Entry points: Autoconfiguration


struct cfattach hpa_ca = {
      sizeof (struct hpa_softc), hpa_match, hpa_attach
};

Our device state is stored in the software configuration (softc)
structure, which gets set to zero for us.

Probe/Match:

Do a test to tell if our device is there, usually with the help of some bus specific functions.
Return 1 if we have a match, or 0 otherwise.

Attach:

Initialise device
map memory
map Interrupt or start polling timer
setup higher level abstraction structures (ie ifnet for network drivers)
start other timers