kernel: rtl8366_smi: explicitly set phy addr for switch

By default rtl8366_smi use phy addr 0 at mii-bus to access switch registers.
This patch allow to set it explicitly in dts-file:

	rtl8367 {
		compatible = "realtek,rtl8367b";
		phy-id = <29>; /* switch address at mii-bus */
		realtek,extif2 = <1 0 1 1 1 1 1 1 2>;
		mii-bus = <&mdio>;
		cpu-port = <7>;
	}

Use default 0 address if not set.
Backward compatibility tested on tplink archer c2 v1 (rtl8367rb switch)

Signed-off-by: Serge Vasilugin <[email protected]>
[code style fixes, add explicit phy_id assignment in probe_plat, use
phy-id instead of phy_id for of property name]
Signed-off-by: Chuanhong Guo <[email protected]>
[rebase]
Signed-off-by: Gaspare Bruno <[email protected]>
[added phy_id to struct rtl8366_smi]
Signed-off-by: Mieczyslaw Nalewaj <[email protected]>

target/linux/generic/files/drivers/net/phy/rtl8366_smi.c

@@ -256,7 +256,7 @@ static int __rtl8366_smi_read_reg(struct rtl8366_smi *smi, u32 addr, u32 *data)
 
 int __rtl8366_mdio_read_reg(struct rtl8366_smi *smi, u32 addr, u32 *data)
 {
-	u32 phy_id = MDC_REALTEK_PHY_ADDR;
+	u32 phy_id = smi->phy_id;
 	struct mii_bus *mbus = smi->ext_mbus;
 
 	BUG_ON(in_interrupt());
@@ -293,7 +293,7 @@ int __rtl8366_mdio_read_reg(struct rtl8366_smi *smi, u32 addr, u32 *data)
 
 static int __rtl8366_mdio_write_reg(struct rtl8366_smi *smi, u32 addr, u32 data)
 {
-	u32 phy_id = MDC_REALTEK_PHY_ADDR;
+	u32 phy_id = smi->phy_id;
 	struct mii_bus *mbus = smi->ext_mbus;
 
 	BUG_ON(in_interrupt());
@@ -1547,6 +1547,9 @@ int rtl8366_smi_probe_of(struct platform_device *pdev, struct rtl8366_smi *smi)
 		goto try_gpio;
 	}
 
+	if (of_property_read_u32(np, "phy-id", &smi->phy_id))
+		smi->phy_id = MDC_REALTEK_PHY_ADDR;
+
 	return 0;
 
 try_gpio:
@@ -1586,6 +1589,7 @@ int rtl8366_smi_probe_plat(struct platform_device *pdev, struct rtl8366_smi *smi
 	smi->gpio_sda = pdata->gpio_sda;
 	smi->gpio_sck = pdata->gpio_sck;
 	smi->hw_reset = pdata->hw_reset;
+	smi->phy_id = MDC_REALTEK_PHY_ADDR;
 
 	return 0;
 }

target/linux/generic/files/drivers/net/phy/rtl8366_smi.h

@@ -63,6 +63,7 @@ struct rtl8366_smi {
 	u16			dbg_reg;
 	u8			dbg_vlan_4k_page;
 #endif
+	u32			phy_id;
 	struct mii_bus		*ext_mbus;
 };