regulator: mc13xxx: Fix NULL pointer error in non-DT mode

Add a check to avoid NULL pointer dereference error when
booted in non-DT mode. While at it also remove the additional
of_node_get which is no longer needed for of_get_child_by_name
and fix the node pointer.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Reported-by: Philippe Rétornaz <philippe.retornaz@epfl.ch>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/regulator/mc13xxx-regulator-core.c b/drivers/regulator/mc13xxx-regulator-core.c
index 4498a3f..bf75fca 100644
--- a/drivers/regulator/mc13xxx-regulator-core.c
+++ b/drivers/regulator/mc13xxx-regulator-core.c
@@ -167,8 +167,10 @@
 	struct device_node *parent;
 	int num;
 
-	of_node_get(pdev->dev.parent->of_node);
-	parent = of_get_child_by_name(pdev->dev.parent->of_node, "regulators");
+	if (!pdev->dev.of_node)
+		return -ENODEV;
+
+	parent = of_get_child_by_name(pdev->dev.of_node, "regulators");
 	if (!parent)
 		return -ENODEV;
 
@@ -187,8 +189,10 @@
 	struct device_node *parent, *child;
 	int i, parsed = 0;
 
-	of_node_get(pdev->dev.parent->of_node);
-	parent = of_get_child_by_name(pdev->dev.parent->of_node, "regulators");
+	if (!pdev->dev.of_node)
+		return NULL;
+
+	parent = of_get_child_by_name(pdev->dev.of_node, "regulators");
 	if (!parent)
 		return NULL;