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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2012 Analog Devices, Inc.
* Author: Lars-Peter Clausen <lars@metafoo.de>
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/buffer_impl.h>
#include <linux/iio/kfifo_buf.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>
/**
* iio_triggered_buffer_setup_ext() - Setup triggered buffer and pollfunc
* @indio_dev: IIO device structure
* @h: Function which will be used as pollfunc top half
* @thread: Function which will be used as pollfunc bottom half
* @direction: Direction of the data stream (in/out).
* @setup_ops: Buffer setup functions to use for this device.
* If NULL the default setup functions for triggered
* buffers will be used.
* @buffer_attrs: Extra sysfs buffer attributes for this IIO buffer
*
* This function combines some common tasks which will normally be performed
* when setting up a triggered buffer. It will allocate the buffer and the
* pollfunc.
*
* Before calling this function the indio_dev structure should already be
* completely initialized, but not yet registered. In practice this means that
* this function should be called right before iio_device_register().
*
* To free the resources allocated by this function call
* iio_triggered_buffer_cleanup().
*/
int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev,
irqreturn_t (*h)(int irq, void *p),
irqreturn_t (*thread)(int irq, void *p),
enum iio_buffer_direction direction,
const struct iio_buffer_setup_ops *setup_ops,
const struct iio_dev_attr **buffer_attrs)
{
struct iio_buffer *buffer;
int ret;
/*
* iio_triggered_buffer_cleanup() assumes that the buffer allocated here
* is assigned to indio_dev->buffer but this is only the case if this
* function is the first caller to iio_device_attach_buffer(). If
* indio_dev->buffer is already set then we can't proceed otherwise the
* cleanup function will try to free a buffer that was not allocated here.
*/
if (indio_dev->buffer)
return -EADDRINUSE;
buffer = iio_kfifo_allocate();
if (!buffer) {
ret = -ENOMEM;
goto error_ret;
}
indio_dev->pollfunc = iio_alloc_pollfunc(h,
thread,
IRQF_ONESHOT,
indio_dev,
"%s_consumer%d",
indio_dev->name,
iio_device_id(indio_dev));
if (indio_dev->pollfunc == NULL) {
ret = -ENOMEM;
goto error_kfifo_free;
}
/* Ring buffer functions - here trigger setup related */
indio_dev->setup_ops = setup_ops;
/* Flag that polled ring buffering is possible */
indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
buffer->direction = direction;
buffer->attrs = buffer_attrs;
ret = iio_device_attach_buffer(indio_dev, buffer);
if (ret < 0)
goto error_dealloc_pollfunc;
return 0;
error_dealloc_pollfunc:
iio_dealloc_pollfunc(indio_dev->pollfunc);
error_kfifo_free:
iio_kfifo_free(buffer);
error_ret:
return ret;
}
EXPORT_SYMBOL(iio_triggered_buffer_setup_ext);
/**
* iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup_ext()
* @indio_dev: IIO device structure
*/
void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
{
iio_dealloc_pollfunc(indio_dev->pollfunc);
iio_kfifo_free(indio_dev->buffer);
}
EXPORT_SYMBOL(iio_triggered_buffer_cleanup);
static void devm_iio_triggered_buffer_clean(void *indio_dev)
{
iio_triggered_buffer_cleanup(indio_dev);
}
int devm_iio_triggered_buffer_setup_ext(struct device *dev,
struct iio_dev *indio_dev,
irqreturn_t (*h)(int irq, void *p),
irqreturn_t (*thread)(int irq, void *p),
enum iio_buffer_direction direction,
const struct iio_buffer_setup_ops *ops,
const struct iio_dev_attr **buffer_attrs)
{
int ret;
ret = iio_triggered_buffer_setup_ext(indio_dev, h, thread, direction,
ops, buffer_attrs);
if (ret)
return ret;
return devm_add_action_or_reset(dev, devm_iio_triggered_buffer_clean,
indio_dev);
}
EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup_ext);
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
MODULE_LICENSE("GPL");
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