net: usb: r8152: Add in new Devices that are supported for Mac-Passthru

Lenovo Thunderbolt 4 Dock, and other Lenovo USB Docks are using the
original Realtek USB ethernet Vendor and Product IDs
If the Network device is Realtek verify that it is on a Lenovo USB hub
before enabling the passthru feature

This also adds in the device IDs for the Lenovo USB Dongle and one other
USB-C dock

V2 fix formating of code
V3 remove Generic define for Device ID 0x8153 and change it to use value
V4 rearrange defines and case statement to put them in better order
v5 create helper function to do the testing work as suggested

Signed-off-by: David Ober <dober6023@gmail.com>
Link: https://lore.kernel.org/r/20220517180539.25839-1-dober6023@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/usb/r8152.c

@@ -771,7 +771,9 @@ enum rtl8152_flags {
 };
 
 #define DEVICE_ID_THINKPAD_THUNDERBOLT3_DOCK_GEN2	0x3082
+#define DEVICE_ID_THINKPAD_USB_C_DONGLE			0x720c
 #define DEVICE_ID_THINKPAD_USB_C_DOCK_GEN2		0xa387
+#define DEVICE_ID_THINKPAD_USB_C_DOCK_GEN3		0x3062
 
 struct tally_counter {
 	__le64	tx_packets;
@@ -9562,6 +9564,29 @@ u8 rtl8152_get_version(struct usb_interface *intf)
 }
 EXPORT_SYMBOL_GPL(rtl8152_get_version);
 
+static bool rtl8152_supports_lenovo_macpassthru(struct usb_device *udev)
+{
+	int parent_vendor_id = le16_to_cpu(udev->parent->descriptor.idVendor);
+	int product_id = le16_to_cpu(udev->descriptor.idProduct);
+	int vendor_id = le16_to_cpu(udev->descriptor.idVendor);
+
+	if (vendor_id == VENDOR_ID_LENOVO) {
+		switch (product_id) {
+		case DEVICE_ID_THINKPAD_THUNDERBOLT3_DOCK_GEN2:
+		case DEVICE_ID_THINKPAD_USB_C_DOCK_GEN2:
+		case DEVICE_ID_THINKPAD_USB_C_DOCK_GEN3:
+		case DEVICE_ID_THINKPAD_USB_C_DONGLE:
+			return 1;
+		}
+	} else if (vendor_id == VENDOR_ID_REALTEK && parent_vendor_id == VENDOR_ID_LENOVO) {
+		switch (product_id) {
+		case 0x8153:
+			return 1;
+		}
+	}
+	return 0;
+}
+
 static int rtl8152_probe(struct usb_interface *intf,
 			 const struct usb_device_id *id)
 {
@@ -9642,13 +9667,7 @@ static int rtl8152_probe(struct usb_interface *intf,
 		netdev->hw_features &= ~NETIF_F_RXCSUM;
 	}
 
-	if (le16_to_cpu(udev->descriptor.idVendor) == VENDOR_ID_LENOVO) {
-		switch (le16_to_cpu(udev->descriptor.idProduct)) {
-		case DEVICE_ID_THINKPAD_THUNDERBOLT3_DOCK_GEN2:
-		case DEVICE_ID_THINKPAD_USB_C_DOCK_GEN2:
-			tp->lenovo_macpassthru = 1;
-		}
-	}
+	tp->lenovo_macpassthru = rtl8152_supports_lenovo_macpassthru(udev);
 
 	if (le16_to_cpu(udev->descriptor.bcdDevice) == 0x3011 && udev->serial &&
 	    (!strcmp(udev->serial, "000001000000") ||