[PATCH 01/24] iio: Add dev_to_iio_dev() helper function

[Lars-Peter Clausen <lars@metafoo.de>]

This patch adds a helper function for retriving a iio_dev struct from a device
struct. Currently we open-code this in two different ways. One is using
dev_get_drvdata on the device and the other is using container_of. The new
helper function uses the container_of solution as it creates slightly smaller
code and also will eventually free up the drvdata pointer for usage by invidual
drivers.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 include/linux/iio/iio.h |   11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index eff2a39..38baea5 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -412,6 +412,17 @@ int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
 
 extern struct bus_type iio_bus_type;
 
+/**
+ * dev_to_iio_dev() - Get IIO device struct from a device struct
+ * @dev: The device embedded in the IIO device
+ *
+ * Note: The device must be a IIO device, otherwise the result is undefined.
+ */
+static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
+{
+	return container_of(dev, struct iio_dev, dev);
+}
+
 /* Can we make this smaller? */
 #define IIO_ALIGN L1_CACHE_BYTES
 /**
-- 
1.7.10