anchor.diff:                        value
                         index
                         length)
  -      (setf (gethash msg-td (td->td-info ohci)) td-info
  +      (setf (td-info-event-type msg-td-info) event-type
  +            (td-info-endpoint msg-td-info) endpoint
  +            (td-info-buf-size msg-td-info) 8
  +            (td-info-buf msg-td-info) msg-buf
               (ed-tdq-tail ed) (array->phys-addr dummy-td))
   
         (with-trace-level (3)
  
positive.code:   (with-trace-level (1)
      (sup:debug-print-line "delete device"))
    (with-hcd-access (ohci)
      (let* ((bar0 (bar ohci))
             (ed (device-control-ed device))
             (ed-phys-addr (array->phys-addr ed)))
  
        ;; remove control-ed from list
  
negative.code:                                 status
                                  (td-xfer-bytes td (td-info-buf-size td-info))
                                  (td-info-buf td-info))))
        (free-td ohci td))))
  
  ;;======================================================================
  ;; set-device-address
  