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 "iio.h"
26 #include "iio_core.h"
27 #include "iio_core_trigger.h"
28 #include "sysfs.h"
29 #include "events.h"
30
31 /* IDA to assign each registered device a unique id*/
32 static DEFINE_IDA(iio_ida);
33
34 static dev_t iio_devt;
35
36 #define IIO_DEV_MAX 256
37 struct bus_type iio_bus_type = {
38 .name = "iio",
39 };
40 EXPORT_SYMBOL(iio_bus_type);
41
42 static const char * const iio_data_type_name[] = {
43 [IIO_RAW] = "raw",
44 [IIO_PROCESSED] = "input",
45 };
46
47 static const char * const iio_direction[] = {
48 [0] = "in",
49 [1] = "out",
50 };
51
52 static const char * const iio_chan_type_name_spec[] = {
53 [IIO_VOLTAGE] = "voltage",
54 [IIO_CURRENT] = "current",
55 [IIO_POWER] = "power",
56 [IIO_ACCEL] = "accel",
57 [IIO_ANGL_VEL] = "anglvel",
58 [IIO_MAGN] = "magn",
59 [IIO_LIGHT] = "illuminance",
60 [IIO_INTENSITY] = "intensity",
61 [IIO_PROXIMITY] = "proximity",
62 [IIO_TEMP] = "temp",
63 [IIO_INCLI] = "incli",
64 [IIO_ROT] = "rot",
65 [IIO_ANGL] = "angl",
66 [IIO_TIMESTAMP] = "timestamp",
67 [IIO_CAPACITANCE] = "capacitance",
68 };
69
70 static const char * const iio_modifier_names[] = {
71 [IIO_MOD_X] = "x",
72 [IIO_MOD_Y] = "y",
73 [IIO_MOD_Z] = "z",
74 [IIO_MOD_LIGHT_BOTH] = "both",
75 [IIO_MOD_LIGHT_IR] = "ir",
76 };
77
78 /* relies on pairs of these shared then separate */
79 static const char * const iio_chan_info_postfix[] = {
80 [IIO_CHAN_INFO_SCALE] = "scale",
81 [IIO_CHAN_INFO_OFFSET] = "offset",
82 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
83 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
84 [IIO_CHAN_INFO_PEAK] = "peak_raw",
85 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
86 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
87 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
88 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
89 = "filter_low_pass_3db_frequency",
90 };
91
92 const struct iio_chan_spec
iio_find_channel_from_si(struct iio_dev * indio_dev,int si)93 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
94 {
95 int i;
96
97 for (i = 0; i < indio_dev->num_channels; i++)
98 if (indio_dev->channels[i].scan_index == si)
99 return &indio_dev->channels[i];
100 return NULL;
101 }
102
103 /**
104 * struct iio_detected_event_list - list element for events that have occurred
105 * @list: linked list header
106 * @ev: the event itself
107 */
108 struct iio_detected_event_list {
109 struct list_head list;
110 struct iio_event_data ev;
111 };
112
113 /**
114 * struct iio_event_interface - chrdev interface for an event line
115 * @dev: device assocated with event interface
116 * @wait: wait queue to allow blocking reads of events
117 * @event_list_lock: mutex to protect the list of detected events
118 * @det_events: list of detected events
119 * @max_events: maximum number of events before new ones are dropped
120 * @current_events: number of events in detected list
121 * @flags: file operations related flags including busy flag.
122 */
123 struct iio_event_interface {
124 wait_queue_head_t wait;
125 struct mutex event_list_lock;
126 struct list_head det_events;
127 int max_events;
128 int current_events;
129 struct list_head dev_attr_list;
130 unsigned long flags;
131 struct attribute_group group;
132 };
133
iio_push_event(struct iio_dev * indio_dev,u64 ev_code,s64 timestamp)134 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp)
135 {
136 struct iio_event_interface *ev_int = indio_dev->event_interface;
137 struct iio_detected_event_list *ev;
138 int ret = 0;
139
140 /* Does anyone care? */
141 mutex_lock(&ev_int->event_list_lock);
142 if (test_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
143 if (ev_int->current_events == ev_int->max_events) {
144 mutex_unlock(&ev_int->event_list_lock);
145 return 0;
146 }
147 ev = kmalloc(sizeof(*ev), GFP_KERNEL);
148 if (ev == NULL) {
149 ret = -ENOMEM;
150 mutex_unlock(&ev_int->event_list_lock);
151 goto error_ret;
152 }
153 ev->ev.id = ev_code;
154 ev->ev.timestamp = timestamp;
155
156 list_add_tail(&ev->list, &ev_int->det_events);
157 ev_int->current_events++;
158 mutex_unlock(&ev_int->event_list_lock);
159 wake_up_interruptible(&ev_int->wait);
160 } else
161 mutex_unlock(&ev_int->event_list_lock);
162
163 error_ret:
164 return ret;
165 }
166 EXPORT_SYMBOL(iio_push_event);
167
168 /* This turns up an awful lot */
iio_read_const_attr(struct device * dev,struct device_attribute * attr,char * buf)169 ssize_t iio_read_const_attr(struct device *dev,
170 struct device_attribute *attr,
171 char *buf)
172 {
173 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
174 }
175 EXPORT_SYMBOL(iio_read_const_attr);
176
iio_event_chrdev_read(struct file * filep,char __user * buf,size_t count,loff_t * f_ps)177 static ssize_t iio_event_chrdev_read(struct file *filep,
178 char __user *buf,
179 size_t count,
180 loff_t *f_ps)
181 {
182 struct iio_event_interface *ev_int = filep->private_data;
183 struct iio_detected_event_list *el;
184 size_t len = sizeof(el->ev);
185 int ret;
186
187 if (count < len)
188 return -EINVAL;
189
190 mutex_lock(&ev_int->event_list_lock);
191 if (list_empty(&ev_int->det_events)) {
192 if (filep->f_flags & O_NONBLOCK) {
193 ret = -EAGAIN;
194 goto error_mutex_unlock;
195 }
196 mutex_unlock(&ev_int->event_list_lock);
197 /* Blocking on device; waiting for something to be there */
198 ret = wait_event_interruptible(ev_int->wait,
199 !list_empty(&ev_int
200 ->det_events));
201 if (ret)
202 goto error_ret;
203 /* Single access device so no one else can get the data */
204 mutex_lock(&ev_int->event_list_lock);
205 }
206
207 el = list_first_entry(&ev_int->det_events,
208 struct iio_detected_event_list,
209 list);
210 if (copy_to_user(buf, &(el->ev), len)) {
211 ret = -EFAULT;
212 goto error_mutex_unlock;
213 }
214 list_del(&el->list);
215 ev_int->current_events--;
216 mutex_unlock(&ev_int->event_list_lock);
217 kfree(el);
218
219 return len;
220
221 error_mutex_unlock:
222 mutex_unlock(&ev_int->event_list_lock);
223 error_ret:
224
225 return ret;
226 }
227
iio_event_chrdev_release(struct inode * inode,struct file * filep)228 static int iio_event_chrdev_release(struct inode *inode, struct file *filep)
229 {
230 struct iio_event_interface *ev_int = filep->private_data;
231 struct iio_detected_event_list *el, *t;
232
233 mutex_lock(&ev_int->event_list_lock);
234 clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
235 /*
236 * In order to maintain a clean state for reopening,
237 * clear out any awaiting events. The mask will prevent
238 * any new __iio_push_event calls running.
239 */
240 list_for_each_entry_safe(el, t, &ev_int->det_events, list) {
241 list_del(&el->list);
242 kfree(el);
243 }
244 ev_int->current_events = 0;
245 mutex_unlock(&ev_int->event_list_lock);
246
247 return 0;
248 }
249
250 static const struct file_operations iio_event_chrdev_fileops = {
251 .read = iio_event_chrdev_read,
252 .release = iio_event_chrdev_release,
253 .owner = THIS_MODULE,
254 .llseek = noop_llseek,
255 };
256
iio_event_getfd(struct iio_dev * indio_dev)257 static int iio_event_getfd(struct iio_dev *indio_dev)
258 {
259 struct iio_event_interface *ev_int = indio_dev->event_interface;
260 int fd;
261
262 if (ev_int == NULL)
263 return -ENODEV;
264
265 mutex_lock(&ev_int->event_list_lock);
266 if (test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
267 mutex_unlock(&ev_int->event_list_lock);
268 return -EBUSY;
269 }
270 mutex_unlock(&ev_int->event_list_lock);
271 fd = anon_inode_getfd("iio:event",
272 &iio_event_chrdev_fileops, ev_int, O_RDONLY);
273 if (fd < 0) {
274 mutex_lock(&ev_int->event_list_lock);
275 clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
276 mutex_unlock(&ev_int->event_list_lock);
277 }
278 return fd;
279 }
280
iio_init(void)281 static int __init iio_init(void)
282 {
283 int ret;
284
285 /* Register sysfs bus */
286 ret = bus_register(&iio_bus_type);
287 if (ret < 0) {
288 printk(KERN_ERR
289 "%s could not register bus type\n",
290 __FILE__);
291 goto error_nothing;
292 }
293
294 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
295 if (ret < 0) {
296 printk(KERN_ERR "%s: failed to allocate char dev region\n",
297 __FILE__);
298 goto error_unregister_bus_type;
299 }
300
301 return 0;
302
303 error_unregister_bus_type:
304 bus_unregister(&iio_bus_type);
305 error_nothing:
306 return ret;
307 }
308
iio_exit(void)309 static void __exit iio_exit(void)
310 {
311 if (iio_devt)
312 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
313 bus_unregister(&iio_bus_type);
314 }
315
iio_read_channel_info(struct device * dev,struct device_attribute * attr,char * buf)316 static ssize_t iio_read_channel_info(struct device *dev,
317 struct device_attribute *attr,
318 char *buf)
319 {
320 struct iio_dev *indio_dev = dev_get_drvdata(dev);
321 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
322 int val, val2;
323 int ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
324 &val, &val2, this_attr->address);
325
326 if (ret < 0)
327 return ret;
328
329 if (ret == IIO_VAL_INT)
330 return sprintf(buf, "%d\n", val);
331 else if (ret == IIO_VAL_INT_PLUS_MICRO) {
332 if (val2 < 0)
333 return sprintf(buf, "-%d.%06u\n", val, -val2);
334 else
335 return sprintf(buf, "%d.%06u\n", val, val2);
336 } else if (ret == IIO_VAL_INT_PLUS_NANO) {
337 if (val2 < 0)
338 return sprintf(buf, "-%d.%09u\n", val, -val2);
339 else
340 return sprintf(buf, "%d.%09u\n", val, val2);
341 } else
342 return 0;
343 }
344
iio_write_channel_info(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)345 static ssize_t iio_write_channel_info(struct device *dev,
346 struct device_attribute *attr,
347 const char *buf,
348 size_t len)
349 {
350 struct iio_dev *indio_dev = dev_get_drvdata(dev);
351 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
352 int ret, integer = 0, fract = 0, fract_mult = 100000;
353 bool integer_part = true, negative = false;
354
355 /* Assumes decimal - precision based on number of digits */
356 if (!indio_dev->info->write_raw)
357 return -EINVAL;
358
359 if (indio_dev->info->write_raw_get_fmt)
360 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
361 this_attr->c, this_attr->address)) {
362 case IIO_VAL_INT_PLUS_MICRO:
363 fract_mult = 100000;
364 break;
365 case IIO_VAL_INT_PLUS_NANO:
366 fract_mult = 100000000;
367 break;
368 default:
369 return -EINVAL;
370 }
371
372 if (buf[0] == '-') {
373 negative = true;
374 buf++;
375 }
376
377 while (*buf) {
378 if ('0' <= *buf && *buf <= '9') {
379 if (integer_part)
380 integer = integer*10 + *buf - '0';
381 else {
382 fract += fract_mult*(*buf - '0');
383 if (fract_mult == 1)
384 break;
385 fract_mult /= 10;
386 }
387 } else if (*buf == '\n') {
388 if (*(buf + 1) == '\0')
389 break;
390 else
391 return -EINVAL;
392 } else if (*buf == '.') {
393 integer_part = false;
394 } else {
395 return -EINVAL;
396 }
397 buf++;
398 }
399 if (negative) {
400 if (integer)
401 integer = -integer;
402 else
403 fract = -fract;
404 }
405
406 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
407 integer, fract, this_attr->address);
408 if (ret)
409 return ret;
410
411 return len;
412 }
413
414 static
__iio_device_attr_init(struct device_attribute * dev_attr,const char * postfix,struct iio_chan_spec const * chan,ssize_t (* readfunc)(struct device * dev,struct device_attribute * attr,char * buf),ssize_t (* writefunc)(struct device * dev,struct device_attribute * attr,const char * buf,size_t len),bool generic)415 int __iio_device_attr_init(struct device_attribute *dev_attr,
416 const char *postfix,
417 struct iio_chan_spec const *chan,
418 ssize_t (*readfunc)(struct device *dev,
419 struct device_attribute *attr,
420 char *buf),
421 ssize_t (*writefunc)(struct device *dev,
422 struct device_attribute *attr,
423 const char *buf,
424 size_t len),
425 bool generic)
426 {
427 int ret;
428 char *name_format, *full_postfix;
429 sysfs_attr_init(&dev_attr->attr);
430
431 /* Build up postfix of <extend_name>_<modifier>_postfix */
432 if (chan->modified && !generic) {
433 if (chan->extend_name)
434 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
435 iio_modifier_names[chan
436 ->channel2],
437 chan->extend_name,
438 postfix);
439 else
440 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
441 iio_modifier_names[chan
442 ->channel2],
443 postfix);
444 } else {
445 if (chan->extend_name == NULL)
446 full_postfix = kstrdup(postfix, GFP_KERNEL);
447 else
448 full_postfix = kasprintf(GFP_KERNEL,
449 "%s_%s",
450 chan->extend_name,
451 postfix);
452 }
453 if (full_postfix == NULL) {
454 ret = -ENOMEM;
455 goto error_ret;
456 }
457
458 if (chan->differential) { /* Differential can not have modifier */
459 if (generic)
460 name_format
461 = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
462 iio_direction[chan->output],
463 iio_chan_type_name_spec[chan->type],
464 iio_chan_type_name_spec[chan->type],
465 full_postfix);
466 else if (chan->indexed)
467 name_format
468 = kasprintf(GFP_KERNEL, "%s_%s%d-%s%d_%s",
469 iio_direction[chan->output],
470 iio_chan_type_name_spec[chan->type],
471 chan->channel,
472 iio_chan_type_name_spec[chan->type],
473 chan->channel2,
474 full_postfix);
475 else {
476 WARN_ON("Differential channels must be indexed\n");
477 ret = -EINVAL;
478 goto error_free_full_postfix;
479 }
480 } else { /* Single ended */
481 if (generic)
482 name_format
483 = kasprintf(GFP_KERNEL, "%s_%s_%s",
484 iio_direction[chan->output],
485 iio_chan_type_name_spec[chan->type],
486 full_postfix);
487 else if (chan->indexed)
488 name_format
489 = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
490 iio_direction[chan->output],
491 iio_chan_type_name_spec[chan->type],
492 chan->channel,
493 full_postfix);
494 else
495 name_format
496 = kasprintf(GFP_KERNEL, "%s_%s_%s",
497 iio_direction[chan->output],
498 iio_chan_type_name_spec[chan->type],
499 full_postfix);
500 }
501 if (name_format == NULL) {
502 ret = -ENOMEM;
503 goto error_free_full_postfix;
504 }
505 dev_attr->attr.name = kasprintf(GFP_KERNEL,
506 name_format,
507 chan->channel,
508 chan->channel2);
509 if (dev_attr->attr.name == NULL) {
510 ret = -ENOMEM;
511 goto error_free_name_format;
512 }
513
514 if (readfunc) {
515 dev_attr->attr.mode |= S_IRUGO;
516 dev_attr->show = readfunc;
517 }
518
519 if (writefunc) {
520 dev_attr->attr.mode |= S_IWUSR;
521 dev_attr->store = writefunc;
522 }
523 kfree(name_format);
524 kfree(full_postfix);
525
526 return 0;
527
528 error_free_name_format:
529 kfree(name_format);
530 error_free_full_postfix:
531 kfree(full_postfix);
532 error_ret:
533 return ret;
534 }
535
__iio_device_attr_deinit(struct device_attribute * dev_attr)536 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
537 {
538 kfree(dev_attr->attr.name);
539 }
540
__iio_add_chan_devattr(const char * postfix,struct iio_chan_spec const * chan,ssize_t (* readfunc)(struct device * dev,struct device_attribute * attr,char * buf),ssize_t (* writefunc)(struct device * dev,struct device_attribute * attr,const char * buf,size_t len),u64 mask,bool generic,struct device * dev,struct list_head * attr_list)541 int __iio_add_chan_devattr(const char *postfix,
542 struct iio_chan_spec const *chan,
543 ssize_t (*readfunc)(struct device *dev,
544 struct device_attribute *attr,
545 char *buf),
546 ssize_t (*writefunc)(struct device *dev,
547 struct device_attribute *attr,
548 const char *buf,
549 size_t len),
550 u64 mask,
551 bool generic,
552 struct device *dev,
553 struct list_head *attr_list)
554 {
555 int ret;
556 struct iio_dev_attr *iio_attr, *t;
557
558 iio_attr = kzalloc(sizeof *iio_attr, GFP_KERNEL);
559 if (iio_attr == NULL) {
560 ret = -ENOMEM;
561 goto error_ret;
562 }
563 ret = __iio_device_attr_init(&iio_attr->dev_attr,
564 postfix, chan,
565 readfunc, writefunc, generic);
566 if (ret)
567 goto error_iio_dev_attr_free;
568 iio_attr->c = chan;
569 iio_attr->address = mask;
570 list_for_each_entry(t, attr_list, l)
571 if (strcmp(t->dev_attr.attr.name,
572 iio_attr->dev_attr.attr.name) == 0) {
573 if (!generic)
574 dev_err(dev, "tried to double register : %s\n",
575 t->dev_attr.attr.name);
576 ret = -EBUSY;
577 goto error_device_attr_deinit;
578 }
579 list_add(&iio_attr->l, attr_list);
580
581 return 0;
582
583 error_device_attr_deinit:
584 __iio_device_attr_deinit(&iio_attr->dev_attr);
585 error_iio_dev_attr_free:
586 kfree(iio_attr);
587 error_ret:
588 return ret;
589 }
590
iio_device_add_channel_sysfs(struct iio_dev * indio_dev,struct iio_chan_spec const * chan)591 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
592 struct iio_chan_spec const *chan)
593 {
594 int ret, i, attrcount = 0;
595
596 if (chan->channel < 0)
597 return 0;
598
599 ret = __iio_add_chan_devattr(iio_data_type_name[chan->processed_val],
600 chan,
601 &iio_read_channel_info,
602 (chan->output ?
603 &iio_write_channel_info : NULL),
604 0,
605 0,
606 &indio_dev->dev,
607 &indio_dev->channel_attr_list);
608 if (ret)
609 goto error_ret;
610 attrcount++;
611
612 for_each_set_bit(i, &chan->info_mask, sizeof(long)*8) {
613 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i/2],
614 chan,
615 &iio_read_channel_info,
616 &iio_write_channel_info,
617 i/2,
618 !(i%2),
619 &indio_dev->dev,
620 &indio_dev->channel_attr_list);
621 if (ret == -EBUSY && (i%2 == 0)) {
622 ret = 0;
623 continue;
624 }
625 if (ret < 0)
626 goto error_ret;
627 attrcount++;
628 }
629 ret = attrcount;
630 error_ret:
631 return ret;
632 }
633
iio_device_remove_and_free_read_attr(struct iio_dev * indio_dev,struct iio_dev_attr * p)634 static void iio_device_remove_and_free_read_attr(struct iio_dev *indio_dev,
635 struct iio_dev_attr *p)
636 {
637 kfree(p->dev_attr.attr.name);
638 kfree(p);
639 }
640
iio_show_dev_name(struct device * dev,struct device_attribute * attr,char * buf)641 static ssize_t iio_show_dev_name(struct device *dev,
642 struct device_attribute *attr,
643 char *buf)
644 {
645 struct iio_dev *indio_dev = dev_get_drvdata(dev);
646 return sprintf(buf, "%s\n", indio_dev->name);
647 }
648
649 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
650
iio_device_register_sysfs(struct iio_dev * indio_dev)651 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
652 {
653 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
654 struct iio_dev_attr *p, *n;
655 struct attribute **attr;
656
657 /* First count elements in any existing group */
658 if (indio_dev->info->attrs) {
659 attr = indio_dev->info->attrs->attrs;
660 while (*attr++ != NULL)
661 attrcount_orig++;
662 }
663 attrcount = attrcount_orig;
664 /*
665 * New channel registration method - relies on the fact a group does
666 * not need to be initialized if it is name is NULL.
667 */
668 INIT_LIST_HEAD(&indio_dev->channel_attr_list);
669 if (indio_dev->channels)
670 for (i = 0; i < indio_dev->num_channels; i++) {
671 ret = iio_device_add_channel_sysfs(indio_dev,
672 &indio_dev
673 ->channels[i]);
674 if (ret < 0)
675 goto error_clear_attrs;
676 attrcount += ret;
677 }
678
679 if (indio_dev->name)
680 attrcount++;
681
682 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
683 sizeof(indio_dev->chan_attr_group.attrs[0]),
684 GFP_KERNEL);
685 if (indio_dev->chan_attr_group.attrs == NULL) {
686 ret = -ENOMEM;
687 goto error_clear_attrs;
688 }
689 /* Copy across original attributes */
690 if (indio_dev->info->attrs)
691 memcpy(indio_dev->chan_attr_group.attrs,
692 indio_dev->info->attrs->attrs,
693 sizeof(indio_dev->chan_attr_group.attrs[0])
694 *attrcount_orig);
695 attrn = attrcount_orig;
696 /* Add all elements from the list. */
697 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
698 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
699 if (indio_dev->name)
700 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
701
702 indio_dev->groups[indio_dev->groupcounter++] =
703 &indio_dev->chan_attr_group;
704
705 return 0;
706
707 error_clear_attrs:
708 list_for_each_entry_safe(p, n,
709 &indio_dev->channel_attr_list, l) {
710 list_del(&p->l);
711 iio_device_remove_and_free_read_attr(indio_dev, p);
712 }
713
714 return ret;
715 }
716
iio_device_unregister_sysfs(struct iio_dev * indio_dev)717 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
718 {
719
720 struct iio_dev_attr *p, *n;
721
722 list_for_each_entry_safe(p, n, &indio_dev->channel_attr_list, l) {
723 list_del(&p->l);
724 iio_device_remove_and_free_read_attr(indio_dev, p);
725 }
726 kfree(indio_dev->chan_attr_group.attrs);
727 }
728
729 static const char * const iio_ev_type_text[] = {
730 [IIO_EV_TYPE_THRESH] = "thresh",
731 [IIO_EV_TYPE_MAG] = "mag",
732 [IIO_EV_TYPE_ROC] = "roc",
733 [IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
734 [IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
735 };
736
737 static const char * const iio_ev_dir_text[] = {
738 [IIO_EV_DIR_EITHER] = "either",
739 [IIO_EV_DIR_RISING] = "rising",
740 [IIO_EV_DIR_FALLING] = "falling"
741 };
742
iio_ev_state_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)743 static ssize_t iio_ev_state_store(struct device *dev,
744 struct device_attribute *attr,
745 const char *buf,
746 size_t len)
747 {
748 struct iio_dev *indio_dev = dev_get_drvdata(dev);
749 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
750 int ret;
751 bool val;
752
753 ret = strtobool(buf, &val);
754 if (ret < 0)
755 return ret;
756
757 ret = indio_dev->info->write_event_config(indio_dev,
758 this_attr->address,
759 val);
760 return (ret < 0) ? ret : len;
761 }
762
iio_ev_state_show(struct device * dev,struct device_attribute * attr,char * buf)763 static ssize_t iio_ev_state_show(struct device *dev,
764 struct device_attribute *attr,
765 char *buf)
766 {
767 struct iio_dev *indio_dev = dev_get_drvdata(dev);
768 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
769 int val = indio_dev->info->read_event_config(indio_dev,
770 this_attr->address);
771
772 if (val < 0)
773 return val;
774 else
775 return sprintf(buf, "%d\n", val);
776 }
777
iio_ev_value_show(struct device * dev,struct device_attribute * attr,char * buf)778 static ssize_t iio_ev_value_show(struct device *dev,
779 struct device_attribute *attr,
780 char *buf)
781 {
782 struct iio_dev *indio_dev = dev_get_drvdata(dev);
783 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
784 int val, ret;
785
786 ret = indio_dev->info->read_event_value(indio_dev,
787 this_attr->address, &val);
788 if (ret < 0)
789 return ret;
790
791 return sprintf(buf, "%d\n", val);
792 }
793
iio_ev_value_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)794 static ssize_t iio_ev_value_store(struct device *dev,
795 struct device_attribute *attr,
796 const char *buf,
797 size_t len)
798 {
799 struct iio_dev *indio_dev = dev_get_drvdata(dev);
800 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
801 unsigned long val;
802 int ret;
803
804 if (!indio_dev->info->write_event_value)
805 return -EINVAL;
806
807 ret = strict_strtoul(buf, 10, &val);
808 if (ret)
809 return ret;
810
811 ret = indio_dev->info->write_event_value(indio_dev, this_attr->address,
812 val);
813 if (ret < 0)
814 return ret;
815
816 return len;
817 }
818
iio_device_add_event_sysfs(struct iio_dev * indio_dev,struct iio_chan_spec const * chan)819 static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
820 struct iio_chan_spec const *chan)
821 {
822 int ret = 0, i, attrcount = 0;
823 u64 mask = 0;
824 char *postfix;
825 if (!chan->event_mask)
826 return 0;
827
828 for_each_set_bit(i, &chan->event_mask, sizeof(chan->event_mask)*8) {
829 postfix = kasprintf(GFP_KERNEL, "%s_%s_en",
830 iio_ev_type_text[i/IIO_EV_DIR_MAX],
831 iio_ev_dir_text[i%IIO_EV_DIR_MAX]);
832 if (postfix == NULL) {
833 ret = -ENOMEM;
834 goto error_ret;
835 }
836 if (chan->modified)
837 mask = IIO_MOD_EVENT_CODE(chan->type, 0, chan->channel,
838 i/IIO_EV_DIR_MAX,
839 i%IIO_EV_DIR_MAX);
840 else if (chan->differential)
841 mask = IIO_EVENT_CODE(chan->type,
842 0, 0,
843 i%IIO_EV_DIR_MAX,
844 i/IIO_EV_DIR_MAX,
845 0,
846 chan->channel,
847 chan->channel2);
848 else
849 mask = IIO_UNMOD_EVENT_CODE(chan->type,
850 chan->channel,
851 i/IIO_EV_DIR_MAX,
852 i%IIO_EV_DIR_MAX);
853
854 ret = __iio_add_chan_devattr(postfix,
855 chan,
856 &iio_ev_state_show,
857 iio_ev_state_store,
858 mask,
859 0,
860 &indio_dev->dev,
861 &indio_dev->event_interface->
862 dev_attr_list);
863 kfree(postfix);
864 if (ret)
865 goto error_ret;
866 attrcount++;
867 postfix = kasprintf(GFP_KERNEL, "%s_%s_value",
868 iio_ev_type_text[i/IIO_EV_DIR_MAX],
869 iio_ev_dir_text[i%IIO_EV_DIR_MAX]);
870 if (postfix == NULL) {
871 ret = -ENOMEM;
872 goto error_ret;
873 }
874 ret = __iio_add_chan_devattr(postfix, chan,
875 iio_ev_value_show,
876 iio_ev_value_store,
877 mask,
878 0,
879 &indio_dev->dev,
880 &indio_dev->event_interface->
881 dev_attr_list);
882 kfree(postfix);
883 if (ret)
884 goto error_ret;
885 attrcount++;
886 }
887 ret = attrcount;
888 error_ret:
889 return ret;
890 }
891
__iio_remove_event_config_attrs(struct iio_dev * indio_dev)892 static inline void __iio_remove_event_config_attrs(struct iio_dev *indio_dev)
893 {
894 struct iio_dev_attr *p, *n;
895 list_for_each_entry_safe(p, n,
896 &indio_dev->event_interface->
897 dev_attr_list, l) {
898 kfree(p->dev_attr.attr.name);
899 kfree(p);
900 }
901 }
902
__iio_add_event_config_attrs(struct iio_dev * indio_dev)903 static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
904 {
905 int j, ret, attrcount = 0;
906
907 INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);
908 /* Dynically created from the channels array */
909 for (j = 0; j < indio_dev->num_channels; j++) {
910 ret = iio_device_add_event_sysfs(indio_dev,
911 &indio_dev->channels[j]);
912 if (ret < 0)
913 goto error_clear_attrs;
914 attrcount += ret;
915 }
916 return attrcount;
917
918 error_clear_attrs:
919 __iio_remove_event_config_attrs(indio_dev);
920
921 return ret;
922 }
923
iio_check_for_dynamic_events(struct iio_dev * indio_dev)924 static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
925 {
926 int j;
927
928 for (j = 0; j < indio_dev->num_channels; j++)
929 if (indio_dev->channels[j].event_mask != 0)
930 return true;
931 return false;
932 }
933
iio_setup_ev_int(struct iio_event_interface * ev_int)934 static void iio_setup_ev_int(struct iio_event_interface *ev_int)
935 {
936 mutex_init(&ev_int->event_list_lock);
937 /* discussion point - make this variable? */
938 ev_int->max_events = 10;
939 ev_int->current_events = 0;
940 INIT_LIST_HEAD(&ev_int->det_events);
941 init_waitqueue_head(&ev_int->wait);
942 }
943
944 static const char *iio_event_group_name = "events";
iio_device_register_eventset(struct iio_dev * indio_dev)945 static int iio_device_register_eventset(struct iio_dev *indio_dev)
946 {
947 struct iio_dev_attr *p;
948 int ret = 0, attrcount_orig = 0, attrcount, attrn;
949 struct attribute **attr;
950
951 if (!(indio_dev->info->event_attrs ||
952 iio_check_for_dynamic_events(indio_dev)))
953 return 0;
954
955 indio_dev->event_interface =
956 kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
957 if (indio_dev->event_interface == NULL) {
958 ret = -ENOMEM;
959 goto error_ret;
960 }
961
962 iio_setup_ev_int(indio_dev->event_interface);
963 if (indio_dev->info->event_attrs != NULL) {
964 attr = indio_dev->info->event_attrs->attrs;
965 while (*attr++ != NULL)
966 attrcount_orig++;
967 }
968 attrcount = attrcount_orig;
969 if (indio_dev->channels) {
970 ret = __iio_add_event_config_attrs(indio_dev);
971 if (ret < 0)
972 goto error_free_setup_event_lines;
973 attrcount += ret;
974 }
975
976 indio_dev->event_interface->group.name = iio_event_group_name;
977 indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
978 sizeof(indio_dev->event_interface->group.attrs[0]),
979 GFP_KERNEL);
980 if (indio_dev->event_interface->group.attrs == NULL) {
981 ret = -ENOMEM;
982 goto error_free_setup_event_lines;
983 }
984 if (indio_dev->info->event_attrs)
985 memcpy(indio_dev->event_interface->group.attrs,
986 indio_dev->info->event_attrs->attrs,
987 sizeof(indio_dev->event_interface->group.attrs[0])
988 *attrcount_orig);
989 attrn = attrcount_orig;
990 /* Add all elements from the list. */
991 list_for_each_entry(p,
992 &indio_dev->event_interface->dev_attr_list,
993 l)
994 indio_dev->event_interface->group.attrs[attrn++] =
995 &p->dev_attr.attr;
996 indio_dev->groups[indio_dev->groupcounter++] =
997 &indio_dev->event_interface->group;
998
999 return 0;
1000
1001 error_free_setup_event_lines:
1002 __iio_remove_event_config_attrs(indio_dev);
1003 kfree(indio_dev->event_interface);
1004 error_ret:
1005
1006 return ret;
1007 }
1008
iio_device_unregister_eventset(struct iio_dev * indio_dev)1009 static void iio_device_unregister_eventset(struct iio_dev *indio_dev)
1010 {
1011 if (indio_dev->event_interface == NULL)
1012 return;
1013 __iio_remove_event_config_attrs(indio_dev);
1014 kfree(indio_dev->event_interface->group.attrs);
1015 kfree(indio_dev->event_interface);
1016 }
1017
iio_dev_release(struct device * device)1018 static void iio_dev_release(struct device *device)
1019 {
1020 struct iio_dev *indio_dev = container_of(device, struct iio_dev, dev);
1021 cdev_del(&indio_dev->chrdev);
1022 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
1023 iio_device_unregister_trigger_consumer(indio_dev);
1024 iio_device_unregister_eventset(indio_dev);
1025 iio_device_unregister_sysfs(indio_dev);
1026 }
1027
1028 static struct device_type iio_dev_type = {
1029 .name = "iio_device",
1030 .release = iio_dev_release,
1031 };
1032
iio_allocate_device(int sizeof_priv)1033 struct iio_dev *iio_allocate_device(int sizeof_priv)
1034 {
1035 struct iio_dev *dev;
1036 size_t alloc_size;
1037
1038 alloc_size = sizeof(struct iio_dev);
1039 if (sizeof_priv) {
1040 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1041 alloc_size += sizeof_priv;
1042 }
1043 /* ensure 32-byte alignment of whole construct ? */
1044 alloc_size += IIO_ALIGN - 1;
1045
1046 dev = kzalloc(alloc_size, GFP_KERNEL);
1047
1048 if (dev) {
1049 dev->dev.groups = dev->groups;
1050 dev->dev.type = &iio_dev_type;
1051 dev->dev.bus = &iio_bus_type;
1052 device_initialize(&dev->dev);
1053 dev_set_drvdata(&dev->dev, (void *)dev);
1054 mutex_init(&dev->mlock);
1055
1056 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1057 if (dev->id < 0) {
1058 /* cannot use a dev_err as the name isn't available */
1059 printk(KERN_ERR "Failed to get id\n");
1060 kfree(dev);
1061 return NULL;
1062 }
1063 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1064 }
1065
1066 return dev;
1067 }
1068 EXPORT_SYMBOL(iio_allocate_device);
1069
iio_free_device(struct iio_dev * dev)1070 void iio_free_device(struct iio_dev *dev)
1071 {
1072 if (dev) {
1073 ida_simple_remove(&iio_ida, dev->id);
1074 kfree(dev);
1075 }
1076 }
1077 EXPORT_SYMBOL(iio_free_device);
1078
1079 /**
1080 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1081 **/
iio_chrdev_open(struct inode * inode,struct file * filp)1082 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1083 {
1084 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1085 struct iio_dev, chrdev);
1086
1087 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1088 return -EBUSY;
1089
1090 filp->private_data = indio_dev;
1091
1092 return 0;
1093 }
1094
1095 /**
1096 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1097 **/
iio_chrdev_release(struct inode * inode,struct file * filp)1098 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1099 {
1100 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1101 struct iio_dev, chrdev);
1102 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1103 return 0;
1104 }
1105
1106 /* Somewhat of a cross file organization violation - ioctls here are actually
1107 * event related */
iio_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)1108 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1109 {
1110 struct iio_dev *indio_dev = filp->private_data;
1111 int __user *ip = (int __user *)arg;
1112 int fd;
1113
1114 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1115 fd = iio_event_getfd(indio_dev);
1116 if (copy_to_user(ip, &fd, sizeof(fd)))
1117 return -EFAULT;
1118 return 0;
1119 }
1120 return -EINVAL;
1121 }
1122
1123 static const struct file_operations iio_buffer_fileops = {
1124 .read = iio_buffer_read_first_n_outer_addr,
1125 .release = iio_chrdev_release,
1126 .open = iio_chrdev_open,
1127 .poll = iio_buffer_poll_addr,
1128 .owner = THIS_MODULE,
1129 .llseek = noop_llseek,
1130 .unlocked_ioctl = iio_ioctl,
1131 .compat_ioctl = iio_ioctl,
1132 };
1133
iio_device_register(struct iio_dev * indio_dev)1134 int iio_device_register(struct iio_dev *indio_dev)
1135 {
1136 int ret;
1137
1138 /* configure elements for the chrdev */
1139 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1140
1141 ret = iio_device_register_sysfs(indio_dev);
1142 if (ret) {
1143 dev_err(indio_dev->dev.parent,
1144 "Failed to register sysfs interfaces\n");
1145 goto error_ret;
1146 }
1147 ret = iio_device_register_eventset(indio_dev);
1148 if (ret) {
1149 dev_err(indio_dev->dev.parent,
1150 "Failed to register event set\n");
1151 goto error_free_sysfs;
1152 }
1153 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
1154 iio_device_register_trigger_consumer(indio_dev);
1155
1156 ret = device_add(&indio_dev->dev);
1157 if (ret < 0)
1158 goto error_unreg_eventset;
1159 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1160 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1161 ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
1162 if (ret < 0)
1163 goto error_del_device;
1164 return 0;
1165
1166 error_del_device:
1167 device_del(&indio_dev->dev);
1168 error_unreg_eventset:
1169 iio_device_unregister_eventset(indio_dev);
1170 error_free_sysfs:
1171 iio_device_unregister_sysfs(indio_dev);
1172 error_ret:
1173 return ret;
1174 }
1175 EXPORT_SYMBOL(iio_device_register);
1176
iio_device_unregister(struct iio_dev * indio_dev)1177 void iio_device_unregister(struct iio_dev *indio_dev)
1178 {
1179 device_unregister(&indio_dev->dev);
1180 }
1181 EXPORT_SYMBOL(iio_device_unregister);
1182 subsys_initcall(iio_init);
1183 module_exit(iio_exit);
1184
1185 MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
1186 MODULE_DESCRIPTION("Industrial I/O core");
1187 MODULE_LICENSE("GPL");
1188