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 | ||
37d34556 | 40 | static size_t iio_buffer_data_available(struct iio_buffer *buf) |
647cc7b9 | 41 | { |
9dd4694d | 42 | return buf->access->data_available(buf); |
647cc7b9 LPC |
43 | } |
44 | ||
f4f4673b OP |
45 | static int iio_buffer_flush_hwfifo(struct iio_dev *indio_dev, |
46 | struct iio_buffer *buf, size_t required) | |
47 | { | |
48 | if (!indio_dev->info->hwfifo_flush_to_buffer) | |
49 | return -ENODEV; | |
50 | ||
51 | return indio_dev->info->hwfifo_flush_to_buffer(indio_dev, required); | |
52 | } | |
53 | ||
37d34556 | 54 | static bool iio_buffer_ready(struct iio_dev *indio_dev, struct iio_buffer *buf, |
f4f4673b | 55 | size_t to_wait, int to_flush) |
37d34556 | 56 | { |
f4f4673b OP |
57 | size_t avail; |
58 | int flushed = 0; | |
59 | ||
37d34556 JC |
60 | /* wakeup if the device was unregistered */ |
61 | if (!indio_dev->info) | |
62 | return true; | |
63 | ||
64 | /* drain the buffer if it was disabled */ | |
f4f4673b | 65 | if (!iio_buffer_is_active(buf)) { |
37d34556 | 66 | to_wait = min_t(size_t, to_wait, 1); |
f4f4673b OP |
67 | to_flush = 0; |
68 | } | |
69 | ||
70 | avail = iio_buffer_data_available(buf); | |
37d34556 | 71 | |
f4f4673b OP |
72 | if (avail >= to_wait) { |
73 | /* force a flush for non-blocking reads */ | |
74 | if (!to_wait && !avail && to_flush) | |
75 | iio_buffer_flush_hwfifo(indio_dev, buf, to_flush); | |
76 | return true; | |
77 | } | |
78 | ||
79 | if (to_flush) | |
80 | flushed = iio_buffer_flush_hwfifo(indio_dev, buf, | |
81 | to_wait - avail); | |
82 | if (flushed <= 0) | |
83 | return false; | |
84 | ||
85 | if (avail + flushed >= to_wait) | |
37d34556 JC |
86 | return true; |
87 | ||
88 | return false; | |
89 | } | |
90 | ||
7026ea4b | 91 | /** |
14555b14 | 92 | * iio_buffer_read_first_n_outer() - chrdev read for buffer access |
7026ea4b | 93 | * |
14555b14 JC |
94 | * This function relies on all buffer implementations having an |
95 | * iio_buffer as their first element. | |
7026ea4b | 96 | **/ |
14555b14 JC |
97 | ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf, |
98 | size_t n, loff_t *f_ps) | |
7026ea4b | 99 | { |
1aa04278 | 100 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 101 | struct iio_buffer *rb = indio_dev->buffer; |
37d34556 JC |
102 | size_t datum_size; |
103 | size_t to_wait = 0; | |
f4f4673b | 104 | size_t to_read; |
ee551a10 | 105 | int ret; |
d5857d65 | 106 | |
f18e7a06 LPC |
107 | if (!indio_dev->info) |
108 | return -ENODEV; | |
109 | ||
96e00f11 | 110 | if (!rb || !rb->access->read_first_n) |
7026ea4b | 111 | return -EINVAL; |
ee551a10 | 112 | |
37d34556 JC |
113 | datum_size = rb->bytes_per_datum; |
114 | ||
115 | /* | |
116 | * If datum_size is 0 there will never be anything to read from the | |
117 | * buffer, so signal end of file now. | |
118 | */ | |
119 | if (!datum_size) | |
120 | return 0; | |
121 | ||
f4f4673b OP |
122 | to_read = min_t(size_t, n / datum_size, rb->watermark); |
123 | ||
37d34556 | 124 | if (!(filp->f_flags & O_NONBLOCK)) |
f4f4673b | 125 | to_wait = to_read; |
37d34556 | 126 | |
ee551a10 | 127 | do { |
37d34556 | 128 | ret = wait_event_interruptible(rb->pollq, |
f4f4673b | 129 | iio_buffer_ready(indio_dev, rb, to_wait, to_read)); |
37d34556 JC |
130 | if (ret) |
131 | return ret; | |
ee551a10 | 132 | |
37d34556 JC |
133 | if (!indio_dev->info) |
134 | return -ENODEV; | |
ee551a10 LPC |
135 | |
136 | ret = rb->access->read_first_n(rb, n, buf); | |
137 | if (ret == 0 && (filp->f_flags & O_NONBLOCK)) | |
138 | ret = -EAGAIN; | |
139 | } while (ret == 0); | |
140 | ||
141 | return ret; | |
7026ea4b JC |
142 | } |
143 | ||
a7348347 | 144 | /** |
14555b14 | 145 | * iio_buffer_poll() - poll the buffer to find out if it has data |
a7348347 | 146 | */ |
14555b14 JC |
147 | unsigned int iio_buffer_poll(struct file *filp, |
148 | struct poll_table_struct *wait) | |
a7348347 | 149 | { |
1aa04278 | 150 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 151 | struct iio_buffer *rb = indio_dev->buffer; |
a7348347 | 152 | |
f18e7a06 LPC |
153 | if (!indio_dev->info) |
154 | return -ENODEV; | |
155 | ||
a7348347 | 156 | poll_wait(filp, &rb->pollq, wait); |
f4f4673b | 157 | if (iio_buffer_ready(indio_dev, rb, rb->watermark, 0)) |
a7348347 | 158 | return POLLIN | POLLRDNORM; |
8d213f24 | 159 | return 0; |
a7348347 JC |
160 | } |
161 | ||
d2f0a48f LPC |
162 | /** |
163 | * iio_buffer_wakeup_poll - Wakes up the buffer waitqueue | |
164 | * @indio_dev: The IIO device | |
165 | * | |
166 | * Wakes up the event waitqueue used for poll(). Should usually | |
167 | * be called when the device is unregistered. | |
168 | */ | |
169 | void iio_buffer_wakeup_poll(struct iio_dev *indio_dev) | |
170 | { | |
171 | if (!indio_dev->buffer) | |
172 | return; | |
173 | ||
174 | wake_up(&indio_dev->buffer->pollq); | |
175 | } | |
176 | ||
f79a9098 | 177 | void iio_buffer_init(struct iio_buffer *buffer) |
7026ea4b | 178 | { |
5ada4ea9 | 179 | INIT_LIST_HEAD(&buffer->demux_list); |
705ee2c9 | 180 | INIT_LIST_HEAD(&buffer->buffer_list); |
14555b14 | 181 | init_waitqueue_head(&buffer->pollq); |
9e69c935 | 182 | kref_init(&buffer->ref); |
37d34556 | 183 | buffer->watermark = 1; |
7026ea4b | 184 | } |
14555b14 | 185 | EXPORT_SYMBOL(iio_buffer_init); |
7026ea4b | 186 | |
1d892719 | 187 | static ssize_t iio_show_scan_index(struct device *dev, |
8d213f24 JC |
188 | struct device_attribute *attr, |
189 | char *buf) | |
1d892719 | 190 | { |
8d213f24 | 191 | return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index); |
1d892719 JC |
192 | } |
193 | ||
194 | static ssize_t iio_show_fixed_type(struct device *dev, | |
195 | struct device_attribute *attr, | |
196 | char *buf) | |
197 | { | |
198 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); | |
8310b86c JC |
199 | u8 type = this_attr->c->scan_type.endianness; |
200 | ||
201 | if (type == IIO_CPU) { | |
9d5d1153 JC |
202 | #ifdef __LITTLE_ENDIAN |
203 | type = IIO_LE; | |
204 | #else | |
205 | type = IIO_BE; | |
206 | #endif | |
8310b86c | 207 | } |
0ee8546a SP |
208 | if (this_attr->c->scan_type.repeat > 1) |
209 | return sprintf(buf, "%s:%c%d/%dX%d>>%u\n", | |
210 | iio_endian_prefix[type], | |
211 | this_attr->c->scan_type.sign, | |
212 | this_attr->c->scan_type.realbits, | |
213 | this_attr->c->scan_type.storagebits, | |
214 | this_attr->c->scan_type.repeat, | |
215 | this_attr->c->scan_type.shift); | |
216 | else | |
217 | return sprintf(buf, "%s:%c%d/%d>>%u\n", | |
8310b86c | 218 | iio_endian_prefix[type], |
1d892719 JC |
219 | this_attr->c->scan_type.sign, |
220 | this_attr->c->scan_type.realbits, | |
221 | this_attr->c->scan_type.storagebits, | |
222 | this_attr->c->scan_type.shift); | |
223 | } | |
224 | ||
8d213f24 JC |
225 | static ssize_t iio_scan_el_show(struct device *dev, |
226 | struct device_attribute *attr, | |
227 | char *buf) | |
228 | { | |
229 | int ret; | |
e53f5ac5 | 230 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 231 | |
2076a20f AB |
232 | /* Ensure ret is 0 or 1. */ |
233 | ret = !!test_bit(to_iio_dev_attr(attr)->address, | |
5ada4ea9 JC |
234 | indio_dev->buffer->scan_mask); |
235 | ||
8d213f24 JC |
236 | return sprintf(buf, "%d\n", ret); |
237 | } | |
238 | ||
217a5cf0 LPC |
239 | /* Note NULL used as error indicator as it doesn't make sense. */ |
240 | static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks, | |
241 | unsigned int masklength, | |
242 | const unsigned long *mask) | |
243 | { | |
244 | if (bitmap_empty(mask, masklength)) | |
245 | return NULL; | |
246 | while (*av_masks) { | |
247 | if (bitmap_subset(mask, av_masks, masklength)) | |
248 | return av_masks; | |
249 | av_masks += BITS_TO_LONGS(masklength); | |
250 | } | |
251 | return NULL; | |
252 | } | |
253 | ||
254 | static bool iio_validate_scan_mask(struct iio_dev *indio_dev, | |
255 | const unsigned long *mask) | |
256 | { | |
257 | if (!indio_dev->setup_ops->validate_scan_mask) | |
258 | return true; | |
259 | ||
260 | return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask); | |
261 | } | |
262 | ||
263 | /** | |
264 | * iio_scan_mask_set() - set particular bit in the scan mask | |
265 | * @indio_dev: the iio device | |
266 | * @buffer: the buffer whose scan mask we are interested in | |
267 | * @bit: the bit to be set. | |
268 | * | |
269 | * Note that at this point we have no way of knowing what other | |
270 | * buffers might request, hence this code only verifies that the | |
271 | * individual buffers request is plausible. | |
272 | */ | |
273 | static int iio_scan_mask_set(struct iio_dev *indio_dev, | |
274 | struct iio_buffer *buffer, int bit) | |
275 | { | |
276 | const unsigned long *mask; | |
277 | unsigned long *trialmask; | |
278 | ||
279 | trialmask = kmalloc(sizeof(*trialmask)* | |
280 | BITS_TO_LONGS(indio_dev->masklength), | |
281 | GFP_KERNEL); | |
282 | ||
283 | if (trialmask == NULL) | |
284 | return -ENOMEM; | |
285 | if (!indio_dev->masklength) { | |
286 | WARN_ON("Trying to set scanmask prior to registering buffer\n"); | |
287 | goto err_invalid_mask; | |
288 | } | |
289 | bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength); | |
290 | set_bit(bit, trialmask); | |
291 | ||
292 | if (!iio_validate_scan_mask(indio_dev, trialmask)) | |
293 | goto err_invalid_mask; | |
294 | ||
295 | if (indio_dev->available_scan_masks) { | |
296 | mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
297 | indio_dev->masklength, | |
298 | trialmask); | |
299 | if (!mask) | |
300 | goto err_invalid_mask; | |
301 | } | |
302 | bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength); | |
303 | ||
304 | kfree(trialmask); | |
305 | ||
306 | return 0; | |
307 | ||
308 | err_invalid_mask: | |
309 | kfree(trialmask); | |
310 | return -EINVAL; | |
311 | } | |
312 | ||
14555b14 | 313 | static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit) |
8d213f24 | 314 | { |
14555b14 | 315 | clear_bit(bit, buffer->scan_mask); |
8d213f24 JC |
316 | return 0; |
317 | } | |
318 | ||
319 | static ssize_t iio_scan_el_store(struct device *dev, | |
320 | struct device_attribute *attr, | |
321 | const char *buf, | |
322 | size_t len) | |
323 | { | |
a714af27 | 324 | int ret; |
8d213f24 | 325 | bool state; |
e53f5ac5 | 326 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 327 | struct iio_buffer *buffer = indio_dev->buffer; |
8d213f24 JC |
328 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
329 | ||
a714af27 JC |
330 | ret = strtobool(buf, &state); |
331 | if (ret < 0) | |
332 | return ret; | |
8d213f24 | 333 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 334 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
335 | ret = -EBUSY; |
336 | goto error_ret; | |
337 | } | |
f79a9098 | 338 | ret = iio_scan_mask_query(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
339 | if (ret < 0) |
340 | goto error_ret; | |
341 | if (!state && ret) { | |
14555b14 | 342 | ret = iio_scan_mask_clear(buffer, this_attr->address); |
8d213f24 JC |
343 | if (ret) |
344 | goto error_ret; | |
345 | } else if (state && !ret) { | |
f79a9098 | 346 | ret = iio_scan_mask_set(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
347 | if (ret) |
348 | goto error_ret; | |
349 | } | |
350 | ||
351 | error_ret: | |
352 | mutex_unlock(&indio_dev->mlock); | |
353 | ||
5a2a6e11 | 354 | return ret < 0 ? ret : len; |
8d213f24 JC |
355 | |
356 | } | |
357 | ||
358 | static ssize_t iio_scan_el_ts_show(struct device *dev, | |
359 | struct device_attribute *attr, | |
360 | char *buf) | |
361 | { | |
e53f5ac5 | 362 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
f8c6f4e9 | 363 | return sprintf(buf, "%d\n", indio_dev->buffer->scan_timestamp); |
8d213f24 JC |
364 | } |
365 | ||
366 | static ssize_t iio_scan_el_ts_store(struct device *dev, | |
367 | struct device_attribute *attr, | |
368 | const char *buf, | |
369 | size_t len) | |
370 | { | |
a714af27 | 371 | int ret; |
e53f5ac5 | 372 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 373 | bool state; |
1aa04278 | 374 | |
a714af27 JC |
375 | ret = strtobool(buf, &state); |
376 | if (ret < 0) | |
377 | return ret; | |
378 | ||
8d213f24 | 379 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 380 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
381 | ret = -EBUSY; |
382 | goto error_ret; | |
383 | } | |
14555b14 | 384 | indio_dev->buffer->scan_timestamp = state; |
8d213f24 JC |
385 | error_ret: |
386 | mutex_unlock(&indio_dev->mlock); | |
387 | ||
388 | return ret ? ret : len; | |
389 | } | |
390 | ||
14555b14 JC |
391 | static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev, |
392 | const struct iio_chan_spec *chan) | |
1d892719 | 393 | { |
26d25ae3 | 394 | int ret, attrcount = 0; |
14555b14 | 395 | struct iio_buffer *buffer = indio_dev->buffer; |
1d892719 | 396 | |
26d25ae3 | 397 | ret = __iio_add_chan_devattr("index", |
1d892719 JC |
398 | chan, |
399 | &iio_show_scan_index, | |
400 | NULL, | |
401 | 0, | |
3704432f | 402 | IIO_SEPARATE, |
1aa04278 | 403 | &indio_dev->dev, |
14555b14 | 404 | &buffer->scan_el_dev_attr_list); |
1d892719 | 405 | if (ret) |
92825ff9 | 406 | return ret; |
26d25ae3 JC |
407 | attrcount++; |
408 | ret = __iio_add_chan_devattr("type", | |
1d892719 JC |
409 | chan, |
410 | &iio_show_fixed_type, | |
411 | NULL, | |
412 | 0, | |
413 | 0, | |
1aa04278 | 414 | &indio_dev->dev, |
14555b14 | 415 | &buffer->scan_el_dev_attr_list); |
1d892719 | 416 | if (ret) |
92825ff9 | 417 | return ret; |
26d25ae3 | 418 | attrcount++; |
a88b3ebc | 419 | if (chan->type != IIO_TIMESTAMP) |
26d25ae3 | 420 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
421 | chan, |
422 | &iio_scan_el_show, | |
423 | &iio_scan_el_store, | |
424 | chan->scan_index, | |
425 | 0, | |
1aa04278 | 426 | &indio_dev->dev, |
14555b14 | 427 | &buffer->scan_el_dev_attr_list); |
a88b3ebc | 428 | else |
26d25ae3 | 429 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
430 | chan, |
431 | &iio_scan_el_ts_show, | |
432 | &iio_scan_el_ts_store, | |
433 | chan->scan_index, | |
434 | 0, | |
1aa04278 | 435 | &indio_dev->dev, |
14555b14 | 436 | &buffer->scan_el_dev_attr_list); |
9572588c | 437 | if (ret) |
92825ff9 | 438 | return ret; |
26d25ae3 JC |
439 | attrcount++; |
440 | ret = attrcount; | |
1d892719 JC |
441 | return ret; |
442 | } | |
443 | ||
08e7e0ad LPC |
444 | static ssize_t iio_buffer_read_length(struct device *dev, |
445 | struct device_attribute *attr, | |
446 | char *buf) | |
7026ea4b | 447 | { |
e53f5ac5 | 448 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 449 | struct iio_buffer *buffer = indio_dev->buffer; |
7026ea4b | 450 | |
37495660 | 451 | return sprintf(buf, "%d\n", buffer->length); |
7026ea4b | 452 | } |
7026ea4b | 453 | |
08e7e0ad LPC |
454 | static ssize_t iio_buffer_write_length(struct device *dev, |
455 | struct device_attribute *attr, | |
456 | const char *buf, size_t len) | |
7026ea4b | 457 | { |
e53f5ac5 | 458 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 459 | struct iio_buffer *buffer = indio_dev->buffer; |
948ad205 LPC |
460 | unsigned int val; |
461 | int ret; | |
8d213f24 | 462 | |
948ad205 | 463 | ret = kstrtouint(buf, 10, &val); |
7026ea4b JC |
464 | if (ret) |
465 | return ret; | |
466 | ||
37495660 LPC |
467 | if (val == buffer->length) |
468 | return len; | |
7026ea4b | 469 | |
e38c79e0 | 470 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 471 | if (iio_buffer_is_active(indio_dev->buffer)) { |
e38c79e0 LPC |
472 | ret = -EBUSY; |
473 | } else { | |
8d92db28 | 474 | buffer->access->set_length(buffer, val); |
e38c79e0 | 475 | ret = 0; |
7026ea4b | 476 | } |
37d34556 JC |
477 | if (ret) |
478 | goto out; | |
479 | if (buffer->length && buffer->length < buffer->watermark) | |
480 | buffer->watermark = buffer->length; | |
481 | out: | |
e38c79e0 | 482 | mutex_unlock(&indio_dev->mlock); |
7026ea4b | 483 | |
e38c79e0 | 484 | return ret ? ret : len; |
7026ea4b | 485 | } |
7026ea4b | 486 | |
08e7e0ad LPC |
487 | static ssize_t iio_buffer_show_enable(struct device *dev, |
488 | struct device_attribute *attr, | |
489 | char *buf) | |
7026ea4b | 490 | { |
e53f5ac5 | 491 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
705ee2c9 | 492 | return sprintf(buf, "%d\n", iio_buffer_is_active(indio_dev->buffer)); |
7026ea4b | 493 | } |
7026ea4b | 494 | |
183f4173 PM |
495 | static int iio_compute_scan_bytes(struct iio_dev *indio_dev, |
496 | const unsigned long *mask, bool timestamp) | |
959d2952 | 497 | { |
959d2952 JC |
498 | const struct iio_chan_spec *ch; |
499 | unsigned bytes = 0; | |
500 | int length, i; | |
959d2952 JC |
501 | |
502 | /* How much space will the demuxed element take? */ | |
6b3b58ed | 503 | for_each_set_bit(i, mask, |
959d2952 JC |
504 | indio_dev->masklength) { |
505 | ch = iio_find_channel_from_si(indio_dev, i); | |
0ee8546a SP |
506 | if (ch->scan_type.repeat > 1) |
507 | length = ch->scan_type.storagebits / 8 * | |
508 | ch->scan_type.repeat; | |
509 | else | |
510 | length = ch->scan_type.storagebits / 8; | |
959d2952 JC |
511 | bytes = ALIGN(bytes, length); |
512 | bytes += length; | |
513 | } | |
6b3b58ed | 514 | if (timestamp) { |
959d2952 | 515 | ch = iio_find_channel_from_si(indio_dev, |
f1264809 | 516 | indio_dev->scan_index_timestamp); |
0ee8546a SP |
517 | if (ch->scan_type.repeat > 1) |
518 | length = ch->scan_type.storagebits / 8 * | |
519 | ch->scan_type.repeat; | |
520 | else | |
521 | length = ch->scan_type.storagebits / 8; | |
959d2952 JC |
522 | bytes = ALIGN(bytes, length); |
523 | bytes += length; | |
524 | } | |
6b3b58ed JC |
525 | return bytes; |
526 | } | |
527 | ||
9e69c935 LPC |
528 | static void iio_buffer_activate(struct iio_dev *indio_dev, |
529 | struct iio_buffer *buffer) | |
530 | { | |
531 | iio_buffer_get(buffer); | |
532 | list_add(&buffer->buffer_list, &indio_dev->buffer_list); | |
533 | } | |
534 | ||
535 | static void iio_buffer_deactivate(struct iio_buffer *buffer) | |
536 | { | |
537 | list_del_init(&buffer->buffer_list); | |
37d34556 | 538 | wake_up_interruptible(&buffer->pollq); |
9e69c935 LPC |
539 | iio_buffer_put(buffer); |
540 | } | |
541 | ||
a87c82e4 LPC |
542 | void iio_disable_all_buffers(struct iio_dev *indio_dev) |
543 | { | |
544 | struct iio_buffer *buffer, *_buffer; | |
545 | ||
546 | if (list_empty(&indio_dev->buffer_list)) | |
547 | return; | |
548 | ||
549 | if (indio_dev->setup_ops->predisable) | |
550 | indio_dev->setup_ops->predisable(indio_dev); | |
551 | ||
552 | list_for_each_entry_safe(buffer, _buffer, | |
553 | &indio_dev->buffer_list, buffer_list) | |
9e69c935 | 554 | iio_buffer_deactivate(buffer); |
a87c82e4 LPC |
555 | |
556 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
557 | if (indio_dev->setup_ops->postdisable) | |
558 | indio_dev->setup_ops->postdisable(indio_dev); | |
e086ed76 LPC |
559 | |
560 | if (indio_dev->available_scan_masks == NULL) | |
561 | kfree(indio_dev->active_scan_mask); | |
a87c82e4 LPC |
562 | } |
563 | ||
8e050996 LPC |
564 | static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev, |
565 | struct iio_buffer *buffer) | |
566 | { | |
567 | unsigned int bytes; | |
568 | ||
569 | if (!buffer->access->set_bytes_per_datum) | |
570 | return; | |
571 | ||
572 | bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask, | |
573 | buffer->scan_timestamp); | |
574 | ||
575 | buffer->access->set_bytes_per_datum(buffer, bytes); | |
576 | } | |
577 | ||
a9519456 | 578 | static int __iio_update_buffers(struct iio_dev *indio_dev, |
84b36ce5 JC |
579 | struct iio_buffer *insert_buffer, |
580 | struct iio_buffer *remove_buffer) | |
6b3b58ed | 581 | { |
84b36ce5 JC |
582 | int ret; |
583 | int success = 0; | |
584 | struct iio_buffer *buffer; | |
585 | unsigned long *compound_mask; | |
586 | const unsigned long *old_mask; | |
6b3b58ed | 587 | |
84b36ce5 JC |
588 | /* Wind down existing buffers - iff there are any */ |
589 | if (!list_empty(&indio_dev->buffer_list)) { | |
590 | if (indio_dev->setup_ops->predisable) { | |
591 | ret = indio_dev->setup_ops->predisable(indio_dev); | |
592 | if (ret) | |
92825ff9 | 593 | return ret; |
84b36ce5 JC |
594 | } |
595 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
596 | if (indio_dev->setup_ops->postdisable) { | |
597 | ret = indio_dev->setup_ops->postdisable(indio_dev); | |
598 | if (ret) | |
92825ff9 | 599 | return ret; |
84b36ce5 JC |
600 | } |
601 | } | |
602 | /* Keep a copy of current setup to allow roll back */ | |
603 | old_mask = indio_dev->active_scan_mask; | |
604 | if (!indio_dev->available_scan_masks) | |
605 | indio_dev->active_scan_mask = NULL; | |
606 | ||
607 | if (remove_buffer) | |
9e69c935 | 608 | iio_buffer_deactivate(remove_buffer); |
84b36ce5 | 609 | if (insert_buffer) |
9e69c935 | 610 | iio_buffer_activate(indio_dev, insert_buffer); |
84b36ce5 JC |
611 | |
612 | /* If no buffers in list, we are done */ | |
613 | if (list_empty(&indio_dev->buffer_list)) { | |
614 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
615 | if (indio_dev->available_scan_masks == NULL) | |
616 | kfree(old_mask); | |
617 | return 0; | |
618 | } | |
959d2952 | 619 | |
9572588c | 620 | /* What scan mask do we actually have? */ |
84b36ce5 JC |
621 | compound_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), |
622 | sizeof(long), GFP_KERNEL); | |
623 | if (compound_mask == NULL) { | |
624 | if (indio_dev->available_scan_masks == NULL) | |
625 | kfree(old_mask); | |
626 | return -ENOMEM; | |
627 | } | |
628 | indio_dev->scan_timestamp = 0; | |
629 | ||
630 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
631 | bitmap_or(compound_mask, compound_mask, buffer->scan_mask, | |
632 | indio_dev->masklength); | |
633 | indio_dev->scan_timestamp |= buffer->scan_timestamp; | |
634 | } | |
635 | if (indio_dev->available_scan_masks) { | |
959d2952 JC |
636 | indio_dev->active_scan_mask = |
637 | iio_scan_mask_match(indio_dev->available_scan_masks, | |
638 | indio_dev->masklength, | |
84b36ce5 JC |
639 | compound_mask); |
640 | if (indio_dev->active_scan_mask == NULL) { | |
641 | /* | |
642 | * Roll back. | |
643 | * Note can only occur when adding a buffer. | |
644 | */ | |
9e69c935 | 645 | iio_buffer_deactivate(insert_buffer); |
d66e0452 PM |
646 | if (old_mask) { |
647 | indio_dev->active_scan_mask = old_mask; | |
648 | success = -EINVAL; | |
649 | } | |
650 | else { | |
651 | kfree(compound_mask); | |
652 | ret = -EINVAL; | |
92825ff9 | 653 | return ret; |
d66e0452 | 654 | } |
84b36ce5 JC |
655 | } |
656 | } else { | |
657 | indio_dev->active_scan_mask = compound_mask; | |
658 | } | |
aff1eb4e | 659 | |
5ada4ea9 JC |
660 | iio_update_demux(indio_dev); |
661 | ||
84b36ce5 JC |
662 | /* Wind up again */ |
663 | if (indio_dev->setup_ops->preenable) { | |
664 | ret = indio_dev->setup_ops->preenable(indio_dev); | |
665 | if (ret) { | |
666 | printk(KERN_ERR | |
bec1889d | 667 | "Buffer not started: buffer preenable failed (%d)\n", ret); |
84b36ce5 JC |
668 | goto error_remove_inserted; |
669 | } | |
670 | } | |
671 | indio_dev->scan_bytes = | |
672 | iio_compute_scan_bytes(indio_dev, | |
673 | indio_dev->active_scan_mask, | |
674 | indio_dev->scan_timestamp); | |
8e050996 LPC |
675 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { |
676 | iio_buffer_update_bytes_per_datum(indio_dev, buffer); | |
84b36ce5 JC |
677 | if (buffer->access->request_update) { |
678 | ret = buffer->access->request_update(buffer); | |
679 | if (ret) { | |
680 | printk(KERN_INFO | |
bec1889d | 681 | "Buffer not started: buffer parameter update failed (%d)\n", ret); |
84b36ce5 JC |
682 | goto error_run_postdisable; |
683 | } | |
684 | } | |
8e050996 | 685 | } |
84b36ce5 JC |
686 | if (indio_dev->info->update_scan_mode) { |
687 | ret = indio_dev->info | |
5ada4ea9 JC |
688 | ->update_scan_mode(indio_dev, |
689 | indio_dev->active_scan_mask); | |
84b36ce5 | 690 | if (ret < 0) { |
bec1889d | 691 | printk(KERN_INFO "Buffer not started: update scan mode failed (%d)\n", ret); |
84b36ce5 JC |
692 | goto error_run_postdisable; |
693 | } | |
694 | } | |
9572588c | 695 | /* Definitely possible for devices to support both of these. */ |
f4f4673b | 696 | if ((indio_dev->modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) { |
84b36ce5 JC |
697 | indio_dev->currentmode = INDIO_BUFFER_TRIGGERED; |
698 | } else if (indio_dev->modes & INDIO_BUFFER_HARDWARE) { | |
699 | indio_dev->currentmode = INDIO_BUFFER_HARDWARE; | |
03af03ad KW |
700 | } else if (indio_dev->modes & INDIO_BUFFER_SOFTWARE) { |
701 | indio_dev->currentmode = INDIO_BUFFER_SOFTWARE; | |
9572588c | 702 | } else { /* Should never be reached */ |
f4f4673b OP |
703 | /* Can only occur on first buffer */ |
704 | if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) | |
705 | pr_info("Buffer not started: no trigger\n"); | |
84b36ce5 JC |
706 | ret = -EINVAL; |
707 | goto error_run_postdisable; | |
708 | } | |
709 | ||
710 | if (indio_dev->setup_ops->postenable) { | |
711 | ret = indio_dev->setup_ops->postenable(indio_dev); | |
712 | if (ret) { | |
713 | printk(KERN_INFO | |
bec1889d | 714 | "Buffer not started: postenable failed (%d)\n", ret); |
84b36ce5 JC |
715 | indio_dev->currentmode = INDIO_DIRECT_MODE; |
716 | if (indio_dev->setup_ops->postdisable) | |
717 | indio_dev->setup_ops->postdisable(indio_dev); | |
718 | goto error_disable_all_buffers; | |
719 | } | |
720 | } | |
721 | ||
722 | if (indio_dev->available_scan_masks) | |
723 | kfree(compound_mask); | |
724 | else | |
725 | kfree(old_mask); | |
726 | ||
727 | return success; | |
728 | ||
729 | error_disable_all_buffers: | |
730 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
731 | error_run_postdisable: | |
732 | if (indio_dev->setup_ops->postdisable) | |
733 | indio_dev->setup_ops->postdisable(indio_dev); | |
734 | error_remove_inserted: | |
84b36ce5 | 735 | if (insert_buffer) |
9e69c935 | 736 | iio_buffer_deactivate(insert_buffer); |
84b36ce5 JC |
737 | indio_dev->active_scan_mask = old_mask; |
738 | kfree(compound_mask); | |
84b36ce5 JC |
739 | return ret; |
740 | } | |
a9519456 LPC |
741 | |
742 | int iio_update_buffers(struct iio_dev *indio_dev, | |
743 | struct iio_buffer *insert_buffer, | |
744 | struct iio_buffer *remove_buffer) | |
745 | { | |
746 | int ret; | |
747 | ||
3909fab5 LPC |
748 | if (insert_buffer == remove_buffer) |
749 | return 0; | |
750 | ||
a9519456 LPC |
751 | mutex_lock(&indio_dev->info_exist_lock); |
752 | mutex_lock(&indio_dev->mlock); | |
753 | ||
3909fab5 LPC |
754 | if (insert_buffer && iio_buffer_is_active(insert_buffer)) |
755 | insert_buffer = NULL; | |
756 | ||
757 | if (remove_buffer && !iio_buffer_is_active(remove_buffer)) | |
758 | remove_buffer = NULL; | |
759 | ||
760 | if (!insert_buffer && !remove_buffer) { | |
761 | ret = 0; | |
762 | goto out_unlock; | |
763 | } | |
764 | ||
a9519456 LPC |
765 | if (indio_dev->info == NULL) { |
766 | ret = -ENODEV; | |
767 | goto out_unlock; | |
768 | } | |
769 | ||
770 | ret = __iio_update_buffers(indio_dev, insert_buffer, remove_buffer); | |
771 | ||
772 | out_unlock: | |
773 | mutex_unlock(&indio_dev->mlock); | |
774 | mutex_unlock(&indio_dev->info_exist_lock); | |
775 | ||
776 | return ret; | |
777 | } | |
84b36ce5 JC |
778 | EXPORT_SYMBOL_GPL(iio_update_buffers); |
779 | ||
08e7e0ad LPC |
780 | static ssize_t iio_buffer_store_enable(struct device *dev, |
781 | struct device_attribute *attr, | |
782 | const char *buf, | |
783 | size_t len) | |
84b36ce5 JC |
784 | { |
785 | int ret; | |
786 | bool requested_state; | |
787 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
84b36ce5 JC |
788 | bool inlist; |
789 | ||
790 | ret = strtobool(buf, &requested_state); | |
791 | if (ret < 0) | |
792 | return ret; | |
793 | ||
794 | mutex_lock(&indio_dev->mlock); | |
795 | ||
796 | /* Find out if it is in the list */ | |
705ee2c9 | 797 | inlist = iio_buffer_is_active(indio_dev->buffer); |
84b36ce5 JC |
798 | /* Already in desired state */ |
799 | if (inlist == requested_state) | |
800 | goto done; | |
801 | ||
802 | if (requested_state) | |
a9519456 | 803 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
804 | indio_dev->buffer, NULL); |
805 | else | |
a9519456 | 806 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
807 | NULL, indio_dev->buffer); |
808 | ||
809 | if (ret < 0) | |
810 | goto done; | |
811 | done: | |
812 | mutex_unlock(&indio_dev->mlock); | |
813 | return (ret < 0) ? ret : len; | |
814 | } | |
84b36ce5 | 815 | |
d967cb6b LPC |
816 | static const char * const iio_scan_elements_group_name = "scan_elements"; |
817 | ||
37d34556 JC |
818 | static ssize_t iio_buffer_show_watermark(struct device *dev, |
819 | struct device_attribute *attr, | |
820 | char *buf) | |
821 | { | |
822 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
823 | struct iio_buffer *buffer = indio_dev->buffer; | |
824 | ||
825 | return sprintf(buf, "%u\n", buffer->watermark); | |
826 | } | |
827 | ||
828 | static ssize_t iio_buffer_store_watermark(struct device *dev, | |
829 | struct device_attribute *attr, | |
830 | const char *buf, | |
831 | size_t len) | |
832 | { | |
833 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
834 | struct iio_buffer *buffer = indio_dev->buffer; | |
835 | unsigned int val; | |
836 | int ret; | |
837 | ||
838 | ret = kstrtouint(buf, 10, &val); | |
839 | if (ret) | |
840 | return ret; | |
841 | if (!val) | |
842 | return -EINVAL; | |
843 | ||
844 | mutex_lock(&indio_dev->mlock); | |
845 | ||
846 | if (val > buffer->length) { | |
847 | ret = -EINVAL; | |
848 | goto out; | |
849 | } | |
850 | ||
851 | if (iio_buffer_is_active(indio_dev->buffer)) { | |
852 | ret = -EBUSY; | |
853 | goto out; | |
854 | } | |
855 | ||
856 | buffer->watermark = val; | |
f4f4673b OP |
857 | |
858 | if (indio_dev->info->hwfifo_set_watermark) | |
859 | indio_dev->info->hwfifo_set_watermark(indio_dev, val); | |
37d34556 JC |
860 | out: |
861 | mutex_unlock(&indio_dev->mlock); | |
862 | ||
863 | return ret ? ret : len; | |
864 | } | |
865 | ||
08e7e0ad LPC |
866 | static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length, |
867 | iio_buffer_write_length); | |
8d92db28 LPC |
868 | static struct device_attribute dev_attr_length_ro = __ATTR(length, |
869 | S_IRUGO, iio_buffer_read_length, NULL); | |
08e7e0ad LPC |
870 | static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, |
871 | iio_buffer_show_enable, iio_buffer_store_enable); | |
37d34556 JC |
872 | static DEVICE_ATTR(watermark, S_IRUGO | S_IWUSR, |
873 | iio_buffer_show_watermark, iio_buffer_store_watermark); | |
08e7e0ad | 874 | |
6da9b382 OP |
875 | static struct attribute *iio_buffer_attrs[] = { |
876 | &dev_attr_length.attr, | |
877 | &dev_attr_enable.attr, | |
37d34556 | 878 | &dev_attr_watermark.attr, |
6da9b382 OP |
879 | }; |
880 | ||
d967cb6b LPC |
881 | int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev) |
882 | { | |
883 | struct iio_dev_attr *p; | |
884 | struct attribute **attr; | |
885 | struct iio_buffer *buffer = indio_dev->buffer; | |
886 | int ret, i, attrn, attrcount, attrcount_orig = 0; | |
887 | const struct iio_chan_spec *channels; | |
888 | ||
889 | if (!buffer) | |
890 | return 0; | |
891 | ||
08e7e0ad LPC |
892 | attrcount = 0; |
893 | if (buffer->attrs) { | |
894 | while (buffer->attrs[attrcount] != NULL) | |
895 | attrcount++; | |
896 | } | |
897 | ||
6da9b382 OP |
898 | attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, |
899 | sizeof(struct attribute *), GFP_KERNEL); | |
900 | if (!attr) | |
08e7e0ad LPC |
901 | return -ENOMEM; |
902 | ||
6da9b382 OP |
903 | memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); |
904 | if (!buffer->access->set_length) | |
905 | attr[0] = &dev_attr_length_ro.attr; | |
906 | ||
08e7e0ad | 907 | if (buffer->attrs) |
6da9b382 OP |
908 | memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, |
909 | sizeof(struct attribute *) * attrcount); | |
910 | ||
911 | attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; | |
912 | ||
913 | buffer->buffer_group.name = "buffer"; | |
914 | buffer->buffer_group.attrs = attr; | |
08e7e0ad LPC |
915 | |
916 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->buffer_group; | |
917 | ||
d967cb6b LPC |
918 | if (buffer->scan_el_attrs != NULL) { |
919 | attr = buffer->scan_el_attrs->attrs; | |
920 | while (*attr++ != NULL) | |
921 | attrcount_orig++; | |
922 | } | |
923 | attrcount = attrcount_orig; | |
924 | INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); | |
925 | channels = indio_dev->channels; | |
926 | if (channels) { | |
927 | /* new magic */ | |
928 | for (i = 0; i < indio_dev->num_channels; i++) { | |
929 | if (channels[i].scan_index < 0) | |
930 | continue; | |
931 | ||
932 | /* Establish necessary mask length */ | |
933 | if (channels[i].scan_index > | |
934 | (int)indio_dev->masklength - 1) | |
935 | indio_dev->masklength | |
936 | = channels[i].scan_index + 1; | |
937 | ||
938 | ret = iio_buffer_add_channel_sysfs(indio_dev, | |
939 | &channels[i]); | |
940 | if (ret < 0) | |
941 | goto error_cleanup_dynamic; | |
942 | attrcount += ret; | |
943 | if (channels[i].type == IIO_TIMESTAMP) | |
944 | indio_dev->scan_index_timestamp = | |
945 | channels[i].scan_index; | |
946 | } | |
947 | if (indio_dev->masklength && buffer->scan_mask == NULL) { | |
948 | buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), | |
949 | sizeof(*buffer->scan_mask), | |
950 | GFP_KERNEL); | |
951 | if (buffer->scan_mask == NULL) { | |
952 | ret = -ENOMEM; | |
953 | goto error_cleanup_dynamic; | |
954 | } | |
955 | } | |
956 | } | |
957 | ||
958 | buffer->scan_el_group.name = iio_scan_elements_group_name; | |
959 | ||
960 | buffer->scan_el_group.attrs = kcalloc(attrcount + 1, | |
961 | sizeof(buffer->scan_el_group.attrs[0]), | |
962 | GFP_KERNEL); | |
963 | if (buffer->scan_el_group.attrs == NULL) { | |
964 | ret = -ENOMEM; | |
965 | goto error_free_scan_mask; | |
966 | } | |
967 | if (buffer->scan_el_attrs) | |
968 | memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs, | |
969 | sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig); | |
970 | attrn = attrcount_orig; | |
971 | ||
972 | list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l) | |
973 | buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr; | |
974 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group; | |
975 | ||
976 | return 0; | |
977 | ||
978 | error_free_scan_mask: | |
979 | kfree(buffer->scan_mask); | |
980 | error_cleanup_dynamic: | |
981 | iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); | |
08e7e0ad | 982 | kfree(indio_dev->buffer->buffer_group.attrs); |
d967cb6b LPC |
983 | |
984 | return ret; | |
985 | } | |
986 | ||
987 | void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev) | |
988 | { | |
989 | if (!indio_dev->buffer) | |
990 | return; | |
991 | ||
992 | kfree(indio_dev->buffer->scan_mask); | |
08e7e0ad | 993 | kfree(indio_dev->buffer->buffer_group.attrs); |
d967cb6b LPC |
994 | kfree(indio_dev->buffer->scan_el_group.attrs); |
995 | iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list); | |
996 | } | |
997 | ||
81636632 LPC |
998 | /** |
999 | * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected | |
1000 | * @indio_dev: the iio device | |
1001 | * @mask: scan mask to be checked | |
1002 | * | |
1003 | * Return true if exactly one bit is set in the scan mask, false otherwise. It | |
1004 | * can be used for devices where only one channel can be active for sampling at | |
1005 | * a time. | |
1006 | */ | |
1007 | bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, | |
1008 | const unsigned long *mask) | |
1009 | { | |
1010 | return bitmap_weight(mask, indio_dev->masklength) == 1; | |
1011 | } | |
1012 | EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot); | |
1013 | ||
f79a9098 JC |
1014 | int iio_scan_mask_query(struct iio_dev *indio_dev, |
1015 | struct iio_buffer *buffer, int bit) | |
32b5eeca | 1016 | { |
f8c6f4e9 | 1017 | if (bit > indio_dev->masklength) |
32b5eeca JC |
1018 | return -EINVAL; |
1019 | ||
14555b14 | 1020 | if (!buffer->scan_mask) |
32b5eeca | 1021 | return 0; |
32b5eeca | 1022 | |
2076a20f AB |
1023 | /* Ensure return value is 0 or 1. */ |
1024 | return !!test_bit(bit, buffer->scan_mask); | |
32b5eeca JC |
1025 | }; |
1026 | EXPORT_SYMBOL_GPL(iio_scan_mask_query); | |
5ada4ea9 JC |
1027 | |
1028 | /** | |
1029 | * struct iio_demux_table() - table describing demux memcpy ops | |
1030 | * @from: index to copy from | |
99698b45 | 1031 | * @to: index to copy to |
5ada4ea9 JC |
1032 | * @length: how many bytes to copy |
1033 | * @l: list head used for management | |
1034 | */ | |
1035 | struct iio_demux_table { | |
1036 | unsigned from; | |
1037 | unsigned to; | |
1038 | unsigned length; | |
1039 | struct list_head l; | |
1040 | }; | |
1041 | ||
5d65d920 LPC |
1042 | static const void *iio_demux(struct iio_buffer *buffer, |
1043 | const void *datain) | |
5ada4ea9 JC |
1044 | { |
1045 | struct iio_demux_table *t; | |
1046 | ||
1047 | if (list_empty(&buffer->demux_list)) | |
1048 | return datain; | |
1049 | list_for_each_entry(t, &buffer->demux_list, l) | |
1050 | memcpy(buffer->demux_bounce + t->to, | |
1051 | datain + t->from, t->length); | |
1052 | ||
1053 | return buffer->demux_bounce; | |
1054 | } | |
1055 | ||
5d65d920 | 1056 | static int iio_push_to_buffer(struct iio_buffer *buffer, const void *data) |
5ada4ea9 | 1057 | { |
5d65d920 | 1058 | const void *dataout = iio_demux(buffer, data); |
37d34556 JC |
1059 | int ret; |
1060 | ||
1061 | ret = buffer->access->store_to(buffer, dataout); | |
1062 | if (ret) | |
1063 | return ret; | |
5ada4ea9 | 1064 | |
37d34556 JC |
1065 | /* |
1066 | * We can't just test for watermark to decide if we wake the poll queue | |
1067 | * because read may request less samples than the watermark. | |
1068 | */ | |
1069 | wake_up_interruptible_poll(&buffer->pollq, POLLIN | POLLRDNORM); | |
1070 | return 0; | |
5ada4ea9 | 1071 | } |
5ada4ea9 | 1072 | |
842cd100 JC |
1073 | static void iio_buffer_demux_free(struct iio_buffer *buffer) |
1074 | { | |
1075 | struct iio_demux_table *p, *q; | |
1076 | list_for_each_entry_safe(p, q, &buffer->demux_list, l) { | |
1077 | list_del(&p->l); | |
1078 | kfree(p); | |
1079 | } | |
1080 | } | |
1081 | ||
84b36ce5 | 1082 | |
5d65d920 | 1083 | int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data) |
84b36ce5 JC |
1084 | { |
1085 | int ret; | |
1086 | struct iio_buffer *buf; | |
1087 | ||
1088 | list_for_each_entry(buf, &indio_dev->buffer_list, buffer_list) { | |
1089 | ret = iio_push_to_buffer(buf, data); | |
1090 | if (ret < 0) | |
1091 | return ret; | |
1092 | } | |
1093 | ||
1094 | return 0; | |
1095 | } | |
1096 | EXPORT_SYMBOL_GPL(iio_push_to_buffers); | |
1097 | ||
cbe88bcc LPC |
1098 | static int iio_buffer_add_demux(struct iio_buffer *buffer, |
1099 | struct iio_demux_table **p, unsigned int in_loc, unsigned int out_loc, | |
1100 | unsigned int length) | |
1101 | { | |
1102 | ||
1103 | if (*p && (*p)->from + (*p)->length == in_loc && | |
1104 | (*p)->to + (*p)->length == out_loc) { | |
1105 | (*p)->length += length; | |
1106 | } else { | |
7cdca178 | 1107 | *p = kmalloc(sizeof(**p), GFP_KERNEL); |
cbe88bcc LPC |
1108 | if (*p == NULL) |
1109 | return -ENOMEM; | |
1110 | (*p)->from = in_loc; | |
1111 | (*p)->to = out_loc; | |
1112 | (*p)->length = length; | |
1113 | list_add_tail(&(*p)->l, &buffer->demux_list); | |
1114 | } | |
1115 | ||
1116 | return 0; | |
1117 | } | |
1118 | ||
84b36ce5 JC |
1119 | static int iio_buffer_update_demux(struct iio_dev *indio_dev, |
1120 | struct iio_buffer *buffer) | |
5ada4ea9 JC |
1121 | { |
1122 | const struct iio_chan_spec *ch; | |
5ada4ea9 JC |
1123 | int ret, in_ind = -1, out_ind, length; |
1124 | unsigned in_loc = 0, out_loc = 0; | |
cbe88bcc | 1125 | struct iio_demux_table *p = NULL; |
5ada4ea9 JC |
1126 | |
1127 | /* Clear out any old demux */ | |
842cd100 | 1128 | iio_buffer_demux_free(buffer); |
5ada4ea9 JC |
1129 | kfree(buffer->demux_bounce); |
1130 | buffer->demux_bounce = NULL; | |
1131 | ||
1132 | /* First work out which scan mode we will actually have */ | |
1133 | if (bitmap_equal(indio_dev->active_scan_mask, | |
1134 | buffer->scan_mask, | |
1135 | indio_dev->masklength)) | |
1136 | return 0; | |
1137 | ||
1138 | /* Now we have the two masks, work from least sig and build up sizes */ | |
1139 | for_each_set_bit(out_ind, | |
61bd55ce | 1140 | buffer->scan_mask, |
5ada4ea9 JC |
1141 | indio_dev->masklength) { |
1142 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
1143 | indio_dev->masklength, | |
1144 | in_ind + 1); | |
1145 | while (in_ind != out_ind) { | |
1146 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
1147 | indio_dev->masklength, | |
1148 | in_ind + 1); | |
1149 | ch = iio_find_channel_from_si(indio_dev, in_ind); | |
0ee8546a SP |
1150 | if (ch->scan_type.repeat > 1) |
1151 | length = ch->scan_type.storagebits / 8 * | |
1152 | ch->scan_type.repeat; | |
1153 | else | |
1154 | length = ch->scan_type.storagebits / 8; | |
5ada4ea9 | 1155 | /* Make sure we are aligned */ |
61072dbc | 1156 | in_loc = roundup(in_loc, length) + length; |
5ada4ea9 JC |
1157 | } |
1158 | ch = iio_find_channel_from_si(indio_dev, in_ind); | |
0ee8546a SP |
1159 | if (ch->scan_type.repeat > 1) |
1160 | length = ch->scan_type.storagebits / 8 * | |
1161 | ch->scan_type.repeat; | |
1162 | else | |
1163 | length = ch->scan_type.storagebits / 8; | |
61072dbc LPC |
1164 | out_loc = roundup(out_loc, length); |
1165 | in_loc = roundup(in_loc, length); | |
cbe88bcc LPC |
1166 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); |
1167 | if (ret) | |
1168 | goto error_clear_mux_table; | |
5ada4ea9 JC |
1169 | out_loc += length; |
1170 | in_loc += length; | |
1171 | } | |
1172 | /* Relies on scan_timestamp being last */ | |
1173 | if (buffer->scan_timestamp) { | |
5ada4ea9 | 1174 | ch = iio_find_channel_from_si(indio_dev, |
f1264809 | 1175 | indio_dev->scan_index_timestamp); |
0ee8546a SP |
1176 | if (ch->scan_type.repeat > 1) |
1177 | length = ch->scan_type.storagebits / 8 * | |
1178 | ch->scan_type.repeat; | |
1179 | else | |
1180 | length = ch->scan_type.storagebits / 8; | |
61072dbc LPC |
1181 | out_loc = roundup(out_loc, length); |
1182 | in_loc = roundup(in_loc, length); | |
cbe88bcc LPC |
1183 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); |
1184 | if (ret) | |
1185 | goto error_clear_mux_table; | |
5ada4ea9 JC |
1186 | out_loc += length; |
1187 | in_loc += length; | |
1188 | } | |
1189 | buffer->demux_bounce = kzalloc(out_loc, GFP_KERNEL); | |
1190 | if (buffer->demux_bounce == NULL) { | |
1191 | ret = -ENOMEM; | |
1192 | goto error_clear_mux_table; | |
1193 | } | |
1194 | return 0; | |
1195 | ||
1196 | error_clear_mux_table: | |
842cd100 JC |
1197 | iio_buffer_demux_free(buffer); |
1198 | ||
5ada4ea9 JC |
1199 | return ret; |
1200 | } | |
84b36ce5 JC |
1201 | |
1202 | int iio_update_demux(struct iio_dev *indio_dev) | |
1203 | { | |
1204 | struct iio_buffer *buffer; | |
1205 | int ret; | |
1206 | ||
1207 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
1208 | ret = iio_buffer_update_demux(indio_dev, buffer); | |
1209 | if (ret < 0) | |
1210 | goto error_clear_mux_table; | |
1211 | } | |
1212 | return 0; | |
1213 | ||
1214 | error_clear_mux_table: | |
1215 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) | |
1216 | iio_buffer_demux_free(buffer); | |
1217 | ||
1218 | return ret; | |
1219 | } | |
5ada4ea9 | 1220 | EXPORT_SYMBOL_GPL(iio_update_demux); |
9e69c935 LPC |
1221 | |
1222 | /** | |
1223 | * iio_buffer_release() - Free a buffer's resources | |
1224 | * @ref: Pointer to the kref embedded in the iio_buffer struct | |
1225 | * | |
1226 | * This function is called when the last reference to the buffer has been | |
1227 | * dropped. It will typically free all resources allocated by the buffer. Do not | |
1228 | * call this function manually, always use iio_buffer_put() when done using a | |
1229 | * buffer. | |
1230 | */ | |
1231 | static void iio_buffer_release(struct kref *ref) | |
1232 | { | |
1233 | struct iio_buffer *buffer = container_of(ref, struct iio_buffer, ref); | |
1234 | ||
1235 | buffer->access->release(buffer); | |
1236 | } | |
1237 | ||
1238 | /** | |
1239 | * iio_buffer_get() - Grab a reference to the buffer | |
1240 | * @buffer: The buffer to grab a reference for, may be NULL | |
1241 | * | |
1242 | * Returns the pointer to the buffer that was passed into the function. | |
1243 | */ | |
1244 | struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer) | |
1245 | { | |
1246 | if (buffer) | |
1247 | kref_get(&buffer->ref); | |
1248 | ||
1249 | return buffer; | |
1250 | } | |
1251 | EXPORT_SYMBOL_GPL(iio_buffer_get); | |
1252 | ||
1253 | /** | |
1254 | * iio_buffer_put() - Release the reference to the buffer | |
1255 | * @buffer: The buffer to release the reference for, may be NULL | |
1256 | */ | |
1257 | void iio_buffer_put(struct iio_buffer *buffer) | |
1258 | { | |
1259 | if (buffer) | |
1260 | kref_put(&buffer->ref, iio_buffer_release); | |
1261 | } | |
1262 | EXPORT_SYMBOL_GPL(iio_buffer_put); |