tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* The industrial I/O callback buffer
2 *
3 * This program is free software; you can redistribute it and/or modify it
4 * under the terms of the GNU General Public License version 2 as published by
5 * the Free Software Foundation.
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/err.h>
12#include <linux/export.h>
13#include <linux/iio/buffer.h>
14#include <linux/iio/consumer.h>
15
16struct iio_cb_buffer {
17 struct iio_buffer buffer;
18 int (*cb)(const void *data, void *private);
19 void *private;
20 struct iio_channel *channels;
21};
22
23static struct iio_cb_buffer *buffer_to_cb_buffer(struct iio_buffer *buffer)
24{
25 return container_of(buffer, struct iio_cb_buffer, buffer);
26}
27
28static int iio_buffer_cb_store_to(struct iio_buffer *buffer, const void *data)
29{
30 struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);
31 return cb_buff->cb(data, cb_buff->private);
32}
33
34static void iio_buffer_cb_release(struct iio_buffer *buffer)
35{
36 struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);
37 kfree(cb_buff->buffer.scan_mask);
38 kfree(cb_buff);
39}
40
41static const struct iio_buffer_access_funcs iio_cb_access = {
42 .store_to = &iio_buffer_cb_store_to,
43 .release = &iio_buffer_cb_release,
44
45 .modes = INDIO_BUFFER_SOFTWARE | INDIO_BUFFER_TRIGGERED,
46};
47
48struct iio_cb_buffer *iio_channel_get_all_cb(struct device *dev,
49 int (*cb)(const void *data,
50 void *private),
51 void *private)
52{
53 int ret;
54 struct iio_cb_buffer *cb_buff;
55 struct iio_dev *indio_dev;
56 struct iio_channel *chan;
57
58 cb_buff = kzalloc(sizeof(*cb_buff), GFP_KERNEL);
59 if (cb_buff == NULL)
60 return ERR_PTR(-ENOMEM);
61
62 iio_buffer_init(&cb_buff->buffer);
63
64 cb_buff->private = private;
65 cb_buff->cb = cb;
66 cb_buff->buffer.access = &iio_cb_access;
67 INIT_LIST_HEAD(&cb_buff->buffer.demux_list);
68
69 cb_buff->channels = iio_channel_get_all(dev);
70 if (IS_ERR(cb_buff->channels)) {
71 ret = PTR_ERR(cb_buff->channels);
72 goto error_free_cb_buff;
73 }
74
75 indio_dev = cb_buff->channels[0].indio_dev;
76 cb_buff->buffer.scan_mask
77 = kcalloc(BITS_TO_LONGS(indio_dev->masklength), sizeof(long),
78 GFP_KERNEL);
79 if (cb_buff->buffer.scan_mask == NULL) {
80 ret = -ENOMEM;
81 goto error_release_channels;
82 }
83 chan = &cb_buff->channels[0];
84 while (chan->indio_dev) {
85 if (chan->indio_dev != indio_dev) {
86 ret = -EINVAL;
87 goto error_free_scan_mask;
88 }
89 set_bit(chan->channel->scan_index,
90 cb_buff->buffer.scan_mask);
91 chan++;
92 }
93
94 return cb_buff;
95
96error_free_scan_mask:
97 kfree(cb_buff->buffer.scan_mask);
98error_release_channels:
99 iio_channel_release_all(cb_buff->channels);
100error_free_cb_buff:
101 kfree(cb_buff);
102 return ERR_PTR(ret);
103}
104EXPORT_SYMBOL_GPL(iio_channel_get_all_cb);
105
106int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff)
107{
108 return iio_update_buffers(cb_buff->channels[0].indio_dev,
109 &cb_buff->buffer,
110 NULL);
111}
112EXPORT_SYMBOL_GPL(iio_channel_start_all_cb);
113
114void iio_channel_stop_all_cb(struct iio_cb_buffer *cb_buff)
115{
116 iio_update_buffers(cb_buff->channels[0].indio_dev,
117 NULL,
118 &cb_buff->buffer);
119}
120EXPORT_SYMBOL_GPL(iio_channel_stop_all_cb);
121
122void iio_channel_release_all_cb(struct iio_cb_buffer *cb_buff)
123{
124 iio_channel_release_all(cb_buff->channels);
125 iio_buffer_put(&cb_buff->buffer);
126}
127EXPORT_SYMBOL_GPL(iio_channel_release_all_cb);
128
129struct iio_channel
130*iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer)
131{
132 return cb_buffer->channels;
133}
134EXPORT_SYMBOL_GPL(iio_channel_cb_get_channels);
135
136MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
137MODULE_DESCRIPTION("Industrial I/O callback buffer");
138MODULE_LICENSE("GPL");