Provided by:
linux-doc-2.6.15_2.6.15-23.39_all 
NAME
usb_hcd_giveback_urb - return URB from HCD to device driver
SYNOPSIS
void usb_hcd_giveback_urb (struct usb_hcd * hcd, struct urb * urb,
struct pt_regs * regs);
ARGUMENTS
hcd host controller returning the URB
urb urb being returned to the USB device driver.
regs pt_regs, passed down to the URB completion handler
CONTEXT
in_interrupt
DESCRIPTION
This hands the URB from HCD to its USB device driver, using its
completion function. The HCD has freed all per-urb resources (and is
done using urb->hcpriv). It also released all HCD locks; the device
driver won’t cause problems if it frees, modifies, or resubmits this
URB.