1 // SPDX-License-Identifier: GPL-2.0-only
2 /* The industrial I/O core, trigger handling functions
3 *
4 * Copyright (c) 2008 Jonathan Cameron
5 */
6
7 #include <linux/cleanup.h>
8 #include <linux/kernel.h>
9 #include <linux/idr.h>
10 #include <linux/err.h>
11 #include <linux/device.h>
12 #include <linux/interrupt.h>
13 #include <linux/list.h>
14 #include <linux/slab.h>
15
16 #include <linux/iio/iio.h>
17 #include <linux/iio/iio-opaque.h>
18 #include <linux/iio/trigger.h>
19 #include "iio_core.h"
20 #include "iio_core_trigger.h"
21 #include <linux/iio/trigger_consumer.h>
22
23 /* RFC - Question of approach
24 * Make the common case (single sensor single trigger)
25 * simple by starting trigger capture from when first sensors
26 * is added.
27 *
28 * Complex simultaneous start requires use of 'hold' functionality
29 * of the trigger. (not implemented)
30 *
31 * Any other suggestions?
32 */
33
34 static DEFINE_IDA(iio_trigger_ida);
35
36 /* Single list of all available triggers */
37 static LIST_HEAD(iio_trigger_list);
38 static DEFINE_MUTEX(iio_trigger_list_lock);
39
40 /**
41 * name_show() - retrieve useful identifying name
42 * @dev: device associated with the iio_trigger
43 * @attr: pointer to the device_attribute structure that is
44 * being processed
45 * @buf: buffer to print the name into
46 *
47 * Return: a negative number on failure or the number of written
48 * characters on success.
49 */
name_show(struct device * dev,struct device_attribute * attr,char * buf)50 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
51 char *buf)
52 {
53 struct iio_trigger *trig = to_iio_trigger(dev);
54
55 return sysfs_emit(buf, "%s\n", trig->name);
56 }
57
58 static DEVICE_ATTR_RO(name);
59
60 static struct attribute *iio_trig_dev_attrs[] = {
61 &dev_attr_name.attr,
62 NULL,
63 };
64 ATTRIBUTE_GROUPS(iio_trig_dev);
65
66 static struct iio_trigger *__iio_trigger_find_by_name(const char *name);
67
iio_trigger_register(struct iio_trigger * trig_info)68 int iio_trigger_register(struct iio_trigger *trig_info)
69 {
70 int ret;
71
72 trig_info->id = ida_alloc(&iio_trigger_ida, GFP_KERNEL);
73 if (trig_info->id < 0)
74 return trig_info->id;
75
76 /* Set the name used for the sysfs directory etc */
77 dev_set_name(&trig_info->dev, "trigger%d", trig_info->id);
78
79 ret = device_add(&trig_info->dev);
80 if (ret)
81 goto error_unregister_id;
82
83 /* Add to list of available triggers held by the IIO core */
84 scoped_guard(mutex, &iio_trigger_list_lock) {
85 if (__iio_trigger_find_by_name(trig_info->name)) {
86 pr_err("Duplicate trigger name '%s'\n", trig_info->name);
87 ret = -EEXIST;
88 goto error_device_del;
89 }
90 list_add_tail(&trig_info->list, &iio_trigger_list);
91 }
92
93 return 0;
94
95 error_device_del:
96 device_del(&trig_info->dev);
97 error_unregister_id:
98 ida_free(&iio_trigger_ida, trig_info->id);
99 return ret;
100 }
101 EXPORT_SYMBOL(iio_trigger_register);
102
iio_trigger_unregister(struct iio_trigger * trig_info)103 void iio_trigger_unregister(struct iio_trigger *trig_info)
104 {
105 scoped_guard(mutex, &iio_trigger_list_lock)
106 list_del(&trig_info->list);
107
108 ida_free(&iio_trigger_ida, trig_info->id);
109 /* Possible issue in here */
110 device_del(&trig_info->dev);
111 }
112 EXPORT_SYMBOL(iio_trigger_unregister);
113
iio_trigger_set_immutable(struct iio_dev * indio_dev,struct iio_trigger * trig)114 int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig)
115 {
116 struct iio_dev_opaque *iio_dev_opaque;
117
118 if (!indio_dev || !trig)
119 return -EINVAL;
120
121 iio_dev_opaque = to_iio_dev_opaque(indio_dev);
122 guard(mutex)(&iio_dev_opaque->mlock);
123 WARN_ON(iio_dev_opaque->trig_readonly);
124
125 indio_dev->trig = iio_trigger_get(trig);
126 iio_dev_opaque->trig_readonly = true;
127
128 return 0;
129 }
130 EXPORT_SYMBOL(iio_trigger_set_immutable);
131
132 /* Search for trigger by name, assuming iio_trigger_list_lock held */
__iio_trigger_find_by_name(const char * name)133 static struct iio_trigger *__iio_trigger_find_by_name(const char *name)
134 {
135 struct iio_trigger *iter;
136
137 list_for_each_entry(iter, &iio_trigger_list, list)
138 if (!strcmp(iter->name, name))
139 return iter;
140
141 return NULL;
142 }
143
iio_trigger_acquire_by_name(const char * name)144 static struct iio_trigger *iio_trigger_acquire_by_name(const char *name)
145 {
146 struct iio_trigger *iter;
147
148 guard(mutex)(&iio_trigger_list_lock);
149 list_for_each_entry(iter, &iio_trigger_list, list)
150 if (sysfs_streq(iter->name, name))
151 return iio_trigger_get(iter);
152
153 return NULL;
154 }
155
iio_reenable_work_fn(struct work_struct * work)156 static void iio_reenable_work_fn(struct work_struct *work)
157 {
158 struct iio_trigger *trig = container_of(work, struct iio_trigger,
159 reenable_work);
160
161 /*
162 * This 'might' occur after the trigger state is set to disabled -
163 * in that case the driver should skip reenabling.
164 */
165 trig->ops->reenable(trig);
166 }
167
168 /*
169 * In general, reenable callbacks may need to sleep and this path is
170 * not performance sensitive, so just queue up a work item
171 * to reneable the trigger for us.
172 *
173 * Races that can cause this.
174 * 1) A handler occurs entirely in interrupt context so the counter
175 * the final decrement is still in this interrupt.
176 * 2) The trigger has been removed, but one last interrupt gets through.
177 *
178 * For (1) we must call reenable, but not in atomic context.
179 * For (2) it should be safe to call reenanble, if drivers never blindly
180 * reenable after state is off.
181 */
iio_trigger_notify_done_atomic(struct iio_trigger * trig)182 static void iio_trigger_notify_done_atomic(struct iio_trigger *trig)
183 {
184 if (atomic_dec_and_test(&trig->use_count) && trig->ops &&
185 trig->ops->reenable)
186 schedule_work(&trig->reenable_work);
187 }
188
189 /**
190 * iio_trigger_poll() - Call the IRQ trigger handler of the consumers
191 * @trig: trigger which occurred
192 *
193 * This function should only be called from a hard IRQ context.
194 */
iio_trigger_poll(struct iio_trigger * trig)195 void iio_trigger_poll(struct iio_trigger *trig)
196 {
197 int i;
198
199 if (!atomic_read(&trig->use_count)) {
200 atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
201
202 for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
203 if (trig->subirqs[i].enabled)
204 generic_handle_irq(trig->subirq_base + i);
205 else
206 iio_trigger_notify_done_atomic(trig);
207 }
208 }
209 }
210 EXPORT_SYMBOL(iio_trigger_poll);
211
iio_trigger_generic_data_rdy_poll(int irq,void * private)212 irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private)
213 {
214 iio_trigger_poll(private);
215 return IRQ_HANDLED;
216 }
217 EXPORT_SYMBOL(iio_trigger_generic_data_rdy_poll);
218
219 /**
220 * iio_trigger_poll_nested() - Call the threaded trigger handler of the
221 * consumers
222 * @trig: trigger which occurred
223 *
224 * This function should only be called from a kernel thread context.
225 */
iio_trigger_poll_nested(struct iio_trigger * trig)226 void iio_trigger_poll_nested(struct iio_trigger *trig)
227 {
228 int i;
229
230 if (!atomic_read(&trig->use_count)) {
231 atomic_set(&trig->use_count, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
232
233 for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
234 if (trig->subirqs[i].enabled)
235 handle_nested_irq(trig->subirq_base + i);
236 else
237 iio_trigger_notify_done(trig);
238 }
239 }
240 }
241 EXPORT_SYMBOL(iio_trigger_poll_nested);
242
iio_trigger_notify_done(struct iio_trigger * trig)243 void iio_trigger_notify_done(struct iio_trigger *trig)
244 {
245 if (atomic_dec_and_test(&trig->use_count) && trig->ops &&
246 trig->ops->reenable)
247 trig->ops->reenable(trig);
248 }
249 EXPORT_SYMBOL(iio_trigger_notify_done);
250
251 /* Trigger Consumer related functions */
iio_trigger_get_irq(struct iio_trigger * trig)252 static int iio_trigger_get_irq(struct iio_trigger *trig)
253 {
254 int ret;
255
256 scoped_guard(mutex, &trig->pool_lock) {
257 ret = bitmap_find_free_region(trig->pool,
258 CONFIG_IIO_CONSUMERS_PER_TRIGGER,
259 ilog2(1));
260 if (ret < 0)
261 return ret;
262 }
263
264 return ret + trig->subirq_base;
265 }
266
iio_trigger_put_irq(struct iio_trigger * trig,int irq)267 static void iio_trigger_put_irq(struct iio_trigger *trig, int irq)
268 {
269 guard(mutex)(&trig->pool_lock);
270 clear_bit(irq - trig->subirq_base, trig->pool);
271 }
272
273 /* Complexity in here. With certain triggers (datardy) an acknowledgement
274 * may be needed if the pollfuncs do not include the data read for the
275 * triggering device.
276 * This is not currently handled. Alternative of not enabling trigger unless
277 * the relevant function is in there may be the best option.
278 */
279 /* Worth protecting against double additions? */
iio_trigger_attach_poll_func(struct iio_trigger * trig,struct iio_poll_func * pf)280 int iio_trigger_attach_poll_func(struct iio_trigger *trig,
281 struct iio_poll_func *pf)
282 {
283 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(pf->indio_dev);
284 bool notinuse =
285 bitmap_empty(trig->pool, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
286 int ret = 0;
287
288 /* Prevent the module from being removed whilst attached to a trigger */
289 __module_get(iio_dev_opaque->driver_module);
290
291 /* Get irq number */
292 pf->irq = iio_trigger_get_irq(trig);
293 if (pf->irq < 0) {
294 pr_err("Could not find an available irq for trigger %s, CONFIG_IIO_CONSUMERS_PER_TRIGGER=%d limit might be exceeded\n",
295 trig->name, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
296 goto out_put_module;
297 }
298
299 /* Request irq */
300 ret = request_threaded_irq(pf->irq, pf->h, pf->thread,
301 pf->type, pf->name,
302 pf);
303 if (ret < 0)
304 goto out_put_irq;
305
306 /* Enable trigger in driver */
307 if (trig->ops && trig->ops->set_trigger_state && notinuse) {
308 ret = trig->ops->set_trigger_state(trig, true);
309 if (ret)
310 goto out_free_irq;
311 }
312
313 /*
314 * Check if we just registered to our own trigger: we determine that
315 * this is the case if the IIO device and the trigger device share the
316 * same parent device.
317 */
318 if (!iio_validate_own_trigger(pf->indio_dev, trig))
319 trig->attached_own_device = true;
320
321 return ret;
322
323 out_free_irq:
324 free_irq(pf->irq, pf);
325 out_put_irq:
326 iio_trigger_put_irq(trig, pf->irq);
327 out_put_module:
328 module_put(iio_dev_opaque->driver_module);
329 return ret;
330 }
331
iio_trigger_detach_poll_func(struct iio_trigger * trig,struct iio_poll_func * pf)332 int iio_trigger_detach_poll_func(struct iio_trigger *trig,
333 struct iio_poll_func *pf)
334 {
335 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(pf->indio_dev);
336 bool no_other_users =
337 bitmap_weight(trig->pool, CONFIG_IIO_CONSUMERS_PER_TRIGGER) == 1;
338 int ret = 0;
339
340 if (trig->ops && trig->ops->set_trigger_state && no_other_users) {
341 ret = trig->ops->set_trigger_state(trig, false);
342 if (ret)
343 return ret;
344 }
345 if (pf->indio_dev->dev.parent == trig->dev.parent)
346 trig->attached_own_device = false;
347 iio_trigger_put_irq(trig, pf->irq);
348 free_irq(pf->irq, pf);
349 module_put(iio_dev_opaque->driver_module);
350 pf->irq = 0;
351
352 return ret;
353 }
354
iio_pollfunc_store_time(int irq,void * p)355 irqreturn_t iio_pollfunc_store_time(int irq, void *p)
356 {
357 struct iio_poll_func *pf = p;
358
359 pf->timestamp = iio_get_time_ns(pf->indio_dev);
360 return IRQ_WAKE_THREAD;
361 }
362 EXPORT_SYMBOL(iio_pollfunc_store_time);
363
364 struct iio_poll_func
iio_alloc_pollfunc(irqreturn_t (* h)(int irq,void * p),irqreturn_t (* thread)(int irq,void * p),int type,struct iio_dev * indio_dev,const char * fmt,...)365 *iio_alloc_pollfunc(irqreturn_t (*h)(int irq, void *p),
366 irqreturn_t (*thread)(int irq, void *p),
367 int type,
368 struct iio_dev *indio_dev,
369 const char *fmt,
370 ...)
371 {
372 va_list vargs;
373 struct iio_poll_func *pf;
374
375 pf = kmalloc(sizeof(*pf), GFP_KERNEL);
376 if (!pf)
377 return NULL;
378 va_start(vargs, fmt);
379 pf->name = kvasprintf(GFP_KERNEL, fmt, vargs);
380 va_end(vargs);
381 if (pf->name == NULL) {
382 kfree(pf);
383 return NULL;
384 }
385 pf->h = h;
386 pf->thread = thread;
387 pf->type = type;
388 pf->indio_dev = indio_dev;
389
390 return pf;
391 }
392 EXPORT_SYMBOL_GPL(iio_alloc_pollfunc);
393
iio_dealloc_pollfunc(struct iio_poll_func * pf)394 void iio_dealloc_pollfunc(struct iio_poll_func *pf)
395 {
396 kfree(pf->name);
397 kfree(pf);
398 }
399 EXPORT_SYMBOL_GPL(iio_dealloc_pollfunc);
400
401 /**
402 * current_trigger_show() - trigger consumer sysfs query current trigger
403 * @dev: device associated with an industrial I/O device
404 * @attr: pointer to the device_attribute structure that
405 * is being processed
406 * @buf: buffer where the current trigger name will be printed into
407 *
408 * For trigger consumers the current_trigger interface allows the trigger
409 * used by the device to be queried.
410 *
411 * Return: a negative number on failure, the number of characters written
412 * on success or 0 if no trigger is available
413 */
current_trigger_show(struct device * dev,struct device_attribute * attr,char * buf)414 static ssize_t current_trigger_show(struct device *dev,
415 struct device_attribute *attr, char *buf)
416 {
417 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
418
419 if (indio_dev->trig)
420 return sysfs_emit(buf, "%s\n", indio_dev->trig->name);
421 return 0;
422 }
423
424 /**
425 * current_trigger_store() - trigger consumer sysfs set current trigger
426 * @dev: device associated with an industrial I/O device
427 * @attr: device attribute that is being processed
428 * @buf: string buffer that holds the name of the trigger
429 * @len: length of the trigger name held by buf
430 *
431 * For trigger consumers the current_trigger interface allows the trigger
432 * used for this device to be specified at run time based on the trigger's
433 * name.
434 *
435 * Return: negative error code on failure or length of the buffer
436 * on success
437 */
current_trigger_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)438 static ssize_t current_trigger_store(struct device *dev,
439 struct device_attribute *attr,
440 const char *buf, size_t len)
441 {
442 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
443 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
444 struct iio_trigger *oldtrig = indio_dev->trig;
445 struct iio_trigger *trig;
446 int ret;
447
448 scoped_guard(mutex, &iio_dev_opaque->mlock) {
449 if (iio_dev_opaque->currentmode == INDIO_BUFFER_TRIGGERED)
450 return -EBUSY;
451 if (iio_dev_opaque->trig_readonly)
452 return -EPERM;
453 }
454
455 trig = iio_trigger_acquire_by_name(buf);
456 if (oldtrig == trig) {
457 ret = len;
458 goto out_trigger_put;
459 }
460
461 if (trig && indio_dev->info->validate_trigger) {
462 ret = indio_dev->info->validate_trigger(indio_dev, trig);
463 if (ret)
464 goto out_trigger_put;
465 }
466
467 if (trig && trig->ops && trig->ops->validate_device) {
468 ret = trig->ops->validate_device(trig, indio_dev);
469 if (ret)
470 goto out_trigger_put;
471 }
472
473 indio_dev->trig = trig;
474
475 if (oldtrig) {
476 if (indio_dev->modes & INDIO_EVENT_TRIGGERED)
477 iio_trigger_detach_poll_func(oldtrig,
478 indio_dev->pollfunc_event);
479 iio_trigger_put(oldtrig);
480 }
481 if (indio_dev->trig) {
482 if (indio_dev->modes & INDIO_EVENT_TRIGGERED)
483 iio_trigger_attach_poll_func(indio_dev->trig,
484 indio_dev->pollfunc_event);
485 }
486
487 return len;
488
489 out_trigger_put:
490 if (trig)
491 iio_trigger_put(trig);
492 return ret;
493 }
494
495 static DEVICE_ATTR_RW(current_trigger);
496
497 static struct attribute *iio_trigger_consumer_attrs[] = {
498 &dev_attr_current_trigger.attr,
499 NULL,
500 };
501
502 static const struct attribute_group iio_trigger_consumer_attr_group = {
503 .name = "trigger",
504 .attrs = iio_trigger_consumer_attrs,
505 };
506
iio_trig_release(struct device * device)507 static void iio_trig_release(struct device *device)
508 {
509 struct iio_trigger *trig = to_iio_trigger(device);
510 int i;
511
512 if (trig->subirq_base) {
513 for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
514 irq_modify_status(trig->subirq_base + i,
515 IRQ_NOAUTOEN,
516 IRQ_NOREQUEST | IRQ_NOPROBE);
517 irq_set_chip(trig->subirq_base + i,
518 NULL);
519 irq_set_handler(trig->subirq_base + i,
520 NULL);
521 }
522
523 irq_free_descs(trig->subirq_base,
524 CONFIG_IIO_CONSUMERS_PER_TRIGGER);
525 }
526 kfree(trig->name);
527 kfree(trig);
528 }
529
530 static const struct device_type iio_trig_type = {
531 .release = iio_trig_release,
532 .groups = iio_trig_dev_groups,
533 };
534
iio_trig_subirqmask(struct irq_data * d)535 static void iio_trig_subirqmask(struct irq_data *d)
536 {
537 struct irq_chip *chip = irq_data_get_irq_chip(d);
538 struct iio_trigger *trig = container_of(chip, struct iio_trigger, subirq_chip);
539
540 trig->subirqs[d->irq - trig->subirq_base].enabled = false;
541 }
542
iio_trig_subirqunmask(struct irq_data * d)543 static void iio_trig_subirqunmask(struct irq_data *d)
544 {
545 struct irq_chip *chip = irq_data_get_irq_chip(d);
546 struct iio_trigger *trig = container_of(chip, struct iio_trigger, subirq_chip);
547
548 trig->subirqs[d->irq - trig->subirq_base].enabled = true;
549 }
550
551 static __printf(3, 0)
viio_trigger_alloc(struct device * parent,struct module * this_mod,const char * fmt,va_list vargs)552 struct iio_trigger *viio_trigger_alloc(struct device *parent,
553 struct module *this_mod,
554 const char *fmt,
555 va_list vargs)
556 {
557 struct iio_trigger *trig;
558 int i;
559
560 trig = kzalloc(sizeof(*trig), GFP_KERNEL);
561 if (!trig)
562 return NULL;
563
564 trig->dev.parent = parent;
565 trig->dev.type = &iio_trig_type;
566 trig->dev.bus = &iio_bus_type;
567 device_initialize(&trig->dev);
568 INIT_WORK(&trig->reenable_work, iio_reenable_work_fn);
569
570 mutex_init(&trig->pool_lock);
571 trig->subirq_base = irq_alloc_descs(-1, 0,
572 CONFIG_IIO_CONSUMERS_PER_TRIGGER,
573 0);
574 if (trig->subirq_base < 0)
575 goto free_trig;
576
577 trig->name = kvasprintf(GFP_KERNEL, fmt, vargs);
578 if (trig->name == NULL)
579 goto free_descs;
580
581 INIT_LIST_HEAD(&trig->list);
582
583 trig->owner = this_mod;
584
585 trig->subirq_chip.name = trig->name;
586 trig->subirq_chip.irq_mask = &iio_trig_subirqmask;
587 trig->subirq_chip.irq_unmask = &iio_trig_subirqunmask;
588 for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
589 irq_set_chip(trig->subirq_base + i, &trig->subirq_chip);
590 irq_set_handler(trig->subirq_base + i, &handle_simple_irq);
591 irq_modify_status(trig->subirq_base + i,
592 IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
593 }
594
595 return trig;
596
597 free_descs:
598 irq_free_descs(trig->subirq_base, CONFIG_IIO_CONSUMERS_PER_TRIGGER);
599 free_trig:
600 kfree(trig);
601 return NULL;
602 }
603
604 /**
605 * __iio_trigger_alloc - Allocate a trigger
606 * @parent: Device to allocate iio_trigger for
607 * @this_mod: module allocating the trigger
608 * @fmt: trigger name format. If it includes format
609 * specifiers, the additional arguments following
610 * format are formatted and inserted in the resulting
611 * string replacing their respective specifiers.
612 * RETURNS:
613 * Pointer to allocated iio_trigger on success, NULL on failure.
614 */
__iio_trigger_alloc(struct device * parent,struct module * this_mod,const char * fmt,...)615 struct iio_trigger *__iio_trigger_alloc(struct device *parent,
616 struct module *this_mod,
617 const char *fmt, ...)
618 {
619 struct iio_trigger *trig;
620 va_list vargs;
621
622 va_start(vargs, fmt);
623 trig = viio_trigger_alloc(parent, this_mod, fmt, vargs);
624 va_end(vargs);
625
626 return trig;
627 }
628 EXPORT_SYMBOL(__iio_trigger_alloc);
629
iio_trigger_free(struct iio_trigger * trig)630 void iio_trigger_free(struct iio_trigger *trig)
631 {
632 if (trig)
633 put_device(&trig->dev);
634 }
635 EXPORT_SYMBOL(iio_trigger_free);
636
devm_iio_trigger_release(struct device * dev,void * res)637 static void devm_iio_trigger_release(struct device *dev, void *res)
638 {
639 iio_trigger_free(*(struct iio_trigger **)res);
640 }
641
642 /**
643 * __devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc()
644 * Managed iio_trigger_alloc. iio_trigger allocated with this function is
645 * automatically freed on driver detach.
646 * @parent: Device to allocate iio_trigger for
647 * @this_mod: module allocating the trigger
648 * @fmt: trigger name format. If it includes format
649 * specifiers, the additional arguments following
650 * format are formatted and inserted in the resulting
651 * string replacing their respective specifiers.
652 *
653 *
654 * RETURNS:
655 * Pointer to allocated iio_trigger on success, NULL on failure.
656 */
__devm_iio_trigger_alloc(struct device * parent,struct module * this_mod,const char * fmt,...)657 struct iio_trigger *__devm_iio_trigger_alloc(struct device *parent,
658 struct module *this_mod,
659 const char *fmt, ...)
660 {
661 struct iio_trigger **ptr, *trig;
662 va_list vargs;
663
664 ptr = devres_alloc(devm_iio_trigger_release, sizeof(*ptr),
665 GFP_KERNEL);
666 if (!ptr)
667 return NULL;
668
669 /* use raw alloc_dr for kmalloc caller tracing */
670 va_start(vargs, fmt);
671 trig = viio_trigger_alloc(parent, this_mod, fmt, vargs);
672 va_end(vargs);
673 if (trig) {
674 *ptr = trig;
675 devres_add(parent, ptr);
676 } else {
677 devres_free(ptr);
678 }
679
680 return trig;
681 }
682 EXPORT_SYMBOL_GPL(__devm_iio_trigger_alloc);
683
devm_iio_trigger_unreg(void * trigger_info)684 static void devm_iio_trigger_unreg(void *trigger_info)
685 {
686 iio_trigger_unregister(trigger_info);
687 }
688
689 /**
690 * devm_iio_trigger_register - Resource-managed iio_trigger_register()
691 * @dev: device this trigger was allocated for
692 * @trig_info: trigger to register
693 *
694 * Managed iio_trigger_register(). The IIO trigger registered with this
695 * function is automatically unregistered on driver detach. This function
696 * calls iio_trigger_register() internally. Refer to that function for more
697 * information.
698 *
699 * RETURNS:
700 * 0 on success, negative error number on failure.
701 */
devm_iio_trigger_register(struct device * dev,struct iio_trigger * trig_info)702 int devm_iio_trigger_register(struct device *dev,
703 struct iio_trigger *trig_info)
704 {
705 int ret;
706
707 ret = iio_trigger_register(trig_info);
708 if (ret)
709 return ret;
710
711 return devm_add_action_or_reset(dev, devm_iio_trigger_unreg, trig_info);
712 }
713 EXPORT_SYMBOL_GPL(devm_iio_trigger_register);
714
iio_trigger_using_own(struct iio_dev * indio_dev)715 bool iio_trigger_using_own(struct iio_dev *indio_dev)
716 {
717 return indio_dev->trig->attached_own_device;
718 }
719 EXPORT_SYMBOL(iio_trigger_using_own);
720
721 /**
722 * iio_validate_own_trigger - Check if a trigger and IIO device belong to
723 * the same device
724 * @idev: the IIO device to check
725 * @trig: the IIO trigger to check
726 *
727 * This function can be used as the validate_trigger callback for triggers that
728 * can only be attached to their own device.
729 *
730 * Return: 0 if both the trigger and the IIO device belong to the same
731 * device, -EINVAL otherwise.
732 */
iio_validate_own_trigger(struct iio_dev * idev,struct iio_trigger * trig)733 int iio_validate_own_trigger(struct iio_dev *idev, struct iio_trigger *trig)
734 {
735 if (idev->dev.parent != trig->dev.parent)
736 return -EINVAL;
737 return 0;
738 }
739 EXPORT_SYMBOL_GPL(iio_validate_own_trigger);
740
741 /**
742 * iio_trigger_validate_own_device - Check if a trigger and IIO device belong to
743 * the same device
744 * @trig: The IIO trigger to check
745 * @indio_dev: the IIO device to check
746 *
747 * This function can be used as the validate_device callback for triggers that
748 * can only be attached to their own device.
749 *
750 * Return: 0 if both the trigger and the IIO device belong to the same
751 * device, -EINVAL otherwise.
752 */
iio_trigger_validate_own_device(struct iio_trigger * trig,struct iio_dev * indio_dev)753 int iio_trigger_validate_own_device(struct iio_trigger *trig,
754 struct iio_dev *indio_dev)
755 {
756 if (indio_dev->dev.parent != trig->dev.parent)
757 return -EINVAL;
758 return 0;
759 }
760 EXPORT_SYMBOL(iio_trigger_validate_own_device);
761
iio_device_register_trigger_consumer(struct iio_dev * indio_dev)762 int iio_device_register_trigger_consumer(struct iio_dev *indio_dev)
763 {
764 return iio_device_register_sysfs_group(indio_dev,
765 &iio_trigger_consumer_attr_group);
766 }
767
iio_device_unregister_trigger_consumer(struct iio_dev * indio_dev)768 void iio_device_unregister_trigger_consumer(struct iio_dev *indio_dev)
769 {
770 /* Clean up an associated but not attached trigger reference */
771 if (indio_dev->trig)
772 iio_trigger_put(indio_dev->trig);
773 }
774
iio_device_suspend_triggering(struct iio_dev * indio_dev)775 int iio_device_suspend_triggering(struct iio_dev *indio_dev)
776 {
777 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
778
779 guard(mutex)(&iio_dev_opaque->mlock);
780
781 if ((indio_dev->pollfunc) && (indio_dev->pollfunc->irq > 0))
782 disable_irq(indio_dev->pollfunc->irq);
783
784 return 0;
785 }
786 EXPORT_SYMBOL(iio_device_suspend_triggering);
787
iio_device_resume_triggering(struct iio_dev * indio_dev)788 int iio_device_resume_triggering(struct iio_dev *indio_dev)
789 {
790 struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
791
792 guard(mutex)(&iio_dev_opaque->mlock);
793
794 if ((indio_dev->pollfunc) && (indio_dev->pollfunc->irq > 0))
795 enable_irq(indio_dev->pollfunc->irq);
796
797 return 0;
798 }
799 EXPORT_SYMBOL(iio_device_resume_triggering);
800