xref: /linux/drivers/extcon/extcon.c (revision 122333d6bd229af279cdb35d1b874b71b3b9ccfb)
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 	[EXTCON_DISP_CVBS] = {
171 		.type = EXTCON_TYPE_DISP,
172 		.id = EXTCON_DISP_CVBS,
173 		.name = "CVBS",
174 	},
175 	[EXTCON_DISP_EDP] = {
176 		.type = EXTCON_TYPE_DISP,
177 		.id = EXTCON_DISP_EDP,
178 		.name = "EDP",
179 	},
180 
181 	/* Miscellaneous external connector */
182 	[EXTCON_DOCK] = {
183 		.type = EXTCON_TYPE_MISC,
184 		.id = EXTCON_DOCK,
185 		.name = "DOCK",
186 	},
187 	[EXTCON_JIG] = {
188 		.type = EXTCON_TYPE_MISC,
189 		.id = EXTCON_JIG,
190 		.name = "JIG",
191 	},
192 	[EXTCON_MECHANICAL] = {
193 		.type = EXTCON_TYPE_MISC,
194 		.id = EXTCON_MECHANICAL,
195 		.name = "MECHANICAL",
196 	},
197 
198 	{ /* sentinel */ }
199 };
200 
201 /**
202  * struct extcon_cable - An internal data for an external connector.
203  * @edev:		the extcon device
204  * @cable_index:	the index of this cable in the edev
205  * @attr_g:		the attribute group for the cable
206  * @attr_name:		"name" sysfs entry
207  * @attr_state:		"state" sysfs entry
208  * @attrs:		the array pointing to attr_name and attr_state for attr_g
209  */
210 struct extcon_cable {
211 	struct extcon_dev *edev;
212 	int cable_index;
213 
214 	struct attribute_group attr_g;
215 	struct device_attribute attr_name;
216 	struct device_attribute attr_state;
217 
218 	struct attribute *attrs[3]; /* to be fed to attr_g.attrs */
219 
220 	union extcon_property_value usb_propval[EXTCON_PROP_USB_CNT];
221 	union extcon_property_value chg_propval[EXTCON_PROP_CHG_CNT];
222 	union extcon_property_value jack_propval[EXTCON_PROP_JACK_CNT];
223 	union extcon_property_value disp_propval[EXTCON_PROP_DISP_CNT];
224 
225 	unsigned long usb_bits[BITS_TO_LONGS(EXTCON_PROP_USB_CNT)];
226 	unsigned long chg_bits[BITS_TO_LONGS(EXTCON_PROP_CHG_CNT)];
227 	unsigned long jack_bits[BITS_TO_LONGS(EXTCON_PROP_JACK_CNT)];
228 	unsigned long disp_bits[BITS_TO_LONGS(EXTCON_PROP_DISP_CNT)];
229 };
230 
231 static struct class *extcon_class;
232 
233 static LIST_HEAD(extcon_dev_list);
234 static DEFINE_MUTEX(extcon_dev_list_lock);
235 
236 static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
237 {
238 	int i = 0;
239 
240 	if (!edev->mutually_exclusive)
241 		return 0;
242 
243 	for (i = 0; edev->mutually_exclusive[i]; i++) {
244 		int weight;
245 		u32 correspondants = new_state & edev->mutually_exclusive[i];
246 
247 		/* calculate the total number of bits set */
248 		weight = hweight32(correspondants);
249 		if (weight > 1)
250 			return i + 1;
251 	}
252 
253 	return 0;
254 }
255 
256 static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id)
257 {
258 	int i;
259 
260 	/* Find the index of extcon cable in edev->supported_cable */
261 	for (i = 0; i < edev->max_supported; i++) {
262 		if (edev->supported_cable[i] == id)
263 			return i;
264 	}
265 
266 	return -EINVAL;
267 }
268 
269 static int get_extcon_type(unsigned int prop)
270 {
271 	switch (prop) {
272 	case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
273 		return EXTCON_TYPE_USB;
274 	case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
275 		return EXTCON_TYPE_CHG;
276 	case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
277 		return EXTCON_TYPE_JACK;
278 	case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
279 		return EXTCON_TYPE_DISP;
280 	default:
281 		return -EINVAL;
282 	}
283 }
284 
285 static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index)
286 {
287 	return !!(edev->state & BIT(index));
288 }
289 
290 static bool is_extcon_changed(struct extcon_dev *edev, int index,
291 				bool new_state)
292 {
293 	int state = !!(edev->state & BIT(index));
294 	return (state != new_state);
295 }
296 
297 static bool is_extcon_property_supported(unsigned int id, unsigned int prop)
298 {
299 	int type;
300 
301 	/* Check whether the property is supported or not. */
302 	type = get_extcon_type(prop);
303 	if (type < 0)
304 		return false;
305 
306 	/* Check whether a specific extcon id supports the property or not. */
307 	return !!(extcon_info[id].type & type);
308 }
309 
310 static int is_extcon_property_capability(struct extcon_dev *edev,
311 				unsigned int id, int index,unsigned int prop)
312 {
313 	struct extcon_cable *cable;
314 	int type, ret;
315 
316 	/* Check whether the property is supported or not. */
317 	type = get_extcon_type(prop);
318 	if (type < 0)
319 		return type;
320 
321 	cable = &edev->cables[index];
322 
323 	switch (type) {
324 	case EXTCON_TYPE_USB:
325 		ret = test_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
326 		break;
327 	case EXTCON_TYPE_CHG:
328 		ret = test_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
329 		break;
330 	case EXTCON_TYPE_JACK:
331 		ret = test_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
332 		break;
333 	case EXTCON_TYPE_DISP:
334 		ret = test_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
335 		break;
336 	default:
337 		ret = -EINVAL;
338 	}
339 
340 	return ret;
341 }
342 
343 static void init_property(struct extcon_dev *edev, unsigned int id, int index)
344 {
345 	unsigned int type = extcon_info[id].type;
346 	struct extcon_cable *cable = &edev->cables[index];
347 
348 	if (EXTCON_TYPE_USB & type)
349 		memset(cable->usb_propval, 0, sizeof(cable->usb_propval));
350 	if (EXTCON_TYPE_CHG & type)
351 		memset(cable->chg_propval, 0, sizeof(cable->chg_propval));
352 	if (EXTCON_TYPE_JACK & type)
353 		memset(cable->jack_propval, 0, sizeof(cable->jack_propval));
354 	if (EXTCON_TYPE_DISP & type)
355 		memset(cable->disp_propval, 0, sizeof(cable->disp_propval));
356 }
357 
358 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
359 			  char *buf)
360 {
361 	int i, count = 0;
362 	struct extcon_dev *edev = dev_get_drvdata(dev);
363 
364 	if (edev->max_supported == 0)
365 		return sprintf(buf, "%u\n", edev->state);
366 
367 	for (i = 0; i < edev->max_supported; i++) {
368 		count += sprintf(buf + count, "%s=%d\n",
369 				extcon_info[edev->supported_cable[i]].name,
370 				 !!(edev->state & BIT(i)));
371 	}
372 
373 	return count;
374 }
375 static DEVICE_ATTR_RO(state);
376 
377 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
378 		char *buf)
379 {
380 	struct extcon_dev *edev = dev_get_drvdata(dev);
381 
382 	return sprintf(buf, "%s\n", edev->name);
383 }
384 static DEVICE_ATTR_RO(name);
385 
386 static ssize_t cable_name_show(struct device *dev,
387 			       struct device_attribute *attr, char *buf)
388 {
389 	struct extcon_cable *cable = container_of(attr, struct extcon_cable,
390 						  attr_name);
391 	int i = cable->cable_index;
392 
393 	return sprintf(buf, "%s\n",
394 			extcon_info[cable->edev->supported_cable[i]].name);
395 }
396 
397 static ssize_t cable_state_show(struct device *dev,
398 				struct device_attribute *attr, char *buf)
399 {
400 	struct extcon_cable *cable = container_of(attr, struct extcon_cable,
401 						  attr_state);
402 
403 	int i = cable->cable_index;
404 
405 	return sprintf(buf, "%d\n",
406 		extcon_get_state(cable->edev, cable->edev->supported_cable[i]));
407 }
408 
409 /**
410  * extcon_sync() - Synchronize the state for an external connector.
411  * @edev:	the extcon device
412  * @id:		the unique id indicating an external connector
413  *
414  * Note that this function send a notification in order to synchronize
415  * the state and property of an external connector.
416  *
417  * Returns 0 if success or error number if fail.
418  */
419 int extcon_sync(struct extcon_dev *edev, unsigned int id)
420 {
421 	char name_buf[120];
422 	char state_buf[120];
423 	char *prop_buf;
424 	char *envp[3];
425 	int env_offset = 0;
426 	int length;
427 	int index;
428 	int state;
429 	unsigned long flags;
430 
431 	if (!edev)
432 		return -EINVAL;
433 
434 	index = find_cable_index_by_id(edev, id);
435 	if (index < 0)
436 		return index;
437 
438 	spin_lock_irqsave(&edev->lock, flags);
439 	state = !!(edev->state & BIT(index));
440 	spin_unlock_irqrestore(&edev->lock, flags);
441 
442 	/*
443 	 * Call functions in a raw notifier chain for the specific one
444 	 * external connector.
445 	 */
446 	raw_notifier_call_chain(&edev->nh[index], state, edev);
447 
448 	/*
449 	 * Call functions in a raw notifier chain for the all supported
450 	 * external connectors.
451 	 */
452 	raw_notifier_call_chain(&edev->nh_all, state, edev);
453 
454 	spin_lock_irqsave(&edev->lock, flags);
455 	/* This could be in interrupt handler */
456 	prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
457 	if (!prop_buf) {
458 		/* Unlock early before uevent */
459 		spin_unlock_irqrestore(&edev->lock, flags);
460 
461 		dev_err(&edev->dev, "out of memory in extcon_set_state\n");
462 		kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE);
463 
464 		return -ENOMEM;
465 	}
466 
467 	length = name_show(&edev->dev, NULL, prop_buf);
468 	if (length > 0) {
469 		if (prop_buf[length - 1] == '\n')
470 			prop_buf[length - 1] = 0;
471 		snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf);
472 		envp[env_offset++] = name_buf;
473 	}
474 
475 	length = state_show(&edev->dev, NULL, prop_buf);
476 	if (length > 0) {
477 		if (prop_buf[length - 1] == '\n')
478 			prop_buf[length - 1] = 0;
479 		snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf);
480 		envp[env_offset++] = state_buf;
481 	}
482 	envp[env_offset] = NULL;
483 
484 	/* Unlock early before uevent */
485 	spin_unlock_irqrestore(&edev->lock, flags);
486 	kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp);
487 	free_page((unsigned long)prop_buf);
488 
489 	return 0;
490 }
491 EXPORT_SYMBOL_GPL(extcon_sync);
492 
493 /**
494  * extcon_get_state() - Get the state of an external connector.
495  * @edev:	the extcon device
496  * @id:		the unique id indicating an external connector
497  *
498  * Returns 0 if success or error number if fail.
499  */
500 int extcon_get_state(struct extcon_dev *edev, const unsigned int id)
501 {
502 	int index, state;
503 	unsigned long flags;
504 
505 	if (!edev)
506 		return -EINVAL;
507 
508 	index = find_cable_index_by_id(edev, id);
509 	if (index < 0)
510 		return index;
511 
512 	spin_lock_irqsave(&edev->lock, flags);
513 	state = is_extcon_attached(edev, index);
514 	spin_unlock_irqrestore(&edev->lock, flags);
515 
516 	return state;
517 }
518 EXPORT_SYMBOL_GPL(extcon_get_state);
519 
520 /**
521  * extcon_set_state() - Set the state of an external connector.
522  * @edev:	the extcon device
523  * @id:		the unique id indicating an external connector
524  * @state:	the new state of an external connector.
525  *		the default semantics is true: attached / false: detached.
526  *
527  * Note that this function set the state of an external connector without
528  * a notification. To synchronize the state of an external connector,
529  * have to use extcon_set_state_sync() and extcon_sync().
530  *
531  * Returns 0 if success or error number if fail.
532  */
533 int extcon_set_state(struct extcon_dev *edev, unsigned int id, bool state)
534 {
535 	unsigned long flags;
536 	int index, ret = 0;
537 
538 	if (!edev)
539 		return -EINVAL;
540 
541 	index = find_cable_index_by_id(edev, id);
542 	if (index < 0)
543 		return index;
544 
545 	spin_lock_irqsave(&edev->lock, flags);
546 
547 	/* Check whether the external connector's state is changed. */
548 	if (!is_extcon_changed(edev, index, state))
549 		goto out;
550 
551 	if (check_mutually_exclusive(edev,
552 		(edev->state & ~BIT(index)) | (state & BIT(index)))) {
553 		ret = -EPERM;
554 		goto out;
555 	}
556 
557 	/*
558 	 * Initialize the value of extcon property before setting
559 	 * the detached state for an external connector.
560 	 */
561 	if (!state)
562 		init_property(edev, id, index);
563 
564 	/* Update the state for an external connector. */
565 	if (state)
566 		edev->state |= BIT(index);
567 	else
568 		edev->state &= ~(BIT(index));
569 out:
570 	spin_unlock_irqrestore(&edev->lock, flags);
571 
572 	return ret;
573 }
574 EXPORT_SYMBOL_GPL(extcon_set_state);
575 
576 /**
577  * extcon_set_state_sync() - Set the state of an external connector with sync.
578  * @edev:	the extcon device
579  * @id:		the unique id indicating an external connector
580  * @state:	the new state of external connector.
581  *		the default semantics is true: attached / false: detached.
582  *
583  * Note that this function set the state of external connector
584  * and synchronize the state by sending a notification.
585  *
586  * Returns 0 if success or error number if fail.
587  */
588 int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id, bool state)
589 {
590 	int ret;
591 
592 	ret = extcon_set_state(edev, id, state);
593 	if (ret < 0)
594 		return ret;
595 
596 	return extcon_sync(edev, id);
597 }
598 EXPORT_SYMBOL_GPL(extcon_set_state_sync);
599 
600 /**
601  * extcon_get_property() - Get the property value of an external connector.
602  * @edev:	the extcon device
603  * @id:		the unique id indicating an external connector
604  * @prop:	the property id indicating an extcon property
605  * @prop_val:	the pointer which store the value of extcon property
606  *
607  * Note that when getting the property value of external connector,
608  * the external connector should be attached. If detached state, function
609  * return 0 without property value. Also, the each property should be
610  * included in the list of supported properties according to extcon type.
611  *
612  * Returns 0 if success or error number if fail.
613  */
614 int extcon_get_property(struct extcon_dev *edev, unsigned int id,
615 				unsigned int prop,
616 				union extcon_property_value *prop_val)
617 {
618 	struct extcon_cable *cable;
619 	unsigned long flags;
620 	int index, ret = 0;
621 
622 	*prop_val = (union extcon_property_value){0};
623 
624 	if (!edev)
625 		return -EINVAL;
626 
627 	/* Check whether the property is supported or not */
628 	if (!is_extcon_property_supported(id, prop))
629 		return -EINVAL;
630 
631 	/* Find the cable index of external connector by using id */
632 	index = find_cable_index_by_id(edev, id);
633 	if (index < 0)
634 		return index;
635 
636 	spin_lock_irqsave(&edev->lock, flags);
637 
638 	/* Check whether the property is available or not. */
639 	if (!is_extcon_property_capability(edev, id, index, prop)) {
640 		spin_unlock_irqrestore(&edev->lock, flags);
641 		return -EPERM;
642 	}
643 
644 	/*
645 	 * Check whether the external connector is attached.
646 	 * If external connector is detached, the user can not
647 	 * get the property value.
648 	 */
649 	if (!is_extcon_attached(edev, index)) {
650 		spin_unlock_irqrestore(&edev->lock, flags);
651 		return 0;
652 	}
653 
654 	cable = &edev->cables[index];
655 
656 	/* Get the property value according to extcon type */
657 	switch (prop) {
658 	case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
659 		*prop_val = cable->usb_propval[prop - EXTCON_PROP_USB_MIN];
660 		break;
661 	case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
662 		*prop_val = cable->chg_propval[prop - EXTCON_PROP_CHG_MIN];
663 		break;
664 	case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
665 		*prop_val = cable->jack_propval[prop - EXTCON_PROP_JACK_MIN];
666 		break;
667 	case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
668 		*prop_val = cable->disp_propval[prop - EXTCON_PROP_DISP_MIN];
669 		break;
670 	default:
671 		ret = -EINVAL;
672 		break;
673 	}
674 
675 	spin_unlock_irqrestore(&edev->lock, flags);
676 
677 	return ret;
678 }
679 EXPORT_SYMBOL_GPL(extcon_get_property);
680 
681 /**
682  * extcon_set_property() - Set the property value of an external connector.
683  * @edev:	the extcon device
684  * @id:		the unique id indicating an external connector
685  * @prop:	the property id indicating an extcon property
686  * @prop_val:	the pointer including the new value of extcon property
687  *
688  * Note that each property should be included in the list of supported
689  * properties according to the extcon type.
690  *
691  * Returns 0 if success or error number if fail.
692  */
693 int extcon_set_property(struct extcon_dev *edev, unsigned int id,
694 				unsigned int prop,
695 				union extcon_property_value prop_val)
696 {
697 	struct extcon_cable *cable;
698 	unsigned long flags;
699 	int index, ret = 0;
700 
701 	if (!edev)
702 		return -EINVAL;
703 
704 	/* Check whether the property is supported or not */
705 	if (!is_extcon_property_supported(id, prop))
706 		return -EINVAL;
707 
708 	/* Find the cable index of external connector by using id */
709 	index = find_cable_index_by_id(edev, id);
710 	if (index < 0)
711 		return index;
712 
713 	spin_lock_irqsave(&edev->lock, flags);
714 
715 	/* Check whether the property is available or not. */
716 	if (!is_extcon_property_capability(edev, id, index, prop)) {
717 		spin_unlock_irqrestore(&edev->lock, flags);
718 		return -EPERM;
719 	}
720 
721 	cable = &edev->cables[index];
722 
723 	/* Set the property value according to extcon type */
724 	switch (prop) {
725 	case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
726 		cable->usb_propval[prop - EXTCON_PROP_USB_MIN] = prop_val;
727 		break;
728 	case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
729 		cable->chg_propval[prop - EXTCON_PROP_CHG_MIN] = prop_val;
730 		break;
731 	case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
732 		cable->jack_propval[prop - EXTCON_PROP_JACK_MIN] = prop_val;
733 		break;
734 	case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
735 		cable->disp_propval[prop - EXTCON_PROP_DISP_MIN] = prop_val;
736 		break;
737 	default:
738 		ret = -EINVAL;
739 		break;
740 	}
741 
742 	spin_unlock_irqrestore(&edev->lock, flags);
743 
744 	return ret;
745 }
746 EXPORT_SYMBOL_GPL(extcon_set_property);
747 
748 /**
749  * extcon_set_property_sync() - Set property of an external connector with sync.
750  * @edev:	the extcon device
751  * @id:		the unique id indicating an external connector
752  * @prop:	the property id indicating an extcon property
753  * @prop_val:	the pointer including the new value of extcon property
754  *
755  * Note that when setting the property value of external connector,
756  * the external connector should be attached. The each property should
757  * be included in the list of supported properties according to extcon type.
758  *
759  * Returns 0 if success or error number if fail.
760  */
761 int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id,
762 				unsigned int prop,
763 				union extcon_property_value prop_val)
764 {
765 	int ret;
766 
767 	ret = extcon_set_property(edev, id, prop, prop_val);
768 	if (ret < 0)
769 		return ret;
770 
771 	return extcon_sync(edev, id);
772 }
773 EXPORT_SYMBOL_GPL(extcon_set_property_sync);
774 
775 /**
776  * extcon_get_property_capability() - Get the capability of the property
777  *					for an external connector.
778  * @edev:	the extcon device
779  * @id:		the unique id indicating an external connector
780  * @prop:	the property id indicating an extcon property
781  *
782  * Returns 1 if the property is available or 0 if not available.
783  */
784 int extcon_get_property_capability(struct extcon_dev *edev, unsigned int id,
785 					unsigned int prop)
786 {
787 	int index;
788 
789 	if (!edev)
790 		return -EINVAL;
791 
792 	/* Check whether the property is supported or not */
793 	if (!is_extcon_property_supported(id, prop))
794 		return -EINVAL;
795 
796 	/* Find the cable index of external connector by using id */
797 	index = find_cable_index_by_id(edev, id);
798 	if (index < 0)
799 		return index;
800 
801 	return is_extcon_property_capability(edev, id, index, prop);
802 }
803 EXPORT_SYMBOL_GPL(extcon_get_property_capability);
804 
805 /**
806  * extcon_set_property_capability() - Set the capability of the property
807  *					for an external connector.
808  * @edev:	the extcon device
809  * @id:		the unique id indicating an external connector
810  * @prop:	the property id indicating an extcon property
811  *
812  * Note that this function set the capability of the property
813  * for an external connector in order to mark the bit in capability
814  * bitmap which mean the available state of the property.
815  *
816  * Returns 0 if success or error number if fail.
817  */
818 int extcon_set_property_capability(struct extcon_dev *edev, unsigned int id,
819 					unsigned int prop)
820 {
821 	struct extcon_cable *cable;
822 	int index, type, ret = 0;
823 
824 	if (!edev)
825 		return -EINVAL;
826 
827 	/* Check whether the property is supported or not. */
828 	if (!is_extcon_property_supported(id, prop))
829 		return -EINVAL;
830 
831 	/* Find the cable index of external connector by using id. */
832 	index = find_cable_index_by_id(edev, id);
833 	if (index < 0)
834 		return index;
835 
836 	type = get_extcon_type(prop);
837 	if (type < 0)
838 		return type;
839 
840 	cable = &edev->cables[index];
841 
842 	switch (type) {
843 	case EXTCON_TYPE_USB:
844 		__set_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
845 		break;
846 	case EXTCON_TYPE_CHG:
847 		__set_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
848 		break;
849 	case EXTCON_TYPE_JACK:
850 		__set_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
851 		break;
852 	case EXTCON_TYPE_DISP:
853 		__set_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
854 		break;
855 	default:
856 		ret = -EINVAL;
857 	}
858 
859 	return ret;
860 }
861 EXPORT_SYMBOL_GPL(extcon_set_property_capability);
862 
863 /**
864  * extcon_get_extcon_dev() - Get the extcon device instance from the name.
865  * @extcon_name:	the extcon name provided with extcon_dev_register()
866  *
867  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
868  * NOTE: This function returns -EPROBE_DEFER so it may only be called from
869  * probe() functions.
870  */
871 struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
872 {
873 	struct extcon_dev *sd;
874 
875 	if (!extcon_name)
876 		return ERR_PTR(-EINVAL);
877 
878 	mutex_lock(&extcon_dev_list_lock);
879 	list_for_each_entry(sd, &extcon_dev_list, entry) {
880 		if (!strcmp(sd->name, extcon_name))
881 			goto out;
882 	}
883 	sd = ERR_PTR(-EPROBE_DEFER);
884 out:
885 	mutex_unlock(&extcon_dev_list_lock);
886 	return sd;
887 }
888 EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
889 
890 /**
891  * extcon_register_notifier() - Register a notifier block to get notified by
892  *				any state changes from the extcon.
893  * @edev:	the extcon device
894  * @id:		the unique id indicating an external connector
895  * @nb:		a notifier block to be registered
896  *
897  * Note that the second parameter given to the callback of nb (val) is
898  * the current state of an external connector and the third pameter
899  * is the pointer of extcon device.
900  *
901  * Returns 0 if success or error number if fail.
902  */
903 int extcon_register_notifier(struct extcon_dev *edev, unsigned int id,
904 			     struct notifier_block *nb)
905 {
906 	unsigned long flags;
907 	int ret, idx;
908 
909 	if (!edev || !nb)
910 		return -EINVAL;
911 
912 	idx = find_cable_index_by_id(edev, id);
913 	if (idx < 0)
914 		return idx;
915 
916 	spin_lock_irqsave(&edev->lock, flags);
917 	ret = raw_notifier_chain_register(&edev->nh[idx], nb);
918 	spin_unlock_irqrestore(&edev->lock, flags);
919 
920 	return ret;
921 }
922 EXPORT_SYMBOL_GPL(extcon_register_notifier);
923 
924 /**
925  * extcon_unregister_notifier() - Unregister a notifier block from the extcon.
926  * @edev:	the extcon device
927  * @id:		the unique id indicating an external connector
928  * @nb:		a notifier block to be registered
929  *
930  * Returns 0 if success or error number if fail.
931  */
932 int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id,
933 				struct notifier_block *nb)
934 {
935 	unsigned long flags;
936 	int ret, idx;
937 
938 	if (!edev || !nb)
939 		return -EINVAL;
940 
941 	idx = find_cable_index_by_id(edev, id);
942 	if (idx < 0)
943 		return idx;
944 
945 	spin_lock_irqsave(&edev->lock, flags);
946 	ret = raw_notifier_chain_unregister(&edev->nh[idx], nb);
947 	spin_unlock_irqrestore(&edev->lock, flags);
948 
949 	return ret;
950 }
951 EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
952 
953 /**
954  * extcon_register_notifier_all() - Register a notifier block for all connectors.
955  * @edev:	the extcon device
956  * @nb:		a notifier block to be registered
957  *
958  * Note that this function registers a notifier block in order to receive
959  * the state change of all supported external connectors from extcon device.
960  * And the second parameter given to the callback of nb (val) is
961  * the current state and the third pameter is the pointer of extcon device.
962  *
963  * Returns 0 if success or error number if fail.
964  */
965 int extcon_register_notifier_all(struct extcon_dev *edev,
966 				struct notifier_block *nb)
967 {
968 	unsigned long flags;
969 	int ret;
970 
971 	if (!edev || !nb)
972 		return -EINVAL;
973 
974 	spin_lock_irqsave(&edev->lock, flags);
975 	ret = raw_notifier_chain_register(&edev->nh_all, nb);
976 	spin_unlock_irqrestore(&edev->lock, flags);
977 
978 	return ret;
979 }
980 EXPORT_SYMBOL_GPL(extcon_register_notifier_all);
981 
982 /**
983  * extcon_unregister_notifier_all() - Unregister a notifier block from extcon.
984  * @edev:	the extcon device
985  * @nb:		a notifier block to be registered
986  *
987  * Returns 0 if success or error number if fail.
988  */
989 int extcon_unregister_notifier_all(struct extcon_dev *edev,
990 				struct notifier_block *nb)
991 {
992 	unsigned long flags;
993 	int ret;
994 
995 	if (!edev || !nb)
996 		return -EINVAL;
997 
998 	spin_lock_irqsave(&edev->lock, flags);
999 	ret = raw_notifier_chain_unregister(&edev->nh_all, nb);
1000 	spin_unlock_irqrestore(&edev->lock, flags);
1001 
1002 	return ret;
1003 }
1004 EXPORT_SYMBOL_GPL(extcon_unregister_notifier_all);
1005 
1006 static struct attribute *extcon_attrs[] = {
1007 	&dev_attr_state.attr,
1008 	&dev_attr_name.attr,
1009 	NULL,
1010 };
1011 ATTRIBUTE_GROUPS(extcon);
1012 
1013 static int create_extcon_class(void)
1014 {
1015 	if (!extcon_class) {
1016 		extcon_class = class_create("extcon");
1017 		if (IS_ERR(extcon_class))
1018 			return PTR_ERR(extcon_class);
1019 		extcon_class->dev_groups = extcon_groups;
1020 	}
1021 
1022 	return 0;
1023 }
1024 
1025 static void extcon_dev_release(struct device *dev)
1026 {
1027 }
1028 
1029 static const char *muex_name = "mutually_exclusive";
1030 static void dummy_sysfs_dev_release(struct device *dev)
1031 {
1032 }
1033 
1034 /*
1035  * extcon_dev_allocate() - Allocate the memory of extcon device.
1036  * @supported_cable:	the array of the supported external connectors
1037  *			ending with EXTCON_NONE.
1038  *
1039  * Note that this function allocates the memory for extcon device
1040  * and initialize default setting for the extcon device.
1041  *
1042  * Returns the pointer memory of allocated extcon_dev if success
1043  * or ERR_PTR(err) if fail.
1044  */
1045 struct extcon_dev *extcon_dev_allocate(const unsigned int *supported_cable)
1046 {
1047 	struct extcon_dev *edev;
1048 
1049 	if (!supported_cable)
1050 		return ERR_PTR(-EINVAL);
1051 
1052 	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
1053 	if (!edev)
1054 		return ERR_PTR(-ENOMEM);
1055 
1056 	edev->max_supported = 0;
1057 	edev->supported_cable = supported_cable;
1058 
1059 	return edev;
1060 }
1061 
1062 /*
1063  * extcon_dev_free() - Free the memory of extcon device.
1064  * @edev:	the extcon device
1065  */
1066 void extcon_dev_free(struct extcon_dev *edev)
1067 {
1068 	kfree(edev);
1069 }
1070 EXPORT_SYMBOL_GPL(extcon_dev_free);
1071 
1072 /**
1073  * extcon_dev_register() - Register an new extcon device
1074  * @edev:	the extcon device to be registered
1075  *
1076  * Among the members of edev struct, please set the "user initializing data"
1077  * do not set the values of "internal data", which are initialized by
1078  * this function.
1079  *
1080  * Note that before calling this funciton, have to allocate the memory
1081  * of an extcon device by using the extcon_dev_allocate(). And the extcon
1082  * dev should include the supported_cable information.
1083  *
1084  * Returns 0 if success or error number if fail.
1085  */
1086 int extcon_dev_register(struct extcon_dev *edev)
1087 {
1088 	int ret, index = 0;
1089 	static atomic_t edev_no = ATOMIC_INIT(-1);
1090 
1091 	if (!extcon_class) {
1092 		ret = create_extcon_class();
1093 		if (ret < 0)
1094 			return ret;
1095 	}
1096 
1097 	if (!edev || !edev->supported_cable)
1098 		return -EINVAL;
1099 
1100 	for (; edev->supported_cable[index] != EXTCON_NONE; index++);
1101 
1102 	edev->max_supported = index;
1103 	if (index > SUPPORTED_CABLE_MAX) {
1104 		dev_err(&edev->dev,
1105 			"exceed the maximum number of supported cables\n");
1106 		return -EINVAL;
1107 	}
1108 
1109 	edev->dev.class = extcon_class;
1110 	edev->dev.release = extcon_dev_release;
1111 
1112 	edev->name = dev_name(edev->dev.parent);
1113 	if (IS_ERR_OR_NULL(edev->name)) {
1114 		dev_err(&edev->dev,
1115 			"extcon device name is null\n");
1116 		return -EINVAL;
1117 	}
1118 	dev_set_name(&edev->dev, "extcon%lu",
1119 			(unsigned long)atomic_inc_return(&edev_no));
1120 
1121 	if (edev->max_supported) {
1122 		char *str;
1123 		struct extcon_cable *cable;
1124 
1125 		edev->cables = kcalloc(edev->max_supported,
1126 				       sizeof(struct extcon_cable),
1127 				       GFP_KERNEL);
1128 		if (!edev->cables) {
1129 			ret = -ENOMEM;
1130 			goto err_sysfs_alloc;
1131 		}
1132 		for (index = 0; index < edev->max_supported; index++) {
1133 			cable = &edev->cables[index];
1134 
1135 			str = kasprintf(GFP_KERNEL, "cable.%d", index);
1136 			if (!str) {
1137 				for (index--; index >= 0; index--) {
1138 					cable = &edev->cables[index];
1139 					kfree(cable->attr_g.name);
1140 				}
1141 				ret = -ENOMEM;
1142 
1143 				goto err_alloc_cables;
1144 			}
1145 
1146 			cable->edev = edev;
1147 			cable->cable_index = index;
1148 			cable->attrs[0] = &cable->attr_name.attr;
1149 			cable->attrs[1] = &cable->attr_state.attr;
1150 			cable->attrs[2] = NULL;
1151 			cable->attr_g.name = str;
1152 			cable->attr_g.attrs = cable->attrs;
1153 
1154 			sysfs_attr_init(&cable->attr_name.attr);
1155 			cable->attr_name.attr.name = "name";
1156 			cable->attr_name.attr.mode = 0444;
1157 			cable->attr_name.show = cable_name_show;
1158 
1159 			sysfs_attr_init(&cable->attr_state.attr);
1160 			cable->attr_state.attr.name = "state";
1161 			cable->attr_state.attr.mode = 0444;
1162 			cable->attr_state.show = cable_state_show;
1163 		}
1164 	}
1165 
1166 	if (edev->max_supported && edev->mutually_exclusive) {
1167 		char *name;
1168 
1169 		/* Count the size of mutually_exclusive array */
1170 		for (index = 0; edev->mutually_exclusive[index]; index++)
1171 			;
1172 
1173 		edev->attrs_muex = kcalloc(index + 1,
1174 					   sizeof(struct attribute *),
1175 					   GFP_KERNEL);
1176 		if (!edev->attrs_muex) {
1177 			ret = -ENOMEM;
1178 			goto err_muex;
1179 		}
1180 
1181 		edev->d_attrs_muex = kcalloc(index,
1182 					     sizeof(struct device_attribute),
1183 					     GFP_KERNEL);
1184 		if (!edev->d_attrs_muex) {
1185 			ret = -ENOMEM;
1186 			kfree(edev->attrs_muex);
1187 			goto err_muex;
1188 		}
1189 
1190 		for (index = 0; edev->mutually_exclusive[index]; index++) {
1191 			name = kasprintf(GFP_KERNEL, "0x%x",
1192 					 edev->mutually_exclusive[index]);
1193 			if (!name) {
1194 				for (index--; index >= 0; index--) {
1195 					kfree(edev->d_attrs_muex[index].attr.
1196 					      name);
1197 				}
1198 				kfree(edev->d_attrs_muex);
1199 				kfree(edev->attrs_muex);
1200 				ret = -ENOMEM;
1201 				goto err_muex;
1202 			}
1203 			sysfs_attr_init(&edev->d_attrs_muex[index].attr);
1204 			edev->d_attrs_muex[index].attr.name = name;
1205 			edev->d_attrs_muex[index].attr.mode = 0000;
1206 			edev->attrs_muex[index] = &edev->d_attrs_muex[index]
1207 							.attr;
1208 		}
1209 		edev->attr_g_muex.name = muex_name;
1210 		edev->attr_g_muex.attrs = edev->attrs_muex;
1211 
1212 	}
1213 
1214 	if (edev->max_supported) {
1215 		edev->extcon_dev_type.groups =
1216 			kcalloc(edev->max_supported + 2,
1217 				sizeof(struct attribute_group *),
1218 				GFP_KERNEL);
1219 		if (!edev->extcon_dev_type.groups) {
1220 			ret = -ENOMEM;
1221 			goto err_alloc_groups;
1222 		}
1223 
1224 		edev->extcon_dev_type.name = dev_name(&edev->dev);
1225 		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
1226 
1227 		for (index = 0; index < edev->max_supported; index++)
1228 			edev->extcon_dev_type.groups[index] =
1229 				&edev->cables[index].attr_g;
1230 		if (edev->mutually_exclusive)
1231 			edev->extcon_dev_type.groups[index] =
1232 				&edev->attr_g_muex;
1233 
1234 		edev->dev.type = &edev->extcon_dev_type;
1235 	}
1236 
1237 	spin_lock_init(&edev->lock);
1238 	if (edev->max_supported) {
1239 		edev->nh = kcalloc(edev->max_supported, sizeof(*edev->nh),
1240 				GFP_KERNEL);
1241 		if (!edev->nh) {
1242 			ret = -ENOMEM;
1243 			goto err_alloc_nh;
1244 		}
1245 	}
1246 
1247 	for (index = 0; index < edev->max_supported; index++)
1248 		RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]);
1249 
1250 	RAW_INIT_NOTIFIER_HEAD(&edev->nh_all);
1251 
1252 	dev_set_drvdata(&edev->dev, edev);
1253 	edev->state = 0;
1254 
1255 	ret = device_register(&edev->dev);
1256 	if (ret) {
1257 		put_device(&edev->dev);
1258 		goto err_dev;
1259 	}
1260 
1261 	mutex_lock(&extcon_dev_list_lock);
1262 	list_add(&edev->entry, &extcon_dev_list);
1263 	mutex_unlock(&extcon_dev_list_lock);
1264 
1265 	return 0;
1266 
1267 err_dev:
1268 	if (edev->max_supported)
1269 		kfree(edev->nh);
1270 err_alloc_nh:
1271 	if (edev->max_supported)
1272 		kfree(edev->extcon_dev_type.groups);
1273 err_alloc_groups:
1274 	if (edev->max_supported && edev->mutually_exclusive) {
1275 		for (index = 0; edev->mutually_exclusive[index]; index++)
1276 			kfree(edev->d_attrs_muex[index].attr.name);
1277 		kfree(edev->d_attrs_muex);
1278 		kfree(edev->attrs_muex);
1279 	}
1280 err_muex:
1281 	for (index = 0; index < edev->max_supported; index++)
1282 		kfree(edev->cables[index].attr_g.name);
1283 err_alloc_cables:
1284 	if (edev->max_supported)
1285 		kfree(edev->cables);
1286 err_sysfs_alloc:
1287 	return ret;
1288 }
1289 EXPORT_SYMBOL_GPL(extcon_dev_register);
1290 
1291 /**
1292  * extcon_dev_unregister() - Unregister the extcon device.
1293  * @edev:	the extcon device to be unregistered.
1294  *
1295  * Note that this does not call kfree(edev) because edev was not allocated
1296  * by this class.
1297  */
1298 void extcon_dev_unregister(struct extcon_dev *edev)
1299 {
1300 	int index;
1301 
1302 	if (!edev)
1303 		return;
1304 
1305 	mutex_lock(&extcon_dev_list_lock);
1306 	list_del(&edev->entry);
1307 	mutex_unlock(&extcon_dev_list_lock);
1308 
1309 	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
1310 		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
1311 				dev_name(&edev->dev));
1312 		return;
1313 	}
1314 
1315 	device_unregister(&edev->dev);
1316 
1317 	if (edev->mutually_exclusive && edev->max_supported) {
1318 		for (index = 0; edev->mutually_exclusive[index];
1319 				index++)
1320 			kfree(edev->d_attrs_muex[index].attr.name);
1321 		kfree(edev->d_attrs_muex);
1322 		kfree(edev->attrs_muex);
1323 	}
1324 
1325 	for (index = 0; index < edev->max_supported; index++)
1326 		kfree(edev->cables[index].attr_g.name);
1327 
1328 	if (edev->max_supported) {
1329 		kfree(edev->extcon_dev_type.groups);
1330 		kfree(edev->cables);
1331 		kfree(edev->nh);
1332 	}
1333 
1334 	put_device(&edev->dev);
1335 }
1336 EXPORT_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  */
1346 struct 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);
1355 out:
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  */
1368 struct 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 
1396 struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1397 {
1398 	return ERR_PTR(-ENOSYS);
1399 }
1400 
1401 struct 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 
1408 EXPORT_SYMBOL_GPL(extcon_find_edev_by_node);
1409 EXPORT_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  */
1415 const char *extcon_get_edev_name(struct extcon_dev *edev)
1416 {
1417 	return !edev ? NULL : edev->name;
1418 }
1419 EXPORT_SYMBOL_GPL(extcon_get_edev_name);
1420 
1421 static int __init extcon_class_init(void)
1422 {
1423 	return create_extcon_class();
1424 }
1425 module_init(extcon_class_init);
1426 
1427 static void __exit extcon_class_exit(void)
1428 {
1429 	class_destroy(extcon_class);
1430 }
1431 module_exit(extcon_class_exit);
1432 
1433 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
1434 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1435 MODULE_DESCRIPTION("External Connector (extcon) framework");
1436 MODULE_LICENSE("GPL v2");
1437