1// SPDX-License-Identifier: GPL-2.0-only
2/* The industrial I/O callback buffer
3 */
4
5#include <linux/kernel.h>
6#include <linux/module.h>
7#include <linux/slab.h>
8#include <linux/err.h>
9#include <linux/export.h>
10#include <linux/iio/iio.h>
11#include <linux/iio/buffer_impl.h>
12#include <linux/iio/consumer.h>
13
14struct iio_cb_buffer {
15 struct iio_buffer buffer;
16 int (*cb)(const void *data, void *private);
17 void *private;
18 struct iio_channel *channels;
19 struct iio_dev *indio_dev;
20};
21
22static struct iio_cb_buffer *buffer_to_cb_buffer(struct iio_buffer *buffer)
23{
24 return container_of(buffer, struct iio_cb_buffer, buffer);
25}
26
27static int iio_buffer_cb_store_to(struct iio_buffer *buffer, const void *data)
28{
29 struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);
30 return cb_buff->cb(data, cb_buff->private);
31}
32
33static void iio_buffer_cb_release(struct iio_buffer *buffer)
34{
35 struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);
36
37 bitmap_free(bitmap: cb_buff->buffer.scan_mask);
38 kfree(objp: 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_channel *chan;
56
57 if (!cb) {
58 dev_err(dev, "Invalid arguments: A callback must be provided!\n");
59 return ERR_PTR(error: -EINVAL);
60 }
61
62 cb_buff = kzalloc(size: sizeof(*cb_buff), GFP_KERNEL);
63 if (cb_buff == NULL)
64 return ERR_PTR(error: -ENOMEM);
65
66 iio_buffer_init(buffer: &cb_buff->buffer);
67
68 cb_buff->private = private;
69 cb_buff->cb = cb;
70 cb_buff->buffer.access = &iio_cb_access;
71 INIT_LIST_HEAD(list: &cb_buff->buffer.demux_list);
72
73 cb_buff->channels = iio_channel_get_all(dev);
74 if (IS_ERR(ptr: cb_buff->channels)) {
75 ret = PTR_ERR(ptr: cb_buff->channels);
76 goto error_free_cb_buff;
77 }
78
79 cb_buff->indio_dev = cb_buff->channels[0].indio_dev;
80 cb_buff->buffer.scan_mask = bitmap_zalloc(nbits: cb_buff->indio_dev->masklength,
81 GFP_KERNEL);
82 if (cb_buff->buffer.scan_mask == NULL) {
83 ret = -ENOMEM;
84 goto error_release_channels;
85 }
86 chan = &cb_buff->channels[0];
87 while (chan->indio_dev) {
88 if (chan->indio_dev != cb_buff->indio_dev) {
89 ret = -EINVAL;
90 goto error_free_scan_mask;
91 }
92 set_bit(nr: chan->channel->scan_index,
93 addr: cb_buff->buffer.scan_mask);
94 chan++;
95 }
96
97 return cb_buff;
98
99error_free_scan_mask:
100 bitmap_free(bitmap: cb_buff->buffer.scan_mask);
101error_release_channels:
102 iio_channel_release_all(chan: cb_buff->channels);
103error_free_cb_buff:
104 kfree(objp: cb_buff);
105 return ERR_PTR(error: ret);
106}
107EXPORT_SYMBOL_GPL(iio_channel_get_all_cb);
108
109int iio_channel_cb_set_buffer_watermark(struct iio_cb_buffer *cb_buff,
110 size_t watermark)
111{
112 if (!watermark)
113 return -EINVAL;
114 cb_buff->buffer.watermark = watermark;
115
116 return 0;
117}
118EXPORT_SYMBOL_GPL(iio_channel_cb_set_buffer_watermark);
119
120int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff)
121{
122 return iio_update_buffers(indio_dev: cb_buff->indio_dev, insert_buffer: &cb_buff->buffer,
123 NULL);
124}
125EXPORT_SYMBOL_GPL(iio_channel_start_all_cb);
126
127void iio_channel_stop_all_cb(struct iio_cb_buffer *cb_buff)
128{
129 iio_update_buffers(indio_dev: cb_buff->indio_dev, NULL, remove_buffer: &cb_buff->buffer);
130}
131EXPORT_SYMBOL_GPL(iio_channel_stop_all_cb);
132
133void iio_channel_release_all_cb(struct iio_cb_buffer *cb_buff)
134{
135 iio_channel_release_all(chan: cb_buff->channels);
136 iio_buffer_put(buffer: &cb_buff->buffer);
137}
138EXPORT_SYMBOL_GPL(iio_channel_release_all_cb);
139
140struct iio_channel
141*iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer)
142{
143 return cb_buffer->channels;
144}
145EXPORT_SYMBOL_GPL(iio_channel_cb_get_channels);
146
147struct iio_dev
148*iio_channel_cb_get_iio_dev(const struct iio_cb_buffer *cb_buffer)
149{
150 return cb_buffer->indio_dev;
151}
152EXPORT_SYMBOL_GPL(iio_channel_cb_get_iio_dev);
153
154MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
155MODULE_DESCRIPTION("Industrial I/O callback buffer");
156MODULE_LICENSE("GPL");
157

source code of linux/drivers/iio/buffer/industrialio-buffer-cb.c