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