From 79bcf7b02ba3d45bafe81a2753cedb8ef49548e3 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Fri, 22 Mar 2013 13:30:56 -0400 Subject: USB: EHCI: change return value of qh_completions() This patch (as1658) cleans up the usage of qh_completions() in ehci-hcd. Currently the function's return value indicates whether any URBs were given back; the idea was that the caller can scan the QH over again to handle any URBs that were dequeued by a completion handler. This is not necessary; when qh_completions() is ready to give back dequeued URBs, it does its own rescanning. Therefore the new return value will be a flag indicating whether the caller needs to unlink the QH. This is more convenient than forcing the caller to check qh->needs_rescan, and it makes a lot more sense -- why should "needs_rescan" imply that an unlink is needed? The callers are also changed to remove the unneeded rescans. Lastly, the check for whether qh->qtd_list is non-empty is removed from the start of qh_completions(). Two of the callers have to make this test anyway, so the same test can simply be added to the other two callers. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-sched.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) (limited to 'drivers/usb/host/ehci-sched.c') diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index 66259dc7822e..5c82bbab9a48 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -649,7 +649,8 @@ static void end_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh) qh->qh_state = QH_STATE_IDLE; hw->hw_next = EHCI_LIST_END(ehci); - qh_completions(ehci, qh); + if (!list_empty(&qh->qtd_list)) + qh_completions(ehci, qh); /* reschedule QH iff another request is queued */ if (!list_empty(&qh->qtd_list) && ehci->rh_state == EHCI_RH_RUNNING) { @@ -914,7 +915,7 @@ static void scan_intr(struct ehci_hcd *ehci) list_for_each_entry_safe(qh, ehci->qh_scan_next, &ehci->intr_qh_list, intr_node) { - rescan: + /* clean any finished work for this qh */ if (!list_empty(&qh->qtd_list)) { int temp; @@ -927,12 +928,9 @@ static void scan_intr(struct ehci_hcd *ehci) * in qh_unlink_periodic(). */ temp = qh_completions(ehci, qh); - if (unlikely(qh->needs_rescan || - (list_empty(&qh->qtd_list) && - qh->qh_state == QH_STATE_LINKED))) + if (unlikely(temp || (list_empty(&qh->qtd_list) && + qh->qh_state == QH_STATE_LINKED))) start_unlink_intr(ehci, qh); - else if (temp != 0) - goto rescan; } } } -- cgit