diff options
Diffstat (limited to 'drivers/usb/host/ehci-sched.c')
-rw-r--r-- | drivers/usb/host/ehci-sched.c | 47 |
1 files changed, 45 insertions, 2 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index 8e3c878f38cf..66310894ad97 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -601,12 +601,29 @@ static void qh_unlink_periodic(struct ehci_hcd *ehci, struct ehci_qh *qh) list_del(&qh->intr_node); } +static void cancel_unlink_wait_intr(struct ehci_hcd *ehci, struct ehci_qh *qh) +{ + if (qh->qh_state != QH_STATE_LINKED || + list_empty(&qh->unlink_node)) + return; + + list_del_init(&qh->unlink_node); + + /* + * TODO: disable the event of EHCI_HRTIMER_START_UNLINK_INTR for + * avoiding unnecessary CPU wakeup + */ +} + static void start_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh) { /* If the QH isn't linked then there's nothing we can do. */ if (qh->qh_state != QH_STATE_LINKED) return; + /* if the qh is waiting for unlink, cancel it now */ + cancel_unlink_wait_intr(ehci, qh); + qh_unlink_periodic (ehci, qh); /* Make sure the unlinks are visible before starting the timer */ @@ -632,6 +649,27 @@ static void start_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh) } } +/* + * It is common only one intr URB is scheduled on one qh, and + * given complete() is run in tasklet context, introduce a bit + * delay to avoid unlink qh too early. + */ +static void start_unlink_intr_wait(struct ehci_hcd *ehci, + struct ehci_qh *qh) +{ + qh->unlink_cycle = ehci->intr_unlink_wait_cycle; + + /* New entries go at the end of the intr_unlink_wait list */ + list_add_tail(&qh->unlink_node, &ehci->intr_unlink_wait); + + if (ehci->rh_state < EHCI_RH_RUNNING) + ehci_handle_start_intr_unlinks(ehci); + else if (ehci->intr_unlink_wait.next == &qh->unlink_node) { + ehci_enable_event(ehci, EHCI_HRTIMER_START_UNLINK_INTR, true); + ++ehci->intr_unlink_wait_cycle; + } +} + static void end_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh) { struct ehci_qh_hw *hw = qh->hw; @@ -889,6 +927,9 @@ static int intr_submit ( if (qh->qh_state == QH_STATE_IDLE) { qh_refresh(ehci, qh); qh_link_periodic(ehci, qh); + } else { + /* cancel unlink wait for the qh */ + cancel_unlink_wait_intr(ehci, qh); } /* ... update usbfs periodic stats */ @@ -924,9 +965,11 @@ static void scan_intr(struct ehci_hcd *ehci) * in qh_unlink_periodic(). */ temp = qh_completions(ehci, qh); - if (unlikely(temp || (list_empty(&qh->qtd_list) && - qh->qh_state == QH_STATE_LINKED))) + if (unlikely(temp)) start_unlink_intr(ehci, qh); + else if (unlikely(list_empty(&qh->qtd_list) && + qh->qh_state == QH_STATE_LINKED)) + start_unlink_intr_wait(ehci, qh); } } } |