Regulator: Push lock out of _notifier_call_chain + add voltage change event.

Regulator: Push lock out of _notifier_call_chain and into caller functions
(side effect of fixing deadlock in regulator_force_disable)
+ Add a voltage changed event.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/drivers/regulator/wm8350-regulator.c b/drivers/regulator/wm8350-regulator.c
index 5056e23..afad611 100644
--- a/drivers/regulator/wm8350-regulator.c
+++ b/drivers/regulator/wm8350-regulator.c
@@ -1293,6 +1293,7 @@
 {
 	struct regulator_dev *rdev = (struct regulator_dev *)data;
 
+	mutex_lock(&rdev->mutex);
 	if (irq == WM8350_IRQ_CS1 || irq == WM8350_IRQ_CS2)
 		regulator_notifier_call_chain(rdev,
 					      REGULATOR_EVENT_REGULATION_OUT,
@@ -1301,6 +1302,7 @@
 		regulator_notifier_call_chain(rdev,
 					      REGULATOR_EVENT_UNDER_VOLTAGE,
 					      wm8350);
+	mutex_unlock(&rdev->mutex);
 }
 
 static int wm8350_regulator_probe(struct platform_device *pdev)