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12#include <linux/anon_inodes.h>
13#include <linux/device.h>
14#include <linux/fs.h>
15#include <linux/kernel.h>
16#include <linux/kfifo.h>
17#include <linux/module.h>
18#include <linux/poll.h>
19#include <linux/sched.h>
20#include <linux/slab.h>
21#include <linux/uaccess.h>
22#include <linux/wait.h>
23#include <linux/iio/iio.h>
24#include "iio_core.h"
25#include <linux/iio/sysfs.h>
26#include <linux/iio/events.h>
27
28
29
30
31
32
33
34
35
36struct iio_event_interface {
37 wait_queue_head_t wait;
38 DECLARE_KFIFO(det_events, struct iio_event_data, 16);
39
40 struct list_head dev_attr_list;
41 unsigned long flags;
42 struct attribute_group group;
43 struct mutex read_lock;
44};
45
46
47
48
49
50
51
52
53
54
55int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp)
56{
57 struct iio_event_interface *ev_int = indio_dev->event_interface;
58 struct iio_event_data ev;
59 int copied;
60
61
62 if (test_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
63
64 ev.id = ev_code;
65 ev.timestamp = timestamp;
66
67 copied = kfifo_put(&ev_int->det_events, ev);
68 if (copied != 0)
69 wake_up_poll(&ev_int->wait, POLLIN);
70 }
71
72 return 0;
73}
74EXPORT_SYMBOL(iio_push_event);
75
76
77
78
79static unsigned int iio_event_poll(struct file *filep,
80 struct poll_table_struct *wait)
81{
82 struct iio_dev *indio_dev = filep->private_data;
83 struct iio_event_interface *ev_int = indio_dev->event_interface;
84 unsigned int events = 0;
85
86 if (!indio_dev->info)
87 return -ENODEV;
88
89 poll_wait(filep, &ev_int->wait, wait);
90
91 if (!kfifo_is_empty(&ev_int->det_events))
92 events = POLLIN | POLLRDNORM;
93
94 return events;
95}
96
97static ssize_t iio_event_chrdev_read(struct file *filep,
98 char __user *buf,
99 size_t count,
100 loff_t *f_ps)
101{
102 struct iio_dev *indio_dev = filep->private_data;
103 struct iio_event_interface *ev_int = indio_dev->event_interface;
104 unsigned int copied;
105 int ret;
106
107 if (!indio_dev->info)
108 return -ENODEV;
109
110 if (count < sizeof(struct iio_event_data))
111 return -EINVAL;
112
113 do {
114 if (kfifo_is_empty(&ev_int->det_events)) {
115 if (filep->f_flags & O_NONBLOCK)
116 return -EAGAIN;
117
118 ret = wait_event_interruptible(ev_int->wait,
119 !kfifo_is_empty(&ev_int->det_events) ||
120 indio_dev->info == NULL);
121 if (ret)
122 return ret;
123 if (indio_dev->info == NULL)
124 return -ENODEV;
125 }
126
127 if (mutex_lock_interruptible(&ev_int->read_lock))
128 return -ERESTARTSYS;
129 ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied);
130 mutex_unlock(&ev_int->read_lock);
131
132 if (ret)
133 return ret;
134
135
136
137
138
139
140
141 if (copied == 0 && (filep->f_flags & O_NONBLOCK))
142 return -EAGAIN;
143
144 } while (copied == 0);
145
146 return copied;
147}
148
149static int iio_event_chrdev_release(struct inode *inode, struct file *filep)
150{
151 struct iio_dev *indio_dev = filep->private_data;
152 struct iio_event_interface *ev_int = indio_dev->event_interface;
153
154 clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
155
156 iio_device_put(indio_dev);
157
158 return 0;
159}
160
161static const struct file_operations iio_event_chrdev_fileops = {
162 .read = iio_event_chrdev_read,
163 .poll = iio_event_poll,
164 .release = iio_event_chrdev_release,
165 .owner = THIS_MODULE,
166 .llseek = noop_llseek,
167};
168
169int iio_event_getfd(struct iio_dev *indio_dev)
170{
171 struct iio_event_interface *ev_int = indio_dev->event_interface;
172 int fd;
173
174 if (ev_int == NULL)
175 return -ENODEV;
176
177 if (test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags))
178 return -EBUSY;
179
180 iio_device_get(indio_dev);
181
182 fd = anon_inode_getfd("iio:event", &iio_event_chrdev_fileops,
183 indio_dev, O_RDONLY | O_CLOEXEC);
184 if (fd < 0) {
185 clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
186 iio_device_put(indio_dev);
187 } else {
188 kfifo_reset_out(&ev_int->det_events);
189 }
190
191 return fd;
192}
193
194static const char * const iio_ev_type_text[] = {
195 [IIO_EV_TYPE_THRESH] = "thresh",
196 [IIO_EV_TYPE_MAG] = "mag",
197 [IIO_EV_TYPE_ROC] = "roc",
198 [IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
199 [IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
200 [IIO_EV_TYPE_CHANGE] = "change",
201};
202
203static const char * const iio_ev_dir_text[] = {
204 [IIO_EV_DIR_EITHER] = "either",
205 [IIO_EV_DIR_RISING] = "rising",
206 [IIO_EV_DIR_FALLING] = "falling"
207};
208
209static const char * const iio_ev_info_text[] = {
210 [IIO_EV_INFO_ENABLE] = "en",
211 [IIO_EV_INFO_VALUE] = "value",
212 [IIO_EV_INFO_HYSTERESIS] = "hysteresis",
213 [IIO_EV_INFO_PERIOD] = "period",
214};
215
216static enum iio_event_direction iio_ev_attr_dir(struct iio_dev_attr *attr)
217{
218 return attr->c->event_spec[attr->address & 0xffff].dir;
219}
220
221static enum iio_event_type iio_ev_attr_type(struct iio_dev_attr *attr)
222{
223 return attr->c->event_spec[attr->address & 0xffff].type;
224}
225
226static enum iio_event_info iio_ev_attr_info(struct iio_dev_attr *attr)
227{
228 return (attr->address >> 16) & 0xffff;
229}
230
231static ssize_t iio_ev_state_store(struct device *dev,
232 struct device_attribute *attr,
233 const char *buf,
234 size_t len)
235{
236 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
237 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
238 int ret;
239 bool val;
240
241 ret = strtobool(buf, &val);
242 if (ret < 0)
243 return ret;
244
245 ret = indio_dev->info->write_event_config(indio_dev,
246 this_attr->c, iio_ev_attr_type(this_attr),
247 iio_ev_attr_dir(this_attr), val);
248
249 return (ret < 0) ? ret : len;
250}
251
252static ssize_t iio_ev_state_show(struct device *dev,
253 struct device_attribute *attr,
254 char *buf)
255{
256 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
257 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
258 int val;
259
260 val = indio_dev->info->read_event_config(indio_dev,
261 this_attr->c, iio_ev_attr_type(this_attr),
262 iio_ev_attr_dir(this_attr));
263 if (val < 0)
264 return val;
265 else
266 return sprintf(buf, "%d\n", val);
267}
268
269static ssize_t iio_ev_value_show(struct device *dev,
270 struct device_attribute *attr,
271 char *buf)
272{
273 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
274 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
275 int val, val2, val_arr[2];
276 int ret;
277
278 ret = indio_dev->info->read_event_value(indio_dev,
279 this_attr->c, iio_ev_attr_type(this_attr),
280 iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
281 &val, &val2);
282 if (ret < 0)
283 return ret;
284 val_arr[0] = val;
285 val_arr[1] = val2;
286 return iio_format_value(buf, ret, 2, val_arr);
287}
288
289static ssize_t iio_ev_value_store(struct device *dev,
290 struct device_attribute *attr,
291 const char *buf,
292 size_t len)
293{
294 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
295 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
296 int val, val2;
297 int ret;
298
299 if (!indio_dev->info->write_event_value)
300 return -EINVAL;
301
302 ret = iio_str_to_fixpoint(buf, 100000, &val, &val2);
303 if (ret)
304 return ret;
305 ret = indio_dev->info->write_event_value(indio_dev,
306 this_attr->c, iio_ev_attr_type(this_attr),
307 iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
308 val, val2);
309 if (ret < 0)
310 return ret;
311
312 return len;
313}
314
315static int iio_device_add_event(struct iio_dev *indio_dev,
316 const struct iio_chan_spec *chan, unsigned int spec_index,
317 enum iio_event_type type, enum iio_event_direction dir,
318 enum iio_shared_by shared_by, const unsigned long *mask)
319{
320 ssize_t (*show)(struct device *, struct device_attribute *, char *);
321 ssize_t (*store)(struct device *, struct device_attribute *,
322 const char *, size_t);
323 unsigned int attrcount = 0;
324 unsigned int i;
325 char *postfix;
326 int ret;
327
328 for_each_set_bit(i, mask, sizeof(*mask)*8) {
329 if (i >= ARRAY_SIZE(iio_ev_info_text))
330 return -EINVAL;
331 if (dir != IIO_EV_DIR_NONE)
332 postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
333 iio_ev_type_text[type],
334 iio_ev_dir_text[dir],
335 iio_ev_info_text[i]);
336 else
337 postfix = kasprintf(GFP_KERNEL, "%s_%s",
338 iio_ev_type_text[type],
339 iio_ev_info_text[i]);
340 if (postfix == NULL)
341 return -ENOMEM;
342
343 if (i == IIO_EV_INFO_ENABLE) {
344 show = iio_ev_state_show;
345 store = iio_ev_state_store;
346 } else {
347 show = iio_ev_value_show;
348 store = iio_ev_value_store;
349 }
350
351 ret = __iio_add_chan_devattr(postfix, chan, show, store,
352 (i << 16) | spec_index, shared_by, &indio_dev->dev,
353 &indio_dev->event_interface->dev_attr_list);
354 kfree(postfix);
355
356 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
357 continue;
358
359 if (ret)
360 return ret;
361
362 attrcount++;
363 }
364
365 return attrcount;
366}
367
368static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
369 struct iio_chan_spec const *chan)
370{
371 int ret = 0, i, attrcount = 0;
372 enum iio_event_direction dir;
373 enum iio_event_type type;
374
375 for (i = 0; i < chan->num_event_specs; i++) {
376 type = chan->event_spec[i].type;
377 dir = chan->event_spec[i].dir;
378
379 ret = iio_device_add_event(indio_dev, chan, i, type, dir,
380 IIO_SEPARATE, &chan->event_spec[i].mask_separate);
381 if (ret < 0)
382 return ret;
383 attrcount += ret;
384
385 ret = iio_device_add_event(indio_dev, chan, i, type, dir,
386 IIO_SHARED_BY_TYPE,
387 &chan->event_spec[i].mask_shared_by_type);
388 if (ret < 0)
389 return ret;
390 attrcount += ret;
391
392 ret = iio_device_add_event(indio_dev, chan, i, type, dir,
393 IIO_SHARED_BY_DIR,
394 &chan->event_spec[i].mask_shared_by_dir);
395 if (ret < 0)
396 return ret;
397 attrcount += ret;
398
399 ret = iio_device_add_event(indio_dev, chan, i, type, dir,
400 IIO_SHARED_BY_ALL,
401 &chan->event_spec[i].mask_shared_by_all);
402 if (ret < 0)
403 return ret;
404 attrcount += ret;
405 }
406 ret = attrcount;
407 return ret;
408}
409
410static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
411{
412 int j, ret, attrcount = 0;
413
414
415 for (j = 0; j < indio_dev->num_channels; j++) {
416 ret = iio_device_add_event_sysfs(indio_dev,
417 &indio_dev->channels[j]);
418 if (ret < 0)
419 return ret;
420 attrcount += ret;
421 }
422 return attrcount;
423}
424
425static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
426{
427 int j;
428
429 for (j = 0; j < indio_dev->num_channels; j++) {
430 if (indio_dev->channels[j].num_event_specs != 0)
431 return true;
432 }
433 return false;
434}
435
436static void iio_setup_ev_int(struct iio_event_interface *ev_int)
437{
438 INIT_KFIFO(ev_int->det_events);
439 init_waitqueue_head(&ev_int->wait);
440 mutex_init(&ev_int->read_lock);
441}
442
443static const char *iio_event_group_name = "events";
444int iio_device_register_eventset(struct iio_dev *indio_dev)
445{
446 struct iio_dev_attr *p;
447 int ret = 0, attrcount_orig = 0, attrcount, attrn;
448 struct attribute **attr;
449
450 if (!(indio_dev->info->event_attrs ||
451 iio_check_for_dynamic_events(indio_dev)))
452 return 0;
453
454 indio_dev->event_interface =
455 kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
456 if (indio_dev->event_interface == NULL)
457 return -ENOMEM;
458
459 INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);
460
461 iio_setup_ev_int(indio_dev->event_interface);
462 if (indio_dev->info->event_attrs != NULL) {
463 attr = indio_dev->info->event_attrs->attrs;
464 while (*attr++ != NULL)
465 attrcount_orig++;
466 }
467 attrcount = attrcount_orig;
468 if (indio_dev->channels) {
469 ret = __iio_add_event_config_attrs(indio_dev);
470 if (ret < 0)
471 goto error_free_setup_event_lines;
472 attrcount += ret;
473 }
474
475 indio_dev->event_interface->group.name = iio_event_group_name;
476 indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
477 sizeof(indio_dev->event_interface->group.attrs[0]),
478 GFP_KERNEL);
479 if (indio_dev->event_interface->group.attrs == NULL) {
480 ret = -ENOMEM;
481 goto error_free_setup_event_lines;
482 }
483 if (indio_dev->info->event_attrs)
484 memcpy(indio_dev->event_interface->group.attrs,
485 indio_dev->info->event_attrs->attrs,
486 sizeof(indio_dev->event_interface->group.attrs[0])
487 *attrcount_orig);
488 attrn = attrcount_orig;
489
490 list_for_each_entry(p,
491 &indio_dev->event_interface->dev_attr_list,
492 l)
493 indio_dev->event_interface->group.attrs[attrn++] =
494 &p->dev_attr.attr;
495 indio_dev->groups[indio_dev->groupcounter++] =
496 &indio_dev->event_interface->group;
497
498 return 0;
499
500error_free_setup_event_lines:
501 iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
502 kfree(indio_dev->event_interface);
503 indio_dev->event_interface = NULL;
504 return ret;
505}
506
507
508
509
510
511
512
513
514void iio_device_wakeup_eventset(struct iio_dev *indio_dev)
515{
516 if (indio_dev->event_interface == NULL)
517 return;
518 wake_up(&indio_dev->event_interface->wait);
519}
520
521void iio_device_unregister_eventset(struct iio_dev *indio_dev)
522{
523 if (indio_dev->event_interface == NULL)
524 return;
525 iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
526 kfree(indio_dev->event_interface->group.attrs);
527 kfree(indio_dev->event_interface);
528}
529
