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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 */ | |
c6f67a1f OP |
74 | if (!to_wait && avail < to_flush) |
75 | iio_buffer_flush_hwfifo(indio_dev, buf, | |
76 | to_flush - avail); | |
f4f4673b OP |
77 | return true; |
78 | } | |
79 | ||
80 | if (to_flush) | |
81 | flushed = iio_buffer_flush_hwfifo(indio_dev, buf, | |
82 | to_wait - avail); | |
83 | if (flushed <= 0) | |
84 | return false; | |
85 | ||
86 | if (avail + flushed >= to_wait) | |
37d34556 JC |
87 | return true; |
88 | ||
89 | return false; | |
90 | } | |
91 | ||
7026ea4b | 92 | /** |
14555b14 | 93 | * iio_buffer_read_first_n_outer() - chrdev read for buffer access |
0123635a CO |
94 | * @filp: File structure pointer for the char device |
95 | * @buf: Destination buffer for iio buffer read | |
96 | * @n: First n bytes to read | |
97 | * @f_ps: Long offset provided by the user as a seek position | |
7026ea4b | 98 | * |
14555b14 JC |
99 | * This function relies on all buffer implementations having an |
100 | * iio_buffer as their first element. | |
0123635a CO |
101 | * |
102 | * Return: negative values corresponding to error codes or ret != 0 | |
103 | * for ending the reading activity | |
7026ea4b | 104 | **/ |
14555b14 JC |
105 | ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf, |
106 | size_t n, loff_t *f_ps) | |
7026ea4b | 107 | { |
1aa04278 | 108 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 109 | struct iio_buffer *rb = indio_dev->buffer; |
fcf68f3c | 110 | DEFINE_WAIT_FUNC(wait, woken_wake_function); |
37d34556 | 111 | size_t datum_size; |
c6f67a1f | 112 | size_t to_wait; |
5dba4b14 | 113 | int ret = 0; |
d5857d65 | 114 | |
f18e7a06 LPC |
115 | if (!indio_dev->info) |
116 | return -ENODEV; | |
117 | ||
96e00f11 | 118 | if (!rb || !rb->access->read_first_n) |
7026ea4b | 119 | return -EINVAL; |
ee551a10 | 120 | |
37d34556 JC |
121 | datum_size = rb->bytes_per_datum; |
122 | ||
123 | /* | |
124 | * If datum_size is 0 there will never be anything to read from the | |
125 | * buffer, so signal end of file now. | |
126 | */ | |
127 | if (!datum_size) | |
128 | return 0; | |
129 | ||
c6f67a1f OP |
130 | if (filp->f_flags & O_NONBLOCK) |
131 | to_wait = 0; | |
132 | else | |
133 | to_wait = min_t(size_t, n / datum_size, rb->watermark); | |
37d34556 | 134 | |
fcf68f3c | 135 | add_wait_queue(&rb->pollq, &wait); |
ee551a10 | 136 | do { |
fcf68f3c BN |
137 | if (!indio_dev->info) { |
138 | ret = -ENODEV; | |
139 | break; | |
140 | } | |
141 | ||
142 | if (!iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size)) { | |
143 | if (signal_pending(current)) { | |
144 | ret = -ERESTARTSYS; | |
145 | break; | |
146 | } | |
147 | ||
148 | wait_woken(&wait, TASK_INTERRUPTIBLE, | |
149 | MAX_SCHEDULE_TIMEOUT); | |
150 | continue; | |
151 | } | |
ee551a10 LPC |
152 | |
153 | ret = rb->access->read_first_n(rb, n, buf); | |
154 | if (ret == 0 && (filp->f_flags & O_NONBLOCK)) | |
155 | ret = -EAGAIN; | |
5dba4b14 | 156 | } while (ret == 0); |
fcf68f3c | 157 | remove_wait_queue(&rb->pollq, &wait); |
ee551a10 LPC |
158 | |
159 | return ret; | |
7026ea4b JC |
160 | } |
161 | ||
a7348347 | 162 | /** |
14555b14 | 163 | * iio_buffer_poll() - poll the buffer to find out if it has data |
0123635a CO |
164 | * @filp: File structure pointer for device access |
165 | * @wait: Poll table structure pointer for which the driver adds | |
166 | * a wait queue | |
167 | * | |
168 | * Return: (POLLIN | POLLRDNORM) if data is available for reading | |
169 | * or 0 for other cases | |
a7348347 | 170 | */ |
14555b14 JC |
171 | unsigned int iio_buffer_poll(struct file *filp, |
172 | struct poll_table_struct *wait) | |
a7348347 | 173 | { |
1aa04278 | 174 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 175 | struct iio_buffer *rb = indio_dev->buffer; |
a7348347 | 176 | |
f18e7a06 | 177 | if (!indio_dev->info) |
1bdc0293 | 178 | return 0; |
f18e7a06 | 179 | |
a7348347 | 180 | poll_wait(filp, &rb->pollq, wait); |
f4f4673b | 181 | if (iio_buffer_ready(indio_dev, rb, rb->watermark, 0)) |
a7348347 | 182 | return POLLIN | POLLRDNORM; |
8d213f24 | 183 | return 0; |
a7348347 JC |
184 | } |
185 | ||
d2f0a48f LPC |
186 | /** |
187 | * iio_buffer_wakeup_poll - Wakes up the buffer waitqueue | |
188 | * @indio_dev: The IIO device | |
189 | * | |
190 | * Wakes up the event waitqueue used for poll(). Should usually | |
191 | * be called when the device is unregistered. | |
192 | */ | |
193 | void iio_buffer_wakeup_poll(struct iio_dev *indio_dev) | |
194 | { | |
195 | if (!indio_dev->buffer) | |
196 | return; | |
197 | ||
198 | wake_up(&indio_dev->buffer->pollq); | |
199 | } | |
200 | ||
f79a9098 | 201 | void iio_buffer_init(struct iio_buffer *buffer) |
7026ea4b | 202 | { |
5ada4ea9 | 203 | INIT_LIST_HEAD(&buffer->demux_list); |
705ee2c9 | 204 | INIT_LIST_HEAD(&buffer->buffer_list); |
14555b14 | 205 | init_waitqueue_head(&buffer->pollq); |
9e69c935 | 206 | kref_init(&buffer->ref); |
4a605357 LPC |
207 | if (!buffer->watermark) |
208 | buffer->watermark = 1; | |
7026ea4b | 209 | } |
14555b14 | 210 | EXPORT_SYMBOL(iio_buffer_init); |
7026ea4b | 211 | |
1d892719 | 212 | static ssize_t iio_show_scan_index(struct device *dev, |
8d213f24 JC |
213 | struct device_attribute *attr, |
214 | char *buf) | |
1d892719 | 215 | { |
8d213f24 | 216 | return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index); |
1d892719 JC |
217 | } |
218 | ||
219 | static ssize_t iio_show_fixed_type(struct device *dev, | |
220 | struct device_attribute *attr, | |
221 | char *buf) | |
222 | { | |
223 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); | |
8310b86c JC |
224 | u8 type = this_attr->c->scan_type.endianness; |
225 | ||
226 | if (type == IIO_CPU) { | |
9d5d1153 JC |
227 | #ifdef __LITTLE_ENDIAN |
228 | type = IIO_LE; | |
229 | #else | |
230 | type = IIO_BE; | |
231 | #endif | |
8310b86c | 232 | } |
0ee8546a SP |
233 | if (this_attr->c->scan_type.repeat > 1) |
234 | return sprintf(buf, "%s:%c%d/%dX%d>>%u\n", | |
235 | iio_endian_prefix[type], | |
236 | this_attr->c->scan_type.sign, | |
237 | this_attr->c->scan_type.realbits, | |
238 | this_attr->c->scan_type.storagebits, | |
239 | this_attr->c->scan_type.repeat, | |
240 | this_attr->c->scan_type.shift); | |
241 | else | |
242 | return sprintf(buf, "%s:%c%d/%d>>%u\n", | |
8310b86c | 243 | iio_endian_prefix[type], |
1d892719 JC |
244 | this_attr->c->scan_type.sign, |
245 | this_attr->c->scan_type.realbits, | |
246 | this_attr->c->scan_type.storagebits, | |
247 | this_attr->c->scan_type.shift); | |
248 | } | |
249 | ||
8d213f24 JC |
250 | static ssize_t iio_scan_el_show(struct device *dev, |
251 | struct device_attribute *attr, | |
252 | char *buf) | |
253 | { | |
254 | int ret; | |
e53f5ac5 | 255 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 256 | |
2076a20f AB |
257 | /* Ensure ret is 0 or 1. */ |
258 | ret = !!test_bit(to_iio_dev_attr(attr)->address, | |
5ada4ea9 JC |
259 | indio_dev->buffer->scan_mask); |
260 | ||
8d213f24 JC |
261 | return sprintf(buf, "%d\n", ret); |
262 | } | |
263 | ||
217a5cf0 LPC |
264 | /* Note NULL used as error indicator as it doesn't make sense. */ |
265 | static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks, | |
266 | unsigned int masklength, | |
1e1ec286 LPC |
267 | const unsigned long *mask, |
268 | bool strict) | |
217a5cf0 LPC |
269 | { |
270 | if (bitmap_empty(mask, masklength)) | |
271 | return NULL; | |
272 | while (*av_masks) { | |
1e1ec286 LPC |
273 | if (strict) { |
274 | if (bitmap_equal(mask, av_masks, masklength)) | |
275 | return av_masks; | |
276 | } else { | |
277 | if (bitmap_subset(mask, av_masks, masklength)) | |
278 | return av_masks; | |
279 | } | |
217a5cf0 LPC |
280 | av_masks += BITS_TO_LONGS(masklength); |
281 | } | |
282 | return NULL; | |
283 | } | |
284 | ||
285 | static bool iio_validate_scan_mask(struct iio_dev *indio_dev, | |
286 | const unsigned long *mask) | |
287 | { | |
288 | if (!indio_dev->setup_ops->validate_scan_mask) | |
289 | return true; | |
290 | ||
291 | return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask); | |
292 | } | |
293 | ||
294 | /** | |
295 | * iio_scan_mask_set() - set particular bit in the scan mask | |
296 | * @indio_dev: the iio device | |
297 | * @buffer: the buffer whose scan mask we are interested in | |
298 | * @bit: the bit to be set. | |
299 | * | |
300 | * Note that at this point we have no way of knowing what other | |
301 | * buffers might request, hence this code only verifies that the | |
302 | * individual buffers request is plausible. | |
303 | */ | |
304 | static int iio_scan_mask_set(struct iio_dev *indio_dev, | |
305 | struct iio_buffer *buffer, int bit) | |
306 | { | |
307 | const unsigned long *mask; | |
308 | unsigned long *trialmask; | |
309 | ||
057ac1ac ME |
310 | trialmask = kmalloc_array(BITS_TO_LONGS(indio_dev->masklength), |
311 | sizeof(*trialmask), | |
312 | GFP_KERNEL); | |
217a5cf0 LPC |
313 | if (trialmask == NULL) |
314 | return -ENOMEM; | |
315 | if (!indio_dev->masklength) { | |
231bfe53 | 316 | WARN(1, "Trying to set scanmask prior to registering buffer\n"); |
217a5cf0 LPC |
317 | goto err_invalid_mask; |
318 | } | |
319 | bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength); | |
320 | set_bit(bit, trialmask); | |
321 | ||
322 | if (!iio_validate_scan_mask(indio_dev, trialmask)) | |
323 | goto err_invalid_mask; | |
324 | ||
325 | if (indio_dev->available_scan_masks) { | |
326 | mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
327 | indio_dev->masklength, | |
1e1ec286 | 328 | trialmask, false); |
217a5cf0 LPC |
329 | if (!mask) |
330 | goto err_invalid_mask; | |
331 | } | |
332 | bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength); | |
333 | ||
334 | kfree(trialmask); | |
335 | ||
336 | return 0; | |
337 | ||
338 | err_invalid_mask: | |
339 | kfree(trialmask); | |
340 | return -EINVAL; | |
341 | } | |
342 | ||
14555b14 | 343 | static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit) |
8d213f24 | 344 | { |
14555b14 | 345 | clear_bit(bit, buffer->scan_mask); |
8d213f24 JC |
346 | return 0; |
347 | } | |
348 | ||
349 | static ssize_t iio_scan_el_store(struct device *dev, | |
350 | struct device_attribute *attr, | |
351 | const char *buf, | |
352 | size_t len) | |
353 | { | |
a714af27 | 354 | int ret; |
8d213f24 | 355 | bool state; |
e53f5ac5 | 356 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 357 | struct iio_buffer *buffer = indio_dev->buffer; |
8d213f24 JC |
358 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
359 | ||
a714af27 JC |
360 | ret = strtobool(buf, &state); |
361 | if (ret < 0) | |
362 | return ret; | |
8d213f24 | 363 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 364 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
365 | ret = -EBUSY; |
366 | goto error_ret; | |
367 | } | |
f79a9098 | 368 | ret = iio_scan_mask_query(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
369 | if (ret < 0) |
370 | goto error_ret; | |
371 | if (!state && ret) { | |
14555b14 | 372 | ret = iio_scan_mask_clear(buffer, this_attr->address); |
8d213f24 JC |
373 | if (ret) |
374 | goto error_ret; | |
375 | } else if (state && !ret) { | |
f79a9098 | 376 | ret = iio_scan_mask_set(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
377 | if (ret) |
378 | goto error_ret; | |
379 | } | |
380 | ||
381 | error_ret: | |
382 | mutex_unlock(&indio_dev->mlock); | |
383 | ||
5a2a6e11 | 384 | return ret < 0 ? ret : len; |
8d213f24 JC |
385 | |
386 | } | |
387 | ||
388 | static ssize_t iio_scan_el_ts_show(struct device *dev, | |
389 | struct device_attribute *attr, | |
390 | char *buf) | |
391 | { | |
e53f5ac5 | 392 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
f8c6f4e9 | 393 | return sprintf(buf, "%d\n", indio_dev->buffer->scan_timestamp); |
8d213f24 JC |
394 | } |
395 | ||
396 | static ssize_t iio_scan_el_ts_store(struct device *dev, | |
397 | struct device_attribute *attr, | |
398 | const char *buf, | |
399 | size_t len) | |
400 | { | |
a714af27 | 401 | int ret; |
e53f5ac5 | 402 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 403 | bool state; |
1aa04278 | 404 | |
a714af27 JC |
405 | ret = strtobool(buf, &state); |
406 | if (ret < 0) | |
407 | return ret; | |
408 | ||
8d213f24 | 409 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 410 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
411 | ret = -EBUSY; |
412 | goto error_ret; | |
413 | } | |
14555b14 | 414 | indio_dev->buffer->scan_timestamp = state; |
8d213f24 JC |
415 | error_ret: |
416 | mutex_unlock(&indio_dev->mlock); | |
417 | ||
418 | return ret ? ret : len; | |
419 | } | |
420 | ||
14555b14 JC |
421 | static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev, |
422 | const struct iio_chan_spec *chan) | |
1d892719 | 423 | { |
26d25ae3 | 424 | int ret, attrcount = 0; |
14555b14 | 425 | struct iio_buffer *buffer = indio_dev->buffer; |
1d892719 | 426 | |
26d25ae3 | 427 | ret = __iio_add_chan_devattr("index", |
1d892719 JC |
428 | chan, |
429 | &iio_show_scan_index, | |
430 | NULL, | |
431 | 0, | |
3704432f | 432 | IIO_SEPARATE, |
1aa04278 | 433 | &indio_dev->dev, |
14555b14 | 434 | &buffer->scan_el_dev_attr_list); |
1d892719 | 435 | if (ret) |
92825ff9 | 436 | return ret; |
26d25ae3 JC |
437 | attrcount++; |
438 | ret = __iio_add_chan_devattr("type", | |
1d892719 JC |
439 | chan, |
440 | &iio_show_fixed_type, | |
441 | NULL, | |
442 | 0, | |
443 | 0, | |
1aa04278 | 444 | &indio_dev->dev, |
14555b14 | 445 | &buffer->scan_el_dev_attr_list); |
1d892719 | 446 | if (ret) |
92825ff9 | 447 | return ret; |
26d25ae3 | 448 | attrcount++; |
a88b3ebc | 449 | if (chan->type != IIO_TIMESTAMP) |
26d25ae3 | 450 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
451 | chan, |
452 | &iio_scan_el_show, | |
453 | &iio_scan_el_store, | |
454 | chan->scan_index, | |
455 | 0, | |
1aa04278 | 456 | &indio_dev->dev, |
14555b14 | 457 | &buffer->scan_el_dev_attr_list); |
a88b3ebc | 458 | else |
26d25ae3 | 459 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
460 | chan, |
461 | &iio_scan_el_ts_show, | |
462 | &iio_scan_el_ts_store, | |
463 | chan->scan_index, | |
464 | 0, | |
1aa04278 | 465 | &indio_dev->dev, |
14555b14 | 466 | &buffer->scan_el_dev_attr_list); |
9572588c | 467 | if (ret) |
92825ff9 | 468 | return ret; |
26d25ae3 JC |
469 | attrcount++; |
470 | ret = attrcount; | |
1d892719 JC |
471 | return ret; |
472 | } | |
473 | ||
08e7e0ad LPC |
474 | static ssize_t iio_buffer_read_length(struct device *dev, |
475 | struct device_attribute *attr, | |
476 | char *buf) | |
7026ea4b | 477 | { |
e53f5ac5 | 478 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 479 | struct iio_buffer *buffer = indio_dev->buffer; |
7026ea4b | 480 | |
37495660 | 481 | return sprintf(buf, "%d\n", buffer->length); |
7026ea4b | 482 | } |
7026ea4b | 483 | |
08e7e0ad LPC |
484 | static ssize_t iio_buffer_write_length(struct device *dev, |
485 | struct device_attribute *attr, | |
486 | const char *buf, size_t len) | |
7026ea4b | 487 | { |
e53f5ac5 | 488 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 489 | struct iio_buffer *buffer = indio_dev->buffer; |
948ad205 LPC |
490 | unsigned int val; |
491 | int ret; | |
8d213f24 | 492 | |
948ad205 | 493 | ret = kstrtouint(buf, 10, &val); |
7026ea4b JC |
494 | if (ret) |
495 | return ret; | |
496 | ||
37495660 LPC |
497 | if (val == buffer->length) |
498 | return len; | |
7026ea4b | 499 | |
e38c79e0 | 500 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 501 | if (iio_buffer_is_active(indio_dev->buffer)) { |
e38c79e0 LPC |
502 | ret = -EBUSY; |
503 | } else { | |
8d92db28 | 504 | buffer->access->set_length(buffer, val); |
e38c79e0 | 505 | ret = 0; |
7026ea4b | 506 | } |
37d34556 JC |
507 | if (ret) |
508 | goto out; | |
509 | if (buffer->length && buffer->length < buffer->watermark) | |
510 | buffer->watermark = buffer->length; | |
511 | out: | |
e38c79e0 | 512 | mutex_unlock(&indio_dev->mlock); |
7026ea4b | 513 | |
e38c79e0 | 514 | return ret ? ret : len; |
7026ea4b | 515 | } |
7026ea4b | 516 | |
08e7e0ad LPC |
517 | static ssize_t iio_buffer_show_enable(struct device *dev, |
518 | struct device_attribute *attr, | |
519 | char *buf) | |
7026ea4b | 520 | { |
e53f5ac5 | 521 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
705ee2c9 | 522 | return sprintf(buf, "%d\n", iio_buffer_is_active(indio_dev->buffer)); |
7026ea4b | 523 | } |
7026ea4b | 524 | |
182b4905 LPC |
525 | static unsigned int iio_storage_bytes_for_si(struct iio_dev *indio_dev, |
526 | unsigned int scan_index) | |
527 | { | |
528 | const struct iio_chan_spec *ch; | |
529 | unsigned int bytes; | |
530 | ||
531 | ch = iio_find_channel_from_si(indio_dev, scan_index); | |
532 | bytes = ch->scan_type.storagebits / 8; | |
533 | if (ch->scan_type.repeat > 1) | |
534 | bytes *= ch->scan_type.repeat; | |
535 | return bytes; | |
536 | } | |
537 | ||
538 | static unsigned int iio_storage_bytes_for_timestamp(struct iio_dev *indio_dev) | |
539 | { | |
540 | return iio_storage_bytes_for_si(indio_dev, | |
541 | indio_dev->scan_index_timestamp); | |
542 | } | |
543 | ||
183f4173 PM |
544 | static int iio_compute_scan_bytes(struct iio_dev *indio_dev, |
545 | const unsigned long *mask, bool timestamp) | |
959d2952 | 546 | { |
959d2952 JC |
547 | unsigned bytes = 0; |
548 | int length, i; | |
959d2952 JC |
549 | |
550 | /* How much space will the demuxed element take? */ | |
6b3b58ed | 551 | for_each_set_bit(i, mask, |
959d2952 | 552 | indio_dev->masklength) { |
182b4905 | 553 | length = iio_storage_bytes_for_si(indio_dev, i); |
959d2952 JC |
554 | bytes = ALIGN(bytes, length); |
555 | bytes += length; | |
556 | } | |
182b4905 | 557 | |
6b3b58ed | 558 | if (timestamp) { |
182b4905 | 559 | length = iio_storage_bytes_for_timestamp(indio_dev); |
959d2952 JC |
560 | bytes = ALIGN(bytes, length); |
561 | bytes += length; | |
562 | } | |
6b3b58ed JC |
563 | return bytes; |
564 | } | |
565 | ||
9e69c935 LPC |
566 | static void iio_buffer_activate(struct iio_dev *indio_dev, |
567 | struct iio_buffer *buffer) | |
568 | { | |
569 | iio_buffer_get(buffer); | |
570 | list_add(&buffer->buffer_list, &indio_dev->buffer_list); | |
571 | } | |
572 | ||
573 | static void iio_buffer_deactivate(struct iio_buffer *buffer) | |
574 | { | |
575 | list_del_init(&buffer->buffer_list); | |
37d34556 | 576 | wake_up_interruptible(&buffer->pollq); |
9e69c935 LPC |
577 | iio_buffer_put(buffer); |
578 | } | |
579 | ||
1250186a LPC |
580 | static void iio_buffer_deactivate_all(struct iio_dev *indio_dev) |
581 | { | |
582 | struct iio_buffer *buffer, *_buffer; | |
583 | ||
584 | list_for_each_entry_safe(buffer, _buffer, | |
585 | &indio_dev->buffer_list, buffer_list) | |
586 | iio_buffer_deactivate(buffer); | |
587 | } | |
588 | ||
e18a2ad4 LPC |
589 | static int iio_buffer_enable(struct iio_buffer *buffer, |
590 | struct iio_dev *indio_dev) | |
591 | { | |
592 | if (!buffer->access->enable) | |
593 | return 0; | |
594 | return buffer->access->enable(buffer, indio_dev); | |
595 | } | |
596 | ||
597 | static int iio_buffer_disable(struct iio_buffer *buffer, | |
598 | struct iio_dev *indio_dev) | |
599 | { | |
600 | if (!buffer->access->disable) | |
601 | return 0; | |
602 | return buffer->access->disable(buffer, indio_dev); | |
603 | } | |
604 | ||
8e050996 LPC |
605 | static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev, |
606 | struct iio_buffer *buffer) | |
607 | { | |
608 | unsigned int bytes; | |
609 | ||
610 | if (!buffer->access->set_bytes_per_datum) | |
611 | return; | |
612 | ||
613 | bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask, | |
614 | buffer->scan_timestamp); | |
615 | ||
616 | buffer->access->set_bytes_per_datum(buffer, bytes); | |
617 | } | |
618 | ||
fcc1b2f5 LPC |
619 | static int iio_buffer_request_update(struct iio_dev *indio_dev, |
620 | struct iio_buffer *buffer) | |
621 | { | |
622 | int ret; | |
623 | ||
624 | iio_buffer_update_bytes_per_datum(indio_dev, buffer); | |
625 | if (buffer->access->request_update) { | |
626 | ret = buffer->access->request_update(buffer); | |
627 | if (ret) { | |
628 | dev_dbg(&indio_dev->dev, | |
629 | "Buffer not started: buffer parameter update failed (%d)\n", | |
630 | ret); | |
631 | return ret; | |
632 | } | |
633 | } | |
634 | ||
635 | return 0; | |
636 | } | |
637 | ||
248be5aa LPC |
638 | static void iio_free_scan_mask(struct iio_dev *indio_dev, |
639 | const unsigned long *mask) | |
640 | { | |
641 | /* If the mask is dynamically allocated free it, otherwise do nothing */ | |
642 | if (!indio_dev->available_scan_masks) | |
643 | kfree(mask); | |
644 | } | |
645 | ||
6e509c4d LPC |
646 | struct iio_device_config { |
647 | unsigned int mode; | |
f0566c0c | 648 | unsigned int watermark; |
6e509c4d LPC |
649 | const unsigned long *scan_mask; |
650 | unsigned int scan_bytes; | |
651 | bool scan_timestamp; | |
652 | }; | |
653 | ||
654 | static int iio_verify_update(struct iio_dev *indio_dev, | |
655 | struct iio_buffer *insert_buffer, struct iio_buffer *remove_buffer, | |
656 | struct iio_device_config *config) | |
657 | { | |
658 | unsigned long *compound_mask; | |
659 | const unsigned long *scan_mask; | |
1e1ec286 | 660 | bool strict_scanmask = false; |
6e509c4d LPC |
661 | struct iio_buffer *buffer; |
662 | bool scan_timestamp; | |
225d59ad | 663 | unsigned int modes; |
6e509c4d LPC |
664 | |
665 | memset(config, 0, sizeof(*config)); | |
1bef2c1d | 666 | config->watermark = ~0; |
6e509c4d LPC |
667 | |
668 | /* | |
669 | * If there is just one buffer and we are removing it there is nothing | |
670 | * to verify. | |
671 | */ | |
672 | if (remove_buffer && !insert_buffer && | |
673 | list_is_singular(&indio_dev->buffer_list)) | |
674 | return 0; | |
675 | ||
225d59ad LPC |
676 | modes = indio_dev->modes; |
677 | ||
678 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
679 | if (buffer == remove_buffer) | |
680 | continue; | |
681 | modes &= buffer->access->modes; | |
f0566c0c | 682 | config->watermark = min(config->watermark, buffer->watermark); |
225d59ad LPC |
683 | } |
684 | ||
f0566c0c | 685 | if (insert_buffer) { |
225d59ad | 686 | modes &= insert_buffer->access->modes; |
f0566c0c LPC |
687 | config->watermark = min(config->watermark, |
688 | insert_buffer->watermark); | |
689 | } | |
225d59ad | 690 | |
6e509c4d | 691 | /* Definitely possible for devices to support both of these. */ |
225d59ad | 692 | if ((modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) { |
6e509c4d | 693 | config->mode = INDIO_BUFFER_TRIGGERED; |
225d59ad | 694 | } else if (modes & INDIO_BUFFER_HARDWARE) { |
1e1ec286 LPC |
695 | /* |
696 | * Keep things simple for now and only allow a single buffer to | |
697 | * be connected in hardware mode. | |
698 | */ | |
699 | if (insert_buffer && !list_empty(&indio_dev->buffer_list)) | |
700 | return -EINVAL; | |
6e509c4d | 701 | config->mode = INDIO_BUFFER_HARDWARE; |
1e1ec286 | 702 | strict_scanmask = true; |
225d59ad | 703 | } else if (modes & INDIO_BUFFER_SOFTWARE) { |
6e509c4d LPC |
704 | config->mode = INDIO_BUFFER_SOFTWARE; |
705 | } else { | |
706 | /* Can only occur on first buffer */ | |
707 | if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) | |
708 | dev_dbg(&indio_dev->dev, "Buffer not started: no trigger\n"); | |
709 | return -EINVAL; | |
710 | } | |
711 | ||
712 | /* What scan mask do we actually have? */ | |
713 | compound_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), | |
714 | sizeof(long), GFP_KERNEL); | |
715 | if (compound_mask == NULL) | |
716 | return -ENOMEM; | |
717 | ||
718 | scan_timestamp = false; | |
719 | ||
720 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
721 | if (buffer == remove_buffer) | |
722 | continue; | |
723 | bitmap_or(compound_mask, compound_mask, buffer->scan_mask, | |
724 | indio_dev->masklength); | |
725 | scan_timestamp |= buffer->scan_timestamp; | |
726 | } | |
727 | ||
728 | if (insert_buffer) { | |
729 | bitmap_or(compound_mask, compound_mask, | |
730 | insert_buffer->scan_mask, indio_dev->masklength); | |
731 | scan_timestamp |= insert_buffer->scan_timestamp; | |
732 | } | |
733 | ||
734 | if (indio_dev->available_scan_masks) { | |
735 | scan_mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
736 | indio_dev->masklength, | |
1e1ec286 LPC |
737 | compound_mask, |
738 | strict_scanmask); | |
6e509c4d LPC |
739 | kfree(compound_mask); |
740 | if (scan_mask == NULL) | |
741 | return -EINVAL; | |
742 | } else { | |
743 | scan_mask = compound_mask; | |
744 | } | |
745 | ||
746 | config->scan_bytes = iio_compute_scan_bytes(indio_dev, | |
747 | scan_mask, scan_timestamp); | |
748 | config->scan_mask = scan_mask; | |
749 | config->scan_timestamp = scan_timestamp; | |
750 | ||
751 | return 0; | |
752 | } | |
753 | ||
623d74e3 LPC |
754 | static int iio_enable_buffers(struct iio_dev *indio_dev, |
755 | struct iio_device_config *config) | |
6b3b58ed | 756 | { |
e18a2ad4 | 757 | struct iio_buffer *buffer; |
84b36ce5 | 758 | int ret; |
fcc1b2f5 | 759 | |
623d74e3 LPC |
760 | indio_dev->active_scan_mask = config->scan_mask; |
761 | indio_dev->scan_timestamp = config->scan_timestamp; | |
762 | indio_dev->scan_bytes = config->scan_bytes; | |
aff1eb4e | 763 | |
5ada4ea9 JC |
764 | iio_update_demux(indio_dev); |
765 | ||
84b36ce5 JC |
766 | /* Wind up again */ |
767 | if (indio_dev->setup_ops->preenable) { | |
768 | ret = indio_dev->setup_ops->preenable(indio_dev); | |
769 | if (ret) { | |
63223c5f | 770 | dev_dbg(&indio_dev->dev, |
bec1889d | 771 | "Buffer not started: buffer preenable failed (%d)\n", ret); |
623d74e3 | 772 | goto err_undo_config; |
84b36ce5 JC |
773 | } |
774 | } | |
6e509c4d | 775 | |
84b36ce5 JC |
776 | if (indio_dev->info->update_scan_mode) { |
777 | ret = indio_dev->info | |
5ada4ea9 JC |
778 | ->update_scan_mode(indio_dev, |
779 | indio_dev->active_scan_mask); | |
84b36ce5 | 780 | if (ret < 0) { |
63223c5f LPC |
781 | dev_dbg(&indio_dev->dev, |
782 | "Buffer not started: update scan mode failed (%d)\n", | |
783 | ret); | |
623d74e3 | 784 | goto err_run_postdisable; |
84b36ce5 JC |
785 | } |
786 | } | |
6e509c4d | 787 | |
f0566c0c LPC |
788 | if (indio_dev->info->hwfifo_set_watermark) |
789 | indio_dev->info->hwfifo_set_watermark(indio_dev, | |
790 | config->watermark); | |
791 | ||
e18a2ad4 LPC |
792 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { |
793 | ret = iio_buffer_enable(buffer, indio_dev); | |
794 | if (ret) | |
795 | goto err_disable_buffers; | |
796 | } | |
797 | ||
623d74e3 | 798 | indio_dev->currentmode = config->mode; |
84b36ce5 JC |
799 | |
800 | if (indio_dev->setup_ops->postenable) { | |
801 | ret = indio_dev->setup_ops->postenable(indio_dev); | |
802 | if (ret) { | |
63223c5f | 803 | dev_dbg(&indio_dev->dev, |
bec1889d | 804 | "Buffer not started: postenable failed (%d)\n", ret); |
e18a2ad4 | 805 | goto err_disable_buffers; |
84b36ce5 JC |
806 | } |
807 | } | |
808 | ||
6e509c4d | 809 | return 0; |
84b36ce5 | 810 | |
e18a2ad4 LPC |
811 | err_disable_buffers: |
812 | list_for_each_entry_continue_reverse(buffer, &indio_dev->buffer_list, | |
813 | buffer_list) | |
814 | iio_buffer_disable(buffer, indio_dev); | |
623d74e3 | 815 | err_run_postdisable: |
84b36ce5 | 816 | indio_dev->currentmode = INDIO_DIRECT_MODE; |
84b36ce5 JC |
817 | if (indio_dev->setup_ops->postdisable) |
818 | indio_dev->setup_ops->postdisable(indio_dev); | |
623d74e3 LPC |
819 | err_undo_config: |
820 | indio_dev->active_scan_mask = NULL; | |
821 | ||
84b36ce5 | 822 | return ret; |
623d74e3 LPC |
823 | } |
824 | ||
825 | static int iio_disable_buffers(struct iio_dev *indio_dev) | |
826 | { | |
e18a2ad4 | 827 | struct iio_buffer *buffer; |
1250186a LPC |
828 | int ret = 0; |
829 | int ret2; | |
623d74e3 LPC |
830 | |
831 | /* Wind down existing buffers - iff there are any */ | |
832 | if (list_empty(&indio_dev->buffer_list)) | |
833 | return 0; | |
834 | ||
1250186a LPC |
835 | /* |
836 | * If things go wrong at some step in disable we still need to continue | |
837 | * to perform the other steps, otherwise we leave the device in a | |
838 | * inconsistent state. We return the error code for the first error we | |
839 | * encountered. | |
840 | */ | |
841 | ||
623d74e3 | 842 | if (indio_dev->setup_ops->predisable) { |
1250186a LPC |
843 | ret2 = indio_dev->setup_ops->predisable(indio_dev); |
844 | if (ret2 && !ret) | |
845 | ret = ret2; | |
623d74e3 | 846 | } |
e18a2ad4 LPC |
847 | |
848 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
849 | ret2 = iio_buffer_disable(buffer, indio_dev); | |
850 | if (ret2 && !ret) | |
851 | ret = ret2; | |
852 | } | |
623d74e3 LPC |
853 | |
854 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
855 | ||
856 | if (indio_dev->setup_ops->postdisable) { | |
1250186a LPC |
857 | ret2 = indio_dev->setup_ops->postdisable(indio_dev); |
858 | if (ret2 && !ret) | |
859 | ret = ret2; | |
623d74e3 LPC |
860 | } |
861 | ||
1250186a LPC |
862 | iio_free_scan_mask(indio_dev, indio_dev->active_scan_mask); |
863 | indio_dev->active_scan_mask = NULL; | |
864 | ||
865 | return ret; | |
623d74e3 LPC |
866 | } |
867 | ||
868 | static int __iio_update_buffers(struct iio_dev *indio_dev, | |
869 | struct iio_buffer *insert_buffer, | |
870 | struct iio_buffer *remove_buffer) | |
871 | { | |
623d74e3 | 872 | struct iio_device_config new_config; |
1250186a | 873 | int ret; |
623d74e3 LPC |
874 | |
875 | ret = iio_verify_update(indio_dev, insert_buffer, remove_buffer, | |
876 | &new_config); | |
877 | if (ret) | |
878 | return ret; | |
879 | ||
880 | if (insert_buffer) { | |
881 | ret = iio_buffer_request_update(indio_dev, insert_buffer); | |
882 | if (ret) | |
883 | goto err_free_config; | |
884 | } | |
885 | ||
623d74e3 | 886 | ret = iio_disable_buffers(indio_dev); |
1250186a LPC |
887 | if (ret) |
888 | goto err_deactivate_all; | |
623d74e3 LPC |
889 | |
890 | if (remove_buffer) | |
891 | iio_buffer_deactivate(remove_buffer); | |
892 | if (insert_buffer) | |
893 | iio_buffer_activate(indio_dev, insert_buffer); | |
894 | ||
895 | /* If no buffers in list, we are done */ | |
1250186a | 896 | if (list_empty(&indio_dev->buffer_list)) |
623d74e3 | 897 | return 0; |
623d74e3 LPC |
898 | |
899 | ret = iio_enable_buffers(indio_dev, &new_config); | |
1250186a LPC |
900 | if (ret) |
901 | goto err_deactivate_all; | |
623d74e3 | 902 | |
623d74e3 | 903 | return 0; |
6e509c4d | 904 | |
1250186a LPC |
905 | err_deactivate_all: |
906 | /* | |
907 | * We've already verified that the config is valid earlier. If things go | |
908 | * wrong in either enable or disable the most likely reason is an IO | |
909 | * error from the device. In this case there is no good recovery | |
910 | * strategy. Just make sure to disable everything and leave the device | |
911 | * in a sane state. With a bit of luck the device might come back to | |
912 | * life again later and userspace can try again. | |
913 | */ | |
914 | iio_buffer_deactivate_all(indio_dev); | |
915 | ||
6e509c4d LPC |
916 | err_free_config: |
917 | iio_free_scan_mask(indio_dev, new_config.scan_mask); | |
918 | return ret; | |
84b36ce5 | 919 | } |
a9519456 LPC |
920 | |
921 | int iio_update_buffers(struct iio_dev *indio_dev, | |
922 | struct iio_buffer *insert_buffer, | |
923 | struct iio_buffer *remove_buffer) | |
924 | { | |
925 | int ret; | |
926 | ||
3909fab5 LPC |
927 | if (insert_buffer == remove_buffer) |
928 | return 0; | |
929 | ||
a9519456 LPC |
930 | mutex_lock(&indio_dev->info_exist_lock); |
931 | mutex_lock(&indio_dev->mlock); | |
932 | ||
3909fab5 LPC |
933 | if (insert_buffer && iio_buffer_is_active(insert_buffer)) |
934 | insert_buffer = NULL; | |
935 | ||
936 | if (remove_buffer && !iio_buffer_is_active(remove_buffer)) | |
937 | remove_buffer = NULL; | |
938 | ||
939 | if (!insert_buffer && !remove_buffer) { | |
940 | ret = 0; | |
941 | goto out_unlock; | |
942 | } | |
943 | ||
a9519456 LPC |
944 | if (indio_dev->info == NULL) { |
945 | ret = -ENODEV; | |
946 | goto out_unlock; | |
947 | } | |
948 | ||
949 | ret = __iio_update_buffers(indio_dev, insert_buffer, remove_buffer); | |
950 | ||
951 | out_unlock: | |
952 | mutex_unlock(&indio_dev->mlock); | |
953 | mutex_unlock(&indio_dev->info_exist_lock); | |
954 | ||
955 | return ret; | |
956 | } | |
84b36ce5 JC |
957 | EXPORT_SYMBOL_GPL(iio_update_buffers); |
958 | ||
623d74e3 LPC |
959 | void iio_disable_all_buffers(struct iio_dev *indio_dev) |
960 | { | |
623d74e3 | 961 | iio_disable_buffers(indio_dev); |
1250186a | 962 | iio_buffer_deactivate_all(indio_dev); |
623d74e3 LPC |
963 | } |
964 | ||
08e7e0ad LPC |
965 | static ssize_t iio_buffer_store_enable(struct device *dev, |
966 | struct device_attribute *attr, | |
967 | const char *buf, | |
968 | size_t len) | |
84b36ce5 JC |
969 | { |
970 | int ret; | |
971 | bool requested_state; | |
972 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
84b36ce5 JC |
973 | bool inlist; |
974 | ||
975 | ret = strtobool(buf, &requested_state); | |
976 | if (ret < 0) | |
977 | return ret; | |
978 | ||
979 | mutex_lock(&indio_dev->mlock); | |
980 | ||
981 | /* Find out if it is in the list */ | |
705ee2c9 | 982 | inlist = iio_buffer_is_active(indio_dev->buffer); |
84b36ce5 JC |
983 | /* Already in desired state */ |
984 | if (inlist == requested_state) | |
985 | goto done; | |
986 | ||
987 | if (requested_state) | |
a9519456 | 988 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
989 | indio_dev->buffer, NULL); |
990 | else | |
a9519456 | 991 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
992 | NULL, indio_dev->buffer); |
993 | ||
84b36ce5 JC |
994 | done: |
995 | mutex_unlock(&indio_dev->mlock); | |
996 | return (ret < 0) ? ret : len; | |
997 | } | |
84b36ce5 | 998 | |
d967cb6b LPC |
999 | static const char * const iio_scan_elements_group_name = "scan_elements"; |
1000 | ||
37d34556 JC |
1001 | static ssize_t iio_buffer_show_watermark(struct device *dev, |
1002 | struct device_attribute *attr, | |
1003 | char *buf) | |
1004 | { | |
1005 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1006 | struct iio_buffer *buffer = indio_dev->buffer; | |
1007 | ||
1008 | return sprintf(buf, "%u\n", buffer->watermark); | |
1009 | } | |
1010 | ||
1011 | static ssize_t iio_buffer_store_watermark(struct device *dev, | |
1012 | struct device_attribute *attr, | |
1013 | const char *buf, | |
1014 | size_t len) | |
1015 | { | |
1016 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1017 | struct iio_buffer *buffer = indio_dev->buffer; | |
1018 | unsigned int val; | |
1019 | int ret; | |
1020 | ||
1021 | ret = kstrtouint(buf, 10, &val); | |
1022 | if (ret) | |
1023 | return ret; | |
1024 | if (!val) | |
1025 | return -EINVAL; | |
1026 | ||
1027 | mutex_lock(&indio_dev->mlock); | |
1028 | ||
1029 | if (val > buffer->length) { | |
1030 | ret = -EINVAL; | |
1031 | goto out; | |
1032 | } | |
1033 | ||
1034 | if (iio_buffer_is_active(indio_dev->buffer)) { | |
1035 | ret = -EBUSY; | |
1036 | goto out; | |
1037 | } | |
1038 | ||
1039 | buffer->watermark = val; | |
1040 | out: | |
1041 | mutex_unlock(&indio_dev->mlock); | |
1042 | ||
1043 | return ret ? ret : len; | |
1044 | } | |
1045 | ||
08e7e0ad LPC |
1046 | static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length, |
1047 | iio_buffer_write_length); | |
8d92db28 LPC |
1048 | static struct device_attribute dev_attr_length_ro = __ATTR(length, |
1049 | S_IRUGO, iio_buffer_read_length, NULL); | |
08e7e0ad LPC |
1050 | static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, |
1051 | iio_buffer_show_enable, iio_buffer_store_enable); | |
37d34556 JC |
1052 | static DEVICE_ATTR(watermark, S_IRUGO | S_IWUSR, |
1053 | iio_buffer_show_watermark, iio_buffer_store_watermark); | |
b440655b LPC |
1054 | static struct device_attribute dev_attr_watermark_ro = __ATTR(watermark, |
1055 | S_IRUGO, iio_buffer_show_watermark, NULL); | |
08e7e0ad | 1056 | |
6da9b382 OP |
1057 | static struct attribute *iio_buffer_attrs[] = { |
1058 | &dev_attr_length.attr, | |
1059 | &dev_attr_enable.attr, | |
37d34556 | 1060 | &dev_attr_watermark.attr, |
6da9b382 OP |
1061 | }; |
1062 | ||
d967cb6b LPC |
1063 | int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev) |
1064 | { | |
1065 | struct iio_dev_attr *p; | |
1066 | struct attribute **attr; | |
1067 | struct iio_buffer *buffer = indio_dev->buffer; | |
1068 | int ret, i, attrn, attrcount, attrcount_orig = 0; | |
1069 | const struct iio_chan_spec *channels; | |
1070 | ||
629bc023 LPC |
1071 | channels = indio_dev->channels; |
1072 | if (channels) { | |
1073 | int ml = indio_dev->masklength; | |
1074 | ||
1075 | for (i = 0; i < indio_dev->num_channels; i++) | |
1076 | ml = max(ml, channels[i].scan_index + 1); | |
1077 | indio_dev->masklength = ml; | |
1078 | } | |
1079 | ||
d967cb6b LPC |
1080 | if (!buffer) |
1081 | return 0; | |
1082 | ||
08e7e0ad LPC |
1083 | attrcount = 0; |
1084 | if (buffer->attrs) { | |
1085 | while (buffer->attrs[attrcount] != NULL) | |
1086 | attrcount++; | |
1087 | } | |
1088 | ||
6da9b382 OP |
1089 | attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, |
1090 | sizeof(struct attribute *), GFP_KERNEL); | |
1091 | if (!attr) | |
08e7e0ad LPC |
1092 | return -ENOMEM; |
1093 | ||
6da9b382 OP |
1094 | memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); |
1095 | if (!buffer->access->set_length) | |
1096 | attr[0] = &dev_attr_length_ro.attr; | |
1097 | ||
b440655b LPC |
1098 | if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) |
1099 | attr[2] = &dev_attr_watermark_ro.attr; | |
1100 | ||
08e7e0ad | 1101 | if (buffer->attrs) |
6da9b382 OP |
1102 | memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, |
1103 | sizeof(struct attribute *) * attrcount); | |
1104 | ||
1105 | attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; | |
1106 | ||
1107 | buffer->buffer_group.name = "buffer"; | |
1108 | buffer->buffer_group.attrs = attr; | |
08e7e0ad LPC |
1109 | |
1110 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->buffer_group; | |
1111 | ||
d967cb6b LPC |
1112 | if (buffer->scan_el_attrs != NULL) { |
1113 | attr = buffer->scan_el_attrs->attrs; | |
1114 | while (*attr++ != NULL) | |
1115 | attrcount_orig++; | |
1116 | } | |
1117 | attrcount = attrcount_orig; | |
1118 | INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); | |
1119 | channels = indio_dev->channels; | |
1120 | if (channels) { | |
1121 | /* new magic */ | |
1122 | for (i = 0; i < indio_dev->num_channels; i++) { | |
1123 | if (channels[i].scan_index < 0) | |
1124 | continue; | |
1125 | ||
d967cb6b LPC |
1126 | ret = iio_buffer_add_channel_sysfs(indio_dev, |
1127 | &channels[i]); | |
1128 | if (ret < 0) | |
1129 | goto error_cleanup_dynamic; | |
1130 | attrcount += ret; | |
1131 | if (channels[i].type == IIO_TIMESTAMP) | |
1132 | indio_dev->scan_index_timestamp = | |
1133 | channels[i].scan_index; | |
1134 | } | |
1135 | if (indio_dev->masklength && buffer->scan_mask == NULL) { | |
1136 | buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), | |
1137 | sizeof(*buffer->scan_mask), | |
1138 | GFP_KERNEL); | |
1139 | if (buffer->scan_mask == NULL) { | |
1140 | ret = -ENOMEM; | |
1141 | goto error_cleanup_dynamic; | |
1142 | } | |
1143 | } | |
1144 | } | |
1145 | ||
1146 | buffer->scan_el_group.name = iio_scan_elements_group_name; | |
1147 | ||
1148 | buffer->scan_el_group.attrs = kcalloc(attrcount + 1, | |
1149 | sizeof(buffer->scan_el_group.attrs[0]), | |
1150 | GFP_KERNEL); | |
1151 | if (buffer->scan_el_group.attrs == NULL) { | |
1152 | ret = -ENOMEM; | |
1153 | goto error_free_scan_mask; | |
1154 | } | |
1155 | if (buffer->scan_el_attrs) | |
1156 | memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs, | |
1157 | sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig); | |
1158 | attrn = attrcount_orig; | |
1159 | ||
1160 | list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l) | |
1161 | buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr; | |
1162 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group; | |
1163 | ||
1164 | return 0; | |
1165 | ||
1166 | error_free_scan_mask: | |
1167 | kfree(buffer->scan_mask); | |
1168 | error_cleanup_dynamic: | |
1169 | iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); | |
08e7e0ad | 1170 | kfree(indio_dev->buffer->buffer_group.attrs); |
d967cb6b LPC |
1171 | |
1172 | return ret; | |
1173 | } | |
1174 | ||
1175 | void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev) | |
1176 | { | |
1177 | if (!indio_dev->buffer) | |
1178 | return; | |
1179 | ||
1180 | kfree(indio_dev->buffer->scan_mask); | |
08e7e0ad | 1181 | kfree(indio_dev->buffer->buffer_group.attrs); |
d967cb6b LPC |
1182 | kfree(indio_dev->buffer->scan_el_group.attrs); |
1183 | iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list); | |
1184 | } | |
1185 | ||
81636632 LPC |
1186 | /** |
1187 | * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected | |
1188 | * @indio_dev: the iio device | |
1189 | * @mask: scan mask to be checked | |
1190 | * | |
1191 | * Return true if exactly one bit is set in the scan mask, false otherwise. It | |
1192 | * can be used for devices where only one channel can be active for sampling at | |
1193 | * a time. | |
1194 | */ | |
1195 | bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, | |
1196 | const unsigned long *mask) | |
1197 | { | |
1198 | return bitmap_weight(mask, indio_dev->masklength) == 1; | |
1199 | } | |
1200 | EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot); | |
1201 | ||
f79a9098 JC |
1202 | int iio_scan_mask_query(struct iio_dev *indio_dev, |
1203 | struct iio_buffer *buffer, int bit) | |
32b5eeca | 1204 | { |
f8c6f4e9 | 1205 | if (bit > indio_dev->masklength) |
32b5eeca JC |
1206 | return -EINVAL; |
1207 | ||
14555b14 | 1208 | if (!buffer->scan_mask) |
32b5eeca | 1209 | return 0; |
32b5eeca | 1210 | |
2076a20f AB |
1211 | /* Ensure return value is 0 or 1. */ |
1212 | return !!test_bit(bit, buffer->scan_mask); | |
32b5eeca JC |
1213 | }; |
1214 | EXPORT_SYMBOL_GPL(iio_scan_mask_query); | |
5ada4ea9 JC |
1215 | |
1216 | /** | |
0123635a | 1217 | * struct iio_demux_table - table describing demux memcpy ops |
5ada4ea9 | 1218 | * @from: index to copy from |
99698b45 | 1219 | * @to: index to copy to |
5ada4ea9 JC |
1220 | * @length: how many bytes to copy |
1221 | * @l: list head used for management | |
1222 | */ | |
1223 | struct iio_demux_table { | |
1224 | unsigned from; | |
1225 | unsigned to; | |
1226 | unsigned length; | |
1227 | struct list_head l; | |
1228 | }; | |
1229 | ||
5d65d920 LPC |
1230 | static const void *iio_demux(struct iio_buffer *buffer, |
1231 | const void *datain) | |
5ada4ea9 JC |
1232 | { |
1233 | struct iio_demux_table *t; | |
1234 | ||
1235 | if (list_empty(&buffer->demux_list)) | |
1236 | return datain; | |
1237 | list_for_each_entry(t, &buffer->demux_list, l) | |
1238 | memcpy(buffer->demux_bounce + t->to, | |
1239 | datain + t->from, t->length); | |
1240 | ||
1241 | return buffer->demux_bounce; | |
1242 | } | |
1243 | ||
5d65d920 | 1244 | static int iio_push_to_buffer(struct iio_buffer *buffer, const void *data) |
5ada4ea9 | 1245 | { |
5d65d920 | 1246 | const void *dataout = iio_demux(buffer, data); |
37d34556 JC |
1247 | int ret; |
1248 | ||
1249 | ret = buffer->access->store_to(buffer, dataout); | |
1250 | if (ret) | |
1251 | return ret; | |
5ada4ea9 | 1252 | |
37d34556 JC |
1253 | /* |
1254 | * We can't just test for watermark to decide if we wake the poll queue | |
1255 | * because read may request less samples than the watermark. | |
1256 | */ | |
1257 | wake_up_interruptible_poll(&buffer->pollq, POLLIN | POLLRDNORM); | |
1258 | return 0; | |
5ada4ea9 | 1259 | } |
5ada4ea9 | 1260 | |
842cd100 JC |
1261 | static void iio_buffer_demux_free(struct iio_buffer *buffer) |
1262 | { | |
1263 | struct iio_demux_table *p, *q; | |
1264 | list_for_each_entry_safe(p, q, &buffer->demux_list, l) { | |
1265 | list_del(&p->l); | |
1266 | kfree(p); | |
1267 | } | |
1268 | } | |
1269 | ||
84b36ce5 | 1270 | |
5d65d920 | 1271 | int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data) |
84b36ce5 JC |
1272 | { |
1273 | int ret; | |
1274 | struct iio_buffer *buf; | |
1275 | ||
1276 | list_for_each_entry(buf, &indio_dev->buffer_list, buffer_list) { | |
1277 | ret = iio_push_to_buffer(buf, data); | |
1278 | if (ret < 0) | |
1279 | return ret; | |
1280 | } | |
1281 | ||
1282 | return 0; | |
1283 | } | |
1284 | EXPORT_SYMBOL_GPL(iio_push_to_buffers); | |
1285 | ||
cbe88bcc LPC |
1286 | static int iio_buffer_add_demux(struct iio_buffer *buffer, |
1287 | struct iio_demux_table **p, unsigned int in_loc, unsigned int out_loc, | |
1288 | unsigned int length) | |
1289 | { | |
1290 | ||
1291 | if (*p && (*p)->from + (*p)->length == in_loc && | |
1292 | (*p)->to + (*p)->length == out_loc) { | |
1293 | (*p)->length += length; | |
1294 | } else { | |
7cdca178 | 1295 | *p = kmalloc(sizeof(**p), GFP_KERNEL); |
cbe88bcc LPC |
1296 | if (*p == NULL) |
1297 | return -ENOMEM; | |
1298 | (*p)->from = in_loc; | |
1299 | (*p)->to = out_loc; | |
1300 | (*p)->length = length; | |
1301 | list_add_tail(&(*p)->l, &buffer->demux_list); | |
1302 | } | |
1303 | ||
1304 | return 0; | |
1305 | } | |
1306 | ||
84b36ce5 JC |
1307 | static int iio_buffer_update_demux(struct iio_dev *indio_dev, |
1308 | struct iio_buffer *buffer) | |
5ada4ea9 | 1309 | { |
5ada4ea9 JC |
1310 | int ret, in_ind = -1, out_ind, length; |
1311 | unsigned in_loc = 0, out_loc = 0; | |
cbe88bcc | 1312 | struct iio_demux_table *p = NULL; |
5ada4ea9 JC |
1313 | |
1314 | /* Clear out any old demux */ | |
842cd100 | 1315 | iio_buffer_demux_free(buffer); |
5ada4ea9 JC |
1316 | kfree(buffer->demux_bounce); |
1317 | buffer->demux_bounce = NULL; | |
1318 | ||
1319 | /* First work out which scan mode we will actually have */ | |
1320 | if (bitmap_equal(indio_dev->active_scan_mask, | |
1321 | buffer->scan_mask, | |
1322 | indio_dev->masklength)) | |
1323 | return 0; | |
1324 | ||
1325 | /* Now we have the two masks, work from least sig and build up sizes */ | |
1326 | for_each_set_bit(out_ind, | |
61bd55ce | 1327 | buffer->scan_mask, |
5ada4ea9 JC |
1328 | indio_dev->masklength) { |
1329 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
1330 | indio_dev->masklength, | |
1331 | in_ind + 1); | |
1332 | while (in_ind != out_ind) { | |
1333 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
1334 | indio_dev->masklength, | |
1335 | in_ind + 1); | |
182b4905 | 1336 | length = iio_storage_bytes_for_si(indio_dev, in_ind); |
5ada4ea9 | 1337 | /* Make sure we are aligned */ |
61072dbc | 1338 | in_loc = roundup(in_loc, length) + length; |
5ada4ea9 | 1339 | } |
182b4905 | 1340 | length = iio_storage_bytes_for_si(indio_dev, in_ind); |
61072dbc LPC |
1341 | out_loc = roundup(out_loc, length); |
1342 | in_loc = roundup(in_loc, length); | |
cbe88bcc LPC |
1343 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); |
1344 | if (ret) | |
1345 | goto error_clear_mux_table; | |
5ada4ea9 JC |
1346 | out_loc += length; |
1347 | in_loc += length; | |
1348 | } | |
1349 | /* Relies on scan_timestamp being last */ | |
1350 | if (buffer->scan_timestamp) { | |
182b4905 | 1351 | length = iio_storage_bytes_for_timestamp(indio_dev); |
61072dbc LPC |
1352 | out_loc = roundup(out_loc, length); |
1353 | in_loc = roundup(in_loc, length); | |
cbe88bcc LPC |
1354 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); |
1355 | if (ret) | |
1356 | goto error_clear_mux_table; | |
5ada4ea9 JC |
1357 | out_loc += length; |
1358 | in_loc += length; | |
1359 | } | |
1360 | buffer->demux_bounce = kzalloc(out_loc, GFP_KERNEL); | |
1361 | if (buffer->demux_bounce == NULL) { | |
1362 | ret = -ENOMEM; | |
1363 | goto error_clear_mux_table; | |
1364 | } | |
1365 | return 0; | |
1366 | ||
1367 | error_clear_mux_table: | |
842cd100 JC |
1368 | iio_buffer_demux_free(buffer); |
1369 | ||
5ada4ea9 JC |
1370 | return ret; |
1371 | } | |
84b36ce5 JC |
1372 | |
1373 | int iio_update_demux(struct iio_dev *indio_dev) | |
1374 | { | |
1375 | struct iio_buffer *buffer; | |
1376 | int ret; | |
1377 | ||
1378 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
1379 | ret = iio_buffer_update_demux(indio_dev, buffer); | |
1380 | if (ret < 0) | |
1381 | goto error_clear_mux_table; | |
1382 | } | |
1383 | return 0; | |
1384 | ||
1385 | error_clear_mux_table: | |
1386 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) | |
1387 | iio_buffer_demux_free(buffer); | |
1388 | ||
1389 | return ret; | |
1390 | } | |
5ada4ea9 | 1391 | EXPORT_SYMBOL_GPL(iio_update_demux); |
9e69c935 LPC |
1392 | |
1393 | /** | |
1394 | * iio_buffer_release() - Free a buffer's resources | |
1395 | * @ref: Pointer to the kref embedded in the iio_buffer struct | |
1396 | * | |
1397 | * This function is called when the last reference to the buffer has been | |
1398 | * dropped. It will typically free all resources allocated by the buffer. Do not | |
1399 | * call this function manually, always use iio_buffer_put() when done using a | |
1400 | * buffer. | |
1401 | */ | |
1402 | static void iio_buffer_release(struct kref *ref) | |
1403 | { | |
1404 | struct iio_buffer *buffer = container_of(ref, struct iio_buffer, ref); | |
1405 | ||
1406 | buffer->access->release(buffer); | |
1407 | } | |
1408 | ||
1409 | /** | |
1410 | * iio_buffer_get() - Grab a reference to the buffer | |
1411 | * @buffer: The buffer to grab a reference for, may be NULL | |
1412 | * | |
1413 | * Returns the pointer to the buffer that was passed into the function. | |
1414 | */ | |
1415 | struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer) | |
1416 | { | |
1417 | if (buffer) | |
1418 | kref_get(&buffer->ref); | |
1419 | ||
1420 | return buffer; | |
1421 | } | |
1422 | EXPORT_SYMBOL_GPL(iio_buffer_get); | |
1423 | ||
1424 | /** | |
1425 | * iio_buffer_put() - Release the reference to the buffer | |
1426 | * @buffer: The buffer to release the reference for, may be NULL | |
1427 | */ | |
1428 | void iio_buffer_put(struct iio_buffer *buffer) | |
1429 | { | |
1430 | if (buffer) | |
1431 | kref_put(&buffer->ref, iio_buffer_release); | |
1432 | } | |
1433 | EXPORT_SYMBOL_GPL(iio_buffer_put); |