1 /* 2 * The input core 3 * 4 * Copyright (c) 1999-2002 Vojtech Pavlik 5 */ 6 7 /* 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License version 2 as published by 10 * the Free Software Foundation. 11 */ 12 13 #include <linux/init.h> 14 #include <linux/input.h> 15 #include <linux/module.h> 16 #include <linux/random.h> 17 #include <linux/major.h> 18 #include <linux/proc_fs.h> 19 #include <linux/seq_file.h> 20 #include <linux/poll.h> 21 #include <linux/device.h> 22 #include <linux/mutex.h> 23 #include <linux/rcupdate.h> 24 #include <linux/smp_lock.h> 25 26 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>"); 27 MODULE_DESCRIPTION("Input core"); 28 MODULE_LICENSE("GPL"); 29 30 #define INPUT_DEVICES 256 31 32 static LIST_HEAD(input_dev_list); 33 static LIST_HEAD(input_handler_list); 34 35 /* 36 * input_mutex protects access to both input_dev_list and input_handler_list. 37 * This also causes input_[un]register_device and input_[un]register_handler 38 * be mutually exclusive which simplifies locking in drivers implementing 39 * input handlers. 40 */ 41 static DEFINE_MUTEX(input_mutex); 42 43 static struct input_handler *input_table[8]; 44 45 static inline int is_event_supported(unsigned int code, 46 unsigned long *bm, unsigned int max) 47 { 48 return code <= max && test_bit(code, bm); 49 } 50 51 static int input_defuzz_abs_event(int value, int old_val, int fuzz) 52 { 53 if (fuzz) { 54 if (value > old_val - fuzz / 2 && value < old_val + fuzz / 2) 55 return old_val; 56 57 if (value > old_val - fuzz && value < old_val + fuzz) 58 return (old_val * 3 + value) / 4; 59 60 if (value > old_val - fuzz * 2 && value < old_val + fuzz * 2) 61 return (old_val + value) / 2; 62 } 63 64 return value; 65 } 66 67 /* 68 * Pass event through all open handles. This function is called with 69 * dev->event_lock held and interrupts disabled. 70 */ 71 static void input_pass_event(struct input_dev *dev, 72 unsigned int type, unsigned int code, int value) 73 { 74 struct input_handle *handle; 75 76 rcu_read_lock(); 77 78 handle = rcu_dereference(dev->grab); 79 if (handle) 80 handle->handler->event(handle, type, code, value); 81 else 82 list_for_each_entry_rcu(handle, &dev->h_list, d_node) 83 if (handle->open) 84 handle->handler->event(handle, 85 type, code, value); 86 rcu_read_unlock(); 87 } 88 89 /* 90 * Generate software autorepeat event. Note that we take 91 * dev->event_lock here to avoid racing with input_event 92 * which may cause keys get "stuck". 93 */ 94 static void input_repeat_key(unsigned long data) 95 { 96 struct input_dev *dev = (void *) data; 97 unsigned long flags; 98 99 spin_lock_irqsave(&dev->event_lock, flags); 100 101 if (test_bit(dev->repeat_key, dev->key) && 102 is_event_supported(dev->repeat_key, dev->keybit, KEY_MAX)) { 103 104 input_pass_event(dev, EV_KEY, dev->repeat_key, 2); 105 106 if (dev->sync) { 107 /* 108 * Only send SYN_REPORT if we are not in a middle 109 * of driver parsing a new hardware packet. 110 * Otherwise assume that the driver will send 111 * SYN_REPORT once it's done. 112 */ 113 input_pass_event(dev, EV_SYN, SYN_REPORT, 1); 114 } 115 116 if (dev->rep[REP_PERIOD]) 117 mod_timer(&dev->timer, jiffies + 118 msecs_to_jiffies(dev->rep[REP_PERIOD])); 119 } 120 121 spin_unlock_irqrestore(&dev->event_lock, flags); 122 } 123 124 static void input_start_autorepeat(struct input_dev *dev, int code) 125 { 126 if (test_bit(EV_REP, dev->evbit) && 127 dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] && 128 dev->timer.data) { 129 dev->repeat_key = code; 130 mod_timer(&dev->timer, 131 jiffies + msecs_to_jiffies(dev->rep[REP_DELAY])); 132 } 133 } 134 135 #define INPUT_IGNORE_EVENT 0 136 #define INPUT_PASS_TO_HANDLERS 1 137 #define INPUT_PASS_TO_DEVICE 2 138 #define INPUT_PASS_TO_ALL (INPUT_PASS_TO_HANDLERS | INPUT_PASS_TO_DEVICE) 139 140 static void input_handle_event(struct input_dev *dev, 141 unsigned int type, unsigned int code, int value) 142 { 143 int disposition = INPUT_IGNORE_EVENT; 144 145 switch (type) { 146 147 case EV_SYN: 148 switch (code) { 149 case SYN_CONFIG: 150 disposition = INPUT_PASS_TO_ALL; 151 break; 152 153 case SYN_REPORT: 154 if (!dev->sync) { 155 dev->sync = 1; 156 disposition = INPUT_PASS_TO_HANDLERS; 157 } 158 break; 159 } 160 break; 161 162 case EV_KEY: 163 if (is_event_supported(code, dev->keybit, KEY_MAX) && 164 !!test_bit(code, dev->key) != value) { 165 166 if (value != 2) { 167 __change_bit(code, dev->key); 168 if (value) 169 input_start_autorepeat(dev, code); 170 } 171 172 disposition = INPUT_PASS_TO_HANDLERS; 173 } 174 break; 175 176 case EV_SW: 177 if (is_event_supported(code, dev->swbit, SW_MAX) && 178 !!test_bit(code, dev->sw) != value) { 179 180 __change_bit(code, dev->sw); 181 disposition = INPUT_PASS_TO_HANDLERS; 182 } 183 break; 184 185 case EV_ABS: 186 if (is_event_supported(code, dev->absbit, ABS_MAX)) { 187 188 value = input_defuzz_abs_event(value, 189 dev->abs[code], dev->absfuzz[code]); 190 191 if (dev->abs[code] != value) { 192 dev->abs[code] = value; 193 disposition = INPUT_PASS_TO_HANDLERS; 194 } 195 } 196 break; 197 198 case EV_REL: 199 if (is_event_supported(code, dev->relbit, REL_MAX) && value) 200 disposition = INPUT_PASS_TO_HANDLERS; 201 202 break; 203 204 case EV_MSC: 205 if (is_event_supported(code, dev->mscbit, MSC_MAX)) 206 disposition = INPUT_PASS_TO_ALL; 207 208 break; 209 210 case EV_LED: 211 if (is_event_supported(code, dev->ledbit, LED_MAX) && 212 !!test_bit(code, dev->led) != value) { 213 214 __change_bit(code, dev->led); 215 disposition = INPUT_PASS_TO_ALL; 216 } 217 break; 218 219 case EV_SND: 220 if (is_event_supported(code, dev->sndbit, SND_MAX)) { 221 222 if (!!test_bit(code, dev->snd) != !!value) 223 __change_bit(code, dev->snd); 224 disposition = INPUT_PASS_TO_ALL; 225 } 226 break; 227 228 case EV_REP: 229 if (code <= REP_MAX && value >= 0 && dev->rep[code] != value) { 230 dev->rep[code] = value; 231 disposition = INPUT_PASS_TO_ALL; 232 } 233 break; 234 235 case EV_FF: 236 if (value >= 0) 237 disposition = INPUT_PASS_TO_ALL; 238 break; 239 240 case EV_PWR: 241 disposition = INPUT_PASS_TO_ALL; 242 break; 243 } 244 245 if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN) 246 dev->sync = 0; 247 248 if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event) 249 dev->event(dev, type, code, value); 250 251 if (disposition & INPUT_PASS_TO_HANDLERS) 252 input_pass_event(dev, type, code, value); 253 } 254 255 /** 256 * input_event() - report new input event 257 * @dev: device that generated the event 258 * @type: type of the event 259 * @code: event code 260 * @value: value of the event 261 * 262 * This function should be used by drivers implementing various input 263 * devices. See also input_inject_event(). 264 */ 265 266 void input_event(struct input_dev *dev, 267 unsigned int type, unsigned int code, int value) 268 { 269 unsigned long flags; 270 271 if (is_event_supported(type, dev->evbit, EV_MAX)) { 272 273 spin_lock_irqsave(&dev->event_lock, flags); 274 add_input_randomness(type, code, value); 275 input_handle_event(dev, type, code, value); 276 spin_unlock_irqrestore(&dev->event_lock, flags); 277 } 278 } 279 EXPORT_SYMBOL(input_event); 280 281 /** 282 * input_inject_event() - send input event from input handler 283 * @handle: input handle to send event through 284 * @type: type of the event 285 * @code: event code 286 * @value: value of the event 287 * 288 * Similar to input_event() but will ignore event if device is 289 * "grabbed" and handle injecting event is not the one that owns 290 * the device. 291 */ 292 void input_inject_event(struct input_handle *handle, 293 unsigned int type, unsigned int code, int value) 294 { 295 struct input_dev *dev = handle->dev; 296 struct input_handle *grab; 297 unsigned long flags; 298 299 if (is_event_supported(type, dev->evbit, EV_MAX)) { 300 spin_lock_irqsave(&dev->event_lock, flags); 301 302 rcu_read_lock(); 303 grab = rcu_dereference(dev->grab); 304 if (!grab || grab == handle) 305 input_handle_event(dev, type, code, value); 306 rcu_read_unlock(); 307 308 spin_unlock_irqrestore(&dev->event_lock, flags); 309 } 310 } 311 EXPORT_SYMBOL(input_inject_event); 312 313 /** 314 * input_grab_device - grabs device for exclusive use 315 * @handle: input handle that wants to own the device 316 * 317 * When a device is grabbed by an input handle all events generated by 318 * the device are delivered only to this handle. Also events injected 319 * by other input handles are ignored while device is grabbed. 320 */ 321 int input_grab_device(struct input_handle *handle) 322 { 323 struct input_dev *dev = handle->dev; 324 int retval; 325 326 retval = mutex_lock_interruptible(&dev->mutex); 327 if (retval) 328 return retval; 329 330 if (dev->grab) { 331 retval = -EBUSY; 332 goto out; 333 } 334 335 rcu_assign_pointer(dev->grab, handle); 336 synchronize_rcu(); 337 338 out: 339 mutex_unlock(&dev->mutex); 340 return retval; 341 } 342 EXPORT_SYMBOL(input_grab_device); 343 344 static void __input_release_device(struct input_handle *handle) 345 { 346 struct input_dev *dev = handle->dev; 347 348 if (dev->grab == handle) { 349 rcu_assign_pointer(dev->grab, NULL); 350 /* Make sure input_pass_event() notices that grab is gone */ 351 synchronize_rcu(); 352 353 list_for_each_entry(handle, &dev->h_list, d_node) 354 if (handle->open && handle->handler->start) 355 handle->handler->start(handle); 356 } 357 } 358 359 /** 360 * input_release_device - release previously grabbed device 361 * @handle: input handle that owns the device 362 * 363 * Releases previously grabbed device so that other input handles can 364 * start receiving input events. Upon release all handlers attached 365 * to the device have their start() method called so they have a change 366 * to synchronize device state with the rest of the system. 367 */ 368 void input_release_device(struct input_handle *handle) 369 { 370 struct input_dev *dev = handle->dev; 371 372 mutex_lock(&dev->mutex); 373 __input_release_device(handle); 374 mutex_unlock(&dev->mutex); 375 } 376 EXPORT_SYMBOL(input_release_device); 377 378 /** 379 * input_open_device - open input device 380 * @handle: handle through which device is being accessed 381 * 382 * This function should be called by input handlers when they 383 * want to start receive events from given input device. 384 */ 385 int input_open_device(struct input_handle *handle) 386 { 387 struct input_dev *dev = handle->dev; 388 int retval; 389 390 retval = mutex_lock_interruptible(&dev->mutex); 391 if (retval) 392 return retval; 393 394 if (dev->going_away) { 395 retval = -ENODEV; 396 goto out; 397 } 398 399 handle->open++; 400 401 if (!dev->users++ && dev->open) 402 retval = dev->open(dev); 403 404 if (retval) { 405 dev->users--; 406 if (!--handle->open) { 407 /* 408 * Make sure we are not delivering any more events 409 * through this handle 410 */ 411 synchronize_rcu(); 412 } 413 } 414 415 out: 416 mutex_unlock(&dev->mutex); 417 return retval; 418 } 419 EXPORT_SYMBOL(input_open_device); 420 421 int input_flush_device(struct input_handle *handle, struct file *file) 422 { 423 struct input_dev *dev = handle->dev; 424 int retval; 425 426 retval = mutex_lock_interruptible(&dev->mutex); 427 if (retval) 428 return retval; 429 430 if (dev->flush) 431 retval = dev->flush(dev, file); 432 433 mutex_unlock(&dev->mutex); 434 return retval; 435 } 436 EXPORT_SYMBOL(input_flush_device); 437 438 /** 439 * input_close_device - close input device 440 * @handle: handle through which device is being accessed 441 * 442 * This function should be called by input handlers when they 443 * want to stop receive events from given input device. 444 */ 445 void input_close_device(struct input_handle *handle) 446 { 447 struct input_dev *dev = handle->dev; 448 449 mutex_lock(&dev->mutex); 450 451 __input_release_device(handle); 452 453 if (!--dev->users && dev->close) 454 dev->close(dev); 455 456 if (!--handle->open) { 457 /* 458 * synchronize_rcu() makes sure that input_pass_event() 459 * completed and that no more input events are delivered 460 * through this handle 461 */ 462 synchronize_rcu(); 463 } 464 465 mutex_unlock(&dev->mutex); 466 } 467 EXPORT_SYMBOL(input_close_device); 468 469 /* 470 * Prepare device for unregistering 471 */ 472 static void input_disconnect_device(struct input_dev *dev) 473 { 474 struct input_handle *handle; 475 int code; 476 477 /* 478 * Mark device as going away. Note that we take dev->mutex here 479 * not to protect access to dev->going_away but rather to ensure 480 * that there are no threads in the middle of input_open_device() 481 */ 482 mutex_lock(&dev->mutex); 483 dev->going_away = 1; 484 mutex_unlock(&dev->mutex); 485 486 spin_lock_irq(&dev->event_lock); 487 488 /* 489 * Simulate keyup events for all pressed keys so that handlers 490 * are not left with "stuck" keys. The driver may continue 491 * generate events even after we done here but they will not 492 * reach any handlers. 493 */ 494 if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) { 495 for (code = 0; code <= KEY_MAX; code++) { 496 if (is_event_supported(code, dev->keybit, KEY_MAX) && 497 __test_and_clear_bit(code, dev->key)) { 498 input_pass_event(dev, EV_KEY, code, 0); 499 } 500 } 501 input_pass_event(dev, EV_SYN, SYN_REPORT, 1); 502 } 503 504 list_for_each_entry(handle, &dev->h_list, d_node) 505 handle->open = 0; 506 507 spin_unlock_irq(&dev->event_lock); 508 } 509 510 static int input_fetch_keycode(struct input_dev *dev, int scancode) 511 { 512 switch (dev->keycodesize) { 513 case 1: 514 return ((u8 *)dev->keycode)[scancode]; 515 516 case 2: 517 return ((u16 *)dev->keycode)[scancode]; 518 519 default: 520 return ((u32 *)dev->keycode)[scancode]; 521 } 522 } 523 524 static int input_default_getkeycode(struct input_dev *dev, 525 int scancode, int *keycode) 526 { 527 if (!dev->keycodesize) 528 return -EINVAL; 529 530 if (scancode >= dev->keycodemax) 531 return -EINVAL; 532 533 *keycode = input_fetch_keycode(dev, scancode); 534 535 return 0; 536 } 537 538 static int input_default_setkeycode(struct input_dev *dev, 539 int scancode, int keycode) 540 { 541 int old_keycode; 542 int i; 543 544 if (scancode >= dev->keycodemax) 545 return -EINVAL; 546 547 if (!dev->keycodesize) 548 return -EINVAL; 549 550 if (dev->keycodesize < sizeof(keycode) && (keycode >> (dev->keycodesize * 8))) 551 return -EINVAL; 552 553 switch (dev->keycodesize) { 554 case 1: { 555 u8 *k = (u8 *)dev->keycode; 556 old_keycode = k[scancode]; 557 k[scancode] = keycode; 558 break; 559 } 560 case 2: { 561 u16 *k = (u16 *)dev->keycode; 562 old_keycode = k[scancode]; 563 k[scancode] = keycode; 564 break; 565 } 566 default: { 567 u32 *k = (u32 *)dev->keycode; 568 old_keycode = k[scancode]; 569 k[scancode] = keycode; 570 break; 571 } 572 } 573 574 clear_bit(old_keycode, dev->keybit); 575 set_bit(keycode, dev->keybit); 576 577 for (i = 0; i < dev->keycodemax; i++) { 578 if (input_fetch_keycode(dev, i) == old_keycode) { 579 set_bit(old_keycode, dev->keybit); 580 break; /* Setting the bit twice is useless, so break */ 581 } 582 } 583 584 return 0; 585 } 586 587 /** 588 * input_get_keycode - retrieve keycode currently mapped to a given scancode 589 * @dev: input device which keymap is being queried 590 * @scancode: scancode (or its equivalent for device in question) for which 591 * keycode is needed 592 * @keycode: result 593 * 594 * This function should be called by anyone interested in retrieving current 595 * keymap. Presently keyboard and evdev handlers use it. 596 */ 597 int input_get_keycode(struct input_dev *dev, int scancode, int *keycode) 598 { 599 if (scancode < 0) 600 return -EINVAL; 601 602 return dev->getkeycode(dev, scancode, keycode); 603 } 604 EXPORT_SYMBOL(input_get_keycode); 605 606 /** 607 * input_get_keycode - assign new keycode to a given scancode 608 * @dev: input device which keymap is being updated 609 * @scancode: scancode (or its equivalent for device in question) 610 * @keycode: new keycode to be assigned to the scancode 611 * 612 * This function should be called by anyone needing to update current 613 * keymap. Presently keyboard and evdev handlers use it. 614 */ 615 int input_set_keycode(struct input_dev *dev, int scancode, int keycode) 616 { 617 unsigned long flags; 618 int old_keycode; 619 int retval; 620 621 if (scancode < 0) 622 return -EINVAL; 623 624 if (keycode < 0 || keycode > KEY_MAX) 625 return -EINVAL; 626 627 spin_lock_irqsave(&dev->event_lock, flags); 628 629 retval = dev->getkeycode(dev, scancode, &old_keycode); 630 if (retval) 631 goto out; 632 633 retval = dev->setkeycode(dev, scancode, keycode); 634 if (retval) 635 goto out; 636 637 /* 638 * Simulate keyup event if keycode is not present 639 * in the keymap anymore 640 */ 641 if (test_bit(EV_KEY, dev->evbit) && 642 !is_event_supported(old_keycode, dev->keybit, KEY_MAX) && 643 __test_and_clear_bit(old_keycode, dev->key)) { 644 645 input_pass_event(dev, EV_KEY, old_keycode, 0); 646 if (dev->sync) 647 input_pass_event(dev, EV_SYN, SYN_REPORT, 1); 648 } 649 650 out: 651 spin_unlock_irqrestore(&dev->event_lock, flags); 652 653 return retval; 654 } 655 EXPORT_SYMBOL(input_set_keycode); 656 657 #define MATCH_BIT(bit, max) \ 658 for (i = 0; i < BITS_TO_LONGS(max); i++) \ 659 if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \ 660 break; \ 661 if (i != BITS_TO_LONGS(max)) \ 662 continue; 663 664 static const struct input_device_id *input_match_device(const struct input_device_id *id, 665 struct input_dev *dev) 666 { 667 int i; 668 669 for (; id->flags || id->driver_info; id++) { 670 671 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS) 672 if (id->bustype != dev->id.bustype) 673 continue; 674 675 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR) 676 if (id->vendor != dev->id.vendor) 677 continue; 678 679 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT) 680 if (id->product != dev->id.product) 681 continue; 682 683 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION) 684 if (id->version != dev->id.version) 685 continue; 686 687 MATCH_BIT(evbit, EV_MAX); 688 MATCH_BIT(keybit, KEY_MAX); 689 MATCH_BIT(relbit, REL_MAX); 690 MATCH_BIT(absbit, ABS_MAX); 691 MATCH_BIT(mscbit, MSC_MAX); 692 MATCH_BIT(ledbit, LED_MAX); 693 MATCH_BIT(sndbit, SND_MAX); 694 MATCH_BIT(ffbit, FF_MAX); 695 MATCH_BIT(swbit, SW_MAX); 696 697 return id; 698 } 699 700 return NULL; 701 } 702 703 static int input_attach_handler(struct input_dev *dev, struct input_handler *handler) 704 { 705 const struct input_device_id *id; 706 int error; 707 708 if (handler->blacklist && input_match_device(handler->blacklist, dev)) 709 return -ENODEV; 710 711 id = input_match_device(handler->id_table, dev); 712 if (!id) 713 return -ENODEV; 714 715 error = handler->connect(handler, dev, id); 716 if (error && error != -ENODEV) 717 printk(KERN_ERR 718 "input: failed to attach handler %s to device %s, " 719 "error: %d\n", 720 handler->name, kobject_name(&dev->dev.kobj), error); 721 722 return error; 723 } 724 725 726 #ifdef CONFIG_PROC_FS 727 728 static struct proc_dir_entry *proc_bus_input_dir; 729 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait); 730 static int input_devices_state; 731 732 static inline void input_wakeup_procfs_readers(void) 733 { 734 input_devices_state++; 735 wake_up(&input_devices_poll_wait); 736 } 737 738 static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait) 739 { 740 int state = input_devices_state; 741 742 poll_wait(file, &input_devices_poll_wait, wait); 743 if (state != input_devices_state) 744 return POLLIN | POLLRDNORM; 745 746 return 0; 747 } 748 749 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos) 750 { 751 if (mutex_lock_interruptible(&input_mutex)) 752 return NULL; 753 754 return seq_list_start(&input_dev_list, *pos); 755 } 756 757 static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos) 758 { 759 return seq_list_next(v, &input_dev_list, pos); 760 } 761 762 static void input_devices_seq_stop(struct seq_file *seq, void *v) 763 { 764 mutex_unlock(&input_mutex); 765 } 766 767 static void input_seq_print_bitmap(struct seq_file *seq, const char *name, 768 unsigned long *bitmap, int max) 769 { 770 int i; 771 772 for (i = BITS_TO_LONGS(max) - 1; i > 0; i--) 773 if (bitmap[i]) 774 break; 775 776 seq_printf(seq, "B: %s=", name); 777 for (; i >= 0; i--) 778 seq_printf(seq, "%lx%s", bitmap[i], i > 0 ? " " : ""); 779 seq_putc(seq, '\n'); 780 } 781 782 static int input_devices_seq_show(struct seq_file *seq, void *v) 783 { 784 struct input_dev *dev = container_of(v, struct input_dev, node); 785 const char *path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL); 786 struct input_handle *handle; 787 788 seq_printf(seq, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n", 789 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version); 790 791 seq_printf(seq, "N: Name=\"%s\"\n", dev->name ? dev->name : ""); 792 seq_printf(seq, "P: Phys=%s\n", dev->phys ? dev->phys : ""); 793 seq_printf(seq, "S: Sysfs=%s\n", path ? path : ""); 794 seq_printf(seq, "U: Uniq=%s\n", dev->uniq ? dev->uniq : ""); 795 seq_printf(seq, "H: Handlers="); 796 797 list_for_each_entry(handle, &dev->h_list, d_node) 798 seq_printf(seq, "%s ", handle->name); 799 seq_putc(seq, '\n'); 800 801 input_seq_print_bitmap(seq, "EV", dev->evbit, EV_MAX); 802 if (test_bit(EV_KEY, dev->evbit)) 803 input_seq_print_bitmap(seq, "KEY", dev->keybit, KEY_MAX); 804 if (test_bit(EV_REL, dev->evbit)) 805 input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX); 806 if (test_bit(EV_ABS, dev->evbit)) 807 input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX); 808 if (test_bit(EV_MSC, dev->evbit)) 809 input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX); 810 if (test_bit(EV_LED, dev->evbit)) 811 input_seq_print_bitmap(seq, "LED", dev->ledbit, LED_MAX); 812 if (test_bit(EV_SND, dev->evbit)) 813 input_seq_print_bitmap(seq, "SND", dev->sndbit, SND_MAX); 814 if (test_bit(EV_FF, dev->evbit)) 815 input_seq_print_bitmap(seq, "FF", dev->ffbit, FF_MAX); 816 if (test_bit(EV_SW, dev->evbit)) 817 input_seq_print_bitmap(seq, "SW", dev->swbit, SW_MAX); 818 819 seq_putc(seq, '\n'); 820 821 kfree(path); 822 return 0; 823 } 824 825 static const struct seq_operations input_devices_seq_ops = { 826 .start = input_devices_seq_start, 827 .next = input_devices_seq_next, 828 .stop = input_devices_seq_stop, 829 .show = input_devices_seq_show, 830 }; 831 832 static int input_proc_devices_open(struct inode *inode, struct file *file) 833 { 834 return seq_open(file, &input_devices_seq_ops); 835 } 836 837 static const struct file_operations input_devices_fileops = { 838 .owner = THIS_MODULE, 839 .open = input_proc_devices_open, 840 .poll = input_proc_devices_poll, 841 .read = seq_read, 842 .llseek = seq_lseek, 843 .release = seq_release, 844 }; 845 846 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos) 847 { 848 if (mutex_lock_interruptible(&input_mutex)) 849 return NULL; 850 851 seq->private = (void *)(unsigned long)*pos; 852 return seq_list_start(&input_handler_list, *pos); 853 } 854 855 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos) 856 { 857 seq->private = (void *)(unsigned long)(*pos + 1); 858 return seq_list_next(v, &input_handler_list, pos); 859 } 860 861 static void input_handlers_seq_stop(struct seq_file *seq, void *v) 862 { 863 mutex_unlock(&input_mutex); 864 } 865 866 static int input_handlers_seq_show(struct seq_file *seq, void *v) 867 { 868 struct input_handler *handler = container_of(v, struct input_handler, node); 869 870 seq_printf(seq, "N: Number=%ld Name=%s", 871 (unsigned long)seq->private, handler->name); 872 if (handler->fops) 873 seq_printf(seq, " Minor=%d", handler->minor); 874 seq_putc(seq, '\n'); 875 876 return 0; 877 } 878 static const struct seq_operations input_handlers_seq_ops = { 879 .start = input_handlers_seq_start, 880 .next = input_handlers_seq_next, 881 .stop = input_handlers_seq_stop, 882 .show = input_handlers_seq_show, 883 }; 884 885 static int input_proc_handlers_open(struct inode *inode, struct file *file) 886 { 887 return seq_open(file, &input_handlers_seq_ops); 888 } 889 890 static const struct file_operations input_handlers_fileops = { 891 .owner = THIS_MODULE, 892 .open = input_proc_handlers_open, 893 .read = seq_read, 894 .llseek = seq_lseek, 895 .release = seq_release, 896 }; 897 898 static int __init input_proc_init(void) 899 { 900 struct proc_dir_entry *entry; 901 902 proc_bus_input_dir = proc_mkdir("bus/input", NULL); 903 if (!proc_bus_input_dir) 904 return -ENOMEM; 905 906 entry = proc_create("devices", 0, proc_bus_input_dir, 907 &input_devices_fileops); 908 if (!entry) 909 goto fail1; 910 911 entry = proc_create("handlers", 0, proc_bus_input_dir, 912 &input_handlers_fileops); 913 if (!entry) 914 goto fail2; 915 916 return 0; 917 918 fail2: remove_proc_entry("devices", proc_bus_input_dir); 919 fail1: remove_proc_entry("bus/input", NULL); 920 return -ENOMEM; 921 } 922 923 static void input_proc_exit(void) 924 { 925 remove_proc_entry("devices", proc_bus_input_dir); 926 remove_proc_entry("handlers", proc_bus_input_dir); 927 remove_proc_entry("bus/input", NULL); 928 } 929 930 #else /* !CONFIG_PROC_FS */ 931 static inline void input_wakeup_procfs_readers(void) { } 932 static inline int input_proc_init(void) { return 0; } 933 static inline void input_proc_exit(void) { } 934 #endif 935 936 #define INPUT_DEV_STRING_ATTR_SHOW(name) \ 937 static ssize_t input_dev_show_##name(struct device *dev, \ 938 struct device_attribute *attr, \ 939 char *buf) \ 940 { \ 941 struct input_dev *input_dev = to_input_dev(dev); \ 942 \ 943 return scnprintf(buf, PAGE_SIZE, "%s\n", \ 944 input_dev->name ? input_dev->name : ""); \ 945 } \ 946 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_##name, NULL) 947 948 INPUT_DEV_STRING_ATTR_SHOW(name); 949 INPUT_DEV_STRING_ATTR_SHOW(phys); 950 INPUT_DEV_STRING_ATTR_SHOW(uniq); 951 952 static int input_print_modalias_bits(char *buf, int size, 953 char name, unsigned long *bm, 954 unsigned int min_bit, unsigned int max_bit) 955 { 956 int len = 0, i; 957 958 len += snprintf(buf, max(size, 0), "%c", name); 959 for (i = min_bit; i < max_bit; i++) 960 if (bm[BIT_WORD(i)] & BIT_MASK(i)) 961 len += snprintf(buf + len, max(size - len, 0), "%X,", i); 962 return len; 963 } 964 965 static int input_print_modalias(char *buf, int size, struct input_dev *id, 966 int add_cr) 967 { 968 int len; 969 970 len = snprintf(buf, max(size, 0), 971 "input:b%04Xv%04Xp%04Xe%04X-", 972 id->id.bustype, id->id.vendor, 973 id->id.product, id->id.version); 974 975 len += input_print_modalias_bits(buf + len, size - len, 976 'e', id->evbit, 0, EV_MAX); 977 len += input_print_modalias_bits(buf + len, size - len, 978 'k', id->keybit, KEY_MIN_INTERESTING, KEY_MAX); 979 len += input_print_modalias_bits(buf + len, size - len, 980 'r', id->relbit, 0, REL_MAX); 981 len += input_print_modalias_bits(buf + len, size - len, 982 'a', id->absbit, 0, ABS_MAX); 983 len += input_print_modalias_bits(buf + len, size - len, 984 'm', id->mscbit, 0, MSC_MAX); 985 len += input_print_modalias_bits(buf + len, size - len, 986 'l', id->ledbit, 0, LED_MAX); 987 len += input_print_modalias_bits(buf + len, size - len, 988 's', id->sndbit, 0, SND_MAX); 989 len += input_print_modalias_bits(buf + len, size - len, 990 'f', id->ffbit, 0, FF_MAX); 991 len += input_print_modalias_bits(buf + len, size - len, 992 'w', id->swbit, 0, SW_MAX); 993 994 if (add_cr) 995 len += snprintf(buf + len, max(size - len, 0), "\n"); 996 997 return len; 998 } 999 1000 static ssize_t input_dev_show_modalias(struct device *dev, 1001 struct device_attribute *attr, 1002 char *buf) 1003 { 1004 struct input_dev *id = to_input_dev(dev); 1005 ssize_t len; 1006 1007 len = input_print_modalias(buf, PAGE_SIZE, id, 1); 1008 1009 return min_t(int, len, PAGE_SIZE); 1010 } 1011 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL); 1012 1013 static struct attribute *input_dev_attrs[] = { 1014 &dev_attr_name.attr, 1015 &dev_attr_phys.attr, 1016 &dev_attr_uniq.attr, 1017 &dev_attr_modalias.attr, 1018 NULL 1019 }; 1020 1021 static struct attribute_group input_dev_attr_group = { 1022 .attrs = input_dev_attrs, 1023 }; 1024 1025 #define INPUT_DEV_ID_ATTR(name) \ 1026 static ssize_t input_dev_show_id_##name(struct device *dev, \ 1027 struct device_attribute *attr, \ 1028 char *buf) \ 1029 { \ 1030 struct input_dev *input_dev = to_input_dev(dev); \ 1031 return scnprintf(buf, PAGE_SIZE, "%04x\n", input_dev->id.name); \ 1032 } \ 1033 static DEVICE_ATTR(name, S_IRUGO, input_dev_show_id_##name, NULL) 1034 1035 INPUT_DEV_ID_ATTR(bustype); 1036 INPUT_DEV_ID_ATTR(vendor); 1037 INPUT_DEV_ID_ATTR(product); 1038 INPUT_DEV_ID_ATTR(version); 1039 1040 static struct attribute *input_dev_id_attrs[] = { 1041 &dev_attr_bustype.attr, 1042 &dev_attr_vendor.attr, 1043 &dev_attr_product.attr, 1044 &dev_attr_version.attr, 1045 NULL 1046 }; 1047 1048 static struct attribute_group input_dev_id_attr_group = { 1049 .name = "id", 1050 .attrs = input_dev_id_attrs, 1051 }; 1052 1053 static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap, 1054 int max, int add_cr) 1055 { 1056 int i; 1057 int len = 0; 1058 1059 for (i = BITS_TO_LONGS(max) - 1; i > 0; i--) 1060 if (bitmap[i]) 1061 break; 1062 1063 for (; i >= 0; i--) 1064 len += snprintf(buf + len, max(buf_size - len, 0), 1065 "%lx%s", bitmap[i], i > 0 ? " " : ""); 1066 1067 if (add_cr) 1068 len += snprintf(buf + len, max(buf_size - len, 0), "\n"); 1069 1070 return len; 1071 } 1072 1073 #define INPUT_DEV_CAP_ATTR(ev, bm) \ 1074 static ssize_t input_dev_show_cap_##bm(struct device *dev, \ 1075 struct device_attribute *attr, \ 1076 char *buf) \ 1077 { \ 1078 struct input_dev *input_dev = to_input_dev(dev); \ 1079 int len = input_print_bitmap(buf, PAGE_SIZE, \ 1080 input_dev->bm##bit, ev##_MAX, 1); \ 1081 return min_t(int, len, PAGE_SIZE); \ 1082 } \ 1083 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL) 1084 1085 INPUT_DEV_CAP_ATTR(EV, ev); 1086 INPUT_DEV_CAP_ATTR(KEY, key); 1087 INPUT_DEV_CAP_ATTR(REL, rel); 1088 INPUT_DEV_CAP_ATTR(ABS, abs); 1089 INPUT_DEV_CAP_ATTR(MSC, msc); 1090 INPUT_DEV_CAP_ATTR(LED, led); 1091 INPUT_DEV_CAP_ATTR(SND, snd); 1092 INPUT_DEV_CAP_ATTR(FF, ff); 1093 INPUT_DEV_CAP_ATTR(SW, sw); 1094 1095 static struct attribute *input_dev_caps_attrs[] = { 1096 &dev_attr_ev.attr, 1097 &dev_attr_key.attr, 1098 &dev_attr_rel.attr, 1099 &dev_attr_abs.attr, 1100 &dev_attr_msc.attr, 1101 &dev_attr_led.attr, 1102 &dev_attr_snd.attr, 1103 &dev_attr_ff.attr, 1104 &dev_attr_sw.attr, 1105 NULL 1106 }; 1107 1108 static struct attribute_group input_dev_caps_attr_group = { 1109 .name = "capabilities", 1110 .attrs = input_dev_caps_attrs, 1111 }; 1112 1113 static struct attribute_group *input_dev_attr_groups[] = { 1114 &input_dev_attr_group, 1115 &input_dev_id_attr_group, 1116 &input_dev_caps_attr_group, 1117 NULL 1118 }; 1119 1120 static void input_dev_release(struct device *device) 1121 { 1122 struct input_dev *dev = to_input_dev(device); 1123 1124 input_ff_destroy(dev); 1125 kfree(dev); 1126 1127 module_put(THIS_MODULE); 1128 } 1129 1130 /* 1131 * Input uevent interface - loading event handlers based on 1132 * device bitfields. 1133 */ 1134 static int input_add_uevent_bm_var(struct kobj_uevent_env *env, 1135 const char *name, unsigned long *bitmap, int max) 1136 { 1137 int len; 1138 1139 if (add_uevent_var(env, "%s=", name)) 1140 return -ENOMEM; 1141 1142 len = input_print_bitmap(&env->buf[env->buflen - 1], 1143 sizeof(env->buf) - env->buflen, 1144 bitmap, max, 0); 1145 if (len >= (sizeof(env->buf) - env->buflen)) 1146 return -ENOMEM; 1147 1148 env->buflen += len; 1149 return 0; 1150 } 1151 1152 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env, 1153 struct input_dev *dev) 1154 { 1155 int len; 1156 1157 if (add_uevent_var(env, "MODALIAS=")) 1158 return -ENOMEM; 1159 1160 len = input_print_modalias(&env->buf[env->buflen - 1], 1161 sizeof(env->buf) - env->buflen, 1162 dev, 0); 1163 if (len >= (sizeof(env->buf) - env->buflen)) 1164 return -ENOMEM; 1165 1166 env->buflen += len; 1167 return 0; 1168 } 1169 1170 #define INPUT_ADD_HOTPLUG_VAR(fmt, val...) \ 1171 do { \ 1172 int err = add_uevent_var(env, fmt, val); \ 1173 if (err) \ 1174 return err; \ 1175 } while (0) 1176 1177 #define INPUT_ADD_HOTPLUG_BM_VAR(name, bm, max) \ 1178 do { \ 1179 int err = input_add_uevent_bm_var(env, name, bm, max); \ 1180 if (err) \ 1181 return err; \ 1182 } while (0) 1183 1184 #define INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev) \ 1185 do { \ 1186 int err = input_add_uevent_modalias_var(env, dev); \ 1187 if (err) \ 1188 return err; \ 1189 } while (0) 1190 1191 static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env) 1192 { 1193 struct input_dev *dev = to_input_dev(device); 1194 1195 INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x", 1196 dev->id.bustype, dev->id.vendor, 1197 dev->id.product, dev->id.version); 1198 if (dev->name) 1199 INPUT_ADD_HOTPLUG_VAR("NAME=\"%s\"", dev->name); 1200 if (dev->phys) 1201 INPUT_ADD_HOTPLUG_VAR("PHYS=\"%s\"", dev->phys); 1202 if (dev->uniq) 1203 INPUT_ADD_HOTPLUG_VAR("UNIQ=\"%s\"", dev->uniq); 1204 1205 INPUT_ADD_HOTPLUG_BM_VAR("EV=", dev->evbit, EV_MAX); 1206 if (test_bit(EV_KEY, dev->evbit)) 1207 INPUT_ADD_HOTPLUG_BM_VAR("KEY=", dev->keybit, KEY_MAX); 1208 if (test_bit(EV_REL, dev->evbit)) 1209 INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX); 1210 if (test_bit(EV_ABS, dev->evbit)) 1211 INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX); 1212 if (test_bit(EV_MSC, dev->evbit)) 1213 INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX); 1214 if (test_bit(EV_LED, dev->evbit)) 1215 INPUT_ADD_HOTPLUG_BM_VAR("LED=", dev->ledbit, LED_MAX); 1216 if (test_bit(EV_SND, dev->evbit)) 1217 INPUT_ADD_HOTPLUG_BM_VAR("SND=", dev->sndbit, SND_MAX); 1218 if (test_bit(EV_FF, dev->evbit)) 1219 INPUT_ADD_HOTPLUG_BM_VAR("FF=", dev->ffbit, FF_MAX); 1220 if (test_bit(EV_SW, dev->evbit)) 1221 INPUT_ADD_HOTPLUG_BM_VAR("SW=", dev->swbit, SW_MAX); 1222 1223 INPUT_ADD_HOTPLUG_MODALIAS_VAR(dev); 1224 1225 return 0; 1226 } 1227 1228 static struct device_type input_dev_type = { 1229 .groups = input_dev_attr_groups, 1230 .release = input_dev_release, 1231 .uevent = input_dev_uevent, 1232 }; 1233 1234 struct class input_class = { 1235 .name = "input", 1236 }; 1237 EXPORT_SYMBOL_GPL(input_class); 1238 1239 /** 1240 * input_allocate_device - allocate memory for new input device 1241 * 1242 * Returns prepared struct input_dev or NULL. 1243 * 1244 * NOTE: Use input_free_device() to free devices that have not been 1245 * registered; input_unregister_device() should be used for already 1246 * registered devices. 1247 */ 1248 struct input_dev *input_allocate_device(void) 1249 { 1250 struct input_dev *dev; 1251 1252 dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL); 1253 if (dev) { 1254 dev->dev.type = &input_dev_type; 1255 dev->dev.class = &input_class; 1256 device_initialize(&dev->dev); 1257 mutex_init(&dev->mutex); 1258 spin_lock_init(&dev->event_lock); 1259 INIT_LIST_HEAD(&dev->h_list); 1260 INIT_LIST_HEAD(&dev->node); 1261 1262 __module_get(THIS_MODULE); 1263 } 1264 1265 return dev; 1266 } 1267 EXPORT_SYMBOL(input_allocate_device); 1268 1269 /** 1270 * input_free_device - free memory occupied by input_dev structure 1271 * @dev: input device to free 1272 * 1273 * This function should only be used if input_register_device() 1274 * was not called yet or if it failed. Once device was registered 1275 * use input_unregister_device() and memory will be freed once last 1276 * reference to the device is dropped. 1277 * 1278 * Device should be allocated by input_allocate_device(). 1279 * 1280 * NOTE: If there are references to the input device then memory 1281 * will not be freed until last reference is dropped. 1282 */ 1283 void input_free_device(struct input_dev *dev) 1284 { 1285 if (dev) 1286 input_put_device(dev); 1287 } 1288 EXPORT_SYMBOL(input_free_device); 1289 1290 /** 1291 * input_set_capability - mark device as capable of a certain event 1292 * @dev: device that is capable of emitting or accepting event 1293 * @type: type of the event (EV_KEY, EV_REL, etc...) 1294 * @code: event code 1295 * 1296 * In addition to setting up corresponding bit in appropriate capability 1297 * bitmap the function also adjusts dev->evbit. 1298 */ 1299 void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code) 1300 { 1301 switch (type) { 1302 case EV_KEY: 1303 __set_bit(code, dev->keybit); 1304 break; 1305 1306 case EV_REL: 1307 __set_bit(code, dev->relbit); 1308 break; 1309 1310 case EV_ABS: 1311 __set_bit(code, dev->absbit); 1312 break; 1313 1314 case EV_MSC: 1315 __set_bit(code, dev->mscbit); 1316 break; 1317 1318 case EV_SW: 1319 __set_bit(code, dev->swbit); 1320 break; 1321 1322 case EV_LED: 1323 __set_bit(code, dev->ledbit); 1324 break; 1325 1326 case EV_SND: 1327 __set_bit(code, dev->sndbit); 1328 break; 1329 1330 case EV_FF: 1331 __set_bit(code, dev->ffbit); 1332 break; 1333 1334 case EV_PWR: 1335 /* do nothing */ 1336 break; 1337 1338 default: 1339 printk(KERN_ERR 1340 "input_set_capability: unknown type %u (code %u)\n", 1341 type, code); 1342 dump_stack(); 1343 return; 1344 } 1345 1346 __set_bit(type, dev->evbit); 1347 } 1348 EXPORT_SYMBOL(input_set_capability); 1349 1350 /** 1351 * input_register_device - register device with input core 1352 * @dev: device to be registered 1353 * 1354 * This function registers device with input core. The device must be 1355 * allocated with input_allocate_device() and all it's capabilities 1356 * set up before registering. 1357 * If function fails the device must be freed with input_free_device(). 1358 * Once device has been successfully registered it can be unregistered 1359 * with input_unregister_device(); input_free_device() should not be 1360 * called in this case. 1361 */ 1362 int input_register_device(struct input_dev *dev) 1363 { 1364 static atomic_t input_no = ATOMIC_INIT(0); 1365 struct input_handler *handler; 1366 const char *path; 1367 int error; 1368 1369 __set_bit(EV_SYN, dev->evbit); 1370 1371 /* 1372 * If delay and period are pre-set by the driver, then autorepeating 1373 * is handled by the driver itself and we don't do it in input.c. 1374 */ 1375 1376 init_timer(&dev->timer); 1377 if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) { 1378 dev->timer.data = (long) dev; 1379 dev->timer.function = input_repeat_key; 1380 dev->rep[REP_DELAY] = 250; 1381 dev->rep[REP_PERIOD] = 33; 1382 } 1383 1384 if (!dev->getkeycode) 1385 dev->getkeycode = input_default_getkeycode; 1386 1387 if (!dev->setkeycode) 1388 dev->setkeycode = input_default_setkeycode; 1389 1390 dev_set_name(&dev->dev, "input%ld", 1391 (unsigned long) atomic_inc_return(&input_no) - 1); 1392 1393 error = device_add(&dev->dev); 1394 if (error) 1395 return error; 1396 1397 path = kobject_get_path(&dev->dev.kobj, GFP_KERNEL); 1398 printk(KERN_INFO "input: %s as %s\n", 1399 dev->name ? dev->name : "Unspecified device", path ? path : "N/A"); 1400 kfree(path); 1401 1402 error = mutex_lock_interruptible(&input_mutex); 1403 if (error) { 1404 device_del(&dev->dev); 1405 return error; 1406 } 1407 1408 list_add_tail(&dev->node, &input_dev_list); 1409 1410 list_for_each_entry(handler, &input_handler_list, node) 1411 input_attach_handler(dev, handler); 1412 1413 input_wakeup_procfs_readers(); 1414 1415 mutex_unlock(&input_mutex); 1416 1417 return 0; 1418 } 1419 EXPORT_SYMBOL(input_register_device); 1420 1421 /** 1422 * input_unregister_device - unregister previously registered device 1423 * @dev: device to be unregistered 1424 * 1425 * This function unregisters an input device. Once device is unregistered 1426 * the caller should not try to access it as it may get freed at any moment. 1427 */ 1428 void input_unregister_device(struct input_dev *dev) 1429 { 1430 struct input_handle *handle, *next; 1431 1432 input_disconnect_device(dev); 1433 1434 mutex_lock(&input_mutex); 1435 1436 list_for_each_entry_safe(handle, next, &dev->h_list, d_node) 1437 handle->handler->disconnect(handle); 1438 WARN_ON(!list_empty(&dev->h_list)); 1439 1440 del_timer_sync(&dev->timer); 1441 list_del_init(&dev->node); 1442 1443 input_wakeup_procfs_readers(); 1444 1445 mutex_unlock(&input_mutex); 1446 1447 device_unregister(&dev->dev); 1448 } 1449 EXPORT_SYMBOL(input_unregister_device); 1450 1451 /** 1452 * input_register_handler - register a new input handler 1453 * @handler: handler to be registered 1454 * 1455 * This function registers a new input handler (interface) for input 1456 * devices in the system and attaches it to all input devices that 1457 * are compatible with the handler. 1458 */ 1459 int input_register_handler(struct input_handler *handler) 1460 { 1461 struct input_dev *dev; 1462 int retval; 1463 1464 retval = mutex_lock_interruptible(&input_mutex); 1465 if (retval) 1466 return retval; 1467 1468 INIT_LIST_HEAD(&handler->h_list); 1469 1470 if (handler->fops != NULL) { 1471 if (input_table[handler->minor >> 5]) { 1472 retval = -EBUSY; 1473 goto out; 1474 } 1475 input_table[handler->minor >> 5] = handler; 1476 } 1477 1478 list_add_tail(&handler->node, &input_handler_list); 1479 1480 list_for_each_entry(dev, &input_dev_list, node) 1481 input_attach_handler(dev, handler); 1482 1483 input_wakeup_procfs_readers(); 1484 1485 out: 1486 mutex_unlock(&input_mutex); 1487 return retval; 1488 } 1489 EXPORT_SYMBOL(input_register_handler); 1490 1491 /** 1492 * input_unregister_handler - unregisters an input handler 1493 * @handler: handler to be unregistered 1494 * 1495 * This function disconnects a handler from its input devices and 1496 * removes it from lists of known handlers. 1497 */ 1498 void input_unregister_handler(struct input_handler *handler) 1499 { 1500 struct input_handle *handle, *next; 1501 1502 mutex_lock(&input_mutex); 1503 1504 list_for_each_entry_safe(handle, next, &handler->h_list, h_node) 1505 handler->disconnect(handle); 1506 WARN_ON(!list_empty(&handler->h_list)); 1507 1508 list_del_init(&handler->node); 1509 1510 if (handler->fops != NULL) 1511 input_table[handler->minor >> 5] = NULL; 1512 1513 input_wakeup_procfs_readers(); 1514 1515 mutex_unlock(&input_mutex); 1516 } 1517 EXPORT_SYMBOL(input_unregister_handler); 1518 1519 /** 1520 * input_register_handle - register a new input handle 1521 * @handle: handle to register 1522 * 1523 * This function puts a new input handle onto device's 1524 * and handler's lists so that events can flow through 1525 * it once it is opened using input_open_device(). 1526 * 1527 * This function is supposed to be called from handler's 1528 * connect() method. 1529 */ 1530 int input_register_handle(struct input_handle *handle) 1531 { 1532 struct input_handler *handler = handle->handler; 1533 struct input_dev *dev = handle->dev; 1534 int error; 1535 1536 /* 1537 * We take dev->mutex here to prevent race with 1538 * input_release_device(). 1539 */ 1540 error = mutex_lock_interruptible(&dev->mutex); 1541 if (error) 1542 return error; 1543 list_add_tail_rcu(&handle->d_node, &dev->h_list); 1544 mutex_unlock(&dev->mutex); 1545 synchronize_rcu(); 1546 1547 /* 1548 * Since we are supposed to be called from ->connect() 1549 * which is mutually exclusive with ->disconnect() 1550 * we can't be racing with input_unregister_handle() 1551 * and so separate lock is not needed here. 1552 */ 1553 list_add_tail(&handle->h_node, &handler->h_list); 1554 1555 if (handler->start) 1556 handler->start(handle); 1557 1558 return 0; 1559 } 1560 EXPORT_SYMBOL(input_register_handle); 1561 1562 /** 1563 * input_unregister_handle - unregister an input handle 1564 * @handle: handle to unregister 1565 * 1566 * This function removes input handle from device's 1567 * and handler's lists. 1568 * 1569 * This function is supposed to be called from handler's 1570 * disconnect() method. 1571 */ 1572 void input_unregister_handle(struct input_handle *handle) 1573 { 1574 struct input_dev *dev = handle->dev; 1575 1576 list_del_init(&handle->h_node); 1577 1578 /* 1579 * Take dev->mutex to prevent race with input_release_device(). 1580 */ 1581 mutex_lock(&dev->mutex); 1582 list_del_rcu(&handle->d_node); 1583 mutex_unlock(&dev->mutex); 1584 synchronize_rcu(); 1585 } 1586 EXPORT_SYMBOL(input_unregister_handle); 1587 1588 static int input_open_file(struct inode *inode, struct file *file) 1589 { 1590 struct input_handler *handler; 1591 const struct file_operations *old_fops, *new_fops = NULL; 1592 int err; 1593 1594 lock_kernel(); 1595 /* No load-on-demand here? */ 1596 handler = input_table[iminor(inode) >> 5]; 1597 if (!handler || !(new_fops = fops_get(handler->fops))) { 1598 err = -ENODEV; 1599 goto out; 1600 } 1601 1602 /* 1603 * That's _really_ odd. Usually NULL ->open means "nothing special", 1604 * not "no device". Oh, well... 1605 */ 1606 if (!new_fops->open) { 1607 fops_put(new_fops); 1608 err = -ENODEV; 1609 goto out; 1610 } 1611 old_fops = file->f_op; 1612 file->f_op = new_fops; 1613 1614 err = new_fops->open(inode, file); 1615 1616 if (err) { 1617 fops_put(file->f_op); 1618 file->f_op = fops_get(old_fops); 1619 } 1620 fops_put(old_fops); 1621 out: 1622 unlock_kernel(); 1623 return err; 1624 } 1625 1626 static const struct file_operations input_fops = { 1627 .owner = THIS_MODULE, 1628 .open = input_open_file, 1629 }; 1630 1631 static int __init input_init(void) 1632 { 1633 int err; 1634 1635 err = class_register(&input_class); 1636 if (err) { 1637 printk(KERN_ERR "input: unable to register input_dev class\n"); 1638 return err; 1639 } 1640 1641 err = input_proc_init(); 1642 if (err) 1643 goto fail1; 1644 1645 err = register_chrdev(INPUT_MAJOR, "input", &input_fops); 1646 if (err) { 1647 printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR); 1648 goto fail2; 1649 } 1650 1651 return 0; 1652 1653 fail2: input_proc_exit(); 1654 fail1: class_unregister(&input_class); 1655 return err; 1656 } 1657 1658 static void __exit input_exit(void) 1659 { 1660 input_proc_exit(); 1661 unregister_chrdev(INPUT_MAJOR, "input"); 1662 class_unregister(&input_class); 1663 } 1664 1665 subsys_initcall(input_init); 1666 module_exit(input_exit); 1667