usb_block_urb (9) - Linux Man Pages
usb_block_urb: reliably prevent further use of an URB
usb_block_urb - reliably prevent further use of an URB
void usb_block_urb(struct urb
- pointer to URB to be blocked, may be NULL
After the routine has run, attempts to resubmit the URB will fail with error -EPERM. Thus even if the URB's completion handler always tries to resubmit, it will not succeed and the URB will become idle.