On Wed, 28 Aug 2013 12:02:03 +0800
Ming Lei <ming.lei@xxxxxxxxxxxxx> wrote:
> Actually the problem only happened when underrun without
> URB_ISO_ASAP.
>
> I have another fix which uses rebase trick and is simper(less change), could
> you comment on the attachment patch?
Sorry, please ignore last attachment patch, and comment on the below one:
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index 83be03f..4a3ddc9 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -1370,6 +1370,21 @@ sitd_slot_ok (
return 1;
}
+/* rebase in case of underun without ISO_ASAP together */
+static void iso_stream_rebase(struct ehci_hcd *ehci,
+ struct ehci_iso_stream *stream, u32 mod)
+{
+ u32 i;
+
+ if (ehci->last_base == -1)
+ return;
+
+ for (i = ehci->last_base; i != ehci->last_iso_frame;
+ i = (i + 1) & (mod - 1))
+ if ((stream->next_uframe & (mod - 1)) == i)
+ ehci->last_iso_frame = i;
+}
+
/*
* This scheduler plans almost as far into the future as it has actual
* periodic schedule slots. (Affected by TUNE_FLS, which defaults to
@@ -1409,7 +1424,9 @@ iso_stream_schedule (
* (irq delays etc). If there are, the behavior depends on
* whether URB_ISO_ASAP is set.
*/
- if (likely (!list_empty (&stream->td_list))) {
+ if (likely (!list_empty (&stream->td_list) ||
+ hcd_complete_in_progress(
+ ehci_to_hcd(ehci), urb))) {
/* Take the isochronous scheduling threshold into account */
if (ehci->i_thresh)
@@ -1417,6 +1434,10 @@ iso_stream_schedule (
else
next = (now + 2 + 7) & ~0x07; /* full frame cache */
+ if (list_empty(&stream->td_list) &&
+ !(urb->transfer_flags & URB_ISO_ASAP))
+ iso_stream_rebase(ehci, stream, mod);
+
/*
* Use ehci->last_iso_frame as the base. There can't be any
* TDs scheduled for earlier than that.
@@ -1517,6 +1538,7 @@ iso_stream_schedule (
/* Make sure scan_isoc() sees these */
if (ehci->isoc_count == 0)
ehci->last_iso_frame = now >> 3;
+ ehci->last_base = -1;
return 0;
fail:
@@ -2255,6 +2277,9 @@ static void scan_isoc(struct ehci_hcd *ehci)
}
ehci->now_frame = now_frame;
+ if (ehci->last_base == -1)
+ ehci->last_base = ehci->last_iso_frame;
+
frame = ehci->last_iso_frame;
for (;;) {
union ehci_shadow q, *q_p;
Thanks,
--
Ming Lei
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
