[09/12] ehci: Set int flag on a short input packet

Submitted by Hans de Goede on Oct. 8, 2012, 7:51 a.m.

Details

Message ID 1349682696-3046-10-git-send-email-hdegoede@redhat.com
State New
Headers show

Commit Message

Hans de Goede Oct. 8, 2012, 7:51 a.m.
According to 4.15.1.2 an interrupt must be raised when a short packet
is received. If we don't do this it may take a significant time for
the guest to notice a short trasnfer has completed, since only the last td
will have its IOC flag set, and a short transfer may complete in an earlier
packet.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 hw/usb/hcd-ehci.c | 4 ++++
 1 file changed, 4 insertions(+)

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diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index 6945992..d9d4918 100644
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -1508,6 +1508,10 @@  static void ehci_execute_complete(EHCIQueue *q)
 
         if (tbytes && p->pid == USB_TOKEN_IN) {
             tbytes -= p->usb_status;
+            if (tbytes) {
+                /* 4.15.1.2 must raise int on a short input packet */
+                ehci_raise_irq(q->ehci, USBSTS_INT);
+            }
         } else {
             tbytes = 0;
         }