1// SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2012 Analog Devices, Inc.
4 *  Author: Lars-Peter Clausen <lars@metafoo.de>
5 */
6
7#include <linux/kernel.h>
8#include <linux/export.h>
9#include <linux/module.h>
10#include <linux/iio/iio.h>
11#include <linux/iio/buffer.h>
12#include <linux/iio/kfifo_buf.h>
13#include <linux/iio/triggered_buffer.h>
14#include <linux/iio/trigger_consumer.h>
15
16/**
17 * iio_triggered_buffer_setup() - Setup triggered buffer and pollfunc
18 * @indio_dev:		IIO device structure
19 * @h:			Function which will be used as pollfunc top half
20 * @thread:		Function which will be used as pollfunc bottom half
21 * @setup_ops:		Buffer setup functions to use for this device.
22 *			If NULL the default setup functions for triggered
23 *			buffers will be used.
24 *
25 * This function combines some common tasks which will normally be performed
26 * when setting up a triggered buffer. It will allocate the buffer and the
27 * pollfunc.
28 *
29 * Before calling this function the indio_dev structure should already be
30 * completely initialized, but not yet registered. In practice this means that
31 * this function should be called right before iio_device_register().
32 *
33 * To free the resources allocated by this function call
34 * iio_triggered_buffer_cleanup().
35 */
36int iio_triggered_buffer_setup(struct iio_dev *indio_dev,
37	irqreturn_t (*h)(int irq, void *p),
38	irqreturn_t (*thread)(int irq, void *p),
39	const struct iio_buffer_setup_ops *setup_ops)
40{
41	struct iio_buffer *buffer;
42	int ret;
43
44	buffer = iio_kfifo_allocate();
45	if (!buffer) {
46		ret = -ENOMEM;
47		goto error_ret;
48	}
49
50	iio_device_attach_buffer(indio_dev, buffer);
51
52	indio_dev->pollfunc = iio_alloc_pollfunc(h,
53						 thread,
54						 IRQF_ONESHOT,
55						 indio_dev,
56						 "%s_consumer%d",
57						 indio_dev->name,
58						 indio_dev->id);
59	if (indio_dev->pollfunc == NULL) {
60		ret = -ENOMEM;
61		goto error_kfifo_free;
62	}
63
64	/* Ring buffer functions - here trigger setup related */
65	indio_dev->setup_ops = setup_ops;
66
67	/* Flag that polled ring buffering is possible */
68	indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
69
70	return 0;
71
72error_kfifo_free:
73	iio_kfifo_free(indio_dev->buffer);
74error_ret:
75	return ret;
76}
77EXPORT_SYMBOL(iio_triggered_buffer_setup);
78
79/**
80 * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup()
81 * @indio_dev: IIO device structure
82 */
83void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
84{
85	iio_dealloc_pollfunc(indio_dev->pollfunc);
86	iio_kfifo_free(indio_dev->buffer);
87}
88EXPORT_SYMBOL(iio_triggered_buffer_cleanup);
89
90static void devm_iio_triggered_buffer_clean(struct device *dev, void *res)
91{
92	iio_triggered_buffer_cleanup(*(struct iio_dev **)res);
93}
94
95int devm_iio_triggered_buffer_setup(struct device *dev,
96				    struct iio_dev *indio_dev,
97				    irqreturn_t (*h)(int irq, void *p),
98				    irqreturn_t (*thread)(int irq, void *p),
99				    const struct iio_buffer_setup_ops *ops)
100{
101	struct iio_dev **ptr;
102	int ret;
103
104	ptr = devres_alloc(devm_iio_triggered_buffer_clean, sizeof(*ptr),
105			   GFP_KERNEL);
106	if (!ptr)
107		return -ENOMEM;
108
109	*ptr = indio_dev;
110
111	ret = iio_triggered_buffer_setup(indio_dev, h, thread, ops);
112	if (!ret)
113		devres_add(dev, ptr);
114	else
115		devres_free(ptr);
116
117	return ret;
118}
119EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup);
120
121MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
122MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
123MODULE_LICENSE("GPL");
124