OHCI: implement new semantics for URB_ISO_ASAP
This patch (as1614) updates the isochronous scheduling in ohci-hcd to
match the new semantics for URB_ISO_ASAP. Testing revealed a hardware
bug in the way my OHCI controller handles expired isochronous TDs;
consequently the patch tries hard to avoid creating them (unlike the
ehci-hcd and uhci-hcd drivers).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/host/ohci-q.c b/drivers/usb/host/ohci-q.c
index c5a1ea9..177a213 100644
--- a/drivers/usb/host/ohci-q.c
+++ b/drivers/usb/host/ohci-q.c
@@ -596,7 +596,6 @@
urb_priv->ed->hwHeadP &= ~cpu_to_hc32 (ohci, ED_C);
}
- urb_priv->td_cnt = 0;
list_add (&urb_priv->pending, &ohci->pending);
if (data_len)
@@ -672,7 +671,8 @@
* we could often reduce the number of TDs here.
*/
case PIPE_ISOCHRONOUS:
- for (cnt = 0; cnt < urb->number_of_packets; cnt++) {
+ for (cnt = urb_priv->td_cnt; cnt < urb->number_of_packets;
+ cnt++) {
int frame = urb->start_frame;
// FIXME scheduling should handle frame counter