USB: create module_usb_serial_driver macro

Now that Alan Stern has cleaned up the usb serial driver registration,
we have the ability to create a module_usb_serial_driver macro to make
things a bit simpler, like the other *_driver macros created.

But, as we need two functions here, we can't reuse the existing
module_driver() macro, so we need to roll our own.

Here's a patch implementing module_usb_serial_driver() and it converts
the pl2303 driver to use it, showing a nice cleanup.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h
index 34c06a723dcc..7b1db841e2a8 100644
--- a/include/linux/usb/serial.h
+++ b/include/linux/usb/serial.h
@@ -406,5 +406,33 @@ do {									\
         }                                                               \
 } while (0)
 
+/*
+ * module_usb_serial_driver() - Helper macro for registering a USB Serial driver
+ * @__usb_driver: usb_driver struct to register
+ * @__serial_drivers: list of usb_serial drivers to register
+ *
+ * Helper macro for USB serial drivers which do not do anything special
+ * in module init/exit. This eliminates a lot of boilerplate. Each
+ * module may only use this macro once, and calling it replaces
+ * module_init() and module_exit()
+ *
+ * Note, we can't use the generic module_driver() call here, due to the
+ * two parameters in the usb_serial_* functions, so we roll our own here
+ * :(
+ */
+#define module_usb_serial_driver(__usb_driver, __serial_drivers)        \
+static int __init usb_serial_driver_init(void)                          \
+{                                                                       \
+        return usb_serial_register_drivers(&(__usb_driver),             \
+                                           (__serial_drivers));         \
+}                                                                       \
+module_init(usb_serial_driver_init);                                    \
+static void __exit usb_serial_driver_exit(void)                         \
+{                                                                       \
+        return usb_serial_deregister_drivers(&(__usb_driver),           \
+                                             (__serial_drivers));       \
+}                                                                       \
+module_exit(usb_serial_driver_exit);
+
 #endif /* __LINUX_USB_SERIAL_H */