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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 <linux/iio/iio-opaque.h>
29#include "iio_core.h"
30#include "iio_core_trigger.h"
31#include <linux/iio/sysfs.h>
32#include <linux/iio/events.h>
33#include <linux/iio/buffer.h>
34#include <linux/iio/buffer_impl.h>
35
36/* IDA to assign each registered device a unique id */
37static DEFINE_IDA(iio_ida);
38
39static dev_t iio_devt;
40
41#define IIO_DEV_MAX 256
42struct bus_type iio_bus_type = {
43 .name = "iio",
44};
45EXPORT_SYMBOL(iio_bus_type);
46
47static struct dentry *iio_debugfs_dentry;
48
49static const char * const iio_direction[] = {
50 [0] = "in",
51 [1] = "out",
52};
53
54static const char * const iio_chan_type_name_spec[] = {
55 [IIO_VOLTAGE] = "voltage",
56 [IIO_CURRENT] = "current",
57 [IIO_POWER] = "power",
58 [IIO_ACCEL] = "accel",
59 [IIO_ANGL_VEL] = "anglvel",
60 [IIO_MAGN] = "magn",
61 [IIO_LIGHT] = "illuminance",
62 [IIO_INTENSITY] = "intensity",
63 [IIO_PROXIMITY] = "proximity",
64 [IIO_TEMP] = "temp",
65 [IIO_INCLI] = "incli",
66 [IIO_ROT] = "rot",
67 [IIO_ANGL] = "angl",
68 [IIO_TIMESTAMP] = "timestamp",
69 [IIO_CAPACITANCE] = "capacitance",
70 [IIO_ALTVOLTAGE] = "altvoltage",
71 [IIO_CCT] = "cct",
72 [IIO_PRESSURE] = "pressure",
73 [IIO_HUMIDITYRELATIVE] = "humidityrelative",
74 [IIO_ACTIVITY] = "activity",
75 [IIO_STEPS] = "steps",
76 [IIO_ENERGY] = "energy",
77 [IIO_DISTANCE] = "distance",
78 [IIO_VELOCITY] = "velocity",
79 [IIO_CONCENTRATION] = "concentration",
80 [IIO_RESISTANCE] = "resistance",
81 [IIO_PH] = "ph",
82 [IIO_UVINDEX] = "uvindex",
83 [IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",
84 [IIO_COUNT] = "count",
85 [IIO_INDEX] = "index",
86 [IIO_GRAVITY] = "gravity",
87 [IIO_POSITIONRELATIVE] = "positionrelative",
88 [IIO_PHASE] = "phase",
89 [IIO_MASSCONCENTRATION] = "massconcentration",
90};
91
92static const char * const iio_modifier_names[] = {
93 [IIO_MOD_X] = "x",
94 [IIO_MOD_Y] = "y",
95 [IIO_MOD_Z] = "z",
96 [IIO_MOD_X_AND_Y] = "x&y",
97 [IIO_MOD_X_AND_Z] = "x&z",
98 [IIO_MOD_Y_AND_Z] = "y&z",
99 [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
100 [IIO_MOD_X_OR_Y] = "x|y",
101 [IIO_MOD_X_OR_Z] = "x|z",
102 [IIO_MOD_Y_OR_Z] = "y|z",
103 [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
104 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
105 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
106 [IIO_MOD_LIGHT_BOTH] = "both",
107 [IIO_MOD_LIGHT_IR] = "ir",
108 [IIO_MOD_LIGHT_CLEAR] = "clear",
109 [IIO_MOD_LIGHT_RED] = "red",
110 [IIO_MOD_LIGHT_GREEN] = "green",
111 [IIO_MOD_LIGHT_BLUE] = "blue",
112 [IIO_MOD_LIGHT_UV] = "uv",
113 [IIO_MOD_LIGHT_DUV] = "duv",
114 [IIO_MOD_QUATERNION] = "quaternion",
115 [IIO_MOD_TEMP_AMBIENT] = "ambient",
116 [IIO_MOD_TEMP_OBJECT] = "object",
117 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
118 [IIO_MOD_NORTH_TRUE] = "from_north_true",
119 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
120 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
121 [IIO_MOD_RUNNING] = "running",
122 [IIO_MOD_JOGGING] = "jogging",
123 [IIO_MOD_WALKING] = "walking",
124 [IIO_MOD_STILL] = "still",
125 [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
126 [IIO_MOD_I] = "i",
127 [IIO_MOD_Q] = "q",
128 [IIO_MOD_CO2] = "co2",
129 [IIO_MOD_VOC] = "voc",
130 [IIO_MOD_PM1] = "pm1",
131 [IIO_MOD_PM2P5] = "pm2p5",
132 [IIO_MOD_PM4] = "pm4",
133 [IIO_MOD_PM10] = "pm10",
134 [IIO_MOD_ETHANOL] = "ethanol",
135 [IIO_MOD_H2] = "h2",
136 [IIO_MOD_O2] = "o2",
137};
138
139/* relies on pairs of these shared then separate */
140static const char * const iio_chan_info_postfix[] = {
141 [IIO_CHAN_INFO_RAW] = "raw",
142 [IIO_CHAN_INFO_PROCESSED] = "input",
143 [IIO_CHAN_INFO_SCALE] = "scale",
144 [IIO_CHAN_INFO_OFFSET] = "offset",
145 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
146 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
147 [IIO_CHAN_INFO_PEAK] = "peak_raw",
148 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
149 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
150 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
151 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
152 = "filter_low_pass_3db_frequency",
153 [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
154 = "filter_high_pass_3db_frequency",
155 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
156 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
157 [IIO_CHAN_INFO_PHASE] = "phase",
158 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
159 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
160 [IIO_CHAN_INFO_HYSTERESIS_RELATIVE] = "hysteresis_relative",
161 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
162 [IIO_CHAN_INFO_ENABLE] = "en",
163 [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
164 [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
165 [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
166 [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
167 [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
168 [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
169 [IIO_CHAN_INFO_THERMOCOUPLE_TYPE] = "thermocouple_type",
170 [IIO_CHAN_INFO_CALIBAMBIENT] = "calibambient",
171};
172/**
173 * iio_device_id() - query the unique ID for the device
174 * @indio_dev: Device structure whose ID is being queried
175 *
176 * The IIO device ID is a unique index used for example for the naming
177 * of the character device /dev/iio\:device[ID]
178 */
179int iio_device_id(struct iio_dev *indio_dev)
180{
181 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
182
183 return iio_dev_opaque->id;
184}
185EXPORT_SYMBOL_GPL(iio_device_id);
186
187/**
188 * iio_sysfs_match_string_with_gaps - matches given string in an array with gaps
189 * @array: array of strings
190 * @n: number of strings in the array
191 * @str: string to match with
192 *
193 * Returns index of @str in the @array or -EINVAL, similar to match_string().
194 * Uses sysfs_streq instead of strcmp for matching.
195 *
196 * This routine will look for a string in an array of strings.
197 * The search will continue until the element is found or the n-th element
198 * is reached, regardless of any NULL elements in the array.
199 */
200static int iio_sysfs_match_string_with_gaps(const char * const *array, size_t n,
201 const char *str)
202{
203 const char *item;
204 int index;
205
206 for (index = 0; index < n; index++) {
207 item = array[index];
208 if (!item)
209 continue;
210 if (sysfs_streq(item, str))
211 return index;
212 }
213
214 return -EINVAL;
215}
216
217#if defined(CONFIG_DEBUG_FS)
218/*
219 * There's also a CONFIG_DEBUG_FS guard in include/linux/iio/iio.h for
220 * iio_get_debugfs_dentry() to make it inline if CONFIG_DEBUG_FS is undefined
221 */
222struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
223{
224 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
225 return iio_dev_opaque->debugfs_dentry;
226}
227EXPORT_SYMBOL_GPL(iio_get_debugfs_dentry);
228#endif
229
230/**
231 * iio_find_channel_from_si() - get channel from its scan index
232 * @indio_dev: device
233 * @si: scan index to match
234 */
235const struct iio_chan_spec
236*iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
237{
238 int i;
239
240 for (i = 0; i < indio_dev->num_channels; i++)
241 if (indio_dev->channels[i].scan_index == si)
242 return &indio_dev->channels[i];
243 return NULL;
244}
245
246/* This turns up an awful lot */
247ssize_t iio_read_const_attr(struct device *dev,
248 struct device_attribute *attr,
249 char *buf)
250{
251 return sysfs_emit(buf, "%s\n", to_iio_const_attr(attr)->string);
252}
253EXPORT_SYMBOL(iio_read_const_attr);
254
255/**
256 * iio_device_set_clock() - Set current timestamping clock for the device
257 * @indio_dev: IIO device structure containing the device
258 * @clock_id: timestamping clock posix identifier to set.
259 */
260int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id)
261{
262 int ret;
263 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
264 const struct iio_event_interface *ev_int = iio_dev_opaque->event_interface;
265
266 ret = mutex_lock_interruptible(&indio_dev->mlock);
267 if (ret)
268 return ret;
269 if ((ev_int && iio_event_enabled(ev_int)) ||
270 iio_buffer_enabled(indio_dev)) {
271 mutex_unlock(&indio_dev->mlock);
272 return -EBUSY;
273 }
274 iio_dev_opaque->clock_id = clock_id;
275 mutex_unlock(&indio_dev->mlock);
276
277 return 0;
278}
279EXPORT_SYMBOL(iio_device_set_clock);
280
281/**
282 * iio_device_get_clock() - Retrieve current timestamping clock for the device
283 * @indio_dev: IIO device structure containing the device
284 */
285clockid_t iio_device_get_clock(const struct iio_dev *indio_dev)
286{
287 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
288
289 return iio_dev_opaque->clock_id;
290}
291EXPORT_SYMBOL(iio_device_get_clock);
292
293/**
294 * iio_get_time_ns() - utility function to get a time stamp for events etc
295 * @indio_dev: device
296 */
297s64 iio_get_time_ns(const struct iio_dev *indio_dev)
298{
299 struct timespec64 tp;
300
301 switch (iio_device_get_clock(indio_dev)) {
302 case CLOCK_REALTIME:
303 return ktime_get_real_ns();
304 case CLOCK_MONOTONIC:
305 return ktime_get_ns();
306 case CLOCK_MONOTONIC_RAW:
307 return ktime_get_raw_ns();
308 case CLOCK_REALTIME_COARSE:
309 return ktime_to_ns(ktime_get_coarse_real());
310 case CLOCK_MONOTONIC_COARSE:
311 ktime_get_coarse_ts64(&tp);
312 return timespec64_to_ns(&tp);
313 case CLOCK_BOOTTIME:
314 return ktime_get_boottime_ns();
315 case CLOCK_TAI:
316 return ktime_get_clocktai_ns();
317 default:
318 BUG();
319 }
320}
321EXPORT_SYMBOL(iio_get_time_ns);
322
323/**
324 * iio_get_time_res() - utility function to get time stamp clock resolution in
325 * nano seconds.
326 * @indio_dev: device
327 */
328unsigned int iio_get_time_res(const struct iio_dev *indio_dev)
329{
330 switch (iio_device_get_clock(indio_dev)) {
331 case CLOCK_REALTIME:
332 case CLOCK_MONOTONIC:
333 case CLOCK_MONOTONIC_RAW:
334 case CLOCK_BOOTTIME:
335 case CLOCK_TAI:
336 return hrtimer_resolution;
337 case CLOCK_REALTIME_COARSE:
338 case CLOCK_MONOTONIC_COARSE:
339 return LOW_RES_NSEC;
340 default:
341 BUG();
342 }
343}
344EXPORT_SYMBOL(iio_get_time_res);
345
346static int __init iio_init(void)
347{
348 int ret;
349
350 /* Register sysfs bus */
351 ret = bus_register(&iio_bus_type);
352 if (ret < 0) {
353 pr_err("could not register bus type\n");
354 goto error_nothing;
355 }
356
357 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
358 if (ret < 0) {
359 pr_err("failed to allocate char dev region\n");
360 goto error_unregister_bus_type;
361 }
362
363 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
364
365 return 0;
366
367error_unregister_bus_type:
368 bus_unregister(&iio_bus_type);
369error_nothing:
370 return ret;
371}
372
373static void __exit iio_exit(void)
374{
375 if (iio_devt)
376 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
377 bus_unregister(&iio_bus_type);
378 debugfs_remove(iio_debugfs_dentry);
379}
380
381#if defined(CONFIG_DEBUG_FS)
382static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
383 size_t count, loff_t *ppos)
384{
385 struct iio_dev *indio_dev = file->private_data;
386 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
387 unsigned val = 0;
388 int ret;
389
390 if (*ppos > 0)
391 return simple_read_from_buffer(userbuf, count, ppos,
392 iio_dev_opaque->read_buf,
393 iio_dev_opaque->read_buf_len);
394
395 ret = indio_dev->info->debugfs_reg_access(indio_dev,
396 iio_dev_opaque->cached_reg_addr,
397 0, &val);
398 if (ret) {
399 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
400 return ret;
401 }
402
403 iio_dev_opaque->read_buf_len = snprintf(iio_dev_opaque->read_buf,
404 sizeof(iio_dev_opaque->read_buf),
405 "0x%X\n", val);
406
407 return simple_read_from_buffer(userbuf, count, ppos,
408 iio_dev_opaque->read_buf,
409 iio_dev_opaque->read_buf_len);
410}
411
412static ssize_t iio_debugfs_write_reg(struct file *file,
413 const char __user *userbuf, size_t count, loff_t *ppos)
414{
415 struct iio_dev *indio_dev = file->private_data;
416 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
417 unsigned reg, val;
418 char buf[80];
419 int ret;
420
421 count = min_t(size_t, count, (sizeof(buf)-1));
422 if (copy_from_user(buf, userbuf, count))
423 return -EFAULT;
424
425 buf[count] = 0;
426
427 ret = sscanf(buf, "%i %i", ®, &val);
428
429 switch (ret) {
430 case 1:
431 iio_dev_opaque->cached_reg_addr = reg;
432 break;
433 case 2:
434 iio_dev_opaque->cached_reg_addr = reg;
435 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
436 val, NULL);
437 if (ret) {
438 dev_err(indio_dev->dev.parent, "%s: write failed\n",
439 __func__);
440 return ret;
441 }
442 break;
443 default:
444 return -EINVAL;
445 }
446
447 return count;
448}
449
450static const struct file_operations iio_debugfs_reg_fops = {
451 .open = simple_open,
452 .read = iio_debugfs_read_reg,
453 .write = iio_debugfs_write_reg,
454};
455
456static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
457{
458 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
459 debugfs_remove_recursive(iio_dev_opaque->debugfs_dentry);
460}
461
462static void iio_device_register_debugfs(struct iio_dev *indio_dev)
463{
464 struct iio_dev_opaque *iio_dev_opaque;
465
466 if (indio_dev->info->debugfs_reg_access == NULL)
467 return;
468
469 if (!iio_debugfs_dentry)
470 return;
471
472 iio_dev_opaque = to_iio_dev_opaque(indio_dev);
473
474 iio_dev_opaque->debugfs_dentry =
475 debugfs_create_dir(dev_name(&indio_dev->dev),
476 iio_debugfs_dentry);
477
478 debugfs_create_file("direct_reg_access", 0644,
479 iio_dev_opaque->debugfs_dentry, indio_dev,
480 &iio_debugfs_reg_fops);
481}
482#else
483static void iio_device_register_debugfs(struct iio_dev *indio_dev)
484{
485}
486
487static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
488{
489}
490#endif /* CONFIG_DEBUG_FS */
491
492static ssize_t iio_read_channel_ext_info(struct device *dev,
493 struct device_attribute *attr,
494 char *buf)
495{
496 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
497 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
498 const struct iio_chan_spec_ext_info *ext_info;
499
500 ext_info = &this_attr->c->ext_info[this_attr->address];
501
502 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
503}
504
505static ssize_t iio_write_channel_ext_info(struct device *dev,
506 struct device_attribute *attr,
507 const char *buf,
508 size_t len)
509{
510 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
511 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
512 const struct iio_chan_spec_ext_info *ext_info;
513
514 ext_info = &this_attr->c->ext_info[this_attr->address];
515
516 return ext_info->write(indio_dev, ext_info->private,
517 this_attr->c, buf, len);
518}
519
520ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
521 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
522{
523 const struct iio_enum *e = (const struct iio_enum *)priv;
524 unsigned int i;
525 size_t len = 0;
526
527 if (!e->num_items)
528 return 0;
529
530 for (i = 0; i < e->num_items; ++i) {
531 if (!e->items[i])
532 continue;
533 len += sysfs_emit_at(buf, len, "%s ", e->items[i]);
534 }
535
536 /* replace last space with a newline */
537 buf[len - 1] = '\n';
538
539 return len;
540}
541EXPORT_SYMBOL_GPL(iio_enum_available_read);
542
543ssize_t iio_enum_read(struct iio_dev *indio_dev,
544 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
545{
546 const struct iio_enum *e = (const struct iio_enum *)priv;
547 int i;
548
549 if (!e->get)
550 return -EINVAL;
551
552 i = e->get(indio_dev, chan);
553 if (i < 0)
554 return i;
555 else if (i >= e->num_items || !e->items[i])
556 return -EINVAL;
557
558 return sysfs_emit(buf, "%s\n", e->items[i]);
559}
560EXPORT_SYMBOL_GPL(iio_enum_read);
561
562ssize_t iio_enum_write(struct iio_dev *indio_dev,
563 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
564 size_t len)
565{
566 const struct iio_enum *e = (const struct iio_enum *)priv;
567 int ret;
568
569 if (!e->set)
570 return -EINVAL;
571
572 ret = iio_sysfs_match_string_with_gaps(e->items, e->num_items, buf);
573 if (ret < 0)
574 return ret;
575
576 ret = e->set(indio_dev, chan, ret);
577 return ret ? ret : len;
578}
579EXPORT_SYMBOL_GPL(iio_enum_write);
580
581static const struct iio_mount_matrix iio_mount_idmatrix = {
582 .rotation = {
583 "1", "0", "0",
584 "0", "1", "0",
585 "0", "0", "1"
586 }
587};
588
589static int iio_setup_mount_idmatrix(const struct device *dev,
590 struct iio_mount_matrix *matrix)
591{
592 *matrix = iio_mount_idmatrix;
593 dev_info(dev, "mounting matrix not found: using identity...\n");
594 return 0;
595}
596
597ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
598 const struct iio_chan_spec *chan, char *buf)
599{
600 const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
601 priv)(indio_dev, chan);
602
603 if (IS_ERR(mtx))
604 return PTR_ERR(mtx);
605
606 if (!mtx)
607 mtx = &iio_mount_idmatrix;
608
609 return sysfs_emit(buf, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
610 mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
611 mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
612 mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
613}
614EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
615
616/**
617 * iio_read_mount_matrix() - retrieve iio device mounting matrix from
618 * device "mount-matrix" property
619 * @dev: device the mounting matrix property is assigned to
620 * @matrix: where to store retrieved matrix
621 *
622 * If device is assigned no mounting matrix property, a default 3x3 identity
623 * matrix will be filled in.
624 *
625 * Return: 0 if success, or a negative error code on failure.
626 */
627int iio_read_mount_matrix(struct device *dev, struct iio_mount_matrix *matrix)
628{
629 size_t len = ARRAY_SIZE(iio_mount_idmatrix.rotation);
630 int err;
631
632 err = device_property_read_string_array(dev, "mount-matrix", matrix->rotation, len);
633 if (err == len)
634 return 0;
635
636 if (err >= 0)
637 /* Invalid number of matrix entries. */
638 return -EINVAL;
639
640 if (err != -EINVAL)
641 /* Invalid matrix declaration format. */
642 return err;
643
644 /* Matrix was not declared at all: fallback to identity. */
645 return iio_setup_mount_idmatrix(dev, matrix);
646}
647EXPORT_SYMBOL(iio_read_mount_matrix);
648
649static ssize_t __iio_format_value(char *buf, size_t offset, unsigned int type,
650 int size, const int *vals)
651{
652 int tmp0, tmp1;
653 s64 tmp2;
654 bool scale_db = false;
655
656 switch (type) {
657 case IIO_VAL_INT:
658 return sysfs_emit_at(buf, offset, "%d", vals[0]);
659 case IIO_VAL_INT_PLUS_MICRO_DB:
660 scale_db = true;
661 fallthrough;
662 case IIO_VAL_INT_PLUS_MICRO:
663 if (vals[1] < 0)
664 return sysfs_emit_at(buf, offset, "-%d.%06u%s",
665 abs(vals[0]), -vals[1],
666 scale_db ? " dB" : "");
667 else
668 return sysfs_emit_at(buf, offset, "%d.%06u%s", vals[0],
669 vals[1], scale_db ? " dB" : "");
670 case IIO_VAL_INT_PLUS_NANO:
671 if (vals[1] < 0)
672 return sysfs_emit_at(buf, offset, "-%d.%09u",
673 abs(vals[0]), -vals[1]);
674 else
675 return sysfs_emit_at(buf, offset, "%d.%09u", vals[0],
676 vals[1]);
677 case IIO_VAL_FRACTIONAL:
678 tmp2 = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
679 tmp1 = vals[1];
680 tmp0 = (int)div_s64_rem(tmp2, 1000000000, &tmp1);
681 if ((tmp2 < 0) && (tmp0 == 0))
682 return sysfs_emit_at(buf, offset, "-0.%09u", abs(tmp1));
683 else
684 return sysfs_emit_at(buf, offset, "%d.%09u", tmp0,
685 abs(tmp1));
686 case IIO_VAL_FRACTIONAL_LOG2:
687 tmp2 = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
688 tmp0 = (int)div_s64_rem(tmp2, 1000000000LL, &tmp1);
689 if (tmp0 == 0 && tmp2 < 0)
690 return sysfs_emit_at(buf, offset, "-0.%09u", abs(tmp1));
691 else
692 return sysfs_emit_at(buf, offset, "%d.%09u", tmp0,
693 abs(tmp1));
694 case IIO_VAL_INT_MULTIPLE:
695 {
696 int i;
697 int l = 0;
698
699 for (i = 0; i < size; ++i)
700 l += sysfs_emit_at(buf, offset + l, "%d ", vals[i]);
701 return l;
702 }
703 case IIO_VAL_CHAR:
704 return sysfs_emit_at(buf, offset, "%c", (char)vals[0]);
705 default:
706 return 0;
707 }
708}
709
710/**
711 * iio_format_value() - Formats a IIO value into its string representation
712 * @buf: The buffer to which the formatted value gets written
713 * which is assumed to be big enough (i.e. PAGE_SIZE).
714 * @type: One of the IIO_VAL_* constants. This decides how the val
715 * and val2 parameters are formatted.
716 * @size: Number of IIO value entries contained in vals
717 * @vals: Pointer to the values, exact meaning depends on the
718 * type parameter.
719 *
720 * Return: 0 by default, a negative number on failure or the
721 * total number of characters written for a type that belongs
722 * to the IIO_VAL_* constant.
723 */
724ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
725{
726 ssize_t len;
727
728 len = __iio_format_value(buf, 0, type, size, vals);
729 if (len >= PAGE_SIZE - 1)
730 return -EFBIG;
731
732 return len + sysfs_emit_at(buf, len, "\n");
733}
734EXPORT_SYMBOL_GPL(iio_format_value);
735
736static ssize_t iio_read_channel_label(struct device *dev,
737 struct device_attribute *attr,
738 char *buf)
739{
740 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
741 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
742
743 if (!indio_dev->info->read_label)
744 return -EINVAL;
745
746 return indio_dev->info->read_label(indio_dev, this_attr->c, buf);
747}
748
749static ssize_t iio_read_channel_info(struct device *dev,
750 struct device_attribute *attr,
751 char *buf)
752{
753 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
754 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
755 int vals[INDIO_MAX_RAW_ELEMENTS];
756 int ret;
757 int val_len = 2;
758
759 if (indio_dev->info->read_raw_multi)
760 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
761 INDIO_MAX_RAW_ELEMENTS,
762 vals, &val_len,
763 this_attr->address);
764 else
765 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
766 &vals[0], &vals[1], this_attr->address);
767
768 if (ret < 0)
769 return ret;
770
771 return iio_format_value(buf, ret, val_len, vals);
772}
773
774static ssize_t iio_format_list(char *buf, const int *vals, int type, int length,
775 const char *prefix, const char *suffix)
776{
777 ssize_t len;
778 int stride;
779 int i;
780
781 switch (type) {
782 case IIO_VAL_INT:
783 stride = 1;
784 break;
785 default:
786 stride = 2;
787 break;
788 }
789
790 len = sysfs_emit(buf, prefix);
791
792 for (i = 0; i <= length - stride; i += stride) {
793 if (i != 0) {
794 len += sysfs_emit_at(buf, len, " ");
795 if (len >= PAGE_SIZE)
796 return -EFBIG;
797 }
798
799 len += __iio_format_value(buf, len, type, stride, &vals[i]);
800 if (len >= PAGE_SIZE)
801 return -EFBIG;
802 }
803
804 len += sysfs_emit_at(buf, len, "%s\n", suffix);
805
806 return len;
807}
808
809static ssize_t iio_format_avail_list(char *buf, const int *vals,
810 int type, int length)
811{
812
813 return iio_format_list(buf, vals, type, length, "", "");
814}
815
816static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
817{
818 return iio_format_list(buf, vals, type, 3, "[", "]");
819}
820
821static ssize_t iio_read_channel_info_avail(struct device *dev,
822 struct device_attribute *attr,
823 char *buf)
824{
825 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
826 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
827 const int *vals;
828 int ret;
829 int length;
830 int type;
831
832 ret = indio_dev->info->read_avail(indio_dev, this_attr->c,
833 &vals, &type, &length,
834 this_attr->address);
835
836 if (ret < 0)
837 return ret;
838 switch (ret) {
839 case IIO_AVAIL_LIST:
840 return iio_format_avail_list(buf, vals, type, length);
841 case IIO_AVAIL_RANGE:
842 return iio_format_avail_range(buf, vals, type);
843 default:
844 return -EINVAL;
845 }
846}
847
848/**
849 * __iio_str_to_fixpoint() - Parse a fixed-point number from a string
850 * @str: The string to parse
851 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
852 * @integer: The integer part of the number
853 * @fract: The fractional part of the number
854 * @scale_db: True if this should parse as dB
855 *
856 * Returns 0 on success, or a negative error code if the string could not be
857 * parsed.
858 */
859static int __iio_str_to_fixpoint(const char *str, int fract_mult,
860 int *integer, int *fract, bool scale_db)
861{
862 int i = 0, f = 0;
863 bool integer_part = true, negative = false;
864
865 if (fract_mult == 0) {
866 *fract = 0;
867
868 return kstrtoint(str, 0, integer);
869 }
870
871 if (str[0] == '-') {
872 negative = true;
873 str++;
874 } else if (str[0] == '+') {
875 str++;
876 }
877
878 while (*str) {
879 if ('0' <= *str && *str <= '9') {
880 if (integer_part) {
881 i = i * 10 + *str - '0';
882 } else {
883 f += fract_mult * (*str - '0');
884 fract_mult /= 10;
885 }
886 } else if (*str == '\n') {
887 if (*(str + 1) == '\0')
888 break;
889 else
890 return -EINVAL;
891 } else if (!strncmp(str, " dB", sizeof(" dB") - 1) && scale_db) {
892 /* Ignore the dB suffix */
893 str += sizeof(" dB") - 1;
894 continue;
895 } else if (!strncmp(str, "dB", sizeof("dB") - 1) && scale_db) {
896 /* Ignore the dB suffix */
897 str += sizeof("dB") - 1;
898 continue;
899 } else if (*str == '.' && integer_part) {
900 integer_part = false;
901 } else {
902 return -EINVAL;
903 }
904 str++;
905 }
906
907 if (negative) {
908 if (i)
909 i = -i;
910 else
911 f = -f;
912 }
913
914 *integer = i;
915 *fract = f;
916
917 return 0;
918}
919
920/**
921 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
922 * @str: The string to parse
923 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
924 * @integer: The integer part of the number
925 * @fract: The fractional part of the number
926 *
927 * Returns 0 on success, or a negative error code if the string could not be
928 * parsed.
929 */
930int iio_str_to_fixpoint(const char *str, int fract_mult,
931 int *integer, int *fract)
932{
933 return __iio_str_to_fixpoint(str, fract_mult, integer, fract, false);
934}
935EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
936
937static ssize_t iio_write_channel_info(struct device *dev,
938 struct device_attribute *attr,
939 const char *buf,
940 size_t len)
941{
942 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
943 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
944 int ret, fract_mult = 100000;
945 int integer, fract = 0;
946 bool is_char = false;
947 bool scale_db = false;
948
949 /* Assumes decimal - precision based on number of digits */
950 if (!indio_dev->info->write_raw)
951 return -EINVAL;
952
953 if (indio_dev->info->write_raw_get_fmt)
954 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
955 this_attr->c, this_attr->address)) {
956 case IIO_VAL_INT:
957 fract_mult = 0;
958 break;
959 case IIO_VAL_INT_PLUS_MICRO_DB:
960 scale_db = true;
961 fallthrough;
962 case IIO_VAL_INT_PLUS_MICRO:
963 fract_mult = 100000;
964 break;
965 case IIO_VAL_INT_PLUS_NANO:
966 fract_mult = 100000000;
967 break;
968 case IIO_VAL_CHAR:
969 is_char = true;
970 break;
971 default:
972 return -EINVAL;
973 }
974
975 if (is_char) {
976 char ch;
977
978 if (sscanf(buf, "%c", &ch) != 1)
979 return -EINVAL;
980 integer = ch;
981 } else {
982 ret = __iio_str_to_fixpoint(buf, fract_mult, &integer, &fract,
983 scale_db);
984 if (ret)
985 return ret;
986 }
987
988 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
989 integer, fract, this_attr->address);
990 if (ret)
991 return ret;
992
993 return len;
994}
995
996static
997int __iio_device_attr_init(struct device_attribute *dev_attr,
998 const char *postfix,
999 struct iio_chan_spec const *chan,
1000 ssize_t (*readfunc)(struct device *dev,
1001 struct device_attribute *attr,
1002 char *buf),
1003 ssize_t (*writefunc)(struct device *dev,
1004 struct device_attribute *attr,
1005 const char *buf,
1006 size_t len),
1007 enum iio_shared_by shared_by)
1008{
1009 int ret = 0;
1010 char *name = NULL;
1011 char *full_postfix;
1012 sysfs_attr_init(&dev_attr->attr);
1013
1014 /* Build up postfix of <extend_name>_<modifier>_postfix */
1015 if (chan->modified && (shared_by == IIO_SEPARATE)) {
1016 if (chan->extend_name)
1017 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
1018 iio_modifier_names[chan
1019 ->channel2],
1020 chan->extend_name,
1021 postfix);
1022 else
1023 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
1024 iio_modifier_names[chan
1025 ->channel2],
1026 postfix);
1027 } else {
1028 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
1029 full_postfix = kstrdup(postfix, GFP_KERNEL);
1030 else
1031 full_postfix = kasprintf(GFP_KERNEL,
1032 "%s_%s",
1033 chan->extend_name,
1034 postfix);
1035 }
1036 if (full_postfix == NULL)
1037 return -ENOMEM;
1038
1039 if (chan->differential) { /* Differential can not have modifier */
1040 switch (shared_by) {
1041 case IIO_SHARED_BY_ALL:
1042 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
1043 break;
1044 case IIO_SHARED_BY_DIR:
1045 name = kasprintf(GFP_KERNEL, "%s_%s",
1046 iio_direction[chan->output],
1047 full_postfix);
1048 break;
1049 case IIO_SHARED_BY_TYPE:
1050 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
1051 iio_direction[chan->output],
1052 iio_chan_type_name_spec[chan->type],
1053 iio_chan_type_name_spec[chan->type],
1054 full_postfix);
1055 break;
1056 case IIO_SEPARATE:
1057 if (!chan->indexed) {
1058 WARN(1, "Differential channels must be indexed\n");
1059 ret = -EINVAL;
1060 goto error_free_full_postfix;
1061 }
1062 name = kasprintf(GFP_KERNEL,
1063 "%s_%s%d-%s%d_%s",
1064 iio_direction[chan->output],
1065 iio_chan_type_name_spec[chan->type],
1066 chan->channel,
1067 iio_chan_type_name_spec[chan->type],
1068 chan->channel2,
1069 full_postfix);
1070 break;
1071 }
1072 } else { /* Single ended */
1073 switch (shared_by) {
1074 case IIO_SHARED_BY_ALL:
1075 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
1076 break;
1077 case IIO_SHARED_BY_DIR:
1078 name = kasprintf(GFP_KERNEL, "%s_%s",
1079 iio_direction[chan->output],
1080 full_postfix);
1081 break;
1082 case IIO_SHARED_BY_TYPE:
1083 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
1084 iio_direction[chan->output],
1085 iio_chan_type_name_spec[chan->type],
1086 full_postfix);
1087 break;
1088
1089 case IIO_SEPARATE:
1090 if (chan->indexed)
1091 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
1092 iio_direction[chan->output],
1093 iio_chan_type_name_spec[chan->type],
1094 chan->channel,
1095 full_postfix);
1096 else
1097 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
1098 iio_direction[chan->output],
1099 iio_chan_type_name_spec[chan->type],
1100 full_postfix);
1101 break;
1102 }
1103 }
1104 if (name == NULL) {
1105 ret = -ENOMEM;
1106 goto error_free_full_postfix;
1107 }
1108 dev_attr->attr.name = name;
1109
1110 if (readfunc) {
1111 dev_attr->attr.mode |= S_IRUGO;
1112 dev_attr->show = readfunc;
1113 }
1114
1115 if (writefunc) {
1116 dev_attr->attr.mode |= S_IWUSR;
1117 dev_attr->store = writefunc;
1118 }
1119
1120error_free_full_postfix:
1121 kfree(full_postfix);
1122
1123 return ret;
1124}
1125
1126static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
1127{
1128 kfree(dev_attr->attr.name);
1129}
1130
1131int __iio_add_chan_devattr(const char *postfix,
1132 struct iio_chan_spec const *chan,
1133 ssize_t (*readfunc)(struct device *dev,
1134 struct device_attribute *attr,
1135 char *buf),
1136 ssize_t (*writefunc)(struct device *dev,
1137 struct device_attribute *attr,
1138 const char *buf,
1139 size_t len),
1140 u64 mask,
1141 enum iio_shared_by shared_by,
1142 struct device *dev,
1143 struct iio_buffer *buffer,
1144 struct list_head *attr_list)
1145{
1146 int ret;
1147 struct iio_dev_attr *iio_attr, *t;
1148
1149 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
1150 if (iio_attr == NULL)
1151 return -ENOMEM;
1152 ret = __iio_device_attr_init(&iio_attr->dev_attr,
1153 postfix, chan,
1154 readfunc, writefunc, shared_by);
1155 if (ret)
1156 goto error_iio_dev_attr_free;
1157 iio_attr->c = chan;
1158 iio_attr->address = mask;
1159 iio_attr->buffer = buffer;
1160 list_for_each_entry(t, attr_list, l)
1161 if (strcmp(t->dev_attr.attr.name,
1162 iio_attr->dev_attr.attr.name) == 0) {
1163 if (shared_by == IIO_SEPARATE)
1164 dev_err(dev, "tried to double register : %s\n",
1165 t->dev_attr.attr.name);
1166 ret = -EBUSY;
1167 goto error_device_attr_deinit;
1168 }
1169 list_add(&iio_attr->l, attr_list);
1170
1171 return 0;
1172
1173error_device_attr_deinit:
1174 __iio_device_attr_deinit(&iio_attr->dev_attr);
1175error_iio_dev_attr_free:
1176 kfree(iio_attr);
1177 return ret;
1178}
1179
1180static int iio_device_add_channel_label(struct iio_dev *indio_dev,
1181 struct iio_chan_spec const *chan)
1182{
1183 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1184 int ret;
1185
1186 if (!indio_dev->info->read_label)
1187 return 0;
1188
1189 ret = __iio_add_chan_devattr("label",
1190 chan,
1191 &iio_read_channel_label,
1192 NULL,
1193 0,
1194 IIO_SEPARATE,
1195 &indio_dev->dev,
1196 NULL,
1197 &iio_dev_opaque->channel_attr_list);
1198 if (ret < 0)
1199 return ret;
1200
1201 return 1;
1202}
1203
1204static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
1205 struct iio_chan_spec const *chan,
1206 enum iio_shared_by shared_by,
1207 const long *infomask)
1208{
1209 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1210 int i, ret, attrcount = 0;
1211
1212 for_each_set_bit(i, infomask, sizeof(*infomask)*8) {
1213 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1214 return -EINVAL;
1215 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
1216 chan,
1217 &iio_read_channel_info,
1218 &iio_write_channel_info,
1219 i,
1220 shared_by,
1221 &indio_dev->dev,
1222 NULL,
1223 &iio_dev_opaque->channel_attr_list);
1224 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1225 continue;
1226 else if (ret < 0)
1227 return ret;
1228 attrcount++;
1229 }
1230
1231 return attrcount;
1232}
1233
1234static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
1235 struct iio_chan_spec const *chan,
1236 enum iio_shared_by shared_by,
1237 const long *infomask)
1238{
1239 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1240 int i, ret, attrcount = 0;
1241 char *avail_postfix;
1242
1243 for_each_set_bit(i, infomask, sizeof(*infomask) * 8) {
1244 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1245 return -EINVAL;
1246 avail_postfix = kasprintf(GFP_KERNEL,
1247 "%s_available",
1248 iio_chan_info_postfix[i]);
1249 if (!avail_postfix)
1250 return -ENOMEM;
1251
1252 ret = __iio_add_chan_devattr(avail_postfix,
1253 chan,
1254 &iio_read_channel_info_avail,
1255 NULL,
1256 i,
1257 shared_by,
1258 &indio_dev->dev,
1259 NULL,
1260 &iio_dev_opaque->channel_attr_list);
1261 kfree(avail_postfix);
1262 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1263 continue;
1264 else if (ret < 0)
1265 return ret;
1266 attrcount++;
1267 }
1268
1269 return attrcount;
1270}
1271
1272static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
1273 struct iio_chan_spec const *chan)
1274{
1275 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1276 int ret, attrcount = 0;
1277 const struct iio_chan_spec_ext_info *ext_info;
1278
1279 if (chan->channel < 0)
1280 return 0;
1281 ret = iio_device_add_info_mask_type(indio_dev, chan,
1282 IIO_SEPARATE,
1283 &chan->info_mask_separate);
1284 if (ret < 0)
1285 return ret;
1286 attrcount += ret;
1287
1288 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1289 IIO_SEPARATE,
1290 &chan->
1291 info_mask_separate_available);
1292 if (ret < 0)
1293 return ret;
1294 attrcount += ret;
1295
1296 ret = iio_device_add_info_mask_type(indio_dev, chan,
1297 IIO_SHARED_BY_TYPE,
1298 &chan->info_mask_shared_by_type);
1299 if (ret < 0)
1300 return ret;
1301 attrcount += ret;
1302
1303 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1304 IIO_SHARED_BY_TYPE,
1305 &chan->
1306 info_mask_shared_by_type_available);
1307 if (ret < 0)
1308 return ret;
1309 attrcount += ret;
1310
1311 ret = iio_device_add_info_mask_type(indio_dev, chan,
1312 IIO_SHARED_BY_DIR,
1313 &chan->info_mask_shared_by_dir);
1314 if (ret < 0)
1315 return ret;
1316 attrcount += ret;
1317
1318 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1319 IIO_SHARED_BY_DIR,
1320 &chan->info_mask_shared_by_dir_available);
1321 if (ret < 0)
1322 return ret;
1323 attrcount += ret;
1324
1325 ret = iio_device_add_info_mask_type(indio_dev, chan,
1326 IIO_SHARED_BY_ALL,
1327 &chan->info_mask_shared_by_all);
1328 if (ret < 0)
1329 return ret;
1330 attrcount += ret;
1331
1332 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1333 IIO_SHARED_BY_ALL,
1334 &chan->info_mask_shared_by_all_available);
1335 if (ret < 0)
1336 return ret;
1337 attrcount += ret;
1338
1339 ret = iio_device_add_channel_label(indio_dev, chan);
1340 if (ret < 0)
1341 return ret;
1342 attrcount += ret;
1343
1344 if (chan->ext_info) {
1345 unsigned int i = 0;
1346 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
1347 ret = __iio_add_chan_devattr(ext_info->name,
1348 chan,
1349 ext_info->read ?
1350 &iio_read_channel_ext_info : NULL,
1351 ext_info->write ?
1352 &iio_write_channel_ext_info : NULL,
1353 i,
1354 ext_info->shared,
1355 &indio_dev->dev,
1356 NULL,
1357 &iio_dev_opaque->channel_attr_list);
1358 i++;
1359 if (ret == -EBUSY && ext_info->shared)
1360 continue;
1361
1362 if (ret)
1363 return ret;
1364
1365 attrcount++;
1366 }
1367 }
1368
1369 return attrcount;
1370}
1371
1372/**
1373 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
1374 * @attr_list: List of IIO device attributes
1375 *
1376 * This function frees the memory allocated for each of the IIO device
1377 * attributes in the list.
1378 */
1379void iio_free_chan_devattr_list(struct list_head *attr_list)
1380{
1381 struct iio_dev_attr *p, *n;
1382
1383 list_for_each_entry_safe(p, n, attr_list, l) {
1384 kfree_const(p->dev_attr.attr.name);
1385 list_del(&p->l);
1386 kfree(p);
1387 }
1388}
1389
1390static ssize_t iio_show_dev_name(struct device *dev,
1391 struct device_attribute *attr,
1392 char *buf)
1393{
1394 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1395 return sysfs_emit(buf, "%s\n", indio_dev->name);
1396}
1397
1398static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
1399
1400static ssize_t iio_show_dev_label(struct device *dev,
1401 struct device_attribute *attr,
1402 char *buf)
1403{
1404 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1405 return sysfs_emit(buf, "%s\n", indio_dev->label);
1406}
1407
1408static DEVICE_ATTR(label, S_IRUGO, iio_show_dev_label, NULL);
1409
1410static ssize_t iio_show_timestamp_clock(struct device *dev,
1411 struct device_attribute *attr,
1412 char *buf)
1413{
1414 const struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1415 const clockid_t clk = iio_device_get_clock(indio_dev);
1416 const char *name;
1417 ssize_t sz;
1418
1419 switch (clk) {
1420 case CLOCK_REALTIME:
1421 name = "realtime\n";
1422 sz = sizeof("realtime\n");
1423 break;
1424 case CLOCK_MONOTONIC:
1425 name = "monotonic\n";
1426 sz = sizeof("monotonic\n");
1427 break;
1428 case CLOCK_MONOTONIC_RAW:
1429 name = "monotonic_raw\n";
1430 sz = sizeof("monotonic_raw\n");
1431 break;
1432 case CLOCK_REALTIME_COARSE:
1433 name = "realtime_coarse\n";
1434 sz = sizeof("realtime_coarse\n");
1435 break;
1436 case CLOCK_MONOTONIC_COARSE:
1437 name = "monotonic_coarse\n";
1438 sz = sizeof("monotonic_coarse\n");
1439 break;
1440 case CLOCK_BOOTTIME:
1441 name = "boottime\n";
1442 sz = sizeof("boottime\n");
1443 break;
1444 case CLOCK_TAI:
1445 name = "tai\n";
1446 sz = sizeof("tai\n");
1447 break;
1448 default:
1449 BUG();
1450 }
1451
1452 memcpy(buf, name, sz);
1453 return sz;
1454}
1455
1456static ssize_t iio_store_timestamp_clock(struct device *dev,
1457 struct device_attribute *attr,
1458 const char *buf, size_t len)
1459{
1460 clockid_t clk;
1461 int ret;
1462
1463 if (sysfs_streq(buf, "realtime"))
1464 clk = CLOCK_REALTIME;
1465 else if (sysfs_streq(buf, "monotonic"))
1466 clk = CLOCK_MONOTONIC;
1467 else if (sysfs_streq(buf, "monotonic_raw"))
1468 clk = CLOCK_MONOTONIC_RAW;
1469 else if (sysfs_streq(buf, "realtime_coarse"))
1470 clk = CLOCK_REALTIME_COARSE;
1471 else if (sysfs_streq(buf, "monotonic_coarse"))
1472 clk = CLOCK_MONOTONIC_COARSE;
1473 else if (sysfs_streq(buf, "boottime"))
1474 clk = CLOCK_BOOTTIME;
1475 else if (sysfs_streq(buf, "tai"))
1476 clk = CLOCK_TAI;
1477 else
1478 return -EINVAL;
1479
1480 ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);
1481 if (ret)
1482 return ret;
1483
1484 return len;
1485}
1486
1487int iio_device_register_sysfs_group(struct iio_dev *indio_dev,
1488 const struct attribute_group *group)
1489{
1490 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1491 const struct attribute_group **new, **old = iio_dev_opaque->groups;
1492 unsigned int cnt = iio_dev_opaque->groupcounter;
1493
1494 new = krealloc(old, sizeof(*new) * (cnt + 2), GFP_KERNEL);
1495 if (!new)
1496 return -ENOMEM;
1497
1498 new[iio_dev_opaque->groupcounter++] = group;
1499 new[iio_dev_opaque->groupcounter] = NULL;
1500
1501 iio_dev_opaque->groups = new;
1502
1503 return 0;
1504}
1505
1506static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
1507 iio_show_timestamp_clock, iio_store_timestamp_clock);
1508
1509static int iio_device_register_sysfs(struct iio_dev *indio_dev)
1510{
1511 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1512 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
1513 struct iio_dev_attr *p;
1514 struct attribute **attr, *clk = NULL;
1515
1516 /* First count elements in any existing group */
1517 if (indio_dev->info->attrs) {
1518 attr = indio_dev->info->attrs->attrs;
1519 while (*attr++ != NULL)
1520 attrcount_orig++;
1521 }
1522 attrcount = attrcount_orig;
1523 /*
1524 * New channel registration method - relies on the fact a group does
1525 * not need to be initialized if its name is NULL.
1526 */
1527 if (indio_dev->channels)
1528 for (i = 0; i < indio_dev->num_channels; i++) {
1529 const struct iio_chan_spec *chan =
1530 &indio_dev->channels[i];
1531
1532 if (chan->type == IIO_TIMESTAMP)
1533 clk = &dev_attr_current_timestamp_clock.attr;
1534
1535 ret = iio_device_add_channel_sysfs(indio_dev, chan);
1536 if (ret < 0)
1537 goto error_clear_attrs;
1538 attrcount += ret;
1539 }
1540
1541 if (iio_dev_opaque->event_interface)
1542 clk = &dev_attr_current_timestamp_clock.attr;
1543
1544 if (indio_dev->name)
1545 attrcount++;
1546 if (indio_dev->label)
1547 attrcount++;
1548 if (clk)
1549 attrcount++;
1550
1551 iio_dev_opaque->chan_attr_group.attrs =
1552 kcalloc(attrcount + 1,
1553 sizeof(iio_dev_opaque->chan_attr_group.attrs[0]),
1554 GFP_KERNEL);
1555 if (iio_dev_opaque->chan_attr_group.attrs == NULL) {
1556 ret = -ENOMEM;
1557 goto error_clear_attrs;
1558 }
1559 /* Copy across original attributes */
1560 if (indio_dev->info->attrs) {
1561 memcpy(iio_dev_opaque->chan_attr_group.attrs,
1562 indio_dev->info->attrs->attrs,
1563 sizeof(iio_dev_opaque->chan_attr_group.attrs[0])
1564 *attrcount_orig);
1565 iio_dev_opaque->chan_attr_group.is_visible =
1566 indio_dev->info->attrs->is_visible;
1567 }
1568 attrn = attrcount_orig;
1569 /* Add all elements from the list. */
1570 list_for_each_entry(p, &iio_dev_opaque->channel_attr_list, l)
1571 iio_dev_opaque->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
1572 if (indio_dev->name)
1573 iio_dev_opaque->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
1574 if (indio_dev->label)
1575 iio_dev_opaque->chan_attr_group.attrs[attrn++] = &dev_attr_label.attr;
1576 if (clk)
1577 iio_dev_opaque->chan_attr_group.attrs[attrn++] = clk;
1578
1579 ret = iio_device_register_sysfs_group(indio_dev,
1580 &iio_dev_opaque->chan_attr_group);
1581 if (ret)
1582 goto error_clear_attrs;
1583
1584 return 0;
1585
1586error_clear_attrs:
1587 iio_free_chan_devattr_list(&iio_dev_opaque->channel_attr_list);
1588
1589 return ret;
1590}
1591
1592static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
1593{
1594 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1595
1596 iio_free_chan_devattr_list(&iio_dev_opaque->channel_attr_list);
1597 kfree(iio_dev_opaque->chan_attr_group.attrs);
1598 iio_dev_opaque->chan_attr_group.attrs = NULL;
1599 kfree(iio_dev_opaque->groups);
1600}
1601
1602static void iio_dev_release(struct device *device)
1603{
1604 struct iio_dev *indio_dev = dev_to_iio_dev(device);
1605 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1606
1607 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1608 iio_device_unregister_trigger_consumer(indio_dev);
1609 iio_device_unregister_eventset(indio_dev);
1610 iio_device_unregister_sysfs(indio_dev);
1611
1612 iio_device_detach_buffers(indio_dev);
1613
1614 ida_simple_remove(&iio_ida, iio_dev_opaque->id);
1615 kfree(iio_dev_opaque);
1616}
1617
1618struct device_type iio_device_type = {
1619 .name = "iio_device",
1620 .release = iio_dev_release,
1621};
1622
1623/**
1624 * iio_device_alloc() - allocate an iio_dev from a driver
1625 * @parent: Parent device.
1626 * @sizeof_priv: Space to allocate for private structure.
1627 **/
1628struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv)
1629{
1630 struct iio_dev_opaque *iio_dev_opaque;
1631 struct iio_dev *indio_dev;
1632 size_t alloc_size;
1633
1634 alloc_size = sizeof(struct iio_dev_opaque);
1635 if (sizeof_priv) {
1636 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1637 alloc_size += sizeof_priv;
1638 }
1639
1640 iio_dev_opaque = kzalloc(alloc_size, GFP_KERNEL);
1641 if (!iio_dev_opaque)
1642 return NULL;
1643
1644 indio_dev = &iio_dev_opaque->indio_dev;
1645 indio_dev->priv = (char *)iio_dev_opaque +
1646 ALIGN(sizeof(struct iio_dev_opaque), IIO_ALIGN);
1647
1648 indio_dev->dev.parent = parent;
1649 indio_dev->dev.type = &iio_device_type;
1650 indio_dev->dev.bus = &iio_bus_type;
1651 device_initialize(&indio_dev->dev);
1652 iio_device_set_drvdata(indio_dev, (void *)indio_dev);
1653 mutex_init(&indio_dev->mlock);
1654 mutex_init(&iio_dev_opaque->info_exist_lock);
1655 INIT_LIST_HEAD(&iio_dev_opaque->channel_attr_list);
1656
1657 iio_dev_opaque->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1658 if (iio_dev_opaque->id < 0) {
1659 /* cannot use a dev_err as the name isn't available */
1660 pr_err("failed to get device id\n");
1661 kfree(iio_dev_opaque);
1662 return NULL;
1663 }
1664 dev_set_name(&indio_dev->dev, "iio:device%d", iio_dev_opaque->id);
1665 INIT_LIST_HEAD(&iio_dev_opaque->buffer_list);
1666 INIT_LIST_HEAD(&iio_dev_opaque->ioctl_handlers);
1667
1668 return indio_dev;
1669}
1670EXPORT_SYMBOL(iio_device_alloc);
1671
1672/**
1673 * iio_device_free() - free an iio_dev from a driver
1674 * @dev: the iio_dev associated with the device
1675 **/
1676void iio_device_free(struct iio_dev *dev)
1677{
1678 if (dev)
1679 put_device(&dev->dev);
1680}
1681EXPORT_SYMBOL(iio_device_free);
1682
1683static void devm_iio_device_release(void *iio_dev)
1684{
1685 iio_device_free(iio_dev);
1686}
1687
1688/**
1689 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1690 * @parent: Device to allocate iio_dev for, and parent for this IIO device
1691 * @sizeof_priv: Space to allocate for private structure.
1692 *
1693 * Managed iio_device_alloc. iio_dev allocated with this function is
1694 * automatically freed on driver detach.
1695 *
1696 * RETURNS:
1697 * Pointer to allocated iio_dev on success, NULL on failure.
1698 */
1699struct iio_dev *devm_iio_device_alloc(struct device *parent, int sizeof_priv)
1700{
1701 struct iio_dev *iio_dev;
1702 int ret;
1703
1704 iio_dev = iio_device_alloc(parent, sizeof_priv);
1705 if (!iio_dev)
1706 return NULL;
1707
1708 ret = devm_add_action_or_reset(parent, devm_iio_device_release,
1709 iio_dev);
1710 if (ret)
1711 return NULL;
1712
1713 return iio_dev;
1714}
1715EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1716
1717/**
1718 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1719 * @inode: Inode structure for identifying the device in the file system
1720 * @filp: File structure for iio device used to keep and later access
1721 * private data
1722 *
1723 * Return: 0 on success or -EBUSY if the device is already opened
1724 **/
1725static int iio_chrdev_open(struct inode *inode, struct file *filp)
1726{
1727 struct iio_dev_opaque *iio_dev_opaque =
1728 container_of(inode->i_cdev, struct iio_dev_opaque, chrdev);
1729 struct iio_dev *indio_dev = &iio_dev_opaque->indio_dev;
1730 struct iio_dev_buffer_pair *ib;
1731
1732 if (test_and_set_bit(IIO_BUSY_BIT_POS, &iio_dev_opaque->flags))
1733 return -EBUSY;
1734
1735 iio_device_get(indio_dev);
1736
1737 ib = kmalloc(sizeof(*ib), GFP_KERNEL);
1738 if (!ib) {
1739 iio_device_put(indio_dev);
1740 clear_bit(IIO_BUSY_BIT_POS, &iio_dev_opaque->flags);
1741 return -ENOMEM;
1742 }
1743
1744 ib->indio_dev = indio_dev;
1745 ib->buffer = indio_dev->buffer;
1746
1747 filp->private_data = ib;
1748
1749 return 0;
1750}
1751
1752/**
1753 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1754 * @inode: Inode structure pointer for the char device
1755 * @filp: File structure pointer for the char device
1756 *
1757 * Return: 0 for successful release
1758 */
1759static int iio_chrdev_release(struct inode *inode, struct file *filp)
1760{
1761 struct iio_dev_buffer_pair *ib = filp->private_data;
1762 struct iio_dev_opaque *iio_dev_opaque =
1763 container_of(inode->i_cdev, struct iio_dev_opaque, chrdev);
1764 struct iio_dev *indio_dev = &iio_dev_opaque->indio_dev;
1765 kfree(ib);
1766 clear_bit(IIO_BUSY_BIT_POS, &iio_dev_opaque->flags);
1767 iio_device_put(indio_dev);
1768
1769 return 0;
1770}
1771
1772void iio_device_ioctl_handler_register(struct iio_dev *indio_dev,
1773 struct iio_ioctl_handler *h)
1774{
1775 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1776
1777 list_add_tail(&h->entry, &iio_dev_opaque->ioctl_handlers);
1778}
1779
1780void iio_device_ioctl_handler_unregister(struct iio_ioctl_handler *h)
1781{
1782 list_del(&h->entry);
1783}
1784
1785static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1786{
1787 struct iio_dev_buffer_pair *ib = filp->private_data;
1788 struct iio_dev *indio_dev = ib->indio_dev;
1789 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1790 struct iio_ioctl_handler *h;
1791 int ret = -ENODEV;
1792
1793 mutex_lock(&iio_dev_opaque->info_exist_lock);
1794
1795 /**
1796 * The NULL check here is required to prevent crashing when a device
1797 * is being removed while userspace would still have open file handles
1798 * to try to access this device.
1799 */
1800 if (!indio_dev->info)
1801 goto out_unlock;
1802
1803 list_for_each_entry(h, &iio_dev_opaque->ioctl_handlers, entry) {
1804 ret = h->ioctl(indio_dev, filp, cmd, arg);
1805 if (ret != IIO_IOCTL_UNHANDLED)
1806 break;
1807 }
1808
1809 if (ret == IIO_IOCTL_UNHANDLED)
1810 ret = -ENODEV;
1811
1812out_unlock:
1813 mutex_unlock(&iio_dev_opaque->info_exist_lock);
1814
1815 return ret;
1816}
1817
1818static const struct file_operations iio_buffer_fileops = {
1819 .owner = THIS_MODULE,
1820 .llseek = noop_llseek,
1821 .read = iio_buffer_read_outer_addr,
1822 .poll = iio_buffer_poll_addr,
1823 .unlocked_ioctl = iio_ioctl,
1824 .compat_ioctl = compat_ptr_ioctl,
1825 .open = iio_chrdev_open,
1826 .release = iio_chrdev_release,
1827};
1828
1829static const struct file_operations iio_event_fileops = {
1830 .owner = THIS_MODULE,
1831 .llseek = noop_llseek,
1832 .unlocked_ioctl = iio_ioctl,
1833 .compat_ioctl = compat_ptr_ioctl,
1834 .open = iio_chrdev_open,
1835 .release = iio_chrdev_release,
1836};
1837
1838static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1839{
1840 int i, j;
1841 const struct iio_chan_spec *channels = indio_dev->channels;
1842
1843 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1844 return 0;
1845
1846 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1847 if (channels[i].scan_index < 0)
1848 continue;
1849 for (j = i + 1; j < indio_dev->num_channels; j++)
1850 if (channels[i].scan_index == channels[j].scan_index) {
1851 dev_err(&indio_dev->dev,
1852 "Duplicate scan index %d\n",
1853 channels[i].scan_index);
1854 return -EINVAL;
1855 }
1856 }
1857
1858 return 0;
1859}
1860
1861static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1862
1863int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
1864{
1865 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1866 const char *label;
1867 int ret;
1868
1869 if (!indio_dev->info)
1870 return -EINVAL;
1871
1872 iio_dev_opaque->driver_module = this_mod;
1873 /* If the calling driver did not initialize of_node, do it here */
1874 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1875 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1876
1877 label = of_get_property(indio_dev->dev.of_node, "label", NULL);
1878 if (label)
1879 indio_dev->label = label;
1880
1881 ret = iio_check_unique_scan_index(indio_dev);
1882 if (ret < 0)
1883 return ret;
1884
1885 iio_device_register_debugfs(indio_dev);
1886
1887 ret = iio_buffers_alloc_sysfs_and_mask(indio_dev);
1888 if (ret) {
1889 dev_err(indio_dev->dev.parent,
1890 "Failed to create buffer sysfs interfaces\n");
1891 goto error_unreg_debugfs;
1892 }
1893
1894 ret = iio_device_register_sysfs(indio_dev);
1895 if (ret) {
1896 dev_err(indio_dev->dev.parent,
1897 "Failed to register sysfs interfaces\n");
1898 goto error_buffer_free_sysfs;
1899 }
1900 ret = iio_device_register_eventset(indio_dev);
1901 if (ret) {
1902 dev_err(indio_dev->dev.parent,
1903 "Failed to register event set\n");
1904 goto error_free_sysfs;
1905 }
1906 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1907 iio_device_register_trigger_consumer(indio_dev);
1908
1909 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1910 indio_dev->setup_ops == NULL)
1911 indio_dev->setup_ops = &noop_ring_setup_ops;
1912
1913 if (iio_dev_opaque->attached_buffers_cnt)
1914 cdev_init(&iio_dev_opaque->chrdev, &iio_buffer_fileops);
1915 else if (iio_dev_opaque->event_interface)
1916 cdev_init(&iio_dev_opaque->chrdev, &iio_event_fileops);
1917
1918 if (iio_dev_opaque->attached_buffers_cnt || iio_dev_opaque->event_interface) {
1919 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), iio_dev_opaque->id);
1920 iio_dev_opaque->chrdev.owner = this_mod;
1921 }
1922
1923 /* assign device groups now; they should be all registered now */
1924 indio_dev->dev.groups = iio_dev_opaque->groups;
1925
1926 ret = cdev_device_add(&iio_dev_opaque->chrdev, &indio_dev->dev);
1927 if (ret < 0)
1928 goto error_unreg_eventset;
1929
1930 return 0;
1931
1932error_unreg_eventset:
1933 iio_device_unregister_eventset(indio_dev);
1934error_free_sysfs:
1935 iio_device_unregister_sysfs(indio_dev);
1936error_buffer_free_sysfs:
1937 iio_buffers_free_sysfs_and_mask(indio_dev);
1938error_unreg_debugfs:
1939 iio_device_unregister_debugfs(indio_dev);
1940 return ret;
1941}
1942EXPORT_SYMBOL(__iio_device_register);
1943
1944/**
1945 * iio_device_unregister() - unregister a device from the IIO subsystem
1946 * @indio_dev: Device structure representing the device.
1947 **/
1948void iio_device_unregister(struct iio_dev *indio_dev)
1949{
1950 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
1951
1952 cdev_device_del(&iio_dev_opaque->chrdev, &indio_dev->dev);
1953
1954 mutex_lock(&iio_dev_opaque->info_exist_lock);
1955
1956 iio_device_unregister_debugfs(indio_dev);
1957
1958 iio_disable_all_buffers(indio_dev);
1959
1960 indio_dev->info = NULL;
1961
1962 iio_device_wakeup_eventset(indio_dev);
1963 iio_buffer_wakeup_poll(indio_dev);
1964
1965 mutex_unlock(&iio_dev_opaque->info_exist_lock);
1966
1967 iio_buffers_free_sysfs_and_mask(indio_dev);
1968}
1969EXPORT_SYMBOL(iio_device_unregister);
1970
1971static void devm_iio_device_unreg(void *indio_dev)
1972{
1973 iio_device_unregister(indio_dev);
1974}
1975
1976int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,
1977 struct module *this_mod)
1978{
1979 int ret;
1980
1981 ret = __iio_device_register(indio_dev, this_mod);
1982 if (ret)
1983 return ret;
1984
1985 return devm_add_action_or_reset(dev, devm_iio_device_unreg, indio_dev);
1986}
1987EXPORT_SYMBOL_GPL(__devm_iio_device_register);
1988
1989/**
1990 * iio_device_claim_direct_mode - Keep device in direct mode
1991 * @indio_dev: the iio_dev associated with the device
1992 *
1993 * If the device is in direct mode it is guaranteed to stay
1994 * that way until iio_device_release_direct_mode() is called.
1995 *
1996 * Use with iio_device_release_direct_mode()
1997 *
1998 * Returns: 0 on success, -EBUSY on failure
1999 */
2000int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
2001{
2002 mutex_lock(&indio_dev->mlock);
2003
2004 if (iio_buffer_enabled(indio_dev)) {
2005 mutex_unlock(&indio_dev->mlock);
2006 return -EBUSY;
2007 }
2008 return 0;
2009}
2010EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
2011
2012/**
2013 * iio_device_release_direct_mode - releases claim on direct mode
2014 * @indio_dev: the iio_dev associated with the device
2015 *
2016 * Release the claim. Device is no longer guaranteed to stay
2017 * in direct mode.
2018 *
2019 * Use with iio_device_claim_direct_mode()
2020 */
2021void iio_device_release_direct_mode(struct iio_dev *indio_dev)
2022{
2023 mutex_unlock(&indio_dev->mlock);
2024}
2025EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
2026
2027subsys_initcall(iio_init);
2028module_exit(iio_exit);
2029
2030MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
2031MODULE_DESCRIPTION("Industrial I/O core");
2032MODULE_LICENSE("GPL");