1 files changed, 74 insertions, 1 deletions
diff --git a/Documentation/iio/ad7380.rst b/Documentation/iio/ad7380.rst
index 6f70b49b9ef2..d51f9ee3e939 100644
--- a/Documentation/iio/ad7380.rst
+++ b/Documentation/iio/ad7380.rst
@@ -27,6 +27,10 @@ The following chips are supported by this driver:
 * `AD7386-4 <https://www.analog.com/en/products/ad7386-4.html>`_
 * `AD7387-4 <https://www.analog.com/en/products/ad7387-4.html>`_
 * `AD7388-4 <https://www.analog.com/en/products/ad7388-4.html>`_
+* `AD7389-4 <https://www.analog.com/en/products/ad7389-4.html>`_
+* `ADAQ4370-4 <https://www.analog.com/en/products/adaq4370-4.html>`_
+* `ADAQ4380-4 <https://www.analog.com/en/products/adaq4380-4.html>`_
+* `ADAQ4381-4 <https://www.analog.com/en/products/adaq4381-4.html>`_
 
 
 Supported features
@@ -47,6 +51,18 @@ ad7380-4
 ad7380-4 supports only an external reference voltage (2.5V to 3.3V). It must be
 declared in the device tree as ``refin-supply``.
 
+ad7389-4
+~~~~~~~~
+
+ad7389-4 supports only an internal reference voltage. ``refin-supply`` and
+``refio-supply`` properties are both omitted in this case.
+
+ADAQ devices
+~~~~~~~~~~~~
+
+ADAQ devices don't have an external reference, but use a 3.3V internal reference
+derived from one of its supplies (``refin-supply``)
+
 All other devices from ad738x family
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -84,6 +100,38 @@ must restart iiod using the following command:
 
 	root:~# systemctl restart iiod
 
+Alert
+-----
+
+2 channels variants of the ad738x family, can use the SDOB line as an alert pin
+when configured in 1 SDO line mode. 4 channels variants, can use SDOD as an
+alert pin when configured in 1 or 2 SDO line(s) mode, although only 1 SDO line
+mode is currently supported by the driver (see `SPI wiring modes`_).
+
+At the end of a conversion the active-low alert pin gets asserted if the
+conversion result exceeds the alert high limit or falls below the alert low
+limit. It is cleared, on a falling edge of CS. The alert pin is common to all
+channels.
+
+User can enable alert using the regular iio events attribute:
+
+.. code-block:: bash
+
+	events/thresh_either_en
+
+The high and low thresholds are common to all channels and can also be set using
+regular iio events attributes:
+
+.. code-block:: bash
+
+	events/in_thresh_falling_value
+	events/in_thresh_rising_value
+
+If debugfs is available, user can read the ALERT register to determine the
+faulty channel and direction.
+
+In most use cases, user will hardwire the alert pin to trigger a shutdown.
+
 Channel selection and sequencer (single-end chips only)
 -------------------------------------------------------
 
@@ -121,6 +169,14 @@ Example for AD7386/7/8 (2 channels parts):
 
 When enabling sequencer mode, the effective sampling rate is divided by two.
 
+Gain (ADAQ devices only)
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+ADAQ devices have a pin selectable gain in front of each ADC. The appropriate
+gain is selectable from device tree using the ``adi,gain-milli`` property.
+Refer to the typical connection diagrams section of the datasheet for pin
+wiring.
+
 Unimplemented features
 ----------------------
 
@@ -128,8 +184,25 @@ Unimplemented features
 - Rolling average oversampling
 - Power down mode
 - CRC indication
-- Alert
 
+SPI offload support
+===================
+
+To be able to achieve the maximum sample rate, the driver can be used with the
+`AXI SPI Engine`_ to provide SPI offload support.
+
+.. _AXI SPI Engine: http://analogdevicesinc.github.io/hdl/projects/pulsar_adc/index.html
+
+When SPI offload is being used, some attributes will be different.
+
+* ``trigger`` directory is removed.
+* ``in_voltage0_sampling_frequency`` attribute is added for setting the sample
+  rate.
+* ``in_voltage0_sampling_frequency_available`` attribute is added for querying
+  the max sample rate.
+* ``timestamp`` channel is removed.
+* Buffer data format may be different compared to when offload is not used,
+  e.g. the ``in_voltage0_type`` attribute.
 
 Device buffers
 ==============