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 | |
14 | struct 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 | |
22 | static 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 | |
27 | static 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 | |
33 | static 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 | |
41 | static 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 | |
48 | struct 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 | |
99 | error_free_scan_mask: |
100 | bitmap_free(bitmap: cb_buff->buffer.scan_mask); |
101 | error_release_channels: |
102 | iio_channel_release_all(chan: cb_buff->channels); |
103 | error_free_cb_buff: |
104 | kfree(objp: cb_buff); |
105 | return ERR_PTR(error: ret); |
106 | } |
107 | EXPORT_SYMBOL_GPL(iio_channel_get_all_cb); |
108 | |
109 | int 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 | } |
118 | EXPORT_SYMBOL_GPL(iio_channel_cb_set_buffer_watermark); |
119 | |
120 | int 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 | } |
125 | EXPORT_SYMBOL_GPL(iio_channel_start_all_cb); |
126 | |
127 | void 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 | } |
131 | EXPORT_SYMBOL_GPL(iio_channel_stop_all_cb); |
132 | |
133 | void 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 | } |
138 | EXPORT_SYMBOL_GPL(iio_channel_release_all_cb); |
139 | |
140 | struct iio_channel |
141 | *iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer) |
142 | { |
143 | return cb_buffer->channels; |
144 | } |
145 | EXPORT_SYMBOL_GPL(iio_channel_cb_get_channels); |
146 | |
147 | struct iio_dev |
148 | *iio_channel_cb_get_iio_dev(const struct iio_cb_buffer *cb_buffer) |
149 | { |
150 | return cb_buffer->indio_dev; |
151 | } |
152 | EXPORT_SYMBOL_GPL(iio_channel_cb_get_iio_dev); |
153 | |
154 | MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>" ); |
155 | MODULE_DESCRIPTION("Industrial I/O callback buffer" ); |
156 | MODULE_LICENSE("GPL" ); |
157 | |