diff -urB ./usb/bus/usb/uhci.c ./usb_patched/bus/usb/uhci.c
--- ./usb/bus/usb/uhci.c	2010-06-20 10:20:58.000000000 +0200
+++ ./usb_patched/bus/usb/uhci.c	2010-06-20 10:59:03.000000000 +0200
@@ -612,8 +612,23 @@
   status = grub_uhci_readreg16 (u, reg);
   grub_dprintf ("uhci", "detect=0x%02x\n", status);
 
+  if (!enable) /* We don't need reset port */
+    {
+      /* Disable the port.  */
+      grub_uhci_writereg16 (u, reg, 0 << 2);
+      grub_dprintf ("uhci", "waiting for the port to be disabled\n");
+      endtime = grub_get_time_ms () + 1000;
+      while ((grub_uhci_readreg16 (u, reg) & (1 << 2)))
+        if (grub_get_time_ms () > endtime)
+          return grub_error (GRUB_ERR_IO, "UHCI Timed out");
+
+      status = grub_uhci_readreg16 (u, reg);
+      grub_dprintf ("uhci", ">3detect=0x%02x\n", status);
+      return GRUB_ERR_NONE;
+    }
+    
   /* Reset the port.  */
-  grub_uhci_writereg16 (u, reg, enable << 9);
+  grub_uhci_writereg16 (u, reg, 1 << 9);
 
   /* Wait for the reset to complete.  XXX: How long exactly?  */
   grub_millisleep (50); /* For root hub should be nominaly 50ms */
@@ -623,7 +638,7 @@
   grub_millisleep (10);
 
   /* Enable the port.  */
-  grub_uhci_writereg16 (u, reg, enable << 2);
+  grub_uhci_writereg16 (u, reg, 1 << 2);
   grub_millisleep (10);
 
   grub_dprintf ("uhci", "waiting for the port to be enabled\n");