Merge tag 'v3.10.82' into update
[GitHub/mt8127/android_kernel_alcatel_ttab.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 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/idr.h>
15 #include <linux/kdev_t.h>
16 #include <linux/err.h>
17 #include <linux/device.h>
18 #include <linux/fs.h>
19 #include <linux/poll.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/iio/iio.h>
27 #include "iio_core.h"
28 #include "iio_core_trigger.h"
29 #include <linux/iio/sysfs.h>
30 #include <linux/iio/events.h>
31
32 /* IDA to assign each registered device a unique id */
33 static DEFINE_IDA(iio_ida);
34
35 static dev_t iio_devt;
36
37 #define IIO_DEV_MAX 256
38 struct bus_type iio_bus_type = {
39 .name = "iio",
40 };
41 EXPORT_SYMBOL(iio_bus_type);
42
43 static struct dentry *iio_debugfs_dentry;
44
45 static const char * const iio_direction[] = {
46 [0] = "in",
47 [1] = "out",
48 };
49
50 static const char * const iio_chan_type_name_spec[] = {
51 [IIO_VOLTAGE] = "voltage",
52 [IIO_CURRENT] = "current",
53 [IIO_POWER] = "power",
54 [IIO_ACCEL] = "accel",
55 [IIO_ANGL_VEL] = "anglvel",
56 [IIO_MAGN] = "magn",
57 [IIO_LIGHT] = "illuminance",
58 [IIO_INTENSITY] = "intensity",
59 [IIO_PROXIMITY] = "proximity",
60 [IIO_TEMP] = "temp",
61 [IIO_INCLI] = "incli",
62 [IIO_ROT] = "rot",
63 [IIO_ANGL] = "angl",
64 [IIO_TIMESTAMP] = "timestamp",
65 [IIO_CAPACITANCE] = "capacitance",
66 [IIO_ALTVOLTAGE] = "altvoltage",
67 [IIO_CCT] = "cct",
68 [IIO_PRESSURE] = "pressure",
69 };
70
71 static const char * const iio_modifier_names[] = {
72 [IIO_MOD_X] = "x",
73 [IIO_MOD_Y] = "y",
74 [IIO_MOD_Z] = "z",
75 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
76 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
77 [IIO_MOD_LIGHT_BOTH] = "both",
78 [IIO_MOD_LIGHT_IR] = "ir",
79 [IIO_MOD_LIGHT_CLEAR] = "clear",
80 [IIO_MOD_LIGHT_RED] = "red",
81 [IIO_MOD_LIGHT_GREEN] = "green",
82 [IIO_MOD_LIGHT_BLUE] = "blue",
83 };
84
85 /* relies on pairs of these shared then separate */
86 static const char * const iio_chan_info_postfix[] = {
87 [IIO_CHAN_INFO_RAW] = "raw",
88 [IIO_CHAN_INFO_PROCESSED] = "input",
89 [IIO_CHAN_INFO_SCALE] = "scale",
90 [IIO_CHAN_INFO_OFFSET] = "offset",
91 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
92 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
93 [IIO_CHAN_INFO_PEAK] = "peak_raw",
94 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
95 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
96 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
97 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
98 = "filter_low_pass_3db_frequency",
99 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
100 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
101 [IIO_CHAN_INFO_PHASE] = "phase",
102 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
103 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
104 };
105
106 const struct iio_chan_spec
107 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
108 {
109 int i;
110
111 for (i = 0; i < indio_dev->num_channels; i++)
112 if (indio_dev->channels[i].scan_index == si)
113 return &indio_dev->channels[i];
114 return NULL;
115 }
116
117 /* This turns up an awful lot */
118 ssize_t iio_read_const_attr(struct device *dev,
119 struct device_attribute *attr,
120 char *buf)
121 {
122 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
123 }
124 EXPORT_SYMBOL(iio_read_const_attr);
125
126 static int __init iio_init(void)
127 {
128 int ret;
129
130 /* Register sysfs bus */
131 ret = bus_register(&iio_bus_type);
132 if (ret < 0) {
133 printk(KERN_ERR
134 "%s could not register bus type\n",
135 __FILE__);
136 goto error_nothing;
137 }
138
139 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
140 if (ret < 0) {
141 printk(KERN_ERR "%s: failed to allocate char dev region\n",
142 __FILE__);
143 goto error_unregister_bus_type;
144 }
145
146 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
147
148 return 0;
149
150 error_unregister_bus_type:
151 bus_unregister(&iio_bus_type);
152 error_nothing:
153 return ret;
154 }
155
156 static void __exit iio_exit(void)
157 {
158 if (iio_devt)
159 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
160 bus_unregister(&iio_bus_type);
161 debugfs_remove(iio_debugfs_dentry);
162 }
163
164 #if defined(CONFIG_DEBUG_FS)
165 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
166 size_t count, loff_t *ppos)
167 {
168 struct iio_dev *indio_dev = file->private_data;
169 char buf[20];
170 unsigned val = 0;
171 ssize_t len;
172 int ret;
173
174 ret = indio_dev->info->debugfs_reg_access(indio_dev,
175 indio_dev->cached_reg_addr,
176 0, &val);
177 if (ret)
178 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
179
180 len = snprintf(buf, sizeof(buf), "0x%X\n", val);
181
182 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
183 }
184
185 static ssize_t iio_debugfs_write_reg(struct file *file,
186 const char __user *userbuf, size_t count, loff_t *ppos)
187 {
188 struct iio_dev *indio_dev = file->private_data;
189 unsigned reg, val;
190 char buf[80];
191 int ret;
192
193 count = min_t(size_t, count, (sizeof(buf)-1));
194 if (copy_from_user(buf, userbuf, count))
195 return -EFAULT;
196
197 buf[count] = 0;
198
199 ret = sscanf(buf, "%i %i", &reg, &val);
200
201 switch (ret) {
202 case 1:
203 indio_dev->cached_reg_addr = reg;
204 break;
205 case 2:
206 indio_dev->cached_reg_addr = reg;
207 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
208 val, NULL);
209 if (ret) {
210 dev_err(indio_dev->dev.parent, "%s: write failed\n",
211 __func__);
212 return ret;
213 }
214 break;
215 default:
216 return -EINVAL;
217 }
218
219 return count;
220 }
221
222 static const struct file_operations iio_debugfs_reg_fops = {
223 .open = simple_open,
224 .read = iio_debugfs_read_reg,
225 .write = iio_debugfs_write_reg,
226 };
227
228 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
229 {
230 debugfs_remove_recursive(indio_dev->debugfs_dentry);
231 }
232
233 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
234 {
235 struct dentry *d;
236
237 if (indio_dev->info->debugfs_reg_access == NULL)
238 return 0;
239
240 if (!iio_debugfs_dentry)
241 return 0;
242
243 indio_dev->debugfs_dentry =
244 debugfs_create_dir(dev_name(&indio_dev->dev),
245 iio_debugfs_dentry);
246 if (indio_dev->debugfs_dentry == NULL) {
247 dev_warn(indio_dev->dev.parent,
248 "Failed to create debugfs directory\n");
249 return -EFAULT;
250 }
251
252 d = debugfs_create_file("direct_reg_access", 0644,
253 indio_dev->debugfs_dentry,
254 indio_dev, &iio_debugfs_reg_fops);
255 if (!d) {
256 iio_device_unregister_debugfs(indio_dev);
257 return -ENOMEM;
258 }
259
260 return 0;
261 }
262 #else
263 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
264 {
265 return 0;
266 }
267
268 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
269 {
270 }
271 #endif /* CONFIG_DEBUG_FS */
272
273 static ssize_t iio_read_channel_ext_info(struct device *dev,
274 struct device_attribute *attr,
275 char *buf)
276 {
277 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
278 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
279 const struct iio_chan_spec_ext_info *ext_info;
280
281 ext_info = &this_attr->c->ext_info[this_attr->address];
282
283 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
284 }
285
286 static ssize_t iio_write_channel_ext_info(struct device *dev,
287 struct device_attribute *attr,
288 const char *buf,
289 size_t len)
290 {
291 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
292 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
293 const struct iio_chan_spec_ext_info *ext_info;
294
295 ext_info = &this_attr->c->ext_info[this_attr->address];
296
297 return ext_info->write(indio_dev, ext_info->private,
298 this_attr->c, buf, len);
299 }
300
301 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
302 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
303 {
304 const struct iio_enum *e = (const struct iio_enum *)priv;
305 unsigned int i;
306 size_t len = 0;
307
308 if (!e->num_items)
309 return 0;
310
311 for (i = 0; i < e->num_items; ++i)
312 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
313
314 /* replace last space with a newline */
315 buf[len - 1] = '\n';
316
317 return len;
318 }
319 EXPORT_SYMBOL_GPL(iio_enum_available_read);
320
321 ssize_t iio_enum_read(struct iio_dev *indio_dev,
322 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
323 {
324 const struct iio_enum *e = (const struct iio_enum *)priv;
325 int i;
326
327 if (!e->get)
328 return -EINVAL;
329
330 i = e->get(indio_dev, chan);
331 if (i < 0)
332 return i;
333 else if (i >= e->num_items)
334 return -EINVAL;
335
336 return sprintf(buf, "%s\n", e->items[i]);
337 }
338 EXPORT_SYMBOL_GPL(iio_enum_read);
339
340 ssize_t iio_enum_write(struct iio_dev *indio_dev,
341 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
342 size_t len)
343 {
344 const struct iio_enum *e = (const struct iio_enum *)priv;
345 unsigned int i;
346 int ret;
347
348 if (!e->set)
349 return -EINVAL;
350
351 for (i = 0; i < e->num_items; i++) {
352 if (sysfs_streq(buf, e->items[i]))
353 break;
354 }
355
356 if (i == e->num_items)
357 return -EINVAL;
358
359 ret = e->set(indio_dev, chan, i);
360 return ret ? ret : len;
361 }
362 EXPORT_SYMBOL_GPL(iio_enum_write);
363
364 static ssize_t iio_read_channel_info(struct device *dev,
365 struct device_attribute *attr,
366 char *buf)
367 {
368 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
369 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
370 unsigned long long tmp;
371 int val, val2;
372 bool scale_db = false;
373 int ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
374 &val, &val2, this_attr->address);
375
376 if (ret < 0)
377 return ret;
378
379 switch (ret) {
380 case IIO_VAL_INT:
381 return sprintf(buf, "%d\n", val);
382 case IIO_VAL_INT_PLUS_MICRO_DB:
383 scale_db = true;
384 case IIO_VAL_INT_PLUS_MICRO:
385 if (val2 < 0)
386 return sprintf(buf, "-%d.%06u%s\n", val, -val2,
387 scale_db ? " dB" : "");
388 else
389 return sprintf(buf, "%d.%06u%s\n", val, val2,
390 scale_db ? " dB" : "");
391 case IIO_VAL_INT_PLUS_NANO:
392 if (val2 < 0)
393 return sprintf(buf, "-%d.%09u\n", val, -val2);
394 else
395 return sprintf(buf, "%d.%09u\n", val, val2);
396 case IIO_VAL_FRACTIONAL:
397 tmp = div_s64((s64)val * 1000000000LL, val2);
398 val2 = do_div(tmp, 1000000000LL);
399 val = tmp;
400 return sprintf(buf, "%d.%09u\n", val, val2);
401 case IIO_VAL_FRACTIONAL_LOG2:
402 tmp = (s64)val * 1000000000LL >> val2;
403 val2 = do_div(tmp, 1000000000LL);
404 val = tmp;
405 return sprintf(buf, "%d.%09u\n", val, val2);
406 default:
407 return 0;
408 }
409 }
410
411 /**
412 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
413 * @str: The string to parse
414 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
415 * @integer: The integer part of the number
416 * @fract: The fractional part of the number
417 *
418 * Returns 0 on success, or a negative error code if the string could not be
419 * parsed.
420 */
421 int iio_str_to_fixpoint(const char *str, int fract_mult,
422 int *integer, int *fract)
423 {
424 int i = 0, f = 0;
425 bool integer_part = true, negative = false;
426
427 if (str[0] == '-') {
428 negative = true;
429 str++;
430 } else if (str[0] == '+') {
431 str++;
432 }
433
434 while (*str) {
435 if ('0' <= *str && *str <= '9') {
436 if (integer_part) {
437 i = i * 10 + *str - '0';
438 } else {
439 f += fract_mult * (*str - '0');
440 fract_mult /= 10;
441 }
442 } else if (*str == '\n') {
443 if (*(str + 1) == '\0')
444 break;
445 else
446 return -EINVAL;
447 } else if (*str == '.' && integer_part) {
448 integer_part = false;
449 } else {
450 return -EINVAL;
451 }
452 str++;
453 }
454
455 if (negative) {
456 if (i)
457 i = -i;
458 else
459 f = -f;
460 }
461
462 *integer = i;
463 *fract = f;
464
465 return 0;
466 }
467 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
468
469 static ssize_t iio_write_channel_info(struct device *dev,
470 struct device_attribute *attr,
471 const char *buf,
472 size_t len)
473 {
474 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
475 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
476 int ret, fract_mult = 100000;
477 int integer, fract;
478
479 /* Assumes decimal - precision based on number of digits */
480 if (!indio_dev->info->write_raw)
481 return -EINVAL;
482
483 if (indio_dev->info->write_raw_get_fmt)
484 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
485 this_attr->c, this_attr->address)) {
486 case IIO_VAL_INT_PLUS_MICRO:
487 fract_mult = 100000;
488 break;
489 case IIO_VAL_INT_PLUS_NANO:
490 fract_mult = 100000000;
491 break;
492 default:
493 return -EINVAL;
494 }
495
496 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
497 if (ret)
498 return ret;
499
500 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
501 integer, fract, this_attr->address);
502 if (ret)
503 return ret;
504
505 return len;
506 }
507
508 static
509 int __iio_device_attr_init(struct device_attribute *dev_attr,
510 const char *postfix,
511 struct iio_chan_spec const *chan,
512 ssize_t (*readfunc)(struct device *dev,
513 struct device_attribute *attr,
514 char *buf),
515 ssize_t (*writefunc)(struct device *dev,
516 struct device_attribute *attr,
517 const char *buf,
518 size_t len),
519 bool generic)
520 {
521 int ret;
522 char *name_format, *full_postfix;
523 sysfs_attr_init(&dev_attr->attr);
524
525 /* Build up postfix of <extend_name>_<modifier>_postfix */
526 if (chan->modified && !generic) {
527 if (chan->extend_name)
528 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
529 iio_modifier_names[chan
530 ->channel2],
531 chan->extend_name,
532 postfix);
533 else
534 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
535 iio_modifier_names[chan
536 ->channel2],
537 postfix);
538 } else {
539 if (chan->extend_name == NULL)
540 full_postfix = kstrdup(postfix, GFP_KERNEL);
541 else
542 full_postfix = kasprintf(GFP_KERNEL,
543 "%s_%s",
544 chan->extend_name,
545 postfix);
546 }
547 if (full_postfix == NULL) {
548 ret = -ENOMEM;
549 goto error_ret;
550 }
551
552 if (chan->differential) { /* Differential can not have modifier */
553 if (generic)
554 name_format
555 = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
556 iio_direction[chan->output],
557 iio_chan_type_name_spec[chan->type],
558 iio_chan_type_name_spec[chan->type],
559 full_postfix);
560 else if (chan->indexed)
561 name_format
562 = kasprintf(GFP_KERNEL, "%s_%s%d-%s%d_%s",
563 iio_direction[chan->output],
564 iio_chan_type_name_spec[chan->type],
565 chan->channel,
566 iio_chan_type_name_spec[chan->type],
567 chan->channel2,
568 full_postfix);
569 else {
570 WARN_ON("Differential channels must be indexed\n");
571 ret = -EINVAL;
572 goto error_free_full_postfix;
573 }
574 } else { /* Single ended */
575 if (generic)
576 name_format
577 = kasprintf(GFP_KERNEL, "%s_%s_%s",
578 iio_direction[chan->output],
579 iio_chan_type_name_spec[chan->type],
580 full_postfix);
581 else if (chan->indexed)
582 name_format
583 = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
584 iio_direction[chan->output],
585 iio_chan_type_name_spec[chan->type],
586 chan->channel,
587 full_postfix);
588 else
589 name_format
590 = kasprintf(GFP_KERNEL, "%s_%s_%s",
591 iio_direction[chan->output],
592 iio_chan_type_name_spec[chan->type],
593 full_postfix);
594 }
595 if (name_format == NULL) {
596 ret = -ENOMEM;
597 goto error_free_full_postfix;
598 }
599 dev_attr->attr.name = kasprintf(GFP_KERNEL,
600 name_format,
601 chan->channel,
602 chan->channel2);
603 if (dev_attr->attr.name == NULL) {
604 ret = -ENOMEM;
605 goto error_free_name_format;
606 }
607
608 if (readfunc) {
609 dev_attr->attr.mode |= S_IRUGO;
610 dev_attr->show = readfunc;
611 }
612
613 if (writefunc) {
614 dev_attr->attr.mode |= S_IWUSR;
615 dev_attr->store = writefunc;
616 }
617 kfree(name_format);
618 kfree(full_postfix);
619
620 return 0;
621
622 error_free_name_format:
623 kfree(name_format);
624 error_free_full_postfix:
625 kfree(full_postfix);
626 error_ret:
627 return ret;
628 }
629
630 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
631 {
632 kfree(dev_attr->attr.name);
633 }
634
635 int __iio_add_chan_devattr(const char *postfix,
636 struct iio_chan_spec const *chan,
637 ssize_t (*readfunc)(struct device *dev,
638 struct device_attribute *attr,
639 char *buf),
640 ssize_t (*writefunc)(struct device *dev,
641 struct device_attribute *attr,
642 const char *buf,
643 size_t len),
644 u64 mask,
645 bool generic,
646 struct device *dev,
647 struct list_head *attr_list)
648 {
649 int ret;
650 struct iio_dev_attr *iio_attr, *t;
651
652 iio_attr = kzalloc(sizeof *iio_attr, GFP_KERNEL);
653 if (iio_attr == NULL) {
654 ret = -ENOMEM;
655 goto error_ret;
656 }
657 ret = __iio_device_attr_init(&iio_attr->dev_attr,
658 postfix, chan,
659 readfunc, writefunc, generic);
660 if (ret)
661 goto error_iio_dev_attr_free;
662 iio_attr->c = chan;
663 iio_attr->address = mask;
664 list_for_each_entry(t, attr_list, l)
665 if (strcmp(t->dev_attr.attr.name,
666 iio_attr->dev_attr.attr.name) == 0) {
667 if (!generic)
668 dev_err(dev, "tried to double register : %s\n",
669 t->dev_attr.attr.name);
670 ret = -EBUSY;
671 goto error_device_attr_deinit;
672 }
673 list_add(&iio_attr->l, attr_list);
674
675 return 0;
676
677 error_device_attr_deinit:
678 __iio_device_attr_deinit(&iio_attr->dev_attr);
679 error_iio_dev_attr_free:
680 kfree(iio_attr);
681 error_ret:
682 return ret;
683 }
684
685 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
686 struct iio_chan_spec const *chan)
687 {
688 int ret, attrcount = 0;
689 int i;
690 const struct iio_chan_spec_ext_info *ext_info;
691
692 if (chan->channel < 0)
693 return 0;
694 for_each_set_bit(i, &chan->info_mask_separate, sizeof(long)*8) {
695 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
696 chan,
697 &iio_read_channel_info,
698 &iio_write_channel_info,
699 i,
700 0,
701 &indio_dev->dev,
702 &indio_dev->channel_attr_list);
703 if (ret < 0)
704 goto error_ret;
705 attrcount++;
706 }
707 for_each_set_bit(i, &chan->info_mask_shared_by_type, sizeof(long)*8) {
708 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
709 chan,
710 &iio_read_channel_info,
711 &iio_write_channel_info,
712 i,
713 1,
714 &indio_dev->dev,
715 &indio_dev->channel_attr_list);
716 if (ret == -EBUSY) {
717 ret = 0;
718 continue;
719 } else if (ret < 0) {
720 goto error_ret;
721 }
722 attrcount++;
723 }
724
725 if (chan->ext_info) {
726 unsigned int i = 0;
727 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
728 ret = __iio_add_chan_devattr(ext_info->name,
729 chan,
730 ext_info->read ?
731 &iio_read_channel_ext_info : NULL,
732 ext_info->write ?
733 &iio_write_channel_ext_info : NULL,
734 i,
735 ext_info->shared,
736 &indio_dev->dev,
737 &indio_dev->channel_attr_list);
738 i++;
739 if (ret == -EBUSY && ext_info->shared)
740 continue;
741
742 if (ret)
743 goto error_ret;
744
745 attrcount++;
746 }
747 }
748
749 ret = attrcount;
750 error_ret:
751 return ret;
752 }
753
754 static void iio_device_remove_and_free_read_attr(struct iio_dev *indio_dev,
755 struct iio_dev_attr *p)
756 {
757 kfree(p->dev_attr.attr.name);
758 kfree(p);
759 }
760
761 static ssize_t iio_show_dev_name(struct device *dev,
762 struct device_attribute *attr,
763 char *buf)
764 {
765 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
766 return sprintf(buf, "%s\n", indio_dev->name);
767 }
768
769 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
770
771 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
772 {
773 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
774 struct iio_dev_attr *p, *n;
775 struct attribute **attr;
776
777 /* First count elements in any existing group */
778 if (indio_dev->info->attrs) {
779 attr = indio_dev->info->attrs->attrs;
780 while (*attr++ != NULL)
781 attrcount_orig++;
782 }
783 attrcount = attrcount_orig;
784 /*
785 * New channel registration method - relies on the fact a group does
786 * not need to be initialized if its name is NULL.
787 */
788 if (indio_dev->channels)
789 for (i = 0; i < indio_dev->num_channels; i++) {
790 ret = iio_device_add_channel_sysfs(indio_dev,
791 &indio_dev
792 ->channels[i]);
793 if (ret < 0)
794 goto error_clear_attrs;
795 attrcount += ret;
796 }
797
798 if (indio_dev->name)
799 attrcount++;
800
801 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
802 sizeof(indio_dev->chan_attr_group.attrs[0]),
803 GFP_KERNEL);
804 if (indio_dev->chan_attr_group.attrs == NULL) {
805 ret = -ENOMEM;
806 goto error_clear_attrs;
807 }
808 /* Copy across original attributes */
809 if (indio_dev->info->attrs)
810 memcpy(indio_dev->chan_attr_group.attrs,
811 indio_dev->info->attrs->attrs,
812 sizeof(indio_dev->chan_attr_group.attrs[0])
813 *attrcount_orig);
814 attrn = attrcount_orig;
815 /* Add all elements from the list. */
816 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
817 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
818 if (indio_dev->name)
819 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
820
821 indio_dev->groups[indio_dev->groupcounter++] =
822 &indio_dev->chan_attr_group;
823
824 return 0;
825
826 error_clear_attrs:
827 list_for_each_entry_safe(p, n,
828 &indio_dev->channel_attr_list, l) {
829 list_del(&p->l);
830 iio_device_remove_and_free_read_attr(indio_dev, p);
831 }
832
833 return ret;
834 }
835
836 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
837 {
838
839 struct iio_dev_attr *p, *n;
840
841 list_for_each_entry_safe(p, n, &indio_dev->channel_attr_list, l) {
842 list_del(&p->l);
843 iio_device_remove_and_free_read_attr(indio_dev, p);
844 }
845 kfree(indio_dev->chan_attr_group.attrs);
846 }
847
848 static void iio_dev_release(struct device *device)
849 {
850 struct iio_dev *indio_dev = dev_to_iio_dev(device);
851 if (indio_dev->chrdev.dev)
852 cdev_del(&indio_dev->chrdev);
853 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
854 iio_device_unregister_trigger_consumer(indio_dev);
855 iio_device_unregister_eventset(indio_dev);
856 iio_device_unregister_sysfs(indio_dev);
857 iio_device_unregister_debugfs(indio_dev);
858
859 ida_simple_remove(&iio_ida, indio_dev->id);
860 kfree(indio_dev);
861 }
862
863 struct device_type iio_device_type = {
864 .name = "iio_device",
865 .release = iio_dev_release,
866 };
867
868 struct iio_dev *iio_device_alloc(int sizeof_priv)
869 {
870 struct iio_dev *dev;
871 size_t alloc_size;
872
873 alloc_size = sizeof(struct iio_dev);
874 if (sizeof_priv) {
875 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
876 alloc_size += sizeof_priv;
877 }
878 /* ensure 32-byte alignment of whole construct ? */
879 alloc_size += IIO_ALIGN - 1;
880
881 dev = kzalloc(alloc_size, GFP_KERNEL);
882
883 if (dev) {
884 dev->dev.groups = dev->groups;
885 dev->dev.type = &iio_device_type;
886 dev->dev.bus = &iio_bus_type;
887 device_initialize(&dev->dev);
888 dev_set_drvdata(&dev->dev, (void *)dev);
889 mutex_init(&dev->mlock);
890 mutex_init(&dev->info_exist_lock);
891 INIT_LIST_HEAD(&dev->channel_attr_list);
892
893 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
894 if (dev->id < 0) {
895 /* cannot use a dev_err as the name isn't available */
896 printk(KERN_ERR "Failed to get id\n");
897 kfree(dev);
898 return NULL;
899 }
900 dev_set_name(&dev->dev, "iio:device%d", dev->id);
901 INIT_LIST_HEAD(&dev->buffer_list);
902 }
903
904 return dev;
905 }
906 EXPORT_SYMBOL(iio_device_alloc);
907
908 void iio_device_free(struct iio_dev *dev)
909 {
910 if (dev)
911 put_device(&dev->dev);
912 }
913 EXPORT_SYMBOL(iio_device_free);
914
915 /**
916 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
917 **/
918 static int iio_chrdev_open(struct inode *inode, struct file *filp)
919 {
920 struct iio_dev *indio_dev = container_of(inode->i_cdev,
921 struct iio_dev, chrdev);
922
923 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
924 return -EBUSY;
925
926 filp->private_data = indio_dev;
927
928 return 0;
929 }
930
931 /**
932 * iio_chrdev_release() - chrdev file close buffer access and ioctls
933 **/
934 static int iio_chrdev_release(struct inode *inode, struct file *filp)
935 {
936 struct iio_dev *indio_dev = container_of(inode->i_cdev,
937 struct iio_dev, chrdev);
938 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
939 return 0;
940 }
941
942 /* Somewhat of a cross file organization violation - ioctls here are actually
943 * event related */
944 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
945 {
946 struct iio_dev *indio_dev = filp->private_data;
947 int __user *ip = (int __user *)arg;
948 int fd;
949
950 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
951 fd = iio_event_getfd(indio_dev);
952 if (copy_to_user(ip, &fd, sizeof(fd)))
953 return -EFAULT;
954 return 0;
955 }
956 return -EINVAL;
957 }
958
959 static const struct file_operations iio_buffer_fileops = {
960 .read = iio_buffer_read_first_n_outer_addr,
961 .release = iio_chrdev_release,
962 .open = iio_chrdev_open,
963 .poll = iio_buffer_poll_addr,
964 .owner = THIS_MODULE,
965 .llseek = noop_llseek,
966 .unlocked_ioctl = iio_ioctl,
967 .compat_ioctl = iio_ioctl,
968 };
969
970 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
971
972 int iio_device_register(struct iio_dev *indio_dev)
973 {
974 int ret;
975
976 /* If the calling driver did not initialize of_node, do it here */
977 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
978 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
979
980 /* configure elements for the chrdev */
981 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
982
983 ret = iio_device_register_debugfs(indio_dev);
984 if (ret) {
985 dev_err(indio_dev->dev.parent,
986 "Failed to register debugfs interfaces\n");
987 goto error_ret;
988 }
989 ret = iio_device_register_sysfs(indio_dev);
990 if (ret) {
991 dev_err(indio_dev->dev.parent,
992 "Failed to register sysfs interfaces\n");
993 goto error_unreg_debugfs;
994 }
995 ret = iio_device_register_eventset(indio_dev);
996 if (ret) {
997 dev_err(indio_dev->dev.parent,
998 "Failed to register event set\n");
999 goto error_free_sysfs;
1000 }
1001 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
1002 iio_device_register_trigger_consumer(indio_dev);
1003
1004 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1005 indio_dev->setup_ops == NULL)
1006 indio_dev->setup_ops = &noop_ring_setup_ops;
1007
1008 ret = device_add(&indio_dev->dev);
1009 if (ret < 0)
1010 goto error_unreg_eventset;
1011 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1012 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1013 ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
1014 if (ret < 0)
1015 goto error_del_device;
1016 return 0;
1017
1018 error_del_device:
1019 device_del(&indio_dev->dev);
1020 error_unreg_eventset:
1021 iio_device_unregister_eventset(indio_dev);
1022 error_free_sysfs:
1023 iio_device_unregister_sysfs(indio_dev);
1024 error_unreg_debugfs:
1025 iio_device_unregister_debugfs(indio_dev);
1026 error_ret:
1027 return ret;
1028 }
1029 EXPORT_SYMBOL(iio_device_register);
1030
1031 void iio_device_unregister(struct iio_dev *indio_dev)
1032 {
1033 mutex_lock(&indio_dev->info_exist_lock);
1034 indio_dev->info = NULL;
1035 mutex_unlock(&indio_dev->info_exist_lock);
1036 device_del(&indio_dev->dev);
1037 }
1038 EXPORT_SYMBOL(iio_device_unregister);
1039 subsys_initcall(iio_init);
1040 module_exit(iio_exit);
1041
1042 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1043 MODULE_DESCRIPTION("Industrial I/O core");
1044 MODULE_LICENSE("GPL");