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  1/*
  2 *  drivers/extcon/extcon_class.c
  3 *
  4 *  External connector (extcon) class driver
  5 *
  6 * Copyright (C) 2012 Samsung Electronics
  7 * Author: Donggeun Kim <dg77.kim@samsung.com>
  8 * Author: MyungJoo Ham <myungjoo.ham@samsung.com>
  9 *
 10 * based on android/drivers/switch/switch_class.c
 11 * Copyright (C) 2008 Google, Inc.
 12 * Author: Mike Lockwood <lockwood@android.com>
 13 *
 14 * This software is licensed under the terms of the GNU General Public
 15 * License version 2, as published by the Free Software Foundation, and
 16 * may be copied, distributed, and modified under those terms.
 17 *
 18 * This program is distributed in the hope that it will be useful,
 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 21 * GNU General Public License for more details.
 22 *
 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/extcon.h>
 32#include <linux/slab.h>
 33
 34/*
 35 * extcon_cable_name suggests the standard cable names for commonly used
 36 * cable types.
 37 *
 38 * However, please do not use extcon_cable_name directly for extcon_dev
 39 * struct's supported_cable pointer unless your device really supports
 40 * every single port-type of the following cable names. Please choose cable
 41 * names that are actually used in your extcon device.
 42 */
 43const char *extcon_cable_name[] = {
 44	[EXTCON_USB]		= "USB",
 45	[EXTCON_USB_HOST]	= "USB-Host",
 46	[EXTCON_TA]		= "TA",
 47	[EXTCON_FAST_CHARGER]	= "Fast-charger",
 48	[EXTCON_SLOW_CHARGER]	= "Slow-charger",
 49	[EXTCON_CHARGE_DOWNSTREAM]	= "Charge-downstream",
 50	[EXTCON_HDMI]		= "HDMI",
 51	[EXTCON_MHL]		= "MHL",
 52	[EXTCON_DVI]		= "DVI",
 53	[EXTCON_VGA]		= "VGA",
 54	[EXTCON_DOCK]		= "Dock",
 55	[EXTCON_LINE_IN]	= "Line-in",
 56	[EXTCON_LINE_OUT]	= "Line-out",
 57	[EXTCON_MIC_IN]		= "Microphone",
 58	[EXTCON_HEADPHONE_OUT]	= "Headphone",
 59	[EXTCON_SPDIF_IN]	= "SPDIF-in",
 60	[EXTCON_SPDIF_OUT]	= "SPDIF-out",
 61	[EXTCON_VIDEO_IN]	= "Video-in",
 62	[EXTCON_VIDEO_OUT]	= "Video-out",
 63	[EXTCON_MECHANICAL]	= "Mechanical",
 64
 65	NULL,
 66};
 67
 68struct class *extcon_class;
 69#if defined(CONFIG_ANDROID)
 70static struct class_compat *switch_class;
 71#endif /* CONFIG_ANDROID */
 72
 73static LIST_HEAD(extcon_dev_list);
 74static DEFINE_MUTEX(extcon_dev_list_lock);
 75
 76/**
 77 * check_mutually_exclusive - Check if new_state violates mutually_exclusive
 78 *			    condition.
 79 * @edev:	the extcon device
 80 * @new_state:	new cable attach status for @edev
 81 *
 82 * Returns 0 if nothing violates. Returns the index + 1 for the first
 83 * violated condition.
 84 */
 85static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
 86{
 87	int i = 0;
 88
 89	if (!edev->mutually_exclusive)
 90		return 0;
 91
 92	for (i = 0; edev->mutually_exclusive[i]; i++) {
 93		int count = 0, j;
 94		u32 correspondants = new_state & edev->mutually_exclusive[i];
 95		u32 exp = 1;
 96
 97		for (j = 0; j < 32; j++) {
 98			if (exp & correspondants)
 99				count++;
100			if (count > 1)
101				return i + 1;
102			exp <<= 1;
103		}
104	}
105
106	return 0;
107}
108
109static ssize_t state_show(struct device *dev, struct device_attribute *attr,
110			  char *buf)
111{
112	int i, count = 0;
113	struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev);
114
115	if (edev->print_state) {
116		int ret = edev->print_state(edev, buf);
117
118		if (ret >= 0)
119			return ret;
120		/* Use default if failed */
121	}
122
123	if (edev->max_supported == 0)
124		return sprintf(buf, "%u\n", edev->state);
125
126	for (i = 0; i < SUPPORTED_CABLE_MAX; i++) {
127		if (!edev->supported_cable[i])
128			break;
129		count += sprintf(buf + count, "%s=%d\n",
130				 edev->supported_cable[i],
131				 !!(edev->state & (1 << i)));
132	}
133
134	return count;
135}
136
137int extcon_set_state(struct extcon_dev *edev, u32 state);
138static ssize_t state_store(struct device *dev, struct device_attribute *attr,
139			   const char *buf, size_t count)
140{
141	u32 state;
142	ssize_t ret = 0;
143	struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev);
144
145	ret = sscanf(buf, "0x%x", &state);
146	if (ret == 0)
147		ret = -EINVAL;
148	else
149		ret = extcon_set_state(edev, state);
150
151	if (ret < 0)
152		return ret;
153
154	return count;
155}
156
157static ssize_t name_show(struct device *dev, struct device_attribute *attr,
158		char *buf)
159{
160	struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev);
161
162	/* Optional callback given by the user */
163	if (edev->print_name) {
164		int ret = edev->print_name(edev, buf);
165		if (ret >= 0)
166			return ret;
167	}
168
169	return sprintf(buf, "%s\n", dev_name(edev->dev));
170}
171
172static ssize_t cable_name_show(struct device *dev,
173			       struct device_attribute *attr, char *buf)
174{
175	struct extcon_cable *cable = container_of(attr, struct extcon_cable,
176						  attr_name);
177
178	return sprintf(buf, "%s\n",
179		       cable->edev->supported_cable[cable->cable_index]);
180}
181
182static ssize_t cable_state_show(struct device *dev,
183				struct device_attribute *attr, char *buf)
184{
185	struct extcon_cable *cable = container_of(attr, struct extcon_cable,
186						  attr_state);
187
188	return sprintf(buf, "%d\n",
189		       extcon_get_cable_state_(cable->edev,
190					       cable->cable_index));
191}
192
193static ssize_t cable_state_store(struct device *dev,
194				 struct device_attribute *attr, const char *buf,
195				 size_t count)
196{
197	struct extcon_cable *cable = container_of(attr, struct extcon_cable,
198						  attr_state);
199	int ret, state;
200
201	ret = sscanf(buf, "%d", &state);
202	if (ret == 0)
203		ret = -EINVAL;
204	else
205		ret = extcon_set_cable_state_(cable->edev, cable->cable_index,
206					      state);
207
208	if (ret < 0)
209		return ret;
210	return count;
211}
212
213/**
214 * extcon_update_state() - Update the cable attach states of the extcon device
215 *			only for the masked bits.
216 * @edev:	the extcon device
217 * @mask:	the bit mask to designate updated bits.
218 * @state:	new cable attach status for @edev
219 *
220 * Changing the state sends uevent with environment variable containing
221 * the name of extcon device (envp[0]) and the state output (envp[1]).
222 * Tizen uses this format for extcon device to get events from ports.
223 * Android uses this format as well.
224 *
225 * Note that the notifier provides which bits are changed in the state
226 * variable with the val parameter (second) to the callback.
227 */
228int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state)
229{
230	char name_buf[120];
231	char state_buf[120];
232	char *prop_buf;
233	char *envp[3];
234	int env_offset = 0;
235	int length;
236	unsigned long flags;
237
238	spin_lock_irqsave(&edev->lock, flags);
239
240	if (edev->state != ((edev->state & ~mask) | (state & mask))) {
241		u32 old_state = edev->state;
242
243		if (check_mutually_exclusive(edev, (edev->state & ~mask) |
244						   (state & mask))) {
245			spin_unlock_irqrestore(&edev->lock, flags);
246			return -EPERM;
247		}
248
249		edev->state &= ~mask;
250		edev->state |= state & mask;
251
252		raw_notifier_call_chain(&edev->nh, old_state, edev);
253
254		/* This could be in interrupt handler */
255		prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
256		if (prop_buf) {
257			length = name_show(edev->dev, NULL, prop_buf);
258			if (length > 0) {
259				if (prop_buf[length - 1] == '\n')
260					prop_buf[length - 1] = 0;
261				snprintf(name_buf, sizeof(name_buf),
262					"NAME=%s", prop_buf);
263				envp[env_offset++] = name_buf;
264			}
265			length = state_show(edev->dev, NULL, prop_buf);
266			if (length > 0) {
267				if (prop_buf[length - 1] == '\n')
268					prop_buf[length - 1] = 0;
269				snprintf(state_buf, sizeof(state_buf),
270					"STATE=%s", prop_buf);
271				envp[env_offset++] = state_buf;
272			}
273			envp[env_offset] = NULL;
274			/* Unlock early before uevent */
275			spin_unlock_irqrestore(&edev->lock, flags);
276
277			kobject_uevent_env(&edev->dev->kobj, KOBJ_CHANGE, envp);
278			free_page((unsigned long)prop_buf);
279		} else {
280			/* Unlock early before uevent */
281			spin_unlock_irqrestore(&edev->lock, flags);
282
283			dev_err(edev->dev, "out of memory in extcon_set_state\n");
284			kobject_uevent(&edev->dev->kobj, KOBJ_CHANGE);
285		}
286	} else {
287		/* No changes */
288		spin_unlock_irqrestore(&edev->lock, flags);
289	}
290
291	return 0;
292}
293EXPORT_SYMBOL_GPL(extcon_update_state);
294
295/**
296 * extcon_set_state() - Set the cable attach states of the extcon device.
297 * @edev:	the extcon device
298 * @state:	new cable attach status for @edev
299 *
300 * Note that notifier provides which bits are changed in the state
301 * variable with the val parameter (second) to the callback.
302 */
303int extcon_set_state(struct extcon_dev *edev, u32 state)
304{
305	return extcon_update_state(edev, 0xffffffff, state);
306}
307EXPORT_SYMBOL_GPL(extcon_set_state);
308
309/**
310 * extcon_find_cable_index() - Get the cable index based on the cable name.
311 * @edev:	the extcon device that has the cable.
312 * @cable_name:	cable name to be searched.
313 *
314 * Note that accessing a cable state based on cable_index is faster than
315 * cable_name because using cable_name induces a loop with strncmp().
316 * Thus, when get/set_cable_state is repeatedly used, using cable_index
317 * is recommended.
318 */
319int extcon_find_cable_index(struct extcon_dev *edev, const char *cable_name)
320{
321	int i;
322
323	if (edev->supported_cable) {
324		for (i = 0; edev->supported_cable[i]; i++) {
325			if (!strncmp(edev->supported_cable[i],
326				cable_name, CABLE_NAME_MAX))
327				return i;
328		}
329	}
330
331	return -EINVAL;
332}
333EXPORT_SYMBOL_GPL(extcon_find_cable_index);
334
335/**
336 * extcon_get_cable_state_() - Get the status of a specific cable.
337 * @edev:	the extcon device that has the cable.
338 * @index:	cable index that can be retrieved by extcon_find_cable_index().
339 */
340int extcon_get_cable_state_(struct extcon_dev *edev, int index)
341{
342	if (index < 0 || (edev->max_supported && edev->max_supported <= index))
343		return -EINVAL;
344
345	return !!(edev->state & (1 << index));
346}
347EXPORT_SYMBOL_GPL(extcon_get_cable_state_);
348
349/**
350 * extcon_get_cable_state() - Get the status of a specific cable.
351 * @edev:	the extcon device that has the cable.
352 * @cable_name:	cable name.
353 *
354 * Note that this is slower than extcon_get_cable_state_.
355 */
356int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name)
357{
358	return extcon_get_cable_state_(edev, extcon_find_cable_index
359						(edev, cable_name));
360}
361EXPORT_SYMBOL_GPL(extcon_get_cable_state);
362
363/**
364 * extcon_get_cable_state_() - Set the status of a specific cable.
365 * @edev:	the extcon device that has the cable.
366 * @index:	cable index that can be retrieved by extcon_find_cable_index().
367 * @cable_state:	the new cable status. The default semantics is
368 *			true: attached / false: detached.
369 */
370int extcon_set_cable_state_(struct extcon_dev *edev,
371			int index, bool cable_state)
372{
373	u32 state;
374
375	if (index < 0 || (edev->max_supported && edev->max_supported <= index))
376		return -EINVAL;
377
378	state = cable_state ? (1 << index) : 0;
379	return extcon_update_state(edev, 1 << index, state);
380}
381EXPORT_SYMBOL_GPL(extcon_set_cable_state_);
382
383/**
384 * extcon_get_cable_state() - Set the status of a specific cable.
385 * @edev:	the extcon device that has the cable.
386 * @cable_name:	cable name.
387 * @cable_state:	the new cable status. The default semantics is
388 *			true: attached / false: detached.
389 *
390 * Note that this is slower than extcon_set_cable_state_.
391 */
392int extcon_set_cable_state(struct extcon_dev *edev,
393			const char *cable_name, bool cable_state)
394{
395	return extcon_set_cable_state_(edev, extcon_find_cable_index
396					(edev, cable_name), cable_state);
397}
398EXPORT_SYMBOL_GPL(extcon_set_cable_state);
399
400/**
401 * extcon_get_extcon_dev() - Get the extcon device instance from the name
402 * @extcon_name:	The extcon name provided with extcon_dev_register()
403 */
404struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
405{
406	struct extcon_dev *sd;
407
408	mutex_lock(&extcon_dev_list_lock);
409	list_for_each_entry(sd, &extcon_dev_list, entry) {
410		if (!strcmp(sd->name, extcon_name))
411			goto out;
412	}
413	sd = NULL;
414out:
415	mutex_unlock(&extcon_dev_list_lock);
416	return sd;
417}
418EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
419
420static int _call_per_cable(struct notifier_block *nb, unsigned long val,
421			   void *ptr)
422{
423	struct extcon_specific_cable_nb *obj = container_of(nb,
424			struct extcon_specific_cable_nb, internal_nb);
425	struct extcon_dev *edev = ptr;
426
427	if ((val & (1 << obj->cable_index)) !=
428	    (edev->state & (1 << obj->cable_index))) {
429		bool cable_state = true;
430
431		obj->previous_value = val;
432
433		if (val & (1 << obj->cable_index))
434			cable_state = false;
435
436		return obj->user_nb->notifier_call(obj->user_nb,
437				cable_state, ptr);
438	}
439
440	return NOTIFY_OK;
441}
442
443/**
444 * extcon_register_interest() - Register a notifier for a state change of a
445 *			      specific cable, not a entier set of cables of a
446 *			      extcon device.
447 * @obj:	an empty extcon_specific_cable_nb object to be returned.
448 * @extcon_name:	the name of extcon device.
449 * @cable_name:		the target cable name.
450 * @nb:		the notifier block to get notified.
451 *
452 * Provide an empty extcon_specific_cable_nb. extcon_register_interest() sets
453 * the struct for you.
454 *
455 * extcon_register_interest is a helper function for those who want to get
456 * notification for a single specific cable's status change. If a user wants
457 * to get notification for any changes of all cables of a extcon device,
458 * he/she should use the general extcon_register_notifier().
459 *
460 * Note that the second parameter given to the callback of nb (val) is
461 * "old_state", not the current state. The current state can be retrieved
462 * by looking at the third pameter (edev pointer)'s state value.
463 */
464int extcon_register_interest(struct extcon_specific_cable_nb *obj,
465			     const char *extcon_name, const char *cable_name,
466			     struct notifier_block *nb)
467{
468	if (!obj || !extcon_name || !cable_name || !nb)
469		return -EINVAL;
470
471	obj->edev = extcon_get_extcon_dev(extcon_name);
472	if (!obj->edev)
473		return -ENODEV;
474
475	obj->cable_index = extcon_find_cable_index(obj->edev, cable_name);
476	if (obj->cable_index < 0)
477		return -ENODEV;
478
479	obj->user_nb = nb;
480
481	obj->internal_nb.notifier_call = _call_per_cable;
482
483	return raw_notifier_chain_register(&obj->edev->nh, &obj->internal_nb);
484}
485
486/**
487 * extcon_unregister_interest() - Unregister the notifier registered by
488 *				extcon_register_interest().
489 * @obj:	the extcon_specific_cable_nb object returned by
490 *		extcon_register_interest().
491 */
492int extcon_unregister_interest(struct extcon_specific_cable_nb *obj)
493{
494	if (!obj)
495		return -EINVAL;
496
497	return raw_notifier_chain_unregister(&obj->edev->nh, &obj->internal_nb);
498}
499
500/**
501 * extcon_register_notifier() - Register a notifee to get notified by
502 *			      any attach status changes from the extcon.
503 * @edev:	the extcon device.
504 * @nb:		a notifier block to be registered.
505 *
506 * Note that the second parameter given to the callback of nb (val) is
507 * "old_state", not the current state. The current state can be retrieved
508 * by looking at the third pameter (edev pointer)'s state value.
509 */
510int extcon_register_notifier(struct extcon_dev *edev,
511			struct notifier_block *nb)
512{
513	return raw_notifier_chain_register(&edev->nh, nb);
514}
515EXPORT_SYMBOL_GPL(extcon_register_notifier);
516
517/**
518 * extcon_unregister_notifier() - Unregister a notifee from the extcon device.
519 * @edev:	the extcon device.
520 * @nb:		a registered notifier block to be unregistered.
521 */
522int extcon_unregister_notifier(struct extcon_dev *edev,
523			struct notifier_block *nb)
524{
525	return raw_notifier_chain_unregister(&edev->nh, nb);
526}
527EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
528
529static struct device_attribute extcon_attrs[] = {
530	__ATTR(state, S_IRUGO | S_IWUSR, state_show, state_store),
531	__ATTR_RO(name),
532	__ATTR_NULL,
533};
534
535static int create_extcon_class(void)
536{
537	if (!extcon_class) {
538		extcon_class = class_create(THIS_MODULE, "extcon");
539		if (IS_ERR(extcon_class))
540			return PTR_ERR(extcon_class);
541		extcon_class->dev_attrs = extcon_attrs;
542
543#if defined(CONFIG_ANDROID)
544		switch_class = class_compat_register("switch");
545		if (WARN(!switch_class, "cannot allocate"))
546			return -ENOMEM;
547#endif /* CONFIG_ANDROID */
548	}
549
550	return 0;
551}
552
553static void extcon_cleanup(struct extcon_dev *edev, bool skip)
554{
555	mutex_lock(&extcon_dev_list_lock);
556	list_del(&edev->entry);
557	mutex_unlock(&extcon_dev_list_lock);
558
559	if (!skip && get_device(edev->dev)) {
560		int index;
561
562		if (edev->mutually_exclusive && edev->max_supported) {
563			for (index = 0; edev->mutually_exclusive[index];
564			     index++)
565				kfree(edev->d_attrs_muex[index].attr.name);
566			kfree(edev->d_attrs_muex);
567			kfree(edev->attrs_muex);
568		}
569
570		for (index = 0; index < edev->max_supported; index++)
571			kfree(edev->cables[index].attr_g.name);
572
573		if (edev->max_supported) {
574			kfree(edev->extcon_dev_type.groups);
575			kfree(edev->cables);
576		}
577
578		device_unregister(edev->dev);
579		put_device(edev->dev);
580	}
581
582	kfree(edev->dev);
583}
584
585static void extcon_dev_release(struct device *dev)
586{
587	struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev);
588
589	extcon_cleanup(edev, true);
590}
591
592static const char *muex_name = "mutually_exclusive";
593static void dummy_sysfs_dev_release(struct device *dev)
594{
595}
596
597/**
598 * extcon_dev_register() - Register a new extcon device
599 * @edev	: the new extcon device (should be allocated before calling)
600 * @dev		: the parent device for this extcon device.
601 *
602 * Among the members of edev struct, please set the "user initializing data"
603 * in any case and set the "optional callbacks" if required. However, please
604 * do not set the values of "internal data", which are initialized by
605 * this function.
606 */
607int extcon_dev_register(struct extcon_dev *edev, struct device *dev)
608{
609	int ret, index = 0;
610
611	if (!extcon_class) {
612		ret = create_extcon_class();
613		if (ret < 0)
614			return ret;
615	}
616
617	if (edev->supported_cable) {
618		/* Get size of array */
619		for (index = 0; edev->supported_cable[index]; index++)
620			;
621		edev->max_supported = index;
622	} else {
623		edev->max_supported = 0;
624	}
625
626	if (index > SUPPORTED_CABLE_MAX) {
627		dev_err(edev->dev, "extcon: maximum number of supported cables exceeded.\n");
628		return -EINVAL;
629	}
630
631	edev->dev = kzalloc(sizeof(struct device), GFP_KERNEL);
632	if (!edev->dev)
633		return -ENOMEM;
634	edev->dev->parent = dev;
635	edev->dev->class = extcon_class;
636	edev->dev->release = extcon_dev_release;
637
638	dev_set_name(edev->dev, edev->name ? edev->name : dev_name(dev));
639
640	if (edev->max_supported) {
641		char buf[10];
642		char *str;
643		struct extcon_cable *cable;
644
645		edev->cables = kzalloc(sizeof(struct extcon_cable) *
646				       edev->max_supported, GFP_KERNEL);
647		if (!edev->cables) {
648			ret = -ENOMEM;
649			goto err_sysfs_alloc;
650		}
651		for (index = 0; index < edev->max_supported; index++) {
652			cable = &edev->cables[index];
653
654			snprintf(buf, 10, "cable.%d", index);
655			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
656				      GFP_KERNEL);
657			if (!str) {
658				for (index--; index >= 0; index--) {
659					cable = &edev->cables[index];
660					kfree(cable->attr_g.name);
661				}
662				ret = -ENOMEM;
663
664				goto err_alloc_cables;
665			}
666			strcpy(str, buf);
667
668			cable->edev = edev;
669			cable->cable_index = index;
670			cable->attrs[0] = &cable->attr_name.attr;
671			cable->attrs[1] = &cable->attr_state.attr;
672			cable->attrs[2] = NULL;
673			cable->attr_g.name = str;
674			cable->attr_g.attrs = cable->attrs;
675
676			cable->attr_name.attr.name = "name";
677			cable->attr_name.attr.mode = 0444;
678			cable->attr_name.show = cable_name_show;
679
680			cable->attr_state.attr.name = "state";
681			cable->attr_state.attr.mode = 0644;
682			cable->attr_state.show = cable_state_show;
683			cable->attr_state.store = cable_state_store;
684		}
685	}
686
687	if (edev->max_supported && edev->mutually_exclusive) {
688		char buf[80];
689		char *name;
690
691		/* Count the size of mutually_exclusive array */
692		for (index = 0; edev->mutually_exclusive[index]; index++)
693			;
694
695		edev->attrs_muex = kzalloc(sizeof(struct attribute *) *
696					   (index + 1), GFP_KERNEL);
697		if (!edev->attrs_muex) {
698			ret = -ENOMEM;
699			goto err_muex;
700		}
701
702		edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) *
703					     index, GFP_KERNEL);
704		if (!edev->d_attrs_muex) {
705			ret = -ENOMEM;
706			kfree(edev->attrs_muex);
707			goto err_muex;
708		}
709
710		for (index = 0; edev->mutually_exclusive[index]; index++) {
711			sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
712			name = kzalloc(sizeof(char) * (strlen(buf) + 1),
713				       GFP_KERNEL);
714			if (!name) {
715				for (index--; index >= 0; index--) {
716					kfree(edev->d_attrs_muex[index].attr.
717					      name);
718				}
719				kfree(edev->d_attrs_muex);
720				kfree(edev->attrs_muex);
721				ret = -ENOMEM;
722				goto err_muex;
723			}
724			strcpy(name, buf);
725			edev->d_attrs_muex[index].attr.name = name;
726			edev->d_attrs_muex[index].attr.mode = 0000;
727			edev->attrs_muex[index] = &edev->d_attrs_muex[index]
728							.attr;
729		}
730		edev->attr_g_muex.name = muex_name;
731		edev->attr_g_muex.attrs = edev->attrs_muex;
732
733	}
734
735	if (edev->max_supported) {
736		edev->extcon_dev_type.groups =
737			kzalloc(sizeof(struct attribute_group *) *
738				(edev->max_supported + 2), GFP_KERNEL);
739		if (!edev->extcon_dev_type.groups) {
740			ret = -ENOMEM;
741			goto err_alloc_groups;
742		}
743
744		edev->extcon_dev_type.name = dev_name(edev->dev);
745		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
746
747		for (index = 0; index < edev->max_supported; index++)
748			edev->extcon_dev_type.groups[index] =
749				&edev->cables[index].attr_g;
750		if (edev->mutually_exclusive)
751			edev->extcon_dev_type.groups[index] =
752				&edev->attr_g_muex;
753
754		edev->dev->type = &edev->extcon_dev_type;
755	}
756
757	ret = device_register(edev->dev);
758	if (ret) {
759		put_device(edev->dev);
760		goto err_dev;
761	}
762#if defined(CONFIG_ANDROID)
763	if (switch_class)
764		ret = class_compat_create_link(switch_class, edev->dev,
765					       NULL);
766#endif /* CONFIG_ANDROID */
767
768	spin_lock_init(&edev->lock);
769
770	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
771
772	dev_set_drvdata(edev->dev, edev);
773	edev->state = 0;
774
775	mutex_lock(&extcon_dev_list_lock);
776	list_add(&edev->entry, &extcon_dev_list);
777	mutex_unlock(&extcon_dev_list_lock);
778
779	return 0;
780
781err_dev:
782	if (edev->max_supported)
783		kfree(edev->extcon_dev_type.groups);
784err_alloc_groups:
785	if (edev->max_supported && edev->mutually_exclusive) {
786		for (index = 0; edev->mutually_exclusive[index]; index++)
787			kfree(edev->d_attrs_muex[index].attr.name);
788		kfree(edev->d_attrs_muex);
789		kfree(edev->attrs_muex);
790	}
791err_muex:
792	for (index = 0; index < edev->max_supported; index++)
793		kfree(edev->cables[index].attr_g.name);
794err_alloc_cables:
795	if (edev->max_supported)
796		kfree(edev->cables);
797err_sysfs_alloc:
798	kfree(edev->dev);
799	return ret;
800}
801EXPORT_SYMBOL_GPL(extcon_dev_register);
802
803/**
804 * extcon_dev_unregister() - Unregister the extcon device.
805 * @edev:	the extcon device instance to be unregitered.
806 *
807 * Note that this does not call kfree(edev) because edev was not allocated
808 * by this class.
809 */
810void extcon_dev_unregister(struct extcon_dev *edev)
811{
812	extcon_cleanup(edev, false);
813}
814EXPORT_SYMBOL_GPL(extcon_dev_unregister);
815
816static int __init extcon_class_init(void)
817{
818	return create_extcon_class();
819}
820module_init(extcon_class_init);
821
822static void __exit extcon_class_exit(void)
823{
824	class_destroy(extcon_class);
825}
826module_exit(extcon_class_exit);
827
828MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
829MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
830MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
831MODULE_DESCRIPTION("External connector (extcon) class driver");
832MODULE_LICENSE("GPL");