xref: /linux/drivers/extcon/extcon.c (revision 856e7c4b619af622d56b3b454f7bec32a170ac99)
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 
39 static 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  */
208 struct 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 
229 static struct class *extcon_class;
230 
231 static LIST_HEAD(extcon_dev_list);
232 static DEFINE_MUTEX(extcon_dev_list_lock);
233 
234 static 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 
254 static 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 
267 static 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 
283 static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index)
284 {
285 	return !!(edev->state & BIT(index));
286 }
287 
288 static 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 
295 static 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 
308 static 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 
341 static 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 
356 static 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 }
373 static DEVICE_ATTR_RO(state);
374 
375 static 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 }
382 static DEVICE_ATTR_RO(name);
383 
384 static 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 
395 static 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  */
416 int 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 }
487 EXPORT_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  */
496 int 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 }
514 EXPORT_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  */
529 int 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));
565 out:
566 	spin_unlock_irqrestore(&edev->lock, flags);
567 
568 	return ret;
569 }
570 EXPORT_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  */
584 int 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 }
606 EXPORT_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  */
622 int 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 }
687 EXPORT_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  */
701 int 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 }
754 EXPORT_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  */
766 int 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 }
778 EXPORT_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  */
789 int 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 }
808 EXPORT_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  */
823 int 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 }
866 EXPORT_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  */
874 struct 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;
887 out:
888 	mutex_unlock(&extcon_dev_list_lock);
889 	return sd;
890 }
891 EXPORT_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  */
906 int 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 }
925 EXPORT_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  */
935 int 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 }
954 EXPORT_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  */
968 int 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 }
983 EXPORT_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  */
992 int 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 }
1007 EXPORT_SYMBOL_GPL(extcon_unregister_notifier_all);
1008 
1009 static struct attribute *extcon_attrs[] = {
1010 	&dev_attr_state.attr,
1011 	&dev_attr_name.attr,
1012 	NULL,
1013 };
1014 ATTRIBUTE_GROUPS(extcon);
1015 
1016 static 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 
1028 static void extcon_dev_release(struct device *dev)
1029 {
1030 }
1031 
1032 static const char *muex_name = "mutually_exclusive";
1033 static 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  */
1048 struct 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  */
1069 void extcon_dev_free(struct extcon_dev *edev)
1070 {
1071 	kfree(edev);
1072 }
1073 EXPORT_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  */
1089 int 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 = kcalloc(edev->max_supported,
1130 				       sizeof(struct extcon_cable),
1131 				       GFP_KERNEL);
1132 		if (!edev->cables) {
1133 			ret = -ENOMEM;
1134 			goto err_sysfs_alloc;
1135 		}
1136 		for (index = 0; index < edev->max_supported; index++) {
1137 			cable = &edev->cables[index];
1138 
1139 			snprintf(buf, 10, "cable.%d", index);
1140 			str = kzalloc(strlen(buf) + 1,
1141 				      GFP_KERNEL);
1142 			if (!str) {
1143 				for (index--; index >= 0; index--) {
1144 					cable = &edev->cables[index];
1145 					kfree(cable->attr_g.name);
1146 				}
1147 				ret = -ENOMEM;
1148 
1149 				goto err_alloc_cables;
1150 			}
1151 			strcpy(str, buf);
1152 
1153 			cable->edev = edev;
1154 			cable->cable_index = index;
1155 			cable->attrs[0] = &cable->attr_name.attr;
1156 			cable->attrs[1] = &cable->attr_state.attr;
1157 			cable->attrs[2] = NULL;
1158 			cable->attr_g.name = str;
1159 			cable->attr_g.attrs = cable->attrs;
1160 
1161 			sysfs_attr_init(&cable->attr_name.attr);
1162 			cable->attr_name.attr.name = "name";
1163 			cable->attr_name.attr.mode = 0444;
1164 			cable->attr_name.show = cable_name_show;
1165 
1166 			sysfs_attr_init(&cable->attr_state.attr);
1167 			cable->attr_state.attr.name = "state";
1168 			cable->attr_state.attr.mode = 0444;
1169 			cable->attr_state.show = cable_state_show;
1170 		}
1171 	}
1172 
1173 	if (edev->max_supported && edev->mutually_exclusive) {
1174 		char buf[80];
1175 		char *name;
1176 
1177 		/* Count the size of mutually_exclusive array */
1178 		for (index = 0; edev->mutually_exclusive[index]; index++)
1179 			;
1180 
1181 		edev->attrs_muex = kcalloc(index + 1,
1182 					   sizeof(struct attribute *),
1183 					   GFP_KERNEL);
1184 		if (!edev->attrs_muex) {
1185 			ret = -ENOMEM;
1186 			goto err_muex;
1187 		}
1188 
1189 		edev->d_attrs_muex = kcalloc(index,
1190 					     sizeof(struct device_attribute),
1191 					     GFP_KERNEL);
1192 		if (!edev->d_attrs_muex) {
1193 			ret = -ENOMEM;
1194 			kfree(edev->attrs_muex);
1195 			goto err_muex;
1196 		}
1197 
1198 		for (index = 0; edev->mutually_exclusive[index]; index++) {
1199 			sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
1200 			name = kzalloc(strlen(buf) + 1,
1201 				       GFP_KERNEL);
1202 			if (!name) {
1203 				for (index--; index >= 0; index--) {
1204 					kfree(edev->d_attrs_muex[index].attr.
1205 					      name);
1206 				}
1207 				kfree(edev->d_attrs_muex);
1208 				kfree(edev->attrs_muex);
1209 				ret = -ENOMEM;
1210 				goto err_muex;
1211 			}
1212 			strcpy(name, buf);
1213 			sysfs_attr_init(&edev->d_attrs_muex[index].attr);
1214 			edev->d_attrs_muex[index].attr.name = name;
1215 			edev->d_attrs_muex[index].attr.mode = 0000;
1216 			edev->attrs_muex[index] = &edev->d_attrs_muex[index]
1217 							.attr;
1218 		}
1219 		edev->attr_g_muex.name = muex_name;
1220 		edev->attr_g_muex.attrs = edev->attrs_muex;
1221 
1222 	}
1223 
1224 	if (edev->max_supported) {
1225 		edev->extcon_dev_type.groups =
1226 			kcalloc(edev->max_supported + 2,
1227 				sizeof(struct attribute_group *),
1228 				GFP_KERNEL);
1229 		if (!edev->extcon_dev_type.groups) {
1230 			ret = -ENOMEM;
1231 			goto err_alloc_groups;
1232 		}
1233 
1234 		edev->extcon_dev_type.name = dev_name(&edev->dev);
1235 		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
1236 
1237 		for (index = 0; index < edev->max_supported; index++)
1238 			edev->extcon_dev_type.groups[index] =
1239 				&edev->cables[index].attr_g;
1240 		if (edev->mutually_exclusive)
1241 			edev->extcon_dev_type.groups[index] =
1242 				&edev->attr_g_muex;
1243 
1244 		edev->dev.type = &edev->extcon_dev_type;
1245 	}
1246 
1247 	ret = device_register(&edev->dev);
1248 	if (ret) {
1249 		put_device(&edev->dev);
1250 		goto err_dev;
1251 	}
1252 
1253 	spin_lock_init(&edev->lock);
1254 	edev->nh = devm_kcalloc(&edev->dev, edev->max_supported,
1255 				sizeof(*edev->nh), GFP_KERNEL);
1256 	if (!edev->nh) {
1257 		ret = -ENOMEM;
1258 		goto err_dev;
1259 	}
1260 
1261 	for (index = 0; index < edev->max_supported; index++)
1262 		RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]);
1263 
1264 	RAW_INIT_NOTIFIER_HEAD(&edev->nh_all);
1265 
1266 	dev_set_drvdata(&edev->dev, edev);
1267 	edev->state = 0;
1268 
1269 	mutex_lock(&extcon_dev_list_lock);
1270 	list_add(&edev->entry, &extcon_dev_list);
1271 	mutex_unlock(&extcon_dev_list_lock);
1272 
1273 	return 0;
1274 
1275 err_dev:
1276 	if (edev->max_supported)
1277 		kfree(edev->extcon_dev_type.groups);
1278 err_alloc_groups:
1279 	if (edev->max_supported && edev->mutually_exclusive) {
1280 		for (index = 0; edev->mutually_exclusive[index]; index++)
1281 			kfree(edev->d_attrs_muex[index].attr.name);
1282 		kfree(edev->d_attrs_muex);
1283 		kfree(edev->attrs_muex);
1284 	}
1285 err_muex:
1286 	for (index = 0; index < edev->max_supported; index++)
1287 		kfree(edev->cables[index].attr_g.name);
1288 err_alloc_cables:
1289 	if (edev->max_supported)
1290 		kfree(edev->cables);
1291 err_sysfs_alloc:
1292 	return ret;
1293 }
1294 EXPORT_SYMBOL_GPL(extcon_dev_register);
1295 
1296 /**
1297  * extcon_dev_unregister() - Unregister the extcon device.
1298  * @edev:	the extcon device to be unregistered.
1299  *
1300  * Note that this does not call kfree(edev) because edev was not allocated
1301  * by this class.
1302  */
1303 void extcon_dev_unregister(struct extcon_dev *edev)
1304 {
1305 	int index;
1306 
1307 	if (!edev)
1308 		return;
1309 
1310 	mutex_lock(&extcon_dev_list_lock);
1311 	list_del(&edev->entry);
1312 	mutex_unlock(&extcon_dev_list_lock);
1313 
1314 	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
1315 		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
1316 				dev_name(&edev->dev));
1317 		return;
1318 	}
1319 
1320 	device_unregister(&edev->dev);
1321 
1322 	if (edev->mutually_exclusive && edev->max_supported) {
1323 		for (index = 0; edev->mutually_exclusive[index];
1324 				index++)
1325 			kfree(edev->d_attrs_muex[index].attr.name);
1326 		kfree(edev->d_attrs_muex);
1327 		kfree(edev->attrs_muex);
1328 	}
1329 
1330 	for (index = 0; index < edev->max_supported; index++)
1331 		kfree(edev->cables[index].attr_g.name);
1332 
1333 	if (edev->max_supported) {
1334 		kfree(edev->extcon_dev_type.groups);
1335 		kfree(edev->cables);
1336 	}
1337 
1338 	put_device(&edev->dev);
1339 }
1340 EXPORT_SYMBOL_GPL(extcon_dev_unregister);
1341 
1342 #ifdef CONFIG_OF
1343 
1344 /*
1345  * extcon_find_edev_by_node - Find the extcon device from devicetree.
1346  * @node	: OF node identifying edev
1347  *
1348  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
1349  */
1350 struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1351 {
1352 	struct extcon_dev *edev;
1353 
1354 	mutex_lock(&extcon_dev_list_lock);
1355 	list_for_each_entry(edev, &extcon_dev_list, entry)
1356 		if (edev->dev.parent && edev->dev.parent->of_node == node)
1357 			goto out;
1358 	edev = ERR_PTR(-EPROBE_DEFER);
1359 out:
1360 	mutex_unlock(&extcon_dev_list_lock);
1361 
1362 	return edev;
1363 }
1364 
1365 /*
1366  * extcon_get_edev_by_phandle - Get the extcon device from devicetree.
1367  * @dev		: the instance to the given device
1368  * @index	: the index into list of extcon_dev
1369  *
1370  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
1371  */
1372 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1373 {
1374 	struct device_node *node;
1375 	struct extcon_dev *edev;
1376 
1377 	if (!dev)
1378 		return ERR_PTR(-EINVAL);
1379 
1380 	if (!dev->of_node) {
1381 		dev_dbg(dev, "device does not have a device node entry\n");
1382 		return ERR_PTR(-EINVAL);
1383 	}
1384 
1385 	node = of_parse_phandle(dev->of_node, "extcon", index);
1386 	if (!node) {
1387 		dev_dbg(dev, "failed to get phandle in %pOF node\n",
1388 			dev->of_node);
1389 		return ERR_PTR(-ENODEV);
1390 	}
1391 
1392 	edev = extcon_find_edev_by_node(node);
1393 	of_node_put(node);
1394 
1395 	return edev;
1396 }
1397 
1398 #else
1399 
1400 struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1401 {
1402 	return ERR_PTR(-ENOSYS);
1403 }
1404 
1405 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1406 {
1407 	return ERR_PTR(-ENOSYS);
1408 }
1409 
1410 #endif /* CONFIG_OF */
1411 
1412 EXPORT_SYMBOL_GPL(extcon_find_edev_by_node);
1413 EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
1414 
1415 /**
1416  * extcon_get_edev_name() - Get the name of the extcon device.
1417  * @edev:	the extcon device
1418  */
1419 const char *extcon_get_edev_name(struct extcon_dev *edev)
1420 {
1421 	return !edev ? NULL : edev->name;
1422 }
1423 
1424 static int __init extcon_class_init(void)
1425 {
1426 	return create_extcon_class();
1427 }
1428 module_init(extcon_class_init);
1429 
1430 static void __exit extcon_class_exit(void)
1431 {
1432 	class_destroy(extcon_class);
1433 }
1434 module_exit(extcon_class_exit);
1435 
1436 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
1437 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1438 MODULE_DESCRIPTION("External Connector (extcon) framework");
1439 MODULE_LICENSE("GPL v2");
1440