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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
7026ea4b JC |
2 | /* The industrial I/O core |
3 | * | |
4 | * Copyright (c) 2008 Jonathan Cameron | |
5 | * | |
14555b14 | 6 | * Handling of buffer allocation / resizing. |
7026ea4b | 7 | * |
7026ea4b JC |
8 | * Things to look at here. |
9 | * - Better memory allocation techniques? | |
10 | * - Alternative access techniques? | |
11 | */ | |
12 | #include <linux/kernel.h> | |
8e336a72 | 13 | #include <linux/export.h> |
7026ea4b | 14 | #include <linux/device.h> |
7026ea4b | 15 | #include <linux/fs.h> |
7026ea4b | 16 | #include <linux/cdev.h> |
5a0e3ad6 | 17 | #include <linux/slab.h> |
a7348347 | 18 | #include <linux/poll.h> |
174cd4b1 | 19 | #include <linux/sched/signal.h> |
7026ea4b | 20 | |
06458e27 | 21 | #include <linux/iio/iio.h> |
df9c1c42 | 22 | #include "iio_core.h" |
06458e27 JC |
23 | #include <linux/iio/sysfs.h> |
24 | #include <linux/iio/buffer.h> | |
33dd94cb | 25 | #include <linux/iio/buffer_impl.h> |
7026ea4b | 26 | |
8310b86c JC |
27 | static const char * const iio_endian_prefix[] = { |
28 | [IIO_BE] = "be", | |
29 | [IIO_LE] = "le", | |
30 | }; | |
7026ea4b | 31 | |
705ee2c9 | 32 | static bool iio_buffer_is_active(struct iio_buffer *buf) |
84b36ce5 | 33 | { |
705ee2c9 | 34 | return !list_empty(&buf->buffer_list); |
84b36ce5 JC |
35 | } |
36 | ||
37d34556 | 37 | static size_t iio_buffer_data_available(struct iio_buffer *buf) |
647cc7b9 | 38 | { |
9dd4694d | 39 | return buf->access->data_available(buf); |
647cc7b9 LPC |
40 | } |
41 | ||
f4f4673b OP |
42 | static int iio_buffer_flush_hwfifo(struct iio_dev *indio_dev, |
43 | struct iio_buffer *buf, size_t required) | |
44 | { | |
45 | if (!indio_dev->info->hwfifo_flush_to_buffer) | |
46 | return -ENODEV; | |
47 | ||
48 | return indio_dev->info->hwfifo_flush_to_buffer(indio_dev, required); | |
49 | } | |
50 | ||
37d34556 | 51 | static bool iio_buffer_ready(struct iio_dev *indio_dev, struct iio_buffer *buf, |
f4f4673b | 52 | size_t to_wait, int to_flush) |
37d34556 | 53 | { |
f4f4673b OP |
54 | size_t avail; |
55 | int flushed = 0; | |
56 | ||
37d34556 JC |
57 | /* wakeup if the device was unregistered */ |
58 | if (!indio_dev->info) | |
59 | return true; | |
60 | ||
61 | /* drain the buffer if it was disabled */ | |
f4f4673b | 62 | if (!iio_buffer_is_active(buf)) { |
37d34556 | 63 | to_wait = min_t(size_t, to_wait, 1); |
f4f4673b OP |
64 | to_flush = 0; |
65 | } | |
66 | ||
67 | avail = iio_buffer_data_available(buf); | |
37d34556 | 68 | |
f4f4673b OP |
69 | if (avail >= to_wait) { |
70 | /* force a flush for non-blocking reads */ | |
c6f67a1f OP |
71 | if (!to_wait && avail < to_flush) |
72 | iio_buffer_flush_hwfifo(indio_dev, buf, | |
73 | to_flush - avail); | |
f4f4673b OP |
74 | return true; |
75 | } | |
76 | ||
77 | if (to_flush) | |
78 | flushed = iio_buffer_flush_hwfifo(indio_dev, buf, | |
79 | to_wait - avail); | |
80 | if (flushed <= 0) | |
81 | return false; | |
82 | ||
83 | if (avail + flushed >= to_wait) | |
37d34556 JC |
84 | return true; |
85 | ||
86 | return false; | |
87 | } | |
88 | ||
7026ea4b | 89 | /** |
f6d4033d | 90 | * iio_buffer_read_outer() - chrdev read for buffer access |
0123635a CO |
91 | * @filp: File structure pointer for the char device |
92 | * @buf: Destination buffer for iio buffer read | |
93 | * @n: First n bytes to read | |
94 | * @f_ps: Long offset provided by the user as a seek position | |
7026ea4b | 95 | * |
14555b14 JC |
96 | * This function relies on all buffer implementations having an |
97 | * iio_buffer as their first element. | |
0123635a CO |
98 | * |
99 | * Return: negative values corresponding to error codes or ret != 0 | |
100 | * for ending the reading activity | |
7026ea4b | 101 | **/ |
f6d4033d LPC |
102 | ssize_t iio_buffer_read_outer(struct file *filp, char __user *buf, |
103 | size_t n, loff_t *f_ps) | |
7026ea4b | 104 | { |
1aa04278 | 105 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 106 | struct iio_buffer *rb = indio_dev->buffer; |
fcf68f3c | 107 | DEFINE_WAIT_FUNC(wait, woken_wake_function); |
37d34556 | 108 | size_t datum_size; |
c6f67a1f | 109 | size_t to_wait; |
5dba4b14 | 110 | int ret = 0; |
d5857d65 | 111 | |
f18e7a06 LPC |
112 | if (!indio_dev->info) |
113 | return -ENODEV; | |
114 | ||
f6d4033d | 115 | if (!rb || !rb->access->read) |
7026ea4b | 116 | return -EINVAL; |
ee551a10 | 117 | |
37d34556 JC |
118 | datum_size = rb->bytes_per_datum; |
119 | ||
120 | /* | |
121 | * If datum_size is 0 there will never be anything to read from the | |
122 | * buffer, so signal end of file now. | |
123 | */ | |
124 | if (!datum_size) | |
125 | return 0; | |
126 | ||
c6f67a1f OP |
127 | if (filp->f_flags & O_NONBLOCK) |
128 | to_wait = 0; | |
129 | else | |
130 | to_wait = min_t(size_t, n / datum_size, rb->watermark); | |
37d34556 | 131 | |
fcf68f3c | 132 | add_wait_queue(&rb->pollq, &wait); |
ee551a10 | 133 | do { |
fcf68f3c BN |
134 | if (!indio_dev->info) { |
135 | ret = -ENODEV; | |
136 | break; | |
137 | } | |
138 | ||
139 | if (!iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size)) { | |
140 | if (signal_pending(current)) { | |
141 | ret = -ERESTARTSYS; | |
142 | break; | |
143 | } | |
144 | ||
145 | wait_woken(&wait, TASK_INTERRUPTIBLE, | |
146 | MAX_SCHEDULE_TIMEOUT); | |
147 | continue; | |
148 | } | |
ee551a10 | 149 | |
f6d4033d | 150 | ret = rb->access->read(rb, n, buf); |
ee551a10 LPC |
151 | if (ret == 0 && (filp->f_flags & O_NONBLOCK)) |
152 | ret = -EAGAIN; | |
5dba4b14 | 153 | } while (ret == 0); |
fcf68f3c | 154 | remove_wait_queue(&rb->pollq, &wait); |
ee551a10 LPC |
155 | |
156 | return ret; | |
7026ea4b JC |
157 | } |
158 | ||
a7348347 | 159 | /** |
14555b14 | 160 | * iio_buffer_poll() - poll the buffer to find out if it has data |
0123635a CO |
161 | * @filp: File structure pointer for device access |
162 | * @wait: Poll table structure pointer for which the driver adds | |
163 | * a wait queue | |
164 | * | |
a9a08845 | 165 | * Return: (EPOLLIN | EPOLLRDNORM) if data is available for reading |
0123635a | 166 | * or 0 for other cases |
a7348347 | 167 | */ |
afc9a42b | 168 | __poll_t iio_buffer_poll(struct file *filp, |
14555b14 | 169 | struct poll_table_struct *wait) |
a7348347 | 170 | { |
1aa04278 | 171 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 172 | struct iio_buffer *rb = indio_dev->buffer; |
a7348347 | 173 | |
4cd140bd | 174 | if (!indio_dev->info || rb == NULL) |
1bdc0293 | 175 | return 0; |
f18e7a06 | 176 | |
a7348347 | 177 | poll_wait(filp, &rb->pollq, wait); |
f4f4673b | 178 | if (iio_buffer_ready(indio_dev, rb, rb->watermark, 0)) |
a9a08845 | 179 | return EPOLLIN | EPOLLRDNORM; |
8d213f24 | 180 | return 0; |
a7348347 JC |
181 | } |
182 | ||
d2f0a48f LPC |
183 | /** |
184 | * iio_buffer_wakeup_poll - Wakes up the buffer waitqueue | |
185 | * @indio_dev: The IIO device | |
186 | * | |
187 | * Wakes up the event waitqueue used for poll(). Should usually | |
188 | * be called when the device is unregistered. | |
189 | */ | |
190 | void iio_buffer_wakeup_poll(struct iio_dev *indio_dev) | |
191 | { | |
ff3f7e04 AA |
192 | struct iio_buffer *buffer = indio_dev->buffer; |
193 | ||
194 | if (!buffer) | |
d2f0a48f LPC |
195 | return; |
196 | ||
ff3f7e04 | 197 | wake_up(&buffer->pollq); |
d2f0a48f LPC |
198 | } |
199 | ||
f79a9098 | 200 | void iio_buffer_init(struct iio_buffer *buffer) |
7026ea4b | 201 | { |
5ada4ea9 | 202 | INIT_LIST_HEAD(&buffer->demux_list); |
705ee2c9 | 203 | INIT_LIST_HEAD(&buffer->buffer_list); |
14555b14 | 204 | init_waitqueue_head(&buffer->pollq); |
9e69c935 | 205 | kref_init(&buffer->ref); |
4a605357 LPC |
206 | if (!buffer->watermark) |
207 | buffer->watermark = 1; | |
7026ea4b | 208 | } |
14555b14 | 209 | EXPORT_SYMBOL(iio_buffer_init); |
7026ea4b | 210 | |
9f466777 JC |
211 | /** |
212 | * iio_buffer_set_attrs - Set buffer specific attributes | |
213 | * @buffer: The buffer for which we are setting attributes | |
214 | * @attrs: Pointer to a null terminated list of pointers to attributes | |
215 | */ | |
216 | void iio_buffer_set_attrs(struct iio_buffer *buffer, | |
217 | const struct attribute **attrs) | |
218 | { | |
219 | buffer->attrs = attrs; | |
220 | } | |
221 | EXPORT_SYMBOL_GPL(iio_buffer_set_attrs); | |
222 | ||
1d892719 | 223 | static ssize_t iio_show_scan_index(struct device *dev, |
8d213f24 JC |
224 | struct device_attribute *attr, |
225 | char *buf) | |
1d892719 | 226 | { |
8d213f24 | 227 | return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index); |
1d892719 JC |
228 | } |
229 | ||
230 | static ssize_t iio_show_fixed_type(struct device *dev, | |
231 | struct device_attribute *attr, | |
232 | char *buf) | |
233 | { | |
234 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); | |
8310b86c JC |
235 | u8 type = this_attr->c->scan_type.endianness; |
236 | ||
237 | if (type == IIO_CPU) { | |
9d5d1153 JC |
238 | #ifdef __LITTLE_ENDIAN |
239 | type = IIO_LE; | |
240 | #else | |
241 | type = IIO_BE; | |
242 | #endif | |
8310b86c | 243 | } |
0ee8546a SP |
244 | if (this_attr->c->scan_type.repeat > 1) |
245 | return sprintf(buf, "%s:%c%d/%dX%d>>%u\n", | |
246 | iio_endian_prefix[type], | |
247 | this_attr->c->scan_type.sign, | |
248 | this_attr->c->scan_type.realbits, | |
249 | this_attr->c->scan_type.storagebits, | |
250 | this_attr->c->scan_type.repeat, | |
251 | this_attr->c->scan_type.shift); | |
252 | else | |
253 | return sprintf(buf, "%s:%c%d/%d>>%u\n", | |
8310b86c | 254 | iio_endian_prefix[type], |
1d892719 JC |
255 | this_attr->c->scan_type.sign, |
256 | this_attr->c->scan_type.realbits, | |
257 | this_attr->c->scan_type.storagebits, | |
258 | this_attr->c->scan_type.shift); | |
259 | } | |
260 | ||
8d213f24 JC |
261 | static ssize_t iio_scan_el_show(struct device *dev, |
262 | struct device_attribute *attr, | |
263 | char *buf) | |
264 | { | |
265 | int ret; | |
e53f5ac5 | 266 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
ff3f7e04 | 267 | struct iio_buffer *buffer = indio_dev->buffer; |
8d213f24 | 268 | |
2076a20f AB |
269 | /* Ensure ret is 0 or 1. */ |
270 | ret = !!test_bit(to_iio_dev_attr(attr)->address, | |
ff3f7e04 | 271 | buffer->scan_mask); |
5ada4ea9 | 272 | |
8d213f24 JC |
273 | return sprintf(buf, "%d\n", ret); |
274 | } | |
275 | ||
217a5cf0 LPC |
276 | /* Note NULL used as error indicator as it doesn't make sense. */ |
277 | static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks, | |
278 | unsigned int masklength, | |
1e1ec286 LPC |
279 | const unsigned long *mask, |
280 | bool strict) | |
217a5cf0 LPC |
281 | { |
282 | if (bitmap_empty(mask, masklength)) | |
283 | return NULL; | |
284 | while (*av_masks) { | |
1e1ec286 LPC |
285 | if (strict) { |
286 | if (bitmap_equal(mask, av_masks, masklength)) | |
287 | return av_masks; | |
288 | } else { | |
289 | if (bitmap_subset(mask, av_masks, masklength)) | |
290 | return av_masks; | |
291 | } | |
217a5cf0 LPC |
292 | av_masks += BITS_TO_LONGS(masklength); |
293 | } | |
294 | return NULL; | |
295 | } | |
296 | ||
297 | static bool iio_validate_scan_mask(struct iio_dev *indio_dev, | |
298 | const unsigned long *mask) | |
299 | { | |
300 | if (!indio_dev->setup_ops->validate_scan_mask) | |
301 | return true; | |
302 | ||
303 | return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask); | |
304 | } | |
305 | ||
306 | /** | |
307 | * iio_scan_mask_set() - set particular bit in the scan mask | |
308 | * @indio_dev: the iio device | |
309 | * @buffer: the buffer whose scan mask we are interested in | |
310 | * @bit: the bit to be set. | |
311 | * | |
312 | * Note that at this point we have no way of knowing what other | |
313 | * buffers might request, hence this code only verifies that the | |
314 | * individual buffers request is plausible. | |
315 | */ | |
316 | static int iio_scan_mask_set(struct iio_dev *indio_dev, | |
317 | struct iio_buffer *buffer, int bit) | |
318 | { | |
319 | const unsigned long *mask; | |
320 | unsigned long *trialmask; | |
321 | ||
ccd428e4 | 322 | trialmask = bitmap_zalloc(indio_dev->masklength, GFP_KERNEL); |
217a5cf0 LPC |
323 | if (trialmask == NULL) |
324 | return -ENOMEM; | |
325 | if (!indio_dev->masklength) { | |
231bfe53 | 326 | WARN(1, "Trying to set scanmask prior to registering buffer\n"); |
217a5cf0 LPC |
327 | goto err_invalid_mask; |
328 | } | |
329 | bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength); | |
330 | set_bit(bit, trialmask); | |
331 | ||
332 | if (!iio_validate_scan_mask(indio_dev, trialmask)) | |
333 | goto err_invalid_mask; | |
334 | ||
335 | if (indio_dev->available_scan_masks) { | |
336 | mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
337 | indio_dev->masklength, | |
1e1ec286 | 338 | trialmask, false); |
217a5cf0 LPC |
339 | if (!mask) |
340 | goto err_invalid_mask; | |
341 | } | |
342 | bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength); | |
343 | ||
3862828a | 344 | bitmap_free(trialmask); |
217a5cf0 LPC |
345 | |
346 | return 0; | |
347 | ||
348 | err_invalid_mask: | |
3862828a | 349 | bitmap_free(trialmask); |
217a5cf0 LPC |
350 | return -EINVAL; |
351 | } | |
352 | ||
14555b14 | 353 | static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit) |
8d213f24 | 354 | { |
14555b14 | 355 | clear_bit(bit, buffer->scan_mask); |
8d213f24 JC |
356 | return 0; |
357 | } | |
358 | ||
c2bf8d5f JC |
359 | static int iio_scan_mask_query(struct iio_dev *indio_dev, |
360 | struct iio_buffer *buffer, int bit) | |
361 | { | |
362 | if (bit > indio_dev->masklength) | |
363 | return -EINVAL; | |
364 | ||
365 | if (!buffer->scan_mask) | |
366 | return 0; | |
367 | ||
368 | /* Ensure return value is 0 or 1. */ | |
369 | return !!test_bit(bit, buffer->scan_mask); | |
370 | }; | |
371 | ||
8d213f24 JC |
372 | static ssize_t iio_scan_el_store(struct device *dev, |
373 | struct device_attribute *attr, | |
374 | const char *buf, | |
375 | size_t len) | |
376 | { | |
a714af27 | 377 | int ret; |
8d213f24 | 378 | bool state; |
e53f5ac5 | 379 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 380 | struct iio_buffer *buffer = indio_dev->buffer; |
8d213f24 JC |
381 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
382 | ||
a714af27 JC |
383 | ret = strtobool(buf, &state); |
384 | if (ret < 0) | |
385 | return ret; | |
8d213f24 | 386 | mutex_lock(&indio_dev->mlock); |
ff3f7e04 | 387 | if (iio_buffer_is_active(buffer)) { |
8d213f24 JC |
388 | ret = -EBUSY; |
389 | goto error_ret; | |
390 | } | |
f79a9098 | 391 | ret = iio_scan_mask_query(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
392 | if (ret < 0) |
393 | goto error_ret; | |
394 | if (!state && ret) { | |
14555b14 | 395 | ret = iio_scan_mask_clear(buffer, this_attr->address); |
8d213f24 JC |
396 | if (ret) |
397 | goto error_ret; | |
398 | } else if (state && !ret) { | |
f79a9098 | 399 | ret = iio_scan_mask_set(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
400 | if (ret) |
401 | goto error_ret; | |
402 | } | |
403 | ||
404 | error_ret: | |
405 | mutex_unlock(&indio_dev->mlock); | |
406 | ||
5a2a6e11 | 407 | return ret < 0 ? ret : len; |
8d213f24 JC |
408 | |
409 | } | |
410 | ||
411 | static ssize_t iio_scan_el_ts_show(struct device *dev, | |
412 | struct device_attribute *attr, | |
413 | char *buf) | |
414 | { | |
e53f5ac5 | 415 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
ff3f7e04 AA |
416 | struct iio_buffer *buffer = indio_dev->buffer; |
417 | ||
418 | return sprintf(buf, "%d\n", buffer->scan_timestamp); | |
8d213f24 JC |
419 | } |
420 | ||
421 | static ssize_t iio_scan_el_ts_store(struct device *dev, | |
422 | struct device_attribute *attr, | |
423 | const char *buf, | |
424 | size_t len) | |
425 | { | |
a714af27 | 426 | int ret; |
e53f5ac5 | 427 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
ff3f7e04 | 428 | struct iio_buffer *buffer = indio_dev->buffer; |
8d213f24 | 429 | bool state; |
1aa04278 | 430 | |
a714af27 JC |
431 | ret = strtobool(buf, &state); |
432 | if (ret < 0) | |
433 | return ret; | |
434 | ||
8d213f24 | 435 | mutex_lock(&indio_dev->mlock); |
ff3f7e04 | 436 | if (iio_buffer_is_active(buffer)) { |
8d213f24 JC |
437 | ret = -EBUSY; |
438 | goto error_ret; | |
439 | } | |
ff3f7e04 | 440 | buffer->scan_timestamp = state; |
8d213f24 JC |
441 | error_ret: |
442 | mutex_unlock(&indio_dev->mlock); | |
443 | ||
444 | return ret ? ret : len; | |
445 | } | |
446 | ||
14555b14 | 447 | static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev, |
ff3f7e04 | 448 | struct iio_buffer *buffer, |
14555b14 | 449 | const struct iio_chan_spec *chan) |
1d892719 | 450 | { |
26d25ae3 | 451 | int ret, attrcount = 0; |
1d892719 | 452 | |
26d25ae3 | 453 | ret = __iio_add_chan_devattr("index", |
1d892719 JC |
454 | chan, |
455 | &iio_show_scan_index, | |
456 | NULL, | |
457 | 0, | |
3704432f | 458 | IIO_SEPARATE, |
1aa04278 | 459 | &indio_dev->dev, |
14555b14 | 460 | &buffer->scan_el_dev_attr_list); |
1d892719 | 461 | if (ret) |
92825ff9 | 462 | return ret; |
26d25ae3 JC |
463 | attrcount++; |
464 | ret = __iio_add_chan_devattr("type", | |
1d892719 JC |
465 | chan, |
466 | &iio_show_fixed_type, | |
467 | NULL, | |
468 | 0, | |
469 | 0, | |
1aa04278 | 470 | &indio_dev->dev, |
14555b14 | 471 | &buffer->scan_el_dev_attr_list); |
1d892719 | 472 | if (ret) |
92825ff9 | 473 | return ret; |
26d25ae3 | 474 | attrcount++; |
a88b3ebc | 475 | if (chan->type != IIO_TIMESTAMP) |
26d25ae3 | 476 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
477 | chan, |
478 | &iio_scan_el_show, | |
479 | &iio_scan_el_store, | |
480 | chan->scan_index, | |
481 | 0, | |
1aa04278 | 482 | &indio_dev->dev, |
14555b14 | 483 | &buffer->scan_el_dev_attr_list); |
a88b3ebc | 484 | else |
26d25ae3 | 485 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
486 | chan, |
487 | &iio_scan_el_ts_show, | |
488 | &iio_scan_el_ts_store, | |
489 | chan->scan_index, | |
490 | 0, | |
1aa04278 | 491 | &indio_dev->dev, |
14555b14 | 492 | &buffer->scan_el_dev_attr_list); |
9572588c | 493 | if (ret) |
92825ff9 | 494 | return ret; |
26d25ae3 JC |
495 | attrcount++; |
496 | ret = attrcount; | |
1d892719 JC |
497 | return ret; |
498 | } | |
499 | ||
08e7e0ad LPC |
500 | static ssize_t iio_buffer_read_length(struct device *dev, |
501 | struct device_attribute *attr, | |
502 | char *buf) | |
7026ea4b | 503 | { |
e53f5ac5 | 504 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 505 | struct iio_buffer *buffer = indio_dev->buffer; |
7026ea4b | 506 | |
37495660 | 507 | return sprintf(buf, "%d\n", buffer->length); |
7026ea4b | 508 | } |
7026ea4b | 509 | |
08e7e0ad LPC |
510 | static ssize_t iio_buffer_write_length(struct device *dev, |
511 | struct device_attribute *attr, | |
512 | const char *buf, size_t len) | |
7026ea4b | 513 | { |
e53f5ac5 | 514 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 515 | struct iio_buffer *buffer = indio_dev->buffer; |
948ad205 LPC |
516 | unsigned int val; |
517 | int ret; | |
8d213f24 | 518 | |
948ad205 | 519 | ret = kstrtouint(buf, 10, &val); |
7026ea4b JC |
520 | if (ret) |
521 | return ret; | |
522 | ||
37495660 LPC |
523 | if (val == buffer->length) |
524 | return len; | |
7026ea4b | 525 | |
e38c79e0 | 526 | mutex_lock(&indio_dev->mlock); |
ff3f7e04 | 527 | if (iio_buffer_is_active(buffer)) { |
e38c79e0 LPC |
528 | ret = -EBUSY; |
529 | } else { | |
8d92db28 | 530 | buffer->access->set_length(buffer, val); |
e38c79e0 | 531 | ret = 0; |
7026ea4b | 532 | } |
37d34556 JC |
533 | if (ret) |
534 | goto out; | |
535 | if (buffer->length && buffer->length < buffer->watermark) | |
536 | buffer->watermark = buffer->length; | |
537 | out: | |
e38c79e0 | 538 | mutex_unlock(&indio_dev->mlock); |
7026ea4b | 539 | |
e38c79e0 | 540 | return ret ? ret : len; |
7026ea4b | 541 | } |
7026ea4b | 542 | |
08e7e0ad LPC |
543 | static ssize_t iio_buffer_show_enable(struct device *dev, |
544 | struct device_attribute *attr, | |
545 | char *buf) | |
7026ea4b | 546 | { |
e53f5ac5 | 547 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
ff3f7e04 AA |
548 | struct iio_buffer *buffer = indio_dev->buffer; |
549 | ||
550 | return sprintf(buf, "%d\n", iio_buffer_is_active(buffer)); | |
7026ea4b | 551 | } |
7026ea4b | 552 | |
182b4905 LPC |
553 | static unsigned int iio_storage_bytes_for_si(struct iio_dev *indio_dev, |
554 | unsigned int scan_index) | |
555 | { | |
556 | const struct iio_chan_spec *ch; | |
557 | unsigned int bytes; | |
558 | ||
559 | ch = iio_find_channel_from_si(indio_dev, scan_index); | |
560 | bytes = ch->scan_type.storagebits / 8; | |
561 | if (ch->scan_type.repeat > 1) | |
562 | bytes *= ch->scan_type.repeat; | |
563 | return bytes; | |
564 | } | |
565 | ||
566 | static unsigned int iio_storage_bytes_for_timestamp(struct iio_dev *indio_dev) | |
567 | { | |
568 | return iio_storage_bytes_for_si(indio_dev, | |
569 | indio_dev->scan_index_timestamp); | |
570 | } | |
571 | ||
183f4173 PM |
572 | static int iio_compute_scan_bytes(struct iio_dev *indio_dev, |
573 | const unsigned long *mask, bool timestamp) | |
959d2952 | 574 | { |
959d2952 | 575 | unsigned bytes = 0; |
883f6165 | 576 | int length, i, largest = 0; |
959d2952 JC |
577 | |
578 | /* How much space will the demuxed element take? */ | |
6b3b58ed | 579 | for_each_set_bit(i, mask, |
959d2952 | 580 | indio_dev->masklength) { |
182b4905 | 581 | length = iio_storage_bytes_for_si(indio_dev, i); |
959d2952 JC |
582 | bytes = ALIGN(bytes, length); |
583 | bytes += length; | |
883f6165 | 584 | largest = max(largest, length); |
959d2952 | 585 | } |
182b4905 | 586 | |
6b3b58ed | 587 | if (timestamp) { |
182b4905 | 588 | length = iio_storage_bytes_for_timestamp(indio_dev); |
959d2952 JC |
589 | bytes = ALIGN(bytes, length); |
590 | bytes += length; | |
883f6165 | 591 | largest = max(largest, length); |
959d2952 | 592 | } |
883f6165 LM |
593 | |
594 | bytes = ALIGN(bytes, largest); | |
6b3b58ed JC |
595 | return bytes; |
596 | } | |
597 | ||
9e69c935 LPC |
598 | static void iio_buffer_activate(struct iio_dev *indio_dev, |
599 | struct iio_buffer *buffer) | |
600 | { | |
601 | iio_buffer_get(buffer); | |
602 | list_add(&buffer->buffer_list, &indio_dev->buffer_list); | |
603 | } | |
604 | ||
605 | static void iio_buffer_deactivate(struct iio_buffer *buffer) | |
606 | { | |
607 | list_del_init(&buffer->buffer_list); | |
37d34556 | 608 | wake_up_interruptible(&buffer->pollq); |
9e69c935 LPC |
609 | iio_buffer_put(buffer); |
610 | } | |
611 | ||
1250186a LPC |
612 | static void iio_buffer_deactivate_all(struct iio_dev *indio_dev) |
613 | { | |
614 | struct iio_buffer *buffer, *_buffer; | |
615 | ||
616 | list_for_each_entry_safe(buffer, _buffer, | |
617 | &indio_dev->buffer_list, buffer_list) | |
618 | iio_buffer_deactivate(buffer); | |
619 | } | |
620 | ||
e18a2ad4 LPC |
621 | static int iio_buffer_enable(struct iio_buffer *buffer, |
622 | struct iio_dev *indio_dev) | |
623 | { | |
624 | if (!buffer->access->enable) | |
625 | return 0; | |
626 | return buffer->access->enable(buffer, indio_dev); | |
627 | } | |
628 | ||
629 | static int iio_buffer_disable(struct iio_buffer *buffer, | |
630 | struct iio_dev *indio_dev) | |
631 | { | |
632 | if (!buffer->access->disable) | |
633 | return 0; | |
634 | return buffer->access->disable(buffer, indio_dev); | |
635 | } | |
636 | ||
8e050996 LPC |
637 | static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev, |
638 | struct iio_buffer *buffer) | |
639 | { | |
640 | unsigned int bytes; | |
641 | ||
642 | if (!buffer->access->set_bytes_per_datum) | |
643 | return; | |
644 | ||
645 | bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask, | |
646 | buffer->scan_timestamp); | |
647 | ||
648 | buffer->access->set_bytes_per_datum(buffer, bytes); | |
649 | } | |
650 | ||
fcc1b2f5 LPC |
651 | static int iio_buffer_request_update(struct iio_dev *indio_dev, |
652 | struct iio_buffer *buffer) | |
653 | { | |
654 | int ret; | |
655 | ||
656 | iio_buffer_update_bytes_per_datum(indio_dev, buffer); | |
657 | if (buffer->access->request_update) { | |
658 | ret = buffer->access->request_update(buffer); | |
659 | if (ret) { | |
660 | dev_dbg(&indio_dev->dev, | |
661 | "Buffer not started: buffer parameter update failed (%d)\n", | |
662 | ret); | |
663 | return ret; | |
664 | } | |
665 | } | |
666 | ||
667 | return 0; | |
668 | } | |
669 | ||
248be5aa LPC |
670 | static void iio_free_scan_mask(struct iio_dev *indio_dev, |
671 | const unsigned long *mask) | |
672 | { | |
673 | /* If the mask is dynamically allocated free it, otherwise do nothing */ | |
674 | if (!indio_dev->available_scan_masks) | |
3862828a | 675 | bitmap_free(mask); |
248be5aa LPC |
676 | } |
677 | ||
6e509c4d LPC |
678 | struct iio_device_config { |
679 | unsigned int mode; | |
f0566c0c | 680 | unsigned int watermark; |
6e509c4d LPC |
681 | const unsigned long *scan_mask; |
682 | unsigned int scan_bytes; | |
683 | bool scan_timestamp; | |
684 | }; | |
685 | ||
686 | static int iio_verify_update(struct iio_dev *indio_dev, | |
687 | struct iio_buffer *insert_buffer, struct iio_buffer *remove_buffer, | |
688 | struct iio_device_config *config) | |
689 | { | |
690 | unsigned long *compound_mask; | |
691 | const unsigned long *scan_mask; | |
1e1ec286 | 692 | bool strict_scanmask = false; |
6e509c4d LPC |
693 | struct iio_buffer *buffer; |
694 | bool scan_timestamp; | |
225d59ad | 695 | unsigned int modes; |
6e509c4d | 696 | |
b7329249 LPC |
697 | if (insert_buffer && |
698 | bitmap_empty(insert_buffer->scan_mask, indio_dev->masklength)) { | |
699 | dev_dbg(&indio_dev->dev, | |
700 | "At least one scan element must be enabled first\n"); | |
701 | return -EINVAL; | |
702 | } | |
703 | ||
6e509c4d | 704 | memset(config, 0, sizeof(*config)); |
1bef2c1d | 705 | config->watermark = ~0; |
6e509c4d LPC |
706 | |
707 | /* | |
708 | * If there is just one buffer and we are removing it there is nothing | |
709 | * to verify. | |
710 | */ | |
711 | if (remove_buffer && !insert_buffer && | |
712 | list_is_singular(&indio_dev->buffer_list)) | |
713 | return 0; | |
714 | ||
225d59ad LPC |
715 | modes = indio_dev->modes; |
716 | ||
717 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
718 | if (buffer == remove_buffer) | |
719 | continue; | |
720 | modes &= buffer->access->modes; | |
f0566c0c | 721 | config->watermark = min(config->watermark, buffer->watermark); |
225d59ad LPC |
722 | } |
723 | ||
f0566c0c | 724 | if (insert_buffer) { |
225d59ad | 725 | modes &= insert_buffer->access->modes; |
f0566c0c LPC |
726 | config->watermark = min(config->watermark, |
727 | insert_buffer->watermark); | |
728 | } | |
225d59ad | 729 | |
6e509c4d | 730 | /* Definitely possible for devices to support both of these. */ |
225d59ad | 731 | if ((modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) { |
6e509c4d | 732 | config->mode = INDIO_BUFFER_TRIGGERED; |
225d59ad | 733 | } else if (modes & INDIO_BUFFER_HARDWARE) { |
1e1ec286 LPC |
734 | /* |
735 | * Keep things simple for now and only allow a single buffer to | |
736 | * be connected in hardware mode. | |
737 | */ | |
738 | if (insert_buffer && !list_empty(&indio_dev->buffer_list)) | |
739 | return -EINVAL; | |
6e509c4d | 740 | config->mode = INDIO_BUFFER_HARDWARE; |
1e1ec286 | 741 | strict_scanmask = true; |
225d59ad | 742 | } else if (modes & INDIO_BUFFER_SOFTWARE) { |
6e509c4d LPC |
743 | config->mode = INDIO_BUFFER_SOFTWARE; |
744 | } else { | |
745 | /* Can only occur on first buffer */ | |
746 | if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) | |
747 | dev_dbg(&indio_dev->dev, "Buffer not started: no trigger\n"); | |
748 | return -EINVAL; | |
749 | } | |
750 | ||
751 | /* What scan mask do we actually have? */ | |
3862828a | 752 | compound_mask = bitmap_zalloc(indio_dev->masklength, GFP_KERNEL); |
6e509c4d LPC |
753 | if (compound_mask == NULL) |
754 | return -ENOMEM; | |
755 | ||
756 | scan_timestamp = false; | |
757 | ||
758 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
759 | if (buffer == remove_buffer) | |
760 | continue; | |
761 | bitmap_or(compound_mask, compound_mask, buffer->scan_mask, | |
762 | indio_dev->masklength); | |
763 | scan_timestamp |= buffer->scan_timestamp; | |
764 | } | |
765 | ||
766 | if (insert_buffer) { | |
767 | bitmap_or(compound_mask, compound_mask, | |
768 | insert_buffer->scan_mask, indio_dev->masklength); | |
769 | scan_timestamp |= insert_buffer->scan_timestamp; | |
770 | } | |
771 | ||
772 | if (indio_dev->available_scan_masks) { | |
773 | scan_mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
774 | indio_dev->masklength, | |
1e1ec286 LPC |
775 | compound_mask, |
776 | strict_scanmask); | |
3862828a | 777 | bitmap_free(compound_mask); |
6e509c4d LPC |
778 | if (scan_mask == NULL) |
779 | return -EINVAL; | |
780 | } else { | |
781 | scan_mask = compound_mask; | |
782 | } | |
783 | ||
784 | config->scan_bytes = iio_compute_scan_bytes(indio_dev, | |
785 | scan_mask, scan_timestamp); | |
786 | config->scan_mask = scan_mask; | |
787 | config->scan_timestamp = scan_timestamp; | |
788 | ||
789 | return 0; | |
790 | } | |
791 | ||
78c9981f JC |
792 | /** |
793 | * struct iio_demux_table - table describing demux memcpy ops | |
794 | * @from: index to copy from | |
795 | * @to: index to copy to | |
796 | * @length: how many bytes to copy | |
797 | * @l: list head used for management | |
798 | */ | |
799 | struct iio_demux_table { | |
800 | unsigned from; | |
801 | unsigned to; | |
802 | unsigned length; | |
803 | struct list_head l; | |
804 | }; | |
805 | ||
806 | static void iio_buffer_demux_free(struct iio_buffer *buffer) | |
807 | { | |
808 | struct iio_demux_table *p, *q; | |
809 | list_for_each_entry_safe(p, q, &buffer->demux_list, l) { | |
810 | list_del(&p->l); | |
811 | kfree(p); | |
812 | } | |
813 | } | |
814 | ||
815 | static int iio_buffer_add_demux(struct iio_buffer *buffer, | |
816 | struct iio_demux_table **p, unsigned int in_loc, unsigned int out_loc, | |
817 | unsigned int length) | |
818 | { | |
819 | ||
820 | if (*p && (*p)->from + (*p)->length == in_loc && | |
821 | (*p)->to + (*p)->length == out_loc) { | |
822 | (*p)->length += length; | |
823 | } else { | |
824 | *p = kmalloc(sizeof(**p), GFP_KERNEL); | |
825 | if (*p == NULL) | |
826 | return -ENOMEM; | |
827 | (*p)->from = in_loc; | |
828 | (*p)->to = out_loc; | |
829 | (*p)->length = length; | |
830 | list_add_tail(&(*p)->l, &buffer->demux_list); | |
831 | } | |
832 | ||
833 | return 0; | |
834 | } | |
835 | ||
836 | static int iio_buffer_update_demux(struct iio_dev *indio_dev, | |
837 | struct iio_buffer *buffer) | |
838 | { | |
839 | int ret, in_ind = -1, out_ind, length; | |
840 | unsigned in_loc = 0, out_loc = 0; | |
841 | struct iio_demux_table *p = NULL; | |
842 | ||
843 | /* Clear out any old demux */ | |
844 | iio_buffer_demux_free(buffer); | |
845 | kfree(buffer->demux_bounce); | |
846 | buffer->demux_bounce = NULL; | |
847 | ||
848 | /* First work out which scan mode we will actually have */ | |
849 | if (bitmap_equal(indio_dev->active_scan_mask, | |
850 | buffer->scan_mask, | |
851 | indio_dev->masklength)) | |
852 | return 0; | |
853 | ||
854 | /* Now we have the two masks, work from least sig and build up sizes */ | |
855 | for_each_set_bit(out_ind, | |
856 | buffer->scan_mask, | |
857 | indio_dev->masklength) { | |
858 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
859 | indio_dev->masklength, | |
860 | in_ind + 1); | |
861 | while (in_ind != out_ind) { | |
862 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
863 | indio_dev->masklength, | |
864 | in_ind + 1); | |
865 | length = iio_storage_bytes_for_si(indio_dev, in_ind); | |
866 | /* Make sure we are aligned */ | |
867 | in_loc = roundup(in_loc, length) + length; | |
868 | } | |
869 | length = iio_storage_bytes_for_si(indio_dev, in_ind); | |
870 | out_loc = roundup(out_loc, length); | |
871 | in_loc = roundup(in_loc, length); | |
872 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); | |
873 | if (ret) | |
874 | goto error_clear_mux_table; | |
875 | out_loc += length; | |
876 | in_loc += length; | |
877 | } | |
878 | /* Relies on scan_timestamp being last */ | |
879 | if (buffer->scan_timestamp) { | |
880 | length = iio_storage_bytes_for_timestamp(indio_dev); | |
881 | out_loc = roundup(out_loc, length); | |
882 | in_loc = roundup(in_loc, length); | |
883 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); | |
884 | if (ret) | |
885 | goto error_clear_mux_table; | |
886 | out_loc += length; | |
887 | in_loc += length; | |
888 | } | |
889 | buffer->demux_bounce = kzalloc(out_loc, GFP_KERNEL); | |
890 | if (buffer->demux_bounce == NULL) { | |
891 | ret = -ENOMEM; | |
892 | goto error_clear_mux_table; | |
893 | } | |
894 | return 0; | |
895 | ||
896 | error_clear_mux_table: | |
897 | iio_buffer_demux_free(buffer); | |
898 | ||
899 | return ret; | |
900 | } | |
901 | ||
902 | static int iio_update_demux(struct iio_dev *indio_dev) | |
903 | { | |
904 | struct iio_buffer *buffer; | |
905 | int ret; | |
906 | ||
907 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
908 | ret = iio_buffer_update_demux(indio_dev, buffer); | |
909 | if (ret < 0) | |
910 | goto error_clear_mux_table; | |
911 | } | |
912 | return 0; | |
913 | ||
914 | error_clear_mux_table: | |
915 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) | |
916 | iio_buffer_demux_free(buffer); | |
917 | ||
918 | return ret; | |
919 | } | |
920 | ||
623d74e3 LPC |
921 | static int iio_enable_buffers(struct iio_dev *indio_dev, |
922 | struct iio_device_config *config) | |
6b3b58ed | 923 | { |
e18a2ad4 | 924 | struct iio_buffer *buffer; |
84b36ce5 | 925 | int ret; |
fcc1b2f5 | 926 | |
623d74e3 LPC |
927 | indio_dev->active_scan_mask = config->scan_mask; |
928 | indio_dev->scan_timestamp = config->scan_timestamp; | |
929 | indio_dev->scan_bytes = config->scan_bytes; | |
5cb1a548 | 930 | indio_dev->currentmode = config->mode; |
aff1eb4e | 931 | |
5ada4ea9 JC |
932 | iio_update_demux(indio_dev); |
933 | ||
84b36ce5 JC |
934 | /* Wind up again */ |
935 | if (indio_dev->setup_ops->preenable) { | |
936 | ret = indio_dev->setup_ops->preenable(indio_dev); | |
937 | if (ret) { | |
63223c5f | 938 | dev_dbg(&indio_dev->dev, |
bec1889d | 939 | "Buffer not started: buffer preenable failed (%d)\n", ret); |
623d74e3 | 940 | goto err_undo_config; |
84b36ce5 JC |
941 | } |
942 | } | |
6e509c4d | 943 | |
84b36ce5 JC |
944 | if (indio_dev->info->update_scan_mode) { |
945 | ret = indio_dev->info | |
5ada4ea9 JC |
946 | ->update_scan_mode(indio_dev, |
947 | indio_dev->active_scan_mask); | |
84b36ce5 | 948 | if (ret < 0) { |
63223c5f LPC |
949 | dev_dbg(&indio_dev->dev, |
950 | "Buffer not started: update scan mode failed (%d)\n", | |
951 | ret); | |
623d74e3 | 952 | goto err_run_postdisable; |
84b36ce5 JC |
953 | } |
954 | } | |
6e509c4d | 955 | |
f0566c0c LPC |
956 | if (indio_dev->info->hwfifo_set_watermark) |
957 | indio_dev->info->hwfifo_set_watermark(indio_dev, | |
958 | config->watermark); | |
959 | ||
e18a2ad4 LPC |
960 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { |
961 | ret = iio_buffer_enable(buffer, indio_dev); | |
962 | if (ret) | |
963 | goto err_disable_buffers; | |
964 | } | |
965 | ||
84b36ce5 JC |
966 | if (indio_dev->setup_ops->postenable) { |
967 | ret = indio_dev->setup_ops->postenable(indio_dev); | |
968 | if (ret) { | |
63223c5f | 969 | dev_dbg(&indio_dev->dev, |
bec1889d | 970 | "Buffer not started: postenable failed (%d)\n", ret); |
e18a2ad4 | 971 | goto err_disable_buffers; |
84b36ce5 JC |
972 | } |
973 | } | |
974 | ||
6e509c4d | 975 | return 0; |
84b36ce5 | 976 | |
e18a2ad4 LPC |
977 | err_disable_buffers: |
978 | list_for_each_entry_continue_reverse(buffer, &indio_dev->buffer_list, | |
979 | buffer_list) | |
980 | iio_buffer_disable(buffer, indio_dev); | |
623d74e3 | 981 | err_run_postdisable: |
84b36ce5 JC |
982 | if (indio_dev->setup_ops->postdisable) |
983 | indio_dev->setup_ops->postdisable(indio_dev); | |
623d74e3 | 984 | err_undo_config: |
5cb1a548 | 985 | indio_dev->currentmode = INDIO_DIRECT_MODE; |
623d74e3 LPC |
986 | indio_dev->active_scan_mask = NULL; |
987 | ||
84b36ce5 | 988 | return ret; |
623d74e3 LPC |
989 | } |
990 | ||
991 | static int iio_disable_buffers(struct iio_dev *indio_dev) | |
992 | { | |
e18a2ad4 | 993 | struct iio_buffer *buffer; |
1250186a LPC |
994 | int ret = 0; |
995 | int ret2; | |
623d74e3 LPC |
996 | |
997 | /* Wind down existing buffers - iff there are any */ | |
998 | if (list_empty(&indio_dev->buffer_list)) | |
999 | return 0; | |
1000 | ||
1250186a LPC |
1001 | /* |
1002 | * If things go wrong at some step in disable we still need to continue | |
1003 | * to perform the other steps, otherwise we leave the device in a | |
1004 | * inconsistent state. We return the error code for the first error we | |
1005 | * encountered. | |
1006 | */ | |
1007 | ||
623d74e3 | 1008 | if (indio_dev->setup_ops->predisable) { |
1250186a LPC |
1009 | ret2 = indio_dev->setup_ops->predisable(indio_dev); |
1010 | if (ret2 && !ret) | |
1011 | ret = ret2; | |
623d74e3 | 1012 | } |
e18a2ad4 LPC |
1013 | |
1014 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
1015 | ret2 = iio_buffer_disable(buffer, indio_dev); | |
1016 | if (ret2 && !ret) | |
1017 | ret = ret2; | |
1018 | } | |
623d74e3 | 1019 | |
623d74e3 | 1020 | if (indio_dev->setup_ops->postdisable) { |
1250186a LPC |
1021 | ret2 = indio_dev->setup_ops->postdisable(indio_dev); |
1022 | if (ret2 && !ret) | |
1023 | ret = ret2; | |
623d74e3 LPC |
1024 | } |
1025 | ||
1250186a LPC |
1026 | iio_free_scan_mask(indio_dev, indio_dev->active_scan_mask); |
1027 | indio_dev->active_scan_mask = NULL; | |
5cb1a548 | 1028 | indio_dev->currentmode = INDIO_DIRECT_MODE; |
1250186a LPC |
1029 | |
1030 | return ret; | |
623d74e3 LPC |
1031 | } |
1032 | ||
1033 | static int __iio_update_buffers(struct iio_dev *indio_dev, | |
1034 | struct iio_buffer *insert_buffer, | |
1035 | struct iio_buffer *remove_buffer) | |
1036 | { | |
623d74e3 | 1037 | struct iio_device_config new_config; |
1250186a | 1038 | int ret; |
623d74e3 LPC |
1039 | |
1040 | ret = iio_verify_update(indio_dev, insert_buffer, remove_buffer, | |
1041 | &new_config); | |
1042 | if (ret) | |
1043 | return ret; | |
1044 | ||
1045 | if (insert_buffer) { | |
1046 | ret = iio_buffer_request_update(indio_dev, insert_buffer); | |
1047 | if (ret) | |
1048 | goto err_free_config; | |
1049 | } | |
1050 | ||
623d74e3 | 1051 | ret = iio_disable_buffers(indio_dev); |
1250186a LPC |
1052 | if (ret) |
1053 | goto err_deactivate_all; | |
623d74e3 LPC |
1054 | |
1055 | if (remove_buffer) | |
1056 | iio_buffer_deactivate(remove_buffer); | |
1057 | if (insert_buffer) | |
1058 | iio_buffer_activate(indio_dev, insert_buffer); | |
1059 | ||
1060 | /* If no buffers in list, we are done */ | |
1250186a | 1061 | if (list_empty(&indio_dev->buffer_list)) |
623d74e3 | 1062 | return 0; |
623d74e3 LPC |
1063 | |
1064 | ret = iio_enable_buffers(indio_dev, &new_config); | |
1250186a LPC |
1065 | if (ret) |
1066 | goto err_deactivate_all; | |
623d74e3 | 1067 | |
623d74e3 | 1068 | return 0; |
6e509c4d | 1069 | |
1250186a LPC |
1070 | err_deactivate_all: |
1071 | /* | |
1072 | * We've already verified that the config is valid earlier. If things go | |
1073 | * wrong in either enable or disable the most likely reason is an IO | |
1074 | * error from the device. In this case there is no good recovery | |
1075 | * strategy. Just make sure to disable everything and leave the device | |
1076 | * in a sane state. With a bit of luck the device might come back to | |
1077 | * life again later and userspace can try again. | |
1078 | */ | |
1079 | iio_buffer_deactivate_all(indio_dev); | |
1080 | ||
6e509c4d LPC |
1081 | err_free_config: |
1082 | iio_free_scan_mask(indio_dev, new_config.scan_mask); | |
1083 | return ret; | |
84b36ce5 | 1084 | } |
a9519456 LPC |
1085 | |
1086 | int iio_update_buffers(struct iio_dev *indio_dev, | |
1087 | struct iio_buffer *insert_buffer, | |
1088 | struct iio_buffer *remove_buffer) | |
1089 | { | |
1090 | int ret; | |
1091 | ||
3909fab5 LPC |
1092 | if (insert_buffer == remove_buffer) |
1093 | return 0; | |
1094 | ||
a9519456 LPC |
1095 | mutex_lock(&indio_dev->info_exist_lock); |
1096 | mutex_lock(&indio_dev->mlock); | |
1097 | ||
3909fab5 LPC |
1098 | if (insert_buffer && iio_buffer_is_active(insert_buffer)) |
1099 | insert_buffer = NULL; | |
1100 | ||
1101 | if (remove_buffer && !iio_buffer_is_active(remove_buffer)) | |
1102 | remove_buffer = NULL; | |
1103 | ||
1104 | if (!insert_buffer && !remove_buffer) { | |
1105 | ret = 0; | |
1106 | goto out_unlock; | |
1107 | } | |
1108 | ||
a9519456 LPC |
1109 | if (indio_dev->info == NULL) { |
1110 | ret = -ENODEV; | |
1111 | goto out_unlock; | |
1112 | } | |
1113 | ||
1114 | ret = __iio_update_buffers(indio_dev, insert_buffer, remove_buffer); | |
1115 | ||
1116 | out_unlock: | |
1117 | mutex_unlock(&indio_dev->mlock); | |
1118 | mutex_unlock(&indio_dev->info_exist_lock); | |
1119 | ||
1120 | return ret; | |
1121 | } | |
84b36ce5 JC |
1122 | EXPORT_SYMBOL_GPL(iio_update_buffers); |
1123 | ||
623d74e3 LPC |
1124 | void iio_disable_all_buffers(struct iio_dev *indio_dev) |
1125 | { | |
623d74e3 | 1126 | iio_disable_buffers(indio_dev); |
1250186a | 1127 | iio_buffer_deactivate_all(indio_dev); |
623d74e3 LPC |
1128 | } |
1129 | ||
08e7e0ad LPC |
1130 | static ssize_t iio_buffer_store_enable(struct device *dev, |
1131 | struct device_attribute *attr, | |
1132 | const char *buf, | |
1133 | size_t len) | |
84b36ce5 JC |
1134 | { |
1135 | int ret; | |
1136 | bool requested_state; | |
1137 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
ff3f7e04 | 1138 | struct iio_buffer *buffer = indio_dev->buffer; |
84b36ce5 JC |
1139 | bool inlist; |
1140 | ||
1141 | ret = strtobool(buf, &requested_state); | |
1142 | if (ret < 0) | |
1143 | return ret; | |
1144 | ||
1145 | mutex_lock(&indio_dev->mlock); | |
1146 | ||
1147 | /* Find out if it is in the list */ | |
ff3f7e04 | 1148 | inlist = iio_buffer_is_active(buffer); |
84b36ce5 JC |
1149 | /* Already in desired state */ |
1150 | if (inlist == requested_state) | |
1151 | goto done; | |
1152 | ||
1153 | if (requested_state) | |
ff3f7e04 | 1154 | ret = __iio_update_buffers(indio_dev, buffer, NULL); |
84b36ce5 | 1155 | else |
ff3f7e04 | 1156 | ret = __iio_update_buffers(indio_dev, NULL, buffer); |
84b36ce5 | 1157 | |
84b36ce5 JC |
1158 | done: |
1159 | mutex_unlock(&indio_dev->mlock); | |
1160 | return (ret < 0) ? ret : len; | |
1161 | } | |
84b36ce5 | 1162 | |
d967cb6b LPC |
1163 | static const char * const iio_scan_elements_group_name = "scan_elements"; |
1164 | ||
37d34556 JC |
1165 | static ssize_t iio_buffer_show_watermark(struct device *dev, |
1166 | struct device_attribute *attr, | |
1167 | char *buf) | |
1168 | { | |
1169 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1170 | struct iio_buffer *buffer = indio_dev->buffer; | |
1171 | ||
1172 | return sprintf(buf, "%u\n", buffer->watermark); | |
1173 | } | |
1174 | ||
1175 | static ssize_t iio_buffer_store_watermark(struct device *dev, | |
1176 | struct device_attribute *attr, | |
1177 | const char *buf, | |
1178 | size_t len) | |
1179 | { | |
1180 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1181 | struct iio_buffer *buffer = indio_dev->buffer; | |
1182 | unsigned int val; | |
1183 | int ret; | |
1184 | ||
1185 | ret = kstrtouint(buf, 10, &val); | |
1186 | if (ret) | |
1187 | return ret; | |
1188 | if (!val) | |
1189 | return -EINVAL; | |
1190 | ||
1191 | mutex_lock(&indio_dev->mlock); | |
1192 | ||
1193 | if (val > buffer->length) { | |
1194 | ret = -EINVAL; | |
1195 | goto out; | |
1196 | } | |
1197 | ||
ff3f7e04 | 1198 | if (iio_buffer_is_active(buffer)) { |
37d34556 JC |
1199 | ret = -EBUSY; |
1200 | goto out; | |
1201 | } | |
1202 | ||
1203 | buffer->watermark = val; | |
1204 | out: | |
1205 | mutex_unlock(&indio_dev->mlock); | |
1206 | ||
1207 | return ret ? ret : len; | |
1208 | } | |
1209 | ||
350f6c75 MF |
1210 | static ssize_t iio_dma_show_data_available(struct device *dev, |
1211 | struct device_attribute *attr, | |
1212 | char *buf) | |
1213 | { | |
1214 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
ff3f7e04 | 1215 | struct iio_buffer *buffer = indio_dev->buffer; |
350f6c75 | 1216 | |
ff3f7e04 | 1217 | return sprintf(buf, "%zu\n", iio_buffer_data_available(buffer)); |
350f6c75 MF |
1218 | } |
1219 | ||
08e7e0ad LPC |
1220 | static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length, |
1221 | iio_buffer_write_length); | |
8d92db28 LPC |
1222 | static struct device_attribute dev_attr_length_ro = __ATTR(length, |
1223 | S_IRUGO, iio_buffer_read_length, NULL); | |
08e7e0ad LPC |
1224 | static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, |
1225 | iio_buffer_show_enable, iio_buffer_store_enable); | |
37d34556 JC |
1226 | static DEVICE_ATTR(watermark, S_IRUGO | S_IWUSR, |
1227 | iio_buffer_show_watermark, iio_buffer_store_watermark); | |
b440655b LPC |
1228 | static struct device_attribute dev_attr_watermark_ro = __ATTR(watermark, |
1229 | S_IRUGO, iio_buffer_show_watermark, NULL); | |
350f6c75 MF |
1230 | static DEVICE_ATTR(data_available, S_IRUGO, |
1231 | iio_dma_show_data_available, NULL); | |
08e7e0ad | 1232 | |
6da9b382 OP |
1233 | static struct attribute *iio_buffer_attrs[] = { |
1234 | &dev_attr_length.attr, | |
1235 | &dev_attr_enable.attr, | |
37d34556 | 1236 | &dev_attr_watermark.attr, |
350f6c75 | 1237 | &dev_attr_data_available.attr, |
6da9b382 OP |
1238 | }; |
1239 | ||
d967cb6b LPC |
1240 | int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev) |
1241 | { | |
1242 | struct iio_dev_attr *p; | |
1243 | struct attribute **attr; | |
1244 | struct iio_buffer *buffer = indio_dev->buffer; | |
96144d43 | 1245 | int ret, i, attrn, attrcount; |
d967cb6b LPC |
1246 | const struct iio_chan_spec *channels; |
1247 | ||
629bc023 LPC |
1248 | channels = indio_dev->channels; |
1249 | if (channels) { | |
1250 | int ml = indio_dev->masklength; | |
1251 | ||
1252 | for (i = 0; i < indio_dev->num_channels; i++) | |
1253 | ml = max(ml, channels[i].scan_index + 1); | |
1254 | indio_dev->masklength = ml; | |
1255 | } | |
1256 | ||
d967cb6b LPC |
1257 | if (!buffer) |
1258 | return 0; | |
1259 | ||
08e7e0ad LPC |
1260 | attrcount = 0; |
1261 | if (buffer->attrs) { | |
1262 | while (buffer->attrs[attrcount] != NULL) | |
1263 | attrcount++; | |
1264 | } | |
1265 | ||
6da9b382 OP |
1266 | attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, |
1267 | sizeof(struct attribute *), GFP_KERNEL); | |
1268 | if (!attr) | |
08e7e0ad LPC |
1269 | return -ENOMEM; |
1270 | ||
6da9b382 OP |
1271 | memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); |
1272 | if (!buffer->access->set_length) | |
1273 | attr[0] = &dev_attr_length_ro.attr; | |
1274 | ||
b440655b LPC |
1275 | if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) |
1276 | attr[2] = &dev_attr_watermark_ro.attr; | |
1277 | ||
08e7e0ad | 1278 | if (buffer->attrs) |
6da9b382 OP |
1279 | memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, |
1280 | sizeof(struct attribute *) * attrcount); | |
1281 | ||
1282 | attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; | |
1283 | ||
1284 | buffer->buffer_group.name = "buffer"; | |
1285 | buffer->buffer_group.attrs = attr; | |
08e7e0ad LPC |
1286 | |
1287 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->buffer_group; | |
1288 | ||
96144d43 | 1289 | attrcount = 0; |
d967cb6b LPC |
1290 | INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); |
1291 | channels = indio_dev->channels; | |
1292 | if (channels) { | |
1293 | /* new magic */ | |
1294 | for (i = 0; i < indio_dev->num_channels; i++) { | |
1295 | if (channels[i].scan_index < 0) | |
1296 | continue; | |
1297 | ||
ff3f7e04 | 1298 | ret = iio_buffer_add_channel_sysfs(indio_dev, buffer, |
d967cb6b LPC |
1299 | &channels[i]); |
1300 | if (ret < 0) | |
1301 | goto error_cleanup_dynamic; | |
1302 | attrcount += ret; | |
1303 | if (channels[i].type == IIO_TIMESTAMP) | |
1304 | indio_dev->scan_index_timestamp = | |
1305 | channels[i].scan_index; | |
1306 | } | |
1307 | if (indio_dev->masklength && buffer->scan_mask == NULL) { | |
3862828a AS |
1308 | buffer->scan_mask = bitmap_zalloc(indio_dev->masklength, |
1309 | GFP_KERNEL); | |
d967cb6b LPC |
1310 | if (buffer->scan_mask == NULL) { |
1311 | ret = -ENOMEM; | |
1312 | goto error_cleanup_dynamic; | |
1313 | } | |
1314 | } | |
1315 | } | |
1316 | ||
1317 | buffer->scan_el_group.name = iio_scan_elements_group_name; | |
1318 | ||
1319 | buffer->scan_el_group.attrs = kcalloc(attrcount + 1, | |
1320 | sizeof(buffer->scan_el_group.attrs[0]), | |
1321 | GFP_KERNEL); | |
1322 | if (buffer->scan_el_group.attrs == NULL) { | |
1323 | ret = -ENOMEM; | |
1324 | goto error_free_scan_mask; | |
1325 | } | |
96144d43 | 1326 | attrn = 0; |
d967cb6b LPC |
1327 | |
1328 | list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l) | |
1329 | buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr; | |
1330 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group; | |
1331 | ||
1332 | return 0; | |
1333 | ||
1334 | error_free_scan_mask: | |
3862828a | 1335 | bitmap_free(buffer->scan_mask); |
d967cb6b LPC |
1336 | error_cleanup_dynamic: |
1337 | iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); | |
ff3f7e04 | 1338 | kfree(buffer->buffer_group.attrs); |
d967cb6b LPC |
1339 | |
1340 | return ret; | |
1341 | } | |
1342 | ||
1343 | void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev) | |
1344 | { | |
ff3f7e04 AA |
1345 | struct iio_buffer *buffer = indio_dev->buffer; |
1346 | ||
1347 | if (!buffer) | |
d967cb6b LPC |
1348 | return; |
1349 | ||
ff3f7e04 AA |
1350 | bitmap_free(buffer->scan_mask); |
1351 | kfree(buffer->buffer_group.attrs); | |
1352 | kfree(buffer->scan_el_group.attrs); | |
1353 | iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); | |
d967cb6b LPC |
1354 | } |
1355 | ||
81636632 LPC |
1356 | /** |
1357 | * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected | |
1358 | * @indio_dev: the iio device | |
1359 | * @mask: scan mask to be checked | |
1360 | * | |
1361 | * Return true if exactly one bit is set in the scan mask, false otherwise. It | |
1362 | * can be used for devices where only one channel can be active for sampling at | |
1363 | * a time. | |
1364 | */ | |
1365 | bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, | |
1366 | const unsigned long *mask) | |
1367 | { | |
1368 | return bitmap_weight(mask, indio_dev->masklength) == 1; | |
1369 | } | |
1370 | EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot); | |
1371 | ||
5d65d920 LPC |
1372 | static const void *iio_demux(struct iio_buffer *buffer, |
1373 | const void *datain) | |
5ada4ea9 JC |
1374 | { |
1375 | struct iio_demux_table *t; | |
1376 | ||
1377 | if (list_empty(&buffer->demux_list)) | |
1378 | return datain; | |
1379 | list_for_each_entry(t, &buffer->demux_list, l) | |
1380 | memcpy(buffer->demux_bounce + t->to, | |
1381 | datain + t->from, t->length); | |
1382 | ||
1383 | return buffer->demux_bounce; | |
1384 | } | |
1385 | ||
5d65d920 | 1386 | static int iio_push_to_buffer(struct iio_buffer *buffer, const void *data) |
5ada4ea9 | 1387 | { |
5d65d920 | 1388 | const void *dataout = iio_demux(buffer, data); |
37d34556 JC |
1389 | int ret; |
1390 | ||
1391 | ret = buffer->access->store_to(buffer, dataout); | |
1392 | if (ret) | |
1393 | return ret; | |
5ada4ea9 | 1394 | |
37d34556 JC |
1395 | /* |
1396 | * We can't just test for watermark to decide if we wake the poll queue | |
1397 | * because read may request less samples than the watermark. | |
1398 | */ | |
a9a08845 | 1399 | wake_up_interruptible_poll(&buffer->pollq, EPOLLIN | EPOLLRDNORM); |
37d34556 | 1400 | return 0; |
5ada4ea9 | 1401 | } |
5ada4ea9 | 1402 | |
315a19ec JC |
1403 | /** |
1404 | * iio_push_to_buffers() - push to a registered buffer. | |
1405 | * @indio_dev: iio_dev structure for device. | |
1406 | * @data: Full scan. | |
1407 | */ | |
5d65d920 | 1408 | int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data) |
84b36ce5 JC |
1409 | { |
1410 | int ret; | |
1411 | struct iio_buffer *buf; | |
1412 | ||
1413 | list_for_each_entry(buf, &indio_dev->buffer_list, buffer_list) { | |
1414 | ret = iio_push_to_buffer(buf, data); | |
1415 | if (ret < 0) | |
1416 | return ret; | |
1417 | } | |
1418 | ||
1419 | return 0; | |
1420 | } | |
1421 | EXPORT_SYMBOL_GPL(iio_push_to_buffers); | |
1422 | ||
9e69c935 LPC |
1423 | /** |
1424 | * iio_buffer_release() - Free a buffer's resources | |
1425 | * @ref: Pointer to the kref embedded in the iio_buffer struct | |
1426 | * | |
1427 | * This function is called when the last reference to the buffer has been | |
1428 | * dropped. It will typically free all resources allocated by the buffer. Do not | |
1429 | * call this function manually, always use iio_buffer_put() when done using a | |
1430 | * buffer. | |
1431 | */ | |
1432 | static void iio_buffer_release(struct kref *ref) | |
1433 | { | |
1434 | struct iio_buffer *buffer = container_of(ref, struct iio_buffer, ref); | |
1435 | ||
1436 | buffer->access->release(buffer); | |
1437 | } | |
1438 | ||
1439 | /** | |
1440 | * iio_buffer_get() - Grab a reference to the buffer | |
1441 | * @buffer: The buffer to grab a reference for, may be NULL | |
1442 | * | |
1443 | * Returns the pointer to the buffer that was passed into the function. | |
1444 | */ | |
1445 | struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer) | |
1446 | { | |
1447 | if (buffer) | |
1448 | kref_get(&buffer->ref); | |
1449 | ||
1450 | return buffer; | |
1451 | } | |
1452 | EXPORT_SYMBOL_GPL(iio_buffer_get); | |
1453 | ||
1454 | /** | |
1455 | * iio_buffer_put() - Release the reference to the buffer | |
1456 | * @buffer: The buffer to release the reference for, may be NULL | |
1457 | */ | |
1458 | void iio_buffer_put(struct iio_buffer *buffer) | |
1459 | { | |
1460 | if (buffer) | |
1461 | kref_put(&buffer->ref, iio_buffer_release); | |
1462 | } | |
1463 | EXPORT_SYMBOL_GPL(iio_buffer_put); | |
2b827ad5 JC |
1464 | |
1465 | /** | |
1466 | * iio_device_attach_buffer - Attach a buffer to a IIO device | |
1467 | * @indio_dev: The device the buffer should be attached to | |
1468 | * @buffer: The buffer to attach to the device | |
1469 | * | |
1470 | * This function attaches a buffer to a IIO device. The buffer stays attached to | |
1471 | * the device until the device is freed. The function should only be called at | |
1472 | * most once per device. | |
1473 | */ | |
1474 | void iio_device_attach_buffer(struct iio_dev *indio_dev, | |
1475 | struct iio_buffer *buffer) | |
1476 | { | |
1477 | indio_dev->buffer = iio_buffer_get(buffer); | |
1478 | } | |
1479 | EXPORT_SYMBOL_GPL(iio_device_attach_buffer); |