drivers/extcon/extcon.c

   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 struct __extcon_info {
  42         unsigned int type;
  43         unsigned int id;
  44         const char *name;
  45
  46 } extcon_info[] = {
  47         [EXTCON_NONE] = {
  48                 .type = EXTCON_TYPE_MISC,
  49                 .id = EXTCON_NONE,
  50                 .name = "NONE",
  51         },
  52
  53         /* USB external connector */
  54         [EXTCON_USB] = {
  55                 .type = EXTCON_TYPE_USB,
  56                 .id = EXTCON_USB,
  57                 .name = "USB",
  58         },
  59         [EXTCON_USB_HOST] = {
  60                 .type = EXTCON_TYPE_USB,
  61                 .id = EXTCON_USB_HOST,
  62                 .name = "USB_HOST",
  63         },
  64
  65         /* Charging external connector */
  66         [EXTCON_CHG_USB_SDP] = {
  67                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  68                 .id = EXTCON_CHG_USB_SDP,
  69                 .name = "SDP",
  70         },
  71         [EXTCON_CHG_USB_DCP] = {
  72                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  73                 .id = EXTCON_CHG_USB_DCP,
  74                 .name = "DCP",
  75         },
  76         [EXTCON_CHG_USB_CDP] = {
  77                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  78                 .id = EXTCON_CHG_USB_CDP,
  79                 .name = "CDP",
  80         },
  81         [EXTCON_CHG_USB_ACA] = {
  82                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  83                 .id = EXTCON_CHG_USB_ACA,
  84                 .name = "ACA",
  85         },
  86         [EXTCON_CHG_USB_FAST] = {
  87                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  88                 .id = EXTCON_CHG_USB_FAST,
  89                 .name = "FAST-CHARGER",
  90         },
  91         [EXTCON_CHG_USB_SLOW] = {
  92                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  93                 .id = EXTCON_CHG_USB_SLOW,
  94                 .name = "SLOW-CHARGER",
  95         },
  96
  97         /* Jack external connector */
  98         [EXTCON_JACK_MICROPHONE] = {
  99                 .type = EXTCON_TYPE_JACK,
 100                 .id = EXTCON_JACK_MICROPHONE,
 101                 .name = "MICROPHONE",
 102         },
 103         [EXTCON_JACK_HEADPHONE] = {
 104                 .type = EXTCON_TYPE_JACK,
 105                 .id = EXTCON_JACK_HEADPHONE,
 106                 .name = "HEADPHONE",
 107         },
 108         [EXTCON_JACK_LINE_IN] = {
 109                 .type = EXTCON_TYPE_JACK,
 110                 .id = EXTCON_JACK_LINE_IN,
 111                 .name = "LINE-IN",
 112         },
 113         [EXTCON_JACK_LINE_OUT] = {
 114                 .type = EXTCON_TYPE_JACK,
 115                 .id = EXTCON_JACK_LINE_OUT,
 116                 .name = "LINE-OUT",
 117         },
 118         [EXTCON_JACK_VIDEO_IN] = {
 119                 .type = EXTCON_TYPE_JACK,
 120                 .id = EXTCON_JACK_VIDEO_IN,
 121                 .name = "VIDEO-IN",
 122         },
 123         [EXTCON_JACK_VIDEO_OUT] = {
 124                 .type = EXTCON_TYPE_JACK,
 125                 .id = EXTCON_JACK_VIDEO_OUT,
 126                 .name = "VIDEO-OUT",
 127         },
 128         [EXTCON_JACK_SPDIF_IN] = {
 129                 .type = EXTCON_TYPE_JACK,
 130                 .id = EXTCON_JACK_SPDIF_IN,
 131                 .name = "SPDIF-IN",
 132         },
 133         [EXTCON_JACK_SPDIF_OUT] = {
 134                 .type = EXTCON_TYPE_JACK,
 135                 .id = EXTCON_JACK_SPDIF_OUT,
 136                 .name = "SPDIF-OUT",
 137         },
 138
 139         /* Display external connector */
 140         [EXTCON_DISP_HDMI] = {
 141                 .type = EXTCON_TYPE_DISP,
 142                 .id = EXTCON_DISP_HDMI,
 143                 .name = "HDMI",
 144         },
 145         [EXTCON_DISP_MHL] = {
 146                 .type = EXTCON_TYPE_DISP,
 147                 .id = EXTCON_DISP_MHL,
 148                 .name = "MHL",
 149         },
 150         [EXTCON_DISP_DVI] = {
 151                 .type = EXTCON_TYPE_DISP,
 152                 .id = EXTCON_DISP_DVI,
 153                 .name = "DVI",
 154         },
 155         [EXTCON_DISP_VGA] = {
 156                 .type = EXTCON_TYPE_DISP,
 157                 .id = EXTCON_DISP_VGA,
 158                 .name = "VGA",
 159         },
 160         [EXTCON_DISP_DP] = {
 161                 .type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
 162                 .id = EXTCON_DISP_DP,
 163                 .name = "DP",
 164         },
 165
 166         /* Miscellaneous external connector */
 167         [EXTCON_DOCK] = {
 168                 .type = EXTCON_TYPE_MISC,
 169                 .id = EXTCON_DOCK,
 170                 .name = "DOCK",
 171         },
 172         [EXTCON_JIG] = {
 173                 .type = EXTCON_TYPE_MISC,
 174                 .id = EXTCON_JIG,
 175                 .name = "JIG",
 176         },
 177         [EXTCON_MECHANICAL] = {
 178                 .type = EXTCON_TYPE_MISC,
 179                 .id = EXTCON_MECHANICAL,
 180                 .name = "MECHANICAL",
 181         },
 182
 183         { /* sentinel */ }
 184 };
 185
 186 /**
 187  * struct extcon_cable - An internal data for each cable of extcon device.
 188  * @edev:               The extcon device
 189  * @cable_index:        Index of this cable in the edev
 190  * @attr_g:             Attribute group for the cable
 191  * @attr_name:          "name" sysfs entry
 192  * @attr_state:         "state" sysfs entry
 193  * @attrs:              Array pointing to attr_name and attr_state for attr_g
 194  */
 195 struct extcon_cable {
 196         struct extcon_dev *edev;
 197         int cable_index;
 198
 199         struct attribute_group attr_g;
 200         struct device_attribute attr_name;
 201         struct device_attribute attr_state;
 202
 203         struct attribute *attrs[3]; /* to be fed to attr_g.attrs */
 204
 205         union extcon_property_value usb_propval[EXTCON_PROP_USB_CNT];
 206         union extcon_property_value chg_propval[EXTCON_PROP_CHG_CNT];
 207         union extcon_property_value jack_propval[EXTCON_PROP_JACK_CNT];
 208         union extcon_property_value disp_propval[EXTCON_PROP_DISP_CNT];
 209
 210         unsigned long usb_bits[BITS_TO_LONGS(EXTCON_PROP_USB_CNT)];
 211         unsigned long chg_bits[BITS_TO_LONGS(EXTCON_PROP_CHG_CNT)];
 212         unsigned long jack_bits[BITS_TO_LONGS(EXTCON_PROP_JACK_CNT)];
 213         unsigned long disp_bits[BITS_TO_LONGS(EXTCON_PROP_DISP_CNT)];
 214 };
 215
 216 static struct class *extcon_class;
 217 #if defined(CONFIG_ANDROID)
 218 static struct class_compat *switch_class;
 219 #endif /* CONFIG_ANDROID */
 220
 221 static LIST_HEAD(extcon_dev_list);
 222 static DEFINE_MUTEX(extcon_dev_list_lock);
 223
 224 /**
 225  * check_mutually_exclusive - Check if new_state violates mutually_exclusive
 226  *                            condition.
 227  * @edev:       the extcon device
 228  * @new_state:  new cable attach status for @edev
 229  *
 230  * Returns 0 if nothing violates. Returns the index + 1 for the first
 231  * violated condition.
 232  */
 233 static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
 234 {
 235         int i = 0;
 236
 237         if (!edev->mutually_exclusive)
 238                 return 0;
 239
 240         for (i = 0; edev->mutually_exclusive[i]; i++) {
 241                 int weight;
 242                 u32 correspondants = new_state & edev->mutually_exclusive[i];
 243
 244                 /* calculate the total number of bits set */
 245                 weight = hweight32(correspondants);
 246                 if (weight > 1)
 247                         return i + 1;
 248         }
 249
 250         return 0;
 251 }
 252
 253 static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id)
 254 {
 255         int i;
 256
 257         /* Find the the index of extcon cable in edev->supported_cable */
 258         for (i = 0; i < edev->max_supported; i++) {
 259                 if (edev->supported_cable[i] == id)
 260                         return i;
 261         }
 262
 263         return -EINVAL;
 264 }
 265
 266 static int get_extcon_type(unsigned int prop)
 267 {
 268         switch (prop) {
 269         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 270                 return EXTCON_TYPE_USB;
 271         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 272                 return EXTCON_TYPE_CHG;
 273         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 274                 return EXTCON_TYPE_JACK;
 275         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 276                 return EXTCON_TYPE_DISP;
 277         default:
 278                 return -EINVAL;
 279         }
 280 }
 281
 282 static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index)
 283 {
 284         return !!(edev->state & BIT(index));
 285 }
 286
 287 static bool is_extcon_changed(struct extcon_dev *edev, int index,
 288                                 bool new_state)
 289 {
 290         int state = !!(edev->state & BIT(index));
 291         return (state != new_state);
 292 }
 293
 294 static bool is_extcon_property_supported(unsigned int id, unsigned int prop)
 295 {
 296         int type;
 297
 298         /* Check whether the property is supported or not. */
 299         type = get_extcon_type(prop);
 300         if (type < 0)
 301                 return false;
 302
 303         /* Check whether a specific extcon id supports the property or not. */
 304         return !!(extcon_info[id].type & type);
 305 }
 306
 307 static int is_extcon_property_capability(struct extcon_dev *edev,
 308                                 unsigned int id, int index,unsigned int prop)
 309 {
 310         struct extcon_cable *cable;
 311         int type, ret;
 312
 313         /* Check whether the property is supported or not. */
 314         type = get_extcon_type(prop);
 315         if (type < 0)
 316                 return type;
 317
 318         cable = &edev->cables[index];
 319
 320         switch (type) {
 321         case EXTCON_TYPE_USB:
 322                 ret = test_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
 323                 break;
 324         case EXTCON_TYPE_CHG:
 325                 ret = test_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
 326                 break;
 327         case EXTCON_TYPE_JACK:
 328                 ret = test_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
 329                 break;
 330         case EXTCON_TYPE_DISP:
 331                 ret = test_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
 332                 break;
 333         default:
 334                 ret = -EINVAL;
 335         }
 336
 337         return ret;
 338 }
 339
 340 static void init_property(struct extcon_dev *edev, unsigned int id, int index)
 341 {
 342         unsigned int type = extcon_info[id].type;
 343         struct extcon_cable *cable = &edev->cables[index];
 344
 345         if (EXTCON_TYPE_USB & type)
 346                 memset(cable->usb_propval, 0, sizeof(cable->usb_propval));
 347         if (EXTCON_TYPE_CHG & type)
 348                 memset(cable->chg_propval, 0, sizeof(cable->chg_propval));
 349         if (EXTCON_TYPE_JACK & type)
 350                 memset(cable->jack_propval, 0, sizeof(cable->jack_propval));
 351         if (EXTCON_TYPE_DISP & type)
 352                 memset(cable->disp_propval, 0, sizeof(cable->disp_propval));
 353 }
 354
 355 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 356                           char *buf)
 357 {
 358         int i, count = 0;
 359         struct extcon_dev *edev = dev_get_drvdata(dev);
 360
 361         if (edev->max_supported == 0)
 362                 return sprintf(buf, "%u\n", edev->state);
 363
 364         for (i = 0; i < edev->max_supported; i++) {
 365                 count += sprintf(buf + count, "%s=%d\n",
 366                                 extcon_info[edev->supported_cable[i]].name,
 367                                  !!(edev->state & (1 << i)));
 368         }
 369
 370         return count;
 371 }
 372 static DEVICE_ATTR_RO(state);
 373
 374 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 375                 char *buf)
 376 {
 377         struct extcon_dev *edev = dev_get_drvdata(dev);
 378
 379         return sprintf(buf, "%s\n", edev->name);
 380 }
 381 static DEVICE_ATTR_RO(name);
 382
 383 static ssize_t cable_name_show(struct device *dev,
 384                                struct device_attribute *attr, char *buf)
 385 {
 386         struct extcon_cable *cable = container_of(attr, struct extcon_cable,
 387                                                   attr_name);
 388         int i = cable->cable_index;
 389
 390         return sprintf(buf, "%s\n",
 391                         extcon_info[cable->edev->supported_cable[i]].name);
 392 }
 393
 394 static ssize_t cable_state_show(struct device *dev,
 395                                 struct device_attribute *attr, char *buf)
 396 {
 397         struct extcon_cable *cable = container_of(attr, struct extcon_cable,
 398                                                   attr_state);
 399
 400         int i = cable->cable_index;
 401
 402         return sprintf(buf, "%d\n",
 403                 extcon_get_state(cable->edev, cable->edev->supported_cable[i]));
 404 }
 405
 406 /**
 407  * extcon_sync()        - Synchronize the states for both the attached/detached
 408  * @edev:               the extcon device that has the cable.
 409  *
 410  * This function send a notification to synchronize the all states of a
 411  * specific external connector
 412  */
 413 int extcon_sync(struct extcon_dev *edev, unsigned int id)
 414 {
 415         char name_buf[120];
 416         char state_buf[120];
 417         char *prop_buf;
 418         char *envp[3];
 419         int env_offset = 0;
 420         int length;
 421         int index;
 422         int state;
 423         unsigned long flags;
 424
 425         if (!edev)
 426                 return -EINVAL;
 427
 428         index = find_cable_index_by_id(edev, id);
 429         if (index < 0)
 430                 return index;
 431
 432         spin_lock_irqsave(&edev->lock, flags);
 433
 434         state = !!(edev->state & BIT(index));
 435         raw_notifier_call_chain(&edev->nh[index], state, edev);
 436
 437         /* This could be in interrupt handler */
 438         prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
 439         if (!prop_buf) {
 440                 /* Unlock early before uevent */
 441                 spin_unlock_irqrestore(&edev->lock, flags);
 442
 443                 dev_err(&edev->dev, "out of memory in extcon_set_state\n");
 444                 kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE);
 445
 446                 return 0;
 447         }
 448
 449         length = name_show(&edev->dev, NULL, prop_buf);
 450         if (length > 0) {
 451                 if (prop_buf[length - 1] == '\n')
 452                         prop_buf[length - 1] = 0;
 453                 snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf);
 454                 envp[env_offset++] = name_buf;
 455         }
 456
 457         length = state_show(&edev->dev, NULL, prop_buf);
 458         if (length > 0) {
 459                 if (prop_buf[length - 1] == '\n')
 460                         prop_buf[length - 1] = 0;
 461                 snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf);
 462                 envp[env_offset++] = state_buf;
 463         }
 464         envp[env_offset] = NULL;
 465
 466         /* Unlock early before uevent */
 467         spin_unlock_irqrestore(&edev->lock, flags);
 468         kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp);
 469         free_page((unsigned long)prop_buf);
 470
 471         return 0;
 472 }
 473 EXPORT_SYMBOL_GPL(extcon_sync);
 474
 475 /**
 476  * extcon_get_state() - Get the state of a external connector.
 477  * @edev:       the extcon device that has the cable.
 478  * @id:         the unique id of each external connector in extcon enumeration.
 479  */
 480 int extcon_get_state(struct extcon_dev *edev, const unsigned int id)
 481 {
 482         int index, state;
 483         unsigned long flags;
 484
 485         if (!edev)
 486                 return -EINVAL;
 487
 488         index = find_cable_index_by_id(edev, id);
 489         if (index < 0)
 490                 return index;
 491
 492         spin_lock_irqsave(&edev->lock, flags);
 493         state = is_extcon_attached(edev, index);
 494         spin_unlock_irqrestore(&edev->lock, flags);
 495
 496         return state;
 497 }
 498 EXPORT_SYMBOL_GPL(extcon_get_state);
 499
 500 /**
 501  * extcon_set_state() - Set the state of a external connector.
 502  *                      without a notification.
 503  * @edev:               the extcon device that has the cable.
 504  * @id:                 the unique id of each external connector
 505  *                      in extcon enumeration.
 506  * @state:              the new cable status. The default semantics is
 507  *                      true: attached / false: detached.
 508  *
 509  * This function only set the state of a external connector without
 510  * a notification. To synchronize the data of a external connector,
 511  * use extcon_set_state_sync() and extcon_sync().
 512  */
 513 int extcon_set_state(struct extcon_dev *edev, unsigned int id,
 514                                 bool cable_state)
 515 {
 516         unsigned long flags;
 517         int index, ret = 0;
 518
 519         if (!edev)
 520                 return -EINVAL;
 521
 522         index = find_cable_index_by_id(edev, id);
 523         if (index < 0)
 524                 return index;
 525
 526         spin_lock_irqsave(&edev->lock, flags);
 527
 528         /* Check whether the external connector's state is changed. */
 529         if (!is_extcon_changed(edev, index, cable_state))
 530                 goto out;
 531
 532         if (check_mutually_exclusive(edev,
 533                 (edev->state & ~BIT(index)) | (cable_state & BIT(index)))) {
 534                 ret = -EPERM;
 535                 goto out;
 536         }
 537
 538         /*
 539          * Initialize the value of extcon property before setting
 540          * the detached state for an external connector.
 541          */
 542         if (!cable_state)
 543                 init_property(edev, id, index);
 544
 545         /* Update the state for a external connector. */
 546         if (cable_state)
 547                 edev->state |= BIT(index);
 548         else
 549                 edev->state &= ~(BIT(index));
 550 out:
 551         spin_unlock_irqrestore(&edev->lock, flags);
 552
 553         return ret;
 554 }
 555 EXPORT_SYMBOL_GPL(extcon_set_state);
 556
 557 /**
 558  * extcon_set_state_sync() - Set the state of a external connector
 559  *                      with a notification.
 560  * @edev:               the extcon device that has the cable.
 561  * @id:                 the unique id of each external connector
 562  *                      in extcon enumeration.
 563  * @state:              the new cable status. The default semantics is
 564  *                      true: attached / false: detached.
 565  *
 566  * This function set the state of external connector and synchronize the data
 567  * by usning a notification.
 568  */
 569 int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id,
 570                                 bool cable_state)
 571 {
 572         int ret, index;
 573         unsigned long flags;
 574
 575         index = find_cable_index_by_id(edev, id);
 576         if (index < 0)
 577                 return index;
 578
 579         /* Check whether the external connector's state is changed. */
 580         spin_lock_irqsave(&edev->lock, flags);
 581         ret = is_extcon_changed(edev, index, cable_state);
 582         spin_unlock_irqrestore(&edev->lock, flags);
 583         if (!ret)
 584                 return 0;
 585
 586         ret = extcon_set_state(edev, id, cable_state);
 587         if (ret < 0)
 588                 return ret;
 589
 590         return extcon_sync(edev, id);
 591 }
 592 EXPORT_SYMBOL_GPL(extcon_set_state_sync);
 593
 594 /**
 595  * extcon_get_property() - Get the property value of a specific cable.
 596  * @edev:               the extcon device that has the cable.
 597  * @id:                 the unique id of each external connector
 598  *                      in extcon enumeration.
 599  * @prop:               the property id among enum extcon_property.
 600  * @prop_val:           the pointer which store the value of property.
 601  *
 602  * When getting the property value of external connector, the external connector
 603  * should be attached. If detached state, function just return 0 without
 604  * property value. Also, the each property should be included in the list of
 605  * supported properties according to the type of external connectors.
 606  *
 607  * Returns 0 if success or error number if fail
 608  */
 609 int extcon_get_property(struct extcon_dev *edev, unsigned int id,
 610                                 unsigned int prop,
 611                                 union extcon_property_value *prop_val)
 612 {
 613         struct extcon_cable *cable;
 614         unsigned long flags;
 615         int index, ret = 0;
 616
 617         *prop_val = (union extcon_property_value)(0);
 618
 619         if (!edev)
 620                 return -EINVAL;
 621
 622         /* Check whether the property is supported or not */
 623         if (!is_extcon_property_supported(id, prop))
 624                 return -EINVAL;
 625
 626         /* Find the cable index of external connector by using id */
 627         index = find_cable_index_by_id(edev, id);
 628         if (index < 0)
 629                 return index;
 630
 631         spin_lock_irqsave(&edev->lock, flags);
 632
 633         /* Check whether the property is available or not. */
 634         if (!is_extcon_property_capability(edev, id, index, prop)) {
 635                 spin_unlock_irqrestore(&edev->lock, flags);
 636                 return -EPERM;
 637         }
 638
 639         /*
 640          * Check whether the external connector is attached.
 641          * If external connector is detached, the user can not
 642          * get the property value.
 643          */
 644         if (!is_extcon_attached(edev, index)) {
 645                 spin_unlock_irqrestore(&edev->lock, flags);
 646                 return 0;
 647         }
 648
 649         cable = &edev->cables[index];
 650
 651         /* Get the property value according to extcon type */
 652         switch (prop) {
 653         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 654                 *prop_val = cable->usb_propval[prop - EXTCON_PROP_USB_MIN];
 655                 break;
 656         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 657                 *prop_val = cable->chg_propval[prop - EXTCON_PROP_CHG_MIN];
 658                 break;
 659         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 660                 *prop_val = cable->jack_propval[prop - EXTCON_PROP_JACK_MIN];
 661                 break;
 662         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 663                 *prop_val = cable->disp_propval[prop - EXTCON_PROP_DISP_MIN];
 664                 break;
 665         default:
 666                 ret = -EINVAL;
 667                 break;
 668         }
 669
 670         spin_unlock_irqrestore(&edev->lock, flags);
 671
 672         return ret;
 673 }
 674 EXPORT_SYMBOL_GPL(extcon_get_property);
 675
 676 /**
 677  * extcon_set_property() - Set the property value of a specific cable.
 678  * @edev:               the extcon device that has the cable.
 679  * @id:                 the unique id of each external connector
 680  *                      in extcon enumeration.
 681  * @prop:               the property id among enum extcon_property.
 682  * @prop_val:           the pointer including the new value of property.
 683  *
 684  * The each property should be included in the list of supported properties
 685  * according to the type of external connectors.
 686  *
 687  * Returns 0 if success or error number if fail
 688  */
 689 int extcon_set_property(struct extcon_dev *edev, unsigned int id,
 690                                 unsigned int prop,
 691                                 union extcon_property_value prop_val)
 692 {
 693         struct extcon_cable *cable;
 694         unsigned long flags;
 695         int index, ret = 0;
 696
 697         if (!edev)
 698                 return -EINVAL;
 699
 700         /* Check whether the property is supported or not */
 701         if (!is_extcon_property_supported(id, prop))
 702                 return -EINVAL;
 703
 704         /* Find the cable index of external connector by using id */
 705         index = find_cable_index_by_id(edev, id);
 706         if (index < 0)
 707                 return index;
 708
 709         spin_lock_irqsave(&edev->lock, flags);
 710
 711         /* Check whether the property is available or not. */
 712         if (!is_extcon_property_capability(edev, id, index, prop)) {
 713                 spin_unlock_irqrestore(&edev->lock, flags);
 714                 return -EPERM;
 715         }
 716
 717         cable = &edev->cables[index];
 718
 719         /* Set the property value according to extcon type */
 720         switch (prop) {
 721         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 722                 cable->usb_propval[prop - EXTCON_PROP_USB_MIN] = prop_val;
 723                 break;
 724         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 725                 cable->chg_propval[prop - EXTCON_PROP_CHG_MIN] = prop_val;
 726                 break;
 727         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 728                 cable->jack_propval[prop - EXTCON_PROP_JACK_MIN] = prop_val;
 729                 break;
 730         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 731                 cable->disp_propval[prop - EXTCON_PROP_DISP_MIN] = prop_val;
 732                 break;
 733         default:
 734                 ret = -EINVAL;
 735                 break;
 736         }
 737
 738         spin_unlock_irqrestore(&edev->lock, flags);
 739
 740         return ret;
 741 }
 742 EXPORT_SYMBOL_GPL(extcon_set_property);
 743
 744 /**
 745  * extcon_set_property_sync() - Set the property value of a specific cable
 746                         with a notification.
 747  * @prop_val:           the pointer including the new value of property.
 748  *
 749  * When setting the property value of external connector, the external connector
 750  * should be attached. The each property should be included in the list of
 751  * supported properties according to the type of external connectors.
 752  *
 753  * Returns 0 if success or error number if fail
 754  */
 755 int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id,
 756                                 unsigned int prop,
 757                                 union extcon_property_value prop_val)
 758 {
 759         int ret;
 760
 761         ret = extcon_set_property(edev, id, prop, prop_val);
 762         if (ret < 0)
 763                 return ret;
 764
 765         return extcon_sync(edev, id);
 766 }
 767 EXPORT_SYMBOL_GPL(extcon_set_property_sync);
 768
 769 /**
 770  * extcon_get_property_capability() - Get the capability of property
 771  *                      of an external connector.
 772  * @edev:               the extcon device that has the cable.
 773  * @id:                 the unique id of each external connector
 774  *                      in extcon enumeration.
 775  * @prop:               the property id among enum extcon_property.
 776  *
 777  * Returns 1 if the property is available or 0 if not available.
 778  */
 779 int extcon_get_property_capability(struct extcon_dev *edev, unsigned int id,
 780                                         unsigned int prop)
 781 {
 782         int index;
 783
 784         if (!edev)
 785                 return -EINVAL;
 786
 787         /* Check whether the property is supported or not */
 788         if (!is_extcon_property_supported(id, prop))
 789                 return -EINVAL;
 790
 791         /* Find the cable index of external connector by using id */
 792         index = find_cable_index_by_id(edev, id);
 793         if (index < 0)
 794                 return index;
 795
 796         return is_extcon_property_capability(edev, id, index, prop);
 797 }
 798 EXPORT_SYMBOL_GPL(extcon_get_property_capability);
 799
 800 /**
 801  * extcon_set_property_capability() - Set the capability of a property
 802  *                      of an external connector.
 803  * @edev:               the extcon device that has the cable.
 804  * @id:                 the unique id of each external connector
 805  *                      in extcon enumeration.
 806  * @prop:               the property id among enum extcon_property.
 807  *
 808  * This function set the capability of a property for an external connector
 809  * to mark the bit in capability bitmap which mean the available state of
 810  * a property.
 811  *
 812  * Returns 0 if success or error number if fail
 813  */
 814 int extcon_set_property_capability(struct extcon_dev *edev, unsigned int id,
 815                                         unsigned int prop)
 816 {
 817         struct extcon_cable *cable;
 818         int index, type, ret = 0;
 819
 820         if (!edev)
 821                 return -EINVAL;
 822
 823         /* Check whether the property is supported or not. */
 824         if (!is_extcon_property_supported(id, prop))
 825                 return -EINVAL;
 826
 827         /* Find the cable index of external connector by using id. */
 828         index = find_cable_index_by_id(edev, id);
 829         if (index < 0)
 830                 return index;
 831
 832         type = get_extcon_type(prop);
 833         if (type < 0)
 834                 return type;
 835
 836         cable = &edev->cables[index];
 837
 838         switch (type) {
 839         case EXTCON_TYPE_USB:
 840                 __set_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
 841                 break;
 842         case EXTCON_TYPE_CHG:
 843                 __set_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
 844                 break;
 845         case EXTCON_TYPE_JACK:
 846                 __set_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
 847                 break;
 848         case EXTCON_TYPE_DISP:
 849                 __set_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
 850                 break;
 851         default:
 852                 ret = -EINVAL;
 853         }
 854
 855         return ret;
 856 }
 857 EXPORT_SYMBOL_GPL(extcon_set_property_capability);
 858
 859 /**
 860  * extcon_get_extcon_dev() - Get the extcon device instance from the name
 861  * @extcon_name:        The extcon name provided with extcon_dev_register()
 862  */
 863 struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
 864 {
 865         struct extcon_dev *sd;
 866
 867         if (!extcon_name)
 868                 return ERR_PTR(-EINVAL);
 869
 870         mutex_lock(&extcon_dev_list_lock);
 871         list_for_each_entry(sd, &extcon_dev_list, entry) {
 872                 if (!strcmp(sd->name, extcon_name))
 873                         goto out;
 874         }
 875         sd = NULL;
 876 out:
 877         mutex_unlock(&extcon_dev_list_lock);
 878         return sd;
 879 }
 880 EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
 881
 882 /**
 883  * extcon_register_notifier() - Register a notifiee to get notified by
 884  *                              any attach status changes from the extcon.
 885  * @edev:       the extcon device that has the external connecotr.
 886  * @id:         the unique id of each external connector in extcon enumeration.
 887  * @nb:         a notifier block to be registered.
 888  *
 889  * Note that the second parameter given to the callback of nb (val) is
 890  * "old_state", not the current state. The current state can be retrieved
 891  * by looking at the third pameter (edev pointer)'s state value.
 892  */
 893 int extcon_register_notifier(struct extcon_dev *edev, unsigned int id,
 894                              struct notifier_block *nb)
 895 {
 896         unsigned long flags;
 897         int ret, idx = -EINVAL;
 898
 899         if (!nb)
 900                 return -EINVAL;
 901
 902         if (edev) {
 903                 idx = find_cable_index_by_id(edev, id);
 904                 if (idx < 0)
 905                         return idx;
 906
 907                 spin_lock_irqsave(&edev->lock, flags);
 908                 ret = raw_notifier_chain_register(&edev->nh[idx], nb);
 909                 spin_unlock_irqrestore(&edev->lock, flags);
 910         } else {
 911                 struct extcon_dev *extd;
 912
 913                 mutex_lock(&extcon_dev_list_lock);
 914                 list_for_each_entry(extd, &extcon_dev_list, entry) {
 915                         idx = find_cable_index_by_id(extd, id);
 916                         if (idx >= 0)
 917                                 break;
 918                 }
 919                 mutex_unlock(&extcon_dev_list_lock);
 920
 921                 if (idx >= 0) {
 922                         edev = extd;
 923                         return extcon_register_notifier(extd, id, nb);
 924                 } else {
 925                         ret = -ENODEV;
 926                 }
 927         }
 928
 929         return ret;
 930 }
 931 EXPORT_SYMBOL_GPL(extcon_register_notifier);
 932
 933 /**
 934  * extcon_unregister_notifier() - Unregister a notifiee from the extcon device.
 935  * @edev:       the extcon device that has the external connecotr.
 936  * @id:         the unique id of each external connector in extcon enumeration.
 937  * @nb:         a notifier block to be registered.
 938  */
 939 int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id,
 940                                 struct notifier_block *nb)
 941 {
 942         unsigned long flags;
 943         int ret, idx;
 944
 945         if (!edev || !nb)
 946                 return -EINVAL;
 947
 948         idx = find_cable_index_by_id(edev, id);
 949         if (idx < 0)
 950                 return idx;
 951
 952         spin_lock_irqsave(&edev->lock, flags);
 953         ret = raw_notifier_chain_unregister(&edev->nh[idx], nb);
 954         spin_unlock_irqrestore(&edev->lock, flags);
 955
 956         return ret;
 957 }
 958 EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
 959
 960 static struct attribute *extcon_attrs[] = {
 961         &dev_attr_state.attr,
 962         &dev_attr_name.attr,
 963         NULL,
 964 };
 965 ATTRIBUTE_GROUPS(extcon);
 966
 967 static int create_extcon_class(void)
 968 {
 969         if (!extcon_class) {
 970                 extcon_class = class_create(THIS_MODULE, "extcon");
 971                 if (IS_ERR(extcon_class))
 972                         return PTR_ERR(extcon_class);
 973                 extcon_class->dev_groups = extcon_groups;
 974
 975 #if defined(CONFIG_ANDROID)
 976                 switch_class = class_compat_register("switch");
 977                 if (WARN(!switch_class, "cannot allocate"))
 978                         return -ENOMEM;
 979 #endif /* CONFIG_ANDROID */
 980         }
 981
 982         return 0;
 983 }
 984
 985 static void extcon_dev_release(struct device *dev)
 986 {
 987 }
 988
 989 static const char *muex_name = "mutually_exclusive";
 990 static void dummy_sysfs_dev_release(struct device *dev)
 991 {
 992 }
 993
 994 /*
 995  * extcon_dev_allocate() - Allocate the memory of extcon device.
 996  * @supported_cable:    Array of supported extcon ending with EXTCON_NONE.
 997  *                      If supported_cable is NULL, cable name related APIs
 998  *                      are disabled.
 999  *
1000  * This function allocates the memory for extcon device without allocating
1001  * memory in each extcon provider driver and initialize default setting for
1002  * extcon device.
1003  *
1004  * Return the pointer of extcon device if success or ERR_PTR(err) if fail
1005  */
1006 struct extcon_dev *extcon_dev_allocate(const unsigned int *supported_cable)
1007 {
1008         struct extcon_dev *edev;
1009
1010         if (!supported_cable)
1011                 return ERR_PTR(-EINVAL);
1012
1013         edev = kzalloc(sizeof(*edev), GFP_KERNEL);
1014         if (!edev)
1015                 return ERR_PTR(-ENOMEM);
1016
1017         edev->max_supported = 0;
1018         edev->supported_cable = supported_cable;
1019
1020         return edev;
1021 }
1022
1023 /*
1024  * extcon_dev_free() - Free the memory of extcon device.
1025  * @edev:       the extcon device to free
1026  */
1027 void extcon_dev_free(struct extcon_dev *edev)
1028 {
1029         kfree(edev);
1030 }
1031 EXPORT_SYMBOL_GPL(extcon_dev_free);
1032
1033 /**
1034  * extcon_dev_register() - Register a new extcon device
1035  * @edev        : the new extcon device (should be allocated before calling)
1036  *
1037  * Among the members of edev struct, please set the "user initializing data"
1038  * in any case and set the "optional callbacks" if required. However, please
1039  * do not set the values of "internal data", which are initialized by
1040  * this function.
1041  */
1042 int extcon_dev_register(struct extcon_dev *edev)
1043 {
1044         int ret, index = 0;
1045         static atomic_t edev_no = ATOMIC_INIT(-1);
1046
1047         if (!extcon_class) {
1048                 ret = create_extcon_class();
1049                 if (ret < 0)
1050                         return ret;
1051         }
1052
1053         if (!edev || !edev->supported_cable)
1054                 return -EINVAL;
1055
1056         for (; edev->supported_cable[index] != EXTCON_NONE; index++);
1057
1058         edev->max_supported = index;
1059         if (index > SUPPORTED_CABLE_MAX) {
1060                 dev_err(&edev->dev,
1061                         "exceed the maximum number of supported cables\n");
1062                 return -EINVAL;
1063         }
1064
1065         edev->dev.class = extcon_class;
1066         edev->dev.release = extcon_dev_release;
1067
1068         edev->name = dev_name(edev->dev.parent);
1069         if (IS_ERR_OR_NULL(edev->name)) {
1070                 dev_err(&edev->dev,
1071                         "extcon device name is null\n");
1072                 return -EINVAL;
1073         }
1074         dev_set_name(&edev->dev, "extcon%lu",
1075                         (unsigned long)atomic_inc_return(&edev_no));
1076
1077         if (edev->max_supported) {
1078                 char buf[10];
1079                 char *str;
1080                 struct extcon_cable *cable;
1081
1082                 edev->cables = kzalloc(sizeof(struct extcon_cable) *
1083                                        edev->max_supported, GFP_KERNEL);
1084                 if (!edev->cables) {
1085                         ret = -ENOMEM;
1086                         goto err_sysfs_alloc;
1087                 }
1088                 for (index = 0; index < edev->max_supported; index++) {
1089                         cable = &edev->cables[index];
1090
1091                         snprintf(buf, 10, "cable.%d", index);
1092                         str = kzalloc(sizeof(char) * (strlen(buf) + 1),
1093                                       GFP_KERNEL);
1094                         if (!str) {
1095                                 for (index--; index >= 0; index--) {
1096                                         cable = &edev->cables[index];
1097                                         kfree(cable->attr_g.name);
1098                                 }
1099                                 ret = -ENOMEM;
1100
1101                                 goto err_alloc_cables;
1102                         }
1103                         strcpy(str, buf);
1104
1105                         cable->edev = edev;
1106                         cable->cable_index = index;
1107                         cable->attrs[0] = &cable->attr_name.attr;
1108                         cable->attrs[1] = &cable->attr_state.attr;
1109                         cable->attrs[2] = NULL;
1110                         cable->attr_g.name = str;
1111                         cable->attr_g.attrs = cable->attrs;
1112
1113                         sysfs_attr_init(&cable->attr_name.attr);
1114                         cable->attr_name.attr.name = "name";
1115                         cable->attr_name.attr.mode = 0444;
1116                         cable->attr_name.show = cable_name_show;
1117
1118                         sysfs_attr_init(&cable->attr_state.attr);
1119                         cable->attr_state.attr.name = "state";
1120                         cable->attr_state.attr.mode = 0444;
1121                         cable->attr_state.show = cable_state_show;
1122                 }
1123         }
1124
1125         if (edev->max_supported && edev->mutually_exclusive) {
1126                 char buf[80];
1127                 char *name;
1128
1129                 /* Count the size of mutually_exclusive array */
1130                 for (index = 0; edev->mutually_exclusive[index]; index++)
1131                         ;
1132
1133                 edev->attrs_muex = kzalloc(sizeof(struct attribute *) *
1134                                            (index + 1), GFP_KERNEL);
1135                 if (!edev->attrs_muex) {
1136                         ret = -ENOMEM;
1137                         goto err_muex;
1138                 }
1139
1140                 edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) *
1141                                              index, GFP_KERNEL);
1142                 if (!edev->d_attrs_muex) {
1143                         ret = -ENOMEM;
1144                         kfree(edev->attrs_muex);
1145                         goto err_muex;
1146                 }
1147
1148                 for (index = 0; edev->mutually_exclusive[index]; index++) {
1149                         sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
1150                         name = kzalloc(sizeof(char) * (strlen(buf) + 1),
1151                                        GFP_KERNEL);
1152                         if (!name) {
1153                                 for (index--; index >= 0; index--) {
1154                                         kfree(edev->d_attrs_muex[index].attr.
1155                                               name);
1156                                 }
1157                                 kfree(edev->d_attrs_muex);
1158                                 kfree(edev->attrs_muex);
1159                                 ret = -ENOMEM;
1160                                 goto err_muex;
1161                         }
1162                         strcpy(name, buf);
1163                         sysfs_attr_init(&edev->d_attrs_muex[index].attr);
1164                         edev->d_attrs_muex[index].attr.name = name;
1165                         edev->d_attrs_muex[index].attr.mode = 0000;
1166                         edev->attrs_muex[index] = &edev->d_attrs_muex[index]
1167                                                         .attr;
1168                 }
1169                 edev->attr_g_muex.name = muex_name;
1170                 edev->attr_g_muex.attrs = edev->attrs_muex;
1171
1172         }
1173
1174         if (edev->max_supported) {
1175                 edev->extcon_dev_type.groups =
1176                         kzalloc(sizeof(struct attribute_group *) *
1177                                 (edev->max_supported + 2), GFP_KERNEL);
1178                 if (!edev->extcon_dev_type.groups) {
1179                         ret = -ENOMEM;
1180                         goto err_alloc_groups;
1181                 }
1182
1183                 edev->extcon_dev_type.name = dev_name(&edev->dev);
1184                 edev->extcon_dev_type.release = dummy_sysfs_dev_release;
1185
1186                 for (index = 0; index < edev->max_supported; index++)
1187                         edev->extcon_dev_type.groups[index] =
1188                                 &edev->cables[index].attr_g;
1189                 if (edev->mutually_exclusive)
1190                         edev->extcon_dev_type.groups[index] =
1191                                 &edev->attr_g_muex;
1192
1193                 edev->dev.type = &edev->extcon_dev_type;
1194         }
1195
1196         ret = device_register(&edev->dev);
1197         if (ret) {
1198                 put_device(&edev->dev);
1199                 goto err_dev;
1200         }
1201 #if defined(CONFIG_ANDROID)
1202         if (switch_class)
1203                 ret = class_compat_create_link(switch_class, &edev->dev, NULL);
1204 #endif /* CONFIG_ANDROID */
1205
1206         spin_lock_init(&edev->lock);
1207
1208         edev->nh = devm_kzalloc(&edev->dev,
1209                         sizeof(*edev->nh) * edev->max_supported, GFP_KERNEL);
1210         if (!edev->nh) {
1211                 ret = -ENOMEM;
1212                 goto err_dev;
1213         }
1214
1215         for (index = 0; index < edev->max_supported; index++)
1216                 RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]);
1217
1218         dev_set_drvdata(&edev->dev, edev);
1219         edev->state = 0;
1220
1221         mutex_lock(&extcon_dev_list_lock);
1222         list_add(&edev->entry, &extcon_dev_list);
1223         mutex_unlock(&extcon_dev_list_lock);
1224
1225         return 0;
1226
1227 err_dev:
1228         if (edev->max_supported)
1229                 kfree(edev->extcon_dev_type.groups);
1230 err_alloc_groups:
1231         if (edev->max_supported && edev->mutually_exclusive) {
1232                 for (index = 0; edev->mutually_exclusive[index]; index++)
1233                         kfree(edev->d_attrs_muex[index].attr.name);
1234                 kfree(edev->d_attrs_muex);
1235                 kfree(edev->attrs_muex);
1236         }
1237 err_muex:
1238         for (index = 0; index < edev->max_supported; index++)
1239                 kfree(edev->cables[index].attr_g.name);
1240 err_alloc_cables:
1241         if (edev->max_supported)
1242                 kfree(edev->cables);
1243 err_sysfs_alloc:
1244         return ret;
1245 }
1246 EXPORT_SYMBOL_GPL(extcon_dev_register);
1247
1248 /**
1249  * extcon_dev_unregister() - Unregister the extcon device.
1250  * @edev:       the extcon device instance to be unregistered.
1251  *
1252  * Note that this does not call kfree(edev) because edev was not allocated
1253  * by this class.
1254  */
1255 void extcon_dev_unregister(struct extcon_dev *edev)
1256 {
1257         int index;
1258
1259         if (!edev)
1260                 return;
1261
1262         mutex_lock(&extcon_dev_list_lock);
1263         list_del(&edev->entry);
1264         mutex_unlock(&extcon_dev_list_lock);
1265
1266         if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
1267                 dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
1268                                 dev_name(&edev->dev));
1269                 return;
1270         }
1271
1272         device_unregister(&edev->dev);
1273
1274         if (edev->mutually_exclusive && edev->max_supported) {
1275                 for (index = 0; edev->mutually_exclusive[index];
1276                                 index++)
1277                         kfree(edev->d_attrs_muex[index].attr.name);
1278                 kfree(edev->d_attrs_muex);
1279                 kfree(edev->attrs_muex);
1280         }
1281
1282         for (index = 0; index < edev->max_supported; index++)
1283                 kfree(edev->cables[index].attr_g.name);
1284
1285         if (edev->max_supported) {
1286                 kfree(edev->extcon_dev_type.groups);
1287                 kfree(edev->cables);
1288         }
1289
1290 #if defined(CONFIG_ANDROID)
1291         if (switch_class)
1292                 class_compat_remove_link(switch_class, &edev->dev, NULL);
1293 #endif
1294         put_device(&edev->dev);
1295 }
1296 EXPORT_SYMBOL_GPL(extcon_dev_unregister);
1297
1298 #ifdef CONFIG_OF
1299 /*
1300  * extcon_get_edev_by_phandle - Get the extcon device from devicetree
1301  * @dev - instance to the given device
1302  * @index - index into list of extcon_dev
1303  *
1304  * return the instance of extcon device
1305  */
1306 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1307 {
1308         struct device_node *node;
1309         struct extcon_dev *edev;
1310
1311         if (!dev)
1312                 return ERR_PTR(-EINVAL);
1313
1314         if (!dev->of_node) {
1315                 dev_dbg(dev, "device does not have a device node entry\n");
1316                 return ERR_PTR(-EINVAL);
1317         }
1318
1319         node = of_parse_phandle(dev->of_node, "extcon", index);
1320         if (!node) {
1321                 dev_dbg(dev, "failed to get phandle in %s node\n",
1322                         dev->of_node->full_name);
1323                 return ERR_PTR(-ENODEV);
1324         }
1325
1326         mutex_lock(&extcon_dev_list_lock);
1327         list_for_each_entry(edev, &extcon_dev_list, entry) {
1328                 if (edev->dev.parent && edev->dev.parent->of_node == node) {
1329                         mutex_unlock(&extcon_dev_list_lock);
1330                         of_node_put(node);
1331                         return edev;
1332                 }
1333         }
1334         mutex_unlock(&extcon_dev_list_lock);
1335         of_node_put(node);
1336
1337         return ERR_PTR(-EPROBE_DEFER);
1338 }
1339 #else
1340 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1341 {
1342         return ERR_PTR(-ENOSYS);
1343 }
1344 #endif /* CONFIG_OF */
1345 EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
1346
1347 /**
1348  * extcon_get_edev_name() - Get the name of the extcon device.
1349  * @edev:       the extcon device
1350  */
1351 const char *extcon_get_edev_name(struct extcon_dev *edev)
1352 {
1353         return !edev ? NULL : edev->name;
1354 }
1355
1356 static int __init extcon_class_init(void)
1357 {
1358         return create_extcon_class();
1359 }
1360 module_init(extcon_class_init);
1361
1362 static void __exit extcon_class_exit(void)
1363 {
1364 #if defined(CONFIG_ANDROID)
1365         class_compat_unregister(switch_class);
1366 #endif
1367         class_destroy(extcon_class);
1368 }
1369 module_exit(extcon_class_exit);
1370
1371 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
1372 MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
1373 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
1374 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1375 MODULE_DESCRIPTION("External connector (extcon) class driver");
1376 MODULE_LICENSE("GPL");