drivers/extcon/extcon.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * drivers/extcon/extcon.c - External Connector (extcon) framework.
   4  *
   5  * Copyright (C) 2015 Samsung Electronics
   6  * Author: Chanwoo Choi <cw00.choi@samsung.com>
   7  *
   8  * Copyright (C) 2012 Samsung Electronics
   9  * Author: Donggeun Kim <dg77.kim@samsung.com>
  10  * Author: MyungJoo Ham <myungjoo.ham@samsung.com>
  11  *
  12  * based on android/drivers/switch/switch_class.c
  13  * Copyright (C) 2008 Google, Inc.
  14  * Author: Mike Lockwood <lockwood@android.com>
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/types.h>
  19 #include <linux/init.h>
  20 #include <linux/device.h>
  21 #include <linux/fs.h>
  22 #include <linux/err.h>
  23 #include <linux/of.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysfs.h>
  26
  27 #include "extcon.h"
  28
  29 #define SUPPORTED_CABLE_MAX     32
  30
  31 static const struct __extcon_info {
  32         unsigned int type;
  33         unsigned int id;
  34         const char *name;
  35
  36 } extcon_info[] = {
  37         [EXTCON_NONE] = {
  38                 .type = EXTCON_TYPE_MISC,
  39                 .id = EXTCON_NONE,
  40                 .name = "NONE",
  41         },
  42
  43         /* USB external connector */
  44         [EXTCON_USB] = {
  45                 .type = EXTCON_TYPE_USB,
  46                 .id = EXTCON_USB,
  47                 .name = "USB",
  48         },
  49         [EXTCON_USB_HOST] = {
  50                 .type = EXTCON_TYPE_USB,
  51                 .id = EXTCON_USB_HOST,
  52                 .name = "USB-HOST",
  53         },
  54
  55         /* Charging external connector */
  56         [EXTCON_CHG_USB_SDP] = {
  57                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  58                 .id = EXTCON_CHG_USB_SDP,
  59                 .name = "SDP",
  60         },
  61         [EXTCON_CHG_USB_DCP] = {
  62                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  63                 .id = EXTCON_CHG_USB_DCP,
  64                 .name = "DCP",
  65         },
  66         [EXTCON_CHG_USB_CDP] = {
  67                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  68                 .id = EXTCON_CHG_USB_CDP,
  69                 .name = "CDP",
  70         },
  71         [EXTCON_CHG_USB_ACA] = {
  72                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  73                 .id = EXTCON_CHG_USB_ACA,
  74                 .name = "ACA",
  75         },
  76         [EXTCON_CHG_USB_FAST] = {
  77                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  78                 .id = EXTCON_CHG_USB_FAST,
  79                 .name = "FAST-CHARGER",
  80         },
  81         [EXTCON_CHG_USB_SLOW] = {
  82                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  83                 .id = EXTCON_CHG_USB_SLOW,
  84                 .name = "SLOW-CHARGER",
  85         },
  86         [EXTCON_CHG_WPT] = {
  87                 .type = EXTCON_TYPE_CHG,
  88                 .id = EXTCON_CHG_WPT,
  89                 .name = "WPT",
  90         },
  91         [EXTCON_CHG_USB_PD] = {
  92                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  93                 .id = EXTCON_CHG_USB_PD,
  94                 .name = "PD",
  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 an external connector.
 193  * @edev:               the extcon device
 194  * @cable_index:        the index of this cable in the edev
 195  * @attr_g:             the attribute group for the cable
 196  * @attr_name:          "name" sysfs entry
 197  * @attr_state:         "state" sysfs entry
 198  * @attrs:              the 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
 223 static LIST_HEAD(extcon_dev_list);
 224 static DEFINE_MUTEX(extcon_dev_list_lock);
 225
 226 static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
 227 {
 228         int i = 0;
 229
 230         if (!edev->mutually_exclusive)
 231                 return 0;
 232
 233         for (i = 0; edev->mutually_exclusive[i]; i++) {
 234                 int weight;
 235                 u32 correspondants = new_state & edev->mutually_exclusive[i];
 236
 237                 /* calculate the total number of bits set */
 238                 weight = hweight32(correspondants);
 239                 if (weight > 1)
 240                         return i + 1;
 241         }
 242
 243         return 0;
 244 }
 245
 246 static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id)
 247 {
 248         int i;
 249
 250         /* Find the the index of extcon cable in edev->supported_cable */
 251         for (i = 0; i < edev->max_supported; i++) {
 252                 if (edev->supported_cable[i] == id)
 253                         return i;
 254         }
 255
 256         return -EINVAL;
 257 }
 258
 259 static int get_extcon_type(unsigned int prop)
 260 {
 261         switch (prop) {
 262         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 263                 return EXTCON_TYPE_USB;
 264         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 265                 return EXTCON_TYPE_CHG;
 266         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 267                 return EXTCON_TYPE_JACK;
 268         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 269                 return EXTCON_TYPE_DISP;
 270         default:
 271                 return -EINVAL;
 272         }
 273 }
 274
 275 static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index)
 276 {
 277         return !!(edev->state & BIT(index));
 278 }
 279
 280 static bool is_extcon_changed(struct extcon_dev *edev, int index,
 281                                 bool new_state)
 282 {
 283         int state = !!(edev->state & BIT(index));
 284         return (state != new_state);
 285 }
 286
 287 static bool is_extcon_property_supported(unsigned int id, unsigned int prop)
 288 {
 289         int type;
 290
 291         /* Check whether the property is supported or not. */
 292         type = get_extcon_type(prop);
 293         if (type < 0)
 294                 return false;
 295
 296         /* Check whether a specific extcon id supports the property or not. */
 297         return !!(extcon_info[id].type & type);
 298 }
 299
 300 static int is_extcon_property_capability(struct extcon_dev *edev,
 301                                 unsigned int id, int index,unsigned int prop)
 302 {
 303         struct extcon_cable *cable;
 304         int type, ret;
 305
 306         /* Check whether the property is supported or not. */
 307         type = get_extcon_type(prop);
 308         if (type < 0)
 309                 return type;
 310
 311         cable = &edev->cables[index];
 312
 313         switch (type) {
 314         case EXTCON_TYPE_USB:
 315                 ret = test_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
 316                 break;
 317         case EXTCON_TYPE_CHG:
 318                 ret = test_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
 319                 break;
 320         case EXTCON_TYPE_JACK:
 321                 ret = test_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
 322                 break;
 323         case EXTCON_TYPE_DISP:
 324                 ret = test_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
 325                 break;
 326         default:
 327                 ret = -EINVAL;
 328         }
 329
 330         return ret;
 331 }
 332
 333 static void init_property(struct extcon_dev *edev, unsigned int id, int index)
 334 {
 335         unsigned int type = extcon_info[id].type;
 336         struct extcon_cable *cable = &edev->cables[index];
 337
 338         if (EXTCON_TYPE_USB & type)
 339                 memset(cable->usb_propval, 0, sizeof(cable->usb_propval));
 340         if (EXTCON_TYPE_CHG & type)
 341                 memset(cable->chg_propval, 0, sizeof(cable->chg_propval));
 342         if (EXTCON_TYPE_JACK & type)
 343                 memset(cable->jack_propval, 0, sizeof(cable->jack_propval));
 344         if (EXTCON_TYPE_DISP & type)
 345                 memset(cable->disp_propval, 0, sizeof(cable->disp_propval));
 346 }
 347
 348 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 349                           char *buf)
 350 {
 351         int i, count = 0;
 352         struct extcon_dev *edev = dev_get_drvdata(dev);
 353
 354         if (edev->max_supported == 0)
 355                 return sprintf(buf, "%u\n", edev->state);
 356
 357         for (i = 0; i < edev->max_supported; i++) {
 358                 count += sprintf(buf + count, "%s=%d\n",
 359                                 extcon_info[edev->supported_cable[i]].name,
 360                                  !!(edev->state & BIT(i)));
 361         }
 362
 363         return count;
 364 }
 365 static DEVICE_ATTR_RO(state);
 366
 367 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 368                 char *buf)
 369 {
 370         struct extcon_dev *edev = dev_get_drvdata(dev);
 371
 372         return sprintf(buf, "%s\n", edev->name);
 373 }
 374 static DEVICE_ATTR_RO(name);
 375
 376 static ssize_t cable_name_show(struct device *dev,
 377                                struct device_attribute *attr, char *buf)
 378 {
 379         struct extcon_cable *cable = container_of(attr, struct extcon_cable,
 380                                                   attr_name);
 381         int i = cable->cable_index;
 382
 383         return sprintf(buf, "%s\n",
 384                         extcon_info[cable->edev->supported_cable[i]].name);
 385 }
 386
 387 static ssize_t cable_state_show(struct device *dev,
 388                                 struct device_attribute *attr, char *buf)
 389 {
 390         struct extcon_cable *cable = container_of(attr, struct extcon_cable,
 391                                                   attr_state);
 392
 393         int i = cable->cable_index;
 394
 395         return sprintf(buf, "%d\n",
 396                 extcon_get_state(cable->edev, cable->edev->supported_cable[i]));
 397 }
 398
 399 /**
 400  * extcon_sync() - Synchronize the state for an external connector.
 401  * @edev:       the extcon device
 402  *
 403  * Note that this function send a notification in order to synchronize
 404  * the state and property of an external connector.
 405  *
 406  * Returns 0 if success or error number if fail.
 407  */
 408 int extcon_sync(struct extcon_dev *edev, unsigned int id)
 409 {
 410         char name_buf[120];
 411         char state_buf[120];
 412         char *prop_buf;
 413         char *envp[3];
 414         int env_offset = 0;
 415         int length;
 416         int index;
 417         int state;
 418         unsigned long flags;
 419
 420         if (!edev)
 421                 return -EINVAL;
 422
 423         index = find_cable_index_by_id(edev, id);
 424         if (index < 0)
 425                 return index;
 426
 427         spin_lock_irqsave(&edev->lock, flags);
 428         state = !!(edev->state & BIT(index));
 429         spin_unlock_irqrestore(&edev->lock, flags);
 430
 431         /*
 432          * Call functions in a raw notifier chain for the specific one
 433          * external connector.
 434          */
 435         raw_notifier_call_chain(&edev->nh[index], state, edev);
 436
 437         /*
 438          * Call functions in a raw notifier chain for the all supported
 439          * external connectors.
 440          */
 441         raw_notifier_call_chain(&edev->nh_all, state, edev);
 442
 443         spin_lock_irqsave(&edev->lock, flags);
 444         /* This could be in interrupt handler */
 445         prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
 446         if (!prop_buf) {
 447                 /* Unlock early before uevent */
 448                 spin_unlock_irqrestore(&edev->lock, flags);
 449
 450                 dev_err(&edev->dev, "out of memory in extcon_set_state\n");
 451                 kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE);
 452
 453                 return -ENOMEM;
 454         }
 455
 456         length = name_show(&edev->dev, NULL, prop_buf);
 457         if (length > 0) {
 458                 if (prop_buf[length - 1] == '\n')
 459                         prop_buf[length - 1] = 0;
 460                 snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf);
 461                 envp[env_offset++] = name_buf;
 462         }
 463
 464         length = state_show(&edev->dev, NULL, prop_buf);
 465         if (length > 0) {
 466                 if (prop_buf[length - 1] == '\n')
 467                         prop_buf[length - 1] = 0;
 468                 snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf);
 469                 envp[env_offset++] = state_buf;
 470         }
 471         envp[env_offset] = NULL;
 472
 473         /* Unlock early before uevent */
 474         spin_unlock_irqrestore(&edev->lock, flags);
 475         kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp);
 476         free_page((unsigned long)prop_buf);
 477
 478         return 0;
 479 }
 480 EXPORT_SYMBOL_GPL(extcon_sync);
 481
 482 /**
 483  * extcon_get_state() - Get the state of an external connector.
 484  * @edev:       the extcon device
 485  * @id:         the unique id indicating an external connector
 486  *
 487  * Returns 0 if success or error number if fail.
 488  */
 489 int extcon_get_state(struct extcon_dev *edev, const unsigned int id)
 490 {
 491         int index, state;
 492         unsigned long flags;
 493
 494         if (!edev)
 495                 return -EINVAL;
 496
 497         index = find_cable_index_by_id(edev, id);
 498         if (index < 0)
 499                 return index;
 500
 501         spin_lock_irqsave(&edev->lock, flags);
 502         state = is_extcon_attached(edev, index);
 503         spin_unlock_irqrestore(&edev->lock, flags);
 504
 505         return state;
 506 }
 507 EXPORT_SYMBOL_GPL(extcon_get_state);
 508
 509 /**
 510  * extcon_set_state() - Set the state of an external connector.
 511  * @edev:       the extcon device
 512  * @id:         the unique id indicating an external connector
 513  * @state:      the new state of an external connector.
 514  *              the default semantics is true: attached / false: detached.
 515  *
 516  * Note that this function set the state of an external connector without
 517  * a notification. To synchronize the state of an external connector,
 518  * have to use extcon_set_state_sync() and extcon_sync().
 519  *
 520  * Returns 0 if success or error number if fail.
 521  */
 522 int extcon_set_state(struct extcon_dev *edev, unsigned int id, bool state)
 523 {
 524         unsigned long flags;
 525         int index, ret = 0;
 526
 527         if (!edev)
 528                 return -EINVAL;
 529
 530         index = find_cable_index_by_id(edev, id);
 531         if (index < 0)
 532                 return index;
 533
 534         spin_lock_irqsave(&edev->lock, flags);
 535
 536         /* Check whether the external connector's state is changed. */
 537         if (!is_extcon_changed(edev, index, state))
 538                 goto out;
 539
 540         if (check_mutually_exclusive(edev,
 541                 (edev->state & ~BIT(index)) | (state & BIT(index)))) {
 542                 ret = -EPERM;
 543                 goto out;
 544         }
 545
 546         /*
 547          * Initialize the value of extcon property before setting
 548          * the detached state for an external connector.
 549          */
 550         if (!state)
 551                 init_property(edev, id, index);
 552
 553         /* Update the state for an external connector. */
 554         if (state)
 555                 edev->state |= BIT(index);
 556         else
 557                 edev->state &= ~(BIT(index));
 558 out:
 559         spin_unlock_irqrestore(&edev->lock, flags);
 560
 561         return ret;
 562 }
 563 EXPORT_SYMBOL_GPL(extcon_set_state);
 564
 565 /**
 566  * extcon_set_state_sync() - Set the state of an external connector with sync.
 567  * @edev:       the extcon device
 568  * @id:         the unique id indicating an external connector
 569  * @state:      the new state of external connector.
 570  *              the default semantics is true: attached / false: detached.
 571  *
 572  * Note that this function set the state of external connector
 573  * and synchronize the state by sending a notification.
 574  *
 575  * Returns 0 if success or error number if fail.
 576  */
 577 int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id, bool state)
 578 {
 579         int ret;
 580
 581         ret = extcon_set_state(edev, id, state);
 582         if (ret < 0)
 583                 return ret;
 584
 585         return extcon_sync(edev, id);
 586 }
 587 EXPORT_SYMBOL_GPL(extcon_set_state_sync);
 588
 589 /**
 590  * extcon_get_property() - Get the property value of an external connector.
 591  * @edev:       the extcon device
 592  * @id:         the unique id indicating an external connector
 593  * @prop:       the property id indicating an extcon property
 594  * @prop_val:   the pointer which store the value of extcon property
 595  *
 596  * Note that when getting the property value of external connector,
 597  * the external connector should be attached. If detached state, function
 598  * return 0 without property value. Also, the each property should be
 599  * included in the list of supported properties according to extcon type.
 600  *
 601  * Returns 0 if success or error number if fail.
 602  */
 603 int extcon_get_property(struct extcon_dev *edev, unsigned int id,
 604                                 unsigned int prop,
 605                                 union extcon_property_value *prop_val)
 606 {
 607         struct extcon_cable *cable;
 608         unsigned long flags;
 609         int index, ret = 0;
 610
 611         *prop_val = (union extcon_property_value){0};
 612
 613         if (!edev)
 614                 return -EINVAL;
 615
 616         /* Check whether the property is supported or not */
 617         if (!is_extcon_property_supported(id, prop))
 618                 return -EINVAL;
 619
 620         /* Find the cable index of external connector by using id */
 621         index = find_cable_index_by_id(edev, id);
 622         if (index < 0)
 623                 return index;
 624
 625         spin_lock_irqsave(&edev->lock, flags);
 626
 627         /* Check whether the property is available or not. */
 628         if (!is_extcon_property_capability(edev, id, index, prop)) {
 629                 spin_unlock_irqrestore(&edev->lock, flags);
 630                 return -EPERM;
 631         }
 632
 633         /*
 634          * Check whether the external connector is attached.
 635          * If external connector is detached, the user can not
 636          * get the property value.
 637          */
 638         if (!is_extcon_attached(edev, index)) {
 639                 spin_unlock_irqrestore(&edev->lock, flags);
 640                 return 0;
 641         }
 642
 643         cable = &edev->cables[index];
 644
 645         /* Get the property value according to extcon type */
 646         switch (prop) {
 647         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 648                 *prop_val = cable->usb_propval[prop - EXTCON_PROP_USB_MIN];
 649                 break;
 650         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 651                 *prop_val = cable->chg_propval[prop - EXTCON_PROP_CHG_MIN];
 652                 break;
 653         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 654                 *prop_val = cable->jack_propval[prop - EXTCON_PROP_JACK_MIN];
 655                 break;
 656         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 657                 *prop_val = cable->disp_propval[prop - EXTCON_PROP_DISP_MIN];
 658                 break;
 659         default:
 660                 ret = -EINVAL;
 661                 break;
 662         }
 663
 664         spin_unlock_irqrestore(&edev->lock, flags);
 665
 666         return ret;
 667 }
 668 EXPORT_SYMBOL_GPL(extcon_get_property);
 669
 670 /**
 671  * extcon_set_property() - Set the property value of an external connector.
 672  * @edev:       the extcon device
 673  * @id:         the unique id indicating an external connector
 674  * @prop:       the property id indicating an extcon property
 675  * @prop_val:   the pointer including the new value of extcon property
 676  *
 677  * Note that each property should be included in the list of supported
 678  * properties according to the extcon type.
 679  *
 680  * Returns 0 if success or error number if fail.
 681  */
 682 int extcon_set_property(struct extcon_dev *edev, unsigned int id,
 683                                 unsigned int prop,
 684                                 union extcon_property_value prop_val)
 685 {
 686         struct extcon_cable *cable;
 687         unsigned long flags;
 688         int index, ret = 0;
 689
 690         if (!edev)
 691                 return -EINVAL;
 692
 693         /* Check whether the property is supported or not */
 694         if (!is_extcon_property_supported(id, prop))
 695                 return -EINVAL;
 696
 697         /* Find the cable index of external connector by using id */
 698         index = find_cable_index_by_id(edev, id);
 699         if (index < 0)
 700                 return index;
 701
 702         spin_lock_irqsave(&edev->lock, flags);
 703
 704         /* Check whether the property is available or not. */
 705         if (!is_extcon_property_capability(edev, id, index, prop)) {
 706                 spin_unlock_irqrestore(&edev->lock, flags);
 707                 return -EPERM;
 708         }
 709
 710         cable = &edev->cables[index];
 711
 712         /* Set the property value according to extcon type */
 713         switch (prop) {
 714         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 715                 cable->usb_propval[prop - EXTCON_PROP_USB_MIN] = prop_val;
 716                 break;
 717         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 718                 cable->chg_propval[prop - EXTCON_PROP_CHG_MIN] = prop_val;
 719                 break;
 720         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 721                 cable->jack_propval[prop - EXTCON_PROP_JACK_MIN] = prop_val;
 722                 break;
 723         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 724                 cable->disp_propval[prop - EXTCON_PROP_DISP_MIN] = prop_val;
 725                 break;
 726         default:
 727                 ret = -EINVAL;
 728                 break;
 729         }
 730
 731         spin_unlock_irqrestore(&edev->lock, flags);
 732
 733         return ret;
 734 }
 735 EXPORT_SYMBOL_GPL(extcon_set_property);
 736
 737 /**
 738  * extcon_set_property_sync() - Set property of an external connector with sync.
 739  * @prop_val:   the pointer including the new value of extcon property
 740  *
 741  * Note that when setting the property value of external connector,
 742  * the external connector should be attached. The each property should
 743  * be included in the list of supported properties according to extcon type.
 744  *
 745  * Returns 0 if success or error number if fail.
 746  */
 747 int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id,
 748                                 unsigned int prop,
 749                                 union extcon_property_value prop_val)
 750 {
 751         int ret;
 752
 753         ret = extcon_set_property(edev, id, prop, prop_val);
 754         if (ret < 0)
 755                 return ret;
 756
 757         return extcon_sync(edev, id);
 758 }
 759 EXPORT_SYMBOL_GPL(extcon_set_property_sync);
 760
 761 /**
 762  * extcon_get_property_capability() - Get the capability of the property
 763  *                                      for an external connector.
 764  * @edev:       the extcon device
 765  * @id:         the unique id indicating an external connector
 766  * @prop:       the property id indicating an extcon property
 767  *
 768  * Returns 1 if the property is available or 0 if not available.
 769  */
 770 int extcon_get_property_capability(struct extcon_dev *edev, unsigned int id,
 771                                         unsigned int prop)
 772 {
 773         int index;
 774
 775         if (!edev)
 776                 return -EINVAL;
 777
 778         /* Check whether the property is supported or not */
 779         if (!is_extcon_property_supported(id, prop))
 780                 return -EINVAL;
 781
 782         /* Find the cable index of external connector by using id */
 783         index = find_cable_index_by_id(edev, id);
 784         if (index < 0)
 785                 return index;
 786
 787         return is_extcon_property_capability(edev, id, index, prop);
 788 }
 789 EXPORT_SYMBOL_GPL(extcon_get_property_capability);
 790
 791 /**
 792  * extcon_set_property_capability() - Set the capability of the property
 793  *                                      for an external connector.
 794  * @edev:       the extcon device
 795  * @id:         the unique id indicating an external connector
 796  * @prop:       the property id indicating an extcon property
 797  *
 798  * Note that this function set the capability of the property
 799  * for an external connector in order to mark the bit in capability
 800  * bitmap which mean the available state of the property.
 801  *
 802  * Returns 0 if success or error number if fail.
 803  */
 804 int extcon_set_property_capability(struct extcon_dev *edev, unsigned int id,
 805                                         unsigned int prop)
 806 {
 807         struct extcon_cable *cable;
 808         int index, type, ret = 0;
 809
 810         if (!edev)
 811                 return -EINVAL;
 812
 813         /* Check whether the property is supported or not. */
 814         if (!is_extcon_property_supported(id, prop))
 815                 return -EINVAL;
 816
 817         /* Find the cable index of external connector by using id. */
 818         index = find_cable_index_by_id(edev, id);
 819         if (index < 0)
 820                 return index;
 821
 822         type = get_extcon_type(prop);
 823         if (type < 0)
 824                 return type;
 825
 826         cable = &edev->cables[index];
 827
 828         switch (type) {
 829         case EXTCON_TYPE_USB:
 830                 __set_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
 831                 break;
 832         case EXTCON_TYPE_CHG:
 833                 __set_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
 834                 break;
 835         case EXTCON_TYPE_JACK:
 836                 __set_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
 837                 break;
 838         case EXTCON_TYPE_DISP:
 839                 __set_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
 840                 break;
 841         default:
 842                 ret = -EINVAL;
 843         }
 844
 845         return ret;
 846 }
 847 EXPORT_SYMBOL_GPL(extcon_set_property_capability);
 848
 849 /**
 850  * extcon_get_extcon_dev() - Get the extcon device instance from the name.
 851  * @extcon_name:        the extcon name provided with extcon_dev_register()
 852  *
 853  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
 854  */
 855 struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
 856 {
 857         struct extcon_dev *sd;
 858
 859         if (!extcon_name)
 860                 return ERR_PTR(-EINVAL);
 861
 862         mutex_lock(&extcon_dev_list_lock);
 863         list_for_each_entry(sd, &extcon_dev_list, entry) {
 864                 if (!strcmp(sd->name, extcon_name))
 865                         goto out;
 866         }
 867         sd = NULL;
 868 out:
 869         mutex_unlock(&extcon_dev_list_lock);
 870         return sd;
 871 }
 872 EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
 873
 874 /**
 875  * extcon_register_notifier() - Register a notifier block to get notified by
 876  *                              any state changes from the extcon.
 877  * @edev:       the extcon device
 878  * @id:         the unique id indicating an external connector
 879  * @nb:         a notifier block to be registered
 880  *
 881  * Note that the second parameter given to the callback of nb (val) is
 882  * the current state of an external connector and the third pameter
 883  * is the pointer of extcon device.
 884  *
 885  * Returns 0 if success or error number if fail.
 886  */
 887 int extcon_register_notifier(struct extcon_dev *edev, unsigned int id,
 888                              struct notifier_block *nb)
 889 {
 890         unsigned long flags;
 891         int ret, idx;
 892
 893         if (!edev || !nb)
 894                 return -EINVAL;
 895
 896         idx = find_cable_index_by_id(edev, id);
 897         if (idx < 0)
 898                 return idx;
 899
 900         spin_lock_irqsave(&edev->lock, flags);
 901         ret = raw_notifier_chain_register(&edev->nh[idx], nb);
 902         spin_unlock_irqrestore(&edev->lock, flags);
 903
 904         return ret;
 905 }
 906 EXPORT_SYMBOL_GPL(extcon_register_notifier);
 907
 908 /**
 909  * extcon_unregister_notifier() - Unregister a notifier block from the extcon.
 910  * @edev:       the extcon device
 911  * @id:         the unique id indicating an external connector
 912  * @nb:         a notifier block to be registered
 913  *
 914  * Returns 0 if success or error number if fail.
 915  */
 916 int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id,
 917                                 struct notifier_block *nb)
 918 {
 919         unsigned long flags;
 920         int ret, idx;
 921
 922         if (!edev || !nb)
 923                 return -EINVAL;
 924
 925         idx = find_cable_index_by_id(edev, id);
 926         if (idx < 0)
 927                 return idx;
 928
 929         spin_lock_irqsave(&edev->lock, flags);
 930         ret = raw_notifier_chain_unregister(&edev->nh[idx], nb);
 931         spin_unlock_irqrestore(&edev->lock, flags);
 932
 933         return ret;
 934 }
 935 EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
 936
 937 /**
 938  * extcon_register_notifier_all() - Register a notifier block for all connectors.
 939  * @edev:       the extcon device
 940  * @nb:         a notifier block to be registered
 941  *
 942  * Note that this function registers a notifier block in order to receive
 943  * the state change of all supported external connectors from extcon device.
 944  * And the second parameter given to the callback of nb (val) is
 945  * the current state and the third pameter is the pointer of extcon device.
 946  *
 947  * Returns 0 if success or error number if fail.
 948  */
 949 int extcon_register_notifier_all(struct extcon_dev *edev,
 950                                 struct notifier_block *nb)
 951 {
 952         unsigned long flags;
 953         int ret;
 954
 955         if (!edev || !nb)
 956                 return -EINVAL;
 957
 958         spin_lock_irqsave(&edev->lock, flags);
 959         ret = raw_notifier_chain_register(&edev->nh_all, nb);
 960         spin_unlock_irqrestore(&edev->lock, flags);
 961
 962         return ret;
 963 }
 964 EXPORT_SYMBOL_GPL(extcon_register_notifier_all);
 965
 966 /**
 967  * extcon_unregister_notifier_all() - Unregister a notifier block from extcon.
 968  * @edev:       the extcon device
 969  * @nb:         a notifier block to be registered
 970  *
 971  * Returns 0 if success or error number if fail.
 972  */
 973 int extcon_unregister_notifier_all(struct extcon_dev *edev,
 974                                 struct notifier_block *nb)
 975 {
 976         unsigned long flags;
 977         int ret;
 978
 979         if (!edev || !nb)
 980                 return -EINVAL;
 981
 982         spin_lock_irqsave(&edev->lock, flags);
 983         ret = raw_notifier_chain_unregister(&edev->nh_all, nb);
 984         spin_unlock_irqrestore(&edev->lock, flags);
 985
 986         return ret;
 987 }
 988 EXPORT_SYMBOL_GPL(extcon_unregister_notifier_all);
 989
 990 static struct attribute *extcon_attrs[] = {
 991         &dev_attr_state.attr,
 992         &dev_attr_name.attr,
 993         NULL,
 994 };
 995 ATTRIBUTE_GROUPS(extcon);
 996
 997 static int create_extcon_class(void)
 998 {
 999         if (!extcon_class) {
1000                 extcon_class = class_create(THIS_MODULE, "extcon");
1001                 if (IS_ERR(extcon_class))
1002                         return PTR_ERR(extcon_class);
1003                 extcon_class->dev_groups = extcon_groups;
1004         }
1005
1006         return 0;
1007 }
1008
1009 static void extcon_dev_release(struct device *dev)
1010 {
1011 }
1012
1013 static const char *muex_name = "mutually_exclusive";
1014 static void dummy_sysfs_dev_release(struct device *dev)
1015 {
1016 }
1017
1018 /*
1019  * extcon_dev_allocate() - Allocate the memory of extcon device.
1020  * @supported_cable:    the array of the supported external connectors
1021  *                      ending with EXTCON_NONE.
1022  *
1023  * Note that this function allocates the memory for extcon device
1024  * and initialize default setting for the extcon device.
1025  *
1026  * Returns the pointer memory of allocated extcon_dev if success
1027  * or ERR_PTR(err) if fail.
1028  */
1029 struct extcon_dev *extcon_dev_allocate(const unsigned int *supported_cable)
1030 {
1031         struct extcon_dev *edev;
1032
1033         if (!supported_cable)
1034                 return ERR_PTR(-EINVAL);
1035
1036         edev = kzalloc(sizeof(*edev), GFP_KERNEL);
1037         if (!edev)
1038                 return ERR_PTR(-ENOMEM);
1039
1040         edev->max_supported = 0;
1041         edev->supported_cable = supported_cable;
1042
1043         return edev;
1044 }
1045
1046 /*
1047  * extcon_dev_free() - Free the memory of extcon device.
1048  * @edev:       the extcon device
1049  */
1050 void extcon_dev_free(struct extcon_dev *edev)
1051 {
1052         kfree(edev);
1053 }
1054 EXPORT_SYMBOL_GPL(extcon_dev_free);
1055
1056 /**
1057  * extcon_dev_register() - Register an new extcon device
1058  * @edev:       the extcon device to be registered
1059  *
1060  * Among the members of edev struct, please set the "user initializing data"
1061  * do not set the values of "internal data", which are initialized by
1062  * this function.
1063  *
1064  * Note that before calling this funciton, have to allocate the memory
1065  * of an extcon device by using the extcon_dev_allocate(). And the extcon
1066  * dev should include the supported_cable information.
1067  *
1068  * Returns 0 if success or error number if fail.
1069  */
1070 int extcon_dev_register(struct extcon_dev *edev)
1071 {
1072         int ret, index = 0;
1073         static atomic_t edev_no = ATOMIC_INIT(-1);
1074
1075         if (!extcon_class) {
1076                 ret = create_extcon_class();
1077                 if (ret < 0)
1078                         return ret;
1079         }
1080
1081         if (!edev || !edev->supported_cable)
1082                 return -EINVAL;
1083
1084         for (; edev->supported_cable[index] != EXTCON_NONE; index++);
1085
1086         edev->max_supported = index;
1087         if (index > SUPPORTED_CABLE_MAX) {
1088                 dev_err(&edev->dev,
1089                         "exceed the maximum number of supported cables\n");
1090                 return -EINVAL;
1091         }
1092
1093         edev->dev.class = extcon_class;
1094         edev->dev.release = extcon_dev_release;
1095
1096         edev->name = dev_name(edev->dev.parent);
1097         if (IS_ERR_OR_NULL(edev->name)) {
1098                 dev_err(&edev->dev,
1099                         "extcon device name is null\n");
1100                 return -EINVAL;
1101         }
1102         dev_set_name(&edev->dev, "extcon%lu",
1103                         (unsigned long)atomic_inc_return(&edev_no));
1104
1105         if (edev->max_supported) {
1106                 char *str;
1107                 struct extcon_cable *cable;
1108
1109                 edev->cables = kcalloc(edev->max_supported,
1110                                        sizeof(struct extcon_cable),
1111                                        GFP_KERNEL);
1112                 if (!edev->cables) {
1113                         ret = -ENOMEM;
1114                         goto err_sysfs_alloc;
1115                 }
1116                 for (index = 0; index < edev->max_supported; index++) {
1117                         cable = &edev->cables[index];
1118
1119                         str = kasprintf(GFP_KERNEL, "cable.%d", index);
1120                         if (!str) {
1121                                 for (index--; index >= 0; index--) {
1122                                         cable = &edev->cables[index];
1123                                         kfree(cable->attr_g.name);
1124                                 }
1125                                 ret = -ENOMEM;
1126
1127                                 goto err_alloc_cables;
1128                         }
1129
1130                         cable->edev = edev;
1131                         cable->cable_index = index;
1132                         cable->attrs[0] = &cable->attr_name.attr;
1133                         cable->attrs[1] = &cable->attr_state.attr;
1134                         cable->attrs[2] = NULL;
1135                         cable->attr_g.name = str;
1136                         cable->attr_g.attrs = cable->attrs;
1137
1138                         sysfs_attr_init(&cable->attr_name.attr);
1139                         cable->attr_name.attr.name = "name";
1140                         cable->attr_name.attr.mode = 0444;
1141                         cable->attr_name.show = cable_name_show;
1142
1143                         sysfs_attr_init(&cable->attr_state.attr);
1144                         cable->attr_state.attr.name = "state";
1145                         cable->attr_state.attr.mode = 0444;
1146                         cable->attr_state.show = cable_state_show;
1147                 }
1148         }
1149
1150         if (edev->max_supported && edev->mutually_exclusive) {
1151                 char *name;
1152
1153                 /* Count the size of mutually_exclusive array */
1154                 for (index = 0; edev->mutually_exclusive[index]; index++)
1155                         ;
1156
1157                 edev->attrs_muex = kcalloc(index + 1,
1158                                            sizeof(struct attribute *),
1159                                            GFP_KERNEL);
1160                 if (!edev->attrs_muex) {
1161                         ret = -ENOMEM;
1162                         goto err_muex;
1163                 }
1164
1165                 edev->d_attrs_muex = kcalloc(index,
1166                                              sizeof(struct device_attribute),
1167                                              GFP_KERNEL);
1168                 if (!edev->d_attrs_muex) {
1169                         ret = -ENOMEM;
1170                         kfree(edev->attrs_muex);
1171                         goto err_muex;
1172                 }
1173
1174                 for (index = 0; edev->mutually_exclusive[index]; index++) {
1175                         name = kasprintf(GFP_KERNEL, "0x%x",
1176                                          edev->mutually_exclusive[index]);
1177                         if (!name) {
1178                                 for (index--; index >= 0; index--) {
1179                                         kfree(edev->d_attrs_muex[index].attr.
1180                                               name);
1181                                 }
1182                                 kfree(edev->d_attrs_muex);
1183                                 kfree(edev->attrs_muex);
1184                                 ret = -ENOMEM;
1185                                 goto err_muex;
1186                         }
1187                         sysfs_attr_init(&edev->d_attrs_muex[index].attr);
1188                         edev->d_attrs_muex[index].attr.name = name;
1189                         edev->d_attrs_muex[index].attr.mode = 0000;
1190                         edev->attrs_muex[index] = &edev->d_attrs_muex[index]
1191                                                         .attr;
1192                 }
1193                 edev->attr_g_muex.name = muex_name;
1194                 edev->attr_g_muex.attrs = edev->attrs_muex;
1195
1196         }
1197
1198         if (edev->max_supported) {
1199                 edev->extcon_dev_type.groups =
1200                         kcalloc(edev->max_supported + 2,
1201                                 sizeof(struct attribute_group *),
1202                                 GFP_KERNEL);
1203                 if (!edev->extcon_dev_type.groups) {
1204                         ret = -ENOMEM;
1205                         goto err_alloc_groups;
1206                 }
1207
1208                 edev->extcon_dev_type.name = dev_name(&edev->dev);
1209                 edev->extcon_dev_type.release = dummy_sysfs_dev_release;
1210
1211                 for (index = 0; index < edev->max_supported; index++)
1212                         edev->extcon_dev_type.groups[index] =
1213                                 &edev->cables[index].attr_g;
1214                 if (edev->mutually_exclusive)
1215                         edev->extcon_dev_type.groups[index] =
1216                                 &edev->attr_g_muex;
1217
1218                 edev->dev.type = &edev->extcon_dev_type;
1219         }
1220
1221         ret = device_register(&edev->dev);
1222         if (ret) {
1223                 put_device(&edev->dev);
1224                 goto err_dev;
1225         }
1226
1227         spin_lock_init(&edev->lock);
1228         edev->nh = devm_kcalloc(&edev->dev, edev->max_supported,
1229                                 sizeof(*edev->nh), GFP_KERNEL);
1230         if (!edev->nh) {
1231                 ret = -ENOMEM;
1232                 device_unregister(&edev->dev);
1233                 goto err_dev;
1234         }
1235
1236         for (index = 0; index < edev->max_supported; index++)
1237                 RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]);
1238
1239         RAW_INIT_NOTIFIER_HEAD(&edev->nh_all);
1240
1241         dev_set_drvdata(&edev->dev, edev);
1242         edev->state = 0;
1243
1244         mutex_lock(&extcon_dev_list_lock);
1245         list_add(&edev->entry, &extcon_dev_list);
1246         mutex_unlock(&extcon_dev_list_lock);
1247
1248         return 0;
1249
1250 err_dev:
1251         if (edev->max_supported)
1252                 kfree(edev->extcon_dev_type.groups);
1253 err_alloc_groups:
1254         if (edev->max_supported && edev->mutually_exclusive) {
1255                 for (index = 0; edev->mutually_exclusive[index]; index++)
1256                         kfree(edev->d_attrs_muex[index].attr.name);
1257                 kfree(edev->d_attrs_muex);
1258                 kfree(edev->attrs_muex);
1259         }
1260 err_muex:
1261         for (index = 0; index < edev->max_supported; index++)
1262                 kfree(edev->cables[index].attr_g.name);
1263 err_alloc_cables:
1264         if (edev->max_supported)
1265                 kfree(edev->cables);
1266 err_sysfs_alloc:
1267         return ret;
1268 }
1269 EXPORT_SYMBOL_GPL(extcon_dev_register);
1270
1271 /**
1272  * extcon_dev_unregister() - Unregister the extcon device.
1273  * @edev:       the extcon device to be unregistered.
1274  *
1275  * Note that this does not call kfree(edev) because edev was not allocated
1276  * by this class.
1277  */
1278 void extcon_dev_unregister(struct extcon_dev *edev)
1279 {
1280         int index;
1281
1282         if (!edev)
1283                 return;
1284
1285         mutex_lock(&extcon_dev_list_lock);
1286         list_del(&edev->entry);
1287         mutex_unlock(&extcon_dev_list_lock);
1288
1289         if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
1290                 dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
1291                                 dev_name(&edev->dev));
1292                 return;
1293         }
1294
1295         device_unregister(&edev->dev);
1296
1297         if (edev->mutually_exclusive && edev->max_supported) {
1298                 for (index = 0; edev->mutually_exclusive[index];
1299                                 index++)
1300                         kfree(edev->d_attrs_muex[index].attr.name);
1301                 kfree(edev->d_attrs_muex);
1302                 kfree(edev->attrs_muex);
1303         }
1304
1305         for (index = 0; index < edev->max_supported; index++)
1306                 kfree(edev->cables[index].attr_g.name);
1307
1308         if (edev->max_supported) {
1309                 kfree(edev->extcon_dev_type.groups);
1310                 kfree(edev->cables);
1311         }
1312
1313         put_device(&edev->dev);
1314 }
1315 EXPORT_SYMBOL_GPL(extcon_dev_unregister);
1316
1317 #ifdef CONFIG_OF
1318
1319 /*
1320  * extcon_find_edev_by_node - Find the extcon device from devicetree.
1321  * @node        : OF node identifying edev
1322  *
1323  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
1324  */
1325 struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1326 {
1327         struct extcon_dev *edev;
1328
1329         mutex_lock(&extcon_dev_list_lock);
1330         list_for_each_entry(edev, &extcon_dev_list, entry)
1331                 if (edev->dev.parent && edev->dev.parent->of_node == node)
1332                         goto out;
1333         edev = ERR_PTR(-EPROBE_DEFER);
1334 out:
1335         mutex_unlock(&extcon_dev_list_lock);
1336
1337         return edev;
1338 }
1339
1340 /*
1341  * extcon_get_edev_by_phandle - Get the extcon device from devicetree.
1342  * @dev         : the instance to the given device
1343  * @index       : the index into list of extcon_dev
1344  *
1345  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
1346  */
1347 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1348 {
1349         struct device_node *node;
1350         struct extcon_dev *edev;
1351
1352         if (!dev)
1353                 return ERR_PTR(-EINVAL);
1354
1355         if (!dev->of_node) {
1356                 dev_dbg(dev, "device does not have a device node entry\n");
1357                 return ERR_PTR(-EINVAL);
1358         }
1359
1360         node = of_parse_phandle(dev->of_node, "extcon", index);
1361         if (!node) {
1362                 dev_dbg(dev, "failed to get phandle in %pOF node\n",
1363                         dev->of_node);
1364                 return ERR_PTR(-ENODEV);
1365         }
1366
1367         edev = extcon_find_edev_by_node(node);
1368         of_node_put(node);
1369
1370         return edev;
1371 }
1372
1373 #else
1374
1375 struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1376 {
1377         return ERR_PTR(-ENOSYS);
1378 }
1379
1380 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1381 {
1382         return ERR_PTR(-ENOSYS);
1383 }
1384
1385 #endif /* CONFIG_OF */
1386
1387 EXPORT_SYMBOL_GPL(extcon_find_edev_by_node);
1388 EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
1389
1390 /**
1391  * extcon_get_edev_name() - Get the name of the extcon device.
1392  * @edev:       the extcon device
1393  */
1394 const char *extcon_get_edev_name(struct extcon_dev *edev)
1395 {
1396         return !edev ? NULL : edev->name;
1397 }
1398 EXPORT_SYMBOL_GPL(extcon_get_edev_name);
1399
1400 static int __init extcon_class_init(void)
1401 {
1402         return create_extcon_class();
1403 }
1404 module_init(extcon_class_init);
1405
1406 static void __exit extcon_class_exit(void)
1407 {
1408         class_destroy(extcon_class);
1409 }
1410 module_exit(extcon_class_exit);
1411
1412 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
1413 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1414 MODULE_DESCRIPTION("External Connector (extcon) framework");
1415 MODULE_LICENSE("GPL v2");