summaryrefslogtreecommitdiffstats
path: root/drivers/iio/buffer/industrialio-buffer-cb.c
blob: ea63c838eeae523652f4270e1489d61ae385dd96 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
/* The industrial I/O callback buffer
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#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);
	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,

	.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;

	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
		= kcalloc(BITS_TO_LONGS(cb_buff->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 != 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:
	kfree(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");