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