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[thirdparty/kernel/stable.git] / drivers / iio / industrialio-core.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* The industrial I/O core
3 *
4 * Copyright (c) 2008 Jonathan Cameron
5 *
6 * Based on elements of hwmon and input subsystems.
7 */
8
9 #define pr_fmt(fmt) "iio-core: " fmt
10
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/idr.h>
14 #include <linux/kdev_t.h>
15 #include <linux/err.h>
16 #include <linux/device.h>
17 #include <linux/fs.h>
18 #include <linux/poll.h>
19 #include <linux/property.h>
20 #include <linux/sched.h>
21 #include <linux/wait.h>
22 #include <linux/cdev.h>
23 #include <linux/slab.h>
24 #include <linux/anon_inodes.h>
25 #include <linux/debugfs.h>
26 #include <linux/mutex.h>
27 #include <linux/iio/iio.h>
28 #include "iio_core.h"
29 #include "iio_core_trigger.h"
30 #include <linux/iio/sysfs.h>
31 #include <linux/iio/events.h>
32 #include <linux/iio/buffer.h>
33 #include <linux/iio/buffer_impl.h>
34
35 /* IDA to assign each registered device a unique id */
36 static DEFINE_IDA(iio_ida);
37
38 static dev_t iio_devt;
39
40 #define IIO_DEV_MAX 256
41 struct bus_type iio_bus_type = {
42 .name = "iio",
43 };
44 EXPORT_SYMBOL(iio_bus_type);
45
46 static struct dentry *iio_debugfs_dentry;
47
48 static const char * const iio_direction[] = {
49 [0] = "in",
50 [1] = "out",
51 };
52
53 static const char * const iio_chan_type_name_spec[] = {
54 [IIO_VOLTAGE] = "voltage",
55 [IIO_CURRENT] = "current",
56 [IIO_POWER] = "power",
57 [IIO_ACCEL] = "accel",
58 [IIO_ANGL_VEL] = "anglvel",
59 [IIO_MAGN] = "magn",
60 [IIO_LIGHT] = "illuminance",
61 [IIO_INTENSITY] = "intensity",
62 [IIO_PROXIMITY] = "proximity",
63 [IIO_TEMP] = "temp",
64 [IIO_INCLI] = "incli",
65 [IIO_ROT] = "rot",
66 [IIO_ANGL] = "angl",
67 [IIO_TIMESTAMP] = "timestamp",
68 [IIO_CAPACITANCE] = "capacitance",
69 [IIO_ALTVOLTAGE] = "altvoltage",
70 [IIO_CCT] = "cct",
71 [IIO_PRESSURE] = "pressure",
72 [IIO_HUMIDITYRELATIVE] = "humidityrelative",
73 [IIO_ACTIVITY] = "activity",
74 [IIO_STEPS] = "steps",
75 [IIO_ENERGY] = "energy",
76 [IIO_DISTANCE] = "distance",
77 [IIO_VELOCITY] = "velocity",
78 [IIO_CONCENTRATION] = "concentration",
79 [IIO_RESISTANCE] = "resistance",
80 [IIO_PH] = "ph",
81 [IIO_UVINDEX] = "uvindex",
82 [IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",
83 [IIO_COUNT] = "count",
84 [IIO_INDEX] = "index",
85 [IIO_GRAVITY] = "gravity",
86 [IIO_POSITIONRELATIVE] = "positionrelative",
87 [IIO_PHASE] = "phase",
88 [IIO_MASSCONCENTRATION] = "massconcentration",
89 };
90
91 static const char * const iio_modifier_names[] = {
92 [IIO_MOD_X] = "x",
93 [IIO_MOD_Y] = "y",
94 [IIO_MOD_Z] = "z",
95 [IIO_MOD_X_AND_Y] = "x&y",
96 [IIO_MOD_X_AND_Z] = "x&z",
97 [IIO_MOD_Y_AND_Z] = "y&z",
98 [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
99 [IIO_MOD_X_OR_Y] = "x|y",
100 [IIO_MOD_X_OR_Z] = "x|z",
101 [IIO_MOD_Y_OR_Z] = "y|z",
102 [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
103 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
104 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
105 [IIO_MOD_LIGHT_BOTH] = "both",
106 [IIO_MOD_LIGHT_IR] = "ir",
107 [IIO_MOD_LIGHT_CLEAR] = "clear",
108 [IIO_MOD_LIGHT_RED] = "red",
109 [IIO_MOD_LIGHT_GREEN] = "green",
110 [IIO_MOD_LIGHT_BLUE] = "blue",
111 [IIO_MOD_LIGHT_UV] = "uv",
112 [IIO_MOD_LIGHT_DUV] = "duv",
113 [IIO_MOD_QUATERNION] = "quaternion",
114 [IIO_MOD_TEMP_AMBIENT] = "ambient",
115 [IIO_MOD_TEMP_OBJECT] = "object",
116 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
117 [IIO_MOD_NORTH_TRUE] = "from_north_true",
118 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
119 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
120 [IIO_MOD_RUNNING] = "running",
121 [IIO_MOD_JOGGING] = "jogging",
122 [IIO_MOD_WALKING] = "walking",
123 [IIO_MOD_STILL] = "still",
124 [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
125 [IIO_MOD_I] = "i",
126 [IIO_MOD_Q] = "q",
127 [IIO_MOD_CO2] = "co2",
128 [IIO_MOD_VOC] = "voc",
129 [IIO_MOD_PM1] = "pm1",
130 [IIO_MOD_PM2P5] = "pm2p5",
131 [IIO_MOD_PM4] = "pm4",
132 [IIO_MOD_PM10] = "pm10",
133 };
134
135 /* relies on pairs of these shared then separate */
136 static const char * const iio_chan_info_postfix[] = {
137 [IIO_CHAN_INFO_RAW] = "raw",
138 [IIO_CHAN_INFO_PROCESSED] = "input",
139 [IIO_CHAN_INFO_SCALE] = "scale",
140 [IIO_CHAN_INFO_OFFSET] = "offset",
141 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
142 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
143 [IIO_CHAN_INFO_PEAK] = "peak_raw",
144 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
145 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
146 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
147 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
148 = "filter_low_pass_3db_frequency",
149 [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
150 = "filter_high_pass_3db_frequency",
151 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
152 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
153 [IIO_CHAN_INFO_PHASE] = "phase",
154 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
155 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
156 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
157 [IIO_CHAN_INFO_ENABLE] = "en",
158 [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
159 [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
160 [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
161 [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
162 [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
163 [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
164 [IIO_CHAN_INFO_THERMOCOUPLE_TYPE] = "thermocouple_type",
165 };
166
167 /**
168 * iio_find_channel_from_si() - get channel from its scan index
169 * @indio_dev: device
170 * @si: scan index to match
171 */
172 const struct iio_chan_spec
173 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
174 {
175 int i;
176
177 for (i = 0; i < indio_dev->num_channels; i++)
178 if (indio_dev->channels[i].scan_index == si)
179 return &indio_dev->channels[i];
180 return NULL;
181 }
182
183 /* This turns up an awful lot */
184 ssize_t iio_read_const_attr(struct device *dev,
185 struct device_attribute *attr,
186 char *buf)
187 {
188 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
189 }
190 EXPORT_SYMBOL(iio_read_const_attr);
191
192 /**
193 * iio_device_set_clock() - Set current timestamping clock for the device
194 * @indio_dev: IIO device structure containing the device
195 * @clock_id: timestamping clock posix identifier to set.
196 */
197 int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id)
198 {
199 int ret;
200 const struct iio_event_interface *ev_int = indio_dev->event_interface;
201
202 ret = mutex_lock_interruptible(&indio_dev->mlock);
203 if (ret)
204 return ret;
205 if ((ev_int && iio_event_enabled(ev_int)) ||
206 iio_buffer_enabled(indio_dev)) {
207 mutex_unlock(&indio_dev->mlock);
208 return -EBUSY;
209 }
210 indio_dev->clock_id = clock_id;
211 mutex_unlock(&indio_dev->mlock);
212
213 return 0;
214 }
215 EXPORT_SYMBOL(iio_device_set_clock);
216
217 /**
218 * iio_get_time_ns() - utility function to get a time stamp for events etc
219 * @indio_dev: device
220 */
221 s64 iio_get_time_ns(const struct iio_dev *indio_dev)
222 {
223 struct timespec64 tp;
224
225 switch (iio_device_get_clock(indio_dev)) {
226 case CLOCK_REALTIME:
227 return ktime_get_real_ns();
228 case CLOCK_MONOTONIC:
229 return ktime_get_ns();
230 case CLOCK_MONOTONIC_RAW:
231 return ktime_get_raw_ns();
232 case CLOCK_REALTIME_COARSE:
233 return ktime_to_ns(ktime_get_coarse_real());
234 case CLOCK_MONOTONIC_COARSE:
235 ktime_get_coarse_ts64(&tp);
236 return timespec64_to_ns(&tp);
237 case CLOCK_BOOTTIME:
238 return ktime_get_boottime_ns();
239 case CLOCK_TAI:
240 return ktime_get_clocktai_ns();
241 default:
242 BUG();
243 }
244 }
245 EXPORT_SYMBOL(iio_get_time_ns);
246
247 /**
248 * iio_get_time_res() - utility function to get time stamp clock resolution in
249 * nano seconds.
250 * @indio_dev: device
251 */
252 unsigned int iio_get_time_res(const struct iio_dev *indio_dev)
253 {
254 switch (iio_device_get_clock(indio_dev)) {
255 case CLOCK_REALTIME:
256 case CLOCK_MONOTONIC:
257 case CLOCK_MONOTONIC_RAW:
258 case CLOCK_BOOTTIME:
259 case CLOCK_TAI:
260 return hrtimer_resolution;
261 case CLOCK_REALTIME_COARSE:
262 case CLOCK_MONOTONIC_COARSE:
263 return LOW_RES_NSEC;
264 default:
265 BUG();
266 }
267 }
268 EXPORT_SYMBOL(iio_get_time_res);
269
270 static int __init iio_init(void)
271 {
272 int ret;
273
274 /* Register sysfs bus */
275 ret = bus_register(&iio_bus_type);
276 if (ret < 0) {
277 pr_err("could not register bus type\n");
278 goto error_nothing;
279 }
280
281 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
282 if (ret < 0) {
283 pr_err("failed to allocate char dev region\n");
284 goto error_unregister_bus_type;
285 }
286
287 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
288
289 return 0;
290
291 error_unregister_bus_type:
292 bus_unregister(&iio_bus_type);
293 error_nothing:
294 return ret;
295 }
296
297 static void __exit iio_exit(void)
298 {
299 if (iio_devt)
300 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
301 bus_unregister(&iio_bus_type);
302 debugfs_remove(iio_debugfs_dentry);
303 }
304
305 #if defined(CONFIG_DEBUG_FS)
306 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
307 size_t count, loff_t *ppos)
308 {
309 struct iio_dev *indio_dev = file->private_data;
310 unsigned val = 0;
311 int ret;
312
313 if (*ppos > 0)
314 return simple_read_from_buffer(userbuf, count, ppos,
315 indio_dev->read_buf,
316 indio_dev->read_buf_len);
317
318 ret = indio_dev->info->debugfs_reg_access(indio_dev,
319 indio_dev->cached_reg_addr,
320 0, &val);
321 if (ret) {
322 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
323 return ret;
324 }
325
326 indio_dev->read_buf_len = snprintf(indio_dev->read_buf,
327 sizeof(indio_dev->read_buf),
328 "0x%X\n", val);
329
330 return simple_read_from_buffer(userbuf, count, ppos,
331 indio_dev->read_buf,
332 indio_dev->read_buf_len);
333 }
334
335 static ssize_t iio_debugfs_write_reg(struct file *file,
336 const char __user *userbuf, size_t count, loff_t *ppos)
337 {
338 struct iio_dev *indio_dev = file->private_data;
339 unsigned reg, val;
340 char buf[80];
341 int ret;
342
343 count = min_t(size_t, count, (sizeof(buf)-1));
344 if (copy_from_user(buf, userbuf, count))
345 return -EFAULT;
346
347 buf[count] = 0;
348
349 ret = sscanf(buf, "%i %i", &reg, &val);
350
351 switch (ret) {
352 case 1:
353 indio_dev->cached_reg_addr = reg;
354 break;
355 case 2:
356 indio_dev->cached_reg_addr = reg;
357 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
358 val, NULL);
359 if (ret) {
360 dev_err(indio_dev->dev.parent, "%s: write failed\n",
361 __func__);
362 return ret;
363 }
364 break;
365 default:
366 return -EINVAL;
367 }
368
369 return count;
370 }
371
372 static const struct file_operations iio_debugfs_reg_fops = {
373 .open = simple_open,
374 .read = iio_debugfs_read_reg,
375 .write = iio_debugfs_write_reg,
376 };
377
378 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
379 {
380 debugfs_remove_recursive(indio_dev->debugfs_dentry);
381 }
382
383 static void iio_device_register_debugfs(struct iio_dev *indio_dev)
384 {
385 if (indio_dev->info->debugfs_reg_access == NULL)
386 return;
387
388 if (!iio_debugfs_dentry)
389 return;
390
391 indio_dev->debugfs_dentry =
392 debugfs_create_dir(dev_name(&indio_dev->dev),
393 iio_debugfs_dentry);
394
395 debugfs_create_file("direct_reg_access", 0644,
396 indio_dev->debugfs_dentry, indio_dev,
397 &iio_debugfs_reg_fops);
398 }
399 #else
400 static void iio_device_register_debugfs(struct iio_dev *indio_dev)
401 {
402 }
403
404 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
405 {
406 }
407 #endif /* CONFIG_DEBUG_FS */
408
409 static ssize_t iio_read_channel_ext_info(struct device *dev,
410 struct device_attribute *attr,
411 char *buf)
412 {
413 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
414 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
415 const struct iio_chan_spec_ext_info *ext_info;
416
417 ext_info = &this_attr->c->ext_info[this_attr->address];
418
419 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
420 }
421
422 static ssize_t iio_write_channel_ext_info(struct device *dev,
423 struct device_attribute *attr,
424 const char *buf,
425 size_t len)
426 {
427 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
428 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
429 const struct iio_chan_spec_ext_info *ext_info;
430
431 ext_info = &this_attr->c->ext_info[this_attr->address];
432
433 return ext_info->write(indio_dev, ext_info->private,
434 this_attr->c, buf, len);
435 }
436
437 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
438 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
439 {
440 const struct iio_enum *e = (const struct iio_enum *)priv;
441 unsigned int i;
442 size_t len = 0;
443
444 if (!e->num_items)
445 return 0;
446
447 for (i = 0; i < e->num_items; ++i)
448 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
449
450 /* replace last space with a newline */
451 buf[len - 1] = '\n';
452
453 return len;
454 }
455 EXPORT_SYMBOL_GPL(iio_enum_available_read);
456
457 ssize_t iio_enum_read(struct iio_dev *indio_dev,
458 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
459 {
460 const struct iio_enum *e = (const struct iio_enum *)priv;
461 int i;
462
463 if (!e->get)
464 return -EINVAL;
465
466 i = e->get(indio_dev, chan);
467 if (i < 0)
468 return i;
469 else if (i >= e->num_items)
470 return -EINVAL;
471
472 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
473 }
474 EXPORT_SYMBOL_GPL(iio_enum_read);
475
476 ssize_t iio_enum_write(struct iio_dev *indio_dev,
477 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
478 size_t len)
479 {
480 const struct iio_enum *e = (const struct iio_enum *)priv;
481 int ret;
482
483 if (!e->set)
484 return -EINVAL;
485
486 ret = __sysfs_match_string(e->items, e->num_items, buf);
487 if (ret < 0)
488 return ret;
489
490 ret = e->set(indio_dev, chan, ret);
491 return ret ? ret : len;
492 }
493 EXPORT_SYMBOL_GPL(iio_enum_write);
494
495 static const struct iio_mount_matrix iio_mount_idmatrix = {
496 .rotation = {
497 "1", "0", "0",
498 "0", "1", "0",
499 "0", "0", "1"
500 }
501 };
502
503 static int iio_setup_mount_idmatrix(const struct device *dev,
504 struct iio_mount_matrix *matrix)
505 {
506 *matrix = iio_mount_idmatrix;
507 dev_info(dev, "mounting matrix not found: using identity...\n");
508 return 0;
509 }
510
511 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
512 const struct iio_chan_spec *chan, char *buf)
513 {
514 const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
515 priv)(indio_dev, chan);
516
517 if (IS_ERR(mtx))
518 return PTR_ERR(mtx);
519
520 if (!mtx)
521 mtx = &iio_mount_idmatrix;
522
523 return snprintf(buf, PAGE_SIZE, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
524 mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
525 mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
526 mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
527 }
528 EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
529
530 /**
531 * iio_read_mount_matrix() - retrieve iio device mounting matrix from
532 * device "mount-matrix" property
533 * @dev: device the mounting matrix property is assigned to
534 * @propname: device specific mounting matrix property name
535 * @matrix: where to store retrieved matrix
536 *
537 * If device is assigned no mounting matrix property, a default 3x3 identity
538 * matrix will be filled in.
539 *
540 * Return: 0 if success, or a negative error code on failure.
541 */
542 int iio_read_mount_matrix(struct device *dev, const char *propname,
543 struct iio_mount_matrix *matrix)
544 {
545 size_t len = ARRAY_SIZE(iio_mount_idmatrix.rotation);
546 int err;
547
548 err = device_property_read_string_array(dev, propname,
549 matrix->rotation, len);
550 if (err == len)
551 return 0;
552
553 if (err >= 0)
554 /* Invalid number of matrix entries. */
555 return -EINVAL;
556
557 if (err != -EINVAL)
558 /* Invalid matrix declaration format. */
559 return err;
560
561 /* Matrix was not declared at all: fallback to identity. */
562 return iio_setup_mount_idmatrix(dev, matrix);
563 }
564 EXPORT_SYMBOL(iio_read_mount_matrix);
565
566 static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
567 int size, const int *vals)
568 {
569 unsigned long long tmp;
570 int tmp0, tmp1;
571 bool scale_db = false;
572
573 switch (type) {
574 case IIO_VAL_INT:
575 return scnprintf(buf, len, "%d", vals[0]);
576 case IIO_VAL_INT_PLUS_MICRO_DB:
577 scale_db = true;
578 /* fall through */
579 case IIO_VAL_INT_PLUS_MICRO:
580 if (vals[1] < 0)
581 return scnprintf(buf, len, "-%d.%06u%s", abs(vals[0]),
582 -vals[1], scale_db ? " dB" : "");
583 else
584 return scnprintf(buf, len, "%d.%06u%s", vals[0], vals[1],
585 scale_db ? " dB" : "");
586 case IIO_VAL_INT_PLUS_NANO:
587 if (vals[1] < 0)
588 return scnprintf(buf, len, "-%d.%09u", abs(vals[0]),
589 -vals[1]);
590 else
591 return scnprintf(buf, len, "%d.%09u", vals[0], vals[1]);
592 case IIO_VAL_FRACTIONAL:
593 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
594 tmp1 = vals[1];
595 tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
596 return scnprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
597 case IIO_VAL_FRACTIONAL_LOG2:
598 tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
599 tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
600 return scnprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
601 case IIO_VAL_INT_MULTIPLE:
602 {
603 int i;
604 int l = 0;
605
606 for (i = 0; i < size; ++i) {
607 l += scnprintf(&buf[l], len - l, "%d ", vals[i]);
608 if (l >= len)
609 break;
610 }
611 return l;
612 }
613 case IIO_VAL_CHAR:
614 return scnprintf(buf, len, "%c", (char)vals[0]);
615 default:
616 return 0;
617 }
618 }
619
620 /**
621 * iio_format_value() - Formats a IIO value into its string representation
622 * @buf: The buffer to which the formatted value gets written
623 * which is assumed to be big enough (i.e. PAGE_SIZE).
624 * @type: One of the IIO_VAL_* constants. This decides how the val
625 * and val2 parameters are formatted.
626 * @size: Number of IIO value entries contained in vals
627 * @vals: Pointer to the values, exact meaning depends on the
628 * type parameter.
629 *
630 * Return: 0 by default, a negative number on failure or the
631 * total number of characters written for a type that belongs
632 * to the IIO_VAL_* constant.
633 */
634 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
635 {
636 ssize_t len;
637
638 len = __iio_format_value(buf, PAGE_SIZE, type, size, vals);
639 if (len >= PAGE_SIZE - 1)
640 return -EFBIG;
641
642 return len + sprintf(buf + len, "\n");
643 }
644 EXPORT_SYMBOL_GPL(iio_format_value);
645
646 static ssize_t iio_read_channel_info(struct device *dev,
647 struct device_attribute *attr,
648 char *buf)
649 {
650 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
651 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
652 int vals[INDIO_MAX_RAW_ELEMENTS];
653 int ret;
654 int val_len = 2;
655
656 if (indio_dev->info->read_raw_multi)
657 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
658 INDIO_MAX_RAW_ELEMENTS,
659 vals, &val_len,
660 this_attr->address);
661 else
662 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
663 &vals[0], &vals[1], this_attr->address);
664
665 if (ret < 0)
666 return ret;
667
668 return iio_format_value(buf, ret, val_len, vals);
669 }
670
671 static ssize_t iio_format_avail_list(char *buf, const int *vals,
672 int type, int length)
673 {
674 int i;
675 ssize_t len = 0;
676
677 switch (type) {
678 case IIO_VAL_INT:
679 for (i = 0; i < length; i++) {
680 len += __iio_format_value(buf + len, PAGE_SIZE - len,
681 type, 1, &vals[i]);
682 if (len >= PAGE_SIZE)
683 return -EFBIG;
684 if (i < length - 1)
685 len += scnprintf(buf + len, PAGE_SIZE - len,
686 " ");
687 else
688 len += scnprintf(buf + len, PAGE_SIZE - len,
689 "\n");
690 if (len >= PAGE_SIZE)
691 return -EFBIG;
692 }
693 break;
694 default:
695 for (i = 0; i < length / 2; i++) {
696 len += __iio_format_value(buf + len, PAGE_SIZE - len,
697 type, 2, &vals[i * 2]);
698 if (len >= PAGE_SIZE)
699 return -EFBIG;
700 if (i < length / 2 - 1)
701 len += scnprintf(buf + len, PAGE_SIZE - len,
702 " ");
703 else
704 len += scnprintf(buf + len, PAGE_SIZE - len,
705 "\n");
706 if (len >= PAGE_SIZE)
707 return -EFBIG;
708 }
709 }
710
711 return len;
712 }
713
714 static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
715 {
716 int i;
717 ssize_t len;
718
719 len = snprintf(buf, PAGE_SIZE, "[");
720 switch (type) {
721 case IIO_VAL_INT:
722 for (i = 0; i < 3; i++) {
723 len += __iio_format_value(buf + len, PAGE_SIZE - len,
724 type, 1, &vals[i]);
725 if (len >= PAGE_SIZE)
726 return -EFBIG;
727 if (i < 2)
728 len += scnprintf(buf + len, PAGE_SIZE - len,
729 " ");
730 else
731 len += scnprintf(buf + len, PAGE_SIZE - len,
732 "]\n");
733 if (len >= PAGE_SIZE)
734 return -EFBIG;
735 }
736 break;
737 default:
738 for (i = 0; i < 3; i++) {
739 len += __iio_format_value(buf + len, PAGE_SIZE - len,
740 type, 2, &vals[i * 2]);
741 if (len >= PAGE_SIZE)
742 return -EFBIG;
743 if (i < 2)
744 len += scnprintf(buf + len, PAGE_SIZE - len,
745 " ");
746 else
747 len += scnprintf(buf + len, PAGE_SIZE - len,
748 "]\n");
749 if (len >= PAGE_SIZE)
750 return -EFBIG;
751 }
752 }
753
754 return len;
755 }
756
757 static ssize_t iio_read_channel_info_avail(struct device *dev,
758 struct device_attribute *attr,
759 char *buf)
760 {
761 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
762 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
763 const int *vals;
764 int ret;
765 int length;
766 int type;
767
768 ret = indio_dev->info->read_avail(indio_dev, this_attr->c,
769 &vals, &type, &length,
770 this_attr->address);
771
772 if (ret < 0)
773 return ret;
774 switch (ret) {
775 case IIO_AVAIL_LIST:
776 return iio_format_avail_list(buf, vals, type, length);
777 case IIO_AVAIL_RANGE:
778 return iio_format_avail_range(buf, vals, type);
779 default:
780 return -EINVAL;
781 }
782 }
783
784 /**
785 * __iio_str_to_fixpoint() - Parse a fixed-point number from a string
786 * @str: The string to parse
787 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
788 * @integer: The integer part of the number
789 * @fract: The fractional part of the number
790 * @scale_db: True if this should parse as dB
791 *
792 * Returns 0 on success, or a negative error code if the string could not be
793 * parsed.
794 */
795 static int __iio_str_to_fixpoint(const char *str, int fract_mult,
796 int *integer, int *fract, bool scale_db)
797 {
798 int i = 0, f = 0;
799 bool integer_part = true, negative = false;
800
801 if (fract_mult == 0) {
802 *fract = 0;
803
804 return kstrtoint(str, 0, integer);
805 }
806
807 if (str[0] == '-') {
808 negative = true;
809 str++;
810 } else if (str[0] == '+') {
811 str++;
812 }
813
814 while (*str) {
815 if ('0' <= *str && *str <= '9') {
816 if (integer_part) {
817 i = i * 10 + *str - '0';
818 } else {
819 f += fract_mult * (*str - '0');
820 fract_mult /= 10;
821 }
822 } else if (*str == '\n') {
823 if (*(str + 1) == '\0')
824 break;
825 else
826 return -EINVAL;
827 } else if (!strncmp(str, " dB", sizeof(" dB") - 1) && scale_db) {
828 /* Ignore the dB suffix */
829 str += sizeof(" dB") - 1;
830 continue;
831 } else if (!strncmp(str, "dB", sizeof("dB") - 1) && scale_db) {
832 /* Ignore the dB suffix */
833 str += sizeof("dB") - 1;
834 continue;
835 } else if (*str == '.' && integer_part) {
836 integer_part = false;
837 } else {
838 return -EINVAL;
839 }
840 str++;
841 }
842
843 if (negative) {
844 if (i)
845 i = -i;
846 else
847 f = -f;
848 }
849
850 *integer = i;
851 *fract = f;
852
853 return 0;
854 }
855
856 /**
857 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
858 * @str: The string to parse
859 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
860 * @integer: The integer part of the number
861 * @fract: The fractional part of the number
862 *
863 * Returns 0 on success, or a negative error code if the string could not be
864 * parsed.
865 */
866 int iio_str_to_fixpoint(const char *str, int fract_mult,
867 int *integer, int *fract)
868 {
869 return __iio_str_to_fixpoint(str, fract_mult, integer, fract, false);
870 }
871 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
872
873 static ssize_t iio_write_channel_info(struct device *dev,
874 struct device_attribute *attr,
875 const char *buf,
876 size_t len)
877 {
878 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
879 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
880 int ret, fract_mult = 100000;
881 int integer, fract = 0;
882 bool is_char = false;
883 bool scale_db = false;
884
885 /* Assumes decimal - precision based on number of digits */
886 if (!indio_dev->info->write_raw)
887 return -EINVAL;
888
889 if (indio_dev->info->write_raw_get_fmt)
890 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
891 this_attr->c, this_attr->address)) {
892 case IIO_VAL_INT:
893 fract_mult = 0;
894 break;
895 case IIO_VAL_INT_PLUS_MICRO_DB:
896 scale_db = true;
897 /* fall through */
898 case IIO_VAL_INT_PLUS_MICRO:
899 fract_mult = 100000;
900 break;
901 case IIO_VAL_INT_PLUS_NANO:
902 fract_mult = 100000000;
903 break;
904 case IIO_VAL_CHAR:
905 is_char = true;
906 break;
907 default:
908 return -EINVAL;
909 }
910
911 if (is_char) {
912 char ch;
913
914 if (sscanf(buf, "%c", &ch) != 1)
915 return -EINVAL;
916 integer = ch;
917 } else {
918 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
919 if (ret)
920 return ret;
921 }
922 ret = __iio_str_to_fixpoint(buf, fract_mult, &integer, &fract,
923 scale_db);
924 if (ret)
925 return ret;
926
927 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
928 integer, fract, this_attr->address);
929 if (ret)
930 return ret;
931
932 return len;
933 }
934
935 static
936 int __iio_device_attr_init(struct device_attribute *dev_attr,
937 const char *postfix,
938 struct iio_chan_spec const *chan,
939 ssize_t (*readfunc)(struct device *dev,
940 struct device_attribute *attr,
941 char *buf),
942 ssize_t (*writefunc)(struct device *dev,
943 struct device_attribute *attr,
944 const char *buf,
945 size_t len),
946 enum iio_shared_by shared_by)
947 {
948 int ret = 0;
949 char *name = NULL;
950 char *full_postfix;
951 sysfs_attr_init(&dev_attr->attr);
952
953 /* Build up postfix of <extend_name>_<modifier>_postfix */
954 if (chan->modified && (shared_by == IIO_SEPARATE)) {
955 if (chan->extend_name)
956 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
957 iio_modifier_names[chan
958 ->channel2],
959 chan->extend_name,
960 postfix);
961 else
962 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
963 iio_modifier_names[chan
964 ->channel2],
965 postfix);
966 } else {
967 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
968 full_postfix = kstrdup(postfix, GFP_KERNEL);
969 else
970 full_postfix = kasprintf(GFP_KERNEL,
971 "%s_%s",
972 chan->extend_name,
973 postfix);
974 }
975 if (full_postfix == NULL)
976 return -ENOMEM;
977
978 if (chan->differential) { /* Differential can not have modifier */
979 switch (shared_by) {
980 case IIO_SHARED_BY_ALL:
981 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
982 break;
983 case IIO_SHARED_BY_DIR:
984 name = kasprintf(GFP_KERNEL, "%s_%s",
985 iio_direction[chan->output],
986 full_postfix);
987 break;
988 case IIO_SHARED_BY_TYPE:
989 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
990 iio_direction[chan->output],
991 iio_chan_type_name_spec[chan->type],
992 iio_chan_type_name_spec[chan->type],
993 full_postfix);
994 break;
995 case IIO_SEPARATE:
996 if (!chan->indexed) {
997 WARN(1, "Differential channels must be indexed\n");
998 ret = -EINVAL;
999 goto error_free_full_postfix;
1000 }
1001 name = kasprintf(GFP_KERNEL,
1002 "%s_%s%d-%s%d_%s",
1003 iio_direction[chan->output],
1004 iio_chan_type_name_spec[chan->type],
1005 chan->channel,
1006 iio_chan_type_name_spec[chan->type],
1007 chan->channel2,
1008 full_postfix);
1009 break;
1010 }
1011 } else { /* Single ended */
1012 switch (shared_by) {
1013 case IIO_SHARED_BY_ALL:
1014 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
1015 break;
1016 case IIO_SHARED_BY_DIR:
1017 name = kasprintf(GFP_KERNEL, "%s_%s",
1018 iio_direction[chan->output],
1019 full_postfix);
1020 break;
1021 case IIO_SHARED_BY_TYPE:
1022 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
1023 iio_direction[chan->output],
1024 iio_chan_type_name_spec[chan->type],
1025 full_postfix);
1026 break;
1027
1028 case IIO_SEPARATE:
1029 if (chan->indexed)
1030 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
1031 iio_direction[chan->output],
1032 iio_chan_type_name_spec[chan->type],
1033 chan->channel,
1034 full_postfix);
1035 else
1036 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
1037 iio_direction[chan->output],
1038 iio_chan_type_name_spec[chan->type],
1039 full_postfix);
1040 break;
1041 }
1042 }
1043 if (name == NULL) {
1044 ret = -ENOMEM;
1045 goto error_free_full_postfix;
1046 }
1047 dev_attr->attr.name = name;
1048
1049 if (readfunc) {
1050 dev_attr->attr.mode |= S_IRUGO;
1051 dev_attr->show = readfunc;
1052 }
1053
1054 if (writefunc) {
1055 dev_attr->attr.mode |= S_IWUSR;
1056 dev_attr->store = writefunc;
1057 }
1058
1059 error_free_full_postfix:
1060 kfree(full_postfix);
1061
1062 return ret;
1063 }
1064
1065 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
1066 {
1067 kfree(dev_attr->attr.name);
1068 }
1069
1070 int __iio_add_chan_devattr(const char *postfix,
1071 struct iio_chan_spec const *chan,
1072 ssize_t (*readfunc)(struct device *dev,
1073 struct device_attribute *attr,
1074 char *buf),
1075 ssize_t (*writefunc)(struct device *dev,
1076 struct device_attribute *attr,
1077 const char *buf,
1078 size_t len),
1079 u64 mask,
1080 enum iio_shared_by shared_by,
1081 struct device *dev,
1082 struct list_head *attr_list)
1083 {
1084 int ret;
1085 struct iio_dev_attr *iio_attr, *t;
1086
1087 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
1088 if (iio_attr == NULL)
1089 return -ENOMEM;
1090 ret = __iio_device_attr_init(&iio_attr->dev_attr,
1091 postfix, chan,
1092 readfunc, writefunc, shared_by);
1093 if (ret)
1094 goto error_iio_dev_attr_free;
1095 iio_attr->c = chan;
1096 iio_attr->address = mask;
1097 list_for_each_entry(t, attr_list, l)
1098 if (strcmp(t->dev_attr.attr.name,
1099 iio_attr->dev_attr.attr.name) == 0) {
1100 if (shared_by == IIO_SEPARATE)
1101 dev_err(dev, "tried to double register : %s\n",
1102 t->dev_attr.attr.name);
1103 ret = -EBUSY;
1104 goto error_device_attr_deinit;
1105 }
1106 list_add(&iio_attr->l, attr_list);
1107
1108 return 0;
1109
1110 error_device_attr_deinit:
1111 __iio_device_attr_deinit(&iio_attr->dev_attr);
1112 error_iio_dev_attr_free:
1113 kfree(iio_attr);
1114 return ret;
1115 }
1116
1117 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
1118 struct iio_chan_spec const *chan,
1119 enum iio_shared_by shared_by,
1120 const long *infomask)
1121 {
1122 int i, ret, attrcount = 0;
1123
1124 for_each_set_bit(i, infomask, sizeof(*infomask)*8) {
1125 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1126 return -EINVAL;
1127 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
1128 chan,
1129 &iio_read_channel_info,
1130 &iio_write_channel_info,
1131 i,
1132 shared_by,
1133 &indio_dev->dev,
1134 &indio_dev->channel_attr_list);
1135 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1136 continue;
1137 else if (ret < 0)
1138 return ret;
1139 attrcount++;
1140 }
1141
1142 return attrcount;
1143 }
1144
1145 static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
1146 struct iio_chan_spec const *chan,
1147 enum iio_shared_by shared_by,
1148 const long *infomask)
1149 {
1150 int i, ret, attrcount = 0;
1151 char *avail_postfix;
1152
1153 for_each_set_bit(i, infomask, sizeof(*infomask) * 8) {
1154 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1155 return -EINVAL;
1156 avail_postfix = kasprintf(GFP_KERNEL,
1157 "%s_available",
1158 iio_chan_info_postfix[i]);
1159 if (!avail_postfix)
1160 return -ENOMEM;
1161
1162 ret = __iio_add_chan_devattr(avail_postfix,
1163 chan,
1164 &iio_read_channel_info_avail,
1165 NULL,
1166 i,
1167 shared_by,
1168 &indio_dev->dev,
1169 &indio_dev->channel_attr_list);
1170 kfree(avail_postfix);
1171 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1172 continue;
1173 else if (ret < 0)
1174 return ret;
1175 attrcount++;
1176 }
1177
1178 return attrcount;
1179 }
1180
1181 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
1182 struct iio_chan_spec const *chan)
1183 {
1184 int ret, attrcount = 0;
1185 const struct iio_chan_spec_ext_info *ext_info;
1186
1187 if (chan->channel < 0)
1188 return 0;
1189 ret = iio_device_add_info_mask_type(indio_dev, chan,
1190 IIO_SEPARATE,
1191 &chan->info_mask_separate);
1192 if (ret < 0)
1193 return ret;
1194 attrcount += ret;
1195
1196 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1197 IIO_SEPARATE,
1198 &chan->
1199 info_mask_separate_available);
1200 if (ret < 0)
1201 return ret;
1202 attrcount += ret;
1203
1204 ret = iio_device_add_info_mask_type(indio_dev, chan,
1205 IIO_SHARED_BY_TYPE,
1206 &chan->info_mask_shared_by_type);
1207 if (ret < 0)
1208 return ret;
1209 attrcount += ret;
1210
1211 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1212 IIO_SHARED_BY_TYPE,
1213 &chan->
1214 info_mask_shared_by_type_available);
1215 if (ret < 0)
1216 return ret;
1217 attrcount += ret;
1218
1219 ret = iio_device_add_info_mask_type(indio_dev, chan,
1220 IIO_SHARED_BY_DIR,
1221 &chan->info_mask_shared_by_dir);
1222 if (ret < 0)
1223 return ret;
1224 attrcount += ret;
1225
1226 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1227 IIO_SHARED_BY_DIR,
1228 &chan->info_mask_shared_by_dir_available);
1229 if (ret < 0)
1230 return ret;
1231 attrcount += ret;
1232
1233 ret = iio_device_add_info_mask_type(indio_dev, chan,
1234 IIO_SHARED_BY_ALL,
1235 &chan->info_mask_shared_by_all);
1236 if (ret < 0)
1237 return ret;
1238 attrcount += ret;
1239
1240 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1241 IIO_SHARED_BY_ALL,
1242 &chan->info_mask_shared_by_all_available);
1243 if (ret < 0)
1244 return ret;
1245 attrcount += ret;
1246
1247 if (chan->ext_info) {
1248 unsigned int i = 0;
1249 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
1250 ret = __iio_add_chan_devattr(ext_info->name,
1251 chan,
1252 ext_info->read ?
1253 &iio_read_channel_ext_info : NULL,
1254 ext_info->write ?
1255 &iio_write_channel_ext_info : NULL,
1256 i,
1257 ext_info->shared,
1258 &indio_dev->dev,
1259 &indio_dev->channel_attr_list);
1260 i++;
1261 if (ret == -EBUSY && ext_info->shared)
1262 continue;
1263
1264 if (ret)
1265 return ret;
1266
1267 attrcount++;
1268 }
1269 }
1270
1271 return attrcount;
1272 }
1273
1274 /**
1275 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
1276 * @attr_list: List of IIO device attributes
1277 *
1278 * This function frees the memory allocated for each of the IIO device
1279 * attributes in the list.
1280 */
1281 void iio_free_chan_devattr_list(struct list_head *attr_list)
1282 {
1283 struct iio_dev_attr *p, *n;
1284
1285 list_for_each_entry_safe(p, n, attr_list, l) {
1286 kfree(p->dev_attr.attr.name);
1287 list_del(&p->l);
1288 kfree(p);
1289 }
1290 }
1291
1292 static ssize_t iio_show_dev_name(struct device *dev,
1293 struct device_attribute *attr,
1294 char *buf)
1295 {
1296 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1297 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
1298 }
1299
1300 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
1301
1302 static ssize_t iio_show_dev_label(struct device *dev,
1303 struct device_attribute *attr,
1304 char *buf)
1305 {
1306 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1307 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->label);
1308 }
1309
1310 static DEVICE_ATTR(label, S_IRUGO, iio_show_dev_label, NULL);
1311
1312 static ssize_t iio_show_timestamp_clock(struct device *dev,
1313 struct device_attribute *attr,
1314 char *buf)
1315 {
1316 const struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1317 const clockid_t clk = iio_device_get_clock(indio_dev);
1318 const char *name;
1319 ssize_t sz;
1320
1321 switch (clk) {
1322 case CLOCK_REALTIME:
1323 name = "realtime\n";
1324 sz = sizeof("realtime\n");
1325 break;
1326 case CLOCK_MONOTONIC:
1327 name = "monotonic\n";
1328 sz = sizeof("monotonic\n");
1329 break;
1330 case CLOCK_MONOTONIC_RAW:
1331 name = "monotonic_raw\n";
1332 sz = sizeof("monotonic_raw\n");
1333 break;
1334 case CLOCK_REALTIME_COARSE:
1335 name = "realtime_coarse\n";
1336 sz = sizeof("realtime_coarse\n");
1337 break;
1338 case CLOCK_MONOTONIC_COARSE:
1339 name = "monotonic_coarse\n";
1340 sz = sizeof("monotonic_coarse\n");
1341 break;
1342 case CLOCK_BOOTTIME:
1343 name = "boottime\n";
1344 sz = sizeof("boottime\n");
1345 break;
1346 case CLOCK_TAI:
1347 name = "tai\n";
1348 sz = sizeof("tai\n");
1349 break;
1350 default:
1351 BUG();
1352 }
1353
1354 memcpy(buf, name, sz);
1355 return sz;
1356 }
1357
1358 static ssize_t iio_store_timestamp_clock(struct device *dev,
1359 struct device_attribute *attr,
1360 const char *buf, size_t len)
1361 {
1362 clockid_t clk;
1363 int ret;
1364
1365 if (sysfs_streq(buf, "realtime"))
1366 clk = CLOCK_REALTIME;
1367 else if (sysfs_streq(buf, "monotonic"))
1368 clk = CLOCK_MONOTONIC;
1369 else if (sysfs_streq(buf, "monotonic_raw"))
1370 clk = CLOCK_MONOTONIC_RAW;
1371 else if (sysfs_streq(buf, "realtime_coarse"))
1372 clk = CLOCK_REALTIME_COARSE;
1373 else if (sysfs_streq(buf, "monotonic_coarse"))
1374 clk = CLOCK_MONOTONIC_COARSE;
1375 else if (sysfs_streq(buf, "boottime"))
1376 clk = CLOCK_BOOTTIME;
1377 else if (sysfs_streq(buf, "tai"))
1378 clk = CLOCK_TAI;
1379 else
1380 return -EINVAL;
1381
1382 ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);
1383 if (ret)
1384 return ret;
1385
1386 return len;
1387 }
1388
1389 static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
1390 iio_show_timestamp_clock, iio_store_timestamp_clock);
1391
1392 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
1393 {
1394 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
1395 struct iio_dev_attr *p;
1396 struct attribute **attr, *clk = NULL;
1397
1398 /* First count elements in any existing group */
1399 if (indio_dev->info->attrs) {
1400 attr = indio_dev->info->attrs->attrs;
1401 while (*attr++ != NULL)
1402 attrcount_orig++;
1403 }
1404 attrcount = attrcount_orig;
1405 /*
1406 * New channel registration method - relies on the fact a group does
1407 * not need to be initialized if its name is NULL.
1408 */
1409 if (indio_dev->channels)
1410 for (i = 0; i < indio_dev->num_channels; i++) {
1411 const struct iio_chan_spec *chan =
1412 &indio_dev->channels[i];
1413
1414 if (chan->type == IIO_TIMESTAMP)
1415 clk = &dev_attr_current_timestamp_clock.attr;
1416
1417 ret = iio_device_add_channel_sysfs(indio_dev, chan);
1418 if (ret < 0)
1419 goto error_clear_attrs;
1420 attrcount += ret;
1421 }
1422
1423 if (indio_dev->event_interface)
1424 clk = &dev_attr_current_timestamp_clock.attr;
1425
1426 if (indio_dev->name)
1427 attrcount++;
1428 if (indio_dev->label)
1429 attrcount++;
1430 if (clk)
1431 attrcount++;
1432
1433 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
1434 sizeof(indio_dev->chan_attr_group.attrs[0]),
1435 GFP_KERNEL);
1436 if (indio_dev->chan_attr_group.attrs == NULL) {
1437 ret = -ENOMEM;
1438 goto error_clear_attrs;
1439 }
1440 /* Copy across original attributes */
1441 if (indio_dev->info->attrs)
1442 memcpy(indio_dev->chan_attr_group.attrs,
1443 indio_dev->info->attrs->attrs,
1444 sizeof(indio_dev->chan_attr_group.attrs[0])
1445 *attrcount_orig);
1446 attrn = attrcount_orig;
1447 /* Add all elements from the list. */
1448 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
1449 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
1450 if (indio_dev->name)
1451 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
1452 if (indio_dev->label)
1453 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_label.attr;
1454 if (clk)
1455 indio_dev->chan_attr_group.attrs[attrn++] = clk;
1456
1457 indio_dev->groups[indio_dev->groupcounter++] =
1458 &indio_dev->chan_attr_group;
1459
1460 return 0;
1461
1462 error_clear_attrs:
1463 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1464
1465 return ret;
1466 }
1467
1468 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
1469 {
1470
1471 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1472 kfree(indio_dev->chan_attr_group.attrs);
1473 indio_dev->chan_attr_group.attrs = NULL;
1474 }
1475
1476 static void iio_dev_release(struct device *device)
1477 {
1478 struct iio_dev *indio_dev = dev_to_iio_dev(device);
1479 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1480 iio_device_unregister_trigger_consumer(indio_dev);
1481 iio_device_unregister_eventset(indio_dev);
1482 iio_device_unregister_sysfs(indio_dev);
1483
1484 iio_buffer_put(indio_dev->buffer);
1485
1486 ida_simple_remove(&iio_ida, indio_dev->id);
1487 kfree(indio_dev);
1488 }
1489
1490 struct device_type iio_device_type = {
1491 .name = "iio_device",
1492 .release = iio_dev_release,
1493 };
1494
1495 /**
1496 * iio_device_alloc() - allocate an iio_dev from a driver
1497 * @sizeof_priv: Space to allocate for private structure.
1498 **/
1499 struct iio_dev *iio_device_alloc(int sizeof_priv)
1500 {
1501 struct iio_dev *dev;
1502 size_t alloc_size;
1503
1504 alloc_size = sizeof(struct iio_dev);
1505 if (sizeof_priv) {
1506 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1507 alloc_size += sizeof_priv;
1508 }
1509 /* ensure 32-byte alignment of whole construct ? */
1510 alloc_size += IIO_ALIGN - 1;
1511
1512 dev = kzalloc(alloc_size, GFP_KERNEL);
1513
1514 if (dev) {
1515 dev->dev.groups = dev->groups;
1516 dev->dev.type = &iio_device_type;
1517 dev->dev.bus = &iio_bus_type;
1518 device_initialize(&dev->dev);
1519 dev_set_drvdata(&dev->dev, (void *)dev);
1520 mutex_init(&dev->mlock);
1521 mutex_init(&dev->info_exist_lock);
1522 INIT_LIST_HEAD(&dev->channel_attr_list);
1523
1524 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1525 if (dev->id < 0) {
1526 /* cannot use a dev_err as the name isn't available */
1527 pr_err("failed to get device id\n");
1528 kfree(dev);
1529 return NULL;
1530 }
1531 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1532 INIT_LIST_HEAD(&dev->buffer_list);
1533 }
1534
1535 return dev;
1536 }
1537 EXPORT_SYMBOL(iio_device_alloc);
1538
1539 /**
1540 * iio_device_free() - free an iio_dev from a driver
1541 * @dev: the iio_dev associated with the device
1542 **/
1543 void iio_device_free(struct iio_dev *dev)
1544 {
1545 if (dev)
1546 put_device(&dev->dev);
1547 }
1548 EXPORT_SYMBOL(iio_device_free);
1549
1550 static void devm_iio_device_release(struct device *dev, void *res)
1551 {
1552 iio_device_free(*(struct iio_dev **)res);
1553 }
1554
1555 /**
1556 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1557 * @dev: Device to allocate iio_dev for
1558 * @sizeof_priv: Space to allocate for private structure.
1559 *
1560 * Managed iio_device_alloc. iio_dev allocated with this function is
1561 * automatically freed on driver detach.
1562 *
1563 * RETURNS:
1564 * Pointer to allocated iio_dev on success, NULL on failure.
1565 */
1566 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1567 {
1568 struct iio_dev **ptr, *iio_dev;
1569
1570 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1571 GFP_KERNEL);
1572 if (!ptr)
1573 return NULL;
1574
1575 iio_dev = iio_device_alloc(sizeof_priv);
1576 if (iio_dev) {
1577 *ptr = iio_dev;
1578 devres_add(dev, ptr);
1579 } else {
1580 devres_free(ptr);
1581 }
1582
1583 return iio_dev;
1584 }
1585 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1586
1587 /**
1588 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1589 * @inode: Inode structure for identifying the device in the file system
1590 * @filp: File structure for iio device used to keep and later access
1591 * private data
1592 *
1593 * Return: 0 on success or -EBUSY if the device is already opened
1594 **/
1595 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1596 {
1597 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1598 struct iio_dev, chrdev);
1599
1600 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1601 return -EBUSY;
1602
1603 iio_device_get(indio_dev);
1604
1605 filp->private_data = indio_dev;
1606
1607 return 0;
1608 }
1609
1610 /**
1611 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1612 * @inode: Inode structure pointer for the char device
1613 * @filp: File structure pointer for the char device
1614 *
1615 * Return: 0 for successful release
1616 */
1617 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1618 {
1619 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1620 struct iio_dev, chrdev);
1621 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1622 iio_device_put(indio_dev);
1623
1624 return 0;
1625 }
1626
1627 /* Somewhat of a cross file organization violation - ioctls here are actually
1628 * event related */
1629 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1630 {
1631 struct iio_dev *indio_dev = filp->private_data;
1632 int __user *ip = (int __user *)arg;
1633 int fd;
1634
1635 if (!indio_dev->info)
1636 return -ENODEV;
1637
1638 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1639 fd = iio_event_getfd(indio_dev);
1640 if (fd < 0)
1641 return fd;
1642 if (copy_to_user(ip, &fd, sizeof(fd)))
1643 return -EFAULT;
1644 return 0;
1645 }
1646 return -EINVAL;
1647 }
1648
1649 static const struct file_operations iio_buffer_fileops = {
1650 .read = iio_buffer_read_outer_addr,
1651 .release = iio_chrdev_release,
1652 .open = iio_chrdev_open,
1653 .poll = iio_buffer_poll_addr,
1654 .owner = THIS_MODULE,
1655 .llseek = noop_llseek,
1656 .unlocked_ioctl = iio_ioctl,
1657 .compat_ioctl = compat_ptr_ioctl,
1658 };
1659
1660 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1661 {
1662 int i, j;
1663 const struct iio_chan_spec *channels = indio_dev->channels;
1664
1665 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1666 return 0;
1667
1668 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1669 if (channels[i].scan_index < 0)
1670 continue;
1671 for (j = i + 1; j < indio_dev->num_channels; j++)
1672 if (channels[i].scan_index == channels[j].scan_index) {
1673 dev_err(&indio_dev->dev,
1674 "Duplicate scan index %d\n",
1675 channels[i].scan_index);
1676 return -EINVAL;
1677 }
1678 }
1679
1680 return 0;
1681 }
1682
1683 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1684
1685 int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
1686 {
1687 int ret;
1688
1689 if (!indio_dev->info)
1690 return -EINVAL;
1691
1692 indio_dev->driver_module = this_mod;
1693 /* If the calling driver did not initialize of_node, do it here */
1694 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1695 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1696
1697 indio_dev->label = of_get_property(indio_dev->dev.of_node, "label",
1698 NULL);
1699
1700 ret = iio_check_unique_scan_index(indio_dev);
1701 if (ret < 0)
1702 return ret;
1703
1704 /* configure elements for the chrdev */
1705 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1706
1707 iio_device_register_debugfs(indio_dev);
1708
1709 ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1710 if (ret) {
1711 dev_err(indio_dev->dev.parent,
1712 "Failed to create buffer sysfs interfaces\n");
1713 goto error_unreg_debugfs;
1714 }
1715
1716 ret = iio_device_register_sysfs(indio_dev);
1717 if (ret) {
1718 dev_err(indio_dev->dev.parent,
1719 "Failed to register sysfs interfaces\n");
1720 goto error_buffer_free_sysfs;
1721 }
1722 ret = iio_device_register_eventset(indio_dev);
1723 if (ret) {
1724 dev_err(indio_dev->dev.parent,
1725 "Failed to register event set\n");
1726 goto error_free_sysfs;
1727 }
1728 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1729 iio_device_register_trigger_consumer(indio_dev);
1730
1731 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1732 indio_dev->setup_ops == NULL)
1733 indio_dev->setup_ops = &noop_ring_setup_ops;
1734
1735 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1736
1737 indio_dev->chrdev.owner = this_mod;
1738
1739 ret = cdev_device_add(&indio_dev->chrdev, &indio_dev->dev);
1740 if (ret < 0)
1741 goto error_unreg_eventset;
1742
1743 return 0;
1744
1745 error_unreg_eventset:
1746 iio_device_unregister_eventset(indio_dev);
1747 error_free_sysfs:
1748 iio_device_unregister_sysfs(indio_dev);
1749 error_buffer_free_sysfs:
1750 iio_buffer_free_sysfs_and_mask(indio_dev);
1751 error_unreg_debugfs:
1752 iio_device_unregister_debugfs(indio_dev);
1753 return ret;
1754 }
1755 EXPORT_SYMBOL(__iio_device_register);
1756
1757 /**
1758 * iio_device_unregister() - unregister a device from the IIO subsystem
1759 * @indio_dev: Device structure representing the device.
1760 **/
1761 void iio_device_unregister(struct iio_dev *indio_dev)
1762 {
1763 cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
1764
1765 mutex_lock(&indio_dev->info_exist_lock);
1766
1767 iio_device_unregister_debugfs(indio_dev);
1768
1769 iio_disable_all_buffers(indio_dev);
1770
1771 indio_dev->info = NULL;
1772
1773 iio_device_wakeup_eventset(indio_dev);
1774 iio_buffer_wakeup_poll(indio_dev);
1775
1776 mutex_unlock(&indio_dev->info_exist_lock);
1777
1778 iio_buffer_free_sysfs_and_mask(indio_dev);
1779 }
1780 EXPORT_SYMBOL(iio_device_unregister);
1781
1782 static void devm_iio_device_unreg(struct device *dev, void *res)
1783 {
1784 iio_device_unregister(*(struct iio_dev **)res);
1785 }
1786
1787 int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,
1788 struct module *this_mod)
1789 {
1790 struct iio_dev **ptr;
1791 int ret;
1792
1793 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1794 if (!ptr)
1795 return -ENOMEM;
1796
1797 *ptr = indio_dev;
1798 ret = __iio_device_register(indio_dev, this_mod);
1799 if (!ret)
1800 devres_add(dev, ptr);
1801 else
1802 devres_free(ptr);
1803
1804 return ret;
1805 }
1806 EXPORT_SYMBOL_GPL(__devm_iio_device_register);
1807
1808 /**
1809 * iio_device_claim_direct_mode - Keep device in direct mode
1810 * @indio_dev: the iio_dev associated with the device
1811 *
1812 * If the device is in direct mode it is guaranteed to stay
1813 * that way until iio_device_release_direct_mode() is called.
1814 *
1815 * Use with iio_device_release_direct_mode()
1816 *
1817 * Returns: 0 on success, -EBUSY on failure
1818 */
1819 int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
1820 {
1821 mutex_lock(&indio_dev->mlock);
1822
1823 if (iio_buffer_enabled(indio_dev)) {
1824 mutex_unlock(&indio_dev->mlock);
1825 return -EBUSY;
1826 }
1827 return 0;
1828 }
1829 EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
1830
1831 /**
1832 * iio_device_release_direct_mode - releases claim on direct mode
1833 * @indio_dev: the iio_dev associated with the device
1834 *
1835 * Release the claim. Device is no longer guaranteed to stay
1836 * in direct mode.
1837 *
1838 * Use with iio_device_claim_direct_mode()
1839 */
1840 void iio_device_release_direct_mode(struct iio_dev *indio_dev)
1841 {
1842 mutex_unlock(&indio_dev->mlock);
1843 }
1844 EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
1845
1846 subsys_initcall(iio_init);
1847 module_exit(iio_exit);
1848
1849 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1850 MODULE_DESCRIPTION("Industrial I/O core");
1851 MODULE_LICENSE("GPL");