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   1/*
   2 * drivers/extcon/extcon.c - External Connector (extcon) framework.
   3 *
   4 * Copyright (C) 2015 Samsung Electronics
   5 * Author: Chanwoo Choi <cw00.choi@samsung.com>
   6 *
   7 * Copyright (C) 2012 Samsung Electronics
   8 * Author: Donggeun Kim <dg77.kim@samsung.com>
   9 * Author: MyungJoo Ham <myungjoo.ham@samsung.com>
  10 *
  11 * based on android/drivers/switch/switch_class.c
  12 * Copyright (C) 2008 Google, Inc.
  13 * Author: Mike Lockwood <lockwood@android.com>
  14 *
  15 * This software is licensed under the terms of the GNU General Public
  16 * License version 2, as published by the Free Software Foundation, and
  17 * may be copied, distributed, and modified under those terms.
  18 *
  19 * This program is distributed in the hope that it will be useful,
  20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22 * GNU General Public License for more details.
  23 */
  24
  25#include <linux/module.h>
  26#include <linux/types.h>
  27#include <linux/init.h>
  28#include <linux/device.h>
  29#include <linux/fs.h>
  30#include <linux/err.h>
  31#include <linux/of.h>
  32#include <linux/slab.h>
  33#include <linux/sysfs.h>
  34
  35#include "extcon.h"
  36
  37#define SUPPORTED_CABLE_MAX	32
  38
  39static const struct __extcon_info {
  40	unsigned int type;
  41	unsigned int id;
  42	const char *name;
  43
  44} extcon_info[] = {
  45	[EXTCON_NONE] = {
  46		.type = EXTCON_TYPE_MISC,
  47		.id = EXTCON_NONE,
  48		.name = "NONE",
  49	},
  50
  51	/* USB external connector */
  52	[EXTCON_USB] = {
  53		.type = EXTCON_TYPE_USB,
  54		.id = EXTCON_USB,
  55		.name = "USB",
  56	},
  57	[EXTCON_USB_HOST] = {
  58		.type = EXTCON_TYPE_USB,
  59		.id = EXTCON_USB_HOST,
  60		.name = "USB-HOST",
  61	},
  62
  63	/* Charging external connector */
  64	[EXTCON_CHG_USB_SDP] = {
  65		.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  66		.id = EXTCON_CHG_USB_SDP,
  67		.name = "SDP",
  68	},
  69	[EXTCON_CHG_USB_DCP] = {
  70		.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  71		.id = EXTCON_CHG_USB_DCP,
  72		.name = "DCP",
  73	},
  74	[EXTCON_CHG_USB_CDP] = {
  75		.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  76		.id = EXTCON_CHG_USB_CDP,
  77		.name = "CDP",
  78	},
  79	[EXTCON_CHG_USB_ACA] = {
  80		.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  81		.id = EXTCON_CHG_USB_ACA,
  82		.name = "ACA",
  83	},
  84	[EXTCON_CHG_USB_FAST] = {
  85		.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  86		.id = EXTCON_CHG_USB_FAST,
  87		.name = "FAST-CHARGER",
  88	},
  89	[EXTCON_CHG_USB_SLOW] = {
  90		.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
  91		.id = EXTCON_CHG_USB_SLOW,
  92		.name = "SLOW-CHARGER",
  93	},
  94	[EXTCON_CHG_WPT] = {
  95		.type = EXTCON_TYPE_CHG,
  96		.id = EXTCON_CHG_WPT,
  97		.name = "WPT",
  98	},
  99	[EXTCON_CHG_USB_PD] = {
 100		.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
 101		.id = EXTCON_CHG_USB_PD,
 102		.name = "PD",
 103	},
 104
 105	/* Jack external connector */
 106	[EXTCON_JACK_MICROPHONE] = {
 107		.type = EXTCON_TYPE_JACK,
 108		.id = EXTCON_JACK_MICROPHONE,
 109		.name = "MICROPHONE",
 110	},
 111	[EXTCON_JACK_HEADPHONE] = {
 112		.type = EXTCON_TYPE_JACK,
 113		.id = EXTCON_JACK_HEADPHONE,
 114		.name = "HEADPHONE",
 115	},
 116	[EXTCON_JACK_LINE_IN] = {
 117		.type = EXTCON_TYPE_JACK,
 118		.id = EXTCON_JACK_LINE_IN,
 119		.name = "LINE-IN",
 120	},
 121	[EXTCON_JACK_LINE_OUT] = {
 122		.type = EXTCON_TYPE_JACK,
 123		.id = EXTCON_JACK_LINE_OUT,
 124		.name = "LINE-OUT",
 125	},
 126	[EXTCON_JACK_VIDEO_IN] = {
 127		.type = EXTCON_TYPE_JACK,
 128		.id = EXTCON_JACK_VIDEO_IN,
 129		.name = "VIDEO-IN",
 130	},
 131	[EXTCON_JACK_VIDEO_OUT] = {
 132		.type = EXTCON_TYPE_JACK,
 133		.id = EXTCON_JACK_VIDEO_OUT,
 134		.name = "VIDEO-OUT",
 135	},
 136	[EXTCON_JACK_SPDIF_IN] = {
 137		.type = EXTCON_TYPE_JACK,
 138		.id = EXTCON_JACK_SPDIF_IN,
 139		.name = "SPDIF-IN",
 140	},
 141	[EXTCON_JACK_SPDIF_OUT] = {
 142		.type = EXTCON_TYPE_JACK,
 143		.id = EXTCON_JACK_SPDIF_OUT,
 144		.name = "SPDIF-OUT",
 145	},
 146
 147	/* Display external connector */
 148	[EXTCON_DISP_HDMI] = {
 149		.type = EXTCON_TYPE_DISP,
 150		.id = EXTCON_DISP_HDMI,
 151		.name = "HDMI",
 152	},
 153	[EXTCON_DISP_MHL] = {
 154		.type = EXTCON_TYPE_DISP,
 155		.id = EXTCON_DISP_MHL,
 156		.name = "MHL",
 157	},
 158	[EXTCON_DISP_DVI] = {
 159		.type = EXTCON_TYPE_DISP,
 160		.id = EXTCON_DISP_DVI,
 161		.name = "DVI",
 162	},
 163	[EXTCON_DISP_VGA] = {
 164		.type = EXTCON_TYPE_DISP,
 165		.id = EXTCON_DISP_VGA,
 166		.name = "VGA",
 167	},
 168	[EXTCON_DISP_DP] = {
 169		.type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
 170		.id = EXTCON_DISP_DP,
 171		.name = "DP",
 172	},
 173	[EXTCON_DISP_HMD] = {
 174		.type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
 175		.id = EXTCON_DISP_HMD,
 176		.name = "HMD",
 177	},
 178
 179	/* Miscellaneous external connector */
 180	[EXTCON_DOCK] = {
 181		.type = EXTCON_TYPE_MISC,
 182		.id = EXTCON_DOCK,
 183		.name = "DOCK",
 184	},
 185	[EXTCON_JIG] = {
 186		.type = EXTCON_TYPE_MISC,
 187		.id = EXTCON_JIG,
 188		.name = "JIG",
 189	},
 190	[EXTCON_MECHANICAL] = {
 191		.type = EXTCON_TYPE_MISC,
 192		.id = EXTCON_MECHANICAL,
 193		.name = "MECHANICAL",
 194	},
 195
 196	{ /* sentinel */ }
 197};
 198
 199/**
 200 * struct extcon_cable - An internal data for an external connector.
 201 * @edev:		the extcon device
 202 * @cable_index:	the index of this cable in the edev
 203 * @attr_g:		the attribute group for the cable
 204 * @attr_name:		"name" sysfs entry
 205 * @attr_state:		"state" sysfs entry
 206 * @attrs:		the array pointing to attr_name and attr_state for attr_g
 207 */
 208struct extcon_cable {
 209	struct extcon_dev *edev;
 210	int cable_index;
 211
 212	struct attribute_group attr_g;
 213	struct device_attribute attr_name;
 214	struct device_attribute attr_state;
 215
 216	struct attribute *attrs[3]; /* to be fed to attr_g.attrs */
 217
 218	union extcon_property_value usb_propval[EXTCON_PROP_USB_CNT];
 219	union extcon_property_value chg_propval[EXTCON_PROP_CHG_CNT];
 220	union extcon_property_value jack_propval[EXTCON_PROP_JACK_CNT];
 221	union extcon_property_value disp_propval[EXTCON_PROP_DISP_CNT];
 222
 223	unsigned long usb_bits[BITS_TO_LONGS(EXTCON_PROP_USB_CNT)];
 224	unsigned long chg_bits[BITS_TO_LONGS(EXTCON_PROP_CHG_CNT)];
 225	unsigned long jack_bits[BITS_TO_LONGS(EXTCON_PROP_JACK_CNT)];
 226	unsigned long disp_bits[BITS_TO_LONGS(EXTCON_PROP_DISP_CNT)];
 227};
 228
 229static struct class *extcon_class;
 230
 231static LIST_HEAD(extcon_dev_list);
 232static DEFINE_MUTEX(extcon_dev_list_lock);
 233
 234static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
 235{
 236	int i = 0;
 237
 238	if (!edev->mutually_exclusive)
 239		return 0;
 240
 241	for (i = 0; edev->mutually_exclusive[i]; i++) {
 242		int weight;
 243		u32 correspondants = new_state & edev->mutually_exclusive[i];
 244
 245		/* calculate the total number of bits set */
 246		weight = hweight32(correspondants);
 247		if (weight > 1)
 248			return i + 1;
 249	}
 250
 251	return 0;
 252}
 253
 254static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id)
 255{
 256	int i;
 257
 258	/* Find the the index of extcon cable in edev->supported_cable */
 259	for (i = 0; i < edev->max_supported; i++) {
 260		if (edev->supported_cable[i] == id)
 261			return i;
 262	}
 263
 264	return -EINVAL;
 265}
 266
 267static int get_extcon_type(unsigned int prop)
 268{
 269	switch (prop) {
 270	case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 271		return EXTCON_TYPE_USB;
 272	case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 273		return EXTCON_TYPE_CHG;
 274	case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 275		return EXTCON_TYPE_JACK;
 276	case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 277		return EXTCON_TYPE_DISP;
 278	default:
 279		return -EINVAL;
 280	}
 281}
 282
 283static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index)
 284{
 285	return !!(edev->state & BIT(index));
 286}
 287
 288static bool is_extcon_changed(struct extcon_dev *edev, int index,
 289				bool new_state)
 290{
 291	int state = !!(edev->state & BIT(index));
 292	return (state != new_state);
 293}
 294
 295static bool is_extcon_property_supported(unsigned int id, unsigned int prop)
 296{
 297	int type;
 298
 299	/* Check whether the property is supported or not. */
 300	type = get_extcon_type(prop);
 301	if (type < 0)
 302		return false;
 303
 304	/* Check whether a specific extcon id supports the property or not. */
 305	return !!(extcon_info[id].type & type);
 306}
 307
 308static int is_extcon_property_capability(struct extcon_dev *edev,
 309				unsigned int id, int index,unsigned int prop)
 310{
 311	struct extcon_cable *cable;
 312	int type, ret;
 313
 314	/* Check whether the property is supported or not. */
 315	type = get_extcon_type(prop);
 316	if (type < 0)
 317		return type;
 318
 319	cable = &edev->cables[index];
 320
 321	switch (type) {
 322	case EXTCON_TYPE_USB:
 323		ret = test_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
 324		break;
 325	case EXTCON_TYPE_CHG:
 326		ret = test_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
 327		break;
 328	case EXTCON_TYPE_JACK:
 329		ret = test_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
 330		break;
 331	case EXTCON_TYPE_DISP:
 332		ret = test_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
 333		break;
 334	default:
 335		ret = -EINVAL;
 336	}
 337
 338	return ret;
 339}
 340
 341static void init_property(struct extcon_dev *edev, unsigned int id, int index)
 342{
 343	unsigned int type = extcon_info[id].type;
 344	struct extcon_cable *cable = &edev->cables[index];
 345
 346	if (EXTCON_TYPE_USB & type)
 347		memset(cable->usb_propval, 0, sizeof(cable->usb_propval));
 348	if (EXTCON_TYPE_CHG & type)
 349		memset(cable->chg_propval, 0, sizeof(cable->chg_propval));
 350	if (EXTCON_TYPE_JACK & type)
 351		memset(cable->jack_propval, 0, sizeof(cable->jack_propval));
 352	if (EXTCON_TYPE_DISP & type)
 353		memset(cable->disp_propval, 0, sizeof(cable->disp_propval));
 354}
 355
 356static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 357			  char *buf)
 358{
 359	int i, count = 0;
 360	struct extcon_dev *edev = dev_get_drvdata(dev);
 361
 362	if (edev->max_supported == 0)
 363		return sprintf(buf, "%u\n", edev->state);
 364
 365	for (i = 0; i < edev->max_supported; i++) {
 366		count += sprintf(buf + count, "%s=%d\n",
 367				extcon_info[edev->supported_cable[i]].name,
 368				 !!(edev->state & BIT(i)));
 369	}
 370
 371	return count;
 372}
 373static DEVICE_ATTR_RO(state);
 374
 375static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 376		char *buf)
 377{
 378	struct extcon_dev *edev = dev_get_drvdata(dev);
 379
 380	return sprintf(buf, "%s\n", edev->name);
 381}
 382static DEVICE_ATTR_RO(name);
 383
 384static ssize_t cable_name_show(struct device *dev,
 385			       struct device_attribute *attr, char *buf)
 386{
 387	struct extcon_cable *cable = container_of(attr, struct extcon_cable,
 388						  attr_name);
 389	int i = cable->cable_index;
 390
 391	return sprintf(buf, "%s\n",
 392			extcon_info[cable->edev->supported_cable[i]].name);
 393}
 394
 395static ssize_t cable_state_show(struct device *dev,
 396				struct device_attribute *attr, char *buf)
 397{
 398	struct extcon_cable *cable = container_of(attr, struct extcon_cable,
 399						  attr_state);
 400
 401	int i = cable->cable_index;
 402
 403	return sprintf(buf, "%d\n",
 404		extcon_get_state(cable->edev, cable->edev->supported_cable[i]));
 405}
 406
 407/**
 408 * extcon_sync() - Synchronize the state for an external connector.
 409 * @edev:	the extcon device
 410 *
 411 * Note that this function send a notification in order to synchronize
 412 * the state and property of an external connector.
 413 *
 414 * Returns 0 if success or error number if fail.
 415 */
 416int extcon_sync(struct extcon_dev *edev, unsigned int id)
 417{
 418	char name_buf[120];
 419	char state_buf[120];
 420	char *prop_buf;
 421	char *envp[3];
 422	int env_offset = 0;
 423	int length;
 424	int index;
 425	int state;
 426	unsigned long flags;
 427
 428	if (!edev)
 429		return -EINVAL;
 430
 431	index = find_cable_index_by_id(edev, id);
 432	if (index < 0)
 433		return index;
 434
 435	spin_lock_irqsave(&edev->lock, flags);
 436
 437	state = !!(edev->state & BIT(index));
 438
 439	/*
 440	 * Call functions in a raw notifier chain for the specific one
 441	 * external connector.
 442	 */
 443	raw_notifier_call_chain(&edev->nh[index], state, edev);
 444
 445	/*
 446	 * Call functions in a raw notifier chain for the all supported
 447	 * external connectors.
 448	 */
 449	raw_notifier_call_chain(&edev->nh_all, state, edev);
 450
 451	/* This could be in interrupt handler */
 452	prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
 453	if (!prop_buf) {
 454		/* Unlock early before uevent */
 455		spin_unlock_irqrestore(&edev->lock, flags);
 456
 457		dev_err(&edev->dev, "out of memory in extcon_set_state\n");
 458		kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE);
 459
 460		return -ENOMEM;
 461	}
 462
 463	length = name_show(&edev->dev, NULL, prop_buf);
 464	if (length > 0) {
 465		if (prop_buf[length - 1] == '\n')
 466			prop_buf[length - 1] = 0;
 467		snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf);
 468		envp[env_offset++] = name_buf;
 469	}
 470
 471	length = state_show(&edev->dev, NULL, prop_buf);
 472	if (length > 0) {
 473		if (prop_buf[length - 1] == '\n')
 474			prop_buf[length - 1] = 0;
 475		snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf);
 476		envp[env_offset++] = state_buf;
 477	}
 478	envp[env_offset] = NULL;
 479
 480	/* Unlock early before uevent */
 481	spin_unlock_irqrestore(&edev->lock, flags);
 482	kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp);
 483	free_page((unsigned long)prop_buf);
 484
 485	return 0;
 486}
 487EXPORT_SYMBOL_GPL(extcon_sync);
 488
 489/**
 490 * extcon_get_state() - Get the state of an external connector.
 491 * @edev:	the extcon device
 492 * @id:		the unique id indicating an external connector
 493 *
 494 * Returns 0 if success or error number if fail.
 495 */
 496int extcon_get_state(struct extcon_dev *edev, const unsigned int id)
 497{
 498	int index, state;
 499	unsigned long flags;
 500
 501	if (!edev)
 502		return -EINVAL;
 503
 504	index = find_cable_index_by_id(edev, id);
 505	if (index < 0)
 506		return index;
 507
 508	spin_lock_irqsave(&edev->lock, flags);
 509	state = is_extcon_attached(edev, index);
 510	spin_unlock_irqrestore(&edev->lock, flags);
 511
 512	return state;
 513}
 514EXPORT_SYMBOL_GPL(extcon_get_state);
 515
 516/**
 517 * extcon_set_state() - Set the state of an external connector.
 518 * @edev:	the extcon device
 519 * @id:		the unique id indicating an external connector
 520 * @state:	the new state of an external connector.
 521 *		the default semantics is true: attached / false: detached.
 522 *
 523 * Note that this function set the state of an external connector without
 524 * a notification. To synchronize the state of an external connector,
 525 * have to use extcon_set_state_sync() and extcon_sync().
 526 *
 527 * Returns 0 if success or error number if fail.
 528 */
 529int extcon_set_state(struct extcon_dev *edev, unsigned int id, bool state)
 530{
 531	unsigned long flags;
 532	int index, ret = 0;
 533
 534	if (!edev)
 535		return -EINVAL;
 536
 537	index = find_cable_index_by_id(edev, id);
 538	if (index < 0)
 539		return index;
 540
 541	spin_lock_irqsave(&edev->lock, flags);
 542
 543	/* Check whether the external connector's state is changed. */
 544	if (!is_extcon_changed(edev, index, state))
 545		goto out;
 546
 547	if (check_mutually_exclusive(edev,
 548		(edev->state & ~BIT(index)) | (state & BIT(index)))) {
 549		ret = -EPERM;
 550		goto out;
 551	}
 552
 553	/*
 554	 * Initialize the value of extcon property before setting
 555	 * the detached state for an external connector.
 556	 */
 557	if (!state)
 558		init_property(edev, id, index);
 559
 560	/* Update the state for an external connector. */
 561	if (state)
 562		edev->state |= BIT(index);
 563	else
 564		edev->state &= ~(BIT(index));
 565out:
 566	spin_unlock_irqrestore(&edev->lock, flags);
 567
 568	return ret;
 569}
 570EXPORT_SYMBOL_GPL(extcon_set_state);
 571
 572/**
 573 * extcon_set_state_sync() - Set the state of an external connector with sync.
 574 * @edev:	the extcon device
 575 * @id:		the unique id indicating an external connector
 576 * @state:	the new state of external connector.
 577 *		the default semantics is true: attached / false: detached.
 578 *
 579 * Note that this function set the state of external connector
 580 * and synchronize the state by sending a notification.
 581 *
 582 * Returns 0 if success or error number if fail.
 583 */
 584int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id, bool state)
 585{
 586	int ret, index;
 587	unsigned long flags;
 588
 589	index = find_cable_index_by_id(edev, id);
 590	if (index < 0)
 591		return index;
 592
 593	/* Check whether the external connector's state is changed. */
 594	spin_lock_irqsave(&edev->lock, flags);
 595	ret = is_extcon_changed(edev, index, state);
 596	spin_unlock_irqrestore(&edev->lock, flags);
 597	if (!ret)
 598		return 0;
 599
 600	ret = extcon_set_state(edev, id, state);
 601	if (ret < 0)
 602		return ret;
 603
 604	return extcon_sync(edev, id);
 605}
 606EXPORT_SYMBOL_GPL(extcon_set_state_sync);
 607
 608/**
 609 * extcon_get_property() - Get the property value of an external connector.
 610 * @edev:	the extcon device
 611 * @id:		the unique id indicating an external connector
 612 * @prop:	the property id indicating an extcon property
 613 * @prop_val:	the pointer which store the value of extcon property
 614 *
 615 * Note that when getting the property value of external connector,
 616 * the external connector should be attached. If detached state, function
 617 * return 0 without property value. Also, the each property should be
 618 * included in the list of supported properties according to extcon type.
 619 *
 620 * Returns 0 if success or error number if fail.
 621 */
 622int extcon_get_property(struct extcon_dev *edev, unsigned int id,
 623				unsigned int prop,
 624				union extcon_property_value *prop_val)
 625{
 626	struct extcon_cable *cable;
 627	unsigned long flags;
 628	int index, ret = 0;
 629
 630	*prop_val = (union extcon_property_value)(0);
 631
 632	if (!edev)
 633		return -EINVAL;
 634
 635	/* Check whether the property is supported or not */
 636	if (!is_extcon_property_supported(id, prop))
 637		return -EINVAL;
 638
 639	/* Find the cable index of external connector by using id */
 640	index = find_cable_index_by_id(edev, id);
 641	if (index < 0)
 642		return index;
 643
 644	spin_lock_irqsave(&edev->lock, flags);
 645
 646	/* Check whether the property is available or not. */
 647	if (!is_extcon_property_capability(edev, id, index, prop)) {
 648		spin_unlock_irqrestore(&edev->lock, flags);
 649		return -EPERM;
 650	}
 651
 652	/*
 653	 * Check whether the external connector is attached.
 654	 * If external connector is detached, the user can not
 655	 * get the property value.
 656	 */
 657	if (!is_extcon_attached(edev, index)) {
 658		spin_unlock_irqrestore(&edev->lock, flags);
 659		return 0;
 660	}
 661
 662	cable = &edev->cables[index];
 663
 664	/* Get the property value according to extcon type */
 665	switch (prop) {
 666	case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 667		*prop_val = cable->usb_propval[prop - EXTCON_PROP_USB_MIN];
 668		break;
 669	case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 670		*prop_val = cable->chg_propval[prop - EXTCON_PROP_CHG_MIN];
 671		break;
 672	case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 673		*prop_val = cable->jack_propval[prop - EXTCON_PROP_JACK_MIN];
 674		break;
 675	case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 676		*prop_val = cable->disp_propval[prop - EXTCON_PROP_DISP_MIN];
 677		break;
 678	default:
 679		ret = -EINVAL;
 680		break;
 681	}
 682
 683	spin_unlock_irqrestore(&edev->lock, flags);
 684
 685	return ret;
 686}
 687EXPORT_SYMBOL_GPL(extcon_get_property);
 688
 689/**
 690 * extcon_set_property() - Set the property value of an external connector.
 691 * @edev:	the extcon device
 692 * @id:		the unique id indicating an external connector
 693 * @prop:	the property id indicating an extcon property
 694 * @prop_val:	the pointer including the new value of extcon property
 695 *
 696 * Note that each property should be included in the list of supported
 697 * properties according to the extcon type.
 698 *
 699 * Returns 0 if success or error number if fail.
 700 */
 701int extcon_set_property(struct extcon_dev *edev, unsigned int id,
 702				unsigned int prop,
 703				union extcon_property_value prop_val)
 704{
 705	struct extcon_cable *cable;
 706	unsigned long flags;
 707	int index, ret = 0;
 708
 709	if (!edev)
 710		return -EINVAL;
 711
 712	/* Check whether the property is supported or not */
 713	if (!is_extcon_property_supported(id, prop))
 714		return -EINVAL;
 715
 716	/* Find the cable index of external connector by using id */
 717	index = find_cable_index_by_id(edev, id);
 718	if (index < 0)
 719		return index;
 720
 721	spin_lock_irqsave(&edev->lock, flags);
 722
 723	/* Check whether the property is available or not. */
 724	if (!is_extcon_property_capability(edev, id, index, prop)) {
 725		spin_unlock_irqrestore(&edev->lock, flags);
 726		return -EPERM;
 727	}
 728
 729	cable = &edev->cables[index];
 730
 731	/* Set the property value according to extcon type */
 732	switch (prop) {
 733	case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
 734		cable->usb_propval[prop - EXTCON_PROP_USB_MIN] = prop_val;
 735		break;
 736	case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
 737		cable->chg_propval[prop - EXTCON_PROP_CHG_MIN] = prop_val;
 738		break;
 739	case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
 740		cable->jack_propval[prop - EXTCON_PROP_JACK_MIN] = prop_val;
 741		break;
 742	case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
 743		cable->disp_propval[prop - EXTCON_PROP_DISP_MIN] = prop_val;
 744		break;
 745	default:
 746		ret = -EINVAL;
 747		break;
 748	}
 749
 750	spin_unlock_irqrestore(&edev->lock, flags);
 751
 752	return ret;
 753}
 754EXPORT_SYMBOL_GPL(extcon_set_property);
 755
 756/**
 757 * extcon_set_property_sync() - Set property of an external connector with sync.
 758 * @prop_val:	the pointer including the new value of extcon property
 759 *
 760 * Note that when setting the property value of external connector,
 761 * the external connector should be attached. The each property should
 762 * be included in the list of supported properties according to extcon type.
 763 *
 764 * Returns 0 if success or error number if fail.
 765 */
 766int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id,
 767				unsigned int prop,
 768				union extcon_property_value prop_val)
 769{
 770	int ret;
 771
 772	ret = extcon_set_property(edev, id, prop, prop_val);
 773	if (ret < 0)
 774		return ret;
 775
 776	return extcon_sync(edev, id);
 777}
 778EXPORT_SYMBOL_GPL(extcon_set_property_sync);
 779
 780/**
 781 * extcon_get_property_capability() - Get the capability of the property
 782 *					for an external connector.
 783 * @edev:	the extcon device
 784 * @id:		the unique id indicating an external connector
 785 * @prop:	the property id indicating an extcon property
 786 *
 787 * Returns 1 if the property is available or 0 if not available.
 788 */
 789int extcon_get_property_capability(struct extcon_dev *edev, unsigned int id,
 790					unsigned int prop)
 791{
 792	int index;
 793
 794	if (!edev)
 795		return -EINVAL;
 796
 797	/* Check whether the property is supported or not */
 798	if (!is_extcon_property_supported(id, prop))
 799		return -EINVAL;
 800
 801	/* Find the cable index of external connector by using id */
 802	index = find_cable_index_by_id(edev, id);
 803	if (index < 0)
 804		return index;
 805
 806	return is_extcon_property_capability(edev, id, index, prop);
 807}
 808EXPORT_SYMBOL_GPL(extcon_get_property_capability);
 809
 810/**
 811 * extcon_set_property_capability() - Set the capability of the property
 812 *					for an external connector.
 813 * @edev:	the extcon device
 814 * @id:		the unique id indicating an external connector
 815 * @prop:	the property id indicating an extcon property
 816 *
 817 * Note that this function set the capability of the property
 818 * for an external connector in order to mark the bit in capability
 819 * bitmap which mean the available state of the property.
 820 *
 821 * Returns 0 if success or error number if fail.
 822 */
 823int extcon_set_property_capability(struct extcon_dev *edev, unsigned int id,
 824					unsigned int prop)
 825{
 826	struct extcon_cable *cable;
 827	int index, type, ret = 0;
 828
 829	if (!edev)
 830		return -EINVAL;
 831
 832	/* Check whether the property is supported or not. */
 833	if (!is_extcon_property_supported(id, prop))
 834		return -EINVAL;
 835
 836	/* Find the cable index of external connector by using id. */
 837	index = find_cable_index_by_id(edev, id);
 838	if (index < 0)
 839		return index;
 840
 841	type = get_extcon_type(prop);
 842	if (type < 0)
 843		return type;
 844
 845	cable = &edev->cables[index];
 846
 847	switch (type) {
 848	case EXTCON_TYPE_USB:
 849		__set_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
 850		break;
 851	case EXTCON_TYPE_CHG:
 852		__set_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
 853		break;
 854	case EXTCON_TYPE_JACK:
 855		__set_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
 856		break;
 857	case EXTCON_TYPE_DISP:
 858		__set_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
 859		break;
 860	default:
 861		ret = -EINVAL;
 862	}
 863
 864	return ret;
 865}
 866EXPORT_SYMBOL_GPL(extcon_set_property_capability);
 867
 868/**
 869 * extcon_get_extcon_dev() - Get the extcon device instance from the name.
 870 * @extcon_name:	the extcon name provided with extcon_dev_register()
 871 *
 872 * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
 873 */
 874struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
 875{
 876	struct extcon_dev *sd;
 877
 878	if (!extcon_name)
 879		return ERR_PTR(-EINVAL);
 880
 881	mutex_lock(&extcon_dev_list_lock);
 882	list_for_each_entry(sd, &extcon_dev_list, entry) {
 883		if (!strcmp(sd->name, extcon_name))
 884			goto out;
 885	}
 886	sd = NULL;
 887out:
 888	mutex_unlock(&extcon_dev_list_lock);
 889	return sd;
 890}
 891EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
 892
 893/**
 894 * extcon_register_notifier() - Register a notifier block to get notified by
 895 *				any state changes from the extcon.
 896 * @edev:	the extcon device
 897 * @id:		the unique id indicating an external connector
 898 * @nb:		a notifier block to be registered
 899 *
 900 * Note that the second parameter given to the callback of nb (val) is
 901 * the current state of an external connector and the third pameter
 902 * is the pointer of extcon device.
 903 *
 904 * Returns 0 if success or error number if fail.
 905 */
 906int extcon_register_notifier(struct extcon_dev *edev, unsigned int id,
 907			     struct notifier_block *nb)
 908{
 909	unsigned long flags;
 910	int ret, idx = -EINVAL;
 911
 912	if (!edev || !nb)
 913		return -EINVAL;
 914
 915	idx = find_cable_index_by_id(edev, id);
 916	if (idx < 0)
 917		return idx;
 918
 919	spin_lock_irqsave(&edev->lock, flags);
 920	ret = raw_notifier_chain_register(&edev->nh[idx], nb);
 921	spin_unlock_irqrestore(&edev->lock, flags);
 922
 923	return ret;
 924}
 925EXPORT_SYMBOL_GPL(extcon_register_notifier);
 926
 927/**
 928 * extcon_unregister_notifier() - Unregister a notifier block from the extcon.
 929 * @edev:	the extcon device
 930 * @id:		the unique id indicating an external connector
 931 * @nb:		a notifier block to be registered
 932 *
 933 * Returns 0 if success or error number if fail.
 934 */
 935int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id,
 936				struct notifier_block *nb)
 937{
 938	unsigned long flags;
 939	int ret, idx;
 940
 941	if (!edev || !nb)
 942		return -EINVAL;
 943
 944	idx = find_cable_index_by_id(edev, id);
 945	if (idx < 0)
 946		return idx;
 947
 948	spin_lock_irqsave(&edev->lock, flags);
 949	ret = raw_notifier_chain_unregister(&edev->nh[idx], nb);
 950	spin_unlock_irqrestore(&edev->lock, flags);
 951
 952	return ret;
 953}
 954EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
 955
 956/**
 957 * extcon_register_notifier_all() - Register a notifier block for all connectors.
 958 * @edev:	the extcon device
 959 * @nb:		a notifier block to be registered
 960 *
 961 * Note that this function registers a notifier block in order to receive
 962 * the state change of all supported external connectors from extcon device.
 963 * And the second parameter given to the callback of nb (val) is
 964 * the current state and the third pameter is the pointer of extcon device.
 965 *
 966 * Returns 0 if success or error number if fail.
 967 */
 968int extcon_register_notifier_all(struct extcon_dev *edev,
 969				struct notifier_block *nb)
 970{
 971	unsigned long flags;
 972	int ret;
 973
 974	if (!edev || !nb)
 975		return -EINVAL;
 976
 977	spin_lock_irqsave(&edev->lock, flags);
 978	ret = raw_notifier_chain_register(&edev->nh_all, nb);
 979	spin_unlock_irqrestore(&edev->lock, flags);
 980
 981	return ret;
 982}
 983EXPORT_SYMBOL_GPL(extcon_register_notifier_all);
 984
 985/**
 986 * extcon_unregister_notifier_all() - Unregister a notifier block from extcon.
 987 * @edev:	the extcon device
 988 * @nb:		a notifier block to be registered
 989 *
 990 * Returns 0 if success or error number if fail.
 991 */
 992int extcon_unregister_notifier_all(struct extcon_dev *edev,
 993				struct notifier_block *nb)
 994{
 995	unsigned long flags;
 996	int ret;
 997
 998	if (!edev || !nb)
 999		return -EINVAL;
1000
1001	spin_lock_irqsave(&edev->lock, flags);
1002	ret = raw_notifier_chain_unregister(&edev->nh_all, nb);
1003	spin_unlock_irqrestore(&edev->lock, flags);
1004
1005	return ret;
1006}
1007EXPORT_SYMBOL_GPL(extcon_unregister_notifier_all);
1008
1009static struct attribute *extcon_attrs[] = {
1010	&dev_attr_state.attr,
1011	&dev_attr_name.attr,
1012	NULL,
1013};
1014ATTRIBUTE_GROUPS(extcon);
1015
1016static int create_extcon_class(void)
1017{
1018	if (!extcon_class) {
1019		extcon_class = class_create(THIS_MODULE, "extcon");
1020		if (IS_ERR(extcon_class))
1021			return PTR_ERR(extcon_class);
1022		extcon_class->dev_groups = extcon_groups;
1023	}
1024
1025	return 0;
1026}
1027
1028static void extcon_dev_release(struct device *dev)
1029{
1030}
1031
1032static const char *muex_name = "mutually_exclusive";
1033static void dummy_sysfs_dev_release(struct device *dev)
1034{
1035}
1036
1037/*
1038 * extcon_dev_allocate() - Allocate the memory of extcon device.
1039 * @supported_cable:	the array of the supported external connectors
1040 *			ending with EXTCON_NONE.
1041 *
1042 * Note that this function allocates the memory for extcon device 
1043 * and initialize default setting for the extcon device.
1044 *
1045 * Returns the pointer memory of allocated extcon_dev if success
1046 * or ERR_PTR(err) if fail.
1047 */
1048struct extcon_dev *extcon_dev_allocate(const unsigned int *supported_cable)
1049{
1050	struct extcon_dev *edev;
1051
1052	if (!supported_cable)
1053		return ERR_PTR(-EINVAL);
1054
1055	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
1056	if (!edev)
1057		return ERR_PTR(-ENOMEM);
1058
1059	edev->max_supported = 0;
1060	edev->supported_cable = supported_cable;
1061
1062	return edev;
1063}
1064
1065/*
1066 * extcon_dev_free() - Free the memory of extcon device.
1067 * @edev:	the extcon device
1068 */
1069void extcon_dev_free(struct extcon_dev *edev)
1070{
1071	kfree(edev);
1072}
1073EXPORT_SYMBOL_GPL(extcon_dev_free);
1074
1075/**
1076 * extcon_dev_register() - Register an new extcon device
1077 * @edev:	the extcon device to be registered
1078 *
1079 * Among the members of edev struct, please set the "user initializing data"
1080 * do not set the values of "internal data", which are initialized by
1081 * this function.
1082 *
1083 * Note that before calling this funciton, have to allocate the memory
1084 * of an extcon device by using the extcon_dev_allocate(). And the extcon
1085 * dev should include the supported_cable information.
1086 *
1087 * Returns 0 if success or error number if fail.
1088 */
1089int extcon_dev_register(struct extcon_dev *edev)
1090{
1091	int ret, index = 0;
1092	static atomic_t edev_no = ATOMIC_INIT(-1);
1093
1094	if (!extcon_class) {
1095		ret = create_extcon_class();
1096		if (ret < 0)
1097			return ret;
1098	}
1099
1100	if (!edev || !edev->supported_cable)
1101		return -EINVAL;
1102
1103	for (; edev->supported_cable[index] != EXTCON_NONE; index++);
1104
1105	edev->max_supported = index;
1106	if (index > SUPPORTED_CABLE_MAX) {
1107		dev_err(&edev->dev,
1108			"exceed the maximum number of supported cables\n");
1109		return -EINVAL;
1110	}
1111
1112	edev->dev.class = extcon_class;
1113	edev->dev.release = extcon_dev_release;
1114
1115	edev->name = dev_name(edev->dev.parent);
1116	if (IS_ERR_OR_NULL(edev->name)) {
1117		dev_err(&edev->dev,
1118			"extcon device name is null\n");
1119		return -EINVAL;
1120	}
1121	dev_set_name(&edev->dev, "extcon%lu",
1122			(unsigned long)atomic_inc_return(&edev_no));
1123
1124	if (edev->max_supported) {
1125		char buf[10];
1126		char *str;
1127		struct extcon_cable *cable;
1128
1129		edev->cables = kzalloc(sizeof(struct extcon_cable) *
1130				       edev->max_supported, GFP_KERNEL);
1131		if (!edev->cables) {
1132			ret = -ENOMEM;
1133			goto err_sysfs_alloc;
1134		}
1135		for (index = 0; index < edev->max_supported; index++) {
1136			cable = &edev->cables[index];
1137
1138			snprintf(buf, 10, "cable.%d", index);
1139			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
1140				      GFP_KERNEL);
1141			if (!str) {
1142				for (index--; index >= 0; index--) {
1143					cable = &edev->cables[index];
1144					kfree(cable->attr_g.name);
1145				}
1146				ret = -ENOMEM;
1147
1148				goto err_alloc_cables;
1149			}
1150			strcpy(str, buf);
1151
1152			cable->edev = edev;
1153			cable->cable_index = index;
1154			cable->attrs[0] = &cable->attr_name.attr;
1155			cable->attrs[1] = &cable->attr_state.attr;
1156			cable->attrs[2] = NULL;
1157			cable->attr_g.name = str;
1158			cable->attr_g.attrs = cable->attrs;
1159
1160			sysfs_attr_init(&cable->attr_name.attr);
1161			cable->attr_name.attr.name = "name";
1162			cable->attr_name.attr.mode = 0444;
1163			cable->attr_name.show = cable_name_show;
1164
1165			sysfs_attr_init(&cable->attr_state.attr);
1166			cable->attr_state.attr.name = "state";
1167			cable->attr_state.attr.mode = 0444;
1168			cable->attr_state.show = cable_state_show;
1169		}
1170	}
1171
1172	if (edev->max_supported && edev->mutually_exclusive) {
1173		char buf[80];
1174		char *name;
1175
1176		/* Count the size of mutually_exclusive array */
1177		for (index = 0; edev->mutually_exclusive[index]; index++)
1178			;
1179
1180		edev->attrs_muex = kzalloc(sizeof(struct attribute *) *
1181					   (index + 1), GFP_KERNEL);
1182		if (!edev->attrs_muex) {
1183			ret = -ENOMEM;
1184			goto err_muex;
1185		}
1186
1187		edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) *
1188					     index, GFP_KERNEL);
1189		if (!edev->d_attrs_muex) {
1190			ret = -ENOMEM;
1191			kfree(edev->attrs_muex);
1192			goto err_muex;
1193		}
1194
1195		for (index = 0; edev->mutually_exclusive[index]; index++) {
1196			sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
1197			name = kzalloc(sizeof(char) * (strlen(buf) + 1),
1198				       GFP_KERNEL);
1199			if (!name) {
1200				for (index--; index >= 0; index--) {
1201					kfree(edev->d_attrs_muex[index].attr.
1202					      name);
1203				}
1204				kfree(edev->d_attrs_muex);
1205				kfree(edev->attrs_muex);
1206				ret = -ENOMEM;
1207				goto err_muex;
1208			}
1209			strcpy(name, buf);
1210			sysfs_attr_init(&edev->d_attrs_muex[index].attr);
1211			edev->d_attrs_muex[index].attr.name = name;
1212			edev->d_attrs_muex[index].attr.mode = 0000;
1213			edev->attrs_muex[index] = &edev->d_attrs_muex[index]
1214							.attr;
1215		}
1216		edev->attr_g_muex.name = muex_name;
1217		edev->attr_g_muex.attrs = edev->attrs_muex;
1218
1219	}
1220
1221	if (edev->max_supported) {
1222		edev->extcon_dev_type.groups =
1223			kzalloc(sizeof(struct attribute_group *) *
1224				(edev->max_supported + 2), GFP_KERNEL);
1225		if (!edev->extcon_dev_type.groups) {
1226			ret = -ENOMEM;
1227			goto err_alloc_groups;
1228		}
1229
1230		edev->extcon_dev_type.name = dev_name(&edev->dev);
1231		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
1232
1233		for (index = 0; index < edev->max_supported; index++)
1234			edev->extcon_dev_type.groups[index] =
1235				&edev->cables[index].attr_g;
1236		if (edev->mutually_exclusive)
1237			edev->extcon_dev_type.groups[index] =
1238				&edev->attr_g_muex;
1239
1240		edev->dev.type = &edev->extcon_dev_type;
1241	}
1242
1243	ret = device_register(&edev->dev);
1244	if (ret) {
1245		put_device(&edev->dev);
1246		goto err_dev;
1247	}
1248
1249	spin_lock_init(&edev->lock);
1250	edev->nh = devm_kcalloc(&edev->dev, edev->max_supported,
1251				sizeof(*edev->nh), GFP_KERNEL);
1252	if (!edev->nh) {
1253		ret = -ENOMEM;
1254		goto err_dev;
1255	}
1256
1257	for (index = 0; index < edev->max_supported; index++)
1258		RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]);
1259
1260	RAW_INIT_NOTIFIER_HEAD(&edev->nh_all);
1261
1262	dev_set_drvdata(&edev->dev, edev);
1263	edev->state = 0;
1264
1265	mutex_lock(&extcon_dev_list_lock);
1266	list_add(&edev->entry, &extcon_dev_list);
1267	mutex_unlock(&extcon_dev_list_lock);
1268
1269	return 0;
1270
1271err_dev:
1272	if (edev->max_supported)
1273		kfree(edev->extcon_dev_type.groups);
1274err_alloc_groups:
1275	if (edev->max_supported && edev->mutually_exclusive) {
1276		for (index = 0; edev->mutually_exclusive[index]; index++)
1277			kfree(edev->d_attrs_muex[index].attr.name);
1278		kfree(edev->d_attrs_muex);
1279		kfree(edev->attrs_muex);
1280	}
1281err_muex:
1282	for (index = 0; index < edev->max_supported; index++)
1283		kfree(edev->cables[index].attr_g.name);
1284err_alloc_cables:
1285	if (edev->max_supported)
1286		kfree(edev->cables);
1287err_sysfs_alloc:
1288	return ret;
1289}
1290EXPORT_SYMBOL_GPL(extcon_dev_register);
1291
1292/**
1293 * extcon_dev_unregister() - Unregister the extcon device.
1294 * @edev:	the extcon device to be unregistered.
1295 *
1296 * Note that this does not call kfree(edev) because edev was not allocated
1297 * by this class.
1298 */
1299void extcon_dev_unregister(struct extcon_dev *edev)
1300{
1301	int index;
1302
1303	if (!edev)
1304		return;
1305
1306	mutex_lock(&extcon_dev_list_lock);
1307	list_del(&edev->entry);
1308	mutex_unlock(&extcon_dev_list_lock);
1309
1310	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
1311		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
1312				dev_name(&edev->dev));
1313		return;
1314	}
1315
1316	device_unregister(&edev->dev);
1317
1318	if (edev->mutually_exclusive && edev->max_supported) {
1319		for (index = 0; edev->mutually_exclusive[index];
1320				index++)
1321			kfree(edev->d_attrs_muex[index].attr.name);
1322		kfree(edev->d_attrs_muex);
1323		kfree(edev->attrs_muex);
1324	}
1325
1326	for (index = 0; index < edev->max_supported; index++)
1327		kfree(edev->cables[index].attr_g.name);
1328
1329	if (edev->max_supported) {
1330		kfree(edev->extcon_dev_type.groups);
1331		kfree(edev->cables);
1332	}
1333
1334	put_device(&edev->dev);
1335}
1336EXPORT_SYMBOL_GPL(extcon_dev_unregister);
1337
1338#ifdef CONFIG_OF
1339
1340/*
1341 * extcon_find_edev_by_node - Find the extcon device from devicetree.
1342 * @node	: OF node identifying edev
1343 *
1344 * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
1345 */
1346struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1347{
1348	struct extcon_dev *edev;
1349
1350	mutex_lock(&extcon_dev_list_lock);
1351	list_for_each_entry(edev, &extcon_dev_list, entry)
1352		if (edev->dev.parent && edev->dev.parent->of_node == node)
1353			goto out;
1354	edev = ERR_PTR(-EPROBE_DEFER);
1355out:
1356	mutex_unlock(&extcon_dev_list_lock);
1357
1358	return edev;
1359}
1360
1361/*
1362 * extcon_get_edev_by_phandle - Get the extcon device from devicetree.
1363 * @dev		: the instance to the given device
1364 * @index	: the index into list of extcon_dev
1365 *
1366 * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
1367 */
1368struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1369{
1370	struct device_node *node;
1371	struct extcon_dev *edev;
1372
1373	if (!dev)
1374		return ERR_PTR(-EINVAL);
1375
1376	if (!dev->of_node) {
1377		dev_dbg(dev, "device does not have a device node entry\n");
1378		return ERR_PTR(-EINVAL);
1379	}
1380
1381	node = of_parse_phandle(dev->of_node, "extcon", index);
1382	if (!node) {
1383		dev_dbg(dev, "failed to get phandle in %pOF node\n",
1384			dev->of_node);
1385		return ERR_PTR(-ENODEV);
1386	}
1387
1388	edev = extcon_find_edev_by_node(node);
1389	of_node_put(node);
1390
1391	return edev;
1392}
1393
1394#else
1395
1396struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1397{
1398	return ERR_PTR(-ENOSYS);
1399}
1400
1401struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1402{
1403	return ERR_PTR(-ENOSYS);
1404}
1405
1406#endif /* CONFIG_OF */
1407
1408EXPORT_SYMBOL_GPL(extcon_find_edev_by_node);
1409EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
1410
1411/**
1412 * extcon_get_edev_name() - Get the name of the extcon device.
1413 * @edev:	the extcon device
1414 */
1415const char *extcon_get_edev_name(struct extcon_dev *edev)
1416{
1417	return !edev ? NULL : edev->name;
1418}
1419
1420static int __init extcon_class_init(void)
1421{
1422	return create_extcon_class();
1423}
1424module_init(extcon_class_init);
1425
1426static void __exit extcon_class_exit(void)
1427{
1428	class_destroy(extcon_class);
1429}
1430module_exit(extcon_class_exit);
1431
1432MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
1433MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1434MODULE_DESCRIPTION("External Connector (extcon) framework");
1435MODULE_LICENSE("GPL v2");