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