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	Add resource managed devm_iio_triggered_buffer_setup() and devm_iio_triggered_buffer_cleanup() to automatically clean up triggered buffers setup by IIO drivers, thus leading to simplified IIO drivers code. Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
		
			
				
	
	
		
			145 lines
		
	
	
	
		
			4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			145 lines
		
	
	
	
		
			4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
 /*
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 * Copyright (c) 2012 Analog Devices, Inc.
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 *  Author: Lars-Peter Clausen <lars@metafoo.de>
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 *
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 * This program is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 as published by
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 * the Free Software Foundation.
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 */
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#include <linux/kernel.h>
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#include <linux/export.h>
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#include <linux/module.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/buffer.h>
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#include <linux/iio/kfifo_buf.h>
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#include <linux/iio/triggered_buffer.h>
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#include <linux/iio/trigger_consumer.h>
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static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = {
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	.postenable = &iio_triggered_buffer_postenable,
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	.predisable = &iio_triggered_buffer_predisable,
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};
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/**
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 * iio_triggered_buffer_setup() - Setup triggered buffer and pollfunc
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 * @indio_dev:		IIO device structure
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 * @h:			Function which will be used as pollfunc top half
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 * @thread:		Function which will be used as pollfunc bottom half
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 * @setup_ops:		Buffer setup functions to use for this device.
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 *			If NULL the default setup functions for triggered
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 *			buffers will be used.
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 *
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 * This function combines some common tasks which will normally be performed
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 * when setting up a triggered buffer. It will allocate the buffer and the
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 * pollfunc.
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 *
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 * Before calling this function the indio_dev structure should already be
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 * completely initialized, but not yet registered. In practice this means that
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 * this function should be called right before iio_device_register().
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 *
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 * To free the resources allocated by this function call
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 * iio_triggered_buffer_cleanup().
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 */
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int iio_triggered_buffer_setup(struct iio_dev *indio_dev,
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	irqreturn_t (*h)(int irq, void *p),
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	irqreturn_t (*thread)(int irq, void *p),
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	const struct iio_buffer_setup_ops *setup_ops)
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{
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	struct iio_buffer *buffer;
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	int ret;
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	buffer = iio_kfifo_allocate();
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	if (!buffer) {
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		ret = -ENOMEM;
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		goto error_ret;
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	}
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	iio_device_attach_buffer(indio_dev, buffer);
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	indio_dev->pollfunc = iio_alloc_pollfunc(h,
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						 thread,
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						 IRQF_ONESHOT,
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						 indio_dev,
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						 "%s_consumer%d",
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						 indio_dev->name,
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						 indio_dev->id);
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	if (indio_dev->pollfunc == NULL) {
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		ret = -ENOMEM;
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		goto error_kfifo_free;
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	}
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	/* Ring buffer functions - here trigger setup related */
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	if (setup_ops)
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		indio_dev->setup_ops = setup_ops;
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	else
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		indio_dev->setup_ops = &iio_triggered_buffer_setup_ops;
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	/* Flag that polled ring buffering is possible */
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	indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
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	return 0;
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error_kfifo_free:
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	iio_kfifo_free(indio_dev->buffer);
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error_ret:
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	return ret;
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}
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EXPORT_SYMBOL(iio_triggered_buffer_setup);
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/**
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 * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup()
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 * @indio_dev: IIO device structure
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 */
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void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
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{
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	iio_dealloc_pollfunc(indio_dev->pollfunc);
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	iio_kfifo_free(indio_dev->buffer);
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}
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EXPORT_SYMBOL(iio_triggered_buffer_cleanup);
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static void devm_iio_triggered_buffer_clean(struct device *dev, void *res)
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{
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	iio_triggered_buffer_cleanup(*(struct iio_dev **)res);
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}
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int devm_iio_triggered_buffer_setup(struct device *dev,
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				    struct iio_dev *indio_dev,
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				    irqreturn_t (*h)(int irq, void *p),
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				    irqreturn_t (*thread)(int irq, void *p),
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				    const struct iio_buffer_setup_ops *ops)
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{
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	struct iio_dev **ptr;
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	int ret;
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	ptr = devres_alloc(devm_iio_triggered_buffer_clean, sizeof(*ptr),
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			   GFP_KERNEL);
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	if (!ptr)
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		return -ENOMEM;
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	*ptr = indio_dev;
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	ret = iio_triggered_buffer_setup(indio_dev, h, thread, ops);
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	if (!ret)
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		devres_add(dev, ptr);
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	else
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		devres_free(ptr);
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	return ret;
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}
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EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup);
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void devm_iio_triggered_buffer_cleanup(struct device *dev,
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				       struct iio_dev *indio_dev)
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{
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	int rc;
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	rc = devres_release(dev, devm_iio_triggered_buffer_clean,
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			    devm_iio_device_match, indio_dev);
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	WARN_ON(rc);
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}
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EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_cleanup);
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MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
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MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
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MODULE_LICENSE("GPL");
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