devnum
device number
parport
pointer to storage for parallel port number
mux
pointer to storage for multiplexor port number
daisy
pointer to storage for daisy chain address
This function converts a device number into its coordinates in terms of which parallel port in the system it is attached to, which multiplexor port it is attached to if there is a multiplexor on that port, and which daisy chain address it has if it is in a daisy chain.
The caller must allocate storage for parport
, mux
, and
daisy
.
If there is no device with the specified device number, -ENXIO
is returned. Otherwise, the values pointed to by parport
,
mux
, and daisy
are set to the coordinates of the device,
with -1 for coordinates with no value.
This function is not actually very useful, but this interface was suggested by IEEE 1284.3.