staging:iio:in kernel users: Add a data field for channel specific info.

Used to allow information about a given channel mapping to be passed
through from board files to the consumer drivers.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/include/linux/iio/machine.h b/include/linux/iio/machine.h
index 809a3f0..1601a2a 100644
--- a/include/linux/iio/machine.h
+++ b/include/linux/iio/machine.h
@@ -19,11 +19,13 @@
  * @consumer_dev_name:	Name to uniquely identify the consumer device.
  * @consumer_channel:	Unique name used to identify the channel on the
  *			consumer side.
+ * @consumer_data:	Data about the channel for use by the consumer driver.
  */
 struct iio_map {
 	const char *adc_channel_label;
 	const char *consumer_dev_name;
 	const char *consumer_channel;
+	void *consumer_data;
 };
 
 #endif