net: stmmac: dwmac-qcom-ethqos: prepare the driver for more PHY modes

In preparation for supporting SGMII, let's make the code a bit more
generic. Add a new callback for MAC configuration so that we can assign
a different variant of it in the future.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c

@@ -92,11 +92,13 @@ struct ethqos_emac_driver_data {
 struct qcom_ethqos {
 	struct platform_device *pdev;
 	void __iomem *rgmii_base;
+	int (*configure_func)(struct qcom_ethqos *ethqos);
 
 	unsigned int link_clk_rate;
 	struct clk *link_clk;
 	struct phy *serdes_phy;
 	unsigned int speed;
+	int phy_mode;
 
 	const struct ethqos_emac_por *por;
 	unsigned int num_por;
@@ -331,13 +333,11 @@ static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
 {
 	struct device *dev = &ethqos->pdev->dev;
 	int phase_shift;
-	int phy_mode;
 	int loopback;
 
 	/* Determine if the PHY adds a 2 ns TX delay or the MAC handles it */
-	phy_mode = device_get_phy_mode(dev);
-	if (phy_mode == PHY_INTERFACE_MODE_RGMII_ID ||
-	    phy_mode == PHY_INTERFACE_MODE_RGMII_TXID)
+	if (ethqos->phy_mode == PHY_INTERFACE_MODE_RGMII_ID ||
+	    ethqos->phy_mode == PHY_INTERFACE_MODE_RGMII_TXID)
 		phase_shift = 0;
 	else
 		phase_shift = RGMII_CONFIG2_TX_CLK_PHASE_SHIFT_EN;
@@ -483,7 +483,7 @@ static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
 	return 0;
 }
 
-static int ethqos_configure(struct qcom_ethqos *ethqos)
+static int ethqos_configure_rgmii(struct qcom_ethqos *ethqos)
 {
 	struct device *dev = &ethqos->pdev->dev;
 	volatile unsigned int dll_lock;
@@ -559,6 +559,11 @@ static int ethqos_configure(struct qcom_ethqos *ethqos)
 	return 0;
 }
 
+static int ethqos_configure(struct qcom_ethqos *ethqos)
+{
+	return ethqos->configure_func(ethqos);
+}
+
 static void ethqos_fix_mac_speed(void *priv, unsigned int speed)
 {
 	struct qcom_ethqos *ethqos = priv;
@@ -650,6 +655,22 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
 		goto out_config_dt;
 	}
 
+	ethqos->phy_mode = device_get_phy_mode(dev);
+	switch (ethqos->phy_mode) {
+	case PHY_INTERFACE_MODE_RGMII:
+	case PHY_INTERFACE_MODE_RGMII_ID:
+	case PHY_INTERFACE_MODE_RGMII_RXID:
+	case PHY_INTERFACE_MODE_RGMII_TXID:
+		ethqos->configure_func = ethqos_configure_rgmii;
+		break;
+	case -ENODEV:
+		ret = -ENODEV;
+		goto out_config_dt;
+	default:
+		ret = -EINVAL;
+		goto out_config_dt;
+	}
+
 	ethqos->pdev = pdev;
 	ethqos->rgmii_base = devm_platform_ioremap_resource_byname(pdev, "rgmii");
 	if (IS_ERR(ethqos->rgmii_base)) {