regulator: irq_helpers: duplicate IRQ name

The regulator IRQ helper requires caller to provide pointer to IRQ name
which is kept in memory by caller. All other data passed to the helper
in the regulator_irq_desc structure is copied. This can cause some
confusion and unnecessary complexity.

Make the regulator_irq_helper() to copy also the provided IRQ name
information so caller can discard the name after the call to
regulator_irq_helper() completes.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://msgid.link/r/ZhJMuUYwaZbBXFGP@drtxq0yyyyyyyyyyyyydy-3.rev.dnainternet.fi
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: irq_helper: Provide helper for trivial IRQ notifications

Provide a generic map_event helper for regulators which have a notification
IRQ with single, well defined purpose. Eg, IRQ always indicates exactly one
event for exactly one regulator device. For such IRQs the mapping is
trivial.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/603b7ed1938013a00371c1e7ccc63dfb16982b87.1637736436.git.matti.vaittinen@fi.rohmeurope.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: Documentation fix for regulator error notification helper

The helper to send IRQ notification for regulator errors had still
old description mentioning calling BUG() as a last resort when
error status reading has kept failing for more times than a given
threshold.

The impementation calling BUG() did never end-up in-tree but was
replaced by hopefully more sophisticated handler trying to power-off
the system.

Fix the documentation to reflect actual behaviour.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/20210823075651.GA3717293@localhost.localdomain
Signed-off-by: Mark Brown <broonie@kernel.org>

regulator: IRQ based event/error notification helpers

Provide helper function for IC's implementing regulator notifications
when an IRQ fires. The helper also works for IRQs which can not be acked.
Helper can be set to disable the IRQ at handler and then re-enabling it
on delayed work later. The helper also adds regulator_get_error_flags()
errors in cache for the duration of IRQ disabling.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/ebdf86d8c22b924667ec2385330e30fcbfac0119.1622628334.git.matti.vaittinen@fi.rohmeurope.com
Signed-off-by: Mark Brown <broonie@kernel.org>