Add a driver that decodes the Reset Status Register (RSR) of the
Freescale ColdFire MCF5441x Reset Controller Module at probe time
and exposes the cause via the power_on_reason sysfs ABI.
The RSR can latch several cause bits simultaneously (Reference
Manual chapter 12.3.2); the driver picks one cause per a priority
that favours the most explanatory diagnostic.
The register layout is described in the driver so it can be built
with COMPILE_TEST on any architecture.
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
Link: https://patch.msgid.link/20260617-coldfire-rcm-power-on-reason-v3-1-1a7c7b6b14e7@yoseli.org
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
