diff --git a/hw/usb-hub.c b/hw/usb-hub.c
index 477927b..6e2a358 100644
--- a/hw/usb-hub.c
+++ b/hw/usb-hub.c
@@ -495,7 +495,7 @@
         port = &s->ports[i];
         dev = port->port.dev;
         if (dev && (port->wPortStatus & PORT_STAT_ENABLE)) {
-            ret = dev->info->handle_packet(dev, p);
+            ret = usb_handle_packet(dev, p);
             if (ret != USB_RET_NODEV) {
                 return ret;
             }
diff --git a/hw/usb-musb.c b/hw/usb-musb.c
index 38986d3..6037193 100644
--- a/hw/usb-musb.c
+++ b/hw/usb-musb.c
@@ -601,7 +601,7 @@
     ep->packey[dir].dir = dir;
 
     if (s->port.dev)
-        ret = s->port.dev->info->handle_packet(s->port.dev, &ep->packey[dir].p);
+        ret = usb_handle_packet(s->port.dev, &ep->packey[dir].p);
     else
         ret = USB_RET_NODEV;
 
diff --git a/hw/usb-ohci.c b/hw/usb-ohci.c
index 32913eb..8b966f7 100644
--- a/hw/usb-ohci.c
+++ b/hw/usb-ohci.c
@@ -748,7 +748,7 @@
             ohci->usb_packet.devep = OHCI_BM(ed->flags, ED_EN);
             ohci->usb_packet.data = ohci->usb_buf;
             ohci->usb_packet.len = len;
-            ret = dev->info->handle_packet(dev, &ohci->usb_packet);
+            ret = usb_handle_packet(dev, &ohci->usb_packet);
             if (ret != USB_RET_NODEV)
                 break;
         }
@@ -944,7 +944,7 @@
             ohci->usb_packet.devep = OHCI_BM(ed->flags, ED_EN);
             ohci->usb_packet.data = ohci->usb_buf;
             ohci->usb_packet.len = len;
-            ret = dev->info->handle_packet(dev, &ohci->usb_packet);
+            ret = usb_handle_packet(dev, &ohci->usb_packet);
             if (ret != USB_RET_NODEV)
                 break;
         }
diff --git a/hw/usb-uhci.c b/hw/usb-uhci.c
index 1e9c1e7..c0de05b 100644
--- a/hw/usb-uhci.c
+++ b/hw/usb-uhci.c
@@ -632,7 +632,7 @@
         USBDevice *dev = port->port.dev;
 
         if (dev && (port->ctrl & UHCI_PORT_EN))
-            ret = dev->info->handle_packet(dev, p);
+            ret = usb_handle_packet(dev, p);
     }
 
     DPRINTF("uhci: packet exit. ret %d len %d\n", ret, p->len);
diff --git a/hw/usb.c b/hw/usb.c
index 60027c6..966cb0f 100644
--- a/hw/usb.c
+++ b/hw/usb.c
@@ -297,9 +297,22 @@
 void usb_send_msg(USBDevice *dev, int msg)
 {
     USBPacket p;
+    int ret;
+
     memset(&p, 0, sizeof(p));
     p.pid = msg;
-    dev->info->handle_packet(dev, &p);
-
+    ret = usb_handle_packet(dev, &p);
     /* This _must_ be synchronous */
+    assert(ret != USB_RET_ASYNC);
+}
+
+/* Hand over a packet to a device for processing.  Return value
+   USB_RET_ASYNC indicates the processing isn't finished yet, the
+   driver will call usb_packet_complete() when done processing it. */
+int usb_handle_packet(USBDevice *dev, USBPacket *p)
+{
+    int ret;
+
+    ret = dev->info->handle_packet(dev, p);
+    return ret;
 }
diff --git a/hw/usb.h b/hw/usb.h
index c1d1014..6889467 100644
--- a/hw/usb.h
+++ b/hw/usb.h
@@ -266,6 +266,8 @@
     void *cancel_opaque;
 };
 
+int usb_handle_packet(USBDevice *dev, USBPacket *p);
+
 /* Defer completion of a USB packet.  The hadle_packet routine should then
    return USB_RET_ASYNC.  Packets that complete immediately (before
    handle_packet returns) should not call this method.  */