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