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/interrupt.h> 20#include <linux/poll.h> 21#include <linux/sched.h> 22#include <linux/wait.h> 23#include <linux/cdev.h> 24#include <linux/slab.h> 25#include "iio.h" 26#include "trigger_consumer.h" 27 28#define IIO_ID_PREFIX "device" 29#define IIO_ID_FORMAT IIO_ID_PREFIX "%d" 30 31/* IDR to assign each registered device a unique id*/ 32static DEFINE_IDR(iio_idr); 33/* IDR to allocate character device minor numbers */ 34static DEFINE_IDR(iio_chrdev_idr); 35/* Lock used to protect both of the above */ 36static DEFINE_SPINLOCK(iio_idr_lock); 37 38dev_t iio_devt; 39EXPORT_SYMBOL(iio_devt); 40 41#define IIO_DEV_MAX 256 42struct bus_type iio_bus_type = { 43 .name = "iio", 44}; 45EXPORT_SYMBOL(iio_bus_type); 46 47void __iio_change_event(struct iio_detected_event_list *ev, 48 int ev_code, 49 s64 timestamp) 50{ 51 ev->ev.id = ev_code; 52 ev->ev.timestamp = timestamp; 53} 54EXPORT_SYMBOL(__iio_change_event); 55 56/* Used both in the interrupt line put events and the ring buffer ones */ 57 58/* Note that in it's current form someone has to be listening before events 59 * are queued. Hence a client MUST open the chrdev before the ring buffer is 60 * switched on. 61 */ 62 int __iio_push_event(struct iio_event_interface *ev_int, 63 int ev_code, 64 s64 timestamp, 65 struct iio_shared_ev_pointer * 66 shared_pointer_p) 67{ 68 struct iio_detected_event_list *ev; 69 int ret = 0; 70 71 /* Does anyone care? */ 72 mutex_lock(&ev_int->event_list_lock); 73 if (test_bit(IIO_BUSY_BIT_POS, &ev_int->handler.flags)) { 74 if (ev_int->current_events == ev_int->max_events) { 75 mutex_unlock(&ev_int->event_list_lock); 76 return 0; 77 } 78 ev = kmalloc(sizeof(*ev), GFP_KERNEL); 79 if (ev == NULL) { 80 ret = -ENOMEM; 81 mutex_unlock(&ev_int->event_list_lock); 82 goto error_ret; 83 } 84 ev->ev.id = ev_code; 85 ev->ev.timestamp = timestamp; 86 ev->shared_pointer = shared_pointer_p; 87 if (ev->shared_pointer) 88 shared_pointer_p->ev_p = ev; 89 90 list_add_tail(&ev->list, &ev_int->det_events.list); 91 ev_int->current_events++; 92 mutex_unlock(&ev_int->event_list_lock); 93 wake_up_interruptible(&ev_int->wait); 94 } else 95 mutex_unlock(&ev_int->event_list_lock); 96 97error_ret: 98 return ret; 99} 100EXPORT_SYMBOL(__iio_push_event); 101 102int iio_push_event(struct iio_dev *dev_info, 103 int ev_line, 104 int ev_code, 105 s64 timestamp) 106{ 107 return __iio_push_event(&dev_info->event_interfaces[ev_line], 108 ev_code, timestamp, NULL); 109} 110EXPORT_SYMBOL(iio_push_event); 111 112/* Generic interrupt line interrupt handler */ 113static irqreturn_t iio_interrupt_handler(int irq, void *_int_info) 114{ 115 struct iio_interrupt *int_info = _int_info; 116 struct iio_dev *dev_info = int_info->dev_info; 117 struct iio_event_handler_list *p; 118 s64 time_ns; 119 unsigned long flags; 120 121 spin_lock_irqsave(&int_info->ev_list_lock, flags); 122 if (list_empty(&int_info->ev_list)) { 123 spin_unlock_irqrestore(&int_info->ev_list_lock, flags); 124 return IRQ_NONE; 125 } 126 127 time_ns = iio_get_time_ns(); 128 /* detect single element list*/ 129 if (list_is_singular(&int_info->ev_list)) { 130 disable_irq_nosync(irq); 131 p = list_first_entry(&int_info->ev_list, 132 struct iio_event_handler_list, 133 list); 134 /* single event handler - maybe shared */ 135 p->handler(dev_info, 1, time_ns, !(p->refcount > 1)); 136 } else 137 list_for_each_entry(p, &int_info->ev_list, list) { 138 disable_irq_nosync(irq); 139 p->handler(dev_info, 1, time_ns, 0); 140 } 141 spin_unlock_irqrestore(&int_info->ev_list_lock, flags); 142 143 return IRQ_HANDLED; 144} 145 146static struct iio_interrupt *iio_allocate_interrupt(void) 147{ 148 struct iio_interrupt *i = kmalloc(sizeof *i, GFP_KERNEL); 149 if (i) { 150 spin_lock_init(&i->ev_list_lock); 151 INIT_LIST_HEAD(&i->ev_list); 152 } 153 return i; 154} 155 156/* Confirming the validity of supplied irq is left to drivers.*/ 157int iio_register_interrupt_line(unsigned int irq, 158 struct iio_dev *dev_info, 159 int line_number, 160 unsigned long type, 161 const char *name) 162{ 163 int ret; 164 165 dev_info->interrupts[line_number] = iio_allocate_interrupt(); 166 if (dev_info->interrupts[line_number] == NULL) { 167 ret = -ENOMEM; 168 goto error_ret; 169 } 170 dev_info->interrupts[line_number]->line_number = line_number; 171 dev_info->interrupts[line_number]->irq = irq; 172 dev_info->interrupts[line_number]->dev_info = dev_info; 173 174 /* Possibly only request on demand? 175 * Can see this may complicate the handling of interrupts. 176 * However, with this approach we might end up handling lots of 177 * events no-one cares about.*/ 178 ret = request_irq(irq, 179 &iio_interrupt_handler, 180 type, 181 name, 182 dev_info->interrupts[line_number]); 183 184error_ret: 185 return ret; 186} 187EXPORT_SYMBOL(iio_register_interrupt_line); 188 189/* This turns up an awful lot */ 190ssize_t iio_read_const_attr(struct device *dev, 191 struct device_attribute *attr, 192 char *buf) 193{ 194 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string); 195} 196EXPORT_SYMBOL(iio_read_const_attr); 197 198/* Before this runs the interrupt generator must have been disabled */ 199void iio_unregister_interrupt_line(struct iio_dev *dev_info, int line_number) 200{ 201 /* make sure the interrupt handlers are all done */ 202 flush_scheduled_work(); 203 free_irq(dev_info->interrupts[line_number]->irq, 204 dev_info->interrupts[line_number]); 205 kfree(dev_info->interrupts[line_number]); 206} 207EXPORT_SYMBOL(iio_unregister_interrupt_line); 208 209/* Reference counted add and remove */ 210void iio_add_event_to_list(struct iio_event_handler_list *el, 211 struct list_head *head) 212{ 213 unsigned long flags; 214 struct iio_interrupt *inter = to_iio_interrupt(head); 215 216 /* take mutex to protect this element */ 217 mutex_lock(&el->exist_lock); 218 if (el->refcount == 0) { 219 /* Take the event list spin lock */ 220 spin_lock_irqsave(&inter->ev_list_lock, flags); 221 list_add(&el->list, head); 222 spin_unlock_irqrestore(&inter->ev_list_lock, flags); 223 } 224 el->refcount++; 225 mutex_unlock(&el->exist_lock); 226} 227EXPORT_SYMBOL(iio_add_event_to_list); 228 229void iio_remove_event_from_list(struct iio_event_handler_list *el, 230 struct list_head *head) 231{ 232 unsigned long flags; 233 struct iio_interrupt *inter = to_iio_interrupt(head); 234 235 mutex_lock(&el->exist_lock); 236 el->refcount--; 237 if (el->refcount == 0) { 238 /* Take the event list spin lock */ 239 spin_lock_irqsave(&inter->ev_list_lock, flags); 240 list_del_init(&el->list); 241 spin_unlock_irqrestore(&inter->ev_list_lock, flags); 242 } 243 mutex_unlock(&el->exist_lock); 244} 245EXPORT_SYMBOL(iio_remove_event_from_list); 246 247static ssize_t iio_event_chrdev_read(struct file *filep, 248 char __user *buf, 249 size_t count, 250 loff_t *f_ps) 251{ 252 struct iio_event_interface *ev_int = filep->private_data; 253 struct iio_detected_event_list *el; 254 int ret; 255 size_t len; 256 257 mutex_lock(&ev_int->event_list_lock); 258 if (list_empty(&ev_int->det_events.list)) { 259 if (filep->f_flags & O_NONBLOCK) { 260 ret = -EAGAIN; 261 goto error_mutex_unlock; 262 } 263 mutex_unlock(&ev_int->event_list_lock); 264 /* Blocking on device; waiting for something to be there */ 265 ret = wait_event_interruptible(ev_int->wait, 266 !list_empty(&ev_int 267 ->det_events.list)); 268 if (ret) 269 goto error_ret; 270 /* Single access device so noone else can get the data */ 271 mutex_lock(&ev_int->event_list_lock); 272 } 273 274 el = list_first_entry(&ev_int->det_events.list, 275 struct iio_detected_event_list, 276 list); 277 len = sizeof el->ev; 278 if (copy_to_user(buf, &(el->ev), len)) { 279 ret = -EFAULT; 280 goto error_mutex_unlock; 281 } 282 list_del(&el->list); 283 ev_int->current_events--; 284 mutex_unlock(&ev_int->event_list_lock); 285 /* 286 * Possible concurency issue if an update of this event is on its way 287 * through. May lead to new event being removed whilst the reported 288 * event was the unescalated event. In typical use case this is not a 289 * problem as userspace will say read half the buffer due to a 50% 290 * full event which would make the correct 100% full incorrect anyway. 291 */ 292 if (el->shared_pointer) { 293 spin_lock(&el->shared_pointer->lock); 294 (el->shared_pointer->ev_p) = NULL; 295 spin_unlock(&el->shared_pointer->lock); 296 } 297 kfree(el); 298 299 return len; 300 301error_mutex_unlock: 302 mutex_unlock(&ev_int->event_list_lock); 303error_ret: 304 305 return ret; 306} 307 308static int iio_event_chrdev_release(struct inode *inode, struct file *filep) 309{ 310 struct iio_handler *hand = iio_cdev_to_handler(inode->i_cdev); 311 struct iio_event_interface *ev_int = hand->private; 312 struct iio_detected_event_list *el, *t; 313 314 mutex_lock(&ev_int->event_list_lock); 315 clear_bit(IIO_BUSY_BIT_POS, &ev_int->handler.flags); 316 /* 317 * In order to maintain a clean state for reopening, 318 * clear out any awaiting events. The mask will prevent 319 * any new __iio_push_event calls running. 320 */ 321 list_for_each_entry_safe(el, t, &ev_int->det_events.list, list) { 322 list_del(&el->list); 323 kfree(el); 324 } 325 mutex_unlock(&ev_int->event_list_lock); 326 327 return 0; 328} 329 330static int iio_event_chrdev_open(struct inode *inode, struct file *filep) 331{ 332 struct iio_handler *hand = iio_cdev_to_handler(inode->i_cdev); 333 struct iio_event_interface *ev_int = hand->private; 334 335 mutex_lock(&ev_int->event_list_lock); 336 if (test_and_set_bit(IIO_BUSY_BIT_POS, &hand->flags)) { 337 fops_put(filep->f_op); 338 mutex_unlock(&ev_int->event_list_lock); 339 return -EBUSY; 340 } 341 filep->private_data = hand->private; 342 mutex_unlock(&ev_int->event_list_lock); 343 344 return 0; 345} 346 347static const struct file_operations iio_event_chrdev_fileops = { 348 .read = iio_event_chrdev_read, 349 .release = iio_event_chrdev_release, 350 .open = iio_event_chrdev_open, 351 .owner = THIS_MODULE, 352}; 353 354static void iio_event_dev_release(struct device *dev) 355{ 356 struct iio_event_interface *ev_int 357 = container_of(dev, struct iio_event_interface, dev); 358 cdev_del(&ev_int->handler.chrdev); 359 iio_device_free_chrdev_minor(MINOR(dev->devt)); 360}; 361 362static struct device_type iio_event_type = { 363 .release = iio_event_dev_release, 364}; 365 366int iio_device_get_chrdev_minor(void) 367{ 368 int ret, val; 369 370idr_again: 371 if (unlikely(idr_pre_get(&iio_chrdev_idr, GFP_KERNEL) == 0)) 372 return -ENOMEM; 373 spin_lock(&iio_idr_lock); 374 ret = idr_get_new(&iio_chrdev_idr, NULL, &val); 375 spin_unlock(&iio_idr_lock); 376 if (unlikely(ret == -EAGAIN)) 377 goto idr_again; 378 else if (unlikely(ret)) 379 return ret; 380 if (val > IIO_DEV_MAX) 381 return -ENOMEM; 382 return val; 383} 384 385void iio_device_free_chrdev_minor(int val) 386{ 387 spin_lock(&iio_idr_lock); 388 idr_remove(&iio_chrdev_idr, val); 389 spin_unlock(&iio_idr_lock); 390} 391 392int iio_setup_ev_int(struct iio_event_interface *ev_int, 393 const char *name, 394 struct module *owner, 395 struct device *dev) 396{ 397 int ret, minor; 398 399 ev_int->dev.bus = &iio_bus_type; 400 ev_int->dev.parent = dev; 401 ev_int->dev.type = &iio_event_type; 402 device_initialize(&ev_int->dev); 403 404 minor = iio_device_get_chrdev_minor(); 405 if (minor < 0) { 406 ret = minor; 407 goto error_device_put; 408 } 409 ev_int->dev.devt = MKDEV(MAJOR(iio_devt), minor); 410 dev_set_name(&ev_int->dev, "%s", name); 411 412 ret = device_add(&ev_int->dev); 413 if (ret) 414 goto error_free_minor; 415 416 cdev_init(&ev_int->handler.chrdev, &iio_event_chrdev_fileops); 417 ev_int->handler.chrdev.owner = owner; 418 419 mutex_init(&ev_int->event_list_lock); 420 /* discussion point - make this variable? */ 421 ev_int->max_events = 10; 422 ev_int->current_events = 0; 423 INIT_LIST_HEAD(&ev_int->det_events.list); 424 init_waitqueue_head(&ev_int->wait); 425 ev_int->handler.private = ev_int; 426 ev_int->handler.flags = 0; 427 428 ret = cdev_add(&ev_int->handler.chrdev, ev_int->dev.devt, 1); 429 if (ret) 430 goto error_unreg_device; 431 432 return 0; 433 434error_unreg_device: 435 device_unregister(&ev_int->dev); 436error_free_minor: 437 iio_device_free_chrdev_minor(minor); 438error_device_put: 439 put_device(&ev_int->dev); 440 441 return ret; 442} 443 444void iio_free_ev_int(struct iio_event_interface *ev_int) 445{ 446 device_unregister(&ev_int->dev); 447 put_device(&ev_int->dev); 448} 449 450static int __init iio_dev_init(void) 451{ 452 int err; 453 454 err = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio"); 455 if (err < 0) 456 printk(KERN_ERR "%s: failed to allocate char dev region\n", 457 __FILE__); 458 459 return err; 460} 461 462static void __exit iio_dev_exit(void) 463{ 464 if (iio_devt) 465 unregister_chrdev_region(iio_devt, IIO_DEV_MAX); 466} 467 468static int __init iio_init(void) 469{ 470 int ret; 471 472 /* Register sysfs bus */ 473 ret = bus_register(&iio_bus_type); 474 if (ret < 0) { 475 printk(KERN_ERR 476 "%s could not register bus type\n", 477 __FILE__); 478 goto error_nothing; 479 } 480 481 ret = iio_dev_init(); 482 if (ret < 0) 483 goto error_unregister_bus_type; 484 485 return 0; 486 487error_unregister_bus_type: 488 bus_unregister(&iio_bus_type); 489error_nothing: 490 return ret; 491} 492 493static void __exit iio_exit(void) 494{ 495 iio_dev_exit(); 496 bus_unregister(&iio_bus_type); 497} 498 499static int iio_device_register_sysfs(struct iio_dev *dev_info) 500{ 501 int ret = 0; 502 503 ret = sysfs_create_group(&dev_info->dev.kobj, dev_info->attrs); 504 if (ret) { 505 dev_err(dev_info->dev.parent, 506 "Failed to register sysfs hooks\n"); 507 goto error_ret; 508 } 509 510 if (dev_info->scan_el_attrs) { 511 ret = sysfs_create_group(&dev_info->dev.kobj, 512 dev_info->scan_el_attrs); 513 if (ret) 514 dev_err(&dev_info->dev, 515 "Failed to add sysfs scan els\n"); 516 } 517 518error_ret: 519 return ret; 520} 521 522static void iio_device_unregister_sysfs(struct iio_dev *dev_info) 523{ 524 if (dev_info->scan_el_attrs) 525 sysfs_remove_group(&dev_info->dev.kobj, 526 dev_info->scan_el_attrs); 527 528 sysfs_remove_group(&dev_info->dev.kobj, dev_info->attrs); 529} 530 531/* Return a negative errno on failure */ 532int iio_get_new_idr_val(struct idr *this_idr) 533{ 534 int ret; 535 int val; 536 537idr_again: 538 if (unlikely(idr_pre_get(this_idr, GFP_KERNEL) == 0)) 539 return -ENOMEM; 540 541 spin_lock(&iio_idr_lock); 542 ret = idr_get_new(this_idr, NULL, &val); 543 spin_unlock(&iio_idr_lock); 544 if (unlikely(ret == -EAGAIN)) 545 goto idr_again; 546 else if (unlikely(ret)) 547 return ret; 548 549 return val; 550} 551EXPORT_SYMBOL(iio_get_new_idr_val); 552 553void iio_free_idr_val(struct idr *this_idr, int id) 554{ 555 spin_lock(&iio_idr_lock); 556 idr_remove(this_idr, id); 557 spin_unlock(&iio_idr_lock); 558} 559EXPORT_SYMBOL(iio_free_idr_val); 560 561static int iio_device_register_id(struct iio_dev *dev_info, 562 struct idr *this_idr) 563{ 564 565 dev_info->id = iio_get_new_idr_val(&iio_idr); 566 if (dev_info->id < 0) 567 return dev_info->id; 568 return 0; 569} 570 571static void iio_device_unregister_id(struct iio_dev *dev_info) 572{ 573 iio_free_idr_val(&iio_idr, dev_info->id); 574} 575 576static inline int __iio_add_event_config_attrs(struct iio_dev *dev_info, int i) 577{ 578 int ret; 579 /*p for adding, q for removing */ 580 struct attribute **attrp, **attrq; 581 582 if (dev_info->event_conf_attrs && dev_info->event_conf_attrs[i].attrs) { 583 attrp = dev_info->event_conf_attrs[i].attrs; 584 while (*attrp) { 585 ret = sysfs_add_file_to_group(&dev_info->dev.kobj, 586 *attrp, 587 dev_info 588 ->event_attrs[i].name); 589 if (ret) 590 goto error_ret; 591 attrp++; 592 } 593 } 594 return 0; 595 596error_ret: 597 attrq = dev_info->event_conf_attrs[i].attrs; 598 while (attrq != attrp) { 599 sysfs_remove_file_from_group(&dev_info->dev.kobj, 600 *attrq, 601 dev_info->event_attrs[i].name); 602 attrq++; 603 } 604 605 return ret; 606} 607 608static inline int __iio_remove_event_config_attrs(struct iio_dev *dev_info, 609 int i) 610{ 611 struct attribute **attrq; 612 613 if (dev_info->event_conf_attrs 614 && dev_info->event_conf_attrs[i].attrs) { 615 attrq = dev_info->event_conf_attrs[i].attrs; 616 while (*attrq) { 617 sysfs_remove_file_from_group(&dev_info->dev.kobj, 618 *attrq, 619 dev_info 620 ->event_attrs[i].name); 621 attrq++; 622 } 623 } 624 625 return 0; 626} 627 628static int iio_device_register_eventset(struct iio_dev *dev_info) 629{ 630 int ret = 0, i, j; 631 632 if (dev_info->num_interrupt_lines == 0) 633 return 0; 634 635 dev_info->event_interfaces = 636 kzalloc(sizeof(struct iio_event_interface) 637 *dev_info->num_interrupt_lines, 638 GFP_KERNEL); 639 if (dev_info->event_interfaces == NULL) { 640 ret = -ENOMEM; 641 goto error_ret; 642 } 643 644 dev_info->interrupts = kzalloc(sizeof(struct iio_interrupt *) 645 *dev_info->num_interrupt_lines, 646 GFP_KERNEL); 647 if (dev_info->interrupts == NULL) { 648 ret = -ENOMEM; 649 goto error_free_event_interfaces; 650 } 651 652 for (i = 0; i < dev_info->num_interrupt_lines; i++) { 653 dev_info->event_interfaces[i].owner = dev_info->driver_module; 654 655 snprintf(dev_info->event_interfaces[i]._name, 20, 656 "%s:event%d", 657 dev_name(&dev_info->dev), 658 i); 659 660 ret = iio_setup_ev_int(&dev_info->event_interfaces[i], 661 (const char *)(dev_info 662 ->event_interfaces[i] 663 ._name), 664 dev_info->driver_module, 665 &dev_info->dev); 666 if (ret) { 667 dev_err(&dev_info->dev, 668 "Could not get chrdev interface\n"); 669 goto error_free_setup_ev_ints; 670 } 671 672 dev_set_drvdata(&dev_info->event_interfaces[i].dev, 673 (void *)dev_info); 674 ret = sysfs_create_group(&dev_info 675 ->event_interfaces[i] 676 .dev.kobj, 677 &dev_info->event_attrs[i]); 678 679 if (ret) { 680 dev_err(&dev_info->dev, 681 "Failed to register sysfs for event attrs"); 682 goto error_remove_sysfs_interfaces; 683 } 684 } 685 686 for (i = 0; i < dev_info->num_interrupt_lines; i++) { 687 ret = __iio_add_event_config_attrs(dev_info, i); 688 if (ret) 689 goto error_unregister_config_attrs; 690 } 691 692 return 0; 693 694error_unregister_config_attrs: 695 for (j = 0; j < i; j++) 696 __iio_remove_event_config_attrs(dev_info, i); 697 i = dev_info->num_interrupt_lines - 1; 698error_remove_sysfs_interfaces: 699 for (j = 0; j < i; j++) 700 sysfs_remove_group(&dev_info 701 ->event_interfaces[j].dev.kobj, 702 &dev_info->event_attrs[j]); 703error_free_setup_ev_ints: 704 for (j = 0; j < i; j++) 705 iio_free_ev_int(&dev_info->event_interfaces[j]); 706 kfree(dev_info->interrupts); 707error_free_event_interfaces: 708 kfree(dev_info->event_interfaces); 709error_ret: 710 711 return ret; 712} 713 714static void iio_device_unregister_eventset(struct iio_dev *dev_info) 715{ 716 int i; 717 718 if (dev_info->num_interrupt_lines == 0) 719 return; 720 for (i = 0; i < dev_info->num_interrupt_lines; i++) 721 sysfs_remove_group(&dev_info 722 ->event_interfaces[i].dev.kobj, 723 &dev_info->event_attrs[i]); 724 725 for (i = 0; i < dev_info->num_interrupt_lines; i++) 726 iio_free_ev_int(&dev_info->event_interfaces[i]); 727 kfree(dev_info->interrupts); 728 kfree(dev_info->event_interfaces); 729} 730 731static void iio_dev_release(struct device *device) 732{ 733 struct iio_dev *dev = to_iio_dev(device); 734 735 iio_put(); 736 kfree(dev); 737} 738 739static struct device_type iio_dev_type = { 740 .name = "iio_device", 741 .release = iio_dev_release, 742}; 743 744struct iio_dev *iio_allocate_device(void) 745{ 746 struct iio_dev *dev = kzalloc(sizeof *dev, GFP_KERNEL); 747 748 if (dev) { 749 dev->dev.type = &iio_dev_type; 750 dev->dev.bus = &iio_bus_type; 751 device_initialize(&dev->dev); 752 dev_set_drvdata(&dev->dev, (void *)dev); 753 mutex_init(&dev->mlock); 754 iio_get(); 755 } 756 757 return dev; 758} 759EXPORT_SYMBOL(iio_allocate_device); 760 761void iio_free_device(struct iio_dev *dev) 762{ 763 if (dev) 764 iio_put_device(dev); 765} 766EXPORT_SYMBOL(iio_free_device); 767 768int iio_device_register(struct iio_dev *dev_info) 769{ 770 int ret; 771 772 ret = iio_device_register_id(dev_info, &iio_idr); 773 if (ret) { 774 dev_err(&dev_info->dev, "Failed to get id\n"); 775 goto error_ret; 776 } 777 dev_set_name(&dev_info->dev, "device%d", dev_info->id); 778 779 ret = device_add(&dev_info->dev); 780 if (ret) 781 goto error_free_idr; 782 ret = iio_device_register_sysfs(dev_info); 783 if (ret) { 784 dev_err(dev_info->dev.parent, 785 "Failed to register sysfs interfaces\n"); 786 goto error_del_device; 787 } 788 ret = iio_device_register_eventset(dev_info); 789 if (ret) { 790 dev_err(dev_info->dev.parent, 791 "Failed to register event set\n"); 792 goto error_free_sysfs; 793 } 794 if (dev_info->modes & INDIO_RING_TRIGGERED) 795 iio_device_register_trigger_consumer(dev_info); 796 797 return 0; 798 799error_free_sysfs: 800 iio_device_unregister_sysfs(dev_info); 801error_del_device: 802 device_del(&dev_info->dev); 803error_free_idr: 804 iio_device_unregister_id(dev_info); 805error_ret: 806 return ret; 807} 808EXPORT_SYMBOL(iio_device_register); 809 810void iio_device_unregister(struct iio_dev *dev_info) 811{ 812 if (dev_info->modes & INDIO_RING_TRIGGERED) 813 iio_device_unregister_trigger_consumer(dev_info); 814 iio_device_unregister_eventset(dev_info); 815 iio_device_unregister_sysfs(dev_info); 816 iio_device_unregister_id(dev_info); 817 device_unregister(&dev_info->dev); 818} 819EXPORT_SYMBOL(iio_device_unregister); 820 821void iio_put(void) 822{ 823 module_put(THIS_MODULE); 824} 825 826void iio_get(void) 827{ 828 __module_get(THIS_MODULE); 829} 830 831subsys_initcall(iio_init); 832module_exit(iio_exit); 833 834MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>"); 835MODULE_DESCRIPTION("Industrial I/O core"); 836MODULE_LICENSE("GPL"); 837