diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c index 3d989028c8365e6644b86428fea2f24cfba9be6e..fd252f0cfb3a7873ec7bad8226a036a9668b182e 100644 --- a/drivers/usb/host/ehci-q.c +++ b/drivers/usb/host/ehci-q.c @@ -1197,17 +1197,26 @@ static void start_iaa_cycle(struct ehci_hcd *ehci, bool nested) if (ehci->async_iaa || ehci->async_unlinking) return; - /* Do all the waiting QHs at once */ - ehci->async_iaa = ehci->async_unlink; - ehci->async_unlink = NULL; - /* If the controller isn't running, we don't have to wait for it */ if (unlikely(ehci->rh_state < EHCI_RH_RUNNING)) { + + /* Do all the waiting QHs */ + ehci->async_iaa = ehci->async_unlink; + ehci->async_unlink = NULL; + if (!nested) /* Avoid recursion */ end_unlink_async(ehci); /* Otherwise start a new IAA cycle */ } else if (likely(ehci->rh_state == EHCI_RH_RUNNING)) { + struct ehci_qh *qh; + + /* Do only the first waiting QH (nVidia bug?) */ + qh = ehci->async_unlink; + ehci->async_iaa = qh; + ehci->async_unlink = qh->unlink_next; + qh->unlink_next = NULL; + /* Make sure the unlinks are all visible to the hardware */ wmb(); @@ -1255,34 +1264,35 @@ static void end_unlink_async(struct ehci_hcd *ehci) } } +static void start_unlink_async(struct ehci_hcd *ehci, struct ehci_qh *qh); + static void unlink_empty_async(struct ehci_hcd *ehci) { - struct ehci_qh *qh, *next; - bool stopped = (ehci->rh_state < EHCI_RH_RUNNING); + struct ehci_qh *qh; + struct ehci_qh *qh_to_unlink = NULL; bool check_unlinks_later = false; + int count = 0; - /* Unlink all the async QHs that have been empty for a timer cycle */ - next = ehci->async->qh_next.qh; - while (next) { - qh = next; - next = qh->qh_next.qh; - + /* Find the last async QH which has been empty for a timer cycle */ + for (qh = ehci->async->qh_next.qh; qh; qh = qh->qh_next.qh) { if (list_empty(&qh->qtd_list) && qh->qh_state == QH_STATE_LINKED) { - if (!stopped && qh->unlink_cycle == - ehci->async_unlink_cycle) + ++count; + if (qh->unlink_cycle == ehci->async_unlink_cycle) check_unlinks_later = true; else - single_unlink_async(ehci, qh); + qh_to_unlink = qh; } } - /* Start a new IAA cycle if any QHs are waiting for it */ - if (ehci->async_unlink) - start_iaa_cycle(ehci, false); + /* If nothing else is being unlinked, unlink the last empty QH */ + if (!ehci->async_iaa && !ehci->async_unlink && qh_to_unlink) { + start_unlink_async(ehci, qh_to_unlink); + --count; + } - /* QHs that haven't been empty for long enough will be handled later */ - if (check_unlinks_later) { + /* Other QHs will be handled later */ + if (count > 0) { ehci_enable_event(ehci, EHCI_HRTIMER_ASYNC_UNLINKS, true); ++ehci->async_unlink_cycle; }