[PATCH net-next v2] r8152: avoid to change cfg for all devices

[Hayes Wang <hayeswang@realtek.com>]

The rtl8152_cfgselector_probe() should set the USB configuration to the
vendor mode only for the devices which the driver (r8152) supports.
Otherwise, no driver would be used for such devices.

Fixes: ec51fbd1b8a2 ("r8152: add USB device driver for config selection")
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
---
v2: fix a typo for the comment.

 drivers/net/usb/r8152.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index a26d3127a4fe..4c5c1df5d7a4 100644
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -9500,9 +9500,8 @@ static int rtl_fw_init(struct r8152 *tp)
 	return 0;
 }
 
-u8 rtl8152_get_version(struct usb_interface *intf)
+static u8 __rtl_get_hw_ver(struct usb_device *udev)
 {
-	struct usb_device *udev = interface_to_usbdev(intf);
 	u32 ocp_data = 0;
 	__le32 *tmp;
 	u8 version;
@@ -9571,10 +9570,19 @@ u8 rtl8152_get_version(struct usb_interface *intf)
 		break;
 	default:
 		version = RTL_VER_UNKNOWN;
-		dev_info(&intf->dev, "Unknown version 0x%04x\n", ocp_data);
+		dev_info(&udev->dev, "Unknown version 0x%04x\n", ocp_data);
 		break;
 	}
 
+	return version;
+}
+
+u8 rtl8152_get_version(struct usb_interface *intf)
+{
+	u8 version;
+
+	version = __rtl_get_hw_ver(interface_to_usbdev(intf));
+
 	dev_dbg(&intf->dev, "Detected version 0x%04x\n", version);
 
 	return version;
@@ -9870,6 +9878,12 @@ static int rtl8152_cfgselector_probe(struct usb_device *udev)
 	struct usb_host_config *c;
 	int i, num_configs;
 
+	/* Switch the device to vendor mode, if and only if the vendor mode
+	 * driver supports it.
+	 */
+	if (__rtl_get_hw_ver(udev) == RTL_VER_UNKNOWN)
+		return 0;
+
 	/* The vendor mode is not always config #1, so to find it out. */
 	c = udev->config;
 	num_configs = udev->descriptor.bNumConfigurations;
-- 
2.38.1