* happens. The device's release function does a completion, so
* unregister_device does a remove event, device_unregister, a kref_put
* for the first reference, then waits on the completion for all other
* happens. The device's release function does a completion, so
* unregister_device does a remove event, device_unregister, a kref_put
* for the first reference, then waits on the completion for all other