Merge branch 'old.dcache' into work.dcache
[sfrench/cifs-2.6.git] / Documentation / driver-api / iio / hw-consumer.rst
1 ===========
2 HW consumer
3 ===========
4 An IIO device can be directly connected to another device in hardware. in this
5 case the buffers between IIO provider and IIO consumer are handled by hardware.
6 The Industrial I/O HW consumer offers a way to bond these IIO devices without
7 software buffer for data. The implementation can be found under
8 :file:`drivers/iio/buffer/hw-consumer.c`
9
10
11 * struct :c:type:`iio_hw_consumer` — Hardware consumer structure
12 * :c:func:`iio_hw_consumer_alloc` — Allocate IIO hardware consumer
13 * :c:func:`iio_hw_consumer_free` — Free IIO hardware consumer
14 * :c:func:`iio_hw_consumer_enable` — Enable IIO hardware consumer
15 * :c:func:`iio_hw_consumer_disable` — Disable IIO hardware consumer
16
17
18 HW consumer setup
19 =================
20
21 As standard IIO device the implementation is based on IIO provider/consumer.
22 A typical IIO HW consumer setup looks like this::
23
24         static struct iio_hw_consumer *hwc;
25
26         static const struct iio_info adc_info = {
27                 .read_raw = adc_read_raw,
28         };
29
30         static int adc_read_raw(struct iio_dev *indio_dev,
31                                 struct iio_chan_spec const *chan, int *val,
32                                 int *val2, long mask)
33         {
34                 ret = iio_hw_consumer_enable(hwc);
35
36                 /* Acquire data */
37
38                 ret = iio_hw_consumer_disable(hwc);
39         }
40
41         static int adc_probe(struct platform_device *pdev)
42         {
43                 hwc = devm_iio_hw_consumer_alloc(&iio->dev);
44         }
45
46 More details
47 ============
48 .. kernel-doc:: include/linux/iio/hw-consumer.h
49 .. kernel-doc:: drivers/iio/buffer/industrialio-hw-consumer.c
50    :export:
51