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
 16static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = {
 17	.postenable = &iio_triggered_buffer_postenable,
 18	.predisable = &iio_triggered_buffer_predisable,
 19};
 20
 21/**
 22 * iio_triggered_buffer_setup() - Setup triggered buffer and pollfunc
 23 * @indio_dev:		IIO device structure
 24 * @h:			Function which will be used as pollfunc top half
 25 * @thread:		Function which will be used as pollfunc bottom half
 26 * @setup_ops:		Buffer setup functions to use for this device.
 27 *			If NULL the default setup functions for triggered
 28 *			buffers will be used.
 29 *
 30 * This function combines some common tasks which will normally be performed
 31 * when setting up a triggered buffer. It will allocate the buffer and the
 32 * pollfunc.
 33 *
 34 * Before calling this function the indio_dev structure should already be
 35 * completely initialized, but not yet registered. In practice this means that
 36 * this function should be called right before iio_device_register().
 37 *
 38 * To free the resources allocated by this function call
 39 * iio_triggered_buffer_cleanup().
 40 */
 41int iio_triggered_buffer_setup(struct iio_dev *indio_dev,
 42	irqreturn_t (*h)(int irq, void *p),
 43	irqreturn_t (*thread)(int irq, void *p),
 44	const struct iio_buffer_setup_ops *setup_ops)
 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	iio_device_attach_buffer(indio_dev, buffer);
 56
 57	indio_dev->pollfunc = iio_alloc_pollfunc(h,
 58						 thread,
 59						 IRQF_ONESHOT,
 60						 indio_dev,
 61						 "%s_consumer%d",
 62						 indio_dev->name,
 63						 indio_dev->id);
 64	if (indio_dev->pollfunc == NULL) {
 65		ret = -ENOMEM;
 66		goto error_kfifo_free;
 67	}
 68
 69	/* Ring buffer functions - here trigger setup related */
 70	if (setup_ops)
 71		indio_dev->setup_ops = setup_ops;
 72	else
 73		indio_dev->setup_ops = &iio_triggered_buffer_setup_ops;
 74
 75	/* Flag that polled ring buffering is possible */
 76	indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
 77
 78	return 0;
 79
 80error_kfifo_free:
 81	iio_kfifo_free(indio_dev->buffer);
 82error_ret:
 83	return ret;
 84}
 85EXPORT_SYMBOL(iio_triggered_buffer_setup);
 86
 87/**
 88 * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup()
 89 * @indio_dev: IIO device structure
 90 */
 91void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
 92{
 93	iio_dealloc_pollfunc(indio_dev->pollfunc);
 94	iio_kfifo_free(indio_dev->buffer);
 95}
 96EXPORT_SYMBOL(iio_triggered_buffer_cleanup);
 97
 98static void devm_iio_triggered_buffer_clean(struct device *dev, void *res)
 99{
100	iio_triggered_buffer_cleanup(*(struct iio_dev **)res);
101}
102
103int devm_iio_triggered_buffer_setup(struct device *dev,
104				    struct iio_dev *indio_dev,
105				    irqreturn_t (*h)(int irq, void *p),
106				    irqreturn_t (*thread)(int irq, void *p),
107				    const struct iio_buffer_setup_ops *ops)
108{
109	struct iio_dev **ptr;
110	int ret;
111
112	ptr = devres_alloc(devm_iio_triggered_buffer_clean, sizeof(*ptr),
113			   GFP_KERNEL);
114	if (!ptr)
115		return -ENOMEM;
116
117	*ptr = indio_dev;
118
119	ret = iio_triggered_buffer_setup(indio_dev, h, thread, ops);
120	if (!ret)
121		devres_add(dev, ptr);
122	else
123		devres_free(ptr);
124
125	return ret;
126}
127EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup);
128
129void devm_iio_triggered_buffer_cleanup(struct device *dev,
130				       struct iio_dev *indio_dev)
131{
132	int rc;
133
134	rc = devres_release(dev, devm_iio_triggered_buffer_clean,
135			    devm_iio_device_match, indio_dev);
136	WARN_ON(rc);
137}
138EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_cleanup);
139
140MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
141MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
142MODULE_LICENSE("GPL");