Name
usb_hcd_check_unlink_urb — 
     check whether an URB may be unlinked
 
Synopsis
| int usb_hcd_check_unlink_urb ( | struct usb_hcd * hcd, | 
|  | struct urb * urb, | 
|  | int status ); | 
 
Arguments
- hcd
- 
     host controller to which - urbwas submitted
 
- urb
- 
     URB being checked for unlinkability
     
- status
- 
     error code to store in - urbif the unlink succeeds
 
Description
   Host controller drivers should call this routine in their dequeue
   method.  The HCD's private spinlock must be held and interrupts must
   be disabled.  The actions carried out here are required for making
   sure than an unlink is valid.
Return
   0 for no error, otherwise a negative error code (in which case
   the dequeue method must fail).  The possible error codes are:
   
   -EIDRM: urb was not submitted or has already completed.
   The completion function may not have been called yet.
   
   -EBUSY: urb has already been unlinked.