USB: add support for dev_groups to struct usb_driver

Now that the driver core supports dev_groups for individual drivers,
expose that pointer to struct usb_driver to make it easier for USB
drivers to also use it.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190806144502.17792-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/driver.c

@@ -954,6 +954,7 @@ int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
 	new_driver->drvwrap.driver.remove = usb_unbind_interface;
 	new_driver->drvwrap.driver.owner = owner;
 	new_driver->drvwrap.driver.mod_name = mod_name;
+	new_driver->drvwrap.driver.dev_groups = new_driver->dev_groups;
 	spin_lock_init(&new_driver->dynids.lock);
 	INIT_LIST_HEAD(&new_driver->dynids.list);
 

include/linux/usb.h

@@ -1151,6 +1151,8 @@ struct usbdrv_wrap {
  * @id_table: USB drivers use ID table to support hotplugging.
  *	Export this with MODULE_DEVICE_TABLE(usb,...).  This must be set
  *	or your driver's probe function will never get called.
+ * @dev_groups: Attributes attached to the device that will be created once it
+ *	is bound to the driver.
  * @dynids: used internally to hold the list of dynamically added device
  *	ids for this driver.
  * @drvwrap: Driver-model core structure wrapper.
@@ -1198,6 +1200,7 @@ struct usb_driver {
 	int (*post_reset)(struct usb_interface *intf);
 
 	const struct usb_device_id *id_table;
+	const struct attribute_group **dev_groups;
 
 	struct usb_dynids dynids;
 	struct usbdrv_wrap drvwrap;