[Qemu-devel] [PATCH 09/12] ehci: Set int flag on a short input packet

[Hans de Goede]

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 <address@hidden>
---
 hw/usb/hcd-ehci.c | 4 ++++
 1 file changed, 4 insertions(+)

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;
         }
-- 
1.7.12.1