if (pNvAcpiObject->notify_handler_installed)
{
#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 13, 0)
/* beginning with 3.13, acpi_remove_notify_handler() waits for events to finish */
NV_ACPI_OS_WAIT_EVENTS_COMPLETE();
#endif
// remove event notifier
status = acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, nv_acpi_event);