HPET_PERIODIC
if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) {
if (devp->hd_flags & HPET_PERIODIC
devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
if (devp->hd_flags & HPET_PERIODIC) {
devp->hd_flags |= HPET_PERIODIC;
if (devp->hd_flags & HPET_PERIODIC &&
devp->hd_flags &= ~HPET_PERIODIC;