css_driver_unregister
css_driver_unregister(&chsc_subchannel_driver);
EXPORT_SYMBOL_GPL(css_driver_unregister);
extern void css_driver_unregister(struct css_driver *);
css_driver_unregister(&eadm_subchannel_driver);
css_driver_unregister(&vfio_ccw_sch_driver);