Commit | Line | Data |
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7026ea4b JC |
1 | /* The industrial I/O core |
2 | * | |
3 | * Copyright (c) 2008 Jonathan Cameron | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify it | |
6 | * under the terms of the GNU General Public License version 2 as published by | |
7 | * the Free Software Foundation. | |
8 | * | |
14555b14 | 9 | * Handling of buffer allocation / resizing. |
7026ea4b JC |
10 | * |
11 | * | |
12 | * Things to look at here. | |
13 | * - Better memory allocation techniques? | |
14 | * - Alternative access techniques? | |
15 | */ | |
16 | #include <linux/kernel.h> | |
8e336a72 | 17 | #include <linux/export.h> |
7026ea4b | 18 | #include <linux/device.h> |
7026ea4b | 19 | #include <linux/fs.h> |
7026ea4b | 20 | #include <linux/cdev.h> |
5a0e3ad6 | 21 | #include <linux/slab.h> |
a7348347 | 22 | #include <linux/poll.h> |
d2f0a48f | 23 | #include <linux/sched.h> |
7026ea4b | 24 | |
06458e27 | 25 | #include <linux/iio/iio.h> |
df9c1c42 | 26 | #include "iio_core.h" |
06458e27 JC |
27 | #include <linux/iio/sysfs.h> |
28 | #include <linux/iio/buffer.h> | |
7026ea4b | 29 | |
8310b86c JC |
30 | static const char * const iio_endian_prefix[] = { |
31 | [IIO_BE] = "be", | |
32 | [IIO_LE] = "le", | |
33 | }; | |
7026ea4b | 34 | |
705ee2c9 | 35 | static bool iio_buffer_is_active(struct iio_buffer *buf) |
84b36ce5 | 36 | { |
705ee2c9 | 37 | return !list_empty(&buf->buffer_list); |
84b36ce5 JC |
38 | } |
39 | ||
647cc7b9 LPC |
40 | static bool iio_buffer_data_available(struct iio_buffer *buf) |
41 | { | |
9dd4694d | 42 | return buf->access->data_available(buf); |
647cc7b9 LPC |
43 | } |
44 | ||
7026ea4b | 45 | /** |
14555b14 | 46 | * iio_buffer_read_first_n_outer() - chrdev read for buffer access |
7026ea4b | 47 | * |
14555b14 JC |
48 | * This function relies on all buffer implementations having an |
49 | * iio_buffer as their first element. | |
7026ea4b | 50 | **/ |
14555b14 JC |
51 | ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf, |
52 | size_t n, loff_t *f_ps) | |
7026ea4b | 53 | { |
1aa04278 | 54 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 55 | struct iio_buffer *rb = indio_dev->buffer; |
ee551a10 | 56 | int ret; |
d5857d65 | 57 | |
f18e7a06 LPC |
58 | if (!indio_dev->info) |
59 | return -ENODEV; | |
60 | ||
96e00f11 | 61 | if (!rb || !rb->access->read_first_n) |
7026ea4b | 62 | return -EINVAL; |
ee551a10 LPC |
63 | |
64 | do { | |
65 | if (!iio_buffer_data_available(rb)) { | |
66 | if (filp->f_flags & O_NONBLOCK) | |
67 | return -EAGAIN; | |
68 | ||
69 | ret = wait_event_interruptible(rb->pollq, | |
70 | iio_buffer_data_available(rb) || | |
71 | indio_dev->info == NULL); | |
72 | if (ret) | |
73 | return ret; | |
74 | if (indio_dev->info == NULL) | |
75 | return -ENODEV; | |
76 | } | |
77 | ||
78 | ret = rb->access->read_first_n(rb, n, buf); | |
79 | if (ret == 0 && (filp->f_flags & O_NONBLOCK)) | |
80 | ret = -EAGAIN; | |
81 | } while (ret == 0); | |
82 | ||
83 | return ret; | |
7026ea4b JC |
84 | } |
85 | ||
a7348347 | 86 | /** |
14555b14 | 87 | * iio_buffer_poll() - poll the buffer to find out if it has data |
a7348347 | 88 | */ |
14555b14 JC |
89 | unsigned int iio_buffer_poll(struct file *filp, |
90 | struct poll_table_struct *wait) | |
a7348347 | 91 | { |
1aa04278 | 92 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 93 | struct iio_buffer *rb = indio_dev->buffer; |
a7348347 | 94 | |
f18e7a06 LPC |
95 | if (!indio_dev->info) |
96 | return -ENODEV; | |
97 | ||
a7348347 | 98 | poll_wait(filp, &rb->pollq, wait); |
647cc7b9 | 99 | if (iio_buffer_data_available(rb)) |
a7348347 JC |
100 | return POLLIN | POLLRDNORM; |
101 | /* need a way of knowing if there may be enough data... */ | |
8d213f24 | 102 | return 0; |
a7348347 JC |
103 | } |
104 | ||
d2f0a48f LPC |
105 | /** |
106 | * iio_buffer_wakeup_poll - Wakes up the buffer waitqueue | |
107 | * @indio_dev: The IIO device | |
108 | * | |
109 | * Wakes up the event waitqueue used for poll(). Should usually | |
110 | * be called when the device is unregistered. | |
111 | */ | |
112 | void iio_buffer_wakeup_poll(struct iio_dev *indio_dev) | |
113 | { | |
114 | if (!indio_dev->buffer) | |
115 | return; | |
116 | ||
117 | wake_up(&indio_dev->buffer->pollq); | |
118 | } | |
119 | ||
f79a9098 | 120 | void iio_buffer_init(struct iio_buffer *buffer) |
7026ea4b | 121 | { |
5ada4ea9 | 122 | INIT_LIST_HEAD(&buffer->demux_list); |
705ee2c9 | 123 | INIT_LIST_HEAD(&buffer->buffer_list); |
14555b14 | 124 | init_waitqueue_head(&buffer->pollq); |
9e69c935 | 125 | kref_init(&buffer->ref); |
7026ea4b | 126 | } |
14555b14 | 127 | EXPORT_SYMBOL(iio_buffer_init); |
7026ea4b | 128 | |
1d892719 | 129 | static ssize_t iio_show_scan_index(struct device *dev, |
8d213f24 JC |
130 | struct device_attribute *attr, |
131 | char *buf) | |
1d892719 | 132 | { |
8d213f24 | 133 | return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index); |
1d892719 JC |
134 | } |
135 | ||
136 | static ssize_t iio_show_fixed_type(struct device *dev, | |
137 | struct device_attribute *attr, | |
138 | char *buf) | |
139 | { | |
140 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); | |
8310b86c JC |
141 | u8 type = this_attr->c->scan_type.endianness; |
142 | ||
143 | if (type == IIO_CPU) { | |
9d5d1153 JC |
144 | #ifdef __LITTLE_ENDIAN |
145 | type = IIO_LE; | |
146 | #else | |
147 | type = IIO_BE; | |
148 | #endif | |
8310b86c | 149 | } |
0ee8546a SP |
150 | if (this_attr->c->scan_type.repeat > 1) |
151 | return sprintf(buf, "%s:%c%d/%dX%d>>%u\n", | |
152 | iio_endian_prefix[type], | |
153 | this_attr->c->scan_type.sign, | |
154 | this_attr->c->scan_type.realbits, | |
155 | this_attr->c->scan_type.storagebits, | |
156 | this_attr->c->scan_type.repeat, | |
157 | this_attr->c->scan_type.shift); | |
158 | else | |
159 | return sprintf(buf, "%s:%c%d/%d>>%u\n", | |
8310b86c | 160 | iio_endian_prefix[type], |
1d892719 JC |
161 | this_attr->c->scan_type.sign, |
162 | this_attr->c->scan_type.realbits, | |
163 | this_attr->c->scan_type.storagebits, | |
164 | this_attr->c->scan_type.shift); | |
165 | } | |
166 | ||
8d213f24 JC |
167 | static ssize_t iio_scan_el_show(struct device *dev, |
168 | struct device_attribute *attr, | |
169 | char *buf) | |
170 | { | |
171 | int ret; | |
e53f5ac5 | 172 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 173 | |
2076a20f AB |
174 | /* Ensure ret is 0 or 1. */ |
175 | ret = !!test_bit(to_iio_dev_attr(attr)->address, | |
5ada4ea9 JC |
176 | indio_dev->buffer->scan_mask); |
177 | ||
8d213f24 JC |
178 | return sprintf(buf, "%d\n", ret); |
179 | } | |
180 | ||
217a5cf0 LPC |
181 | /* Note NULL used as error indicator as it doesn't make sense. */ |
182 | static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks, | |
183 | unsigned int masklength, | |
184 | const unsigned long *mask) | |
185 | { | |
186 | if (bitmap_empty(mask, masklength)) | |
187 | return NULL; | |
188 | while (*av_masks) { | |
189 | if (bitmap_subset(mask, av_masks, masklength)) | |
190 | return av_masks; | |
191 | av_masks += BITS_TO_LONGS(masklength); | |
192 | } | |
193 | return NULL; | |
194 | } | |
195 | ||
196 | static bool iio_validate_scan_mask(struct iio_dev *indio_dev, | |
197 | const unsigned long *mask) | |
198 | { | |
199 | if (!indio_dev->setup_ops->validate_scan_mask) | |
200 | return true; | |
201 | ||
202 | return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask); | |
203 | } | |
204 | ||
205 | /** | |
206 | * iio_scan_mask_set() - set particular bit in the scan mask | |
207 | * @indio_dev: the iio device | |
208 | * @buffer: the buffer whose scan mask we are interested in | |
209 | * @bit: the bit to be set. | |
210 | * | |
211 | * Note that at this point we have no way of knowing what other | |
212 | * buffers might request, hence this code only verifies that the | |
213 | * individual buffers request is plausible. | |
214 | */ | |
215 | static int iio_scan_mask_set(struct iio_dev *indio_dev, | |
216 | struct iio_buffer *buffer, int bit) | |
217 | { | |
218 | const unsigned long *mask; | |
219 | unsigned long *trialmask; | |
220 | ||
221 | trialmask = kmalloc(sizeof(*trialmask)* | |
222 | BITS_TO_LONGS(indio_dev->masklength), | |
223 | GFP_KERNEL); | |
224 | ||
225 | if (trialmask == NULL) | |
226 | return -ENOMEM; | |
227 | if (!indio_dev->masklength) { | |
228 | WARN_ON("Trying to set scanmask prior to registering buffer\n"); | |
229 | goto err_invalid_mask; | |
230 | } | |
231 | bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength); | |
232 | set_bit(bit, trialmask); | |
233 | ||
234 | if (!iio_validate_scan_mask(indio_dev, trialmask)) | |
235 | goto err_invalid_mask; | |
236 | ||
237 | if (indio_dev->available_scan_masks) { | |
238 | mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
239 | indio_dev->masklength, | |
240 | trialmask); | |
241 | if (!mask) | |
242 | goto err_invalid_mask; | |
243 | } | |
244 | bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength); | |
245 | ||
246 | kfree(trialmask); | |
247 | ||
248 | return 0; | |
249 | ||
250 | err_invalid_mask: | |
251 | kfree(trialmask); | |
252 | return -EINVAL; | |
253 | } | |
254 | ||
14555b14 | 255 | static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit) |
8d213f24 | 256 | { |
14555b14 | 257 | clear_bit(bit, buffer->scan_mask); |
8d213f24 JC |
258 | return 0; |
259 | } | |
260 | ||
261 | static ssize_t iio_scan_el_store(struct device *dev, | |
262 | struct device_attribute *attr, | |
263 | const char *buf, | |
264 | size_t len) | |
265 | { | |
a714af27 | 266 | int ret; |
8d213f24 | 267 | bool state; |
e53f5ac5 | 268 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 269 | struct iio_buffer *buffer = indio_dev->buffer; |
8d213f24 JC |
270 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
271 | ||
a714af27 JC |
272 | ret = strtobool(buf, &state); |
273 | if (ret < 0) | |
274 | return ret; | |
8d213f24 | 275 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 276 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
277 | ret = -EBUSY; |
278 | goto error_ret; | |
279 | } | |
f79a9098 | 280 | ret = iio_scan_mask_query(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
281 | if (ret < 0) |
282 | goto error_ret; | |
283 | if (!state && ret) { | |
14555b14 | 284 | ret = iio_scan_mask_clear(buffer, this_attr->address); |
8d213f24 JC |
285 | if (ret) |
286 | goto error_ret; | |
287 | } else if (state && !ret) { | |
f79a9098 | 288 | ret = iio_scan_mask_set(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
289 | if (ret) |
290 | goto error_ret; | |
291 | } | |
292 | ||
293 | error_ret: | |
294 | mutex_unlock(&indio_dev->mlock); | |
295 | ||
5a2a6e11 | 296 | return ret < 0 ? ret : len; |
8d213f24 JC |
297 | |
298 | } | |
299 | ||
300 | static ssize_t iio_scan_el_ts_show(struct device *dev, | |
301 | struct device_attribute *attr, | |
302 | char *buf) | |
303 | { | |
e53f5ac5 | 304 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
f8c6f4e9 | 305 | return sprintf(buf, "%d\n", indio_dev->buffer->scan_timestamp); |
8d213f24 JC |
306 | } |
307 | ||
308 | static ssize_t iio_scan_el_ts_store(struct device *dev, | |
309 | struct device_attribute *attr, | |
310 | const char *buf, | |
311 | size_t len) | |
312 | { | |
a714af27 | 313 | int ret; |
e53f5ac5 | 314 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 315 | bool state; |
1aa04278 | 316 | |
a714af27 JC |
317 | ret = strtobool(buf, &state); |
318 | if (ret < 0) | |
319 | return ret; | |
320 | ||
8d213f24 | 321 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 322 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
323 | ret = -EBUSY; |
324 | goto error_ret; | |
325 | } | |
14555b14 | 326 | indio_dev->buffer->scan_timestamp = state; |
8d213f24 JC |
327 | error_ret: |
328 | mutex_unlock(&indio_dev->mlock); | |
329 | ||
330 | return ret ? ret : len; | |
331 | } | |
332 | ||
14555b14 JC |
333 | static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev, |
334 | const struct iio_chan_spec *chan) | |
1d892719 | 335 | { |
26d25ae3 | 336 | int ret, attrcount = 0; |
14555b14 | 337 | struct iio_buffer *buffer = indio_dev->buffer; |
1d892719 | 338 | |
26d25ae3 | 339 | ret = __iio_add_chan_devattr("index", |
1d892719 JC |
340 | chan, |
341 | &iio_show_scan_index, | |
342 | NULL, | |
343 | 0, | |
3704432f | 344 | IIO_SEPARATE, |
1aa04278 | 345 | &indio_dev->dev, |
14555b14 | 346 | &buffer->scan_el_dev_attr_list); |
1d892719 | 347 | if (ret) |
92825ff9 | 348 | return ret; |
26d25ae3 JC |
349 | attrcount++; |
350 | ret = __iio_add_chan_devattr("type", | |
1d892719 JC |
351 | chan, |
352 | &iio_show_fixed_type, | |
353 | NULL, | |
354 | 0, | |
355 | 0, | |
1aa04278 | 356 | &indio_dev->dev, |
14555b14 | 357 | &buffer->scan_el_dev_attr_list); |
1d892719 | 358 | if (ret) |
92825ff9 | 359 | return ret; |
26d25ae3 | 360 | attrcount++; |
a88b3ebc | 361 | if (chan->type != IIO_TIMESTAMP) |
26d25ae3 | 362 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
363 | chan, |
364 | &iio_scan_el_show, | |
365 | &iio_scan_el_store, | |
366 | chan->scan_index, | |
367 | 0, | |
1aa04278 | 368 | &indio_dev->dev, |
14555b14 | 369 | &buffer->scan_el_dev_attr_list); |
a88b3ebc | 370 | else |
26d25ae3 | 371 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
372 | chan, |
373 | &iio_scan_el_ts_show, | |
374 | &iio_scan_el_ts_store, | |
375 | chan->scan_index, | |
376 | 0, | |
1aa04278 | 377 | &indio_dev->dev, |
14555b14 | 378 | &buffer->scan_el_dev_attr_list); |
9572588c | 379 | if (ret) |
92825ff9 | 380 | return ret; |
26d25ae3 JC |
381 | attrcount++; |
382 | ret = attrcount; | |
1d892719 JC |
383 | return ret; |
384 | } | |
385 | ||
26d25ae3 JC |
386 | static const char * const iio_scan_elements_group_name = "scan_elements"; |
387 | ||
14555b14 JC |
388 | int iio_buffer_register(struct iio_dev *indio_dev, |
389 | const struct iio_chan_spec *channels, | |
390 | int num_channels) | |
1d892719 | 391 | { |
26d25ae3 JC |
392 | struct iio_dev_attr *p; |
393 | struct attribute **attr; | |
14555b14 | 394 | struct iio_buffer *buffer = indio_dev->buffer; |
26d25ae3 JC |
395 | int ret, i, attrn, attrcount, attrcount_orig = 0; |
396 | ||
14555b14 JC |
397 | if (buffer->attrs) |
398 | indio_dev->groups[indio_dev->groupcounter++] = buffer->attrs; | |
bf32963c | 399 | |
14555b14 JC |
400 | if (buffer->scan_el_attrs != NULL) { |
401 | attr = buffer->scan_el_attrs->attrs; | |
26d25ae3 JC |
402 | while (*attr++ != NULL) |
403 | attrcount_orig++; | |
404 | } | |
405 | attrcount = attrcount_orig; | |
14555b14 | 406 | INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); |
1d892719 JC |
407 | if (channels) { |
408 | /* new magic */ | |
409 | for (i = 0; i < num_channels; i++) { | |
f5b81ddd LPC |
410 | if (channels[i].scan_index < 0) |
411 | continue; | |
412 | ||
32b5eeca JC |
413 | /* Establish necessary mask length */ |
414 | if (channels[i].scan_index > | |
415 | (int)indio_dev->masklength - 1) | |
416 | indio_dev->masklength | |
e1dc7bee | 417 | = channels[i].scan_index + 1; |
32b5eeca | 418 | |
14555b14 | 419 | ret = iio_buffer_add_channel_sysfs(indio_dev, |
1aa04278 | 420 | &channels[i]); |
1d892719 | 421 | if (ret < 0) |
26d25ae3 JC |
422 | goto error_cleanup_dynamic; |
423 | attrcount += ret; | |
beb80600 | 424 | if (channels[i].type == IIO_TIMESTAMP) |
f1264809 | 425 | indio_dev->scan_index_timestamp = |
beb80600 | 426 | channels[i].scan_index; |
1d892719 | 427 | } |
14555b14 | 428 | if (indio_dev->masklength && buffer->scan_mask == NULL) { |
d83fb184 TM |
429 | buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), |
430 | sizeof(*buffer->scan_mask), | |
431 | GFP_KERNEL); | |
14555b14 | 432 | if (buffer->scan_mask == NULL) { |
32b5eeca | 433 | ret = -ENOMEM; |
26d25ae3 | 434 | goto error_cleanup_dynamic; |
32b5eeca JC |
435 | } |
436 | } | |
1d892719 JC |
437 | } |
438 | ||
14555b14 | 439 | buffer->scan_el_group.name = iio_scan_elements_group_name; |
26d25ae3 | 440 | |
d83fb184 TM |
441 | buffer->scan_el_group.attrs = kcalloc(attrcount + 1, |
442 | sizeof(buffer->scan_el_group.attrs[0]), | |
443 | GFP_KERNEL); | |
14555b14 | 444 | if (buffer->scan_el_group.attrs == NULL) { |
26d25ae3 JC |
445 | ret = -ENOMEM; |
446 | goto error_free_scan_mask; | |
447 | } | |
14555b14 JC |
448 | if (buffer->scan_el_attrs) |
449 | memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs, | |
450 | sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig); | |
26d25ae3 JC |
451 | attrn = attrcount_orig; |
452 | ||
14555b14 JC |
453 | list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l) |
454 | buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr; | |
455 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group; | |
26d25ae3 | 456 | |
1d892719 | 457 | return 0; |
26d25ae3 JC |
458 | |
459 | error_free_scan_mask: | |
14555b14 | 460 | kfree(buffer->scan_mask); |
1d892719 | 461 | error_cleanup_dynamic: |
84088ebd | 462 | iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); |
26d25ae3 | 463 | |
7026ea4b JC |
464 | return ret; |
465 | } | |
14555b14 | 466 | EXPORT_SYMBOL(iio_buffer_register); |
1d892719 | 467 | |
14555b14 | 468 | void iio_buffer_unregister(struct iio_dev *indio_dev) |
7026ea4b | 469 | { |
14555b14 JC |
470 | kfree(indio_dev->buffer->scan_mask); |
471 | kfree(indio_dev->buffer->scan_el_group.attrs); | |
84088ebd | 472 | iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list); |
7026ea4b | 473 | } |
14555b14 | 474 | EXPORT_SYMBOL(iio_buffer_unregister); |
7026ea4b | 475 | |
14555b14 JC |
476 | ssize_t iio_buffer_read_length(struct device *dev, |
477 | struct device_attribute *attr, | |
478 | char *buf) | |
7026ea4b | 479 | { |
e53f5ac5 | 480 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 481 | struct iio_buffer *buffer = indio_dev->buffer; |
7026ea4b | 482 | |
14555b14 | 483 | if (buffer->access->get_length) |
8d213f24 | 484 | return sprintf(buf, "%d\n", |
14555b14 | 485 | buffer->access->get_length(buffer)); |
7026ea4b | 486 | |
8d213f24 | 487 | return 0; |
7026ea4b | 488 | } |
14555b14 | 489 | EXPORT_SYMBOL(iio_buffer_read_length); |
7026ea4b | 490 | |
14555b14 JC |
491 | ssize_t iio_buffer_write_length(struct device *dev, |
492 | struct device_attribute *attr, | |
493 | const char *buf, | |
494 | size_t len) | |
7026ea4b | 495 | { |
e53f5ac5 | 496 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 497 | struct iio_buffer *buffer = indio_dev->buffer; |
948ad205 LPC |
498 | unsigned int val; |
499 | int ret; | |
8d213f24 | 500 | |
948ad205 | 501 | ret = kstrtouint(buf, 10, &val); |
7026ea4b JC |
502 | if (ret) |
503 | return ret; | |
504 | ||
14555b14 JC |
505 | if (buffer->access->get_length) |
506 | if (val == buffer->access->get_length(buffer)) | |
7026ea4b JC |
507 | return len; |
508 | ||
e38c79e0 | 509 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 510 | if (iio_buffer_is_active(indio_dev->buffer)) { |
e38c79e0 LPC |
511 | ret = -EBUSY; |
512 | } else { | |
869871b5 | 513 | if (buffer->access->set_length) |
e38c79e0 | 514 | buffer->access->set_length(buffer, val); |
e38c79e0 | 515 | ret = 0; |
7026ea4b | 516 | } |
e38c79e0 | 517 | mutex_unlock(&indio_dev->mlock); |
7026ea4b | 518 | |
e38c79e0 | 519 | return ret ? ret : len; |
7026ea4b | 520 | } |
14555b14 | 521 | EXPORT_SYMBOL(iio_buffer_write_length); |
7026ea4b | 522 | |
14555b14 JC |
523 | ssize_t iio_buffer_show_enable(struct device *dev, |
524 | struct device_attribute *attr, | |
525 | char *buf) | |
7026ea4b | 526 | { |
e53f5ac5 | 527 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
705ee2c9 | 528 | return sprintf(buf, "%d\n", iio_buffer_is_active(indio_dev->buffer)); |
7026ea4b | 529 | } |
14555b14 | 530 | EXPORT_SYMBOL(iio_buffer_show_enable); |
7026ea4b | 531 | |
183f4173 PM |
532 | static int iio_compute_scan_bytes(struct iio_dev *indio_dev, |
533 | const unsigned long *mask, bool timestamp) | |
959d2952 | 534 | { |
959d2952 JC |
535 | const struct iio_chan_spec *ch; |
536 | unsigned bytes = 0; | |
537 | int length, i; | |
959d2952 JC |
538 | |
539 | /* How much space will the demuxed element take? */ | |
6b3b58ed | 540 | for_each_set_bit(i, mask, |
959d2952 JC |
541 | indio_dev->masklength) { |
542 | ch = iio_find_channel_from_si(indio_dev, i); | |
0ee8546a SP |
543 | if (ch->scan_type.repeat > 1) |
544 | length = ch->scan_type.storagebits / 8 * | |
545 | ch->scan_type.repeat; | |
546 | else | |
547 | length = ch->scan_type.storagebits / 8; | |
959d2952 JC |
548 | bytes = ALIGN(bytes, length); |
549 | bytes += length; | |
550 | } | |
6b3b58ed | 551 | if (timestamp) { |
959d2952 | 552 | ch = iio_find_channel_from_si(indio_dev, |
f1264809 | 553 | indio_dev->scan_index_timestamp); |
0ee8546a SP |
554 | if (ch->scan_type.repeat > 1) |
555 | length = ch->scan_type.storagebits / 8 * | |
556 | ch->scan_type.repeat; | |
557 | else | |
558 | length = ch->scan_type.storagebits / 8; | |
959d2952 JC |
559 | bytes = ALIGN(bytes, length); |
560 | bytes += length; | |
561 | } | |
6b3b58ed JC |
562 | return bytes; |
563 | } | |
564 | ||
9e69c935 LPC |
565 | static void iio_buffer_activate(struct iio_dev *indio_dev, |
566 | struct iio_buffer *buffer) | |
567 | { | |
568 | iio_buffer_get(buffer); | |
569 | list_add(&buffer->buffer_list, &indio_dev->buffer_list); | |
570 | } | |
571 | ||
572 | static void iio_buffer_deactivate(struct iio_buffer *buffer) | |
573 | { | |
574 | list_del_init(&buffer->buffer_list); | |
575 | iio_buffer_put(buffer); | |
576 | } | |
577 | ||
a87c82e4 LPC |
578 | void iio_disable_all_buffers(struct iio_dev *indio_dev) |
579 | { | |
580 | struct iio_buffer *buffer, *_buffer; | |
581 | ||
582 | if (list_empty(&indio_dev->buffer_list)) | |
583 | return; | |
584 | ||
585 | if (indio_dev->setup_ops->predisable) | |
586 | indio_dev->setup_ops->predisable(indio_dev); | |
587 | ||
588 | list_for_each_entry_safe(buffer, _buffer, | |
589 | &indio_dev->buffer_list, buffer_list) | |
9e69c935 | 590 | iio_buffer_deactivate(buffer); |
a87c82e4 LPC |
591 | |
592 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
593 | if (indio_dev->setup_ops->postdisable) | |
594 | indio_dev->setup_ops->postdisable(indio_dev); | |
e086ed76 LPC |
595 | |
596 | if (indio_dev->available_scan_masks == NULL) | |
597 | kfree(indio_dev->active_scan_mask); | |
a87c82e4 LPC |
598 | } |
599 | ||
8e050996 LPC |
600 | static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev, |
601 | struct iio_buffer *buffer) | |
602 | { | |
603 | unsigned int bytes; | |
604 | ||
605 | if (!buffer->access->set_bytes_per_datum) | |
606 | return; | |
607 | ||
608 | bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask, | |
609 | buffer->scan_timestamp); | |
610 | ||
611 | buffer->access->set_bytes_per_datum(buffer, bytes); | |
612 | } | |
613 | ||
a9519456 | 614 | static int __iio_update_buffers(struct iio_dev *indio_dev, |
84b36ce5 JC |
615 | struct iio_buffer *insert_buffer, |
616 | struct iio_buffer *remove_buffer) | |
6b3b58ed | 617 | { |
84b36ce5 JC |
618 | int ret; |
619 | int success = 0; | |
620 | struct iio_buffer *buffer; | |
621 | unsigned long *compound_mask; | |
622 | const unsigned long *old_mask; | |
6b3b58ed | 623 | |
84b36ce5 JC |
624 | /* Wind down existing buffers - iff there are any */ |
625 | if (!list_empty(&indio_dev->buffer_list)) { | |
626 | if (indio_dev->setup_ops->predisable) { | |
627 | ret = indio_dev->setup_ops->predisable(indio_dev); | |
628 | if (ret) | |
92825ff9 | 629 | return ret; |
84b36ce5 JC |
630 | } |
631 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
632 | if (indio_dev->setup_ops->postdisable) { | |
633 | ret = indio_dev->setup_ops->postdisable(indio_dev); | |
634 | if (ret) | |
92825ff9 | 635 | return ret; |
84b36ce5 JC |
636 | } |
637 | } | |
638 | /* Keep a copy of current setup to allow roll back */ | |
639 | old_mask = indio_dev->active_scan_mask; | |
640 | if (!indio_dev->available_scan_masks) | |
641 | indio_dev->active_scan_mask = NULL; | |
642 | ||
643 | if (remove_buffer) | |
9e69c935 | 644 | iio_buffer_deactivate(remove_buffer); |
84b36ce5 | 645 | if (insert_buffer) |
9e69c935 | 646 | iio_buffer_activate(indio_dev, insert_buffer); |
84b36ce5 JC |
647 | |
648 | /* If no buffers in list, we are done */ | |
649 | if (list_empty(&indio_dev->buffer_list)) { | |
650 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
651 | if (indio_dev->available_scan_masks == NULL) | |
652 | kfree(old_mask); | |
653 | return 0; | |
654 | } | |
959d2952 | 655 | |
9572588c | 656 | /* What scan mask do we actually have? */ |
84b36ce5 JC |
657 | compound_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), |
658 | sizeof(long), GFP_KERNEL); | |
659 | if (compound_mask == NULL) { | |
660 | if (indio_dev->available_scan_masks == NULL) | |
661 | kfree(old_mask); | |
662 | return -ENOMEM; | |
663 | } | |
664 | indio_dev->scan_timestamp = 0; | |
665 | ||
666 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
667 | bitmap_or(compound_mask, compound_mask, buffer->scan_mask, | |
668 | indio_dev->masklength); | |
669 | indio_dev->scan_timestamp |= buffer->scan_timestamp; | |
670 | } | |
671 | if (indio_dev->available_scan_masks) { | |
959d2952 JC |
672 | indio_dev->active_scan_mask = |
673 | iio_scan_mask_match(indio_dev->available_scan_masks, | |
674 | indio_dev->masklength, | |
84b36ce5 JC |
675 | compound_mask); |
676 | if (indio_dev->active_scan_mask == NULL) { | |
677 | /* | |
678 | * Roll back. | |
679 | * Note can only occur when adding a buffer. | |
680 | */ | |
9e69c935 | 681 | iio_buffer_deactivate(insert_buffer); |
d66e0452 PM |
682 | if (old_mask) { |
683 | indio_dev->active_scan_mask = old_mask; | |
684 | success = -EINVAL; | |
685 | } | |
686 | else { | |
687 | kfree(compound_mask); | |
688 | ret = -EINVAL; | |
92825ff9 | 689 | return ret; |
d66e0452 | 690 | } |
84b36ce5 JC |
691 | } |
692 | } else { | |
693 | indio_dev->active_scan_mask = compound_mask; | |
694 | } | |
aff1eb4e | 695 | |
5ada4ea9 JC |
696 | iio_update_demux(indio_dev); |
697 | ||
84b36ce5 JC |
698 | /* Wind up again */ |
699 | if (indio_dev->setup_ops->preenable) { | |
700 | ret = indio_dev->setup_ops->preenable(indio_dev); | |
701 | if (ret) { | |
702 | printk(KERN_ERR | |
bec1889d | 703 | "Buffer not started: buffer preenable failed (%d)\n", ret); |
84b36ce5 JC |
704 | goto error_remove_inserted; |
705 | } | |
706 | } | |
707 | indio_dev->scan_bytes = | |
708 | iio_compute_scan_bytes(indio_dev, | |
709 | indio_dev->active_scan_mask, | |
710 | indio_dev->scan_timestamp); | |
8e050996 LPC |
711 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { |
712 | iio_buffer_update_bytes_per_datum(indio_dev, buffer); | |
84b36ce5 JC |
713 | if (buffer->access->request_update) { |
714 | ret = buffer->access->request_update(buffer); | |
715 | if (ret) { | |
716 | printk(KERN_INFO | |
bec1889d | 717 | "Buffer not started: buffer parameter update failed (%d)\n", ret); |
84b36ce5 JC |
718 | goto error_run_postdisable; |
719 | } | |
720 | } | |
8e050996 | 721 | } |
84b36ce5 JC |
722 | if (indio_dev->info->update_scan_mode) { |
723 | ret = indio_dev->info | |
5ada4ea9 JC |
724 | ->update_scan_mode(indio_dev, |
725 | indio_dev->active_scan_mask); | |
84b36ce5 | 726 | if (ret < 0) { |
bec1889d | 727 | printk(KERN_INFO "Buffer not started: update scan mode failed (%d)\n", ret); |
84b36ce5 JC |
728 | goto error_run_postdisable; |
729 | } | |
730 | } | |
9572588c | 731 | /* Definitely possible for devices to support both of these. */ |
84b36ce5 JC |
732 | if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) { |
733 | if (!indio_dev->trig) { | |
734 | printk(KERN_INFO "Buffer not started: no trigger\n"); | |
735 | ret = -EINVAL; | |
736 | /* Can only occur on first buffer */ | |
737 | goto error_run_postdisable; | |
738 | } | |
739 | indio_dev->currentmode = INDIO_BUFFER_TRIGGERED; | |
740 | } else if (indio_dev->modes & INDIO_BUFFER_HARDWARE) { | |
741 | indio_dev->currentmode = INDIO_BUFFER_HARDWARE; | |
9572588c | 742 | } else { /* Should never be reached */ |
84b36ce5 JC |
743 | ret = -EINVAL; |
744 | goto error_run_postdisable; | |
745 | } | |
746 | ||
747 | if (indio_dev->setup_ops->postenable) { | |
748 | ret = indio_dev->setup_ops->postenable(indio_dev); | |
749 | if (ret) { | |
750 | printk(KERN_INFO | |
bec1889d | 751 | "Buffer not started: postenable failed (%d)\n", ret); |
84b36ce5 JC |
752 | indio_dev->currentmode = INDIO_DIRECT_MODE; |
753 | if (indio_dev->setup_ops->postdisable) | |
754 | indio_dev->setup_ops->postdisable(indio_dev); | |
755 | goto error_disable_all_buffers; | |
756 | } | |
757 | } | |
758 | ||
759 | if (indio_dev->available_scan_masks) | |
760 | kfree(compound_mask); | |
761 | else | |
762 | kfree(old_mask); | |
763 | ||
764 | return success; | |
765 | ||
766 | error_disable_all_buffers: | |
767 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
768 | error_run_postdisable: | |
769 | if (indio_dev->setup_ops->postdisable) | |
770 | indio_dev->setup_ops->postdisable(indio_dev); | |
771 | error_remove_inserted: | |
84b36ce5 | 772 | if (insert_buffer) |
9e69c935 | 773 | iio_buffer_deactivate(insert_buffer); |
84b36ce5 JC |
774 | indio_dev->active_scan_mask = old_mask; |
775 | kfree(compound_mask); | |
84b36ce5 JC |
776 | return ret; |
777 | } | |
a9519456 LPC |
778 | |
779 | int iio_update_buffers(struct iio_dev *indio_dev, | |
780 | struct iio_buffer *insert_buffer, | |
781 | struct iio_buffer *remove_buffer) | |
782 | { | |
783 | int ret; | |
784 | ||
3909fab5 LPC |
785 | if (insert_buffer == remove_buffer) |
786 | return 0; | |
787 | ||
a9519456 LPC |
788 | mutex_lock(&indio_dev->info_exist_lock); |
789 | mutex_lock(&indio_dev->mlock); | |
790 | ||
3909fab5 LPC |
791 | if (insert_buffer && iio_buffer_is_active(insert_buffer)) |
792 | insert_buffer = NULL; | |
793 | ||
794 | if (remove_buffer && !iio_buffer_is_active(remove_buffer)) | |
795 | remove_buffer = NULL; | |
796 | ||
797 | if (!insert_buffer && !remove_buffer) { | |
798 | ret = 0; | |
799 | goto out_unlock; | |
800 | } | |
801 | ||
a9519456 LPC |
802 | if (indio_dev->info == NULL) { |
803 | ret = -ENODEV; | |
804 | goto out_unlock; | |
805 | } | |
806 | ||
807 | ret = __iio_update_buffers(indio_dev, insert_buffer, remove_buffer); | |
808 | ||
809 | out_unlock: | |
810 | mutex_unlock(&indio_dev->mlock); | |
811 | mutex_unlock(&indio_dev->info_exist_lock); | |
812 | ||
813 | return ret; | |
814 | } | |
84b36ce5 JC |
815 | EXPORT_SYMBOL_GPL(iio_update_buffers); |
816 | ||
817 | ssize_t iio_buffer_store_enable(struct device *dev, | |
818 | struct device_attribute *attr, | |
819 | const char *buf, | |
820 | size_t len) | |
821 | { | |
822 | int ret; | |
823 | bool requested_state; | |
824 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
84b36ce5 JC |
825 | bool inlist; |
826 | ||
827 | ret = strtobool(buf, &requested_state); | |
828 | if (ret < 0) | |
829 | return ret; | |
830 | ||
831 | mutex_lock(&indio_dev->mlock); | |
832 | ||
833 | /* Find out if it is in the list */ | |
705ee2c9 | 834 | inlist = iio_buffer_is_active(indio_dev->buffer); |
84b36ce5 JC |
835 | /* Already in desired state */ |
836 | if (inlist == requested_state) | |
837 | goto done; | |
838 | ||
839 | if (requested_state) | |
a9519456 | 840 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
841 | indio_dev->buffer, NULL); |
842 | else | |
a9519456 | 843 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
844 | NULL, indio_dev->buffer); |
845 | ||
846 | if (ret < 0) | |
847 | goto done; | |
848 | done: | |
849 | mutex_unlock(&indio_dev->mlock); | |
850 | return (ret < 0) ? ret : len; | |
851 | } | |
852 | EXPORT_SYMBOL(iio_buffer_store_enable); | |
853 | ||
81636632 LPC |
854 | /** |
855 | * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected | |
856 | * @indio_dev: the iio device | |
857 | * @mask: scan mask to be checked | |
858 | * | |
859 | * Return true if exactly one bit is set in the scan mask, false otherwise. It | |
860 | * can be used for devices where only one channel can be active for sampling at | |
861 | * a time. | |
862 | */ | |
863 | bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, | |
864 | const unsigned long *mask) | |
865 | { | |
866 | return bitmap_weight(mask, indio_dev->masklength) == 1; | |
867 | } | |
868 | EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot); | |
869 | ||
f79a9098 JC |
870 | int iio_scan_mask_query(struct iio_dev *indio_dev, |
871 | struct iio_buffer *buffer, int bit) | |
32b5eeca | 872 | { |
f8c6f4e9 | 873 | if (bit > indio_dev->masklength) |
32b5eeca JC |
874 | return -EINVAL; |
875 | ||
14555b14 | 876 | if (!buffer->scan_mask) |
32b5eeca | 877 | return 0; |
32b5eeca | 878 | |
2076a20f AB |
879 | /* Ensure return value is 0 or 1. */ |
880 | return !!test_bit(bit, buffer->scan_mask); | |
32b5eeca JC |
881 | }; |
882 | EXPORT_SYMBOL_GPL(iio_scan_mask_query); | |
5ada4ea9 JC |
883 | |
884 | /** | |
885 | * struct iio_demux_table() - table describing demux memcpy ops | |
886 | * @from: index to copy from | |
99698b45 | 887 | * @to: index to copy to |
5ada4ea9 JC |
888 | * @length: how many bytes to copy |
889 | * @l: list head used for management | |
890 | */ | |
891 | struct iio_demux_table { | |
892 | unsigned from; | |
893 | unsigned to; | |
894 | unsigned length; | |
895 | struct list_head l; | |
896 | }; | |
897 | ||
5d65d920 LPC |
898 | static const void *iio_demux(struct iio_buffer *buffer, |
899 | const void *datain) | |
5ada4ea9 JC |
900 | { |
901 | struct iio_demux_table *t; | |
902 | ||
903 | if (list_empty(&buffer->demux_list)) | |
904 | return datain; | |
905 | list_for_each_entry(t, &buffer->demux_list, l) | |
906 | memcpy(buffer->demux_bounce + t->to, | |
907 | datain + t->from, t->length); | |
908 | ||
909 | return buffer->demux_bounce; | |
910 | } | |
911 | ||
5d65d920 | 912 | static int iio_push_to_buffer(struct iio_buffer *buffer, const void *data) |
5ada4ea9 | 913 | { |
5d65d920 | 914 | const void *dataout = iio_demux(buffer, data); |
5ada4ea9 | 915 | |
ce56ade6 | 916 | return buffer->access->store_to(buffer, dataout); |
5ada4ea9 | 917 | } |
5ada4ea9 | 918 | |
842cd100 JC |
919 | static void iio_buffer_demux_free(struct iio_buffer *buffer) |
920 | { | |
921 | struct iio_demux_table *p, *q; | |
922 | list_for_each_entry_safe(p, q, &buffer->demux_list, l) { | |
923 | list_del(&p->l); | |
924 | kfree(p); | |
925 | } | |
926 | } | |
927 | ||
84b36ce5 | 928 | |
5d65d920 | 929 | int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data) |
84b36ce5 JC |
930 | { |
931 | int ret; | |
932 | struct iio_buffer *buf; | |
933 | ||
934 | list_for_each_entry(buf, &indio_dev->buffer_list, buffer_list) { | |
935 | ret = iio_push_to_buffer(buf, data); | |
936 | if (ret < 0) | |
937 | return ret; | |
938 | } | |
939 | ||
940 | return 0; | |
941 | } | |
942 | EXPORT_SYMBOL_GPL(iio_push_to_buffers); | |
943 | ||
cbe88bcc LPC |
944 | static int iio_buffer_add_demux(struct iio_buffer *buffer, |
945 | struct iio_demux_table **p, unsigned int in_loc, unsigned int out_loc, | |
946 | unsigned int length) | |
947 | { | |
948 | ||
949 | if (*p && (*p)->from + (*p)->length == in_loc && | |
950 | (*p)->to + (*p)->length == out_loc) { | |
951 | (*p)->length += length; | |
952 | } else { | |
7cdca178 | 953 | *p = kmalloc(sizeof(**p), GFP_KERNEL); |
cbe88bcc LPC |
954 | if (*p == NULL) |
955 | return -ENOMEM; | |
956 | (*p)->from = in_loc; | |
957 | (*p)->to = out_loc; | |
958 | (*p)->length = length; | |
959 | list_add_tail(&(*p)->l, &buffer->demux_list); | |
960 | } | |
961 | ||
962 | return 0; | |
963 | } | |
964 | ||
84b36ce5 JC |
965 | static int iio_buffer_update_demux(struct iio_dev *indio_dev, |
966 | struct iio_buffer *buffer) | |
5ada4ea9 JC |
967 | { |
968 | const struct iio_chan_spec *ch; | |
5ada4ea9 JC |
969 | int ret, in_ind = -1, out_ind, length; |
970 | unsigned in_loc = 0, out_loc = 0; | |
cbe88bcc | 971 | struct iio_demux_table *p = NULL; |
5ada4ea9 JC |
972 | |
973 | /* Clear out any old demux */ | |
842cd100 | 974 | iio_buffer_demux_free(buffer); |
5ada4ea9 JC |
975 | kfree(buffer->demux_bounce); |
976 | buffer->demux_bounce = NULL; | |
977 | ||
978 | /* First work out which scan mode we will actually have */ | |
979 | if (bitmap_equal(indio_dev->active_scan_mask, | |
980 | buffer->scan_mask, | |
981 | indio_dev->masklength)) | |
982 | return 0; | |
983 | ||
984 | /* Now we have the two masks, work from least sig and build up sizes */ | |
985 | for_each_set_bit(out_ind, | |
61bd55ce | 986 | buffer->scan_mask, |
5ada4ea9 JC |
987 | indio_dev->masklength) { |
988 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
989 | indio_dev->masklength, | |
990 | in_ind + 1); | |
991 | while (in_ind != out_ind) { | |
992 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
993 | indio_dev->masklength, | |
994 | in_ind + 1); | |
995 | ch = iio_find_channel_from_si(indio_dev, in_ind); | |
0ee8546a SP |
996 | if (ch->scan_type.repeat > 1) |
997 | length = ch->scan_type.storagebits / 8 * | |
998 | ch->scan_type.repeat; | |
999 | else | |
1000 | length = ch->scan_type.storagebits / 8; | |
5ada4ea9 | 1001 | /* Make sure we are aligned */ |
61072dbc | 1002 | in_loc = roundup(in_loc, length) + length; |
5ada4ea9 JC |
1003 | } |
1004 | ch = iio_find_channel_from_si(indio_dev, in_ind); | |
0ee8546a SP |
1005 | if (ch->scan_type.repeat > 1) |
1006 | length = ch->scan_type.storagebits / 8 * | |
1007 | ch->scan_type.repeat; | |
1008 | else | |
1009 | length = ch->scan_type.storagebits / 8; | |
61072dbc LPC |
1010 | out_loc = roundup(out_loc, length); |
1011 | in_loc = roundup(in_loc, length); | |
cbe88bcc LPC |
1012 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); |
1013 | if (ret) | |
1014 | goto error_clear_mux_table; | |
5ada4ea9 JC |
1015 | out_loc += length; |
1016 | in_loc += length; | |
1017 | } | |
1018 | /* Relies on scan_timestamp being last */ | |
1019 | if (buffer->scan_timestamp) { | |
5ada4ea9 | 1020 | ch = iio_find_channel_from_si(indio_dev, |
f1264809 | 1021 | indio_dev->scan_index_timestamp); |
0ee8546a SP |
1022 | if (ch->scan_type.repeat > 1) |
1023 | length = ch->scan_type.storagebits / 8 * | |
1024 | ch->scan_type.repeat; | |
1025 | else | |
1026 | length = ch->scan_type.storagebits / 8; | |
61072dbc LPC |
1027 | out_loc = roundup(out_loc, length); |
1028 | in_loc = roundup(in_loc, length); | |
cbe88bcc LPC |
1029 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); |
1030 | if (ret) | |
1031 | goto error_clear_mux_table; | |
5ada4ea9 JC |
1032 | out_loc += length; |
1033 | in_loc += length; | |
1034 | } | |
1035 | buffer->demux_bounce = kzalloc(out_loc, GFP_KERNEL); | |
1036 | if (buffer->demux_bounce == NULL) { | |
1037 | ret = -ENOMEM; | |
1038 | goto error_clear_mux_table; | |
1039 | } | |
1040 | return 0; | |
1041 | ||
1042 | error_clear_mux_table: | |
842cd100 JC |
1043 | iio_buffer_demux_free(buffer); |
1044 | ||
5ada4ea9 JC |
1045 | return ret; |
1046 | } | |
84b36ce5 JC |
1047 | |
1048 | int iio_update_demux(struct iio_dev *indio_dev) | |
1049 | { | |
1050 | struct iio_buffer *buffer; | |
1051 | int ret; | |
1052 | ||
1053 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
1054 | ret = iio_buffer_update_demux(indio_dev, buffer); | |
1055 | if (ret < 0) | |
1056 | goto error_clear_mux_table; | |
1057 | } | |
1058 | return 0; | |
1059 | ||
1060 | error_clear_mux_table: | |
1061 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) | |
1062 | iio_buffer_demux_free(buffer); | |
1063 | ||
1064 | return ret; | |
1065 | } | |
5ada4ea9 | 1066 | EXPORT_SYMBOL_GPL(iio_update_demux); |
9e69c935 LPC |
1067 | |
1068 | /** | |
1069 | * iio_buffer_release() - Free a buffer's resources | |
1070 | * @ref: Pointer to the kref embedded in the iio_buffer struct | |
1071 | * | |
1072 | * This function is called when the last reference to the buffer has been | |
1073 | * dropped. It will typically free all resources allocated by the buffer. Do not | |
1074 | * call this function manually, always use iio_buffer_put() when done using a | |
1075 | * buffer. | |
1076 | */ | |
1077 | static void iio_buffer_release(struct kref *ref) | |
1078 | { | |
1079 | struct iio_buffer *buffer = container_of(ref, struct iio_buffer, ref); | |
1080 | ||
1081 | buffer->access->release(buffer); | |
1082 | } | |
1083 | ||
1084 | /** | |
1085 | * iio_buffer_get() - Grab a reference to the buffer | |
1086 | * @buffer: The buffer to grab a reference for, may be NULL | |
1087 | * | |
1088 | * Returns the pointer to the buffer that was passed into the function. | |
1089 | */ | |
1090 | struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer) | |
1091 | { | |
1092 | if (buffer) | |
1093 | kref_get(&buffer->ref); | |
1094 | ||
1095 | return buffer; | |
1096 | } | |
1097 | EXPORT_SYMBOL_GPL(iio_buffer_get); | |
1098 | ||
1099 | /** | |
1100 | * iio_buffer_put() - Release the reference to the buffer | |
1101 | * @buffer: The buffer to release the reference for, may be NULL | |
1102 | */ | |
1103 | void iio_buffer_put(struct iio_buffer *buffer) | |
1104 | { | |
1105 | if (buffer) | |
1106 | kref_put(&buffer->ref, iio_buffer_release); | |
1107 | } | |
1108 | EXPORT_SYMBOL_GPL(iio_buffer_put); |