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