From mboxrd@z Thu Jan  1 00:00:00 1970
From: jic23@kernel.org (Jonathan Cameron)
Date: Sat, 2 Dec 2017 14:51:37 +0000
Subject: [PATCH v6 02/13] docs: driver-api: add iio hw consumer section
In-Reply-To: <1512150020-20335-3-git-send-email-arnaud.pouliquen@st.com>
References: <1512150020-20335-1-git-send-email-arnaud.pouliquen@st.com>
 <1512150020-20335-3-git-send-email-arnaud.pouliquen@st.com>
Message-ID: <20171202145137.159e7a0e@archlinux>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Fri, 1 Dec 2017 18:40:09 +0100
Arnaud Pouliquen <arnaud.pouliquen@st.com> wrote:

> This adds a section about the Hardware consumer
> API of the IIO subsystem to the driver API
> documentation.
> 
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  Documentation/driver-api/iio/hw-consumer.rst | 51 ++++++++++++++++++++++++++++
>  Documentation/driver-api/iio/index.rst       |  1 +
>  2 files changed, 52 insertions(+)
>  create mode 100644 Documentation/driver-api/iio/hw-consumer.rst
> 
> diff --git a/Documentation/driver-api/iio/hw-consumer.rst b/Documentation/driver-api/iio/hw-consumer.rst
> new file mode 100644
> index 0000000..8facce6
> --- /dev/null
> +++ b/Documentation/driver-api/iio/hw-consumer.rst
> @@ -0,0 +1,51 @@
> +===========
> +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:
> +
> diff --git a/Documentation/driver-api/iio/index.rst b/Documentation/driver-api/iio/index.rst
> index e5c3922..7fba341 100644
> --- a/Documentation/driver-api/iio/index.rst
> +++ b/Documentation/driver-api/iio/index.rst
> @@ -15,3 +15,4 @@ Contents:
>     buffers
>     triggers
>     triggered-buffers
> +   hw-consumer