Commit | Line | Data |
---|---|---|
7026ea4b JC |
1 | /* The industrial I/O core |
2 | * | |
3 | * Copyright (c) 2008 Jonathan Cameron | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify it | |
6 | * under the terms of the GNU General Public License version 2 as published by | |
7 | * the Free Software Foundation. | |
8 | * | |
14555b14 | 9 | * Handling of buffer allocation / resizing. |
7026ea4b JC |
10 | * |
11 | * | |
12 | * Things to look at here. | |
13 | * - Better memory allocation techniques? | |
14 | * - Alternative access techniques? | |
15 | */ | |
16 | #include <linux/kernel.h> | |
8e336a72 | 17 | #include <linux/export.h> |
7026ea4b | 18 | #include <linux/device.h> |
7026ea4b | 19 | #include <linux/fs.h> |
7026ea4b | 20 | #include <linux/cdev.h> |
5a0e3ad6 | 21 | #include <linux/slab.h> |
a7348347 | 22 | #include <linux/poll.h> |
d2f0a48f | 23 | #include <linux/sched.h> |
7026ea4b | 24 | |
06458e27 | 25 | #include <linux/iio/iio.h> |
df9c1c42 | 26 | #include "iio_core.h" |
06458e27 JC |
27 | #include <linux/iio/sysfs.h> |
28 | #include <linux/iio/buffer.h> | |
7026ea4b | 29 | |
8310b86c JC |
30 | static const char * const iio_endian_prefix[] = { |
31 | [IIO_BE] = "be", | |
32 | [IIO_LE] = "le", | |
33 | }; | |
7026ea4b | 34 | |
705ee2c9 | 35 | static bool iio_buffer_is_active(struct iio_buffer *buf) |
84b36ce5 | 36 | { |
705ee2c9 | 37 | return !list_empty(&buf->buffer_list); |
84b36ce5 JC |
38 | } |
39 | ||
37d34556 | 40 | static size_t iio_buffer_data_available(struct iio_buffer *buf) |
647cc7b9 | 41 | { |
9dd4694d | 42 | return buf->access->data_available(buf); |
647cc7b9 LPC |
43 | } |
44 | ||
f4f4673b OP |
45 | static int iio_buffer_flush_hwfifo(struct iio_dev *indio_dev, |
46 | struct iio_buffer *buf, size_t required) | |
47 | { | |
48 | if (!indio_dev->info->hwfifo_flush_to_buffer) | |
49 | return -ENODEV; | |
50 | ||
51 | return indio_dev->info->hwfifo_flush_to_buffer(indio_dev, required); | |
52 | } | |
53 | ||
37d34556 | 54 | static bool iio_buffer_ready(struct iio_dev *indio_dev, struct iio_buffer *buf, |
f4f4673b | 55 | size_t to_wait, int to_flush) |
37d34556 | 56 | { |
f4f4673b OP |
57 | size_t avail; |
58 | int flushed = 0; | |
59 | ||
37d34556 JC |
60 | /* wakeup if the device was unregistered */ |
61 | if (!indio_dev->info) | |
62 | return true; | |
63 | ||
64 | /* drain the buffer if it was disabled */ | |
f4f4673b | 65 | if (!iio_buffer_is_active(buf)) { |
37d34556 | 66 | to_wait = min_t(size_t, to_wait, 1); |
f4f4673b OP |
67 | to_flush = 0; |
68 | } | |
69 | ||
70 | avail = iio_buffer_data_available(buf); | |
37d34556 | 71 | |
f4f4673b OP |
72 | if (avail >= to_wait) { |
73 | /* force a flush for non-blocking reads */ | |
c6f67a1f OP |
74 | if (!to_wait && avail < to_flush) |
75 | iio_buffer_flush_hwfifo(indio_dev, buf, | |
76 | to_flush - avail); | |
f4f4673b OP |
77 | return true; |
78 | } | |
79 | ||
80 | if (to_flush) | |
81 | flushed = iio_buffer_flush_hwfifo(indio_dev, buf, | |
82 | to_wait - avail); | |
83 | if (flushed <= 0) | |
84 | return false; | |
85 | ||
86 | if (avail + flushed >= to_wait) | |
37d34556 JC |
87 | return true; |
88 | ||
89 | return false; | |
90 | } | |
91 | ||
7026ea4b | 92 | /** |
14555b14 | 93 | * iio_buffer_read_first_n_outer() - chrdev read for buffer access |
0123635a CO |
94 | * @filp: File structure pointer for the char device |
95 | * @buf: Destination buffer for iio buffer read | |
96 | * @n: First n bytes to read | |
97 | * @f_ps: Long offset provided by the user as a seek position | |
7026ea4b | 98 | * |
14555b14 JC |
99 | * This function relies on all buffer implementations having an |
100 | * iio_buffer as their first element. | |
0123635a CO |
101 | * |
102 | * Return: negative values corresponding to error codes or ret != 0 | |
103 | * for ending the reading activity | |
7026ea4b | 104 | **/ |
14555b14 JC |
105 | ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf, |
106 | size_t n, loff_t *f_ps) | |
7026ea4b | 107 | { |
1aa04278 | 108 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 109 | struct iio_buffer *rb = indio_dev->buffer; |
fcf68f3c | 110 | DEFINE_WAIT_FUNC(wait, woken_wake_function); |
37d34556 | 111 | size_t datum_size; |
c6f67a1f | 112 | size_t to_wait; |
5dba4b14 | 113 | int ret = 0; |
d5857d65 | 114 | |
f18e7a06 LPC |
115 | if (!indio_dev->info) |
116 | return -ENODEV; | |
117 | ||
96e00f11 | 118 | if (!rb || !rb->access->read_first_n) |
7026ea4b | 119 | return -EINVAL; |
ee551a10 | 120 | |
37d34556 JC |
121 | datum_size = rb->bytes_per_datum; |
122 | ||
123 | /* | |
124 | * If datum_size is 0 there will never be anything to read from the | |
125 | * buffer, so signal end of file now. | |
126 | */ | |
127 | if (!datum_size) | |
128 | return 0; | |
129 | ||
c6f67a1f OP |
130 | if (filp->f_flags & O_NONBLOCK) |
131 | to_wait = 0; | |
132 | else | |
133 | to_wait = min_t(size_t, n / datum_size, rb->watermark); | |
37d34556 | 134 | |
fcf68f3c | 135 | add_wait_queue(&rb->pollq, &wait); |
ee551a10 | 136 | do { |
fcf68f3c BN |
137 | if (!indio_dev->info) { |
138 | ret = -ENODEV; | |
139 | break; | |
140 | } | |
141 | ||
142 | if (!iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size)) { | |
143 | if (signal_pending(current)) { | |
144 | ret = -ERESTARTSYS; | |
145 | break; | |
146 | } | |
147 | ||
148 | wait_woken(&wait, TASK_INTERRUPTIBLE, | |
149 | MAX_SCHEDULE_TIMEOUT); | |
150 | continue; | |
151 | } | |
ee551a10 LPC |
152 | |
153 | ret = rb->access->read_first_n(rb, n, buf); | |
154 | if (ret == 0 && (filp->f_flags & O_NONBLOCK)) | |
155 | ret = -EAGAIN; | |
5dba4b14 | 156 | } while (ret == 0); |
fcf68f3c | 157 | remove_wait_queue(&rb->pollq, &wait); |
ee551a10 LPC |
158 | |
159 | return ret; | |
7026ea4b JC |
160 | } |
161 | ||
a7348347 | 162 | /** |
14555b14 | 163 | * iio_buffer_poll() - poll the buffer to find out if it has data |
0123635a CO |
164 | * @filp: File structure pointer for device access |
165 | * @wait: Poll table structure pointer for which the driver adds | |
166 | * a wait queue | |
167 | * | |
168 | * Return: (POLLIN | POLLRDNORM) if data is available for reading | |
169 | * or 0 for other cases | |
a7348347 | 170 | */ |
14555b14 JC |
171 | unsigned int iio_buffer_poll(struct file *filp, |
172 | struct poll_table_struct *wait) | |
a7348347 | 173 | { |
1aa04278 | 174 | struct iio_dev *indio_dev = filp->private_data; |
14555b14 | 175 | struct iio_buffer *rb = indio_dev->buffer; |
a7348347 | 176 | |
f18e7a06 | 177 | if (!indio_dev->info) |
1bdc0293 | 178 | return 0; |
f18e7a06 | 179 | |
a7348347 | 180 | poll_wait(filp, &rb->pollq, wait); |
f4f4673b | 181 | if (iio_buffer_ready(indio_dev, rb, rb->watermark, 0)) |
a7348347 | 182 | return POLLIN | POLLRDNORM; |
8d213f24 | 183 | return 0; |
a7348347 JC |
184 | } |
185 | ||
d2f0a48f LPC |
186 | /** |
187 | * iio_buffer_wakeup_poll - Wakes up the buffer waitqueue | |
188 | * @indio_dev: The IIO device | |
189 | * | |
190 | * Wakes up the event waitqueue used for poll(). Should usually | |
191 | * be called when the device is unregistered. | |
192 | */ | |
193 | void iio_buffer_wakeup_poll(struct iio_dev *indio_dev) | |
194 | { | |
195 | if (!indio_dev->buffer) | |
196 | return; | |
197 | ||
198 | wake_up(&indio_dev->buffer->pollq); | |
199 | } | |
200 | ||
f79a9098 | 201 | void iio_buffer_init(struct iio_buffer *buffer) |
7026ea4b | 202 | { |
5ada4ea9 | 203 | INIT_LIST_HEAD(&buffer->demux_list); |
705ee2c9 | 204 | INIT_LIST_HEAD(&buffer->buffer_list); |
14555b14 | 205 | init_waitqueue_head(&buffer->pollq); |
9e69c935 | 206 | kref_init(&buffer->ref); |
4a605357 LPC |
207 | if (!buffer->watermark) |
208 | buffer->watermark = 1; | |
7026ea4b | 209 | } |
14555b14 | 210 | EXPORT_SYMBOL(iio_buffer_init); |
7026ea4b | 211 | |
1d892719 | 212 | static ssize_t iio_show_scan_index(struct device *dev, |
8d213f24 JC |
213 | struct device_attribute *attr, |
214 | char *buf) | |
1d892719 | 215 | { |
8d213f24 | 216 | return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index); |
1d892719 JC |
217 | } |
218 | ||
219 | static ssize_t iio_show_fixed_type(struct device *dev, | |
220 | struct device_attribute *attr, | |
221 | char *buf) | |
222 | { | |
223 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); | |
8310b86c JC |
224 | u8 type = this_attr->c->scan_type.endianness; |
225 | ||
226 | if (type == IIO_CPU) { | |
9d5d1153 JC |
227 | #ifdef __LITTLE_ENDIAN |
228 | type = IIO_LE; | |
229 | #else | |
230 | type = IIO_BE; | |
231 | #endif | |
8310b86c | 232 | } |
0ee8546a SP |
233 | if (this_attr->c->scan_type.repeat > 1) |
234 | return sprintf(buf, "%s:%c%d/%dX%d>>%u\n", | |
235 | iio_endian_prefix[type], | |
236 | this_attr->c->scan_type.sign, | |
237 | this_attr->c->scan_type.realbits, | |
238 | this_attr->c->scan_type.storagebits, | |
239 | this_attr->c->scan_type.repeat, | |
240 | this_attr->c->scan_type.shift); | |
241 | else | |
242 | return sprintf(buf, "%s:%c%d/%d>>%u\n", | |
8310b86c | 243 | iio_endian_prefix[type], |
1d892719 JC |
244 | this_attr->c->scan_type.sign, |
245 | this_attr->c->scan_type.realbits, | |
246 | this_attr->c->scan_type.storagebits, | |
247 | this_attr->c->scan_type.shift); | |
248 | } | |
249 | ||
8d213f24 JC |
250 | static ssize_t iio_scan_el_show(struct device *dev, |
251 | struct device_attribute *attr, | |
252 | char *buf) | |
253 | { | |
254 | int ret; | |
e53f5ac5 | 255 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 256 | |
2076a20f AB |
257 | /* Ensure ret is 0 or 1. */ |
258 | ret = !!test_bit(to_iio_dev_attr(attr)->address, | |
5ada4ea9 JC |
259 | indio_dev->buffer->scan_mask); |
260 | ||
8d213f24 JC |
261 | return sprintf(buf, "%d\n", ret); |
262 | } | |
263 | ||
217a5cf0 LPC |
264 | /* Note NULL used as error indicator as it doesn't make sense. */ |
265 | static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks, | |
266 | unsigned int masklength, | |
1e1ec286 LPC |
267 | const unsigned long *mask, |
268 | bool strict) | |
217a5cf0 LPC |
269 | { |
270 | if (bitmap_empty(mask, masklength)) | |
271 | return NULL; | |
272 | while (*av_masks) { | |
1e1ec286 LPC |
273 | if (strict) { |
274 | if (bitmap_equal(mask, av_masks, masklength)) | |
275 | return av_masks; | |
276 | } else { | |
277 | if (bitmap_subset(mask, av_masks, masklength)) | |
278 | return av_masks; | |
279 | } | |
217a5cf0 LPC |
280 | av_masks += BITS_TO_LONGS(masklength); |
281 | } | |
282 | return NULL; | |
283 | } | |
284 | ||
285 | static bool iio_validate_scan_mask(struct iio_dev *indio_dev, | |
286 | const unsigned long *mask) | |
287 | { | |
288 | if (!indio_dev->setup_ops->validate_scan_mask) | |
289 | return true; | |
290 | ||
291 | return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask); | |
292 | } | |
293 | ||
294 | /** | |
295 | * iio_scan_mask_set() - set particular bit in the scan mask | |
296 | * @indio_dev: the iio device | |
297 | * @buffer: the buffer whose scan mask we are interested in | |
298 | * @bit: the bit to be set. | |
299 | * | |
300 | * Note that at this point we have no way of knowing what other | |
301 | * buffers might request, hence this code only verifies that the | |
302 | * individual buffers request is plausible. | |
303 | */ | |
304 | static int iio_scan_mask_set(struct iio_dev *indio_dev, | |
305 | struct iio_buffer *buffer, int bit) | |
306 | { | |
307 | const unsigned long *mask; | |
308 | unsigned long *trialmask; | |
309 | ||
310 | trialmask = kmalloc(sizeof(*trialmask)* | |
311 | BITS_TO_LONGS(indio_dev->masklength), | |
312 | GFP_KERNEL); | |
313 | ||
314 | if (trialmask == NULL) | |
315 | return -ENOMEM; | |
316 | if (!indio_dev->masklength) { | |
231bfe53 | 317 | WARN(1, "Trying to set scanmask prior to registering buffer\n"); |
217a5cf0 LPC |
318 | goto err_invalid_mask; |
319 | } | |
320 | bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength); | |
321 | set_bit(bit, trialmask); | |
322 | ||
323 | if (!iio_validate_scan_mask(indio_dev, trialmask)) | |
324 | goto err_invalid_mask; | |
325 | ||
326 | if (indio_dev->available_scan_masks) { | |
327 | mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
328 | indio_dev->masklength, | |
1e1ec286 | 329 | trialmask, false); |
217a5cf0 LPC |
330 | if (!mask) |
331 | goto err_invalid_mask; | |
332 | } | |
333 | bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength); | |
334 | ||
335 | kfree(trialmask); | |
336 | ||
337 | return 0; | |
338 | ||
339 | err_invalid_mask: | |
340 | kfree(trialmask); | |
341 | return -EINVAL; | |
342 | } | |
343 | ||
14555b14 | 344 | static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit) |
8d213f24 | 345 | { |
14555b14 | 346 | clear_bit(bit, buffer->scan_mask); |
8d213f24 JC |
347 | return 0; |
348 | } | |
349 | ||
350 | static ssize_t iio_scan_el_store(struct device *dev, | |
351 | struct device_attribute *attr, | |
352 | const char *buf, | |
353 | size_t len) | |
354 | { | |
a714af27 | 355 | int ret; |
8d213f24 | 356 | bool state; |
e53f5ac5 | 357 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 358 | struct iio_buffer *buffer = indio_dev->buffer; |
8d213f24 JC |
359 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
360 | ||
a714af27 JC |
361 | ret = strtobool(buf, &state); |
362 | if (ret < 0) | |
363 | return ret; | |
8d213f24 | 364 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 365 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
366 | ret = -EBUSY; |
367 | goto error_ret; | |
368 | } | |
f79a9098 | 369 | ret = iio_scan_mask_query(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
370 | if (ret < 0) |
371 | goto error_ret; | |
372 | if (!state && ret) { | |
14555b14 | 373 | ret = iio_scan_mask_clear(buffer, this_attr->address); |
8d213f24 JC |
374 | if (ret) |
375 | goto error_ret; | |
376 | } else if (state && !ret) { | |
f79a9098 | 377 | ret = iio_scan_mask_set(indio_dev, buffer, this_attr->address); |
8d213f24 JC |
378 | if (ret) |
379 | goto error_ret; | |
380 | } | |
381 | ||
382 | error_ret: | |
383 | mutex_unlock(&indio_dev->mlock); | |
384 | ||
5a2a6e11 | 385 | return ret < 0 ? ret : len; |
8d213f24 JC |
386 | |
387 | } | |
388 | ||
389 | static ssize_t iio_scan_el_ts_show(struct device *dev, | |
390 | struct device_attribute *attr, | |
391 | char *buf) | |
392 | { | |
e53f5ac5 | 393 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
f8c6f4e9 | 394 | return sprintf(buf, "%d\n", indio_dev->buffer->scan_timestamp); |
8d213f24 JC |
395 | } |
396 | ||
397 | static ssize_t iio_scan_el_ts_store(struct device *dev, | |
398 | struct device_attribute *attr, | |
399 | const char *buf, | |
400 | size_t len) | |
401 | { | |
a714af27 | 402 | int ret; |
e53f5ac5 | 403 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
8d213f24 | 404 | bool state; |
1aa04278 | 405 | |
a714af27 JC |
406 | ret = strtobool(buf, &state); |
407 | if (ret < 0) | |
408 | return ret; | |
409 | ||
8d213f24 | 410 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 411 | if (iio_buffer_is_active(indio_dev->buffer)) { |
8d213f24 JC |
412 | ret = -EBUSY; |
413 | goto error_ret; | |
414 | } | |
14555b14 | 415 | indio_dev->buffer->scan_timestamp = state; |
8d213f24 JC |
416 | error_ret: |
417 | mutex_unlock(&indio_dev->mlock); | |
418 | ||
419 | return ret ? ret : len; | |
420 | } | |
421 | ||
14555b14 JC |
422 | static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev, |
423 | const struct iio_chan_spec *chan) | |
1d892719 | 424 | { |
26d25ae3 | 425 | int ret, attrcount = 0; |
14555b14 | 426 | struct iio_buffer *buffer = indio_dev->buffer; |
1d892719 | 427 | |
26d25ae3 | 428 | ret = __iio_add_chan_devattr("index", |
1d892719 JC |
429 | chan, |
430 | &iio_show_scan_index, | |
431 | NULL, | |
432 | 0, | |
3704432f | 433 | IIO_SEPARATE, |
1aa04278 | 434 | &indio_dev->dev, |
14555b14 | 435 | &buffer->scan_el_dev_attr_list); |
1d892719 | 436 | if (ret) |
92825ff9 | 437 | return ret; |
26d25ae3 JC |
438 | attrcount++; |
439 | ret = __iio_add_chan_devattr("type", | |
1d892719 JC |
440 | chan, |
441 | &iio_show_fixed_type, | |
442 | NULL, | |
443 | 0, | |
444 | 0, | |
1aa04278 | 445 | &indio_dev->dev, |
14555b14 | 446 | &buffer->scan_el_dev_attr_list); |
1d892719 | 447 | if (ret) |
92825ff9 | 448 | return ret; |
26d25ae3 | 449 | attrcount++; |
a88b3ebc | 450 | if (chan->type != IIO_TIMESTAMP) |
26d25ae3 | 451 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
452 | chan, |
453 | &iio_scan_el_show, | |
454 | &iio_scan_el_store, | |
455 | chan->scan_index, | |
456 | 0, | |
1aa04278 | 457 | &indio_dev->dev, |
14555b14 | 458 | &buffer->scan_el_dev_attr_list); |
a88b3ebc | 459 | else |
26d25ae3 | 460 | ret = __iio_add_chan_devattr("en", |
a88b3ebc JC |
461 | chan, |
462 | &iio_scan_el_ts_show, | |
463 | &iio_scan_el_ts_store, | |
464 | chan->scan_index, | |
465 | 0, | |
1aa04278 | 466 | &indio_dev->dev, |
14555b14 | 467 | &buffer->scan_el_dev_attr_list); |
9572588c | 468 | if (ret) |
92825ff9 | 469 | return ret; |
26d25ae3 JC |
470 | attrcount++; |
471 | ret = attrcount; | |
1d892719 JC |
472 | return ret; |
473 | } | |
474 | ||
08e7e0ad LPC |
475 | static ssize_t iio_buffer_read_length(struct device *dev, |
476 | struct device_attribute *attr, | |
477 | char *buf) | |
7026ea4b | 478 | { |
e53f5ac5 | 479 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 480 | struct iio_buffer *buffer = indio_dev->buffer; |
7026ea4b | 481 | |
37495660 | 482 | return sprintf(buf, "%d\n", buffer->length); |
7026ea4b | 483 | } |
7026ea4b | 484 | |
08e7e0ad LPC |
485 | static ssize_t iio_buffer_write_length(struct device *dev, |
486 | struct device_attribute *attr, | |
487 | const char *buf, size_t len) | |
7026ea4b | 488 | { |
e53f5ac5 | 489 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
14555b14 | 490 | struct iio_buffer *buffer = indio_dev->buffer; |
948ad205 LPC |
491 | unsigned int val; |
492 | int ret; | |
8d213f24 | 493 | |
948ad205 | 494 | ret = kstrtouint(buf, 10, &val); |
7026ea4b JC |
495 | if (ret) |
496 | return ret; | |
497 | ||
37495660 LPC |
498 | if (val == buffer->length) |
499 | return len; | |
7026ea4b | 500 | |
e38c79e0 | 501 | mutex_lock(&indio_dev->mlock); |
705ee2c9 | 502 | if (iio_buffer_is_active(indio_dev->buffer)) { |
e38c79e0 LPC |
503 | ret = -EBUSY; |
504 | } else { | |
8d92db28 | 505 | buffer->access->set_length(buffer, val); |
e38c79e0 | 506 | ret = 0; |
7026ea4b | 507 | } |
37d34556 JC |
508 | if (ret) |
509 | goto out; | |
510 | if (buffer->length && buffer->length < buffer->watermark) | |
511 | buffer->watermark = buffer->length; | |
512 | out: | |
e38c79e0 | 513 | mutex_unlock(&indio_dev->mlock); |
7026ea4b | 514 | |
e38c79e0 | 515 | return ret ? ret : len; |
7026ea4b | 516 | } |
7026ea4b | 517 | |
08e7e0ad LPC |
518 | static ssize_t iio_buffer_show_enable(struct device *dev, |
519 | struct device_attribute *attr, | |
520 | char *buf) | |
7026ea4b | 521 | { |
e53f5ac5 | 522 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
705ee2c9 | 523 | return sprintf(buf, "%d\n", iio_buffer_is_active(indio_dev->buffer)); |
7026ea4b | 524 | } |
7026ea4b | 525 | |
182b4905 LPC |
526 | static unsigned int iio_storage_bytes_for_si(struct iio_dev *indio_dev, |
527 | unsigned int scan_index) | |
528 | { | |
529 | const struct iio_chan_spec *ch; | |
530 | unsigned int bytes; | |
531 | ||
532 | ch = iio_find_channel_from_si(indio_dev, scan_index); | |
533 | bytes = ch->scan_type.storagebits / 8; | |
534 | if (ch->scan_type.repeat > 1) | |
535 | bytes *= ch->scan_type.repeat; | |
536 | return bytes; | |
537 | } | |
538 | ||
539 | static unsigned int iio_storage_bytes_for_timestamp(struct iio_dev *indio_dev) | |
540 | { | |
541 | return iio_storage_bytes_for_si(indio_dev, | |
542 | indio_dev->scan_index_timestamp); | |
543 | } | |
544 | ||
183f4173 PM |
545 | static int iio_compute_scan_bytes(struct iio_dev *indio_dev, |
546 | const unsigned long *mask, bool timestamp) | |
959d2952 | 547 | { |
959d2952 JC |
548 | unsigned bytes = 0; |
549 | int length, i; | |
959d2952 JC |
550 | |
551 | /* How much space will the demuxed element take? */ | |
6b3b58ed | 552 | for_each_set_bit(i, mask, |
959d2952 | 553 | indio_dev->masklength) { |
182b4905 | 554 | length = iio_storage_bytes_for_si(indio_dev, i); |
959d2952 JC |
555 | bytes = ALIGN(bytes, length); |
556 | bytes += length; | |
557 | } | |
182b4905 | 558 | |
6b3b58ed | 559 | if (timestamp) { |
182b4905 | 560 | length = iio_storage_bytes_for_timestamp(indio_dev); |
959d2952 JC |
561 | bytes = ALIGN(bytes, length); |
562 | bytes += length; | |
563 | } | |
6b3b58ed JC |
564 | return bytes; |
565 | } | |
566 | ||
9e69c935 LPC |
567 | static void iio_buffer_activate(struct iio_dev *indio_dev, |
568 | struct iio_buffer *buffer) | |
569 | { | |
570 | iio_buffer_get(buffer); | |
571 | list_add(&buffer->buffer_list, &indio_dev->buffer_list); | |
572 | } | |
573 | ||
574 | static void iio_buffer_deactivate(struct iio_buffer *buffer) | |
575 | { | |
576 | list_del_init(&buffer->buffer_list); | |
37d34556 | 577 | wake_up_interruptible(&buffer->pollq); |
9e69c935 LPC |
578 | iio_buffer_put(buffer); |
579 | } | |
580 | ||
1250186a LPC |
581 | static void iio_buffer_deactivate_all(struct iio_dev *indio_dev) |
582 | { | |
583 | struct iio_buffer *buffer, *_buffer; | |
584 | ||
585 | list_for_each_entry_safe(buffer, _buffer, | |
586 | &indio_dev->buffer_list, buffer_list) | |
587 | iio_buffer_deactivate(buffer); | |
588 | } | |
589 | ||
e18a2ad4 LPC |
590 | static int iio_buffer_enable(struct iio_buffer *buffer, |
591 | struct iio_dev *indio_dev) | |
592 | { | |
593 | if (!buffer->access->enable) | |
594 | return 0; | |
595 | return buffer->access->enable(buffer, indio_dev); | |
596 | } | |
597 | ||
598 | static int iio_buffer_disable(struct iio_buffer *buffer, | |
599 | struct iio_dev *indio_dev) | |
600 | { | |
601 | if (!buffer->access->disable) | |
602 | return 0; | |
603 | return buffer->access->disable(buffer, indio_dev); | |
604 | } | |
605 | ||
8e050996 LPC |
606 | static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev, |
607 | struct iio_buffer *buffer) | |
608 | { | |
609 | unsigned int bytes; | |
610 | ||
611 | if (!buffer->access->set_bytes_per_datum) | |
612 | return; | |
613 | ||
614 | bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask, | |
615 | buffer->scan_timestamp); | |
616 | ||
617 | buffer->access->set_bytes_per_datum(buffer, bytes); | |
618 | } | |
619 | ||
fcc1b2f5 LPC |
620 | static int iio_buffer_request_update(struct iio_dev *indio_dev, |
621 | struct iio_buffer *buffer) | |
622 | { | |
623 | int ret; | |
624 | ||
625 | iio_buffer_update_bytes_per_datum(indio_dev, buffer); | |
626 | if (buffer->access->request_update) { | |
627 | ret = buffer->access->request_update(buffer); | |
628 | if (ret) { | |
629 | dev_dbg(&indio_dev->dev, | |
630 | "Buffer not started: buffer parameter update failed (%d)\n", | |
631 | ret); | |
632 | return ret; | |
633 | } | |
634 | } | |
635 | ||
636 | return 0; | |
637 | } | |
638 | ||
248be5aa LPC |
639 | static void iio_free_scan_mask(struct iio_dev *indio_dev, |
640 | const unsigned long *mask) | |
641 | { | |
642 | /* If the mask is dynamically allocated free it, otherwise do nothing */ | |
643 | if (!indio_dev->available_scan_masks) | |
644 | kfree(mask); | |
645 | } | |
646 | ||
6e509c4d LPC |
647 | struct iio_device_config { |
648 | unsigned int mode; | |
f0566c0c | 649 | unsigned int watermark; |
6e509c4d LPC |
650 | const unsigned long *scan_mask; |
651 | unsigned int scan_bytes; | |
652 | bool scan_timestamp; | |
653 | }; | |
654 | ||
655 | static int iio_verify_update(struct iio_dev *indio_dev, | |
656 | struct iio_buffer *insert_buffer, struct iio_buffer *remove_buffer, | |
657 | struct iio_device_config *config) | |
658 | { | |
659 | unsigned long *compound_mask; | |
660 | const unsigned long *scan_mask; | |
1e1ec286 | 661 | bool strict_scanmask = false; |
6e509c4d LPC |
662 | struct iio_buffer *buffer; |
663 | bool scan_timestamp; | |
225d59ad | 664 | unsigned int modes; |
6e509c4d LPC |
665 | |
666 | memset(config, 0, sizeof(*config)); | |
1bef2c1d | 667 | config->watermark = ~0; |
6e509c4d LPC |
668 | |
669 | /* | |
670 | * If there is just one buffer and we are removing it there is nothing | |
671 | * to verify. | |
672 | */ | |
673 | if (remove_buffer && !insert_buffer && | |
674 | list_is_singular(&indio_dev->buffer_list)) | |
675 | return 0; | |
676 | ||
225d59ad LPC |
677 | modes = indio_dev->modes; |
678 | ||
679 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
680 | if (buffer == remove_buffer) | |
681 | continue; | |
682 | modes &= buffer->access->modes; | |
f0566c0c | 683 | config->watermark = min(config->watermark, buffer->watermark); |
225d59ad LPC |
684 | } |
685 | ||
f0566c0c | 686 | if (insert_buffer) { |
225d59ad | 687 | modes &= insert_buffer->access->modes; |
f0566c0c LPC |
688 | config->watermark = min(config->watermark, |
689 | insert_buffer->watermark); | |
690 | } | |
225d59ad | 691 | |
6e509c4d | 692 | /* Definitely possible for devices to support both of these. */ |
225d59ad | 693 | if ((modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) { |
6e509c4d | 694 | config->mode = INDIO_BUFFER_TRIGGERED; |
225d59ad | 695 | } else if (modes & INDIO_BUFFER_HARDWARE) { |
1e1ec286 LPC |
696 | /* |
697 | * Keep things simple for now and only allow a single buffer to | |
698 | * be connected in hardware mode. | |
699 | */ | |
700 | if (insert_buffer && !list_empty(&indio_dev->buffer_list)) | |
701 | return -EINVAL; | |
6e509c4d | 702 | config->mode = INDIO_BUFFER_HARDWARE; |
1e1ec286 | 703 | strict_scanmask = true; |
225d59ad | 704 | } else if (modes & INDIO_BUFFER_SOFTWARE) { |
6e509c4d LPC |
705 | config->mode = INDIO_BUFFER_SOFTWARE; |
706 | } else { | |
707 | /* Can only occur on first buffer */ | |
708 | if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) | |
709 | dev_dbg(&indio_dev->dev, "Buffer not started: no trigger\n"); | |
710 | return -EINVAL; | |
711 | } | |
712 | ||
713 | /* What scan mask do we actually have? */ | |
714 | compound_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), | |
715 | sizeof(long), GFP_KERNEL); | |
716 | if (compound_mask == NULL) | |
717 | return -ENOMEM; | |
718 | ||
719 | scan_timestamp = false; | |
720 | ||
721 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
722 | if (buffer == remove_buffer) | |
723 | continue; | |
724 | bitmap_or(compound_mask, compound_mask, buffer->scan_mask, | |
725 | indio_dev->masklength); | |
726 | scan_timestamp |= buffer->scan_timestamp; | |
727 | } | |
728 | ||
729 | if (insert_buffer) { | |
730 | bitmap_or(compound_mask, compound_mask, | |
731 | insert_buffer->scan_mask, indio_dev->masklength); | |
732 | scan_timestamp |= insert_buffer->scan_timestamp; | |
733 | } | |
734 | ||
735 | if (indio_dev->available_scan_masks) { | |
736 | scan_mask = iio_scan_mask_match(indio_dev->available_scan_masks, | |
737 | indio_dev->masklength, | |
1e1ec286 LPC |
738 | compound_mask, |
739 | strict_scanmask); | |
6e509c4d LPC |
740 | kfree(compound_mask); |
741 | if (scan_mask == NULL) | |
742 | return -EINVAL; | |
743 | } else { | |
744 | scan_mask = compound_mask; | |
745 | } | |
746 | ||
747 | config->scan_bytes = iio_compute_scan_bytes(indio_dev, | |
748 | scan_mask, scan_timestamp); | |
749 | config->scan_mask = scan_mask; | |
750 | config->scan_timestamp = scan_timestamp; | |
751 | ||
752 | return 0; | |
753 | } | |
754 | ||
623d74e3 LPC |
755 | static int iio_enable_buffers(struct iio_dev *indio_dev, |
756 | struct iio_device_config *config) | |
6b3b58ed | 757 | { |
e18a2ad4 | 758 | struct iio_buffer *buffer; |
84b36ce5 | 759 | int ret; |
fcc1b2f5 | 760 | |
623d74e3 LPC |
761 | indio_dev->active_scan_mask = config->scan_mask; |
762 | indio_dev->scan_timestamp = config->scan_timestamp; | |
763 | indio_dev->scan_bytes = config->scan_bytes; | |
aff1eb4e | 764 | |
5ada4ea9 JC |
765 | iio_update_demux(indio_dev); |
766 | ||
84b36ce5 JC |
767 | /* Wind up again */ |
768 | if (indio_dev->setup_ops->preenable) { | |
769 | ret = indio_dev->setup_ops->preenable(indio_dev); | |
770 | if (ret) { | |
63223c5f | 771 | dev_dbg(&indio_dev->dev, |
bec1889d | 772 | "Buffer not started: buffer preenable failed (%d)\n", ret); |
623d74e3 | 773 | goto err_undo_config; |
84b36ce5 JC |
774 | } |
775 | } | |
6e509c4d | 776 | |
84b36ce5 JC |
777 | if (indio_dev->info->update_scan_mode) { |
778 | ret = indio_dev->info | |
5ada4ea9 JC |
779 | ->update_scan_mode(indio_dev, |
780 | indio_dev->active_scan_mask); | |
84b36ce5 | 781 | if (ret < 0) { |
63223c5f LPC |
782 | dev_dbg(&indio_dev->dev, |
783 | "Buffer not started: update scan mode failed (%d)\n", | |
784 | ret); | |
623d74e3 | 785 | goto err_run_postdisable; |
84b36ce5 JC |
786 | } |
787 | } | |
6e509c4d | 788 | |
f0566c0c LPC |
789 | if (indio_dev->info->hwfifo_set_watermark) |
790 | indio_dev->info->hwfifo_set_watermark(indio_dev, | |
791 | config->watermark); | |
792 | ||
e18a2ad4 LPC |
793 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { |
794 | ret = iio_buffer_enable(buffer, indio_dev); | |
795 | if (ret) | |
796 | goto err_disable_buffers; | |
797 | } | |
798 | ||
623d74e3 | 799 | indio_dev->currentmode = config->mode; |
84b36ce5 JC |
800 | |
801 | if (indio_dev->setup_ops->postenable) { | |
802 | ret = indio_dev->setup_ops->postenable(indio_dev); | |
803 | if (ret) { | |
63223c5f | 804 | dev_dbg(&indio_dev->dev, |
bec1889d | 805 | "Buffer not started: postenable failed (%d)\n", ret); |
e18a2ad4 | 806 | goto err_disable_buffers; |
84b36ce5 JC |
807 | } |
808 | } | |
809 | ||
6e509c4d | 810 | return 0; |
84b36ce5 | 811 | |
e18a2ad4 LPC |
812 | err_disable_buffers: |
813 | list_for_each_entry_continue_reverse(buffer, &indio_dev->buffer_list, | |
814 | buffer_list) | |
815 | iio_buffer_disable(buffer, indio_dev); | |
623d74e3 | 816 | err_run_postdisable: |
84b36ce5 | 817 | indio_dev->currentmode = INDIO_DIRECT_MODE; |
84b36ce5 JC |
818 | if (indio_dev->setup_ops->postdisable) |
819 | indio_dev->setup_ops->postdisable(indio_dev); | |
623d74e3 LPC |
820 | err_undo_config: |
821 | indio_dev->active_scan_mask = NULL; | |
822 | ||
84b36ce5 | 823 | return ret; |
623d74e3 LPC |
824 | } |
825 | ||
826 | static int iio_disable_buffers(struct iio_dev *indio_dev) | |
827 | { | |
e18a2ad4 | 828 | struct iio_buffer *buffer; |
1250186a LPC |
829 | int ret = 0; |
830 | int ret2; | |
623d74e3 LPC |
831 | |
832 | /* Wind down existing buffers - iff there are any */ | |
833 | if (list_empty(&indio_dev->buffer_list)) | |
834 | return 0; | |
835 | ||
1250186a LPC |
836 | /* |
837 | * If things go wrong at some step in disable we still need to continue | |
838 | * to perform the other steps, otherwise we leave the device in a | |
839 | * inconsistent state. We return the error code for the first error we | |
840 | * encountered. | |
841 | */ | |
842 | ||
623d74e3 | 843 | if (indio_dev->setup_ops->predisable) { |
1250186a LPC |
844 | ret2 = indio_dev->setup_ops->predisable(indio_dev); |
845 | if (ret2 && !ret) | |
846 | ret = ret2; | |
623d74e3 | 847 | } |
e18a2ad4 LPC |
848 | |
849 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
850 | ret2 = iio_buffer_disable(buffer, indio_dev); | |
851 | if (ret2 && !ret) | |
852 | ret = ret2; | |
853 | } | |
623d74e3 LPC |
854 | |
855 | indio_dev->currentmode = INDIO_DIRECT_MODE; | |
856 | ||
857 | if (indio_dev->setup_ops->postdisable) { | |
1250186a LPC |
858 | ret2 = indio_dev->setup_ops->postdisable(indio_dev); |
859 | if (ret2 && !ret) | |
860 | ret = ret2; | |
623d74e3 LPC |
861 | } |
862 | ||
1250186a LPC |
863 | iio_free_scan_mask(indio_dev, indio_dev->active_scan_mask); |
864 | indio_dev->active_scan_mask = NULL; | |
865 | ||
866 | return ret; | |
623d74e3 LPC |
867 | } |
868 | ||
869 | static int __iio_update_buffers(struct iio_dev *indio_dev, | |
870 | struct iio_buffer *insert_buffer, | |
871 | struct iio_buffer *remove_buffer) | |
872 | { | |
623d74e3 | 873 | struct iio_device_config new_config; |
1250186a | 874 | int ret; |
623d74e3 LPC |
875 | |
876 | ret = iio_verify_update(indio_dev, insert_buffer, remove_buffer, | |
877 | &new_config); | |
878 | if (ret) | |
879 | return ret; | |
880 | ||
881 | if (insert_buffer) { | |
882 | ret = iio_buffer_request_update(indio_dev, insert_buffer); | |
883 | if (ret) | |
884 | goto err_free_config; | |
885 | } | |
886 | ||
623d74e3 | 887 | ret = iio_disable_buffers(indio_dev); |
1250186a LPC |
888 | if (ret) |
889 | goto err_deactivate_all; | |
623d74e3 LPC |
890 | |
891 | if (remove_buffer) | |
892 | iio_buffer_deactivate(remove_buffer); | |
893 | if (insert_buffer) | |
894 | iio_buffer_activate(indio_dev, insert_buffer); | |
895 | ||
896 | /* If no buffers in list, we are done */ | |
1250186a | 897 | if (list_empty(&indio_dev->buffer_list)) |
623d74e3 | 898 | return 0; |
623d74e3 LPC |
899 | |
900 | ret = iio_enable_buffers(indio_dev, &new_config); | |
1250186a LPC |
901 | if (ret) |
902 | goto err_deactivate_all; | |
623d74e3 | 903 | |
623d74e3 | 904 | return 0; |
6e509c4d | 905 | |
1250186a LPC |
906 | err_deactivate_all: |
907 | /* | |
908 | * We've already verified that the config is valid earlier. If things go | |
909 | * wrong in either enable or disable the most likely reason is an IO | |
910 | * error from the device. In this case there is no good recovery | |
911 | * strategy. Just make sure to disable everything and leave the device | |
912 | * in a sane state. With a bit of luck the device might come back to | |
913 | * life again later and userspace can try again. | |
914 | */ | |
915 | iio_buffer_deactivate_all(indio_dev); | |
916 | ||
6e509c4d LPC |
917 | err_free_config: |
918 | iio_free_scan_mask(indio_dev, new_config.scan_mask); | |
919 | return ret; | |
84b36ce5 | 920 | } |
a9519456 LPC |
921 | |
922 | int iio_update_buffers(struct iio_dev *indio_dev, | |
923 | struct iio_buffer *insert_buffer, | |
924 | struct iio_buffer *remove_buffer) | |
925 | { | |
926 | int ret; | |
927 | ||
3909fab5 LPC |
928 | if (insert_buffer == remove_buffer) |
929 | return 0; | |
930 | ||
a9519456 LPC |
931 | mutex_lock(&indio_dev->info_exist_lock); |
932 | mutex_lock(&indio_dev->mlock); | |
933 | ||
3909fab5 LPC |
934 | if (insert_buffer && iio_buffer_is_active(insert_buffer)) |
935 | insert_buffer = NULL; | |
936 | ||
937 | if (remove_buffer && !iio_buffer_is_active(remove_buffer)) | |
938 | remove_buffer = NULL; | |
939 | ||
940 | if (!insert_buffer && !remove_buffer) { | |
941 | ret = 0; | |
942 | goto out_unlock; | |
943 | } | |
944 | ||
a9519456 LPC |
945 | if (indio_dev->info == NULL) { |
946 | ret = -ENODEV; | |
947 | goto out_unlock; | |
948 | } | |
949 | ||
950 | ret = __iio_update_buffers(indio_dev, insert_buffer, remove_buffer); | |
951 | ||
952 | out_unlock: | |
953 | mutex_unlock(&indio_dev->mlock); | |
954 | mutex_unlock(&indio_dev->info_exist_lock); | |
955 | ||
956 | return ret; | |
957 | } | |
84b36ce5 JC |
958 | EXPORT_SYMBOL_GPL(iio_update_buffers); |
959 | ||
623d74e3 LPC |
960 | void iio_disable_all_buffers(struct iio_dev *indio_dev) |
961 | { | |
623d74e3 | 962 | iio_disable_buffers(indio_dev); |
1250186a | 963 | iio_buffer_deactivate_all(indio_dev); |
623d74e3 LPC |
964 | } |
965 | ||
08e7e0ad LPC |
966 | static ssize_t iio_buffer_store_enable(struct device *dev, |
967 | struct device_attribute *attr, | |
968 | const char *buf, | |
969 | size_t len) | |
84b36ce5 JC |
970 | { |
971 | int ret; | |
972 | bool requested_state; | |
973 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
84b36ce5 JC |
974 | bool inlist; |
975 | ||
976 | ret = strtobool(buf, &requested_state); | |
977 | if (ret < 0) | |
978 | return ret; | |
979 | ||
980 | mutex_lock(&indio_dev->mlock); | |
981 | ||
982 | /* Find out if it is in the list */ | |
705ee2c9 | 983 | inlist = iio_buffer_is_active(indio_dev->buffer); |
84b36ce5 JC |
984 | /* Already in desired state */ |
985 | if (inlist == requested_state) | |
986 | goto done; | |
987 | ||
988 | if (requested_state) | |
a9519456 | 989 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
990 | indio_dev->buffer, NULL); |
991 | else | |
a9519456 | 992 | ret = __iio_update_buffers(indio_dev, |
84b36ce5 JC |
993 | NULL, indio_dev->buffer); |
994 | ||
84b36ce5 JC |
995 | done: |
996 | mutex_unlock(&indio_dev->mlock); | |
997 | return (ret < 0) ? ret : len; | |
998 | } | |
84b36ce5 | 999 | |
d967cb6b LPC |
1000 | static const char * const iio_scan_elements_group_name = "scan_elements"; |
1001 | ||
37d34556 JC |
1002 | static ssize_t iio_buffer_show_watermark(struct device *dev, |
1003 | struct device_attribute *attr, | |
1004 | char *buf) | |
1005 | { | |
1006 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1007 | struct iio_buffer *buffer = indio_dev->buffer; | |
1008 | ||
1009 | return sprintf(buf, "%u\n", buffer->watermark); | |
1010 | } | |
1011 | ||
1012 | static ssize_t iio_buffer_store_watermark(struct device *dev, | |
1013 | struct device_attribute *attr, | |
1014 | const char *buf, | |
1015 | size_t len) | |
1016 | { | |
1017 | struct iio_dev *indio_dev = dev_to_iio_dev(dev); | |
1018 | struct iio_buffer *buffer = indio_dev->buffer; | |
1019 | unsigned int val; | |
1020 | int ret; | |
1021 | ||
1022 | ret = kstrtouint(buf, 10, &val); | |
1023 | if (ret) | |
1024 | return ret; | |
1025 | if (!val) | |
1026 | return -EINVAL; | |
1027 | ||
1028 | mutex_lock(&indio_dev->mlock); | |
1029 | ||
1030 | if (val > buffer->length) { | |
1031 | ret = -EINVAL; | |
1032 | goto out; | |
1033 | } | |
1034 | ||
1035 | if (iio_buffer_is_active(indio_dev->buffer)) { | |
1036 | ret = -EBUSY; | |
1037 | goto out; | |
1038 | } | |
1039 | ||
1040 | buffer->watermark = val; | |
1041 | out: | |
1042 | mutex_unlock(&indio_dev->mlock); | |
1043 | ||
1044 | return ret ? ret : len; | |
1045 | } | |
1046 | ||
08e7e0ad LPC |
1047 | static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length, |
1048 | iio_buffer_write_length); | |
8d92db28 LPC |
1049 | static struct device_attribute dev_attr_length_ro = __ATTR(length, |
1050 | S_IRUGO, iio_buffer_read_length, NULL); | |
08e7e0ad LPC |
1051 | static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, |
1052 | iio_buffer_show_enable, iio_buffer_store_enable); | |
37d34556 JC |
1053 | static DEVICE_ATTR(watermark, S_IRUGO | S_IWUSR, |
1054 | iio_buffer_show_watermark, iio_buffer_store_watermark); | |
b440655b LPC |
1055 | static struct device_attribute dev_attr_watermark_ro = __ATTR(watermark, |
1056 | S_IRUGO, iio_buffer_show_watermark, NULL); | |
08e7e0ad | 1057 | |
6da9b382 OP |
1058 | static struct attribute *iio_buffer_attrs[] = { |
1059 | &dev_attr_length.attr, | |
1060 | &dev_attr_enable.attr, | |
37d34556 | 1061 | &dev_attr_watermark.attr, |
6da9b382 OP |
1062 | }; |
1063 | ||
d967cb6b LPC |
1064 | int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev) |
1065 | { | |
1066 | struct iio_dev_attr *p; | |
1067 | struct attribute **attr; | |
1068 | struct iio_buffer *buffer = indio_dev->buffer; | |
1069 | int ret, i, attrn, attrcount, attrcount_orig = 0; | |
1070 | const struct iio_chan_spec *channels; | |
1071 | ||
629bc023 LPC |
1072 | channels = indio_dev->channels; |
1073 | if (channels) { | |
1074 | int ml = indio_dev->masklength; | |
1075 | ||
1076 | for (i = 0; i < indio_dev->num_channels; i++) | |
1077 | ml = max(ml, channels[i].scan_index + 1); | |
1078 | indio_dev->masklength = ml; | |
1079 | } | |
1080 | ||
d967cb6b LPC |
1081 | if (!buffer) |
1082 | return 0; | |
1083 | ||
08e7e0ad LPC |
1084 | attrcount = 0; |
1085 | if (buffer->attrs) { | |
1086 | while (buffer->attrs[attrcount] != NULL) | |
1087 | attrcount++; | |
1088 | } | |
1089 | ||
6da9b382 OP |
1090 | attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, |
1091 | sizeof(struct attribute *), GFP_KERNEL); | |
1092 | if (!attr) | |
08e7e0ad LPC |
1093 | return -ENOMEM; |
1094 | ||
6da9b382 OP |
1095 | memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); |
1096 | if (!buffer->access->set_length) | |
1097 | attr[0] = &dev_attr_length_ro.attr; | |
1098 | ||
b440655b LPC |
1099 | if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) |
1100 | attr[2] = &dev_attr_watermark_ro.attr; | |
1101 | ||
08e7e0ad | 1102 | if (buffer->attrs) |
6da9b382 OP |
1103 | memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, |
1104 | sizeof(struct attribute *) * attrcount); | |
1105 | ||
1106 | attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; | |
1107 | ||
1108 | buffer->buffer_group.name = "buffer"; | |
1109 | buffer->buffer_group.attrs = attr; | |
08e7e0ad LPC |
1110 | |
1111 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->buffer_group; | |
1112 | ||
d967cb6b LPC |
1113 | if (buffer->scan_el_attrs != NULL) { |
1114 | attr = buffer->scan_el_attrs->attrs; | |
1115 | while (*attr++ != NULL) | |
1116 | attrcount_orig++; | |
1117 | } | |
1118 | attrcount = attrcount_orig; | |
1119 | INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); | |
1120 | channels = indio_dev->channels; | |
1121 | if (channels) { | |
1122 | /* new magic */ | |
1123 | for (i = 0; i < indio_dev->num_channels; i++) { | |
1124 | if (channels[i].scan_index < 0) | |
1125 | continue; | |
1126 | ||
d967cb6b LPC |
1127 | ret = iio_buffer_add_channel_sysfs(indio_dev, |
1128 | &channels[i]); | |
1129 | if (ret < 0) | |
1130 | goto error_cleanup_dynamic; | |
1131 | attrcount += ret; | |
1132 | if (channels[i].type == IIO_TIMESTAMP) | |
1133 | indio_dev->scan_index_timestamp = | |
1134 | channels[i].scan_index; | |
1135 | } | |
1136 | if (indio_dev->masklength && buffer->scan_mask == NULL) { | |
1137 | buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), | |
1138 | sizeof(*buffer->scan_mask), | |
1139 | GFP_KERNEL); | |
1140 | if (buffer->scan_mask == NULL) { | |
1141 | ret = -ENOMEM; | |
1142 | goto error_cleanup_dynamic; | |
1143 | } | |
1144 | } | |
1145 | } | |
1146 | ||
1147 | buffer->scan_el_group.name = iio_scan_elements_group_name; | |
1148 | ||
1149 | buffer->scan_el_group.attrs = kcalloc(attrcount + 1, | |
1150 | sizeof(buffer->scan_el_group.attrs[0]), | |
1151 | GFP_KERNEL); | |
1152 | if (buffer->scan_el_group.attrs == NULL) { | |
1153 | ret = -ENOMEM; | |
1154 | goto error_free_scan_mask; | |
1155 | } | |
1156 | if (buffer->scan_el_attrs) | |
1157 | memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs, | |
1158 | sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig); | |
1159 | attrn = attrcount_orig; | |
1160 | ||
1161 | list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l) | |
1162 | buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr; | |
1163 | indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group; | |
1164 | ||
1165 | return 0; | |
1166 | ||
1167 | error_free_scan_mask: | |
1168 | kfree(buffer->scan_mask); | |
1169 | error_cleanup_dynamic: | |
1170 | iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); | |
08e7e0ad | 1171 | kfree(indio_dev->buffer->buffer_group.attrs); |
d967cb6b LPC |
1172 | |
1173 | return ret; | |
1174 | } | |
1175 | ||
1176 | void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev) | |
1177 | { | |
1178 | if (!indio_dev->buffer) | |
1179 | return; | |
1180 | ||
1181 | kfree(indio_dev->buffer->scan_mask); | |
08e7e0ad | 1182 | kfree(indio_dev->buffer->buffer_group.attrs); |
d967cb6b LPC |
1183 | kfree(indio_dev->buffer->scan_el_group.attrs); |
1184 | iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list); | |
1185 | } | |
1186 | ||
81636632 LPC |
1187 | /** |
1188 | * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected | |
1189 | * @indio_dev: the iio device | |
1190 | * @mask: scan mask to be checked | |
1191 | * | |
1192 | * Return true if exactly one bit is set in the scan mask, false otherwise. It | |
1193 | * can be used for devices where only one channel can be active for sampling at | |
1194 | * a time. | |
1195 | */ | |
1196 | bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, | |
1197 | const unsigned long *mask) | |
1198 | { | |
1199 | return bitmap_weight(mask, indio_dev->masklength) == 1; | |
1200 | } | |
1201 | EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot); | |
1202 | ||
f79a9098 JC |
1203 | int iio_scan_mask_query(struct iio_dev *indio_dev, |
1204 | struct iio_buffer *buffer, int bit) | |
32b5eeca | 1205 | { |
f8c6f4e9 | 1206 | if (bit > indio_dev->masklength) |
32b5eeca JC |
1207 | return -EINVAL; |
1208 | ||
14555b14 | 1209 | if (!buffer->scan_mask) |
32b5eeca | 1210 | return 0; |
32b5eeca | 1211 | |
2076a20f AB |
1212 | /* Ensure return value is 0 or 1. */ |
1213 | return !!test_bit(bit, buffer->scan_mask); | |
32b5eeca JC |
1214 | }; |
1215 | EXPORT_SYMBOL_GPL(iio_scan_mask_query); | |
5ada4ea9 JC |
1216 | |
1217 | /** | |
0123635a | 1218 | * struct iio_demux_table - table describing demux memcpy ops |
5ada4ea9 | 1219 | * @from: index to copy from |
99698b45 | 1220 | * @to: index to copy to |
5ada4ea9 JC |
1221 | * @length: how many bytes to copy |
1222 | * @l: list head used for management | |
1223 | */ | |
1224 | struct iio_demux_table { | |
1225 | unsigned from; | |
1226 | unsigned to; | |
1227 | unsigned length; | |
1228 | struct list_head l; | |
1229 | }; | |
1230 | ||
5d65d920 LPC |
1231 | static const void *iio_demux(struct iio_buffer *buffer, |
1232 | const void *datain) | |
5ada4ea9 JC |
1233 | { |
1234 | struct iio_demux_table *t; | |
1235 | ||
1236 | if (list_empty(&buffer->demux_list)) | |
1237 | return datain; | |
1238 | list_for_each_entry(t, &buffer->demux_list, l) | |
1239 | memcpy(buffer->demux_bounce + t->to, | |
1240 | datain + t->from, t->length); | |
1241 | ||
1242 | return buffer->demux_bounce; | |
1243 | } | |
1244 | ||
5d65d920 | 1245 | static int iio_push_to_buffer(struct iio_buffer *buffer, const void *data) |
5ada4ea9 | 1246 | { |
5d65d920 | 1247 | const void *dataout = iio_demux(buffer, data); |
37d34556 JC |
1248 | int ret; |
1249 | ||
1250 | ret = buffer->access->store_to(buffer, dataout); | |
1251 | if (ret) | |
1252 | return ret; | |
5ada4ea9 | 1253 | |
37d34556 JC |
1254 | /* |
1255 | * We can't just test for watermark to decide if we wake the poll queue | |
1256 | * because read may request less samples than the watermark. | |
1257 | */ | |
1258 | wake_up_interruptible_poll(&buffer->pollq, POLLIN | POLLRDNORM); | |
1259 | return 0; | |
5ada4ea9 | 1260 | } |
5ada4ea9 | 1261 | |
842cd100 JC |
1262 | static void iio_buffer_demux_free(struct iio_buffer *buffer) |
1263 | { | |
1264 | struct iio_demux_table *p, *q; | |
1265 | list_for_each_entry_safe(p, q, &buffer->demux_list, l) { | |
1266 | list_del(&p->l); | |
1267 | kfree(p); | |
1268 | } | |
1269 | } | |
1270 | ||
84b36ce5 | 1271 | |
5d65d920 | 1272 | int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data) |
84b36ce5 JC |
1273 | { |
1274 | int ret; | |
1275 | struct iio_buffer *buf; | |
1276 | ||
1277 | list_for_each_entry(buf, &indio_dev->buffer_list, buffer_list) { | |
1278 | ret = iio_push_to_buffer(buf, data); | |
1279 | if (ret < 0) | |
1280 | return ret; | |
1281 | } | |
1282 | ||
1283 | return 0; | |
1284 | } | |
1285 | EXPORT_SYMBOL_GPL(iio_push_to_buffers); | |
1286 | ||
cbe88bcc LPC |
1287 | static int iio_buffer_add_demux(struct iio_buffer *buffer, |
1288 | struct iio_demux_table **p, unsigned int in_loc, unsigned int out_loc, | |
1289 | unsigned int length) | |
1290 | { | |
1291 | ||
1292 | if (*p && (*p)->from + (*p)->length == in_loc && | |
1293 | (*p)->to + (*p)->length == out_loc) { | |
1294 | (*p)->length += length; | |
1295 | } else { | |
7cdca178 | 1296 | *p = kmalloc(sizeof(**p), GFP_KERNEL); |
cbe88bcc LPC |
1297 | if (*p == NULL) |
1298 | return -ENOMEM; | |
1299 | (*p)->from = in_loc; | |
1300 | (*p)->to = out_loc; | |
1301 | (*p)->length = length; | |
1302 | list_add_tail(&(*p)->l, &buffer->demux_list); | |
1303 | } | |
1304 | ||
1305 | return 0; | |
1306 | } | |
1307 | ||
84b36ce5 JC |
1308 | static int iio_buffer_update_demux(struct iio_dev *indio_dev, |
1309 | struct iio_buffer *buffer) | |
5ada4ea9 | 1310 | { |
5ada4ea9 JC |
1311 | int ret, in_ind = -1, out_ind, length; |
1312 | unsigned in_loc = 0, out_loc = 0; | |
cbe88bcc | 1313 | struct iio_demux_table *p = NULL; |
5ada4ea9 JC |
1314 | |
1315 | /* Clear out any old demux */ | |
842cd100 | 1316 | iio_buffer_demux_free(buffer); |
5ada4ea9 JC |
1317 | kfree(buffer->demux_bounce); |
1318 | buffer->demux_bounce = NULL; | |
1319 | ||
1320 | /* First work out which scan mode we will actually have */ | |
1321 | if (bitmap_equal(indio_dev->active_scan_mask, | |
1322 | buffer->scan_mask, | |
1323 | indio_dev->masklength)) | |
1324 | return 0; | |
1325 | ||
1326 | /* Now we have the two masks, work from least sig and build up sizes */ | |
1327 | for_each_set_bit(out_ind, | |
61bd55ce | 1328 | buffer->scan_mask, |
5ada4ea9 JC |
1329 | indio_dev->masklength) { |
1330 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
1331 | indio_dev->masklength, | |
1332 | in_ind + 1); | |
1333 | while (in_ind != out_ind) { | |
1334 | in_ind = find_next_bit(indio_dev->active_scan_mask, | |
1335 | indio_dev->masklength, | |
1336 | in_ind + 1); | |
182b4905 | 1337 | length = iio_storage_bytes_for_si(indio_dev, in_ind); |
5ada4ea9 | 1338 | /* Make sure we are aligned */ |
61072dbc | 1339 | in_loc = roundup(in_loc, length) + length; |
5ada4ea9 | 1340 | } |
182b4905 | 1341 | length = iio_storage_bytes_for_si(indio_dev, in_ind); |
61072dbc LPC |
1342 | out_loc = roundup(out_loc, length); |
1343 | in_loc = roundup(in_loc, length); | |
cbe88bcc LPC |
1344 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); |
1345 | if (ret) | |
1346 | goto error_clear_mux_table; | |
5ada4ea9 JC |
1347 | out_loc += length; |
1348 | in_loc += length; | |
1349 | } | |
1350 | /* Relies on scan_timestamp being last */ | |
1351 | if (buffer->scan_timestamp) { | |
182b4905 | 1352 | length = iio_storage_bytes_for_timestamp(indio_dev); |
61072dbc LPC |
1353 | out_loc = roundup(out_loc, length); |
1354 | in_loc = roundup(in_loc, length); | |
cbe88bcc LPC |
1355 | ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); |
1356 | if (ret) | |
1357 | goto error_clear_mux_table; | |
5ada4ea9 JC |
1358 | out_loc += length; |
1359 | in_loc += length; | |
1360 | } | |
1361 | buffer->demux_bounce = kzalloc(out_loc, GFP_KERNEL); | |
1362 | if (buffer->demux_bounce == NULL) { | |
1363 | ret = -ENOMEM; | |
1364 | goto error_clear_mux_table; | |
1365 | } | |
1366 | return 0; | |
1367 | ||
1368 | error_clear_mux_table: | |
842cd100 JC |
1369 | iio_buffer_demux_free(buffer); |
1370 | ||
5ada4ea9 JC |
1371 | return ret; |
1372 | } | |
84b36ce5 JC |
1373 | |
1374 | int iio_update_demux(struct iio_dev *indio_dev) | |
1375 | { | |
1376 | struct iio_buffer *buffer; | |
1377 | int ret; | |
1378 | ||
1379 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { | |
1380 | ret = iio_buffer_update_demux(indio_dev, buffer); | |
1381 | if (ret < 0) | |
1382 | goto error_clear_mux_table; | |
1383 | } | |
1384 | return 0; | |
1385 | ||
1386 | error_clear_mux_table: | |
1387 | list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) | |
1388 | iio_buffer_demux_free(buffer); | |
1389 | ||
1390 | return ret; | |
1391 | } | |
5ada4ea9 | 1392 | EXPORT_SYMBOL_GPL(iio_update_demux); |
9e69c935 LPC |
1393 | |
1394 | /** | |
1395 | * iio_buffer_release() - Free a buffer's resources | |
1396 | * @ref: Pointer to the kref embedded in the iio_buffer struct | |
1397 | * | |
1398 | * This function is called when the last reference to the buffer has been | |
1399 | * dropped. It will typically free all resources allocated by the buffer. Do not | |
1400 | * call this function manually, always use iio_buffer_put() when done using a | |
1401 | * buffer. | |
1402 | */ | |
1403 | static void iio_buffer_release(struct kref *ref) | |
1404 | { | |
1405 | struct iio_buffer *buffer = container_of(ref, struct iio_buffer, ref); | |
1406 | ||
1407 | buffer->access->release(buffer); | |
1408 | } | |
1409 | ||
1410 | /** | |
1411 | * iio_buffer_get() - Grab a reference to the buffer | |
1412 | * @buffer: The buffer to grab a reference for, may be NULL | |
1413 | * | |
1414 | * Returns the pointer to the buffer that was passed into the function. | |
1415 | */ | |
1416 | struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer) | |
1417 | { | |
1418 | if (buffer) | |
1419 | kref_get(&buffer->ref); | |
1420 | ||
1421 | return buffer; | |
1422 | } | |
1423 | EXPORT_SYMBOL_GPL(iio_buffer_get); | |
1424 | ||
1425 | /** | |
1426 | * iio_buffer_put() - Release the reference to the buffer | |
1427 | * @buffer: The buffer to release the reference for, may be NULL | |
1428 | */ | |
1429 | void iio_buffer_put(struct iio_buffer *buffer) | |
1430 | { | |
1431 | if (buffer) | |
1432 | kref_put(&buffer->ref, iio_buffer_release); | |
1433 | } | |
1434 | EXPORT_SYMBOL_GPL(iio_buffer_put); |