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         [EXTCON_DISP_HMD] = {
 166                 .type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
 167                 .id = EXTCON_DISP_HMD,
 168                 .name = "HMD",
 169         },
 170
 171         /* Miscellaneous external connector */
 172         [EXTCON_DOCK] = {
 173                 .type = EXTCON_TYPE_MISC,
 174                 .id = EXTCON_DOCK,
 175                 .name = "DOCK",
 176         },
 177         [EXTCON_JIG] = {
 178                 .type = EXTCON_TYPE_MISC,
 179                 .id = EXTCON_JIG,
 180                 .name = "JIG",
 181         },
 182         [EXTCON_MECHANICAL] = {
 183                 .type = EXTCON_TYPE_MISC,
 184                 .id = EXTCON_MECHANICAL,
 185                 .name = "MECHANICAL",
 186         },
 187
 188         { /* sentinel */ }
 189 };
 190
 191 /**
 192  * struct extcon_cable - An internal data for each cable of extcon device.
 193  * @edev:               The extcon device
 194  * @cable_index:        Index of this cable in the edev
 195  * @attr_g:             Attribute group for the cable
 196  * @attr_name:          "name" sysfs entry
 197  * @attr_state:         "state" sysfs entry
 198  * @attrs:              Array pointing to attr_name and attr_state for attr_g
 199  */
 200 struct extcon_cable {
 201         struct extcon_dev *edev;
 202         int cable_index;
 203
 204         struct attribute_group attr_g;
 205         struct device_attribute attr_name;
 206         struct device_attribute attr_state;
 207
 208         struct attribute *attrs[3]; /* to be fed to attr_g.attrs */
 209
 210         union extcon_property_value usb_propval[EXTCON_PROP_USB_CNT];
 211         union extcon_property_value chg_propval[EXTCON_PROP_CHG_CNT];
 212         union extcon_property_value jack_propval[EXTCON_PROP_JACK_CNT];
 213         union extcon_property_value disp_propval[EXTCON_PROP_DISP_CNT];
 214
 215         unsigned long usb_bits[BITS_TO_LONGS(EXTCON_PROP_USB_CNT)];
 216         unsigned long chg_bits[BITS_TO_LONGS(EXTCON_PROP_CHG_CNT)];
 217         unsigned long jack_bits[BITS_TO_LONGS(EXTCON_PROP_JACK_CNT)];
 218         unsigned long disp_bits[BITS_TO_LONGS(EXTCON_PROP_DISP_CNT)];
 219 };
 220
 221 static struct class *extcon_class;
 222 #if defined(CONFIG_ANDROID)
 223 static struct class_compat *switch_class;
 224 #endif /* CONFIG_ANDROID */
 225
 226 static LIST_HEAD(extcon_dev_list);
 227 static DEFINE_MUTEX(extcon_dev_list_lock);
 228
 229 /**
 230  * check_mutually_exclusive - Check if new_state violates mutually_exclusive
 231  *                            condition.
 232  * @edev:       the extcon device
 233  * @new_state:  new cable attach status for @edev
 234  *
 235  * Returns 0 if nothing violates. Returns the index + 1 for the first
 236  * violated condition.
 237  */
 238 static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
 239 {
 240         int i = 0;
 241
 242         if (!edev->mutually_exclusive)
 243                 return 0;
 244
 245         for (i = 0; edev->mutually_exclusive[i]; i++) {
 246                 int weight;
 247                 u32 correspondants = new_state & edev->mutually_exclusive[i];
 248
 249                 /* calculate the total number of bits set */
 250                 weight = hweight32(correspondants);
 251                 if (weight > 1)
 252                         return i + 1;
 253         }
 254
 255         return 0;
 256 }
 257
 258 static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id)
 259 {
 260         int i;
 261
 262         /* Find the the index of extcon cable in edev->supported_cable */
 263         for (i = 0; i < edev->max_supported; i++) {
 264                 if (edev->supported_cable[i] == id)
 265                         return i;
 266         }
 267
 268         return -EINVAL;
 269 }
 270
 271 static int get_extcon_type(unsigned int prop)
 272 {
 273         switch (prop) {
 274         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 275                 return EXTCON_TYPE_USB;
 276         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 277                 return EXTCON_TYPE_CHG;
 278         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 279                 return EXTCON_TYPE_JACK;
 280         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 281                 return EXTCON_TYPE_DISP;
 282         default:
 283                 return -EINVAL;
 284         }
 285 }
 286
 287 static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index)
 288 {
 289         return !!(edev->state & BIT(index));
 290 }
 291
 292 static bool is_extcon_changed(struct extcon_dev *edev, int index,
 293                                 bool new_state)
 294 {
 295         int state = !!(edev->state & BIT(index));
 296         return (state != new_state);
 297 }
 298
 299 static bool is_extcon_property_supported(unsigned int id, unsigned int prop)
 300 {
 301         int type;
 302
 303         /* Check whether the property is supported or not. */
 304         type = get_extcon_type(prop);
 305         if (type < 0)
 306                 return false;
 307
 308         /* Check whether a specific extcon id supports the property or not. */
 309         return !!(extcon_info[id].type & type);
 310 }
 311
 312 static int is_extcon_property_capability(struct extcon_dev *edev,
 313                                 unsigned int id, int index,unsigned int prop)
 314 {
 315         struct extcon_cable *cable;
 316         int type, ret;
 317
 318         /* Check whether the property is supported or not. */
 319         type = get_extcon_type(prop);
 320         if (type < 0)
 321                 return type;
 322
 323         cable = &edev->cables[index];
 324
 325         switch (type) {
 326         case EXTCON_TYPE_USB:
 327                 ret = test_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
 328                 break;
 329         case EXTCON_TYPE_CHG:
 330                 ret = test_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
 331                 break;
 332         case EXTCON_TYPE_JACK:
 333                 ret = test_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
 334                 break;
 335         case EXTCON_TYPE_DISP:
 336                 ret = test_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
 337                 break;
 338         default:
 339                 ret = -EINVAL;
 340         }
 341
 342         return ret;
 343 }
 344
 345 static void init_property(struct extcon_dev *edev, unsigned int id, int index)
 346 {
 347         unsigned int type = extcon_info[id].type;
 348         struct extcon_cable *cable = &edev->cables[index];
 349
 350         if (EXTCON_TYPE_USB & type)
 351                 memset(cable->usb_propval, 0, sizeof(cable->usb_propval));
 352         if (EXTCON_TYPE_CHG & type)
 353                 memset(cable->chg_propval, 0, sizeof(cable->chg_propval));
 354         if (EXTCON_TYPE_JACK & type)
 355                 memset(cable->jack_propval, 0, sizeof(cable->jack_propval));
 356         if (EXTCON_TYPE_DISP & type)
 357                 memset(cable->disp_propval, 0, sizeof(cable->disp_propval));
 358 }
 359
 360 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 361                           char *buf)
 362 {
 363         int i, count = 0;
 364         struct extcon_dev *edev = dev_get_drvdata(dev);
 365
 366         if (edev->max_supported == 0)
 367                 return sprintf(buf, "%u\n", edev->state);
 368
 369         for (i = 0; i < edev->max_supported; i++) {
 370                 count += sprintf(buf + count, "%s=%d\n",
 371                                 extcon_info[edev->supported_cable[i]].name,
 372                                  !!(edev->state & (1 << i)));
 373         }
 374
 375         return count;
 376 }
 377 static DEVICE_ATTR_RO(state);
 378
 379 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 380                 char *buf)
 381 {
 382         struct extcon_dev *edev = dev_get_drvdata(dev);
 383
 384         return sprintf(buf, "%s\n", edev->name);
 385 }
 386 static DEVICE_ATTR_RO(name);
 387
 388 static ssize_t cable_name_show(struct device *dev,
 389                                struct device_attribute *attr, char *buf)
 390 {
 391         struct extcon_cable *cable = container_of(attr, struct extcon_cable,
 392                                                   attr_name);
 393         int i = cable->cable_index;
 394
 395         return sprintf(buf, "%s\n",
 396                         extcon_info[cable->edev->supported_cable[i]].name);
 397 }
 398
 399 static ssize_t cable_state_show(struct device *dev,
 400                                 struct device_attribute *attr, char *buf)
 401 {
 402         struct extcon_cable *cable = container_of(attr, struct extcon_cable,
 403                                                   attr_state);
 404
 405         int i = cable->cable_index;
 406
 407         return sprintf(buf, "%d\n",
 408                 extcon_get_state(cable->edev, cable->edev->supported_cable[i]));
 409 }
 410
 411 /**
 412  * extcon_sync()        - Synchronize the states for both the attached/detached
 413  * @edev:               the extcon device that has the cable.
 414  *
 415  * This function send a notification to synchronize the all states of a
 416  * specific external connector
 417  */
 418 int extcon_sync(struct extcon_dev *edev, unsigned int id)
 419 {
 420         char name_buf[120];
 421         char state_buf[120];
 422         char *prop_buf;
 423         char *envp[3];
 424         int env_offset = 0;
 425         int length;
 426         int index;
 427         int state;
 428         unsigned long flags;
 429
 430         if (!edev)
 431                 return -EINVAL;
 432
 433         index = find_cable_index_by_id(edev, id);
 434         if (index < 0)
 435                 return index;
 436
 437         spin_lock_irqsave(&edev->lock, flags);
 438
 439         state = !!(edev->state & BIT(index));
 440         raw_notifier_call_chain(&edev->nh[index], state, edev);
 441
 442         /* This could be in interrupt handler */
 443         prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
 444         if (!prop_buf) {
 445                 /* Unlock early before uevent */
 446                 spin_unlock_irqrestore(&edev->lock, flags);
 447
 448                 dev_err(&edev->dev, "out of memory in extcon_set_state\n");
 449                 kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE);
 450
 451                 return 0;
 452         }
 453
 454         length = name_show(&edev->dev, NULL, prop_buf);
 455         if (length > 0) {
 456                 if (prop_buf[length - 1] == '\n')
 457                         prop_buf[length - 1] = 0;
 458                 snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf);
 459                 envp[env_offset++] = name_buf;
 460         }
 461
 462         length = state_show(&edev->dev, NULL, prop_buf);
 463         if (length > 0) {
 464                 if (prop_buf[length - 1] == '\n')
 465                         prop_buf[length - 1] = 0;
 466                 snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf);
 467                 envp[env_offset++] = state_buf;
 468         }
 469         envp[env_offset] = NULL;
 470
 471         /* Unlock early before uevent */
 472         spin_unlock_irqrestore(&edev->lock, flags);
 473         kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp);
 474         free_page((unsigned long)prop_buf);
 475
 476         return 0;
 477 }
 478 EXPORT_SYMBOL_GPL(extcon_sync);
 479
 480 /**
 481  * extcon_get_state() - Get the state of a external connector.
 482  * @edev:       the extcon device that has the cable.
 483  * @id:         the unique id of each external connector in extcon enumeration.
 484  */
 485 int extcon_get_state(struct extcon_dev *edev, const unsigned int id)
 486 {
 487         int index, state;
 488         unsigned long flags;
 489
 490         if (!edev)
 491                 return -EINVAL;
 492
 493         index = find_cable_index_by_id(edev, id);
 494         if (index < 0)
 495                 return index;
 496
 497         spin_lock_irqsave(&edev->lock, flags);
 498         state = is_extcon_attached(edev, index);
 499         spin_unlock_irqrestore(&edev->lock, flags);
 500
 501         return state;
 502 }
 503 EXPORT_SYMBOL_GPL(extcon_get_state);
 504
 505 /**
 506  * extcon_set_state() - Set the state of a external connector.
 507  *                      without a notification.
 508  * @edev:               the extcon device that has the cable.
 509  * @id:                 the unique id of each external connector
 510  *                      in extcon enumeration.
 511  * @state:              the new cable status. The default semantics is
 512  *                      true: attached / false: detached.
 513  *
 514  * This function only set the state of a external connector without
 515  * a notification. To synchronize the data of a external connector,
 516  * use extcon_set_state_sync() and extcon_sync().
 517  */
 518 int extcon_set_state(struct extcon_dev *edev, unsigned int id,
 519                                 bool cable_state)
 520 {
 521         unsigned long flags;
 522         int index, ret = 0;
 523
 524         if (!edev)
 525                 return -EINVAL;
 526
 527         index = find_cable_index_by_id(edev, id);
 528         if (index < 0)
 529                 return index;
 530
 531         spin_lock_irqsave(&edev->lock, flags);
 532
 533         /* Check whether the external connector's state is changed. */
 534         if (!is_extcon_changed(edev, index, cable_state))
 535                 goto out;
 536
 537         if (check_mutually_exclusive(edev,
 538                 (edev->state & ~BIT(index)) | (cable_state & BIT(index)))) {
 539                 ret = -EPERM;
 540                 goto out;
 541         }
 542
 543         /*
 544          * Initialize the value of extcon property before setting
 545          * the detached state for an external connector.
 546          */
 547         if (!cable_state)
 548                 init_property(edev, id, index);
 549
 550         /* Update the state for a external connector. */
 551         if (cable_state)
 552                 edev->state |= BIT(index);
 553         else
 554                 edev->state &= ~(BIT(index));
 555 out:
 556         spin_unlock_irqrestore(&edev->lock, flags);
 557
 558         return ret;
 559 }
 560 EXPORT_SYMBOL_GPL(extcon_set_state);
 561
 562 /**
 563  * extcon_set_state_sync() - Set the state of a external connector
 564  *                      with a notification.
 565  * @edev:               the extcon device that has the cable.
 566  * @id:                 the unique id of each external connector
 567  *                      in extcon enumeration.
 568  * @state:              the new cable status. The default semantics is
 569  *                      true: attached / false: detached.
 570  *
 571  * This function set the state of external connector and synchronize the data
 572  * by usning a notification.
 573  */
 574 int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id,
 575                                 bool cable_state)
 576 {
 577         int ret, index;
 578         unsigned long flags;
 579
 580         index = find_cable_index_by_id(edev, id);
 581         if (index < 0)
 582                 return index;
 583
 584         /* Check whether the external connector's state is changed. */
 585         spin_lock_irqsave(&edev->lock, flags);
 586         ret = is_extcon_changed(edev, index, cable_state);
 587         spin_unlock_irqrestore(&edev->lock, flags);
 588         if (!ret)
 589                 return 0;
 590
 591         ret = extcon_set_state(edev, id, cable_state);
 592         if (ret < 0)
 593                 return ret;
 594
 595         return extcon_sync(edev, id);
 596 }
 597 EXPORT_SYMBOL_GPL(extcon_set_state_sync);
 598
 599 /**
 600  * extcon_get_property() - Get the property value of a specific cable.
 601  * @edev:               the extcon device that has the cable.
 602  * @id:                 the unique id of each external connector
 603  *                      in extcon enumeration.
 604  * @prop:               the property id among enum extcon_property.
 605  * @prop_val:           the pointer which store the value of property.
 606  *
 607  * When getting the property value of external connector, the external connector
 608  * should be attached. If detached state, function just return 0 without
 609  * property value. Also, the each property should be included in the list of
 610  * supported properties according to the type of external connectors.
 611  *
 612  * Returns 0 if success or error number if fail
 613  */
 614 int extcon_get_property(struct extcon_dev *edev, unsigned int id,
 615                                 unsigned int prop,
 616                                 union extcon_property_value *prop_val)
 617 {
 618         struct extcon_cable *cable;
 619         unsigned long flags;
 620         int index, ret = 0;
 621
 622         *prop_val = (union extcon_property_value)(0);
 623
 624         if (!edev)
 625                 return -EINVAL;
 626
 627         /* Check whether the property is supported or not */
 628         if (!is_extcon_property_supported(id, prop))
 629                 return -EINVAL;
 630
 631         /* Find the cable index of external connector by using id */
 632         index = find_cable_index_by_id(edev, id);
 633         if (index < 0)
 634                 return index;
 635
 636         spin_lock_irqsave(&edev->lock, flags);
 637
 638         /* Check whether the property is available or not. */
 639         if (!is_extcon_property_capability(edev, id, index, prop)) {
 640                 spin_unlock_irqrestore(&edev->lock, flags);
 641                 return -EPERM;
 642         }
 643
 644         /*
 645          * Check whether the external connector is attached.
 646          * If external connector is detached, the user can not
 647          * get the property value.
 648          */
 649         if (!is_extcon_attached(edev, index)) {
 650                 spin_unlock_irqrestore(&edev->lock, flags);
 651                 return 0;
 652         }
 653
 654         cable = &edev->cables[index];
 655
 656         /* Get the property value according to extcon type */
 657         switch (prop) {
 658         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 659                 *prop_val = cable->usb_propval[prop - EXTCON_PROP_USB_MIN];
 660                 break;
 661         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 662                 *prop_val = cable->chg_propval[prop - EXTCON_PROP_CHG_MIN];
 663                 break;
 664         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 665                 *prop_val = cable->jack_propval[prop - EXTCON_PROP_JACK_MIN];
 666                 break;
 667         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 668                 *prop_val = cable->disp_propval[prop - EXTCON_PROP_DISP_MIN];
 669                 break;
 670         default:
 671                 ret = -EINVAL;
 672                 break;
 673         }
 674
 675         spin_unlock_irqrestore(&edev->lock, flags);
 676
 677         return ret;
 678 }
 679 EXPORT_SYMBOL_GPL(extcon_get_property);
 680
 681 /**
 682  * extcon_set_property() - Set the property value of a specific cable.
 683  * @edev:               the extcon device that has the cable.
 684  * @id:                 the unique id of each external connector
 685  *                      in extcon enumeration.
 686  * @prop:               the property id among enum extcon_property.
 687  * @prop_val:           the pointer including the new value of property.
 688  *
 689  * The each property should be included in the list of supported properties
 690  * according to the type of external connectors.
 691  *
 692  * Returns 0 if success or error number if fail
 693  */
 694 int extcon_set_property(struct extcon_dev *edev, unsigned int id,
 695                                 unsigned int prop,
 696                                 union extcon_property_value prop_val)
 697 {
 698         struct extcon_cable *cable;
 699         unsigned long flags;
 700         int index, ret = 0;
 701
 702         if (!edev)
 703                 return -EINVAL;
 704
 705         /* Check whether the property is supported or not */
 706         if (!is_extcon_property_supported(id, prop))
 707                 return -EINVAL;
 708
 709         /* Find the cable index of external connector by using id */
 710         index = find_cable_index_by_id(edev, id);
 711         if (index < 0)
 712                 return index;
 713
 714         spin_lock_irqsave(&edev->lock, flags);
 715
 716         /* Check whether the property is available or not. */
 717         if (!is_extcon_property_capability(edev, id, index, prop)) {
 718                 spin_unlock_irqrestore(&edev->lock, flags);
 719                 return -EPERM;
 720         }
 721
 722         cable = &edev->cables[index];
 723
 724         /* Set the property value according to extcon type */
 725         switch (prop) {
 726         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 727                 cable->usb_propval[prop - EXTCON_PROP_USB_MIN] = prop_val;
 728                 break;
 729         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 730                 cable->chg_propval[prop - EXTCON_PROP_CHG_MIN] = prop_val;
 731                 break;
 732         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 733                 cable->jack_propval[prop - EXTCON_PROP_JACK_MIN] = prop_val;
 734                 break;
 735         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 736                 cable->disp_propval[prop - EXTCON_PROP_DISP_MIN] = prop_val;
 737                 break;
 738         default:
 739                 ret = -EINVAL;
 740                 break;
 741         }
 742
 743         spin_unlock_irqrestore(&edev->lock, flags);
 744
 745         return ret;
 746 }
 747 EXPORT_SYMBOL_GPL(extcon_set_property);
 748
 749 /**
 750  * extcon_set_property_sync() - Set the property value of a specific cable
 751                         with a notification.
 752  * @prop_val:           the pointer including the new value of property.
 753  *
 754  * When setting the property value of external connector, the external connector
 755  * should be attached. The each property should be included in the list of
 756  * supported properties according to the type of external connectors.
 757  *
 758  * Returns 0 if success or error number if fail
 759  */
 760 int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id,
 761                                 unsigned int prop,
 762                                 union extcon_property_value prop_val)
 763 {
 764         int ret;
 765
 766         ret = extcon_set_property(edev, id, prop, prop_val);
 767         if (ret < 0)
 768                 return ret;
 769
 770         return extcon_sync(edev, id);
 771 }
 772 EXPORT_SYMBOL_GPL(extcon_set_property_sync);
 773
 774 /**
 775  * extcon_get_property_capability() - Get the capability of property
 776  *                      of an external connector.
 777  * @edev:               the extcon device that has the cable.
 778  * @id:                 the unique id of each external connector
 779  *                      in extcon enumeration.
 780  * @prop:               the property id among enum extcon_property.
 781  *
 782  * Returns 1 if the property is available or 0 if not available.
 783  */
 784 int extcon_get_property_capability(struct extcon_dev *edev, unsigned int id,
 785                                         unsigned int prop)
 786 {
 787         int index;
 788
 789         if (!edev)
 790                 return -EINVAL;
 791
 792         /* Check whether the property is supported or not */
 793         if (!is_extcon_property_supported(id, prop))
 794                 return -EINVAL;
 795
 796         /* Find the cable index of external connector by using id */
 797         index = find_cable_index_by_id(edev, id);
 798         if (index < 0)
 799                 return index;
 800
 801         return is_extcon_property_capability(edev, id, index, prop);
 802 }
 803 EXPORT_SYMBOL_GPL(extcon_get_property_capability);
 804
 805 /**
 806  * extcon_set_property_capability() - Set the capability of a property
 807  *                      of an external connector.
 808  * @edev:               the extcon device that has the cable.
 809  * @id:                 the unique id of each external connector
 810  *                      in extcon enumeration.
 811  * @prop:               the property id among enum extcon_property.
 812  *
 813  * This function set the capability of a property for an external connector
 814  * to mark the bit in capability bitmap which mean the available state of
 815  * a property.
 816  *
 817  * Returns 0 if success or error number if fail
 818  */
 819 int extcon_set_property_capability(struct extcon_dev *edev, unsigned int id,
 820                                         unsigned int prop)
 821 {
 822         struct extcon_cable *cable;
 823         int index, type, ret = 0;
 824
 825         if (!edev)
 826                 return -EINVAL;
 827
 828         /* Check whether the property is supported or not. */
 829         if (!is_extcon_property_supported(id, prop))
 830                 return -EINVAL;
 831
 832         /* Find the cable index of external connector by using id. */
 833         index = find_cable_index_by_id(edev, id);
 834         if (index < 0)
 835                 return index;
 836
 837         type = get_extcon_type(prop);
 838         if (type < 0)
 839                 return type;
 840
 841         cable = &edev->cables[index];
 842
 843         switch (type) {
 844         case EXTCON_TYPE_USB:
 845                 __set_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
 846                 break;
 847         case EXTCON_TYPE_CHG:
 848                 __set_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
 849                 break;
 850         case EXTCON_TYPE_JACK:
 851                 __set_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
 852                 break;
 853         case EXTCON_TYPE_DISP:
 854                 __set_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
 855                 break;
 856         default:
 857                 ret = -EINVAL;
 858         }
 859
 860         return ret;
 861 }
 862 EXPORT_SYMBOL_GPL(extcon_set_property_capability);
 863
 864 /**
 865  * extcon_get_extcon_dev() - Get the extcon device instance from the name
 866  * @extcon_name:        The extcon name provided with extcon_dev_register()
 867  */
 868 struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
 869 {
 870         struct extcon_dev *sd;
 871
 872         if (!extcon_name)
 873                 return ERR_PTR(-EINVAL);
 874
 875         mutex_lock(&extcon_dev_list_lock);
 876         list_for_each_entry(sd, &extcon_dev_list, entry) {
 877                 if (!strcmp(sd->name, extcon_name))
 878                         goto out;
 879         }
 880         sd = NULL;
 881 out:
 882         mutex_unlock(&extcon_dev_list_lock);
 883         return sd;
 884 }
 885 EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
 886
 887 /**
 888  * extcon_register_notifier() - Register a notifiee to get notified by
 889  *                              any attach status changes from the extcon.
 890  * @edev:       the extcon device that has the external connecotr.
 891  * @id:         the unique id of each external connector in extcon enumeration.
 892  * @nb:         a notifier block to be registered.
 893  *
 894  * Note that the second parameter given to the callback of nb (val) is
 895  * "old_state", not the current state. The current state can be retrieved
 896  * by looking at the third pameter (edev pointer)'s state value.
 897  */
 898 int extcon_register_notifier(struct extcon_dev *edev, unsigned int id,
 899                              struct notifier_block *nb)
 900 {
 901         unsigned long flags;
 902         int ret, idx = -EINVAL;
 903
 904         if (!nb)
 905                 return -EINVAL;
 906
 907         if (edev) {
 908                 idx = find_cable_index_by_id(edev, id);
 909                 if (idx < 0)
 910                         return idx;
 911
 912                 spin_lock_irqsave(&edev->lock, flags);
 913                 ret = raw_notifier_chain_register(&edev->nh[idx], nb);
 914                 spin_unlock_irqrestore(&edev->lock, flags);
 915         } else {
 916                 struct extcon_dev *extd;
 917
 918                 mutex_lock(&extcon_dev_list_lock);
 919                 list_for_each_entry(extd, &extcon_dev_list, entry) {
 920                         idx = find_cable_index_by_id(extd, id);
 921                         if (idx >= 0)
 922                                 break;
 923                 }
 924                 mutex_unlock(&extcon_dev_list_lock);
 925
 926                 if (idx >= 0) {
 927                         edev = extd;
 928                         return extcon_register_notifier(extd, id, nb);
 929                 } else {
 930                         ret = -ENODEV;
 931                 }
 932         }
 933
 934         return ret;
 935 }
 936 EXPORT_SYMBOL_GPL(extcon_register_notifier);
 937
 938 /**
 939  * extcon_unregister_notifier() - Unregister a notifiee from the extcon device.
 940  * @edev:       the extcon device that has the external connecotr.
 941  * @id:         the unique id of each external connector in extcon enumeration.
 942  * @nb:         a notifier block to be registered.
 943  */
 944 int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id,
 945                                 struct notifier_block *nb)
 946 {
 947         unsigned long flags;
 948         int ret, idx;
 949
 950         if (!edev || !nb)
 951                 return -EINVAL;
 952
 953         idx = find_cable_index_by_id(edev, id);
 954         if (idx < 0)
 955                 return idx;
 956
 957         spin_lock_irqsave(&edev->lock, flags);
 958         ret = raw_notifier_chain_unregister(&edev->nh[idx], nb);
 959         spin_unlock_irqrestore(&edev->lock, flags);
 960
 961         return ret;
 962 }
 963 EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
 964
 965 static struct attribute *extcon_attrs[] = {
 966         &dev_attr_state.attr,
 967         &dev_attr_name.attr,
 968         NULL,
 969 };
 970 ATTRIBUTE_GROUPS(extcon);
 971
 972 static int create_extcon_class(void)
 973 {
 974         if (!extcon_class) {
 975                 extcon_class = class_create(THIS_MODULE, "extcon");
 976                 if (IS_ERR(extcon_class))
 977                         return PTR_ERR(extcon_class);
 978                 extcon_class->dev_groups = extcon_groups;
 979
 980 #if defined(CONFIG_ANDROID)
 981                 switch_class = class_compat_register("switch");
 982                 if (WARN(!switch_class, "cannot allocate"))
 983                         return -ENOMEM;
 984 #endif /* CONFIG_ANDROID */
 985         }
 986
 987         return 0;
 988 }
 989
 990 static void extcon_dev_release(struct device *dev)
 991 {
 992 }
 993
 994 static const char *muex_name = "mutually_exclusive";
 995 static void dummy_sysfs_dev_release(struct device *dev)
 996 {
 997 }
 998
 999 /*
1000  * extcon_dev_allocate() - Allocate the memory of extcon device.
1001  * @supported_cable:    Array of supported extcon ending with EXTCON_NONE.
1002  *                      If supported_cable is NULL, cable name related APIs
1003  *                      are disabled.
1004  *
1005  * This function allocates the memory for extcon device without allocating
1006  * memory in each extcon provider driver and initialize default setting for
1007  * extcon device.
1008  *
1009  * Return the pointer of extcon device if success or ERR_PTR(err) if fail
1010  */
1011 struct extcon_dev *extcon_dev_allocate(const unsigned int *supported_cable)
1012 {
1013         struct extcon_dev *edev;
1014
1015         if (!supported_cable)
1016                 return ERR_PTR(-EINVAL);
1017
1018         edev = kzalloc(sizeof(*edev), GFP_KERNEL);
1019         if (!edev)
1020                 return ERR_PTR(-ENOMEM);
1021
1022         edev->max_supported = 0;
1023         edev->supported_cable = supported_cable;
1024
1025         return edev;
1026 }
1027
1028 /*
1029  * extcon_dev_free() - Free the memory of extcon device.
1030  * @edev:       the extcon device to free
1031  */
1032 void extcon_dev_free(struct extcon_dev *edev)
1033 {
1034         kfree(edev);
1035 }
1036 EXPORT_SYMBOL_GPL(extcon_dev_free);
1037
1038 /**
1039  * extcon_dev_register() - Register a new extcon device
1040  * @edev        : the new extcon device (should be allocated before calling)
1041  *
1042  * Among the members of edev struct, please set the "user initializing data"
1043  * in any case and set the "optional callbacks" if required. However, please
1044  * do not set the values of "internal data", which are initialized by
1045  * this function.
1046  */
1047 int extcon_dev_register(struct extcon_dev *edev)
1048 {
1049         int ret, index = 0;
1050         static atomic_t edev_no = ATOMIC_INIT(-1);
1051
1052         if (!extcon_class) {
1053                 ret = create_extcon_class();
1054                 if (ret < 0)
1055                         return ret;
1056         }
1057
1058         if (!edev || !edev->supported_cable)
1059                 return -EINVAL;
1060
1061         for (; edev->supported_cable[index] != EXTCON_NONE; index++);
1062
1063         edev->max_supported = index;
1064         if (index > SUPPORTED_CABLE_MAX) {
1065                 dev_err(&edev->dev,
1066                         "exceed the maximum number of supported cables\n");
1067                 return -EINVAL;
1068         }
1069
1070         edev->dev.class = extcon_class;
1071         edev->dev.release = extcon_dev_release;
1072
1073         edev->name = dev_name(edev->dev.parent);
1074         if (IS_ERR_OR_NULL(edev->name)) {
1075                 dev_err(&edev->dev,
1076                         "extcon device name is null\n");
1077                 return -EINVAL;
1078         }
1079         dev_set_name(&edev->dev, "extcon%lu",
1080                         (unsigned long)atomic_inc_return(&edev_no));
1081
1082         if (edev->max_supported) {
1083                 char buf[10];
1084                 char *str;
1085                 struct extcon_cable *cable;
1086
1087                 edev->cables = kzalloc(sizeof(struct extcon_cable) *
1088                                        edev->max_supported, GFP_KERNEL);
1089                 if (!edev->cables) {
1090                         ret = -ENOMEM;
1091                         goto err_sysfs_alloc;
1092                 }
1093                 for (index = 0; index < edev->max_supported; index++) {
1094                         cable = &edev->cables[index];
1095
1096                         snprintf(buf, 10, "cable.%d", index);
1097                         str = kzalloc(sizeof(char) * (strlen(buf) + 1),
1098                                       GFP_KERNEL);
1099                         if (!str) {
1100                                 for (index--; index >= 0; index--) {
1101                                         cable = &edev->cables[index];
1102                                         kfree(cable->attr_g.name);
1103                                 }
1104                                 ret = -ENOMEM;
1105
1106                                 goto err_alloc_cables;
1107                         }
1108                         strcpy(str, buf);
1109
1110                         cable->edev = edev;
1111                         cable->cable_index = index;
1112                         cable->attrs[0] = &cable->attr_name.attr;
1113                         cable->attrs[1] = &cable->attr_state.attr;
1114                         cable->attrs[2] = NULL;
1115                         cable->attr_g.name = str;
1116                         cable->attr_g.attrs = cable->attrs;
1117
1118                         sysfs_attr_init(&cable->attr_name.attr);
1119                         cable->attr_name.attr.name = "name";
1120                         cable->attr_name.attr.mode = 0444;
1121                         cable->attr_name.show = cable_name_show;
1122
1123                         sysfs_attr_init(&cable->attr_state.attr);
1124                         cable->attr_state.attr.name = "state";
1125                         cable->attr_state.attr.mode = 0444;
1126                         cable->attr_state.show = cable_state_show;
1127                 }
1128         }
1129
1130         if (edev->max_supported && edev->mutually_exclusive) {
1131                 char buf[80];
1132                 char *name;
1133
1134                 /* Count the size of mutually_exclusive array */
1135                 for (index = 0; edev->mutually_exclusive[index]; index++)
1136                         ;
1137
1138                 edev->attrs_muex = kzalloc(sizeof(struct attribute *) *
1139                                            (index + 1), GFP_KERNEL);
1140                 if (!edev->attrs_muex) {
1141                         ret = -ENOMEM;
1142                         goto err_muex;
1143                 }
1144
1145                 edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) *
1146                                              index, GFP_KERNEL);
1147                 if (!edev->d_attrs_muex) {
1148                         ret = -ENOMEM;
1149                         kfree(edev->attrs_muex);
1150                         goto err_muex;
1151                 }
1152
1153                 for (index = 0; edev->mutually_exclusive[index]; index++) {
1154                         sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
1155                         name = kzalloc(sizeof(char) * (strlen(buf) + 1),
1156                                        GFP_KERNEL);
1157                         if (!name) {
1158                                 for (index--; index >= 0; index--) {
1159                                         kfree(edev->d_attrs_muex[index].attr.
1160                                               name);
1161                                 }
1162                                 kfree(edev->d_attrs_muex);
1163                                 kfree(edev->attrs_muex);
1164                                 ret = -ENOMEM;
1165                                 goto err_muex;
1166                         }
1167                         strcpy(name, buf);
1168                         sysfs_attr_init(&edev->d_attrs_muex[index].attr);
1169                         edev->d_attrs_muex[index].attr.name = name;
1170                         edev->d_attrs_muex[index].attr.mode = 0000;
1171                         edev->attrs_muex[index] = &edev->d_attrs_muex[index]
1172                                                         .attr;
1173                 }
1174                 edev->attr_g_muex.name = muex_name;
1175                 edev->attr_g_muex.attrs = edev->attrs_muex;
1176
1177         }
1178
1179         if (edev->max_supported) {
1180                 edev->extcon_dev_type.groups =
1181                         kzalloc(sizeof(struct attribute_group *) *
1182                                 (edev->max_supported + 2), GFP_KERNEL);
1183                 if (!edev->extcon_dev_type.groups) {
1184                         ret = -ENOMEM;
1185                         goto err_alloc_groups;
1186                 }
1187
1188                 edev->extcon_dev_type.name = dev_name(&edev->dev);
1189                 edev->extcon_dev_type.release = dummy_sysfs_dev_release;
1190
1191                 for (index = 0; index < edev->max_supported; index++)
1192                         edev->extcon_dev_type.groups[index] =
1193                                 &edev->cables[index].attr_g;
1194                 if (edev->mutually_exclusive)
1195                         edev->extcon_dev_type.groups[index] =
1196                                 &edev->attr_g_muex;
1197
1198                 edev->dev.type = &edev->extcon_dev_type;
1199         }
1200
1201         ret = device_register(&edev->dev);
1202         if (ret) {
1203                 put_device(&edev->dev);
1204                 goto err_dev;
1205         }
1206 #if defined(CONFIG_ANDROID)
1207         if (switch_class)
1208                 ret = class_compat_create_link(switch_class, &edev->dev, NULL);
1209 #endif /* CONFIG_ANDROID */
1210
1211         spin_lock_init(&edev->lock);
1212
1213         edev->nh = devm_kzalloc(&edev->dev,
1214                         sizeof(*edev->nh) * edev->max_supported, GFP_KERNEL);
1215         if (!edev->nh) {
1216                 ret = -ENOMEM;
1217                 goto err_dev;
1218         }
1219
1220         for (index = 0; index < edev->max_supported; index++)
1221                 RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]);
1222
1223         dev_set_drvdata(&edev->dev, edev);
1224         edev->state = 0;
1225
1226         mutex_lock(&extcon_dev_list_lock);
1227         list_add(&edev->entry, &extcon_dev_list);
1228         mutex_unlock(&extcon_dev_list_lock);
1229
1230         return 0;
1231
1232 err_dev:
1233         if (edev->max_supported)
1234                 kfree(edev->extcon_dev_type.groups);
1235 err_alloc_groups:
1236         if (edev->max_supported && edev->mutually_exclusive) {
1237                 for (index = 0; edev->mutually_exclusive[index]; index++)
1238                         kfree(edev->d_attrs_muex[index].attr.name);
1239                 kfree(edev->d_attrs_muex);
1240                 kfree(edev->attrs_muex);
1241         }
1242 err_muex:
1243         for (index = 0; index < edev->max_supported; index++)
1244                 kfree(edev->cables[index].attr_g.name);
1245 err_alloc_cables:
1246         if (edev->max_supported)
1247                 kfree(edev->cables);
1248 err_sysfs_alloc:
1249         return ret;
1250 }
1251 EXPORT_SYMBOL_GPL(extcon_dev_register);
1252
1253 /**
1254  * extcon_dev_unregister() - Unregister the extcon device.
1255  * @edev:       the extcon device instance to be unregistered.
1256  *
1257  * Note that this does not call kfree(edev) because edev was not allocated
1258  * by this class.
1259  */
1260 void extcon_dev_unregister(struct extcon_dev *edev)
1261 {
1262         int index;
1263
1264         if (!edev)
1265                 return;
1266
1267         mutex_lock(&extcon_dev_list_lock);
1268         list_del(&edev->entry);
1269         mutex_unlock(&extcon_dev_list_lock);
1270
1271         if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
1272                 dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
1273                                 dev_name(&edev->dev));
1274                 return;
1275         }
1276
1277         device_unregister(&edev->dev);
1278
1279         if (edev->mutually_exclusive && edev->max_supported) {
1280                 for (index = 0; edev->mutually_exclusive[index];
1281                                 index++)
1282                         kfree(edev->d_attrs_muex[index].attr.name);
1283                 kfree(edev->d_attrs_muex);
1284                 kfree(edev->attrs_muex);
1285         }
1286
1287         for (index = 0; index < edev->max_supported; index++)
1288                 kfree(edev->cables[index].attr_g.name);
1289
1290         if (edev->max_supported) {
1291                 kfree(edev->extcon_dev_type.groups);
1292                 kfree(edev->cables);
1293         }
1294
1295 #if defined(CONFIG_ANDROID)
1296         if (switch_class)
1297                 class_compat_remove_link(switch_class, &edev->dev, NULL);
1298 #endif
1299         put_device(&edev->dev);
1300 }
1301 EXPORT_SYMBOL_GPL(extcon_dev_unregister);
1302
1303 #ifdef CONFIG_OF
1304 /*
1305  * extcon_get_edev_by_phandle - Get the extcon device from devicetree
1306  * @dev - instance to the given device
1307  * @index - index into list of extcon_dev
1308  *
1309  * return the instance of extcon device
1310  */
1311 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1312 {
1313         struct device_node *node;
1314         struct extcon_dev *edev;
1315
1316         if (!dev)
1317                 return ERR_PTR(-EINVAL);
1318
1319         if (!dev->of_node) {
1320                 dev_dbg(dev, "device does not have a device node entry\n");
1321                 return ERR_PTR(-EINVAL);
1322         }
1323
1324         node = of_parse_phandle(dev->of_node, "extcon", index);
1325         if (!node) {
1326                 dev_dbg(dev, "failed to get phandle in %s node\n",
1327                         dev->of_node->full_name);
1328                 return ERR_PTR(-ENODEV);
1329         }
1330
1331         mutex_lock(&extcon_dev_list_lock);
1332         list_for_each_entry(edev, &extcon_dev_list, entry) {
1333                 if (edev->dev.parent && edev->dev.parent->of_node == node) {
1334                         mutex_unlock(&extcon_dev_list_lock);
1335                         of_node_put(node);
1336                         return edev;
1337                 }
1338         }
1339         mutex_unlock(&extcon_dev_list_lock);
1340         of_node_put(node);
1341
1342         return ERR_PTR(-EPROBE_DEFER);
1343 }
1344 #else
1345 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1346 {
1347         return ERR_PTR(-ENOSYS);
1348 }
1349 #endif /* CONFIG_OF */
1350 EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
1351
1352 /**
1353  * extcon_get_edev_name() - Get the name of the extcon device.
1354  * @edev:       the extcon device
1355  */
1356 const char *extcon_get_edev_name(struct extcon_dev *edev)
1357 {
1358         return !edev ? NULL : edev->name;
1359 }
1360
1361 static int __init extcon_class_init(void)
1362 {
1363         return create_extcon_class();
1364 }
1365 module_init(extcon_class_init);
1366
1367 static void __exit extcon_class_exit(void)
1368 {
1369 #if defined(CONFIG_ANDROID)
1370         class_compat_unregister(switch_class);
1371 #endif
1372         class_destroy(extcon_class);
1373 }
1374 module_exit(extcon_class_exit);
1375
1376 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
1377 MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
1378 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
1379 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1380 MODULE_DESCRIPTION("External connector (extcon) class driver");
1381 MODULE_LICENSE("GPL");