Also, follow the rules from watchdog(9) about what values to return in
various situations (especially, don't touch *error when asked to set a
non-zero timeout that isn't achievable on the hardware).
Also, move the READ/WRITE bus space access macros from the header into the
source file, and rename them to RD2/WR2 to make it clear they're 16-bit
accessors. (READ/WRITE just don't seem like good names to be in a public
header file.)
to check the status property in their probe routines.
Simplebus used to only instantiate its children whose status="okay"
but that was improper behavior, fixed in r261352. Now that it doesn't
check anymore and probes all its children; the children all have to
do the check because really only the children know how to properly
interpret their status property strings.
Right now all existing drivers only understand "okay" versus something-
that's-not-okay, so they all use the new ofw_bus_status_okay() helper.
