#include <linux/kernel.h>#include <linux/slab.h>#include <linux/err.h>#include <linux/export.h>#include <linux/iio/buffer.h>#include <linux/iio/consumer.h> struct iio_cb_buffer {	struct iio_buffer buffer;	int (*cb)(const void *data, void *private);	void *private;	struct iio_channel *channels;}; static struct iio_cb_buffer *buffer_to_cb_buffer(struct iio_buffer *buffer){	return container_of(buffer, struct iio_cb_buffer, buffer);} static int iio_buffer_cb_store_to(struct iio_buffer *buffer, const void *data){	struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);	return cb_buff->cb(data, cb_buff->private);} static void iio_buffer_cb_release(struct iio_buffer *buffer){	struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);	kfree(cb_buff->buffer.scan_mask);	kfree(cb_buff);} static const struct iio_buffer_access_funcs iio_cb_access = {	.store_to = &iio_buffer_cb_store_to,	.release = &iio_buffer_cb_release,}; struct iio_cb_buffer *iio_channel_get_all_cb(struct device *dev,					     int (*cb)(const void *data,						       void *private),					     void *private){	int ret;	struct iio_cb_buffer *cb_buff;	struct iio_dev *indio_dev;	struct iio_channel *chan; 	cb_buff = kzalloc(sizeof(*cb_buff), GFP_KERNEL);	if (cb_buff == NULL) {		ret = -ENOMEM;		goto error_ret;	} 	iio_buffer_init(&cb_buff->buffer); 	cb_buff->private = private;	cb_buff->cb = cb;	cb_buff->buffer.access = &iio_cb_access;	INIT_LIST_HEAD(&cb_buff->buffer.demux_list); 	cb_buff->channels = iio_channel_get_all(dev);	if (IS_ERR(cb_buff->channels)) {		ret = PTR_ERR(cb_buff->channels);		goto error_free_cb_buff;	} 	indio_dev = cb_buff->channels[0].indio_dev;	cb_buff->buffer.scan_mask		= kcalloc(BITS_TO_LONGS(indio_dev->masklength), sizeof(long),			  GFP_KERNEL);	if (cb_buff->buffer.scan_mask == NULL) {		ret = -ENOMEM;		goto error_release_channels;	}	chan = &cb_buff->channels[0];	while (chan->indio_dev) {		if (chan->indio_dev != indio_dev) {			ret = -EINVAL;			goto error_free_scan_mask;		}		set_bit(chan->channel->scan_index,			cb_buff->buffer.scan_mask);		chan++;	} 	return cb_buff; error_free_scan_mask:	kfree(cb_buff->buffer.scan_mask);error_release_channels:	iio_channel_release_all(cb_buff->channels);error_free_cb_buff:	kfree(cb_buff);error_ret:	return ERR_PTR(ret);}EXPORT_SYMBOL_GPL(iio_channel_get_all_cb); int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff){	return iio_update_buffers(cb_buff->channels[0].indio_dev,				  &cb_buff->buffer,				  NULL);}EXPORT_SYMBOL_GPL(iio_channel_start_all_cb); void iio_channel_stop_all_cb(struct iio_cb_buffer *cb_buff){	iio_update_buffers(cb_buff->channels[0].indio_dev,			   NULL,			   &cb_buff->buffer);}EXPORT_SYMBOL_GPL(iio_channel_stop_all_cb); void iio_channel_release_all_cb(struct iio_cb_buffer *cb_buff){	iio_channel_release_all(cb_buff->channels);	iio_buffer_put(&cb_buff->buffer);}EXPORT_SYMBOL_GPL(iio_channel_release_all_cb); struct iio_channel*iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer){	return cb_buffer->channels;}EXPORT_SYMBOL_GPL(iio_channel_cb_get_channels);