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arm64: alternatives: add enable parameter to conditional asm macros
[linux/fpc-iii.git] / drivers / iio / industrialio-core.c
blob3524b0de872110d31442060a109c5c4243a3f0cf
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/iio/iio.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
35 /* IDA to assign each registered device a unique id */
36 static DEFINE_IDA(iio_ida);
37
38 static dev_t iio_devt;
39
40 #define IIO_DEV_MAX 256
41 struct bus_type iio_bus_type = {
42 .name = "iio",
43 };
44 EXPORT_SYMBOL(iio_bus_type);
45
46 static struct dentry *iio_debugfs_dentry;
47
48 static const char * const iio_direction[] = {
49 [0] = "in",
50 [1] = "out",
51 };
52
53 static const char * const iio_chan_type_name_spec[] = {
54 [IIO_VOLTAGE] = "voltage",
55 [IIO_CURRENT] = "current",
56 [IIO_POWER] = "power",
57 [IIO_ACCEL] = "accel",
58 [IIO_ANGL_VEL] = "anglvel",
59 [IIO_MAGN] = "magn",
60 [IIO_LIGHT] = "illuminance",
61 [IIO_INTENSITY] = "intensity",
62 [IIO_PROXIMITY] = "proximity",
63 [IIO_TEMP] = "temp",
64 [IIO_INCLI] = "incli",
65 [IIO_ROT] = "rot",
66 [IIO_ANGL] = "angl",
67 [IIO_TIMESTAMP] = "timestamp",
68 [IIO_CAPACITANCE] = "capacitance",
69 [IIO_ALTVOLTAGE] = "altvoltage",
70 [IIO_CCT] = "cct",
71 [IIO_PRESSURE] = "pressure",
72 [IIO_HUMIDITYRELATIVE] = "humidityrelative",
73 [IIO_ACTIVITY] = "activity",
74 [IIO_STEPS] = "steps",
75 [IIO_ENERGY] = "energy",
76 [IIO_DISTANCE] = "distance",
77 [IIO_VELOCITY] = "velocity",
78 };
79
80 static const char * const iio_modifier_names[] = {
81 [IIO_MOD_X] = "x",
82 [IIO_MOD_Y] = "y",
83 [IIO_MOD_Z] = "z",
84 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
85 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
86 [IIO_MOD_LIGHT_BOTH] = "both",
87 [IIO_MOD_LIGHT_IR] = "ir",
88 [IIO_MOD_LIGHT_CLEAR] = "clear",
89 [IIO_MOD_LIGHT_RED] = "red",
90 [IIO_MOD_LIGHT_GREEN] = "green",
91 [IIO_MOD_LIGHT_BLUE] = "blue",
92 [IIO_MOD_QUATERNION] = "quaternion",
93 [IIO_MOD_TEMP_AMBIENT] = "ambient",
94 [IIO_MOD_TEMP_OBJECT] = "object",
95 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
96 [IIO_MOD_NORTH_TRUE] = "from_north_true",
97 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
98 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
99 [IIO_MOD_RUNNING] = "running",
100 [IIO_MOD_JOGGING] = "jogging",
101 [IIO_MOD_WALKING] = "walking",
102 [IIO_MOD_STILL] = "still",
103 [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
104 [IIO_MOD_I] = "i",
105 [IIO_MOD_Q] = "q",
106 };
107
108 /* relies on pairs of these shared then separate */
109 static const char * const iio_chan_info_postfix[] = {
110 [IIO_CHAN_INFO_RAW] = "raw",
111 [IIO_CHAN_INFO_PROCESSED] = "input",
112 [IIO_CHAN_INFO_SCALE] = "scale",
113 [IIO_CHAN_INFO_OFFSET] = "offset",
114 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
115 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
116 [IIO_CHAN_INFO_PEAK] = "peak_raw",
117 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
118 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
119 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
120 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
121 = "filter_low_pass_3db_frequency",
122 [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
123 = "filter_high_pass_3db_frequency",
124 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
125 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
126 [IIO_CHAN_INFO_PHASE] = "phase",
127 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
128 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
129 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
130 [IIO_CHAN_INFO_ENABLE] = "en",
131 [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
132 [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
133 [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
134 [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
135 [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
136 [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
137 };
138
139 /**
140 * iio_find_channel_from_si() - get channel from its scan index
141 * @indio_dev: device
142 * @si: scan index to match
143 */
144 const struct iio_chan_spec
145 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
146 {
147 int i;
148
149 for (i = 0; i < indio_dev->num_channels; i++)
150 if (indio_dev->channels[i].scan_index == si)
151 return &indio_dev->channels[i];
152 return NULL;
153 }
154
155 /* This turns up an awful lot */
156 ssize_t iio_read_const_attr(struct device *dev,
157 struct device_attribute *attr,
158 char *buf)
159 {
160 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
161 }
162 EXPORT_SYMBOL(iio_read_const_attr);
163
164 static int __init iio_init(void)
165 {
166 int ret;
167
168 /* Register sysfs bus */
169 ret = bus_register(&iio_bus_type);
170 if (ret < 0) {
171 pr_err("could not register bus type\n");
172 goto error_nothing;
173 }
174
175 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
176 if (ret < 0) {
177 pr_err("failed to allocate char dev region\n");
178 goto error_unregister_bus_type;
179 }
180
181 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
182
183 return 0;
184
185 error_unregister_bus_type:
186 bus_unregister(&iio_bus_type);
187 error_nothing:
188 return ret;
189 }
190
191 static void __exit iio_exit(void)
192 {
193 if (iio_devt)
194 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
195 bus_unregister(&iio_bus_type);
196 debugfs_remove(iio_debugfs_dentry);
197 }
198
199 #if defined(CONFIG_DEBUG_FS)
200 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
201 size_t count, loff_t *ppos)
202 {
203 struct iio_dev *indio_dev = file->private_data;
204 char buf[20];
205 unsigned val = 0;
206 ssize_t len;
207 int ret;
208
209 ret = indio_dev->info->debugfs_reg_access(indio_dev,
210 indio_dev->cached_reg_addr,
211 0, &val);
212 if (ret)
213 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
214
215 len = snprintf(buf, sizeof(buf), "0x%X\n", val);
216
217 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
218 }
219
220 static ssize_t iio_debugfs_write_reg(struct file *file,
221 const char __user *userbuf, size_t count, loff_t *ppos)
222 {
223 struct iio_dev *indio_dev = file->private_data;
224 unsigned reg, val;
225 char buf[80];
226 int ret;
227
228 count = min_t(size_t, count, (sizeof(buf)-1));
229 if (copy_from_user(buf, userbuf, count))
230 return -EFAULT;
231
232 buf[count] = 0;
233
234 ret = sscanf(buf, "%i %i", &reg, &val);
235
236 switch (ret) {
237 case 1:
238 indio_dev->cached_reg_addr = reg;
239 break;
240 case 2:
241 indio_dev->cached_reg_addr = reg;
242 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
243 val, NULL);
244 if (ret) {
245 dev_err(indio_dev->dev.parent, "%s: write failed\n",
246 __func__);
247 return ret;
248 }
249 break;
250 default:
251 return -EINVAL;
252 }
253
254 return count;
255 }
256
257 static const struct file_operations iio_debugfs_reg_fops = {
258 .open = simple_open,
259 .read = iio_debugfs_read_reg,
260 .write = iio_debugfs_write_reg,
261 };
262
263 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
264 {
265 debugfs_remove_recursive(indio_dev->debugfs_dentry);
266 }
267
268 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
269 {
270 struct dentry *d;
271
272 if (indio_dev->info->debugfs_reg_access == NULL)
273 return 0;
274
275 if (!iio_debugfs_dentry)
276 return 0;
277
278 indio_dev->debugfs_dentry =
279 debugfs_create_dir(dev_name(&indio_dev->dev),
280 iio_debugfs_dentry);
281 if (indio_dev->debugfs_dentry == NULL) {
282 dev_warn(indio_dev->dev.parent,
283 "Failed to create debugfs directory\n");
284 return -EFAULT;
285 }
286
287 d = debugfs_create_file("direct_reg_access", 0644,
288 indio_dev->debugfs_dentry,
289 indio_dev, &iio_debugfs_reg_fops);
290 if (!d) {
291 iio_device_unregister_debugfs(indio_dev);
292 return -ENOMEM;
293 }
294
295 return 0;
296 }
297 #else
298 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
299 {
300 return 0;
301 }
302
303 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
304 {
305 }
306 #endif /* CONFIG_DEBUG_FS */
307
308 static ssize_t iio_read_channel_ext_info(struct device *dev,
309 struct device_attribute *attr,
310 char *buf)
311 {
312 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
313 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
314 const struct iio_chan_spec_ext_info *ext_info;
315
316 ext_info = &this_attr->c->ext_info[this_attr->address];
317
318 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
319 }
320
321 static ssize_t iio_write_channel_ext_info(struct device *dev,
322 struct device_attribute *attr,
323 const char *buf,
324 size_t len)
325 {
326 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
327 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
328 const struct iio_chan_spec_ext_info *ext_info;
329
330 ext_info = &this_attr->c->ext_info[this_attr->address];
331
332 return ext_info->write(indio_dev, ext_info->private,
333 this_attr->c, buf, len);
334 }
335
336 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
337 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
338 {
339 const struct iio_enum *e = (const struct iio_enum *)priv;
340 unsigned int i;
341 size_t len = 0;
342
343 if (!e->num_items)
344 return 0;
345
346 for (i = 0; i < e->num_items; ++i)
347 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
348
349 /* replace last space with a newline */
350 buf[len - 1] = '\n';
351
352 return len;
353 }
354 EXPORT_SYMBOL_GPL(iio_enum_available_read);
355
356 ssize_t iio_enum_read(struct iio_dev *indio_dev,
357 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
358 {
359 const struct iio_enum *e = (const struct iio_enum *)priv;
360 int i;
361
362 if (!e->get)
363 return -EINVAL;
364
365 i = e->get(indio_dev, chan);
366 if (i < 0)
367 return i;
368 else if (i >= e->num_items)
369 return -EINVAL;
370
371 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
372 }
373 EXPORT_SYMBOL_GPL(iio_enum_read);
374
375 ssize_t iio_enum_write(struct iio_dev *indio_dev,
376 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
377 size_t len)
378 {
379 const struct iio_enum *e = (const struct iio_enum *)priv;
380 unsigned int i;
381 int ret;
382
383 if (!e->set)
384 return -EINVAL;
385
386 for (i = 0; i < e->num_items; i++) {
387 if (sysfs_streq(buf, e->items[i]))
388 break;
389 }
390
391 if (i == e->num_items)
392 return -EINVAL;
393
394 ret = e->set(indio_dev, chan, i);
395 return ret ? ret : len;
396 }
397 EXPORT_SYMBOL_GPL(iio_enum_write);
398
399 /**
400 * iio_format_value() - Formats a IIO value into its string representation
401 * @buf: The buffer to which the formated value gets written
402 * @type: One of the IIO_VAL_... constants. This decides how the val and val2
403 * parameters are formatted.
404 * @vals: pointer to the values, exact meaning depends on the type parameter.
405 */
406 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
407 {
408 unsigned long long tmp;
409 bool scale_db = false;
410
411 switch (type) {
412 case IIO_VAL_INT:
413 return sprintf(buf, "%d\n", vals[0]);
414 case IIO_VAL_INT_PLUS_MICRO_DB:
415 scale_db = true;
416 case IIO_VAL_INT_PLUS_MICRO:
417 if (vals[1] < 0)
418 return sprintf(buf, "-%ld.%06u%s\n", abs(vals[0]),
419 -vals[1],
420 scale_db ? " dB" : "");
421 else
422 return sprintf(buf, "%d.%06u%s\n", vals[0], vals[1],
423 scale_db ? " dB" : "");
424 case IIO_VAL_INT_PLUS_NANO:
425 if (vals[1] < 0)
426 return sprintf(buf, "-%ld.%09u\n", abs(vals[0]),
427 -vals[1]);
428 else
429 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
430 case IIO_VAL_FRACTIONAL:
431 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
432 vals[1] = do_div(tmp, 1000000000LL);
433 vals[0] = tmp;
434 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
435 case IIO_VAL_FRACTIONAL_LOG2:
436 tmp = (s64)vals[0] * 1000000000LL >> vals[1];
437 vals[1] = do_div(tmp, 1000000000LL);
438 vals[0] = tmp;
439 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
440 case IIO_VAL_INT_MULTIPLE:
441 {
442 int i;
443 int len = 0;
444
445 for (i = 0; i < size; ++i)
446 len += snprintf(&buf[len], PAGE_SIZE - len, "%d ",
447 vals[i]);
448 len += snprintf(&buf[len], PAGE_SIZE - len, "\n");
449 return len;
450 }
451 default:
452 return 0;
453 }
454 }
455
456 static ssize_t iio_read_channel_info(struct device *dev,
457 struct device_attribute *attr,
458 char *buf)
459 {
460 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
461 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
462 int vals[INDIO_MAX_RAW_ELEMENTS];
463 int ret;
464 int val_len = 2;
465
466 if (indio_dev->info->read_raw_multi)
467 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
468 INDIO_MAX_RAW_ELEMENTS,
469 vals, &val_len,
470 this_attr->address);
471 else
472 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
473 &vals[0], &vals[1], this_attr->address);
474
475 if (ret < 0)
476 return ret;
477
478 return iio_format_value(buf, ret, val_len, vals);
479 }
480
481 /**
482 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
483 * @str: The string to parse
484 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
485 * @integer: The integer part of the number
486 * @fract: The fractional part of the number
487 *
488 * Returns 0 on success, or a negative error code if the string could not be
489 * parsed.
490 */
491 int iio_str_to_fixpoint(const char *str, int fract_mult,
492 int *integer, int *fract)
493 {
494 int i = 0, f = 0;
495 bool integer_part = true, negative = false;
496
497 if (str[0] == '-') {
498 negative = true;
499 str++;
500 } else if (str[0] == '+') {
501 str++;
502 }
503
504 while (*str) {
505 if ('0' <= *str && *str <= '9') {
506 if (integer_part) {
507 i = i * 10 + *str - '0';
508 } else {
509 f += fract_mult * (*str - '0');
510 fract_mult /= 10;
511 }
512 } else if (*str == '\n') {
513 if (*(str + 1) == '\0')
514 break;
515 else
516 return -EINVAL;
517 } else if (*str == '.' && integer_part) {
518 integer_part = false;
519 } else {
520 return -EINVAL;
521 }
522 str++;
523 }
524
525 if (negative) {
526 if (i)
527 i = -i;
528 else
529 f = -f;
530 }
531
532 *integer = i;
533 *fract = f;
534
535 return 0;
536 }
537 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
538
539 static ssize_t iio_write_channel_info(struct device *dev,
540 struct device_attribute *attr,
541 const char *buf,
542 size_t len)
543 {
544 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
545 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
546 int ret, fract_mult = 100000;
547 int integer, fract;
548
549 /* Assumes decimal - precision based on number of digits */
550 if (!indio_dev->info->write_raw)
551 return -EINVAL;
552
553 if (indio_dev->info->write_raw_get_fmt)
554 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
555 this_attr->c, this_attr->address)) {
556 case IIO_VAL_INT_PLUS_MICRO:
557 fract_mult = 100000;
558 break;
559 case IIO_VAL_INT_PLUS_NANO:
560 fract_mult = 100000000;
561 break;
562 default:
563 return -EINVAL;
564 }
565
566 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
567 if (ret)
568 return ret;
569
570 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
571 integer, fract, this_attr->address);
572 if (ret)
573 return ret;
574
575 return len;
576 }
577
578 static
579 int __iio_device_attr_init(struct device_attribute *dev_attr,
580 const char *postfix,
581 struct iio_chan_spec const *chan,
582 ssize_t (*readfunc)(struct device *dev,
583 struct device_attribute *attr,
584 char *buf),
585 ssize_t (*writefunc)(struct device *dev,
586 struct device_attribute *attr,
587 const char *buf,
588 size_t len),
589 enum iio_shared_by shared_by)
590 {
591 int ret = 0;
592 char *name = NULL;
593 char *full_postfix;
594 sysfs_attr_init(&dev_attr->attr);
595
596 /* Build up postfix of <extend_name>_<modifier>_postfix */
597 if (chan->modified && (shared_by == IIO_SEPARATE)) {
598 if (chan->extend_name)
599 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
600 iio_modifier_names[chan
601 ->channel2],
602 chan->extend_name,
603 postfix);
604 else
605 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
606 iio_modifier_names[chan
607 ->channel2],
608 postfix);
609 } else {
610 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
611 full_postfix = kstrdup(postfix, GFP_KERNEL);
612 else
613 full_postfix = kasprintf(GFP_KERNEL,
614 "%s_%s",
615 chan->extend_name,
616 postfix);
617 }
618 if (full_postfix == NULL)
619 return -ENOMEM;
620
621 if (chan->differential) { /* Differential can not have modifier */
622 switch (shared_by) {
623 case IIO_SHARED_BY_ALL:
624 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
625 break;
626 case IIO_SHARED_BY_DIR:
627 name = kasprintf(GFP_KERNEL, "%s_%s",
628 iio_direction[chan->output],
629 full_postfix);
630 break;
631 case IIO_SHARED_BY_TYPE:
632 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
633 iio_direction[chan->output],
634 iio_chan_type_name_spec[chan->type],
635 iio_chan_type_name_spec[chan->type],
636 full_postfix);
637 break;
638 case IIO_SEPARATE:
639 if (!chan->indexed) {
640 WARN_ON("Differential channels must be indexed\n");
641 ret = -EINVAL;
642 goto error_free_full_postfix;
643 }
644 name = kasprintf(GFP_KERNEL,
645 "%s_%s%d-%s%d_%s",
646 iio_direction[chan->output],
647 iio_chan_type_name_spec[chan->type],
648 chan->channel,
649 iio_chan_type_name_spec[chan->type],
650 chan->channel2,
651 full_postfix);
652 break;
653 }
654 } else { /* Single ended */
655 switch (shared_by) {
656 case IIO_SHARED_BY_ALL:
657 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
658 break;
659 case IIO_SHARED_BY_DIR:
660 name = kasprintf(GFP_KERNEL, "%s_%s",
661 iio_direction[chan->output],
662 full_postfix);
663 break;
664 case IIO_SHARED_BY_TYPE:
665 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
666 iio_direction[chan->output],
667 iio_chan_type_name_spec[chan->type],
668 full_postfix);
669 break;
670
671 case IIO_SEPARATE:
672 if (chan->indexed)
673 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
674 iio_direction[chan->output],
675 iio_chan_type_name_spec[chan->type],
676 chan->channel,
677 full_postfix);
678 else
679 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
680 iio_direction[chan->output],
681 iio_chan_type_name_spec[chan->type],
682 full_postfix);
683 break;
684 }
685 }
686 if (name == NULL) {
687 ret = -ENOMEM;
688 goto error_free_full_postfix;
689 }
690 dev_attr->attr.name = name;
691
692 if (readfunc) {
693 dev_attr->attr.mode |= S_IRUGO;
694 dev_attr->show = readfunc;
695 }
696
697 if (writefunc) {
698 dev_attr->attr.mode |= S_IWUSR;
699 dev_attr->store = writefunc;
700 }
701
702 error_free_full_postfix:
703 kfree(full_postfix);
704
705 return ret;
706 }
707
708 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
709 {
710 kfree(dev_attr->attr.name);
711 }
712
713 int __iio_add_chan_devattr(const char *postfix,
714 struct iio_chan_spec const *chan,
715 ssize_t (*readfunc)(struct device *dev,
716 struct device_attribute *attr,
717 char *buf),
718 ssize_t (*writefunc)(struct device *dev,
719 struct device_attribute *attr,
720 const char *buf,
721 size_t len),
722 u64 mask,
723 enum iio_shared_by shared_by,
724 struct device *dev,
725 struct list_head *attr_list)
726 {
727 int ret;
728 struct iio_dev_attr *iio_attr, *t;
729
730 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
731 if (iio_attr == NULL)
732 return -ENOMEM;
733 ret = __iio_device_attr_init(&iio_attr->dev_attr,
734 postfix, chan,
735 readfunc, writefunc, shared_by);
736 if (ret)
737 goto error_iio_dev_attr_free;
738 iio_attr->c = chan;
739 iio_attr->address = mask;
740 list_for_each_entry(t, attr_list, l)
741 if (strcmp(t->dev_attr.attr.name,
742 iio_attr->dev_attr.attr.name) == 0) {
743 if (shared_by == IIO_SEPARATE)
744 dev_err(dev, "tried to double register : %s\n",
745 t->dev_attr.attr.name);
746 ret = -EBUSY;
747 goto error_device_attr_deinit;
748 }
749 list_add(&iio_attr->l, attr_list);
750
751 return 0;
752
753 error_device_attr_deinit:
754 __iio_device_attr_deinit(&iio_attr->dev_attr);
755 error_iio_dev_attr_free:
756 kfree(iio_attr);
757 return ret;
758 }
759
760 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
761 struct iio_chan_spec const *chan,
762 enum iio_shared_by shared_by,
763 const long *infomask)
764 {
765 int i, ret, attrcount = 0;
766
767 for_each_set_bit(i, infomask, sizeof(infomask)*8) {
768 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
769 return -EINVAL;
770 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
771 chan,
772 &iio_read_channel_info,
773 &iio_write_channel_info,
774 i,
775 shared_by,
776 &indio_dev->dev,
777 &indio_dev->channel_attr_list);
778 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
779 continue;
780 else if (ret < 0)
781 return ret;
782 attrcount++;
783 }
784
785 return attrcount;
786 }
787
788 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
789 struct iio_chan_spec const *chan)
790 {
791 int ret, attrcount = 0;
792 const struct iio_chan_spec_ext_info *ext_info;
793
794 if (chan->channel < 0)
795 return 0;
796 ret = iio_device_add_info_mask_type(indio_dev, chan,
797 IIO_SEPARATE,
798 &chan->info_mask_separate);
799 if (ret < 0)
800 return ret;
801 attrcount += ret;
802
803 ret = iio_device_add_info_mask_type(indio_dev, chan,
804 IIO_SHARED_BY_TYPE,
805 &chan->info_mask_shared_by_type);
806 if (ret < 0)
807 return ret;
808 attrcount += ret;
809
810 ret = iio_device_add_info_mask_type(indio_dev, chan,
811 IIO_SHARED_BY_DIR,
812 &chan->info_mask_shared_by_dir);
813 if (ret < 0)
814 return ret;
815 attrcount += ret;
816
817 ret = iio_device_add_info_mask_type(indio_dev, chan,
818 IIO_SHARED_BY_ALL,
819 &chan->info_mask_shared_by_all);
820 if (ret < 0)
821 return ret;
822 attrcount += ret;
823
824 if (chan->ext_info) {
825 unsigned int i = 0;
826 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
827 ret = __iio_add_chan_devattr(ext_info->name,
828 chan,
829 ext_info->read ?
830 &iio_read_channel_ext_info : NULL,
831 ext_info->write ?
832 &iio_write_channel_ext_info : NULL,
833 i,
834 ext_info->shared,
835 &indio_dev->dev,
836 &indio_dev->channel_attr_list);
837 i++;
838 if (ret == -EBUSY && ext_info->shared)
839 continue;
840
841 if (ret)
842 return ret;
843
844 attrcount++;
845 }
846 }
847
848 return attrcount;
849 }
850
851 /**
852 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
853 * @attr_list: List of IIO device attributes
854 *
855 * This function frees the memory allocated for each of the IIO device
856 * attributes in the list.
857 */
858 void iio_free_chan_devattr_list(struct list_head *attr_list)
859 {
860 struct iio_dev_attr *p, *n;
861
862 list_for_each_entry_safe(p, n, attr_list, l) {
863 kfree(p->dev_attr.attr.name);
864 list_del(&p->l);
865 kfree(p);
866 }
867 }
868
869 static ssize_t iio_show_dev_name(struct device *dev,
870 struct device_attribute *attr,
871 char *buf)
872 {
873 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
874 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
875 }
876
877 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
878
879 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
880 {
881 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
882 struct iio_dev_attr *p;
883 struct attribute **attr;
884
885 /* First count elements in any existing group */
886 if (indio_dev->info->attrs) {
887 attr = indio_dev->info->attrs->attrs;
888 while (*attr++ != NULL)
889 attrcount_orig++;
890 }
891 attrcount = attrcount_orig;
892 /*
893 * New channel registration method - relies on the fact a group does
894 * not need to be initialized if its name is NULL.
895 */
896 if (indio_dev->channels)
897 for (i = 0; i < indio_dev->num_channels; i++) {
898 ret = iio_device_add_channel_sysfs(indio_dev,
899 &indio_dev
900 ->channels[i]);
901 if (ret < 0)
902 goto error_clear_attrs;
903 attrcount += ret;
904 }
905
906 if (indio_dev->name)
907 attrcount++;
908
909 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
910 sizeof(indio_dev->chan_attr_group.attrs[0]),
911 GFP_KERNEL);
912 if (indio_dev->chan_attr_group.attrs == NULL) {
913 ret = -ENOMEM;
914 goto error_clear_attrs;
915 }
916 /* Copy across original attributes */
917 if (indio_dev->info->attrs)
918 memcpy(indio_dev->chan_attr_group.attrs,
919 indio_dev->info->attrs->attrs,
920 sizeof(indio_dev->chan_attr_group.attrs[0])
921 *attrcount_orig);
922 attrn = attrcount_orig;
923 /* Add all elements from the list. */
924 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
925 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
926 if (indio_dev->name)
927 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
928
929 indio_dev->groups[indio_dev->groupcounter++] =
930 &indio_dev->chan_attr_group;
931
932 return 0;
933
934 error_clear_attrs:
935 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
936
937 return ret;
938 }
939
940 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
941 {
942
943 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
944 kfree(indio_dev->chan_attr_group.attrs);
945 indio_dev->chan_attr_group.attrs = NULL;
946 }
947
948 static void iio_dev_release(struct device *device)
949 {
950 struct iio_dev *indio_dev = dev_to_iio_dev(device);
951 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
952 iio_device_unregister_trigger_consumer(indio_dev);
953 iio_device_unregister_eventset(indio_dev);
954 iio_device_unregister_sysfs(indio_dev);
955
956 iio_buffer_put(indio_dev->buffer);
957
958 ida_simple_remove(&iio_ida, indio_dev->id);
959 kfree(indio_dev);
960 }
961
962 struct device_type iio_device_type = {
963 .name = "iio_device",
964 .release = iio_dev_release,
965 };
966
967 /**
968 * iio_device_alloc() - allocate an iio_dev from a driver
969 * @sizeof_priv: Space to allocate for private structure.
970 **/
971 struct iio_dev *iio_device_alloc(int sizeof_priv)
972 {
973 struct iio_dev *dev;
974 size_t alloc_size;
975
976 alloc_size = sizeof(struct iio_dev);
977 if (sizeof_priv) {
978 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
979 alloc_size += sizeof_priv;
980 }
981 /* ensure 32-byte alignment of whole construct ? */
982 alloc_size += IIO_ALIGN - 1;
983
984 dev = kzalloc(alloc_size, GFP_KERNEL);
985
986 if (dev) {
987 dev->dev.groups = dev->groups;
988 dev->dev.type = &iio_device_type;
989 dev->dev.bus = &iio_bus_type;
990 device_initialize(&dev->dev);
991 dev_set_drvdata(&dev->dev, (void *)dev);
992 mutex_init(&dev->mlock);
993 mutex_init(&dev->info_exist_lock);
994 INIT_LIST_HEAD(&dev->channel_attr_list);
995
996 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
997 if (dev->id < 0) {
998 /* cannot use a dev_err as the name isn't available */
999 pr_err("failed to get device id\n");
1000 kfree(dev);
1001 return NULL;
1002 }
1003 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1004 INIT_LIST_HEAD(&dev->buffer_list);
1005 }
1006
1007 return dev;
1008 }
1009 EXPORT_SYMBOL(iio_device_alloc);
1010
1011 /**
1012 * iio_device_free() - free an iio_dev from a driver
1013 * @dev: the iio_dev associated with the device
1014 **/
1015 void iio_device_free(struct iio_dev *dev)
1016 {
1017 if (dev)
1018 put_device(&dev->dev);
1019 }
1020 EXPORT_SYMBOL(iio_device_free);
1021
1022 static void devm_iio_device_release(struct device *dev, void *res)
1023 {
1024 iio_device_free(*(struct iio_dev **)res);
1025 }
1026
1027 static int devm_iio_device_match(struct device *dev, void *res, void *data)
1028 {
1029 struct iio_dev **r = res;
1030 if (!r || !*r) {
1031 WARN_ON(!r || !*r);
1032 return 0;
1033 }
1034 return *r == data;
1035 }
1036
1037 /**
1038 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1039 * @dev: Device to allocate iio_dev for
1040 * @sizeof_priv: Space to allocate for private structure.
1041 *
1042 * Managed iio_device_alloc. iio_dev allocated with this function is
1043 * automatically freed on driver detach.
1044 *
1045 * If an iio_dev allocated with this function needs to be freed separately,
1046 * devm_iio_device_free() must be used.
1047 *
1048 * RETURNS:
1049 * Pointer to allocated iio_dev on success, NULL on failure.
1050 */
1051 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1052 {
1053 struct iio_dev **ptr, *iio_dev;
1054
1055 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1056 GFP_KERNEL);
1057 if (!ptr)
1058 return NULL;
1059
1060 iio_dev = iio_device_alloc(sizeof_priv);
1061 if (iio_dev) {
1062 *ptr = iio_dev;
1063 devres_add(dev, ptr);
1064 } else {
1065 devres_free(ptr);
1066 }
1067
1068 return iio_dev;
1069 }
1070 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1071
1072 /**
1073 * devm_iio_device_free - Resource-managed iio_device_free()
1074 * @dev: Device this iio_dev belongs to
1075 * @iio_dev: the iio_dev associated with the device
1076 *
1077 * Free iio_dev allocated with devm_iio_device_alloc().
1078 */
1079 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1080 {
1081 int rc;
1082
1083 rc = devres_release(dev, devm_iio_device_release,
1084 devm_iio_device_match, iio_dev);
1085 WARN_ON(rc);
1086 }
1087 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1088
1089 /**
1090 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1091 **/
1092 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1093 {
1094 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1095 struct iio_dev, chrdev);
1096
1097 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1098 return -EBUSY;
1099
1100 iio_device_get(indio_dev);
1101
1102 filp->private_data = indio_dev;
1103
1104 return 0;
1105 }
1106
1107 /**
1108 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1109 **/
1110 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1111 {
1112 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1113 struct iio_dev, chrdev);
1114 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1115 iio_device_put(indio_dev);
1116
1117 return 0;
1118 }
1119
1120 /* Somewhat of a cross file organization violation - ioctls here are actually
1121 * event related */
1122 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1123 {
1124 struct iio_dev *indio_dev = filp->private_data;
1125 int __user *ip = (int __user *)arg;
1126 int fd;
1127
1128 if (!indio_dev->info)
1129 return -ENODEV;
1130
1131 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1132 fd = iio_event_getfd(indio_dev);
1133 if (copy_to_user(ip, &fd, sizeof(fd)))
1134 return -EFAULT;
1135 return 0;
1136 }
1137 return -EINVAL;
1138 }
1139
1140 static const struct file_operations iio_buffer_fileops = {
1141 .read = iio_buffer_read_first_n_outer_addr,
1142 .release = iio_chrdev_release,
1143 .open = iio_chrdev_open,
1144 .poll = iio_buffer_poll_addr,
1145 .owner = THIS_MODULE,
1146 .llseek = noop_llseek,
1147 .unlocked_ioctl = iio_ioctl,
1148 .compat_ioctl = iio_ioctl,
1149 };
1150
1151 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1152 {
1153 int i, j;
1154 const struct iio_chan_spec *channels = indio_dev->channels;
1155
1156 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1157 return 0;
1158
1159 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1160 if (channels[i].scan_index < 0)
1161 continue;
1162 for (j = i + 1; j < indio_dev->num_channels; j++)
1163 if (channels[i].scan_index == channels[j].scan_index) {
1164 dev_err(&indio_dev->dev,
1165 "Duplicate scan index %d\n",
1166 channels[i].scan_index);
1167 return -EINVAL;
1168 }
1169 }
1170
1171 return 0;
1172 }
1173
1174 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1175
1176 /**
1177 * iio_device_register() - register a device with the IIO subsystem
1178 * @indio_dev: Device structure filled by the device driver
1179 **/
1180 int iio_device_register(struct iio_dev *indio_dev)
1181 {
1182 int ret;
1183
1184 /* If the calling driver did not initialize of_node, do it here */
1185 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1186 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1187
1188 ret = iio_check_unique_scan_index(indio_dev);
1189 if (ret < 0)
1190 return ret;
1191
1192 /* configure elements for the chrdev */
1193 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1194
1195 ret = iio_device_register_debugfs(indio_dev);
1196 if (ret) {
1197 dev_err(indio_dev->dev.parent,
1198 "Failed to register debugfs interfaces\n");
1199 return ret;
1200 }
1201
1202 ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1203 if (ret) {
1204 dev_err(indio_dev->dev.parent,
1205 "Failed to create buffer sysfs interfaces\n");
1206 goto error_unreg_debugfs;
1207 }
1208
1209 ret = iio_device_register_sysfs(indio_dev);
1210 if (ret) {
1211 dev_err(indio_dev->dev.parent,
1212 "Failed to register sysfs interfaces\n");
1213 goto error_buffer_free_sysfs;
1214 }
1215 ret = iio_device_register_eventset(indio_dev);
1216 if (ret) {
1217 dev_err(indio_dev->dev.parent,
1218 "Failed to register event set\n");
1219 goto error_free_sysfs;
1220 }
1221 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
1222 iio_device_register_trigger_consumer(indio_dev);
1223
1224 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1225 indio_dev->setup_ops == NULL)
1226 indio_dev->setup_ops = &noop_ring_setup_ops;
1227
1228 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1229 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1230 indio_dev->chrdev.kobj.parent = &indio_dev->dev.kobj;
1231 ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
1232 if (ret < 0)
1233 goto error_unreg_eventset;
1234
1235 ret = device_add(&indio_dev->dev);
1236 if (ret < 0)
1237 goto error_cdev_del;
1238
1239 return 0;
1240 error_cdev_del:
1241 cdev_del(&indio_dev->chrdev);
1242 error_unreg_eventset:
1243 iio_device_unregister_eventset(indio_dev);
1244 error_free_sysfs:
1245 iio_device_unregister_sysfs(indio_dev);
1246 error_buffer_free_sysfs:
1247 iio_buffer_free_sysfs_and_mask(indio_dev);
1248 error_unreg_debugfs:
1249 iio_device_unregister_debugfs(indio_dev);
1250 return ret;
1251 }
1252 EXPORT_SYMBOL(iio_device_register);
1253
1254 /**
1255 * iio_device_unregister() - unregister a device from the IIO subsystem
1256 * @indio_dev: Device structure representing the device.
1257 **/
1258 void iio_device_unregister(struct iio_dev *indio_dev)
1259 {
1260 mutex_lock(&indio_dev->info_exist_lock);
1261
1262 device_del(&indio_dev->dev);
1263
1264 if (indio_dev->chrdev.dev)
1265 cdev_del(&indio_dev->chrdev);
1266 iio_device_unregister_debugfs(indio_dev);
1267
1268 iio_disable_all_buffers(indio_dev);
1269
1270 indio_dev->info = NULL;
1271
1272 iio_device_wakeup_eventset(indio_dev);
1273 iio_buffer_wakeup_poll(indio_dev);
1274
1275 mutex_unlock(&indio_dev->info_exist_lock);
1276
1277 iio_buffer_free_sysfs_and_mask(indio_dev);
1278 }
1279 EXPORT_SYMBOL(iio_device_unregister);
1280
1281 static void devm_iio_device_unreg(struct device *dev, void *res)
1282 {
1283 iio_device_unregister(*(struct iio_dev **)res);
1284 }
1285
1286 /**
1287 * devm_iio_device_register - Resource-managed iio_device_register()
1288 * @dev: Device to allocate iio_dev for
1289 * @indio_dev: Device structure filled by the device driver
1290 *
1291 * Managed iio_device_register. The IIO device registered with this
1292 * function is automatically unregistered on driver detach. This function
1293 * calls iio_device_register() internally. Refer to that function for more
1294 * information.
1295 *
1296 * If an iio_dev registered with this function needs to be unregistered
1297 * separately, devm_iio_device_unregister() must be used.
1298 *
1299 * RETURNS:
1300 * 0 on success, negative error number on failure.
1301 */
1302 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev)
1303 {
1304 struct iio_dev **ptr;
1305 int ret;
1306
1307 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1308 if (!ptr)
1309 return -ENOMEM;
1310
1311 *ptr = indio_dev;
1312 ret = iio_device_register(indio_dev);
1313 if (!ret)
1314 devres_add(dev, ptr);
1315 else
1316 devres_free(ptr);
1317
1318 return ret;
1319 }
1320 EXPORT_SYMBOL_GPL(devm_iio_device_register);
1321
1322 /**
1323 * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1324 * @dev: Device this iio_dev belongs to
1325 * @indio_dev: the iio_dev associated with the device
1326 *
1327 * Unregister iio_dev registered with devm_iio_device_register().
1328 */
1329 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1330 {
1331 int rc;
1332
1333 rc = devres_release(dev, devm_iio_device_unreg,
1334 devm_iio_device_match, indio_dev);
1335 WARN_ON(rc);
1336 }
1337 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1338
1339 subsys_initcall(iio_init);
1340 module_exit(iio_exit);
1341
1342 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1343 MODULE_DESCRIPTION("Industrial I/O core");
1344 MODULE_LICENSE("GPL");
Linux with added FPC-III support