Documentation/iio/ad7944.rst

File Facts

System

Linux kernel

Corpus path

Documentation/iio/ad7944.rst

Extension

.rst

Size

7247 bytes

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179

Domain

Support Tooling And Documentation

Bucket

Documentation

Inferred role

Support Tooling And Documentation: documentation

Status

atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

• Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

• No C-style include directives detected by the generator.

Detected Declarations

• No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

.. SPDX-License-Identifier: GPL-2.0-only

=============
AD7944 driver
=============

ADC driver for Analog Devices Inc. AD7944 and similar devices. The module name
is ``ad7944``.


Supported devices
=================

The following chips are supported by this driver:

* `AD7944 <https://www.analog.com/AD7944>`_
* `AD7985 <https://www.analog.com/AD7985>`_
* `AD7986 <https://www.analog.com/AD7986>`_


Supported features
==================

SPI wiring modes
----------------

The driver currently supports three of the many possible SPI wiring configurations.

CS mode, 3-wire, without busy indicator
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. code-block::

                                         +-------------+
                    +--------------------| CS          |
                    v                    |             |
    VIO   +--------------------+         |     HOST    |
     |    |        CNV         |         |             |
     +--->| SDI   AD7944   SDO |-------->| SDI         |
          |        SCK         |         |             |
          +--------------------+         |             |
                    ^                    |             |
                    +--------------------| SCLK        |
                                         +-------------+

To select this mode in the device tree, set the ``adi,spi-mode`` property to
``"single"`` and omit the ``cnv-gpios`` property.

This is the only wiring configuration supported when using `SPI offload support`_.

CS mode, 4-wire, without busy indicator
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. code-block::

                                         +-------------+
     +-----------------------------------| CS          |
     |                                   |             |
     |              +--------------------| GPIO        |
     |              v                    |             |
     |    +--------------------+         |     HOST    |
     |    |        CNV         |         |             |
     +--->| SDI   AD7944   SDO |-------->| SDI         |
          |        SCK         |         |             |
          +--------------------+         |             |
                    ^                    |             |
                    +--------------------| SCLK        |
                                         +-------------+

To select this mode in the device tree, omit the ``adi,spi-mode`` property and

Annotation

• Atlas domain: Support Tooling And Documentation / Documentation.
• Implementation status: atlas-only.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.