Commit | Line | Data |
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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 | /** |
14555b14 | 90 | * iio_buffer_read_first_n_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 | **/ |
14555b14 JC |
102 | ssize_t iio_buffer_read_first_n_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 | ||
96e00f11 | 115 | if (!rb || !rb->access->read_first_n) |
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 LPC |
149 | |
150 | ret = rb->access->read_first_n(rb, n, buf); | |
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 | { | |
192 | if (!indio_dev->buffer) | |
193 | return; | |
194 | ||
195 | wake_up(&indio_dev->buffer->pollq); | |
196 | } | |
197 | ||
f79a9098 | 198 | void iio_buffer_init(struct iio_buffer *buffer) |
7026ea4b | 199 | { |
5ada4ea9 | 200 | INIT_LIST_HEAD(&buffer->demux_list); |
705ee2c9 | 201 | INIT_LIST_HEAD(&buffer->buffer_list); |
14555b14 | 202 | init_waitqueue_head(&buffer->pollq); |
9e69c935 | 203 | kref_init(&buffer->ref); |
4a605357 LPC |
204 | if (!buffer->watermark) |
205 | buffer->watermark = 1; | |
7026ea4b | 206 | } |
14555b14 | 207 | EXPORT_SYMBOL(iio_buffer_init); |
7026ea4b | 208 | |
9f466777 JC |
209 | /** |
210 | * iio_buffer_set_attrs - Set buffer specific attributes | |
211 | * @buffer: The buffer for which we are setting attributes | |
212 | * @attrs: Pointer to a null terminated list of pointers to attributes | |
213 | */ | |
214 | void iio_buffer_set_attrs(struct iio_buffer *buffer, | |
215 | const struct attribute **attrs) | |
216 | { | |
217 | buffer->attrs = attrs; | |
218 | } | |
219 | EXPORT_SYMBOL_GPL(iio_buffer_set_attrs); | |
220 | ||
1d892719 | 221 | static ssize_t iio_show_scan_index(struct device *dev, |
8d213f24 JC |
222 | struct device_attribute *attr, |
223 | char *buf) | |
1d892719 | 224 | { |
8d213f24 | 225 | return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index); |
1d892719 JC |
226 | } |
227 | ||
228 | static ssize_t iio_show_fixed_type(struct device *dev, | |
229 | struct device_attribute *attr, | |
230 | char *buf) | |
231 | { | |
232 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); | |
8310b86c JC |
233 | u8 type = this_attr->c->scan_type.endianness; |
234 | ||
235 | if (type == IIO_CPU) { | |
9d5d1153 JC |
236 | #ifdef __LITTLE_ENDIAN |
237 | type = IIO_LE; | |
238 | #else | |
239 | type = IIO_BE; | |
240 | #endif | |
8310b86c | 241 | } |
0ee8546a SP |
242 | if (this_attr->c->scan_type.repeat > 1) |
243 | return sprintf(buf, "%s:%c%d/%dX%d>>%u\n", | |
244 | iio_endian_prefix[type], | |
245 | this_attr->c->scan_type.sign, | |
246 | this_attr->c->scan_type.realbits, | |
247 | this_attr->c->scan_type.storagebits, | |
248 | this_attr->c->scan_type.repeat, | |
249 | this_attr->c->scan_type.shift); | |
250 | else | |
251 | return sprintf(buf, "%s:%c%d/%d>>%u\n", | |
8310b86c | 252 | iio_endian_prefix[type], |
1d892719 JC |
253 | this_attr->c->scan_type.sign, |
254 | this_attr->c->scan_type.realbits, | |
255 | this_attr->c->scan_type.storagebits, | |
256 | this_attr->c->scan_type.shift); | |
257 | } | |
258 | ||
8d213f24 JC |
259 | static ssize_t iio_scan_el_show(struct device *dev, |
260 | struct device_attribute *attr, | |
261 | char *buf) | |
262 | { | |
263 | int ret; | |
e53f5ac5 | 264 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 265 | |
2076a20f AB |
266 | /* Ensure ret is 0 or 1. */ |
267 | ret = !!test_bit(to_iio_dev_attr(attr)->address, | |
5ada4ea9 JC |
268 | indio_dev->buffer->scan_mask); |
269 | ||
8d213f24 JC |
270 | return sprintf(buf, "%d\n", ret); |
271 | } | |
272 | ||
217a5cf0 LPC |
273 | /* Note NULL used as error indicator as it doesn't make sense. */ |
274 | static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks, | |
275 | unsigned int masklength, | |
1e1ec286 LPC |
276 | const unsigned long *mask, |
277 | bool strict) | |
217a5cf0 LPC |
278 | { |
279 | if (bitmap_empty(mask, masklength)) | |
280 | return NULL; | |
281 | while (*av_masks) { | |
1e1ec286 LPC |
282 | if (strict) { |
283 | if (bitmap_equal(mask, av_masks, masklength)) | |
284 | return av_masks; | |
285 | } else { | |
286 | if (bitmap_subset(mask, av_masks, masklength)) | |
287 | return av_masks; | |
288 | } | |
217a5cf0 LPC |
289 | av_masks += BITS_TO_LONGS(masklength); |
290 | } | |
291 | return NULL; | |
292 | } | |
293 | ||
294 | static bool iio_validate_scan_mask(struct iio_dev *indio_dev, | |
295 | const unsigned long *mask) | |
296 | { | |
297 | if (!indio_dev->setup_ops->validate_scan_mask) | |
298 | return true; | |
299 | ||
300 | return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask); | |
301 | } | |
302 | ||
303 | /** | |
304 | * iio_scan_mask_set() - set particular bit in the scan mask | |
305 | * @indio_dev: the iio device | |
306 | * @buffer: the buffer whose scan mask we are interested in | |
307 | * @bit: the bit to be set. | |
308 | * | |
309 | * Note that at this point we have no way of knowing what other | |
310 | * buffers might request, hence this code only verifies that the | |
311 | * individual buffers request is plausible. | |
312 | */ | |
313 | static int iio_scan_mask_set(struct iio_dev *indio_dev, | |
314 | struct iio_buffer *buffer, int bit) | |
315 | { | |
316 | const unsigned long *mask; | |
317 | unsigned long *trialmask; | |
318 | ||
20ea39ef LPC |
319 | trialmask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), |
320 | sizeof(*trialmask), GFP_KERNEL); | |
217a5cf0 LPC |
321 | if (trialmask == NULL) |
322 | return -ENOMEM; | |
323 | if (!indio_dev->masklength) { | |
231bfe53 | 324 | WARN(1, "Trying to set scanmask prior to registering buffer\n"); |
217a5cf0 LPC |
325 | goto err_invalid_mask; |
326 | } | |
327 | bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength); | |
328 | set_bit(bit, trialmask); | |
329 | ||
330 | if (!iio_validate_scan_mask(indio_dev, trialmask)) | |
331 | goto err_invalid_mask; | |
332 | ||
333 | if (indio_dev->available_scan_masks) { | |
334 | mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
335 | indio_dev->masklength, | |
1e1ec286 | 336 | trialmask, false); |
217a5cf0 LPC |
337 | if (!mask) |
338 | goto err_invalid_mask; | |
339 | } | |
340 | bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength); | |
341 | ||
3862828a | 342 | bitmap_free(trialmask); |
217a5cf0 LPC |
343 | |
344 | return 0; | |
345 | ||
346 | err_invalid_mask: | |
3862828a | 347 | bitmap_free(trialmask); |
217a5cf0 LPC |
348 | return -EINVAL; |
349 | } | |
350 | ||
14555b14 | 351 | static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit) |
8d213f24 | 352 | { |
14555b14 | 353 | clear_bit(bit, buffer->scan_mask); |
8d213f24 JC |
354 | return 0; |
355 | } | |
356 | ||
c2bf8d5f JC |
357 | static int iio_scan_mask_query(struct iio_dev *indio_dev, |
358 | struct iio_buffer *buffer, int bit) | |
359 | { | |
360 | if (bit > indio_dev->masklength) | |
361 | return -EINVAL; | |
362 | ||
363 | if (!buffer->scan_mask) | |
364 | return 0; | |
365 | ||
366 | /* Ensure return value is 0 or 1. */ | |
367 | return !!test_bit(bit, buffer->scan_mask); | |
368 | }; | |
369 | ||
8d213f24 JC |
370 | static ssize_t iio_scan_el_store(struct device *dev, |
371 | struct device_attribute *attr, | |
372 | const char *buf, | |
373 | size_t len) | |
374 | { | |
a714af27 | 375 | int ret; |
8d213f24 | 376 | bool state; |
e53f5ac5 | 377 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 378 | struct iio_buffer *buffer = indio_dev->buffer; |
8d213f24 JC |
379 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
380 | ||
a714af27 JC |
381 | ret = strtobool(buf, &state); |
382 | if (ret < 0) | |
383 | return ret; | |
8d213f24 | 384 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 385 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
386 | ret = -EBUSY; |
387 | goto error_ret; | |
388 | } | |
f79a9098 | 389 | ret = iio_scan_mask_query(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
390 | if (ret < 0) |
391 | goto error_ret; | |
392 | if (!state && ret) { | |
14555b14 | 393 | ret = iio_scan_mask_clear(buffer, this_attr->address); |
8d213f24 JC |
394 | if (ret) |
395 | goto error_ret; | |
396 | } else if (state && !ret) { | |
f79a9098 | 397 | ret = iio_scan_mask_set(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
398 | if (ret) |
399 | goto error_ret; | |
400 | } | |
401 | ||
402 | error_ret: | |
403 | mutex_unlock(&indio_dev->mlock); | |
404 | ||
5a2a6e11 | 405 | return ret < 0 ? ret : len; |
8d213f24 JC |
406 | |
407 | } | |
408 | ||
409 | static ssize_t iio_scan_el_ts_show(struct device *dev, | |
410 | struct device_attribute *attr, | |
411 | char *buf) | |
412 | { | |
e53f5ac5 | 413 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
f8c6f4e9 | 414 | return sprintf(buf, "%d\n", indio_dev->buffer->scan_timestamp); |
8d213f24 JC |
415 | } |
416 | ||
417 | static ssize_t iio_scan_el_ts_store(struct device *dev, | |
418 | struct device_attribute *attr, | |
419 | const char *buf, | |
420 | size_t len) | |
421 | { | |
a714af27 | 422 | int ret; |
e53f5ac5 | 423 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 424 | bool state; |
1aa04278 | 425 | |
a714af27 JC |
426 | ret = strtobool(buf, &state); |
427 | if (ret < 0) | |
428 | return ret; | |
429 | ||
8d213f24 | 430 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 431 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
432 | ret = -EBUSY; |
433 | goto error_ret; | |
434 | } | |
14555b14 | 435 | indio_dev->buffer->scan_timestamp = state; |
8d213f24 JC |
436 | error_ret: |
437 | mutex_unlock(&indio_dev->mlock); | |
438 | ||
439 | return ret ? ret : len; | |
440 | } | |
441 | ||
14555b14 JC |
442 | static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev, |
443 | const struct iio_chan_spec *chan) | |
1d892719 | 444 | { |
26d25ae3 | 445 | int ret, attrcount = 0; |
14555b14 | 446 | struct iio_buffer *buffer = indio_dev->buffer; |
1d892719 | 447 | |
26d25ae3 | 448 | ret = __iio_add_chan_devattr("index", |
1d892719 JC |
449 | chan, |
450 | &iio_show_scan_index, | |
451 | NULL, | |
452 | 0, | |
3704432f | 453 | IIO_SEPARATE, |
1aa04278 | 454 | &indio_dev->dev, |
14555b14 | 455 | &buffer->scan_el_dev_attr_list); |
1d892719 | 456 | if (ret) |
92825ff9 | 457 | return ret; |
26d25ae3 JC |
458 | attrcount++; |
459 | ret = __iio_add_chan_devattr("type", | |
1d892719 JC |
460 | chan, |
461 | &iio_show_fixed_type, | |
462 | NULL, | |
463 | 0, | |
464 | 0, | |
1aa04278 | 465 | &indio_dev->dev, |
14555b14 | 466 | &buffer->scan_el_dev_attr_list); |
1d892719 | 467 | if (ret) |
92825ff9 | 468 | return ret; |
26d25ae3 | 469 | attrcount++; |
a88b3ebc | 470 | if (chan->type != IIO_TIMESTAMP) |
26d25ae3 | 471 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
472 | chan, |
473 | &iio_scan_el_show, | |
474 | &iio_scan_el_store, | |
475 | chan->scan_index, | |
476 | 0, | |
1aa04278 | 477 | &indio_dev->dev, |
14555b14 | 478 | &buffer->scan_el_dev_attr_list); |
a88b3ebc | 479 | else |
26d25ae3 | 480 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
481 | chan, |
482 | &iio_scan_el_ts_show, | |
483 | &iio_scan_el_ts_store, | |
484 | chan->scan_index, | |
485 | 0, | |
1aa04278 | 486 | &indio_dev->dev, |
14555b14 | 487 | &buffer->scan_el_dev_attr_list); |
9572588c | 488 | if (ret) |
92825ff9 | 489 | return ret; |
26d25ae3 JC |
490 | attrcount++; |
491 | ret = attrcount; | |
1d892719 JC |
492 | return ret; |
493 | } | |
494 | ||
08e7e0ad LPC |
495 | static ssize_t iio_buffer_read_length(struct device *dev, |
496 | struct device_attribute *attr, | |
497 | char *buf) | |
7026ea4b | 498 | { |
e53f5ac5 | 499 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 500 | struct iio_buffer *buffer = indio_dev->buffer; |
7026ea4b | 501 | |
37495660 | 502 | return sprintf(buf, "%d\n", buffer->length); |
7026ea4b | 503 | } |
7026ea4b | 504 | |
08e7e0ad LPC |
505 | static ssize_t iio_buffer_write_length(struct device *dev, |
506 | struct device_attribute *attr, | |
507 | const char *buf, size_t len) | |
7026ea4b | 508 | { |
e53f5ac5 | 509 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 510 | struct iio_buffer *buffer = indio_dev->buffer; |
948ad205 LPC |
511 | unsigned int val; |
512 | int ret; | |
8d213f24 | 513 | |
948ad205 | 514 | ret = kstrtouint(buf, 10, &val); |
7026ea4b JC |
515 | if (ret) |
516 | return ret; | |
517 | ||
37495660 LPC |
518 | if (val == buffer->length) |
519 | return len; | |
7026ea4b | 520 | |
e38c79e0 | 521 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 522 | if (iio_buffer_is_active(indio_dev->buffer)) { |
e38c79e0 LPC |
523 | ret = -EBUSY; |
524 | } else { | |
8d92db28 | 525 | buffer->access->set_length(buffer, val); |
e38c79e0 | 526 | ret = 0; |
7026ea4b | 527 | } |
37d34556 JC |
528 | if (ret) |
529 | goto out; | |
530 | if (buffer->length && buffer->length < buffer->watermark) | |
531 | buffer->watermark = buffer->length; | |
532 | out: | |
e38c79e0 | 533 | mutex_unlock(&indio_dev->mlock); |
7026ea4b | 534 | |
e38c79e0 | 535 | return ret ? ret : len; |
7026ea4b | 536 | } |
7026ea4b | 537 | |
08e7e0ad LPC |
538 | static ssize_t iio_buffer_show_enable(struct device *dev, |
539 | struct device_attribute *attr, | |
540 | char *buf) | |
7026ea4b | 541 | { |
e53f5ac5 | 542 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
705ee2c9 | 543 | return sprintf(buf, "%d\n", iio_buffer_is_active(indio_dev->buffer)); |
7026ea4b | 544 | } |
7026ea4b | 545 | |
182b4905 LPC |
546 | static unsigned int iio_storage_bytes_for_si(struct iio_dev *indio_dev, |
547 | unsigned int scan_index) | |
548 | { | |
549 | const struct iio_chan_spec *ch; | |
550 | unsigned int bytes; | |
551 | ||
552 | ch = iio_find_channel_from_si(indio_dev, scan_index); | |
553 | bytes = ch->scan_type.storagebits / 8; | |
554 | if (ch->scan_type.repeat > 1) | |
555 | bytes *= ch->scan_type.repeat; | |
556 | return bytes; | |
557 | } | |
558 | ||
559 | static unsigned int iio_storage_bytes_for_timestamp(struct iio_dev *indio_dev) | |
560 | { | |
561 | return iio_storage_bytes_for_si(indio_dev, | |
562 | indio_dev->scan_index_timestamp); | |
563 | } | |
564 | ||
183f4173 PM |
565 | static int iio_compute_scan_bytes(struct iio_dev *indio_dev, |
566 | const unsigned long *mask, bool timestamp) | |
959d2952 | 567 | { |
959d2952 JC |
568 | unsigned bytes = 0; |
569 | int length, i; | |
959d2952 JC |
570 | |
571 | /* How much space will the demuxed element take? */ | |
6b3b58ed | 572 | for_each_set_bit(i, mask, |
959d2952 | 573 | indio_dev->masklength) { |
182b4905 | 574 | length = iio_storage_bytes_for_si(indio_dev, i); |
959d2952 JC |
575 | bytes = ALIGN(bytes, length); |
576 | bytes += length; | |
577 | } | |
182b4905 | 578 | |
6b3b58ed | 579 | if (timestamp) { |
182b4905 | 580 | length = iio_storage_bytes_for_timestamp(indio_dev); |
959d2952 JC |
581 | bytes = ALIGN(bytes, length); |
582 | bytes += length; | |
583 | } | |
6b3b58ed JC |
584 | return bytes; |
585 | } | |
586 | ||
9e69c935 LPC |
587 | static void iio_buffer_activate(struct iio_dev *indio_dev, |
588 | struct iio_buffer *buffer) | |
589 | { | |
590 | iio_buffer_get(buffer); | |
591 | list_add(&buffer->buffer_list, &indio_dev->buffer_list); | |
592 | } | |
593 | ||
594 | static void iio_buffer_deactivate(struct iio_buffer *buffer) | |
595 | { | |
596 | list_del_init(&buffer->buffer_list); | |
37d34556 | 597 | wake_up_interruptible(&buffer->pollq); |
9e69c935 LPC |
598 | iio_buffer_put(buffer); |
599 | } | |
600 | ||
1250186a LPC |
601 | static void iio_buffer_deactivate_all(struct iio_dev *indio_dev) |
602 | { | |
603 | struct iio_buffer *buffer, *_buffer; | |
604 | ||
605 | list_for_each_entry_safe(buffer, _buffer, | |
606 | &indio_dev->buffer_list, buffer_list) | |
607 | iio_buffer_deactivate(buffer); | |
608 | } | |
609 | ||
e18a2ad4 LPC |
610 | static int iio_buffer_enable(struct iio_buffer *buffer, |
611 | struct iio_dev *indio_dev) | |
612 | { | |
613 | if (!buffer->access->enable) | |
614 | return 0; | |
615 | return buffer->access->enable(buffer, indio_dev); | |
616 | } | |
617 | ||
618 | static int iio_buffer_disable(struct iio_buffer *buffer, | |
619 | struct iio_dev *indio_dev) | |
620 | { | |
621 | if (!buffer->access->disable) | |
622 | return 0; | |
623 | return buffer->access->disable(buffer, indio_dev); | |
624 | } | |
625 | ||
8e050996 LPC |
626 | static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev, |
627 | struct iio_buffer *buffer) | |
628 | { | |
629 | unsigned int bytes; | |
630 | ||
631 | if (!buffer->access->set_bytes_per_datum) | |
632 | return; | |
633 | ||
634 | bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask, | |
635 | buffer->scan_timestamp); | |
636 | ||
637 | buffer->access->set_bytes_per_datum(buffer, bytes); | |
638 | } | |
639 | ||
fcc1b2f5 LPC |
640 | static int iio_buffer_request_update(struct iio_dev *indio_dev, |
641 | struct iio_buffer *buffer) | |
642 | { | |
643 | int ret; | |
644 | ||
645 | iio_buffer_update_bytes_per_datum(indio_dev, buffer); | |
646 | if (buffer->access->request_update) { | |
647 | ret = buffer->access->request_update(buffer); | |
648 | if (ret) { | |
649 | dev_dbg(&indio_dev->dev, | |
650 | "Buffer not started: buffer parameter update failed (%d)\n", | |
651 | ret); | |
652 | return ret; | |
653 | } | |
654 | } | |
655 | ||
656 | return 0; | |
657 | } | |
658 | ||
248be5aa LPC |
659 | static void iio_free_scan_mask(struct iio_dev *indio_dev, |
660 | const unsigned long *mask) | |
661 | { | |
662 | /* If the mask is dynamically allocated free it, otherwise do nothing */ | |
663 | if (!indio_dev->available_scan_masks) | |
3862828a | 664 | bitmap_free(mask); |
248be5aa LPC |
665 | } |
666 | ||
6e509c4d LPC |
667 | struct iio_device_config { |
668 | unsigned int mode; | |
f0566c0c | 669 | unsigned int watermark; |
6e509c4d LPC |
670 | const unsigned long *scan_mask; |
671 | unsigned int scan_bytes; | |
672 | bool scan_timestamp; | |
673 | }; | |
674 | ||
675 | static int iio_verify_update(struct iio_dev *indio_dev, | |
676 | struct iio_buffer *insert_buffer, struct iio_buffer *remove_buffer, | |
677 | struct iio_device_config *config) | |
678 | { | |
679 | unsigned long *compound_mask; | |
680 | const unsigned long *scan_mask; | |
1e1ec286 | 681 | bool strict_scanmask = false; |
6e509c4d LPC |
682 | struct iio_buffer *buffer; |
683 | bool scan_timestamp; | |
225d59ad | 684 | unsigned int modes; |
6e509c4d LPC |
685 | |
686 | memset(config, 0, sizeof(*config)); | |
1bef2c1d | 687 | config->watermark = ~0; |
6e509c4d LPC |
688 | |
689 | /* | |
690 | * If there is just one buffer and we are removing it there is nothing | |
691 | * to verify. | |
692 | */ | |
693 | if (remove_buffer && !insert_buffer && | |
694 | list_is_singular(&indio_dev->buffer_list)) | |
695 | return 0; | |
696 | ||
225d59ad LPC |
697 | modes = indio_dev->modes; |
698 | ||
699 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
700 | if (buffer == remove_buffer) | |
701 | continue; | |
702 | modes &= buffer->access->modes; | |
f0566c0c | 703 | config->watermark = min(config->watermark, buffer->watermark); |
225d59ad LPC |
704 | } |
705 | ||
f0566c0c | 706 | if (insert_buffer) { |
225d59ad | 707 | modes &= insert_buffer->access->modes; |
f0566c0c LPC |
708 | config->watermark = min(config->watermark, |
709 | insert_buffer->watermark); | |
710 | } | |
225d59ad | 711 | |
6e509c4d | 712 | /* Definitely possible for devices to support both of these. */ |
225d59ad | 713 | if ((modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) { |
6e509c4d | 714 | config->mode = INDIO_BUFFER_TRIGGERED; |
225d59ad | 715 | } else if (modes & INDIO_BUFFER_HARDWARE) { |
1e1ec286 LPC |
716 | /* |
717 | * Keep things simple for now and only allow a single buffer to | |
718 | * be connected in hardware mode. | |
719 | */ | |
720 | if (insert_buffer && !list_empty(&indio_dev->buffer_list)) | |
721 | return -EINVAL; | |
6e509c4d | 722 | config->mode = INDIO_BUFFER_HARDWARE; |
1e1ec286 | 723 | strict_scanmask = true; |
225d59ad | 724 | } else if (modes & INDIO_BUFFER_SOFTWARE) { |
6e509c4d LPC |
725 | config->mode = INDIO_BUFFER_SOFTWARE; |
726 | } else { | |
727 | /* Can only occur on first buffer */ | |
728 | if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) | |
729 | dev_dbg(&indio_dev->dev, "Buffer not started: no trigger\n"); | |
730 | return -EINVAL; | |
731 | } | |
732 | ||
733 | /* What scan mask do we actually have? */ | |
3862828a | 734 | compound_mask = bitmap_zalloc(indio_dev->masklength, GFP_KERNEL); |
6e509c4d LPC |
735 | if (compound_mask == NULL) |
736 | return -ENOMEM; | |
737 | ||
738 | scan_timestamp = false; | |
739 | ||
740 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
741 | if (buffer == remove_buffer) | |
742 | continue; | |
743 | bitmap_or(compound_mask, compound_mask, buffer->scan_mask, | |
744 | indio_dev->masklength); | |
745 | scan_timestamp |= buffer->scan_timestamp; | |
746 | } | |
747 | ||
748 | if (insert_buffer) { | |
749 | bitmap_or(compound_mask, compound_mask, | |
750 | insert_buffer->scan_mask, indio_dev->masklength); | |
751 | scan_timestamp |= insert_buffer->scan_timestamp; | |
752 | } | |
753 | ||
754 | if (indio_dev->available_scan_masks) { | |
755 | scan_mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
756 | indio_dev->masklength, | |
1e1ec286 LPC |
757 | compound_mask, |
758 | strict_scanmask); | |
3862828a | 759 | bitmap_free(compound_mask); |
6e509c4d LPC |
760 | if (scan_mask == NULL) |
761 | return -EINVAL; | |
762 | } else { | |
763 | scan_mask = compound_mask; | |
764 | } | |
765 | ||
766 | config->scan_bytes = iio_compute_scan_bytes(indio_dev, | |
767 | scan_mask, scan_timestamp); | |
768 | config->scan_mask = scan_mask; | |
769 | config->scan_timestamp = scan_timestamp; | |
770 | ||
771 | return 0; | |
772 | } | |
773 | ||
78c9981f JC |
774 | /** |
775 | * struct iio_demux_table - table describing demux memcpy ops | |
776 | * @from: index to copy from | |
777 | * @to: index to copy to | |
778 | * @length: how many bytes to copy | |
779 | * @l: list head used for management | |
780 | */ | |
781 | struct iio_demux_table { | |
782 | unsigned from; | |
783 | unsigned to; | |
784 | unsigned length; | |
785 | struct list_head l; | |
786 | }; | |
787 | ||
788 | static void iio_buffer_demux_free(struct iio_buffer *buffer) | |
789 | { | |
790 | struct iio_demux_table *p, *q; | |
791 | list_for_each_entry_safe(p, q, &buffer->demux_list, l) { | |
792 | list_del(&p->l); | |
793 | kfree(p); | |
794 | } | |
795 | } | |
796 | ||
797 | static int iio_buffer_add_demux(struct iio_buffer *buffer, | |
798 | struct iio_demux_table **p, unsigned int in_loc, unsigned int out_loc, | |
799 | unsigned int length) | |
800 | { | |
801 | ||
802 | if (*p && (*p)->from + (*p)->length == in_loc && | |
803 | (*p)->to + (*p)->length == out_loc) { | |
804 | (*p)->length += length; | |
805 | } else { | |
806 | *p = kmalloc(sizeof(**p), GFP_KERNEL); | |
807 | if (*p == NULL) | |
808 | return -ENOMEM; | |
809 | (*p)->from = in_loc; | |
810 | (*p)->to = out_loc; | |
811 | (*p)->length = length; | |
812 | list_add_tail(&(*p)->l, &buffer->demux_list); | |
813 | } | |
814 | ||
815 | return 0; | |
816 | } | |
817 | ||
818 | static int iio_buffer_update_demux(struct iio_dev *indio_dev, | |
819 | struct iio_buffer *buffer) | |
820 | { | |
821 | int ret, in_ind = -1, out_ind, length; | |
822 | unsigned in_loc = 0, out_loc = 0; | |
823 | struct iio_demux_table *p = NULL; | |
824 | ||
825 | /* Clear out any old demux */ | |
826 | iio_buffer_demux_free(buffer); | |
827 | kfree(buffer->demux_bounce); | |
828 | buffer->demux_bounce = NULL; | |
829 | ||
830 | /* First work out which scan mode we will actually have */ | |
831 | if (bitmap_equal(indio_dev->active_scan_mask, | |
832 | buffer->scan_mask, | |
833 | indio_dev->masklength)) | |
834 | return 0; | |
835 | ||
836 | /* Now we have the two masks, work from least sig and build up sizes */ | |
837 | for_each_set_bit(out_ind, | |
838 | buffer->scan_mask, | |
839 | indio_dev->masklength) { | |
840 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
841 | indio_dev->masklength, | |
842 | in_ind + 1); | |
843 | while (in_ind != out_ind) { | |
844 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
845 | indio_dev->masklength, | |
846 | in_ind + 1); | |
847 | length = iio_storage_bytes_for_si(indio_dev, in_ind); | |
848 | /* Make sure we are aligned */ | |
849 | in_loc = roundup(in_loc, length) + length; | |
850 | } | |
851 | length = iio_storage_bytes_for_si(indio_dev, in_ind); | |
852 | out_loc = roundup(out_loc, length); | |
853 | in_loc = roundup(in_loc, length); | |
854 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); | |
855 | if (ret) | |
856 | goto error_clear_mux_table; | |
857 | out_loc += length; | |
858 | in_loc += length; | |
859 | } | |
860 | /* Relies on scan_timestamp being last */ | |
861 | if (buffer->scan_timestamp) { | |
862 | length = iio_storage_bytes_for_timestamp(indio_dev); | |
863 | out_loc = roundup(out_loc, length); | |
864 | in_loc = roundup(in_loc, length); | |
865 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); | |
866 | if (ret) | |
867 | goto error_clear_mux_table; | |
868 | out_loc += length; | |
869 | in_loc += length; | |
870 | } | |
871 | buffer->demux_bounce = kzalloc(out_loc, GFP_KERNEL); | |
872 | if (buffer->demux_bounce == NULL) { | |
873 | ret = -ENOMEM; | |
874 | goto error_clear_mux_table; | |
875 | } | |
876 | return 0; | |
877 | ||
878 | error_clear_mux_table: | |
879 | iio_buffer_demux_free(buffer); | |
880 | ||
881 | return ret; | |
882 | } | |
883 | ||
884 | static int iio_update_demux(struct iio_dev *indio_dev) | |
885 | { | |
886 | struct iio_buffer *buffer; | |
887 | int ret; | |
888 | ||
889 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
890 | ret = iio_buffer_update_demux(indio_dev, buffer); | |
891 | if (ret < 0) | |
892 | goto error_clear_mux_table; | |
893 | } | |
894 | return 0; | |
895 | ||
896 | error_clear_mux_table: | |
897 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) | |
898 | iio_buffer_demux_free(buffer); | |
899 | ||
900 | return ret; | |
901 | } | |
902 | ||
623d74e3 LPC |
903 | static int iio_enable_buffers(struct iio_dev *indio_dev, |
904 | struct iio_device_config *config) | |
6b3b58ed | 905 | { |
e18a2ad4 | 906 | struct iio_buffer *buffer; |
84b36ce5 | 907 | int ret; |
fcc1b2f5 | 908 | |
623d74e3 LPC |
909 | indio_dev->active_scan_mask = config->scan_mask; |
910 | indio_dev->scan_timestamp = config->scan_timestamp; | |
911 | indio_dev->scan_bytes = config->scan_bytes; | |
aff1eb4e | 912 | |
5ada4ea9 JC |
913 | iio_update_demux(indio_dev); |
914 | ||
84b36ce5 JC |
915 | /* Wind up again */ |
916 | if (indio_dev->setup_ops->preenable) { | |
917 | ret = indio_dev->setup_ops->preenable(indio_dev); | |
918 | if (ret) { | |
63223c5f | 919 | dev_dbg(&indio_dev->dev, |
bec1889d | 920 | "Buffer not started: buffer preenable failed (%d)\n", ret); |
623d74e3 | 921 | goto err_undo_config; |
84b36ce5 JC |
922 | } |
923 | } | |
6e509c4d | 924 | |
84b36ce5 JC |
925 | if (indio_dev->info->update_scan_mode) { |
926 | ret = indio_dev->info | |
5ada4ea9 JC |
927 | ->update_scan_mode(indio_dev, |
928 | indio_dev->active_scan_mask); | |
84b36ce5 | 929 | if (ret < 0) { |
63223c5f LPC |
930 | dev_dbg(&indio_dev->dev, |
931 | "Buffer not started: update scan mode failed (%d)\n", | |
932 | ret); | |
623d74e3 | 933 | goto err_run_postdisable; |
84b36ce5 JC |
934 | } |
935 | } | |
6e509c4d | 936 | |
f0566c0c LPC |
937 | if (indio_dev->info->hwfifo_set_watermark) |
938 | indio_dev->info->hwfifo_set_watermark(indio_dev, | |
939 | config->watermark); | |
940 | ||
e18a2ad4 LPC |
941 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { |
942 | ret = iio_buffer_enable(buffer, indio_dev); | |
943 | if (ret) | |
944 | goto err_disable_buffers; | |
945 | } | |
946 | ||
623d74e3 | 947 | indio_dev->currentmode = config->mode; |
84b36ce5 JC |
948 | |
949 | if (indio_dev->setup_ops->postenable) { | |
950 | ret = indio_dev->setup_ops->postenable(indio_dev); | |
951 | if (ret) { | |
63223c5f | 952 | dev_dbg(&indio_dev->dev, |
bec1889d | 953 | "Buffer not started: postenable failed (%d)\n", ret); |
e18a2ad4 | 954 | goto err_disable_buffers; |
84b36ce5 JC |
955 | } |
956 | } | |
957 | ||
6e509c4d | 958 | return 0; |
84b36ce5 | 959 | |
e18a2ad4 LPC |
960 | err_disable_buffers: |
961 | list_for_each_entry_continue_reverse(buffer, &indio_dev->buffer_list, | |
962 | buffer_list) | |
963 | iio_buffer_disable(buffer, indio_dev); | |
623d74e3 | 964 | err_run_postdisable: |
84b36ce5 | 965 | indio_dev->currentmode = INDIO_DIRECT_MODE; |
84b36ce5 JC |
966 | if (indio_dev->setup_ops->postdisable) |
967 | indio_dev->setup_ops->postdisable(indio_dev); | |
623d74e3 LPC |
968 | err_undo_config: |
969 | indio_dev->active_scan_mask = NULL; | |
970 | ||
84b36ce5 | 971 | return ret; |
623d74e3 LPC |
972 | } |
973 | ||
974 | static int iio_disable_buffers(struct iio_dev *indio_dev) | |
975 | { | |
e18a2ad4 | 976 | struct iio_buffer *buffer; |
1250186a LPC |
977 | int ret = 0; |
978 | int ret2; | |
623d74e3 LPC |
979 | |
980 | /* Wind down existing buffers - iff there are any */ | |
981 | if (list_empty(&indio_dev->buffer_list)) | |
982 | return 0; | |
983 | ||
1250186a LPC |
984 | /* |
985 | * If things go wrong at some step in disable we still need to continue | |
986 | * to perform the other steps, otherwise we leave the device in a | |
987 | * inconsistent state. We return the error code for the first error we | |
988 | * encountered. | |
989 | */ | |
990 | ||
623d74e3 | 991 | if (indio_dev->setup_ops->predisable) { |
1250186a LPC |
992 | ret2 = indio_dev->setup_ops->predisable(indio_dev); |
993 | if (ret2 && !ret) | |
994 | ret = ret2; | |
623d74e3 | 995 | } |
e18a2ad4 LPC |
996 | |
997 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
998 | ret2 = iio_buffer_disable(buffer, indio_dev); | |
999 | if (ret2 && !ret) | |
1000 | ret = ret2; | |
1001 | } | |
623d74e3 LPC |
1002 | |
1003 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
1004 | ||
1005 | if (indio_dev->setup_ops->postdisable) { | |
1250186a LPC |
1006 | ret2 = indio_dev->setup_ops->postdisable(indio_dev); |
1007 | if (ret2 && !ret) | |
1008 | ret = ret2; | |
623d74e3 LPC |
1009 | } |
1010 | ||
1250186a LPC |
1011 | iio_free_scan_mask(indio_dev, indio_dev->active_scan_mask); |
1012 | indio_dev->active_scan_mask = NULL; | |
1013 | ||
1014 | return ret; | |
623d74e3 LPC |
1015 | } |
1016 | ||
1017 | static int __iio_update_buffers(struct iio_dev *indio_dev, | |
1018 | struct iio_buffer *insert_buffer, | |
1019 | struct iio_buffer *remove_buffer) | |
1020 | { | |
623d74e3 | 1021 | struct iio_device_config new_config; |
1250186a | 1022 | int ret; |
623d74e3 LPC |
1023 | |
1024 | ret = iio_verify_update(indio_dev, insert_buffer, remove_buffer, | |
1025 | &new_config); | |
1026 | if (ret) | |
1027 | return ret; | |
1028 | ||
1029 | if (insert_buffer) { | |
1030 | ret = iio_buffer_request_update(indio_dev, insert_buffer); | |
1031 | if (ret) | |
1032 | goto err_free_config; | |
1033 | } | |
1034 | ||
623d74e3 | 1035 | ret = iio_disable_buffers(indio_dev); |
1250186a LPC |
1036 | if (ret) |
1037 | goto err_deactivate_all; | |
623d74e3 LPC |
1038 | |
1039 | if (remove_buffer) | |
1040 | iio_buffer_deactivate(remove_buffer); | |
1041 | if (insert_buffer) | |
1042 | iio_buffer_activate(indio_dev, insert_buffer); | |
1043 | ||
1044 | /* If no buffers in list, we are done */ | |
1250186a | 1045 | if (list_empty(&indio_dev->buffer_list)) |
623d74e3 | 1046 | return 0; |
623d74e3 LPC |
1047 | |
1048 | ret = iio_enable_buffers(indio_dev, &new_config); | |
1250186a LPC |
1049 | if (ret) |
1050 | goto err_deactivate_all; | |
623d74e3 | 1051 | |
623d74e3 | 1052 | return 0; |
6e509c4d | 1053 | |
1250186a LPC |
1054 | err_deactivate_all: |
1055 | /* | |
1056 | * We've already verified that the config is valid earlier. If things go | |
1057 | * wrong in either enable or disable the most likely reason is an IO | |
1058 | * error from the device. In this case there is no good recovery | |
1059 | * strategy. Just make sure to disable everything and leave the device | |
1060 | * in a sane state. With a bit of luck the device might come back to | |
1061 | * life again later and userspace can try again. | |
1062 | */ | |
1063 | iio_buffer_deactivate_all(indio_dev); | |
1064 | ||
6e509c4d LPC |
1065 | err_free_config: |
1066 | iio_free_scan_mask(indio_dev, new_config.scan_mask); | |
1067 | return ret; | |
84b36ce5 | 1068 | } |
a9519456 LPC |
1069 | |
1070 | int iio_update_buffers(struct iio_dev *indio_dev, | |
1071 | struct iio_buffer *insert_buffer, | |
1072 | struct iio_buffer *remove_buffer) | |
1073 | { | |
1074 | int ret; | |
1075 | ||
3909fab5 LPC |
1076 | if (insert_buffer == remove_buffer) |
1077 | return 0; | |
1078 | ||
a9519456 LPC |
1079 | mutex_lock(&indio_dev->info_exist_lock); |
1080 | mutex_lock(&indio_dev->mlock); | |
1081 | ||
3909fab5 LPC |
1082 | if (insert_buffer && iio_buffer_is_active(insert_buffer)) |
1083 | insert_buffer = NULL; | |
1084 | ||
1085 | if (remove_buffer && !iio_buffer_is_active(remove_buffer)) | |
1086 | remove_buffer = NULL; | |
1087 | ||
1088 | if (!insert_buffer && !remove_buffer) { | |
1089 | ret = 0; | |
1090 | goto out_unlock; | |
1091 | } | |
1092 | ||
a9519456 LPC |
1093 | if (indio_dev->info == NULL) { |
1094 | ret = -ENODEV; | |
1095 | goto out_unlock; | |
1096 | } | |
1097 | ||
1098 | ret = __iio_update_buffers(indio_dev, insert_buffer, remove_buffer); | |
1099 | ||
1100 | out_unlock: | |
1101 | mutex_unlock(&indio_dev->mlock); | |
1102 | mutex_unlock(&indio_dev->info_exist_lock); | |
1103 | ||
1104 | return ret; | |
1105 | } | |
84b36ce5 JC |
1106 | EXPORT_SYMBOL_GPL(iio_update_buffers); |
1107 | ||
623d74e3 LPC |
1108 | void iio_disable_all_buffers(struct iio_dev *indio_dev) |
1109 | { | |
623d74e3 | 1110 | iio_disable_buffers(indio_dev); |
1250186a | 1111 | iio_buffer_deactivate_all(indio_dev); |
623d74e3 LPC |
1112 | } |
1113 | ||
08e7e0ad LPC |
1114 | static ssize_t iio_buffer_store_enable(struct device *dev, |
1115 | struct device_attribute *attr, | |
1116 | const char *buf, | |
1117 | size_t len) | |
84b36ce5 JC |
1118 | { |
1119 | int ret; | |
1120 | bool requested_state; | |
1121 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
84b36ce5 JC |
1122 | bool inlist; |
1123 | ||
1124 | ret = strtobool(buf, &requested_state); | |
1125 | if (ret < 0) | |
1126 | return ret; | |
1127 | ||
1128 | mutex_lock(&indio_dev->mlock); | |
1129 | ||
1130 | /* Find out if it is in the list */ | |
705ee2c9 | 1131 | inlist = iio_buffer_is_active(indio_dev->buffer); |
84b36ce5 JC |
1132 | /* Already in desired state */ |
1133 | if (inlist == requested_state) | |
1134 | goto done; | |
1135 | ||
1136 | if (requested_state) | |
a9519456 | 1137 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
1138 | indio_dev->buffer, NULL); |
1139 | else | |
a9519456 | 1140 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
1141 | NULL, indio_dev->buffer); |
1142 | ||
84b36ce5 JC |
1143 | done: |
1144 | mutex_unlock(&indio_dev->mlock); | |
1145 | return (ret < 0) ? ret : len; | |
1146 | } | |
84b36ce5 | 1147 | |
d967cb6b LPC |
1148 | static const char * const iio_scan_elements_group_name = "scan_elements"; |
1149 | ||
37d34556 JC |
1150 | static ssize_t iio_buffer_show_watermark(struct device *dev, |
1151 | struct device_attribute *attr, | |
1152 | char *buf) | |
1153 | { | |
1154 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1155 | struct iio_buffer *buffer = indio_dev->buffer; | |
1156 | ||
1157 | return sprintf(buf, "%u\n", buffer->watermark); | |
1158 | } | |
1159 | ||
1160 | static ssize_t iio_buffer_store_watermark(struct device *dev, | |
1161 | struct device_attribute *attr, | |
1162 | const char *buf, | |
1163 | size_t len) | |
1164 | { | |
1165 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1166 | struct iio_buffer *buffer = indio_dev->buffer; | |
1167 | unsigned int val; | |
1168 | int ret; | |
1169 | ||
1170 | ret = kstrtouint(buf, 10, &val); | |
1171 | if (ret) | |
1172 | return ret; | |
1173 | if (!val) | |
1174 | return -EINVAL; | |
1175 | ||
1176 | mutex_lock(&indio_dev->mlock); | |
1177 | ||
1178 | if (val > buffer->length) { | |
1179 | ret = -EINVAL; | |
1180 | goto out; | |
1181 | } | |
1182 | ||
1183 | if (iio_buffer_is_active(indio_dev->buffer)) { | |
1184 | ret = -EBUSY; | |
1185 | goto out; | |
1186 | } | |
1187 | ||
1188 | buffer->watermark = val; | |
1189 | out: | |
1190 | mutex_unlock(&indio_dev->mlock); | |
1191 | ||
1192 | return ret ? ret : len; | |
1193 | } | |
1194 | ||
350f6c75 MF |
1195 | static ssize_t iio_dma_show_data_available(struct device *dev, |
1196 | struct device_attribute *attr, | |
1197 | char *buf) | |
1198 | { | |
1199 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1200 | size_t bytes; | |
1201 | ||
1202 | bytes = iio_buffer_data_available(indio_dev->buffer); | |
1203 | ||
1204 | return sprintf(buf, "%zu\n", bytes); | |
1205 | } | |
1206 | ||
08e7e0ad LPC |
1207 | static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length, |
1208 | iio_buffer_write_length); | |
8d92db28 LPC |
1209 | static struct device_attribute dev_attr_length_ro = __ATTR(length, |
1210 | S_IRUGO, iio_buffer_read_length, NULL); | |
08e7e0ad LPC |
1211 | static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, |
1212 | iio_buffer_show_enable, iio_buffer_store_enable); | |
37d34556 JC |
1213 | static DEVICE_ATTR(watermark, S_IRUGO | S_IWUSR, |
1214 | iio_buffer_show_watermark, iio_buffer_store_watermark); | |
b440655b LPC |
1215 | static struct device_attribute dev_attr_watermark_ro = __ATTR(watermark, |
1216 | S_IRUGO, iio_buffer_show_watermark, NULL); | |
350f6c75 MF |
1217 | static DEVICE_ATTR(data_available, S_IRUGO, |
1218 | iio_dma_show_data_available, NULL); | |
08e7e0ad | 1219 | |
6da9b382 OP |
1220 | static struct attribute *iio_buffer_attrs[] = { |
1221 | &dev_attr_length.attr, | |
1222 | &dev_attr_enable.attr, | |
37d34556 | 1223 | &dev_attr_watermark.attr, |
350f6c75 | 1224 | &dev_attr_data_available.attr, |
6da9b382 OP |
1225 | }; |
1226 | ||
d967cb6b LPC |
1227 | int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev) |
1228 | { | |
1229 | struct iio_dev_attr *p; | |
1230 | struct attribute **attr; | |
1231 | struct iio_buffer *buffer = indio_dev->buffer; | |
1232 | int ret, i, attrn, attrcount, attrcount_orig = 0; | |
1233 | const struct iio_chan_spec *channels; | |
1234 | ||
629bc023 LPC |
1235 | channels = indio_dev->channels; |
1236 | if (channels) { | |
1237 | int ml = indio_dev->masklength; | |
1238 | ||
1239 | for (i = 0; i < indio_dev->num_channels; i++) | |
1240 | ml = max(ml, channels[i].scan_index + 1); | |
1241 | indio_dev->masklength = ml; | |
1242 | } | |
1243 | ||
d967cb6b LPC |
1244 | if (!buffer) |
1245 | return 0; | |
1246 | ||
08e7e0ad LPC |
1247 | attrcount = 0; |
1248 | if (buffer->attrs) { | |
1249 | while (buffer->attrs[attrcount] != NULL) | |
1250 | attrcount++; | |
1251 | } | |
1252 | ||
6da9b382 OP |
1253 | attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, |
1254 | sizeof(struct attribute *), GFP_KERNEL); | |
1255 | if (!attr) | |
08e7e0ad LPC |
1256 | return -ENOMEM; |
1257 | ||
6da9b382 OP |
1258 | memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); |
1259 | if (!buffer->access->set_length) | |
1260 | attr[0] = &dev_attr_length_ro.attr; | |
1261 | ||
b440655b LPC |
1262 | if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) |
1263 | attr[2] = &dev_attr_watermark_ro.attr; | |
1264 | ||
08e7e0ad | 1265 | if (buffer->attrs) |
6da9b382 OP |
1266 | memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, |
1267 | sizeof(struct attribute *) * attrcount); | |
1268 | ||
1269 | attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; | |
1270 | ||
1271 | buffer->buffer_group.name = "buffer"; | |
1272 | buffer->buffer_group.attrs = attr; | |
08e7e0ad LPC |
1273 | |
1274 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->buffer_group; | |
1275 | ||
d967cb6b LPC |
1276 | if (buffer->scan_el_attrs != NULL) { |
1277 | attr = buffer->scan_el_attrs->attrs; | |
1278 | while (*attr++ != NULL) | |
1279 | attrcount_orig++; | |
1280 | } | |
1281 | attrcount = attrcount_orig; | |
1282 | INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); | |
1283 | channels = indio_dev->channels; | |
1284 | if (channels) { | |
1285 | /* new magic */ | |
1286 | for (i = 0; i < indio_dev->num_channels; i++) { | |
1287 | if (channels[i].scan_index < 0) | |
1288 | continue; | |
1289 | ||
d967cb6b LPC |
1290 | ret = iio_buffer_add_channel_sysfs(indio_dev, |
1291 | &channels[i]); | |
1292 | if (ret < 0) | |
1293 | goto error_cleanup_dynamic; | |
1294 | attrcount += ret; | |
1295 | if (channels[i].type == IIO_TIMESTAMP) | |
1296 | indio_dev->scan_index_timestamp = | |
1297 | channels[i].scan_index; | |
1298 | } | |
1299 | if (indio_dev->masklength && buffer->scan_mask == NULL) { | |
3862828a AS |
1300 | buffer->scan_mask = bitmap_zalloc(indio_dev->masklength, |
1301 | GFP_KERNEL); | |
d967cb6b LPC |
1302 | if (buffer->scan_mask == NULL) { |
1303 | ret = -ENOMEM; | |
1304 | goto error_cleanup_dynamic; | |
1305 | } | |
1306 | } | |
1307 | } | |
1308 | ||
1309 | buffer->scan_el_group.name = iio_scan_elements_group_name; | |
1310 | ||
1311 | buffer->scan_el_group.attrs = kcalloc(attrcount + 1, | |
1312 | sizeof(buffer->scan_el_group.attrs[0]), | |
1313 | GFP_KERNEL); | |
1314 | if (buffer->scan_el_group.attrs == NULL) { | |
1315 | ret = -ENOMEM; | |
1316 | goto error_free_scan_mask; | |
1317 | } | |
1318 | if (buffer->scan_el_attrs) | |
1319 | memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs, | |
1320 | sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig); | |
1321 | attrn = attrcount_orig; | |
1322 | ||
1323 | list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l) | |
1324 | buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr; | |
1325 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group; | |
1326 | ||
1327 | return 0; | |
1328 | ||
1329 | error_free_scan_mask: | |
3862828a | 1330 | bitmap_free(buffer->scan_mask); |
d967cb6b LPC |
1331 | error_cleanup_dynamic: |
1332 | iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); | |
08e7e0ad | 1333 | kfree(indio_dev->buffer->buffer_group.attrs); |
d967cb6b LPC |
1334 | |
1335 | return ret; | |
1336 | } | |
1337 | ||
1338 | void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev) | |
1339 | { | |
1340 | if (!indio_dev->buffer) | |
1341 | return; | |
1342 | ||
3862828a | 1343 | bitmap_free(indio_dev->buffer->scan_mask); |
08e7e0ad | 1344 | kfree(indio_dev->buffer->buffer_group.attrs); |
d967cb6b LPC |
1345 | kfree(indio_dev->buffer->scan_el_group.attrs); |
1346 | iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list); | |
1347 | } | |
1348 | ||
81636632 LPC |
1349 | /** |
1350 | * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected | |
1351 | * @indio_dev: the iio device | |
1352 | * @mask: scan mask to be checked | |
1353 | * | |
1354 | * Return true if exactly one bit is set in the scan mask, false otherwise. It | |
1355 | * can be used for devices where only one channel can be active for sampling at | |
1356 | * a time. | |
1357 | */ | |
1358 | bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, | |
1359 | const unsigned long *mask) | |
1360 | { | |
1361 | return bitmap_weight(mask, indio_dev->masklength) == 1; | |
1362 | } | |
1363 | EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot); | |
1364 | ||
5d65d920 LPC |
1365 | static const void *iio_demux(struct iio_buffer *buffer, |
1366 | const void *datain) | |
5ada4ea9 JC |
1367 | { |
1368 | struct iio_demux_table *t; | |
1369 | ||
1370 | if (list_empty(&buffer->demux_list)) | |
1371 | return datain; | |
1372 | list_for_each_entry(t, &buffer->demux_list, l) | |
1373 | memcpy(buffer->demux_bounce + t->to, | |
1374 | datain + t->from, t->length); | |
1375 | ||
1376 | return buffer->demux_bounce; | |
1377 | } | |
1378 | ||
5d65d920 | 1379 | static int iio_push_to_buffer(struct iio_buffer *buffer, const void *data) |
5ada4ea9 | 1380 | { |
5d65d920 | 1381 | const void *dataout = iio_demux(buffer, data); |
37d34556 JC |
1382 | int ret; |
1383 | ||
1384 | ret = buffer->access->store_to(buffer, dataout); | |
1385 | if (ret) | |
1386 | return ret; | |
5ada4ea9 | 1387 | |
37d34556 JC |
1388 | /* |
1389 | * We can't just test for watermark to decide if we wake the poll queue | |
1390 | * because read may request less samples than the watermark. | |
1391 | */ | |
a9a08845 | 1392 | wake_up_interruptible_poll(&buffer->pollq, EPOLLIN | EPOLLRDNORM); |
37d34556 | 1393 | return 0; |
5ada4ea9 | 1394 | } |
5ada4ea9 | 1395 | |
315a19ec JC |
1396 | /** |
1397 | * iio_push_to_buffers() - push to a registered buffer. | |
1398 | * @indio_dev: iio_dev structure for device. | |
1399 | * @data: Full scan. | |
1400 | */ | |
5d65d920 | 1401 | int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data) |
84b36ce5 JC |
1402 | { |
1403 | int ret; | |
1404 | struct iio_buffer *buf; | |
1405 | ||
1406 | list_for_each_entry(buf, &indio_dev->buffer_list, buffer_list) { | |
1407 | ret = iio_push_to_buffer(buf, data); | |
1408 | if (ret < 0) | |
1409 | return ret; | |
1410 | } | |
1411 | ||
1412 | return 0; | |
1413 | } | |
1414 | EXPORT_SYMBOL_GPL(iio_push_to_buffers); | |
1415 | ||
9e69c935 LPC |
1416 | /** |
1417 | * iio_buffer_release() - Free a buffer's resources | |
1418 | * @ref: Pointer to the kref embedded in the iio_buffer struct | |
1419 | * | |
1420 | * This function is called when the last reference to the buffer has been | |
1421 | * dropped. It will typically free all resources allocated by the buffer. Do not | |
1422 | * call this function manually, always use iio_buffer_put() when done using a | |
1423 | * buffer. | |
1424 | */ | |
1425 | static void iio_buffer_release(struct kref *ref) | |
1426 | { | |
1427 | struct iio_buffer *buffer = container_of(ref, struct iio_buffer, ref); | |
1428 | ||
1429 | buffer->access->release(buffer); | |
1430 | } | |
1431 | ||
1432 | /** | |
1433 | * iio_buffer_get() - Grab a reference to the buffer | |
1434 | * @buffer: The buffer to grab a reference for, may be NULL | |
1435 | * | |
1436 | * Returns the pointer to the buffer that was passed into the function. | |
1437 | */ | |
1438 | struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer) | |
1439 | { | |
1440 | if (buffer) | |
1441 | kref_get(&buffer->ref); | |
1442 | ||
1443 | return buffer; | |
1444 | } | |
1445 | EXPORT_SYMBOL_GPL(iio_buffer_get); | |
1446 | ||
1447 | /** | |
1448 | * iio_buffer_put() - Release the reference to the buffer | |
1449 | * @buffer: The buffer to release the reference for, may be NULL | |
1450 | */ | |
1451 | void iio_buffer_put(struct iio_buffer *buffer) | |
1452 | { | |
1453 | if (buffer) | |
1454 | kref_put(&buffer->ref, iio_buffer_release); | |
1455 | } | |
1456 | EXPORT_SYMBOL_GPL(iio_buffer_put); | |
2b827ad5 JC |
1457 | |
1458 | /** | |
1459 | * iio_device_attach_buffer - Attach a buffer to a IIO device | |
1460 | * @indio_dev: The device the buffer should be attached to | |
1461 | * @buffer: The buffer to attach to the device | |
1462 | * | |
1463 | * This function attaches a buffer to a IIO device. The buffer stays attached to | |
1464 | * the device until the device is freed. The function should only be called at | |
1465 | * most once per device. | |
1466 | */ | |
1467 | void iio_device_attach_buffer(struct iio_dev *indio_dev, | |
1468 | struct iio_buffer *buffer) | |
1469 | { | |
1470 | indio_dev->buffer = iio_buffer_get(buffer); | |
1471 | } | |
1472 | EXPORT_SYMBOL_GPL(iio_device_attach_buffer); |