usb_hcd_link_urb_to_ep — add an URB to its endpoint queue
|struct usb_hcd * hcd,|
|struct urb * urb|
Host controller drivers should call this routine in their
method. The HCD's private spinlock must be held and interrupts must
be disabled. The actions carried out here are required for URB
submission, as well as for endpoint shutdown and for usb_kill_urb.
0 for no error, otherwise a negative error code (in which case
enqueue method must fail). If no error occurs but
anyway, it must call
usb_hcd_unlink_urb_from_ep before releasing
the private spinlock and returning.