@ -1612,6 +1615,10 @@ static int mt8516_set_interface_mode(struct net_device *ndev)
 	unsigned int intf_val, ret, rmii_rxc;
 
 	switch (priv->phy_intf) {
+	case PHY_INTERFACE_MODE_MII:
+		intf_val = MTK_PERICFG_BIT_NIC_CFG_CON_MII;
+		rmii_rxc = 0;
+		break;
 	case PHY_INTERFACE_MODE_RMII:
 		intf_val = MTK_PERICFG_BIT_NIC_CFG_CON_RMII;
 		rmii_rxc = priv->rmii_rxc ? 0 : MTK_PERICFG_BIT_NIC_CFG_CON_CLK;
@@ -1641,6 +1648,9 @@ static int mt8365_set_interface_mode(struct net_device *ndev)
 	unsigned int intf_val;
 
 	switch (priv->phy_intf) {
+	case PHY_INTERFACE_MODE_MII:
+		intf_val = MTK_PERICFG_BIT_NIC_CFG_CON_MII;
+		break;
 	case PHY_INTERFACE_MODE_RMII:
 		intf_val = MTK_PERICFG_BIT_NIC_CFG_CON_RMII;
 		intf_val |= priv->rmii_rxc ? 0 : MTK_PERICFG_BIT_NIC_CFG_CON_CLK_V2;