diff -Naur a/hw/usb/core.c b/hw/usb/core.c
--- a/hw/usb/core.c	2014-12-08 16:39:08.682781480 +0300
+++ b/hw/usb/core.c	2014-12-08 16:40:46.516776567 +0300
@@ -28,26 +28,6 @@
 #include "qemu/iov.h"
 #include "trace.h"
 
-void usb_pick_speed(USBPort *port)
-{
-    static const int speeds[] = {
-        USB_SPEED_SUPER,
-        USB_SPEED_HIGH,
-        USB_SPEED_FULL,
-        USB_SPEED_LOW,
-    };
-    USBDevice *udev = port->dev;
-    int i;
-
-    for (i = 0; i < ARRAY_SIZE(speeds); i++) {
-        if ((udev->speedmask & (1 << speeds[i])) &&
-            (port->speedmask & (1 << speeds[i]))) {
-            udev->speed = speeds[i];
-            return;
-        }
-    }
-}
-
 void usb_attach(USBPort *port)
 {
     USBDevice *dev = port->dev;
@@ -55,7 +35,6 @@
     assert(dev != NULL);
     assert(dev->attached);
     assert(dev->state == USB_STATE_NOTATTACHED);
-    usb_pick_speed(port);
     port->ops->attach(port);
     dev->state = USB_STATE_ATTACHED;
     usb_device_handle_attach(dev);
diff -Naur a/hw/usb/desc.c b/hw/usb/desc.c
--- a/hw/usb/desc.c	2014-12-08 16:39:26.522780583 +0300
+++ b/hw/usb/desc.c	2014-12-08 16:42:31.385771299 +0300
@@ -518,6 +518,18 @@
 
 void usb_desc_attach(USBDevice *dev)
 {
+    const USBDesc *desc = usb_device_get_usb_desc(dev);
+
+    assert(desc != NULL);
+    if (desc->super && (dev->port->speedmask & USB_SPEED_MASK_SUPER)) {
+      dev->speed = USB_SPEED_SUPER;
+    } else if (desc->high && (dev->port->speedmask & USB_SPEED_MASK_HIGH)) {
+      dev->speed = USB_SPEED_HIGH;
+    } else if (desc->full && (dev->port->speedmask & USB_SPEED_MASK_FULL)) {
+      dev->speed = USB_SPEED_FULL;
+    } else {
+      return;
+    }
     usb_desc_setdefaults(dev);
 }
 
diff -Naur a/include/hw/usb.h b/include/hw/usb.h
--- a/include/hw/usb.h	2014-12-08 16:39:47.322779539 +0300
+++ b/include/hw/usb.h	2014-12-08 16:43:16.698769021 +0300
@@ -458,7 +458,6 @@
 void usb_combined_input_packet_complete(USBDevice *dev, USBPacket *p);
 void usb_combined_packet_cancel(USBDevice *dev, USBPacket *p);
 
-void usb_pick_speed(USBPort *port);
 void usb_attach(USBPort *port);
 void usb_detach(USBPort *port);
 void usb_port_reset(USBPort *port);