linux/Documentation/driver-api/iio/hw-consumer.rst

===========
HW consumer
===========
An IIO device can be directly connected to another device in hardware. In this
case the buffers between IIO provider and IIO consumer are handled by hardware.
The Industrial I/O HW consumer offers a way to bond these IIO devices without
software buffer for data. The implementation can be found under
:file:`drivers/iio/buffer/hw-consumer.c`


* struct :c:type:`iio_hw_consumer` — Hardware consumer structure
* :c:func:`iio_hw_consumer_alloc` — Allocate IIO hardware consumer
* :c:func:`iio_hw_consumer_free` — Free IIO hardware consumer
* :c:func:`iio_hw_consumer_enable` — Enable IIO hardware consumer
* :c:func:`iio_hw_consumer_disable` — Disable IIO hardware consumer


HW consumer setup
=================

As standard IIO device the implementation is based on IIO provider/consumer.
A typical IIO HW consumer setup looks like this::

	static struct iio_hw_consumer *hwc;

	static const struct iio_info adc_info = {
		.read_raw = adc_read_raw,
	};

	static int adc_read_raw(struct iio_dev *indio_dev,
				struct iio_chan_spec const *chan, int *val,
				int *val2, long mask)
	{
		ret = iio_hw_consumer_enable(hwc);

		/* Acquire data */

		ret = iio_hw_consumer_disable(hwc);
	}

	static int adc_probe(struct platform_device *pdev)
	{
		hwc = devm_iio_hw_consumer_alloc(&iio->dev);
	}

More details
============
.. kernel-doc:: include/linux/iio/hw-consumer.h
.. kernel-doc:: drivers/iio/buffer/industrialio-hw-consumer.c
   :export: