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// SPDX-License-Identifier: GPL-2.0-only
/* The industrial I/O callback buffer
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer_impl.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;
struct iio_dev *indio_dev;
};
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);
bitmap_free(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,
.modes = INDIO_BUFFER_SOFTWARE | INDIO_BUFFER_TRIGGERED,
};
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_channel *chan;
if (!cb) {
dev_err(dev, "Invalid arguments: A callback must be provided!\n");
return ERR_PTR(-EINVAL);
}
cb_buff = kzalloc(sizeof(*cb_buff), GFP_KERNEL);
if (cb_buff == NULL)
return ERR_PTR(-ENOMEM);
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;
}
cb_buff->indio_dev = cb_buff->channels[0].indio_dev;
cb_buff->buffer.scan_mask = bitmap_zalloc(iio_get_masklength(cb_buff->indio_dev),
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 != cb_buff->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:
bitmap_free(cb_buff->buffer.scan_mask);
error_release_channels:
iio_channel_release_all(cb_buff->channels);
error_free_cb_buff:
kfree(cb_buff);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(iio_channel_get_all_cb);
int iio_channel_cb_set_buffer_watermark(struct iio_cb_buffer *cb_buff,
size_t watermark)
{
if (!watermark)
return -EINVAL;
cb_buff->buffer.watermark = watermark;
return 0;
}
EXPORT_SYMBOL_GPL(iio_channel_cb_set_buffer_watermark);
int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff)
{
return iio_update_buffers(cb_buff->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->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);
struct iio_dev
*iio_channel_cb_get_iio_dev(const struct iio_cb_buffer *cb_buffer)
{
return cb_buffer->indio_dev;
}
EXPORT_SYMBOL_GPL(iio_channel_cb_get_iio_dev);
MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
MODULE_DESCRIPTION("Industrial I/O callback buffer");
MODULE_LICENSE("GPL");
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