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1// SPDX-License-Identifier: GPL-2.0-only2 /*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 pollfunc19 * @indio_dev: IIO device structure20 * @h: Function which will be used as pollfunc top half21 * @thread: Function which will be used as pollfunc bottom half22 * @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 triggered25 * buffers will be used.26 * @buffer_attrs: Extra sysfs buffer attributes for this IIO buffer27 *28 * This function combines some common tasks which will normally be performed29 * when setting up a triggered buffer. It will allocate the buffer and the30 * pollfunc.31 *32 * Before calling this function the indio_dev structure should already be33 * completely initialized, but not yet registered. In practice this means that34 * this function should be called right before iio_device_register().35 *36 * To free the resources allocated by this function call37 * 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 /*50 * iio_triggered_buffer_cleanup() assumes that the buffer allocated here51 * is assigned to indio_dev->buffer but this is only the case if this52 * function is the first caller to iio_device_attach_buffer(). If53 * indio_dev->buffer is already set then we can't proceed otherwise the54 * cleanup function will try to free a buffer that was not allocated here.55 */56 if (indio_dev->buffer)57 return -EADDRINUSE;58 59 buffer = iio_kfifo_allocate();60 if (!buffer) {61 ret = -ENOMEM;62 goto error_ret;63 }64 65 indio_dev->pollfunc = iio_alloc_pollfunc(h,66 thread,67 IRQF_ONESHOT,68 indio_dev,69 "%s_consumer%d",70 indio_dev->name,71 iio_device_id(indio_dev));72 if (indio_dev->pollfunc == NULL) {73 ret = -ENOMEM;74 goto error_kfifo_free;75 }76 77 /* Ring buffer functions - here trigger setup related */78 indio_dev->setup_ops = setup_ops;79 80 /* Flag that polled ring buffering is possible */81 indio_dev->modes |= INDIO_BUFFER_TRIGGERED;82 83 buffer->direction = direction;84 buffer->attrs = buffer_attrs;85 86 ret = iio_device_attach_buffer(indio_dev, buffer);87 if (ret < 0)88 goto error_dealloc_pollfunc;89 90 return 0;91 92error_dealloc_pollfunc:93 iio_dealloc_pollfunc(indio_dev->pollfunc);94error_kfifo_free:95 iio_kfifo_free(buffer);96error_ret:97 return ret;98}99EXPORT_SYMBOL(iio_triggered_buffer_setup_ext);100 101/**102 * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup_ext()103 * @indio_dev: IIO device structure104 */105void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)106{107 iio_dealloc_pollfunc(indio_dev->pollfunc);108 iio_kfifo_free(indio_dev->buffer);109}110EXPORT_SYMBOL(iio_triggered_buffer_cleanup);111 112static void devm_iio_triggered_buffer_clean(void *indio_dev)113{114 iio_triggered_buffer_cleanup(indio_dev);115}116 117int devm_iio_triggered_buffer_setup_ext(struct device *dev,118 struct iio_dev *indio_dev,119 irqreturn_t (*h)(int irq, void *p),120 irqreturn_t (*thread)(int irq, void *p),121 enum iio_buffer_direction direction,122 const struct iio_buffer_setup_ops *ops,123 const struct iio_dev_attr **buffer_attrs)124{125 int ret;126 127 ret = iio_triggered_buffer_setup_ext(indio_dev, h, thread, direction,128 ops, buffer_attrs);129 if (ret)130 return ret;131 132 return devm_add_action_or_reset(dev, devm_iio_triggered_buffer_clean,133 indio_dev);134}135EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup_ext);136 137MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");138MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");139MODULE_LICENSE("GPL");140