[PATCH 1/2] device: Add dev_of_node() accessor

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

Suggested by Arnd Bergmann, this gives a practical accessor for
the of_node field of struct device while instructing the compiler
that it will be NULL if CONFIG_OF is not set.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

This is what we discussed back in November and I had forgotten
to finish :)

 include/linux/device.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/device.h b/include/linux/device.h
index fb50673..08128288 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -916,6 +916,13 @@ static inline void device_lock_assert(struct device *dev)
 	lockdep_assert_held(&dev->mutex);
 }
 
+static inline struct device_node *dev_of_node(struct device *dev)
+{
+	if (!IS_ENABLED(CONFIG_OF))
+		return NULL;
+	return dev->of_node;
+}
+
 void driver_init(void);
 
 /*