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>

drivers/regulator/irq_helpers.c

@@ -184,7 +184,7 @@ static irqreturn_t regulator_notifier_isr(int irq, void *data)
 	 * If retry_count exceeds the given safety limit we call IC specific die
 	 * handler which can try disabling regulator(s).
 	 *
-	 * If no die handler is given we will just bug() as a last resort.
+	 * If no die handler is given we will just power-off as a last resort.
 	 *
 	 * We could try disabling all associated rdevs - but we might shoot
 	 * ourselves in the head and leave the problematic regulator enabled. So

include/linux/regulator/driver.h

@@ -527,8 +527,8 @@ struct regulator_irq_data {
  *		active events as core does not clean the map data.
  *		REGULATOR_FAILED_RETRY can be returned to indicate that the
  *		status reading from IC failed. If this is repeated for
- *		fatal_cnt times the core will call die() callback or BUG()
- *		as a last resort to protect the HW.
+ *		fatal_cnt times the core will call die() callback or power-off
+ *		the system as a last resort to protect the HW.
  * @renable:	Optional callback to check status (if HW supports that) before
  *		re-enabling IRQ. If implemented this should clear the error
  *		flags so that errors fetched by regulator_get_error_flags()
@@ -537,7 +537,8 @@ struct regulator_irq_data {
  *		REGULATOR_FAILED_RETRY can be returned to
  *		indicate that the status reading from IC failed. If this is
  *		repeated for 'fatal_cnt' times the core will call die()
- *		callback or BUG() as a last resort to protect the HW.
+ *		callback or if die() is not populated then attempt to power-off
+ *		the system as a last resort to protect the HW.
  *		Returning zero indicates that the problem in HW has been solved
  *		and IRQ will be re-enabled. Returning REGULATOR_ERROR_ON
  *		indicates the error condition is still active and keeps IRQ