usb_block_urb
usb_block_urb(usbhid->urbout);
usb_block_urb(usbhid->urbctrl);
usb_block_urb(io->urbs[i]);
usb_block_urb(io->urbs[i]);
EXPORT_SYMBOL_GPL(usb_block_urb);
extern void usb_block_urb(struct urb *urb);