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/buffer_impl.h>
 13#include <linux/iio/kfifo_buf.h>
 14#include <linux/iio/triggered_buffer.h>
 15#include <linux/iio/trigger_consumer.h>
 16
 17/**
 18 * iio_triggered_buffer_setup_ext() - Setup triggered buffer and pollfunc
 19 * @indio_dev:		IIO device structure
 20 * @h:			Function which will be used as pollfunc top half
 21 * @thread:		Function which will be used as pollfunc bottom half
 22 * @direction:		Direction of the data stream (in/out).
 23 * @setup_ops:		Buffer setup functions to use for this device.
 24 *			If NULL the default setup functions for triggered
 25 *			buffers will be used.
 26 * @buffer_attrs:	Extra sysfs buffer attributes for this IIO buffer
 27 *
 28 * This function combines some common tasks which will normally be performed
 29 * when setting up a triggered buffer. It will allocate the buffer and the
 30 * pollfunc.
 31 *
 32 * Before calling this function the indio_dev structure should already be
 33 * completely initialized, but not yet registered. In practice this means that
 34 * this function should be called right before iio_device_register().
 35 *
 36 * To free the resources allocated by this function call
 37 * iio_triggered_buffer_cleanup().
 38 */
 39int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev,
 40	irqreturn_t (*h)(int irq, void *p),
 41	irqreturn_t (*thread)(int irq, void *p),
 42	enum iio_buffer_direction direction,
 43	const struct iio_buffer_setup_ops *setup_ops,
 44	const struct iio_dev_attr **buffer_attrs)
 45{
 46	struct iio_buffer *buffer;
 47	int ret;
 48
 49	buffer = iio_kfifo_allocate();
 50	if (!buffer) {
 51		ret = -ENOMEM;
 52		goto error_ret;
 53	}
 54
 55	indio_dev->pollfunc = iio_alloc_pollfunc(h,
 56						 thread,
 57						 IRQF_ONESHOT,
 58						 indio_dev,
 59						 "%s_consumer%d",
 60						 indio_dev->name,
 61						 iio_device_id(indio_dev));
 62	if (indio_dev->pollfunc == NULL) {
 63		ret = -ENOMEM;
 64		goto error_kfifo_free;
 65	}
 66
 67	/* Ring buffer functions - here trigger setup related */
 68	indio_dev->setup_ops = setup_ops;
 69
 70	/* Flag that polled ring buffering is possible */
 71	indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
 72
 73	buffer->direction = direction;
 74	buffer->attrs = buffer_attrs;
 75
 76	ret = iio_device_attach_buffer(indio_dev, buffer);
 77	if (ret < 0)
 78		goto error_dealloc_pollfunc;
 79
 80	return 0;
 81
 82error_dealloc_pollfunc:
 83	iio_dealloc_pollfunc(indio_dev->pollfunc);
 84error_kfifo_free:
 85	iio_kfifo_free(buffer);
 86error_ret:
 87	return ret;
 88}
 89EXPORT_SYMBOL(iio_triggered_buffer_setup_ext);
 90
 91/**
 92 * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup_ext()
 93 * @indio_dev: IIO device structure
 94 */
 95void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
 96{
 97	iio_dealloc_pollfunc(indio_dev->pollfunc);
 98	iio_kfifo_free(indio_dev->buffer);
 99}
100EXPORT_SYMBOL(iio_triggered_buffer_cleanup);
101
102static void devm_iio_triggered_buffer_clean(void *indio_dev)
103{
104	iio_triggered_buffer_cleanup(indio_dev);
105}
106
107int devm_iio_triggered_buffer_setup_ext(struct device *dev,
108					struct iio_dev *indio_dev,
109					irqreturn_t (*h)(int irq, void *p),
110					irqreturn_t (*thread)(int irq, void *p),
111					enum iio_buffer_direction direction,
112					const struct iio_buffer_setup_ops *ops,
113					const struct iio_dev_attr **buffer_attrs)
114{
115	int ret;
116
117	ret = iio_triggered_buffer_setup_ext(indio_dev, h, thread, direction,
118					     ops, buffer_attrs);
119	if (ret)
120		return ret;
121
122	return devm_add_action_or_reset(dev, devm_iio_triggered_buffer_clean,
123					indio_dev);
124}
125EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup_ext);
126
127MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
128MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
129MODULE_LICENSE("GPL");