IRQS_WAITING
if (i < 16 && !(desc->istate & IRQS_WAITING))
if (!(desc->istate & IRQS_WAITING)) {
desc->istate |= IRQS_AUTODETECT | IRQS_WAITING;
if (!(desc->istate & IRQS_WAITING)) {
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
___PS(IRQS_WAITING);
BIT_MASK_DESCR(IRQS_WAITING),
IRQS_ONESHOT | IRQS_WAITING);