1 files changed, 27 insertions, 10 deletions

diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
index 6802596b017c..e9910b41d48e 100644
--- a/include/linux/iio/consumer.h
+++ b/include/linux/iio/consumer.h
@@ -201,8 +201,9 @@ struct iio_dev
  * @chan:		The channel being queried.
  * @val:		Value read back.
  *
- * Note raw reads from iio channels are in adc counts and hence
- * scale will need to be applied if standard units required.
+ * Note, if standard units are required, raw reads from iio channels
+ * need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
  */
 int iio_read_channel_raw(struct iio_channel *chan,
 			 int *val);
@@ -212,8 +213,9 @@ int iio_read_channel_raw(struct iio_channel *chan,
  * @chan:		The channel being queried.
  * @val:		Value read back.
  *
- * Note raw reads from iio channels are in adc counts and hence
- * scale will need to be applied if standard units required.
+ * Note, if standard units are required, raw reads from iio channels
+ * need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
  *
  * In opposit to the normal iio_read_channel_raw this function
  * returns the average of multiple reads.
@@ -281,8 +283,9 @@ int iio_read_channel_attribute(struct iio_channel *chan, int *val,
  * @chan:		The channel being queried.
  * @val:		Value being written.
  *
- * Note raw writes to iio channels are in dac counts and hence
- * scale will need to be applied if standard units required.
+ * Note that for raw writes to iio channels, if the value provided is
+ * in standard units, the affect of the scale and offset must be removed
+ * as (value / scale) - offset.
  */
 int iio_write_channel_raw(struct iio_channel *chan, int val);
 
@@ -292,12 +295,25 @@ int iio_write_channel_raw(struct iio_channel *chan, int val);
  * @chan:		The channel being queried.
  * @val:		Value read back.
  *
- * Note raw reads from iio channels are in adc counts and hence
- * scale will need to be applied if standard units are required.
+ * Note, if standard units are required, raw reads from iio channels
+ * need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
  */
 int iio_read_max_channel_raw(struct iio_channel *chan, int *val);
 
 /**
+ * iio_read_min_channel_raw() - read minimum available raw value from a given
+ *				channel, i.e. the minimum possible value.
+ * @chan:		The channel being queried.
+ * @val:		Value read back.
+ *
+ * Note, if standard units are required, raw reads from iio channels
+ * need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
+ */
+int iio_read_min_channel_raw(struct iio_channel *chan, int *val);
+
+/**
  * iio_read_avail_channel_raw() - read available raw values from a given channel
  * @chan:		The channel being queried.
  * @vals:		Available values read back.
@@ -308,8 +324,9 @@ int iio_read_max_channel_raw(struct iio_channel *chan, int *val);
  * For ranges, three vals are always returned; min, step and max.
  * For lists, all the possible values are enumerated.
  *
- * Note raw available values from iio channels are in adc counts and
- * hence scale will need to be applied if standard units are required.
+ * Note, if standard units are required, raw available values from iio
+ * channels need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
  */
 int iio_read_avail_channel_raw(struct iio_channel *chan,
 			       const int **vals, int *length);