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path: root/drivers/usb/host
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Diffstat (limited to 'drivers/usb/host')
-rw-r--r--drivers/usb/host/ehci-sched.c41
1 files changed, 27 insertions, 14 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index 001b2c389be..8a8e08a51ba 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -2123,17 +2123,9 @@ scan_periodic (struct ehci_hcd *ehci)
for (;;) {
union ehci_shadow q, *q_p;
__hc32 type, *hw_p;
- unsigned uframes;
+ unsigned incomplete = false;
- /* don't scan past the live uframe */
frame = now_uframe >> 3;
- if (frame == (clock >> 3))
- uframes = now_uframe & 0x07;
- else {
- /* safe to scan the whole frame at once */
- now_uframe |= 0x07;
- uframes = 8;
- }
restart:
/* scan each element in frame's queue for completions */
@@ -2171,12 +2163,15 @@ restart:
q = q.fstn->fstn_next;
break;
case Q_TYPE_ITD:
- /* skip itds for later in the frame */
+ /* If this ITD is still active, leave it for
+ * later processing ... check the next entry.
+ */
rmb ();
- for (uf = live ? uframes : 8; uf < 8; uf++) {
+ for (uf = 0; uf < 8 && live; uf++) {
if (0 == (q.itd->hw_transaction [uf]
& ITD_ACTIVE(ehci)))
continue;
+ incomplete = true;
q_p = &q.itd->itd_next;
hw_p = &q.itd->hw_next;
type = Q_NEXT_TYPE(ehci,
@@ -2184,10 +2179,12 @@ restart:
q = *q_p;
break;
}
- if (uf != 8)
+ if (uf < 8 && live)
break;
- /* this one's ready ... HC won't cache the
+ /* Take finished ITDs out of the schedule
+ * and process them: recycle, maybe report
+ * URB completion. HC won't cache the
* pointer for much longer, if at all.
*/
*q_p = q.itd->itd_next;
@@ -2198,8 +2195,12 @@ restart:
q = *q_p;
break;
case Q_TYPE_SITD:
+ /* If this SITD is still active, leave it for
+ * later processing ... check the next entry.
+ */
if ((q.sitd->hw_results & SITD_ACTIVE(ehci))
&& live) {
+ incomplete = true;
q_p = &q.sitd->sitd_next;
hw_p = &q.sitd->hw_next;
type = Q_NEXT_TYPE(ehci,
@@ -2207,6 +2208,11 @@ restart:
q = *q_p;
break;
}
+
+ /* Take finished SITDs out of the schedule
+ * and process them: recycle, maybe report
+ * URB completion.
+ */
*q_p = q.sitd->sitd_next;
*hw_p = q.sitd->hw_next;
type = Q_NEXT_TYPE(ehci, q.sitd->hw_next);
@@ -2232,7 +2238,14 @@ restart:
}
}
- /* stop when we catch up to the HC */
+ /* If we can tell we caught up to the hardware, stop now.
+ * We can't advance our scan without collecting the ISO
+ * transfers that are still pending in this frame.
+ */
+ if (incomplete && HC_IS_RUNNING(ehci_to_hcd(ehci)->state)) {
+ ehci->next_uframe = now_uframe;
+ break;
+ }
// FIXME: this assumes we won't get lapped when
// latencies climb; that should be rare, but...