1 /* 2 * drivers/extcon/extcon.c - External Connector (extcon) framework. 3 * 4 * External connector (extcon) class driver 5 * 6 * Copyright (C) 2015 Samsung Electronics 7 * Author: Chanwoo Choi <cw00.choi@samsung.com> 8 * 9 * Copyright (C) 2012 Samsung Electronics 10 * Author: Donggeun Kim <dg77.kim@samsung.com> 11 * Author: MyungJoo Ham <myungjoo.ham@samsung.com> 12 * 13 * based on android/drivers/switch/switch_class.c 14 * Copyright (C) 2008 Google, Inc. 15 * Author: Mike Lockwood <lockwood@android.com> 16 * 17 * This software is licensed under the terms of the GNU General Public 18 * License version 2, as published by the Free Software Foundation, and 19 * may be copied, distributed, and modified under those terms. 20 * 21 * This program is distributed in the hope that it will be useful, 22 * but WITHOUT ANY WARRANTY; without even the implied warranty of 23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 24 * GNU General Public License for more details. 25 */ 26 27 #include <linux/module.h> 28 #include <linux/types.h> 29 #include <linux/init.h> 30 #include <linux/device.h> 31 #include <linux/fs.h> 32 #include <linux/err.h> 33 #include <linux/extcon.h> 34 #include <linux/of.h> 35 #include <linux/slab.h> 36 #include <linux/sysfs.h> 37 38 #define SUPPORTED_CABLE_MAX 32 39 #define CABLE_NAME_MAX 30 40 41 static const char *extcon_name[] = { 42 [EXTCON_NONE] = "NONE", 43 44 /* USB external connector */ 45 [EXTCON_USB] = "USB", 46 [EXTCON_USB_HOST] = "USB-HOST", 47 48 /* Charger external connector */ 49 [EXTCON_TA] = "TA", 50 [EXTCON_FAST_CHARGER] = "FAST-CHARGER", 51 [EXTCON_SLOW_CHARGER] = "SLOW-CHARGER", 52 [EXTCON_CHARGE_DOWNSTREAM] = "CHARGE-DOWNSTREAM", 53 54 /* Audio/Video external connector */ 55 [EXTCON_LINE_IN] = "LINE-IN", 56 [EXTCON_LINE_OUT] = "LINE-OUT", 57 [EXTCON_MICROPHONE] = "MICROPHONE", 58 [EXTCON_HEADPHONE] = "HEADPHONE", 59 60 [EXTCON_HDMI] = "HDMI", 61 [EXTCON_MHL] = "MHL", 62 [EXTCON_DVI] = "DVI", 63 [EXTCON_VGA] = "VGA", 64 [EXTCON_SPDIF_IN] = "SPDIF-IN", 65 [EXTCON_SPDIF_OUT] = "SPDIF-OUT", 66 [EXTCON_VIDEO_IN] = "VIDEO-IN", 67 [EXTCON_VIDEO_OUT] = "VIDEO-OUT", 68 69 /* Etc external connector */ 70 [EXTCON_DOCK] = "DOCK", 71 [EXTCON_JIG] = "JIG", 72 [EXTCON_MECHANICAL] = "MECHANICAL", 73 74 NULL, 75 }; 76 77 static struct class *extcon_class; 78 #if defined(CONFIG_ANDROID) 79 static struct class_compat *switch_class; 80 #endif /* CONFIG_ANDROID */ 81 82 static LIST_HEAD(extcon_dev_list); 83 static DEFINE_MUTEX(extcon_dev_list_lock); 84 85 /** 86 * check_mutually_exclusive - Check if new_state violates mutually_exclusive 87 * condition. 88 * @edev: the extcon device 89 * @new_state: new cable attach status for @edev 90 * 91 * Returns 0 if nothing violates. Returns the index + 1 for the first 92 * violated condition. 93 */ 94 static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state) 95 { 96 int i = 0; 97 98 if (!edev->mutually_exclusive) 99 return 0; 100 101 for (i = 0; edev->mutually_exclusive[i]; i++) { 102 int weight; 103 u32 correspondants = new_state & edev->mutually_exclusive[i]; 104 105 /* calculate the total number of bits set */ 106 weight = hweight32(correspondants); 107 if (weight > 1) 108 return i + 1; 109 } 110 111 return 0; 112 } 113 114 static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id) 115 { 116 int i; 117 118 /* Find the the index of extcon cable in edev->supported_cable */ 119 for (i = 0; i < edev->max_supported; i++) { 120 if (edev->supported_cable[i] == id) 121 return i; 122 } 123 124 return -EINVAL; 125 } 126 127 static int find_cable_id_by_name(struct extcon_dev *edev, const char *name) 128 { 129 unsigned int id = -EINVAL; 130 int i = 0; 131 132 /* Find the id of extcon cable */ 133 while (extcon_name[i]) { 134 if (!strncmp(extcon_name[i], name, CABLE_NAME_MAX)) { 135 id = i; 136 break; 137 } 138 i++; 139 } 140 141 return id; 142 } 143 144 static int find_cable_index_by_name(struct extcon_dev *edev, const char *name) 145 { 146 unsigned int id; 147 148 if (edev->max_supported == 0) 149 return -EINVAL; 150 151 /* Find the the number of extcon cable */ 152 id = find_cable_id_by_name(edev, name); 153 if (id < 0) 154 return id; 155 156 return find_cable_index_by_id(edev, id); 157 } 158 159 static bool is_extcon_changed(u32 prev, u32 new, int idx, bool *attached) 160 { 161 if (((prev >> idx) & 0x1) != ((new >> idx) & 0x1)) { 162 *attached = new ? true : false; 163 return true; 164 } 165 166 return false; 167 } 168 169 static ssize_t state_show(struct device *dev, struct device_attribute *attr, 170 char *buf) 171 { 172 int i, count = 0; 173 struct extcon_dev *edev = dev_get_drvdata(dev); 174 175 if (edev->print_state) { 176 int ret = edev->print_state(edev, buf); 177 178 if (ret >= 0) 179 return ret; 180 /* Use default if failed */ 181 } 182 183 if (edev->max_supported == 0) 184 return sprintf(buf, "%u\n", edev->state); 185 186 for (i = 0; i < edev->max_supported; i++) { 187 count += sprintf(buf + count, "%s=%d\n", 188 extcon_name[edev->supported_cable[i]], 189 !!(edev->state & (1 << i))); 190 } 191 192 return count; 193 } 194 195 static ssize_t state_store(struct device *dev, struct device_attribute *attr, 196 const char *buf, size_t count) 197 { 198 u32 state; 199 ssize_t ret = 0; 200 struct extcon_dev *edev = dev_get_drvdata(dev); 201 202 ret = sscanf(buf, "0x%x", &state); 203 if (ret == 0) 204 ret = -EINVAL; 205 else 206 ret = extcon_set_state(edev, state); 207 208 if (ret < 0) 209 return ret; 210 211 return count; 212 } 213 static DEVICE_ATTR_RW(state); 214 215 static ssize_t name_show(struct device *dev, struct device_attribute *attr, 216 char *buf) 217 { 218 struct extcon_dev *edev = dev_get_drvdata(dev); 219 220 return sprintf(buf, "%s\n", edev->name); 221 } 222 static DEVICE_ATTR_RO(name); 223 224 static ssize_t cable_name_show(struct device *dev, 225 struct device_attribute *attr, char *buf) 226 { 227 struct extcon_cable *cable = container_of(attr, struct extcon_cable, 228 attr_name); 229 int i = cable->cable_index; 230 231 return sprintf(buf, "%s\n", 232 extcon_name[cable->edev->supported_cable[i]]); 233 } 234 235 static ssize_t cable_state_show(struct device *dev, 236 struct device_attribute *attr, char *buf) 237 { 238 struct extcon_cable *cable = container_of(attr, struct extcon_cable, 239 attr_state); 240 241 int i = cable->cable_index; 242 243 return sprintf(buf, "%d\n", 244 extcon_get_cable_state_(cable->edev, 245 cable->edev->supported_cable[i])); 246 } 247 248 /** 249 * extcon_update_state() - Update the cable attach states of the extcon device 250 * only for the masked bits. 251 * @edev: the extcon device 252 * @mask: the bit mask to designate updated bits. 253 * @state: new cable attach status for @edev 254 * 255 * Changing the state sends uevent with environment variable containing 256 * the name of extcon device (envp[0]) and the state output (envp[1]). 257 * Tizen uses this format for extcon device to get events from ports. 258 * Android uses this format as well. 259 * 260 * Note that the notifier provides which bits are changed in the state 261 * variable with the val parameter (second) to the callback. 262 */ 263 int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state) 264 { 265 char name_buf[120]; 266 char state_buf[120]; 267 char *prop_buf; 268 char *envp[3]; 269 int env_offset = 0; 270 int length; 271 int index; 272 unsigned long flags; 273 bool attached; 274 275 spin_lock_irqsave(&edev->lock, flags); 276 277 if (edev->state != ((edev->state & ~mask) | (state & mask))) { 278 u32 old_state; 279 280 if (check_mutually_exclusive(edev, (edev->state & ~mask) | 281 (state & mask))) { 282 spin_unlock_irqrestore(&edev->lock, flags); 283 return -EPERM; 284 } 285 286 old_state = edev->state; 287 edev->state &= ~mask; 288 edev->state |= state & mask; 289 290 for (index = 0; index < edev->max_supported; index++) { 291 if (is_extcon_changed(old_state, edev->state, index, 292 &attached)) 293 raw_notifier_call_chain(&edev->nh[index], 294 attached, edev); 295 } 296 297 /* This could be in interrupt handler */ 298 prop_buf = (char *)get_zeroed_page(GFP_ATOMIC); 299 if (prop_buf) { 300 length = name_show(&edev->dev, NULL, prop_buf); 301 if (length > 0) { 302 if (prop_buf[length - 1] == '\n') 303 prop_buf[length - 1] = 0; 304 snprintf(name_buf, sizeof(name_buf), 305 "NAME=%s", prop_buf); 306 envp[env_offset++] = name_buf; 307 } 308 length = state_show(&edev->dev, NULL, prop_buf); 309 if (length > 0) { 310 if (prop_buf[length - 1] == '\n') 311 prop_buf[length - 1] = 0; 312 snprintf(state_buf, sizeof(state_buf), 313 "STATE=%s", prop_buf); 314 envp[env_offset++] = state_buf; 315 } 316 envp[env_offset] = NULL; 317 /* Unlock early before uevent */ 318 spin_unlock_irqrestore(&edev->lock, flags); 319 320 kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp); 321 free_page((unsigned long)prop_buf); 322 } else { 323 /* Unlock early before uevent */ 324 spin_unlock_irqrestore(&edev->lock, flags); 325 326 dev_err(&edev->dev, "out of memory in extcon_set_state\n"); 327 kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE); 328 } 329 } else { 330 /* No changes */ 331 spin_unlock_irqrestore(&edev->lock, flags); 332 } 333 334 return 0; 335 } 336 EXPORT_SYMBOL_GPL(extcon_update_state); 337 338 /** 339 * extcon_set_state() - Set the cable attach states of the extcon device. 340 * @edev: the extcon device 341 * @state: new cable attach status for @edev 342 * 343 * Note that notifier provides which bits are changed in the state 344 * variable with the val parameter (second) to the callback. 345 */ 346 int extcon_set_state(struct extcon_dev *edev, u32 state) 347 { 348 return extcon_update_state(edev, 0xffffffff, state); 349 } 350 EXPORT_SYMBOL_GPL(extcon_set_state); 351 352 /** 353 * extcon_get_cable_state_() - Get the status of a specific cable. 354 * @edev: the extcon device that has the cable. 355 * @id: the unique id of each external connector in extcon enumeration. 356 */ 357 int extcon_get_cable_state_(struct extcon_dev *edev, const unsigned int id) 358 { 359 int index; 360 361 index = find_cable_index_by_id(edev, id); 362 if (index < 0) 363 return index; 364 365 if (edev->max_supported && edev->max_supported <= index) 366 return -EINVAL; 367 368 return !!(edev->state & (1 << index)); 369 } 370 EXPORT_SYMBOL_GPL(extcon_get_cable_state_); 371 372 /** 373 * extcon_get_cable_state() - Get the status of a specific cable. 374 * @edev: the extcon device that has the cable. 375 * @cable_name: cable name. 376 * 377 * Note that this is slower than extcon_get_cable_state_. 378 */ 379 int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name) 380 { 381 unsigned int id; 382 383 id = find_cable_id_by_name(edev, cable_name); 384 if (id < 0) 385 return id; 386 387 return extcon_get_cable_state_(edev, id); 388 } 389 EXPORT_SYMBOL_GPL(extcon_get_cable_state); 390 391 /** 392 * extcon_set_cable_state_() - Set the status of a specific cable. 393 * @edev: the extcon device that has the cable. 394 * @id: the unique id of each external connector 395 * in extcon enumeration. 396 * @state: the new cable status. The default semantics is 397 * true: attached / false: detached. 398 */ 399 int extcon_set_cable_state_(struct extcon_dev *edev, unsigned int id, 400 bool cable_state) 401 { 402 u32 state; 403 int index; 404 405 index = find_cable_index_by_id(edev, id); 406 if (index < 0) 407 return index; 408 409 if (edev->max_supported && edev->max_supported <= index) 410 return -EINVAL; 411 412 state = cable_state ? (1 << index) : 0; 413 return extcon_update_state(edev, 1 << index, state); 414 } 415 EXPORT_SYMBOL_GPL(extcon_set_cable_state_); 416 417 /** 418 * extcon_set_cable_state() - Set the status of a specific cable. 419 * @edev: the extcon device that has the cable. 420 * @cable_name: cable name. 421 * @cable_state: the new cable status. The default semantics is 422 * true: attached / false: detached. 423 * 424 * Note that this is slower than extcon_set_cable_state_. 425 */ 426 int extcon_set_cable_state(struct extcon_dev *edev, 427 const char *cable_name, bool cable_state) 428 { 429 unsigned int id; 430 431 id = find_cable_id_by_name(edev, cable_name); 432 if (id < 0) 433 return id; 434 435 return extcon_set_cable_state_(edev, id, cable_state); 436 } 437 EXPORT_SYMBOL_GPL(extcon_set_cable_state); 438 439 /** 440 * extcon_get_extcon_dev() - Get the extcon device instance from the name 441 * @extcon_name: The extcon name provided with extcon_dev_register() 442 */ 443 struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name) 444 { 445 struct extcon_dev *sd; 446 447 mutex_lock(&extcon_dev_list_lock); 448 list_for_each_entry(sd, &extcon_dev_list, entry) { 449 if (!strcmp(sd->name, extcon_name)) 450 goto out; 451 } 452 sd = NULL; 453 out: 454 mutex_unlock(&extcon_dev_list_lock); 455 return sd; 456 } 457 EXPORT_SYMBOL_GPL(extcon_get_extcon_dev); 458 459 /** 460 * extcon_register_interest() - Register a notifier for a state change of a 461 * specific cable, not an entier set of cables of a 462 * extcon device. 463 * @obj: an empty extcon_specific_cable_nb object to be returned. 464 * @extcon_name: the name of extcon device. 465 * if NULL, extcon_register_interest will register 466 * every cable with the target cable_name given. 467 * @cable_name: the target cable name. 468 * @nb: the notifier block to get notified. 469 * 470 * Provide an empty extcon_specific_cable_nb. extcon_register_interest() sets 471 * the struct for you. 472 * 473 * extcon_register_interest is a helper function for those who want to get 474 * notification for a single specific cable's status change. If a user wants 475 * to get notification for any changes of all cables of a extcon device, 476 * he/she should use the general extcon_register_notifier(). 477 * 478 * Note that the second parameter given to the callback of nb (val) is 479 * "old_state", not the current state. The current state can be retrieved 480 * by looking at the third pameter (edev pointer)'s state value. 481 */ 482 int extcon_register_interest(struct extcon_specific_cable_nb *obj, 483 const char *extcon_name, const char *cable_name, 484 struct notifier_block *nb) 485 { 486 unsigned long flags; 487 int ret; 488 489 if (!obj || !cable_name || !nb) 490 return -EINVAL; 491 492 if (extcon_name) { 493 obj->edev = extcon_get_extcon_dev(extcon_name); 494 if (!obj->edev) 495 return -ENODEV; 496 497 obj->cable_index = find_cable_index_by_name(obj->edev, 498 cable_name); 499 if (obj->cable_index < 0) 500 return obj->cable_index; 501 502 obj->user_nb = nb; 503 504 spin_lock_irqsave(&obj->edev->lock, flags); 505 ret = raw_notifier_chain_register( 506 &obj->edev->nh[obj->cable_index], 507 obj->user_nb); 508 spin_unlock_irqrestore(&obj->edev->lock, flags); 509 } else { 510 struct class_dev_iter iter; 511 struct extcon_dev *extd; 512 struct device *dev; 513 514 if (!extcon_class) 515 return -ENODEV; 516 class_dev_iter_init(&iter, extcon_class, NULL, NULL); 517 while ((dev = class_dev_iter_next(&iter))) { 518 extd = dev_get_drvdata(dev); 519 520 if (find_cable_index_by_name(extd, cable_name) < 0) 521 continue; 522 523 class_dev_iter_exit(&iter); 524 return extcon_register_interest(obj, extd->name, 525 cable_name, nb); 526 } 527 528 ret = -ENODEV; 529 } 530 531 return ret; 532 } 533 EXPORT_SYMBOL_GPL(extcon_register_interest); 534 535 /** 536 * extcon_unregister_interest() - Unregister the notifier registered by 537 * extcon_register_interest(). 538 * @obj: the extcon_specific_cable_nb object returned by 539 * extcon_register_interest(). 540 */ 541 int extcon_unregister_interest(struct extcon_specific_cable_nb *obj) 542 { 543 unsigned long flags; 544 int ret; 545 546 if (!obj) 547 return -EINVAL; 548 549 spin_lock_irqsave(&obj->edev->lock, flags); 550 ret = raw_notifier_chain_unregister( 551 &obj->edev->nh[obj->cable_index], obj->user_nb); 552 spin_unlock_irqrestore(&obj->edev->lock, flags); 553 554 return ret; 555 } 556 EXPORT_SYMBOL_GPL(extcon_unregister_interest); 557 558 /** 559 * extcon_register_notifier() - Register a notifiee to get notified by 560 * any attach status changes from the extcon. 561 * @edev: the extcon device that has the external connecotr. 562 * @id: the unique id of each external connector in extcon enumeration. 563 * @nb: a notifier block to be registered. 564 * 565 * Note that the second parameter given to the callback of nb (val) is 566 * "old_state", not the current state. The current state can be retrieved 567 * by looking at the third pameter (edev pointer)'s state value. 568 */ 569 int extcon_register_notifier(struct extcon_dev *edev, unsigned int id, 570 struct notifier_block *nb) 571 { 572 unsigned long flags; 573 int ret, idx; 574 575 idx = find_cable_index_by_id(edev, id); 576 577 spin_lock_irqsave(&edev->lock, flags); 578 ret = raw_notifier_chain_register(&edev->nh[idx], nb); 579 spin_unlock_irqrestore(&edev->lock, flags); 580 581 return ret; 582 } 583 EXPORT_SYMBOL_GPL(extcon_register_notifier); 584 585 /** 586 * extcon_unregister_notifier() - Unregister a notifiee from the extcon device. 587 * @edev: the extcon device that has the external connecotr. 588 * @id: the unique id of each external connector in extcon enumeration. 589 * @nb: a notifier block to be registered. 590 */ 591 int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id, 592 struct notifier_block *nb) 593 { 594 unsigned long flags; 595 int ret, idx; 596 597 idx = find_cable_index_by_id(edev, id); 598 599 spin_lock_irqsave(&edev->lock, flags); 600 ret = raw_notifier_chain_unregister(&edev->nh[idx], nb); 601 spin_unlock_irqrestore(&edev->lock, flags); 602 603 return ret; 604 } 605 EXPORT_SYMBOL_GPL(extcon_unregister_notifier); 606 607 static struct attribute *extcon_attrs[] = { 608 &dev_attr_state.attr, 609 &dev_attr_name.attr, 610 NULL, 611 }; 612 ATTRIBUTE_GROUPS(extcon); 613 614 static int create_extcon_class(void) 615 { 616 if (!extcon_class) { 617 extcon_class = class_create(THIS_MODULE, "extcon"); 618 if (IS_ERR(extcon_class)) 619 return PTR_ERR(extcon_class); 620 extcon_class->dev_groups = extcon_groups; 621 622 #if defined(CONFIG_ANDROID) 623 switch_class = class_compat_register("switch"); 624 if (WARN(!switch_class, "cannot allocate")) 625 return -ENOMEM; 626 #endif /* CONFIG_ANDROID */ 627 } 628 629 return 0; 630 } 631 632 static void extcon_dev_release(struct device *dev) 633 { 634 } 635 636 static const char *muex_name = "mutually_exclusive"; 637 static void dummy_sysfs_dev_release(struct device *dev) 638 { 639 } 640 641 /* 642 * extcon_dev_allocate() - Allocate the memory of extcon device. 643 * @supported_cable: Array of supported extcon ending with EXTCON_NONE. 644 * If supported_cable is NULL, cable name related APIs 645 * are disabled. 646 * 647 * This function allocates the memory for extcon device without allocating 648 * memory in each extcon provider driver and initialize default setting for 649 * extcon device. 650 * 651 * Return the pointer of extcon device if success or ERR_PTR(err) if fail 652 */ 653 struct extcon_dev *extcon_dev_allocate(const unsigned int *supported_cable) 654 { 655 struct extcon_dev *edev; 656 657 edev = kzalloc(sizeof(*edev), GFP_KERNEL); 658 if (!edev) 659 return ERR_PTR(-ENOMEM); 660 661 edev->max_supported = 0; 662 edev->supported_cable = supported_cable; 663 664 return edev; 665 } 666 667 /* 668 * extcon_dev_free() - Free the memory of extcon device. 669 * @edev: the extcon device to free 670 */ 671 void extcon_dev_free(struct extcon_dev *edev) 672 { 673 kfree(edev); 674 } 675 EXPORT_SYMBOL_GPL(extcon_dev_free); 676 677 static int devm_extcon_dev_match(struct device *dev, void *res, void *data) 678 { 679 struct extcon_dev **r = res; 680 681 if (WARN_ON(!r || !*r)) 682 return 0; 683 684 return *r == data; 685 } 686 687 static void devm_extcon_dev_release(struct device *dev, void *res) 688 { 689 extcon_dev_free(*(struct extcon_dev **)res); 690 } 691 692 /** 693 * devm_extcon_dev_allocate - Allocate managed extcon device 694 * @dev: device owning the extcon device being created 695 * @supported_cable: Array of supported extcon ending with EXTCON_NONE. 696 * If supported_cable is NULL, cable name related APIs 697 * are disabled. 698 * 699 * This function manages automatically the memory of extcon device using device 700 * resource management and simplify the control of freeing the memory of extcon 701 * device. 702 * 703 * Returns the pointer memory of allocated extcon_dev if success 704 * or ERR_PTR(err) if fail 705 */ 706 struct extcon_dev *devm_extcon_dev_allocate(struct device *dev, 707 const unsigned int *supported_cable) 708 { 709 struct extcon_dev **ptr, *edev; 710 711 ptr = devres_alloc(devm_extcon_dev_release, sizeof(*ptr), GFP_KERNEL); 712 if (!ptr) 713 return ERR_PTR(-ENOMEM); 714 715 edev = extcon_dev_allocate(supported_cable); 716 if (IS_ERR(edev)) { 717 devres_free(ptr); 718 return edev; 719 } 720 721 edev->dev.parent = dev; 722 723 *ptr = edev; 724 devres_add(dev, ptr); 725 726 return edev; 727 } 728 EXPORT_SYMBOL_GPL(devm_extcon_dev_allocate); 729 730 void devm_extcon_dev_free(struct device *dev, struct extcon_dev *edev) 731 { 732 WARN_ON(devres_release(dev, devm_extcon_dev_release, 733 devm_extcon_dev_match, edev)); 734 } 735 EXPORT_SYMBOL_GPL(devm_extcon_dev_free); 736 737 /** 738 * extcon_dev_register() - Register a new extcon device 739 * @edev : the new extcon device (should be allocated before calling) 740 * 741 * Among the members of edev struct, please set the "user initializing data" 742 * in any case and set the "optional callbacks" if required. However, please 743 * do not set the values of "internal data", which are initialized by 744 * this function. 745 */ 746 int extcon_dev_register(struct extcon_dev *edev) 747 { 748 int ret, index = 0; 749 static atomic_t edev_no = ATOMIC_INIT(-1); 750 751 if (!extcon_class) { 752 ret = create_extcon_class(); 753 if (ret < 0) 754 return ret; 755 } 756 757 if (!edev->supported_cable) 758 return -EINVAL; 759 760 for (; edev->supported_cable[index] != EXTCON_NONE; index++); 761 762 edev->max_supported = index; 763 if (index > SUPPORTED_CABLE_MAX) { 764 dev_err(&edev->dev, 765 "exceed the maximum number of supported cables\n"); 766 return -EINVAL; 767 } 768 769 edev->dev.class = extcon_class; 770 edev->dev.release = extcon_dev_release; 771 772 edev->name = dev_name(edev->dev.parent); 773 if (IS_ERR_OR_NULL(edev->name)) { 774 dev_err(&edev->dev, 775 "extcon device name is null\n"); 776 return -EINVAL; 777 } 778 dev_set_name(&edev->dev, "extcon%lu", 779 (unsigned long)atomic_inc_return(&edev_no)); 780 781 if (edev->max_supported) { 782 char buf[10]; 783 char *str; 784 struct extcon_cable *cable; 785 786 edev->cables = kzalloc(sizeof(struct extcon_cable) * 787 edev->max_supported, GFP_KERNEL); 788 if (!edev->cables) { 789 ret = -ENOMEM; 790 goto err_sysfs_alloc; 791 } 792 for (index = 0; index < edev->max_supported; index++) { 793 cable = &edev->cables[index]; 794 795 snprintf(buf, 10, "cable.%d", index); 796 str = kzalloc(sizeof(char) * (strlen(buf) + 1), 797 GFP_KERNEL); 798 if (!str) { 799 for (index--; index >= 0; index--) { 800 cable = &edev->cables[index]; 801 kfree(cable->attr_g.name); 802 } 803 ret = -ENOMEM; 804 805 goto err_alloc_cables; 806 } 807 strcpy(str, buf); 808 809 cable->edev = edev; 810 cable->cable_index = index; 811 cable->attrs[0] = &cable->attr_name.attr; 812 cable->attrs[1] = &cable->attr_state.attr; 813 cable->attrs[2] = NULL; 814 cable->attr_g.name = str; 815 cable->attr_g.attrs = cable->attrs; 816 817 sysfs_attr_init(&cable->attr_name.attr); 818 cable->attr_name.attr.name = "name"; 819 cable->attr_name.attr.mode = 0444; 820 cable->attr_name.show = cable_name_show; 821 822 sysfs_attr_init(&cable->attr_state.attr); 823 cable->attr_state.attr.name = "state"; 824 cable->attr_state.attr.mode = 0444; 825 cable->attr_state.show = cable_state_show; 826 } 827 } 828 829 if (edev->max_supported && edev->mutually_exclusive) { 830 char buf[80]; 831 char *name; 832 833 /* Count the size of mutually_exclusive array */ 834 for (index = 0; edev->mutually_exclusive[index]; index++) 835 ; 836 837 edev->attrs_muex = kzalloc(sizeof(struct attribute *) * 838 (index + 1), GFP_KERNEL); 839 if (!edev->attrs_muex) { 840 ret = -ENOMEM; 841 goto err_muex; 842 } 843 844 edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) * 845 index, GFP_KERNEL); 846 if (!edev->d_attrs_muex) { 847 ret = -ENOMEM; 848 kfree(edev->attrs_muex); 849 goto err_muex; 850 } 851 852 for (index = 0; edev->mutually_exclusive[index]; index++) { 853 sprintf(buf, "0x%x", edev->mutually_exclusive[index]); 854 name = kzalloc(sizeof(char) * (strlen(buf) + 1), 855 GFP_KERNEL); 856 if (!name) { 857 for (index--; index >= 0; index--) { 858 kfree(edev->d_attrs_muex[index].attr. 859 name); 860 } 861 kfree(edev->d_attrs_muex); 862 kfree(edev->attrs_muex); 863 ret = -ENOMEM; 864 goto err_muex; 865 } 866 strcpy(name, buf); 867 sysfs_attr_init(&edev->d_attrs_muex[index].attr); 868 edev->d_attrs_muex[index].attr.name = name; 869 edev->d_attrs_muex[index].attr.mode = 0000; 870 edev->attrs_muex[index] = &edev->d_attrs_muex[index] 871 .attr; 872 } 873 edev->attr_g_muex.name = muex_name; 874 edev->attr_g_muex.attrs = edev->attrs_muex; 875 876 } 877 878 if (edev->max_supported) { 879 edev->extcon_dev_type.groups = 880 kzalloc(sizeof(struct attribute_group *) * 881 (edev->max_supported + 2), GFP_KERNEL); 882 if (!edev->extcon_dev_type.groups) { 883 ret = -ENOMEM; 884 goto err_alloc_groups; 885 } 886 887 edev->extcon_dev_type.name = dev_name(&edev->dev); 888 edev->extcon_dev_type.release = dummy_sysfs_dev_release; 889 890 for (index = 0; index < edev->max_supported; index++) 891 edev->extcon_dev_type.groups[index] = 892 &edev->cables[index].attr_g; 893 if (edev->mutually_exclusive) 894 edev->extcon_dev_type.groups[index] = 895 &edev->attr_g_muex; 896 897 edev->dev.type = &edev->extcon_dev_type; 898 } 899 900 ret = device_register(&edev->dev); 901 if (ret) { 902 put_device(&edev->dev); 903 goto err_dev; 904 } 905 #if defined(CONFIG_ANDROID) 906 if (switch_class) 907 ret = class_compat_create_link(switch_class, &edev->dev, NULL); 908 #endif /* CONFIG_ANDROID */ 909 910 spin_lock_init(&edev->lock); 911 912 edev->nh = devm_kzalloc(&edev->dev, 913 sizeof(*edev->nh) * edev->max_supported, GFP_KERNEL); 914 if (!edev->nh) { 915 ret = -ENOMEM; 916 goto err_dev; 917 } 918 919 for (index = 0; index < edev->max_supported; index++) 920 RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]); 921 922 dev_set_drvdata(&edev->dev, edev); 923 edev->state = 0; 924 925 mutex_lock(&extcon_dev_list_lock); 926 list_add(&edev->entry, &extcon_dev_list); 927 mutex_unlock(&extcon_dev_list_lock); 928 929 return 0; 930 931 err_dev: 932 if (edev->max_supported) 933 kfree(edev->extcon_dev_type.groups); 934 err_alloc_groups: 935 if (edev->max_supported && edev->mutually_exclusive) { 936 for (index = 0; edev->mutually_exclusive[index]; index++) 937 kfree(edev->d_attrs_muex[index].attr.name); 938 kfree(edev->d_attrs_muex); 939 kfree(edev->attrs_muex); 940 } 941 err_muex: 942 for (index = 0; index < edev->max_supported; index++) 943 kfree(edev->cables[index].attr_g.name); 944 err_alloc_cables: 945 if (edev->max_supported) 946 kfree(edev->cables); 947 err_sysfs_alloc: 948 return ret; 949 } 950 EXPORT_SYMBOL_GPL(extcon_dev_register); 951 952 /** 953 * extcon_dev_unregister() - Unregister the extcon device. 954 * @edev: the extcon device instance to be unregistered. 955 * 956 * Note that this does not call kfree(edev) because edev was not allocated 957 * by this class. 958 */ 959 void extcon_dev_unregister(struct extcon_dev *edev) 960 { 961 int index; 962 963 mutex_lock(&extcon_dev_list_lock); 964 list_del(&edev->entry); 965 mutex_unlock(&extcon_dev_list_lock); 966 967 if (IS_ERR_OR_NULL(get_device(&edev->dev))) { 968 dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n", 969 dev_name(&edev->dev)); 970 return; 971 } 972 973 device_unregister(&edev->dev); 974 975 if (edev->mutually_exclusive && edev->max_supported) { 976 for (index = 0; edev->mutually_exclusive[index]; 977 index++) 978 kfree(edev->d_attrs_muex[index].attr.name); 979 kfree(edev->d_attrs_muex); 980 kfree(edev->attrs_muex); 981 } 982 983 for (index = 0; index < edev->max_supported; index++) 984 kfree(edev->cables[index].attr_g.name); 985 986 if (edev->max_supported) { 987 kfree(edev->extcon_dev_type.groups); 988 kfree(edev->cables); 989 } 990 991 #if defined(CONFIG_ANDROID) 992 if (switch_class) 993 class_compat_remove_link(switch_class, &edev->dev, NULL); 994 #endif 995 put_device(&edev->dev); 996 } 997 EXPORT_SYMBOL_GPL(extcon_dev_unregister); 998 999 static void devm_extcon_dev_unreg(struct device *dev, void *res) 1000 { 1001 extcon_dev_unregister(*(struct extcon_dev **)res); 1002 } 1003 1004 /** 1005 * devm_extcon_dev_register() - Resource-managed extcon_dev_register() 1006 * @dev: device to allocate extcon device 1007 * @edev: the new extcon device to register 1008 * 1009 * Managed extcon_dev_register() function. If extcon device is attached with 1010 * this function, that extcon device is automatically unregistered on driver 1011 * detach. Internally this function calls extcon_dev_register() function. 1012 * To get more information, refer that function. 1013 * 1014 * If extcon device is registered with this function and the device needs to be 1015 * unregistered separately, devm_extcon_dev_unregister() should be used. 1016 * 1017 * Returns 0 if success or negaive error number if failure. 1018 */ 1019 int devm_extcon_dev_register(struct device *dev, struct extcon_dev *edev) 1020 { 1021 struct extcon_dev **ptr; 1022 int ret; 1023 1024 ptr = devres_alloc(devm_extcon_dev_unreg, sizeof(*ptr), GFP_KERNEL); 1025 if (!ptr) 1026 return -ENOMEM; 1027 1028 ret = extcon_dev_register(edev); 1029 if (ret) { 1030 devres_free(ptr); 1031 return ret; 1032 } 1033 1034 *ptr = edev; 1035 devres_add(dev, ptr); 1036 1037 return 0; 1038 } 1039 EXPORT_SYMBOL_GPL(devm_extcon_dev_register); 1040 1041 /** 1042 * devm_extcon_dev_unregister() - Resource-managed extcon_dev_unregister() 1043 * @dev: device the extcon belongs to 1044 * @edev: the extcon device to unregister 1045 * 1046 * Unregister extcon device that is registered with devm_extcon_dev_register() 1047 * function. 1048 */ 1049 void devm_extcon_dev_unregister(struct device *dev, struct extcon_dev *edev) 1050 { 1051 WARN_ON(devres_release(dev, devm_extcon_dev_unreg, 1052 devm_extcon_dev_match, edev)); 1053 } 1054 EXPORT_SYMBOL_GPL(devm_extcon_dev_unregister); 1055 1056 #ifdef CONFIG_OF 1057 /* 1058 * extcon_get_edev_by_phandle - Get the extcon device from devicetree 1059 * @dev - instance to the given device 1060 * @index - index into list of extcon_dev 1061 * 1062 * return the instance of extcon device 1063 */ 1064 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index) 1065 { 1066 struct device_node *node; 1067 struct extcon_dev *edev; 1068 1069 if (!dev->of_node) { 1070 dev_err(dev, "device does not have a device node entry\n"); 1071 return ERR_PTR(-EINVAL); 1072 } 1073 1074 node = of_parse_phandle(dev->of_node, "extcon", index); 1075 if (!node) { 1076 dev_err(dev, "failed to get phandle in %s node\n", 1077 dev->of_node->full_name); 1078 return ERR_PTR(-ENODEV); 1079 } 1080 1081 mutex_lock(&extcon_dev_list_lock); 1082 list_for_each_entry(edev, &extcon_dev_list, entry) { 1083 if (edev->dev.parent && edev->dev.parent->of_node == node) { 1084 mutex_unlock(&extcon_dev_list_lock); 1085 return edev; 1086 } 1087 } 1088 mutex_unlock(&extcon_dev_list_lock); 1089 1090 return ERR_PTR(-EPROBE_DEFER); 1091 } 1092 #else 1093 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index) 1094 { 1095 return ERR_PTR(-ENOSYS); 1096 } 1097 #endif /* CONFIG_OF */ 1098 EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle); 1099 1100 /** 1101 * extcon_get_edev_name() - Get the name of the extcon device. 1102 * @edev: the extcon device 1103 */ 1104 const char *extcon_get_edev_name(struct extcon_dev *edev) 1105 { 1106 return !edev ? NULL : edev->name; 1107 } 1108 1109 static int __init extcon_class_init(void) 1110 { 1111 return create_extcon_class(); 1112 } 1113 module_init(extcon_class_init); 1114 1115 static void __exit extcon_class_exit(void) 1116 { 1117 #if defined(CONFIG_ANDROID) 1118 class_compat_unregister(switch_class); 1119 #endif 1120 class_destroy(extcon_class); 1121 } 1122 module_exit(extcon_class_exit); 1123 1124 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>"); 1125 MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>"); 1126 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>"); 1127 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); 1128 MODULE_DESCRIPTION("External connector (extcon) class driver"); 1129 MODULE_LICENSE("GPL"); 1130