USB_HCD_CHECK_UNLINK(9) Host Controller APIs USB_HCD_CHECK_UNLINK(9)NAMEusb_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 urb was submitted
urb
URB being checked for unlinkability
status
error code to store in urb if 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.
Returns 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.
COPYRIGHTKernel Hackers Manual 2.6. November 2013 USB_HCD_CHECK_UNLINK(9)