Provided by: linux-doc-2.6.15_2.6.15-23.39_all bug


       struct usb_sg_request - support for scatter/gather I/O


       struct usb_sg_request {
         int status;
         size_t bytes;


       status zero indicates success, else negative errno

       bytes  counts bytes transferred.


       These  requests are initialized using usb_sg_init, and then are used as
       request handles passed to usb_sg_wait or usb_sg_cancel. Most members of
       the request object aren’t for driver access.

       The  status  and  bytecount  values  are  valid  only after usb_sg_wait
       returns. If the status is zero, then the bytecount  matches  the  total
       from the request.

       After  an  error completion, drivers may need to clear a halt condition
       on the endpoint.