diff --git a/drivers/usb/host/ohci-q.c b/drivers/usb/host/ohci-q.c index 517d04d5c150..a6376f3e55cb 100644 --- a/drivers/usb/host/ohci-q.c +++ b/drivers/usb/host/ohci-q.c @@ -311,8 +311,7 @@ static void periodic_unlink (struct ohci_hcd *ohci, struct ed *ed) * - ED_OPER: when there's any request queued, the ED gets rescheduled * immediately. HC should be working on them. * - * - ED_IDLE: when there's no TD queue. there's no reason for the HC - * to care about this ED; safe to disable the endpoint. + * - ED_IDLE: when there's no TD queue or the HC isn't running. * * When finish_unlinks() runs later, after SOF interrupt, it will often * complete one or more URB unlinks before making that state change. @@ -954,6 +953,10 @@ finish_unlinks (struct ohci_hcd *ohci, u16 tick) int completed, modified; __hc32 *prev; + /* Is this ED already invisible to the hardware? */ + if (ed->state == ED_IDLE) + goto ed_idle; + /* only take off EDs that the HC isn't using, accounting for * frame counter wraps and EDs with partially retired TDs */ @@ -983,12 +986,20 @@ finish_unlinks (struct ohci_hcd *ohci, u16 tick) } } + /* ED's now officially unlinked, hc doesn't see */ + ed->state = ED_IDLE; + if (quirk_zfmicro(ohci) && ed->type == PIPE_INTERRUPT) + ohci->eds_scheduled--; + ed->hwHeadP &= ~cpu_to_hc32(ohci, ED_H); + ed->hwNextED = 0; + wmb(); + ed->hwINFO &= ~cpu_to_hc32(ohci, ED_SKIP | ED_DEQUEUE); +ed_idle: + /* reentrancy: if we drop the schedule lock, someone might * have modified this list. normally it's just prepending * entries (which we'd ignore), but paranoia won't hurt. */ - *last = ed->ed_next; - ed->ed_next = NULL; modified = 0; /* unlink urbs as requested, but rescan the list after @@ -1046,19 +1057,20 @@ finish_unlinks (struct ohci_hcd *ohci, u16 tick) if (completed && !list_empty (&ed->td_list)) goto rescan_this; - /* ED's now officially unlinked, hc doesn't see */ - ed->state = ED_IDLE; - if (quirk_zfmicro(ohci) && ed->type == PIPE_INTERRUPT) - ohci->eds_scheduled--; - ed->hwHeadP &= ~cpu_to_hc32(ohci, ED_H); - ed->hwNextED = 0; - wmb (); - ed->hwINFO &= ~cpu_to_hc32 (ohci, ED_SKIP | ED_DEQUEUE); - - /* but if there's work queued, reschedule */ - if (!list_empty (&ed->td_list)) { - if (ohci->rh_state == OHCI_RH_RUNNING) - ed_schedule (ohci, ed); + /* + * If no TDs are queued, take ED off the ed_rm_list. + * Otherwise, if the HC is running, reschedule. + * If not, leave it on the list for further dequeues. + */ + if (list_empty(&ed->td_list)) { + *last = ed->ed_next; + ed->ed_next = NULL; + } else if (ohci->rh_state == OHCI_RH_RUNNING) { + *last = ed->ed_next; + ed->ed_next = NULL; + ed_schedule(ohci, ed); + } else { + last = &ed->ed_next; } if (modified)