USB: allow match on bInterfaceNumber

Some composite USB devices provide multiple interfaces
with different functions, all using "vendor-specific"
for class/subclass/protocol.  Another OS use interface
numbers to match the driver and interface. It seems
these devices are designed with that in mind - using
static interface numbers for the different functions.

This adds support for matching against the
bInterfaceNumber, allowing such devices to be supported
without having to resort to testing against interface
number whitelists and/or blacklists in the probe.

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index f536aeb..23d7bbd 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -622,14 +622,15 @@
 	if (!usb_match_device(dev, id))
 		return 0;
 
-	/* The interface class, subclass, and protocol should never be
+	/* The interface class, subclass, protocol and number should never be
 	 * checked for a match if the device class is Vendor Specific,
 	 * unless the match record specifies the Vendor ID. */
 	if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
 			!(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 			(id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
 				USB_DEVICE_ID_MATCH_INT_SUBCLASS |
-				USB_DEVICE_ID_MATCH_INT_PROTOCOL)))
+				USB_DEVICE_ID_MATCH_INT_PROTOCOL |
+				USB_DEVICE_ID_MATCH_INT_NUMBER)))
 		return 0;
 
 	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
@@ -644,6 +645,10 @@
 	    (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
 		return 0;
 
+	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
+	    (id->bInterfaceNumber != intf->desc.bInterfaceNumber))
+		return 0;
+
 	return 1;
 }
 EXPORT_SYMBOL_GPL(usb_match_one_id);