USB: Select better matching USB drivers when available

Now that USB device drivers can reuse code from the generic USB device
driver, we need to make sure that they get selected rather than the
generic driver. Add an id_table and match vfunc to the usb_device_driver
struct, which will get used to select a better matching driver at
->probe time.

This is a similar mechanism to that used in the HID drivers, with the
generic driver being selected unless there's a better matching one found
in the registered drivers (see hid_generic_match() in
drivers/hid/hid-generic.c).

Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-5-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/usb.h b/include/linux/usb.h
index 94bd3b48a485..3663bd7b1fa4 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -1237,6 +1237,7 @@ struct usb_driver {
 struct usb_device_driver {
 	const char *name;
 
+	bool (*match) (struct usb_device *udev);
 	int (*probe) (struct usb_device *udev);
 	void (*disconnect) (struct usb_device *udev);
 
@@ -1244,6 +1245,7 @@ struct usb_device_driver {
 	int (*resume) (struct usb_device *udev, pm_message_t message);
 	const struct attribute_group **dev_groups;
 	struct usbdrv_wrap drvwrap;
+	const struct usb_device_id *id_table;
 	unsigned int supports_autosuspend:1;
 	unsigned int generic_subclass:1;
 };