drivers/iio/industrialio-trigger.c

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

DEFINITIONS
