The method ieee802154_radio_handle_ack() does not belong to the
PHY/radio layer but to the L2 layer. It is a callback called from the
radio layer into the L2 layer and to be implemented by all L2 stacks.
This is the same pattern as is used for ieee802154_init(). The
'_radio_' infix in this function is therefore confusing and
conceptually wrong.
This change fixes the naming inconsistency and extensively documents
its rationale.
It is assumed that the change can be made without prior deprecation of the
existing method as in the rare cases where users have implemented custom
radio drivers these will break in obvious ways and can easily be fixed.
Nevertheless such a rename would not be justified on its own if it were
not for an important conceptual reason:
The renamed function represents a generic "inversion-of-control" pattern
which will become important in the TSCH context: It allows for clean
separation of concerns between the PHY/radio driver layer and the
MAC/L2 layer even in situations where the radio driver needs to be
involved for performance or deterministic timing reasons. This
"inversion-of-control" pattern can be applied to negotiate timing
sensitive reception and transmission windows, it let's the L2 layer
deterministically timestamp information elements just-in-time with
internal radio timer counter values, etc.
Signed-off-by: Florian Grandel <fgrandel@code-for-humans.de>