the driver_data may be used for sanity check, it fails the
probe() if driver_data is NULL after it is re-triggered.
for example, soc_probe() in sound/soc/soc-core.c
Signed-off-by: Yi Zhang <yizhang_hust@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>