[PATCH 2/4] iio: add iio_channel_cb_get_iio_buffer helper

[Artur Rojek]

Introduce a helper function to retrieve an iio_buffer from
iio_cb_buffer.

This is useful for consumers that need to extract metadata about
the buffer, e.g. get the channel offsets.

Tested-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
Signed-off-by: Artur Rojek <contact@xxxxxxxxxxxxxx>
---
 drivers/iio/buffer/industrialio-buffer-cb.c |  7 +++++++
 include/linux/iio/consumer.h                | 12 ++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/drivers/iio/buffer/industrialio-buffer-cb.c b/drivers/iio/buffer/industrialio-buffer-cb.c
index 4c12b7a94af5..47d6e28b4d36 100644
--- a/drivers/iio/buffer/industrialio-buffer-cb.c
+++ b/drivers/iio/buffer/industrialio-buffer-cb.c
@@ -151,6 +151,13 @@ struct iio_dev
 }
 EXPORT_SYMBOL_GPL(iio_channel_cb_get_iio_dev);
 
+struct iio_buffer
+*iio_channel_cb_get_iio_buffer(struct iio_cb_buffer *cb_buffer)
+{
+	return &cb_buffer->buffer;
+}
+EXPORT_SYMBOL_GPL(iio_channel_cb_get_iio_buffer);
+
 MODULE_AUTHOR("Jonathan Cameron <jic23@xxxxxxxxxx>");
 MODULE_DESCRIPTION("Industrial I/O callback buffer");
 MODULE_LICENSE("GPL");
diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
index 6802596b017c..c28925d5b69c 100644
--- a/include/linux/iio/consumer.h
+++ b/include/linux/iio/consumer.h
@@ -196,6 +196,18 @@ struct iio_channel
 struct iio_dev
 *iio_channel_cb_get_iio_dev(const struct iio_cb_buffer *cb_buffer);
 
+/**
+ * iio_channel_cb_get_iio_buffer() - get access to the underlying buffer.
+ * @cb_buffer:		The callback buffer from whom we want the buffer
+ *			information.
+ *
+ * This function allows one to obtain information about the buffer.
+ * The primary aim is to allow drivers that are consuming a buffer to query
+ * things like channel offsets in the buffer.
+ */
+struct iio_buffer
+*iio_channel_cb_get_iio_buffer(struct iio_cb_buffer *cb_buffer);
+
 /**
  * iio_read_channel_raw() - read from a given channel
  * @chan:		The channel being queried.
-- 
2.37.2