Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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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/iio.h>
14#include <linux/iio/buffer_impl.h>
15#include <linux/iio/consumer.h>
16
17struct iio_cb_buffer {
18 struct iio_buffer buffer;
19 int (*cb)(const void *data, void *private);
20 void *private;
21 struct iio_channel *channels;
22 struct iio_dev *indio_dev;
23};
24
25static struct iio_cb_buffer *buffer_to_cb_buffer(struct iio_buffer *buffer)
26{
27 return container_of(buffer, struct iio_cb_buffer, buffer);
28}
29
30static int iio_buffer_cb_store_to(struct iio_buffer *buffer, const void *data)
31{
32 struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);
33 return cb_buff->cb(data, cb_buff->private);
34}
35
36static void iio_buffer_cb_release(struct iio_buffer *buffer)
37{
38 struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);
39
40 bitmap_free(cb_buff->buffer.scan_mask);
41 kfree(cb_buff);
42}
43
44static const struct iio_buffer_access_funcs iio_cb_access = {
45 .store_to = &iio_buffer_cb_store_to,
46 .release = &iio_buffer_cb_release,
47
48 .modes = INDIO_BUFFER_SOFTWARE | INDIO_BUFFER_TRIGGERED,
49};
50
51struct iio_cb_buffer *iio_channel_get_all_cb(struct device *dev,
52 int (*cb)(const void *data,
53 void *private),
54 void *private)
55{
56 int ret;
57 struct iio_cb_buffer *cb_buff;
58 struct iio_channel *chan;
59
60 cb_buff = kzalloc(sizeof(*cb_buff), GFP_KERNEL);
61 if (cb_buff == NULL)
62 return ERR_PTR(-ENOMEM);
63
64 iio_buffer_init(&cb_buff->buffer);
65
66 cb_buff->private = private;
67 cb_buff->cb = cb;
68 cb_buff->buffer.access = &iio_cb_access;
69 INIT_LIST_HEAD(&cb_buff->buffer.demux_list);
70
71 cb_buff->channels = iio_channel_get_all(dev);
72 if (IS_ERR(cb_buff->channels)) {
73 ret = PTR_ERR(cb_buff->channels);
74 goto error_free_cb_buff;
75 }
76
77 cb_buff->indio_dev = cb_buff->channels[0].indio_dev;
78 cb_buff->buffer.scan_mask = bitmap_zalloc(cb_buff->indio_dev->masklength,
79 GFP_KERNEL);
80 if (cb_buff->buffer.scan_mask == NULL) {
81 ret = -ENOMEM;
82 goto error_release_channels;
83 }
84 chan = &cb_buff->channels[0];
85 while (chan->indio_dev) {
86 if (chan->indio_dev != cb_buff->indio_dev) {
87 ret = -EINVAL;
88 goto error_free_scan_mask;
89 }
90 set_bit(chan->channel->scan_index,
91 cb_buff->buffer.scan_mask);
92 chan++;
93 }
94
95 return cb_buff;
96
97error_free_scan_mask:
98 bitmap_free(cb_buff->buffer.scan_mask);
99error_release_channels:
100 iio_channel_release_all(cb_buff->channels);
101error_free_cb_buff:
102 kfree(cb_buff);
103 return ERR_PTR(ret);
104}
105EXPORT_SYMBOL_GPL(iio_channel_get_all_cb);
106
107int iio_channel_cb_set_buffer_watermark(struct iio_cb_buffer *cb_buff,
108 size_t watermark)
109{
110 if (!watermark)
111 return -EINVAL;
112 cb_buff->buffer.watermark = watermark;
113
114 return 0;
115}
116EXPORT_SYMBOL_GPL(iio_channel_cb_set_buffer_watermark);
117
118int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff)
119{
120 return iio_update_buffers(cb_buff->indio_dev, &cb_buff->buffer,
121 NULL);
122}
123EXPORT_SYMBOL_GPL(iio_channel_start_all_cb);
124
125void iio_channel_stop_all_cb(struct iio_cb_buffer *cb_buff)
126{
127 iio_update_buffers(cb_buff->indio_dev, NULL, &cb_buff->buffer);
128}
129EXPORT_SYMBOL_GPL(iio_channel_stop_all_cb);
130
131void iio_channel_release_all_cb(struct iio_cb_buffer *cb_buff)
132{
133 iio_channel_release_all(cb_buff->channels);
134 iio_buffer_put(&cb_buff->buffer);
135}
136EXPORT_SYMBOL_GPL(iio_channel_release_all_cb);
137
138struct iio_channel
139*iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer)
140{
141 return cb_buffer->channels;
142}
143EXPORT_SYMBOL_GPL(iio_channel_cb_get_channels);
144
145struct iio_dev
146*iio_channel_cb_get_iio_dev(const struct iio_cb_buffer *cb_buffer)
147{
148 return cb_buffer->indio_dev;
149}
150EXPORT_SYMBOL_GPL(iio_channel_cb_get_iio_dev);
151
152MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
153MODULE_DESCRIPTION("Industrial I/O callback buffer");
154MODULE_LICENSE("GPL");