Merge tag 'mtd/for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux
[linux-2.6-microblaze.git] / drivers / extcon / extcon.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * drivers/extcon/extcon.c - External Connector (extcon) framework.
4  *
5  * Copyright (C) 2015 Samsung Electronics
6  * Author: Chanwoo Choi <cw00.choi@samsung.com>
7  *
8  * Copyright (C) 2012 Samsung Electronics
9  * Author: Donggeun Kim <dg77.kim@samsung.com>
10  * Author: MyungJoo Ham <myungjoo.ham@samsung.com>
11  *
12  * based on android/drivers/switch/switch_class.c
13  * Copyright (C) 2008 Google, Inc.
14  * Author: Mike Lockwood <lockwood@android.com>
15  */
16
17 #include <linux/module.h>
18 #include <linux/types.h>
19 #include <linux/init.h>
20 #include <linux/device.h>
21 #include <linux/fs.h>
22 #include <linux/err.h>
23 #include <linux/of.h>
24 #include <linux/slab.h>
25 #include <linux/sysfs.h>
26
27 #include "extcon.h"
28
29 #define SUPPORTED_CABLE_MAX     32
30
31 static const struct __extcon_info {
32         unsigned int type;
33         unsigned int id;
34         const char *name;
35
36 } extcon_info[] = {
37         [EXTCON_NONE] = {
38                 .type = EXTCON_TYPE_MISC,
39                 .id = EXTCON_NONE,
40                 .name = "NONE",
41         },
42
43         /* USB external connector */
44         [EXTCON_USB] = {
45                 .type = EXTCON_TYPE_USB,
46                 .id = EXTCON_USB,
47                 .name = "USB",
48         },
49         [EXTCON_USB_HOST] = {
50                 .type = EXTCON_TYPE_USB,
51                 .id = EXTCON_USB_HOST,
52                 .name = "USB-HOST",
53         },
54
55         /* Charging external connector */
56         [EXTCON_CHG_USB_SDP] = {
57                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
58                 .id = EXTCON_CHG_USB_SDP,
59                 .name = "SDP",
60         },
61         [EXTCON_CHG_USB_DCP] = {
62                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
63                 .id = EXTCON_CHG_USB_DCP,
64                 .name = "DCP",
65         },
66         [EXTCON_CHG_USB_CDP] = {
67                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
68                 .id = EXTCON_CHG_USB_CDP,
69                 .name = "CDP",
70         },
71         [EXTCON_CHG_USB_ACA] = {
72                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
73                 .id = EXTCON_CHG_USB_ACA,
74                 .name = "ACA",
75         },
76         [EXTCON_CHG_USB_FAST] = {
77                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
78                 .id = EXTCON_CHG_USB_FAST,
79                 .name = "FAST-CHARGER",
80         },
81         [EXTCON_CHG_USB_SLOW] = {
82                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
83                 .id = EXTCON_CHG_USB_SLOW,
84                 .name = "SLOW-CHARGER",
85         },
86         [EXTCON_CHG_WPT] = {
87                 .type = EXTCON_TYPE_CHG,
88                 .id = EXTCON_CHG_WPT,
89                 .name = "WPT",
90         },
91         [EXTCON_CHG_USB_PD] = {
92                 .type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
93                 .id = EXTCON_CHG_USB_PD,
94                 .name = "PD",
95         },
96
97         /* Jack external connector */
98         [EXTCON_JACK_MICROPHONE] = {
99                 .type = EXTCON_TYPE_JACK,
100                 .id = EXTCON_JACK_MICROPHONE,
101                 .name = "MICROPHONE",
102         },
103         [EXTCON_JACK_HEADPHONE] = {
104                 .type = EXTCON_TYPE_JACK,
105                 .id = EXTCON_JACK_HEADPHONE,
106                 .name = "HEADPHONE",
107         },
108         [EXTCON_JACK_LINE_IN] = {
109                 .type = EXTCON_TYPE_JACK,
110                 .id = EXTCON_JACK_LINE_IN,
111                 .name = "LINE-IN",
112         },
113         [EXTCON_JACK_LINE_OUT] = {
114                 .type = EXTCON_TYPE_JACK,
115                 .id = EXTCON_JACK_LINE_OUT,
116                 .name = "LINE-OUT",
117         },
118         [EXTCON_JACK_VIDEO_IN] = {
119                 .type = EXTCON_TYPE_JACK,
120                 .id = EXTCON_JACK_VIDEO_IN,
121                 .name = "VIDEO-IN",
122         },
123         [EXTCON_JACK_VIDEO_OUT] = {
124                 .type = EXTCON_TYPE_JACK,
125                 .id = EXTCON_JACK_VIDEO_OUT,
126                 .name = "VIDEO-OUT",
127         },
128         [EXTCON_JACK_SPDIF_IN] = {
129                 .type = EXTCON_TYPE_JACK,
130                 .id = EXTCON_JACK_SPDIF_IN,
131                 .name = "SPDIF-IN",
132         },
133         [EXTCON_JACK_SPDIF_OUT] = {
134                 .type = EXTCON_TYPE_JACK,
135                 .id = EXTCON_JACK_SPDIF_OUT,
136                 .name = "SPDIF-OUT",
137         },
138
139         /* Display external connector */
140         [EXTCON_DISP_HDMI] = {
141                 .type = EXTCON_TYPE_DISP,
142                 .id = EXTCON_DISP_HDMI,
143                 .name = "HDMI",
144         },
145         [EXTCON_DISP_MHL] = {
146                 .type = EXTCON_TYPE_DISP,
147                 .id = EXTCON_DISP_MHL,
148                 .name = "MHL",
149         },
150         [EXTCON_DISP_DVI] = {
151                 .type = EXTCON_TYPE_DISP,
152                 .id = EXTCON_DISP_DVI,
153                 .name = "DVI",
154         },
155         [EXTCON_DISP_VGA] = {
156                 .type = EXTCON_TYPE_DISP,
157                 .id = EXTCON_DISP_VGA,
158                 .name = "VGA",
159         },
160         [EXTCON_DISP_DP] = {
161                 .type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
162                 .id = EXTCON_DISP_DP,
163                 .name = "DP",
164         },
165         [EXTCON_DISP_HMD] = {
166                 .type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
167                 .id = EXTCON_DISP_HMD,
168                 .name = "HMD",
169         },
170
171         /* Miscellaneous external connector */
172         [EXTCON_DOCK] = {
173                 .type = EXTCON_TYPE_MISC,
174                 .id = EXTCON_DOCK,
175                 .name = "DOCK",
176         },
177         [EXTCON_JIG] = {
178                 .type = EXTCON_TYPE_MISC,
179                 .id = EXTCON_JIG,
180                 .name = "JIG",
181         },
182         [EXTCON_MECHANICAL] = {
183                 .type = EXTCON_TYPE_MISC,
184                 .id = EXTCON_MECHANICAL,
185                 .name = "MECHANICAL",
186         },
187
188         { /* sentinel */ }
189 };
190
191 /**
192  * struct extcon_cable - An internal data for an external connector.
193  * @edev:               the extcon device
194  * @cable_index:        the index of this cable in the edev
195  * @attr_g:             the attribute group for the cable
196  * @attr_name:          "name" sysfs entry
197  * @attr_state:         "state" sysfs entry
198  * @attrs:              the array pointing to attr_name and attr_state for attr_g
199  */
200 struct extcon_cable {
201         struct extcon_dev *edev;
202         int cable_index;
203
204         struct attribute_group attr_g;
205         struct device_attribute attr_name;
206         struct device_attribute attr_state;
207
208         struct attribute *attrs[3]; /* to be fed to attr_g.attrs */
209
210         union extcon_property_value usb_propval[EXTCON_PROP_USB_CNT];
211         union extcon_property_value chg_propval[EXTCON_PROP_CHG_CNT];
212         union extcon_property_value jack_propval[EXTCON_PROP_JACK_CNT];
213         union extcon_property_value disp_propval[EXTCON_PROP_DISP_CNT];
214
215         unsigned long usb_bits[BITS_TO_LONGS(EXTCON_PROP_USB_CNT)];
216         unsigned long chg_bits[BITS_TO_LONGS(EXTCON_PROP_CHG_CNT)];
217         unsigned long jack_bits[BITS_TO_LONGS(EXTCON_PROP_JACK_CNT)];
218         unsigned long disp_bits[BITS_TO_LONGS(EXTCON_PROP_DISP_CNT)];
219 };
220
221 static struct class *extcon_class;
222
223 static LIST_HEAD(extcon_dev_list);
224 static DEFINE_MUTEX(extcon_dev_list_lock);
225
226 static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
227 {
228         int i = 0;
229
230         if (!edev->mutually_exclusive)
231                 return 0;
232
233         for (i = 0; edev->mutually_exclusive[i]; i++) {
234                 int weight;
235                 u32 correspondants = new_state & edev->mutually_exclusive[i];
236
237                 /* calculate the total number of bits set */
238                 weight = hweight32(correspondants);
239                 if (weight > 1)
240                         return i + 1;
241         }
242
243         return 0;
244 }
245
246 static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id)
247 {
248         int i;
249
250         /* Find the the index of extcon cable in edev->supported_cable */
251         for (i = 0; i < edev->max_supported; i++) {
252                 if (edev->supported_cable[i] == id)
253                         return i;
254         }
255
256         return -EINVAL;
257 }
258
259 static int get_extcon_type(unsigned int prop)
260 {
261         switch (prop) {
262         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
263                 return EXTCON_TYPE_USB;
264         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
265                 return EXTCON_TYPE_CHG;
266         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
267                 return EXTCON_TYPE_JACK;
268         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
269                 return EXTCON_TYPE_DISP;
270         default:
271                 return -EINVAL;
272         }
273 }
274
275 static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index)
276 {
277         return !!(edev->state & BIT(index));
278 }
279
280 static bool is_extcon_changed(struct extcon_dev *edev, int index,
281                                 bool new_state)
282 {
283         int state = !!(edev->state & BIT(index));
284         return (state != new_state);
285 }
286
287 static bool is_extcon_property_supported(unsigned int id, unsigned int prop)
288 {
289         int type;
290
291         /* Check whether the property is supported or not. */
292         type = get_extcon_type(prop);
293         if (type < 0)
294                 return false;
295
296         /* Check whether a specific extcon id supports the property or not. */
297         return !!(extcon_info[id].type & type);
298 }
299
300 static int is_extcon_property_capability(struct extcon_dev *edev,
301                                 unsigned int id, int index,unsigned int prop)
302 {
303         struct extcon_cable *cable;
304         int type, ret;
305
306         /* Check whether the property is supported or not. */
307         type = get_extcon_type(prop);
308         if (type < 0)
309                 return type;
310
311         cable = &edev->cables[index];
312
313         switch (type) {
314         case EXTCON_TYPE_USB:
315                 ret = test_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
316                 break;
317         case EXTCON_TYPE_CHG:
318                 ret = test_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
319                 break;
320         case EXTCON_TYPE_JACK:
321                 ret = test_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
322                 break;
323         case EXTCON_TYPE_DISP:
324                 ret = test_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
325                 break;
326         default:
327                 ret = -EINVAL;
328         }
329
330         return ret;
331 }
332
333 static void init_property(struct extcon_dev *edev, unsigned int id, int index)
334 {
335         unsigned int type = extcon_info[id].type;
336         struct extcon_cable *cable = &edev->cables[index];
337
338         if (EXTCON_TYPE_USB & type)
339                 memset(cable->usb_propval, 0, sizeof(cable->usb_propval));
340         if (EXTCON_TYPE_CHG & type)
341                 memset(cable->chg_propval, 0, sizeof(cable->chg_propval));
342         if (EXTCON_TYPE_JACK & type)
343                 memset(cable->jack_propval, 0, sizeof(cable->jack_propval));
344         if (EXTCON_TYPE_DISP & type)
345                 memset(cable->disp_propval, 0, sizeof(cable->disp_propval));
346 }
347
348 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
349                           char *buf)
350 {
351         int i, count = 0;
352         struct extcon_dev *edev = dev_get_drvdata(dev);
353
354         if (edev->max_supported == 0)
355                 return sprintf(buf, "%u\n", edev->state);
356
357         for (i = 0; i < edev->max_supported; i++) {
358                 count += sprintf(buf + count, "%s=%d\n",
359                                 extcon_info[edev->supported_cable[i]].name,
360                                  !!(edev->state & BIT(i)));
361         }
362
363         return count;
364 }
365 static DEVICE_ATTR_RO(state);
366
367 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
368                 char *buf)
369 {
370         struct extcon_dev *edev = dev_get_drvdata(dev);
371
372         return sprintf(buf, "%s\n", edev->name);
373 }
374 static DEVICE_ATTR_RO(name);
375
376 static ssize_t cable_name_show(struct device *dev,
377                                struct device_attribute *attr, char *buf)
378 {
379         struct extcon_cable *cable = container_of(attr, struct extcon_cable,
380                                                   attr_name);
381         int i = cable->cable_index;
382
383         return sprintf(buf, "%s\n",
384                         extcon_info[cable->edev->supported_cable[i]].name);
385 }
386
387 static ssize_t cable_state_show(struct device *dev,
388                                 struct device_attribute *attr, char *buf)
389 {
390         struct extcon_cable *cable = container_of(attr, struct extcon_cable,
391                                                   attr_state);
392
393         int i = cable->cable_index;
394
395         return sprintf(buf, "%d\n",
396                 extcon_get_state(cable->edev, cable->edev->supported_cable[i]));
397 }
398
399 /**
400  * extcon_sync() - Synchronize the state for an external connector.
401  * @edev:       the extcon device
402  *
403  * Note that this function send a notification in order to synchronize
404  * the state and property of an external connector.
405  *
406  * Returns 0 if success or error number if fail.
407  */
408 int extcon_sync(struct extcon_dev *edev, unsigned int id)
409 {
410         char name_buf[120];
411         char state_buf[120];
412         char *prop_buf;
413         char *envp[3];
414         int env_offset = 0;
415         int length;
416         int index;
417         int state;
418         unsigned long flags;
419
420         if (!edev)
421                 return -EINVAL;
422
423         index = find_cable_index_by_id(edev, id);
424         if (index < 0)
425                 return index;
426
427         spin_lock_irqsave(&edev->lock, flags);
428         state = !!(edev->state & BIT(index));
429         spin_unlock_irqrestore(&edev->lock, flags);
430
431         /*
432          * Call functions in a raw notifier chain for the specific one
433          * external connector.
434          */
435         raw_notifier_call_chain(&edev->nh[index], state, edev);
436
437         /*
438          * Call functions in a raw notifier chain for the all supported
439          * external connectors.
440          */
441         raw_notifier_call_chain(&edev->nh_all, state, edev);
442
443         spin_lock_irqsave(&edev->lock, flags);
444         /* This could be in interrupt handler */
445         prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
446         if (!prop_buf) {
447                 /* Unlock early before uevent */
448                 spin_unlock_irqrestore(&edev->lock, flags);
449
450                 dev_err(&edev->dev, "out of memory in extcon_set_state\n");
451                 kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE);
452
453                 return -ENOMEM;
454         }
455
456         length = name_show(&edev->dev, NULL, prop_buf);
457         if (length > 0) {
458                 if (prop_buf[length - 1] == '\n')
459                         prop_buf[length - 1] = 0;
460                 snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf);
461                 envp[env_offset++] = name_buf;
462         }
463
464         length = state_show(&edev->dev, NULL, prop_buf);
465         if (length > 0) {
466                 if (prop_buf[length - 1] == '\n')
467                         prop_buf[length - 1] = 0;
468                 snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf);
469                 envp[env_offset++] = state_buf;
470         }
471         envp[env_offset] = NULL;
472
473         /* Unlock early before uevent */
474         spin_unlock_irqrestore(&edev->lock, flags);
475         kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp);
476         free_page((unsigned long)prop_buf);
477
478         return 0;
479 }
480 EXPORT_SYMBOL_GPL(extcon_sync);
481
482 /**
483  * extcon_get_state() - Get the state of an external connector.
484  * @edev:       the extcon device
485  * @id:         the unique id indicating an external connector
486  *
487  * Returns 0 if success or error number if fail.
488  */
489 int extcon_get_state(struct extcon_dev *edev, const unsigned int id)
490 {
491         int index, state;
492         unsigned long flags;
493
494         if (!edev)
495                 return -EINVAL;
496
497         index = find_cable_index_by_id(edev, id);
498         if (index < 0)
499                 return index;
500
501         spin_lock_irqsave(&edev->lock, flags);
502         state = is_extcon_attached(edev, index);
503         spin_unlock_irqrestore(&edev->lock, flags);
504
505         return state;
506 }
507 EXPORT_SYMBOL_GPL(extcon_get_state);
508
509 /**
510  * extcon_set_state() - Set the state of an external connector.
511  * @edev:       the extcon device
512  * @id:         the unique id indicating an external connector
513  * @state:      the new state of an external connector.
514  *              the default semantics is true: attached / false: detached.
515  *
516  * Note that this function set the state of an external connector without
517  * a notification. To synchronize the state of an external connector,
518  * have to use extcon_set_state_sync() and extcon_sync().
519  *
520  * Returns 0 if success or error number if fail.
521  */
522 int extcon_set_state(struct extcon_dev *edev, unsigned int id, bool state)
523 {
524         unsigned long flags;
525         int index, ret = 0;
526
527         if (!edev)
528                 return -EINVAL;
529
530         index = find_cable_index_by_id(edev, id);
531         if (index < 0)
532                 return index;
533
534         spin_lock_irqsave(&edev->lock, flags);
535
536         /* Check whether the external connector's state is changed. */
537         if (!is_extcon_changed(edev, index, state))
538                 goto out;
539
540         if (check_mutually_exclusive(edev,
541                 (edev->state & ~BIT(index)) | (state & BIT(index)))) {
542                 ret = -EPERM;
543                 goto out;
544         }
545
546         /*
547          * Initialize the value of extcon property before setting
548          * the detached state for an external connector.
549          */
550         if (!state)
551                 init_property(edev, id, index);
552
553         /* Update the state for an external connector. */
554         if (state)
555                 edev->state |= BIT(index);
556         else
557                 edev->state &= ~(BIT(index));
558 out:
559         spin_unlock_irqrestore(&edev->lock, flags);
560
561         return ret;
562 }
563 EXPORT_SYMBOL_GPL(extcon_set_state);
564
565 /**
566  * extcon_set_state_sync() - Set the state of an external connector with sync.
567  * @edev:       the extcon device
568  * @id:         the unique id indicating an external connector
569  * @state:      the new state of external connector.
570  *              the default semantics is true: attached / false: detached.
571  *
572  * Note that this function set the state of external connector
573  * and synchronize the state by sending a notification.
574  *
575  * Returns 0 if success or error number if fail.
576  */
577 int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id, bool state)
578 {
579         int ret, index;
580         unsigned long flags;
581
582         index = find_cable_index_by_id(edev, id);
583         if (index < 0)
584                 return index;
585
586         /* Check whether the external connector's state is changed. */
587         spin_lock_irqsave(&edev->lock, flags);
588         ret = is_extcon_changed(edev, index, state);
589         spin_unlock_irqrestore(&edev->lock, flags);
590         if (!ret)
591                 return 0;
592
593         ret = extcon_set_state(edev, id, state);
594         if (ret < 0)
595                 return ret;
596
597         return extcon_sync(edev, id);
598 }
599 EXPORT_SYMBOL_GPL(extcon_set_state_sync);
600
601 /**
602  * extcon_get_property() - Get the property value of an external connector.
603  * @edev:       the extcon device
604  * @id:         the unique id indicating an external connector
605  * @prop:       the property id indicating an extcon property
606  * @prop_val:   the pointer which store the value of extcon property
607  *
608  * Note that when getting the property value of external connector,
609  * the external connector should be attached. If detached state, function
610  * return 0 without property value. Also, the each property should be
611  * included in the list of supported properties according to extcon type.
612  *
613  * Returns 0 if success or error number if fail.
614  */
615 int extcon_get_property(struct extcon_dev *edev, unsigned int id,
616                                 unsigned int prop,
617                                 union extcon_property_value *prop_val)
618 {
619         struct extcon_cable *cable;
620         unsigned long flags;
621         int index, ret = 0;
622
623         *prop_val = (union extcon_property_value){0};
624
625         if (!edev)
626                 return -EINVAL;
627
628         /* Check whether the property is supported or not */
629         if (!is_extcon_property_supported(id, prop))
630                 return -EINVAL;
631
632         /* Find the cable index of external connector by using id */
633         index = find_cable_index_by_id(edev, id);
634         if (index < 0)
635                 return index;
636
637         spin_lock_irqsave(&edev->lock, flags);
638
639         /* Check whether the property is available or not. */
640         if (!is_extcon_property_capability(edev, id, index, prop)) {
641                 spin_unlock_irqrestore(&edev->lock, flags);
642                 return -EPERM;
643         }
644
645         /*
646          * Check whether the external connector is attached.
647          * If external connector is detached, the user can not
648          * get the property value.
649          */
650         if (!is_extcon_attached(edev, index)) {
651                 spin_unlock_irqrestore(&edev->lock, flags);
652                 return 0;
653         }
654
655         cable = &edev->cables[index];
656
657         /* Get the property value according to extcon type */
658         switch (prop) {
659         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
660                 *prop_val = cable->usb_propval[prop - EXTCON_PROP_USB_MIN];
661                 break;
662         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
663                 *prop_val = cable->chg_propval[prop - EXTCON_PROP_CHG_MIN];
664                 break;
665         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
666                 *prop_val = cable->jack_propval[prop - EXTCON_PROP_JACK_MIN];
667                 break;
668         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
669                 *prop_val = cable->disp_propval[prop - EXTCON_PROP_DISP_MIN];
670                 break;
671         default:
672                 ret = -EINVAL;
673                 break;
674         }
675
676         spin_unlock_irqrestore(&edev->lock, flags);
677
678         return ret;
679 }
680 EXPORT_SYMBOL_GPL(extcon_get_property);
681
682 /**
683  * extcon_set_property() - Set the property value of an external connector.
684  * @edev:       the extcon device
685  * @id:         the unique id indicating an external connector
686  * @prop:       the property id indicating an extcon property
687  * @prop_val:   the pointer including the new value of extcon property
688  *
689  * Note that each property should be included in the list of supported
690  * properties according to the extcon type.
691  *
692  * Returns 0 if success or error number if fail.
693  */
694 int extcon_set_property(struct extcon_dev *edev, unsigned int id,
695                                 unsigned int prop,
696                                 union extcon_property_value prop_val)
697 {
698         struct extcon_cable *cable;
699         unsigned long flags;
700         int index, ret = 0;
701
702         if (!edev)
703                 return -EINVAL;
704
705         /* Check whether the property is supported or not */
706         if (!is_extcon_property_supported(id, prop))
707                 return -EINVAL;
708
709         /* Find the cable index of external connector by using id */
710         index = find_cable_index_by_id(edev, id);
711         if (index < 0)
712                 return index;
713
714         spin_lock_irqsave(&edev->lock, flags);
715
716         /* Check whether the property is available or not. */
717         if (!is_extcon_property_capability(edev, id, index, prop)) {
718                 spin_unlock_irqrestore(&edev->lock, flags);
719                 return -EPERM;
720         }
721
722         cable = &edev->cables[index];
723
724         /* Set the property value according to extcon type */
725         switch (prop) {
726         case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
727                 cable->usb_propval[prop - EXTCON_PROP_USB_MIN] = prop_val;
728                 break;
729         case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
730                 cable->chg_propval[prop - EXTCON_PROP_CHG_MIN] = prop_val;
731                 break;
732         case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
733                 cable->jack_propval[prop - EXTCON_PROP_JACK_MIN] = prop_val;
734                 break;
735         case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
736                 cable->disp_propval[prop - EXTCON_PROP_DISP_MIN] = prop_val;
737                 break;
738         default:
739                 ret = -EINVAL;
740                 break;
741         }
742
743         spin_unlock_irqrestore(&edev->lock, flags);
744
745         return ret;
746 }
747 EXPORT_SYMBOL_GPL(extcon_set_property);
748
749 /**
750  * extcon_set_property_sync() - Set property of an external connector with sync.
751  * @prop_val:   the pointer including the new value of extcon property
752  *
753  * Note that when setting the property value of external connector,
754  * the external connector should be attached. The each property should
755  * be included in the list of supported properties according to extcon type.
756  *
757  * Returns 0 if success or error number if fail.
758  */
759 int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id,
760                                 unsigned int prop,
761                                 union extcon_property_value prop_val)
762 {
763         int ret;
764
765         ret = extcon_set_property(edev, id, prop, prop_val);
766         if (ret < 0)
767                 return ret;
768
769         return extcon_sync(edev, id);
770 }
771 EXPORT_SYMBOL_GPL(extcon_set_property_sync);
772
773 /**
774  * extcon_get_property_capability() - Get the capability of the property
775  *                                      for an external connector.
776  * @edev:       the extcon device
777  * @id:         the unique id indicating an external connector
778  * @prop:       the property id indicating an extcon property
779  *
780  * Returns 1 if the property is available or 0 if not available.
781  */
782 int extcon_get_property_capability(struct extcon_dev *edev, unsigned int id,
783                                         unsigned int prop)
784 {
785         int index;
786
787         if (!edev)
788                 return -EINVAL;
789
790         /* Check whether the property is supported or not */
791         if (!is_extcon_property_supported(id, prop))
792                 return -EINVAL;
793
794         /* Find the cable index of external connector by using id */
795         index = find_cable_index_by_id(edev, id);
796         if (index < 0)
797                 return index;
798
799         return is_extcon_property_capability(edev, id, index, prop);
800 }
801 EXPORT_SYMBOL_GPL(extcon_get_property_capability);
802
803 /**
804  * extcon_set_property_capability() - Set the capability of the property
805  *                                      for an external connector.
806  * @edev:       the extcon device
807  * @id:         the unique id indicating an external connector
808  * @prop:       the property id indicating an extcon property
809  *
810  * Note that this function set the capability of the property
811  * for an external connector in order to mark the bit in capability
812  * bitmap which mean the available state of the property.
813  *
814  * Returns 0 if success or error number if fail.
815  */
816 int extcon_set_property_capability(struct extcon_dev *edev, unsigned int id,
817                                         unsigned int prop)
818 {
819         struct extcon_cable *cable;
820         int index, type, ret = 0;
821
822         if (!edev)
823                 return -EINVAL;
824
825         /* Check whether the property is supported or not. */
826         if (!is_extcon_property_supported(id, prop))
827                 return -EINVAL;
828
829         /* Find the cable index of external connector by using id. */
830         index = find_cable_index_by_id(edev, id);
831         if (index < 0)
832                 return index;
833
834         type = get_extcon_type(prop);
835         if (type < 0)
836                 return type;
837
838         cable = &edev->cables[index];
839
840         switch (type) {
841         case EXTCON_TYPE_USB:
842                 __set_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
843                 break;
844         case EXTCON_TYPE_CHG:
845                 __set_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
846                 break;
847         case EXTCON_TYPE_JACK:
848                 __set_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
849                 break;
850         case EXTCON_TYPE_DISP:
851                 __set_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
852                 break;
853         default:
854                 ret = -EINVAL;
855         }
856
857         return ret;
858 }
859 EXPORT_SYMBOL_GPL(extcon_set_property_capability);
860
861 /**
862  * extcon_get_extcon_dev() - Get the extcon device instance from the name.
863  * @extcon_name:        the extcon name provided with extcon_dev_register()
864  *
865  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
866  */
867 struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
868 {
869         struct extcon_dev *sd;
870
871         if (!extcon_name)
872                 return ERR_PTR(-EINVAL);
873
874         mutex_lock(&extcon_dev_list_lock);
875         list_for_each_entry(sd, &extcon_dev_list, entry) {
876                 if (!strcmp(sd->name, extcon_name))
877                         goto out;
878         }
879         sd = NULL;
880 out:
881         mutex_unlock(&extcon_dev_list_lock);
882         return sd;
883 }
884 EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
885
886 /**
887  * extcon_register_notifier() - Register a notifier block to get notified by
888  *                              any state changes from the extcon.
889  * @edev:       the extcon device
890  * @id:         the unique id indicating an external connector
891  * @nb:         a notifier block to be registered
892  *
893  * Note that the second parameter given to the callback of nb (val) is
894  * the current state of an external connector and the third pameter
895  * is the pointer of extcon device.
896  *
897  * Returns 0 if success or error number if fail.
898  */
899 int extcon_register_notifier(struct extcon_dev *edev, unsigned int id,
900                              struct notifier_block *nb)
901 {
902         unsigned long flags;
903         int ret, idx;
904
905         if (!edev || !nb)
906                 return -EINVAL;
907
908         idx = find_cable_index_by_id(edev, id);
909         if (idx < 0)
910                 return idx;
911
912         spin_lock_irqsave(&edev->lock, flags);
913         ret = raw_notifier_chain_register(&edev->nh[idx], nb);
914         spin_unlock_irqrestore(&edev->lock, flags);
915
916         return ret;
917 }
918 EXPORT_SYMBOL_GPL(extcon_register_notifier);
919
920 /**
921  * extcon_unregister_notifier() - Unregister a notifier block from the extcon.
922  * @edev:       the extcon device
923  * @id:         the unique id indicating an external connector
924  * @nb:         a notifier block to be registered
925  *
926  * Returns 0 if success or error number if fail.
927  */
928 int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id,
929                                 struct notifier_block *nb)
930 {
931         unsigned long flags;
932         int ret, idx;
933
934         if (!edev || !nb)
935                 return -EINVAL;
936
937         idx = find_cable_index_by_id(edev, id);
938         if (idx < 0)
939                 return idx;
940
941         spin_lock_irqsave(&edev->lock, flags);
942         ret = raw_notifier_chain_unregister(&edev->nh[idx], nb);
943         spin_unlock_irqrestore(&edev->lock, flags);
944
945         return ret;
946 }
947 EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
948
949 /**
950  * extcon_register_notifier_all() - Register a notifier block for all connectors.
951  * @edev:       the extcon device
952  * @nb:         a notifier block to be registered
953  *
954  * Note that this function registers a notifier block in order to receive
955  * the state change of all supported external connectors from extcon device.
956  * And the second parameter given to the callback of nb (val) is
957  * the current state and the third pameter is the pointer of extcon device.
958  *
959  * Returns 0 if success or error number if fail.
960  */
961 int extcon_register_notifier_all(struct extcon_dev *edev,
962                                 struct notifier_block *nb)
963 {
964         unsigned long flags;
965         int ret;
966
967         if (!edev || !nb)
968                 return -EINVAL;
969
970         spin_lock_irqsave(&edev->lock, flags);
971         ret = raw_notifier_chain_register(&edev->nh_all, nb);
972         spin_unlock_irqrestore(&edev->lock, flags);
973
974         return ret;
975 }
976 EXPORT_SYMBOL_GPL(extcon_register_notifier_all);
977
978 /**
979  * extcon_unregister_notifier_all() - Unregister a notifier block from extcon.
980  * @edev:       the extcon device
981  * @nb:         a notifier block to be registered
982  *
983  * Returns 0 if success or error number if fail.
984  */
985 int extcon_unregister_notifier_all(struct extcon_dev *edev,
986                                 struct notifier_block *nb)
987 {
988         unsigned long flags;
989         int ret;
990
991         if (!edev || !nb)
992                 return -EINVAL;
993
994         spin_lock_irqsave(&edev->lock, flags);
995         ret = raw_notifier_chain_unregister(&edev->nh_all, nb);
996         spin_unlock_irqrestore(&edev->lock, flags);
997
998         return ret;
999 }
1000 EXPORT_SYMBOL_GPL(extcon_unregister_notifier_all);
1001
1002 static struct attribute *extcon_attrs[] = {
1003         &dev_attr_state.attr,
1004         &dev_attr_name.attr,
1005         NULL,
1006 };
1007 ATTRIBUTE_GROUPS(extcon);
1008
1009 static int create_extcon_class(void)
1010 {
1011         if (!extcon_class) {
1012                 extcon_class = class_create(THIS_MODULE, "extcon");
1013                 if (IS_ERR(extcon_class))
1014                         return PTR_ERR(extcon_class);
1015                 extcon_class->dev_groups = extcon_groups;
1016         }
1017
1018         return 0;
1019 }
1020
1021 static void extcon_dev_release(struct device *dev)
1022 {
1023 }
1024
1025 static const char *muex_name = "mutually_exclusive";
1026 static void dummy_sysfs_dev_release(struct device *dev)
1027 {
1028 }
1029
1030 /*
1031  * extcon_dev_allocate() - Allocate the memory of extcon device.
1032  * @supported_cable:    the array of the supported external connectors
1033  *                      ending with EXTCON_NONE.
1034  *
1035  * Note that this function allocates the memory for extcon device 
1036  * and initialize default setting for the extcon device.
1037  *
1038  * Returns the pointer memory of allocated extcon_dev if success
1039  * or ERR_PTR(err) if fail.
1040  */
1041 struct extcon_dev *extcon_dev_allocate(const unsigned int *supported_cable)
1042 {
1043         struct extcon_dev *edev;
1044
1045         if (!supported_cable)
1046                 return ERR_PTR(-EINVAL);
1047
1048         edev = kzalloc(sizeof(*edev), GFP_KERNEL);
1049         if (!edev)
1050                 return ERR_PTR(-ENOMEM);
1051
1052         edev->max_supported = 0;
1053         edev->supported_cable = supported_cable;
1054
1055         return edev;
1056 }
1057
1058 /*
1059  * extcon_dev_free() - Free the memory of extcon device.
1060  * @edev:       the extcon device
1061  */
1062 void extcon_dev_free(struct extcon_dev *edev)
1063 {
1064         kfree(edev);
1065 }
1066 EXPORT_SYMBOL_GPL(extcon_dev_free);
1067
1068 /**
1069  * extcon_dev_register() - Register an new extcon device
1070  * @edev:       the extcon device to be registered
1071  *
1072  * Among the members of edev struct, please set the "user initializing data"
1073  * do not set the values of "internal data", which are initialized by
1074  * this function.
1075  *
1076  * Note that before calling this funciton, have to allocate the memory
1077  * of an extcon device by using the extcon_dev_allocate(). And the extcon
1078  * dev should include the supported_cable information.
1079  *
1080  * Returns 0 if success or error number if fail.
1081  */
1082 int extcon_dev_register(struct extcon_dev *edev)
1083 {
1084         int ret, index = 0;
1085         static atomic_t edev_no = ATOMIC_INIT(-1);
1086
1087         if (!extcon_class) {
1088                 ret = create_extcon_class();
1089                 if (ret < 0)
1090                         return ret;
1091         }
1092
1093         if (!edev || !edev->supported_cable)
1094                 return -EINVAL;
1095
1096         for (; edev->supported_cable[index] != EXTCON_NONE; index++);
1097
1098         edev->max_supported = index;
1099         if (index > SUPPORTED_CABLE_MAX) {
1100                 dev_err(&edev->dev,
1101                         "exceed the maximum number of supported cables\n");
1102                 return -EINVAL;
1103         }
1104
1105         edev->dev.class = extcon_class;
1106         edev->dev.release = extcon_dev_release;
1107
1108         edev->name = dev_name(edev->dev.parent);
1109         if (IS_ERR_OR_NULL(edev->name)) {
1110                 dev_err(&edev->dev,
1111                         "extcon device name is null\n");
1112                 return -EINVAL;
1113         }
1114         dev_set_name(&edev->dev, "extcon%lu",
1115                         (unsigned long)atomic_inc_return(&edev_no));
1116
1117         if (edev->max_supported) {
1118                 char *str;
1119                 struct extcon_cable *cable;
1120
1121                 edev->cables = kcalloc(edev->max_supported,
1122                                        sizeof(struct extcon_cable),
1123                                        GFP_KERNEL);
1124                 if (!edev->cables) {
1125                         ret = -ENOMEM;
1126                         goto err_sysfs_alloc;
1127                 }
1128                 for (index = 0; index < edev->max_supported; index++) {
1129                         cable = &edev->cables[index];
1130
1131                         str = kasprintf(GFP_KERNEL, "cable.%d", index);
1132                         if (!str) {
1133                                 for (index--; index >= 0; index--) {
1134                                         cable = &edev->cables[index];
1135                                         kfree(cable->attr_g.name);
1136                                 }
1137                                 ret = -ENOMEM;
1138
1139                                 goto err_alloc_cables;
1140                         }
1141
1142                         cable->edev = edev;
1143                         cable->cable_index = index;
1144                         cable->attrs[0] = &cable->attr_name.attr;
1145                         cable->attrs[1] = &cable->attr_state.attr;
1146                         cable->attrs[2] = NULL;
1147                         cable->attr_g.name = str;
1148                         cable->attr_g.attrs = cable->attrs;
1149
1150                         sysfs_attr_init(&cable->attr_name.attr);
1151                         cable->attr_name.attr.name = "name";
1152                         cable->attr_name.attr.mode = 0444;
1153                         cable->attr_name.show = cable_name_show;
1154
1155                         sysfs_attr_init(&cable->attr_state.attr);
1156                         cable->attr_state.attr.name = "state";
1157                         cable->attr_state.attr.mode = 0444;
1158                         cable->attr_state.show = cable_state_show;
1159                 }
1160         }
1161
1162         if (edev->max_supported && edev->mutually_exclusive) {
1163                 char *name;
1164
1165                 /* Count the size of mutually_exclusive array */
1166                 for (index = 0; edev->mutually_exclusive[index]; index++)
1167                         ;
1168
1169                 edev->attrs_muex = kcalloc(index + 1,
1170                                            sizeof(struct attribute *),
1171                                            GFP_KERNEL);
1172                 if (!edev->attrs_muex) {
1173                         ret = -ENOMEM;
1174                         goto err_muex;
1175                 }
1176
1177                 edev->d_attrs_muex = kcalloc(index,
1178                                              sizeof(struct device_attribute),
1179                                              GFP_KERNEL);
1180                 if (!edev->d_attrs_muex) {
1181                         ret = -ENOMEM;
1182                         kfree(edev->attrs_muex);
1183                         goto err_muex;
1184                 }
1185
1186                 for (index = 0; edev->mutually_exclusive[index]; index++) {
1187                         name = kasprintf(GFP_KERNEL, "0x%x",
1188                                          edev->mutually_exclusive[index]);
1189                         if (!name) {
1190                                 for (index--; index >= 0; index--) {
1191                                         kfree(edev->d_attrs_muex[index].attr.
1192                                               name);
1193                                 }
1194                                 kfree(edev->d_attrs_muex);
1195                                 kfree(edev->attrs_muex);
1196                                 ret = -ENOMEM;
1197                                 goto err_muex;
1198                         }
1199                         sysfs_attr_init(&edev->d_attrs_muex[index].attr);
1200                         edev->d_attrs_muex[index].attr.name = name;
1201                         edev->d_attrs_muex[index].attr.mode = 0000;
1202                         edev->attrs_muex[index] = &edev->d_attrs_muex[index]
1203                                                         .attr;
1204                 }
1205                 edev->attr_g_muex.name = muex_name;
1206                 edev->attr_g_muex.attrs = edev->attrs_muex;
1207
1208         }
1209
1210         if (edev->max_supported) {
1211                 edev->extcon_dev_type.groups =
1212                         kcalloc(edev->max_supported + 2,
1213                                 sizeof(struct attribute_group *),
1214                                 GFP_KERNEL);
1215                 if (!edev->extcon_dev_type.groups) {
1216                         ret = -ENOMEM;
1217                         goto err_alloc_groups;
1218                 }
1219
1220                 edev->extcon_dev_type.name = dev_name(&edev->dev);
1221                 edev->extcon_dev_type.release = dummy_sysfs_dev_release;
1222
1223                 for (index = 0; index < edev->max_supported; index++)
1224                         edev->extcon_dev_type.groups[index] =
1225                                 &edev->cables[index].attr_g;
1226                 if (edev->mutually_exclusive)
1227                         edev->extcon_dev_type.groups[index] =
1228                                 &edev->attr_g_muex;
1229
1230                 edev->dev.type = &edev->extcon_dev_type;
1231         }
1232
1233         ret = device_register(&edev->dev);
1234         if (ret) {
1235                 put_device(&edev->dev);
1236                 goto err_dev;
1237         }
1238
1239         spin_lock_init(&edev->lock);
1240         edev->nh = devm_kcalloc(&edev->dev, edev->max_supported,
1241                                 sizeof(*edev->nh), GFP_KERNEL);
1242         if (!edev->nh) {
1243                 ret = -ENOMEM;
1244                 device_unregister(&edev->dev);
1245                 goto err_dev;
1246         }
1247
1248         for (index = 0; index < edev->max_supported; index++)
1249                 RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]);
1250
1251         RAW_INIT_NOTIFIER_HEAD(&edev->nh_all);
1252
1253         dev_set_drvdata(&edev->dev, edev);
1254         edev->state = 0;
1255
1256         mutex_lock(&extcon_dev_list_lock);
1257         list_add(&edev->entry, &extcon_dev_list);
1258         mutex_unlock(&extcon_dev_list_lock);
1259
1260         return 0;
1261
1262 err_dev:
1263         if (edev->max_supported)
1264                 kfree(edev->extcon_dev_type.groups);
1265 err_alloc_groups:
1266         if (edev->max_supported && edev->mutually_exclusive) {
1267                 for (index = 0; edev->mutually_exclusive[index]; index++)
1268                         kfree(edev->d_attrs_muex[index].attr.name);
1269                 kfree(edev->d_attrs_muex);
1270                 kfree(edev->attrs_muex);
1271         }
1272 err_muex:
1273         for (index = 0; index < edev->max_supported; index++)
1274                 kfree(edev->cables[index].attr_g.name);
1275 err_alloc_cables:
1276         if (edev->max_supported)
1277                 kfree(edev->cables);
1278 err_sysfs_alloc:
1279         return ret;
1280 }
1281 EXPORT_SYMBOL_GPL(extcon_dev_register);
1282
1283 /**
1284  * extcon_dev_unregister() - Unregister the extcon device.
1285  * @edev:       the extcon device to be unregistered.
1286  *
1287  * Note that this does not call kfree(edev) because edev was not allocated
1288  * by this class.
1289  */
1290 void extcon_dev_unregister(struct extcon_dev *edev)
1291 {
1292         int index;
1293
1294         if (!edev)
1295                 return;
1296
1297         mutex_lock(&extcon_dev_list_lock);
1298         list_del(&edev->entry);
1299         mutex_unlock(&extcon_dev_list_lock);
1300
1301         if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
1302                 dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
1303                                 dev_name(&edev->dev));
1304                 return;
1305         }
1306
1307         device_unregister(&edev->dev);
1308
1309         if (edev->mutually_exclusive && edev->max_supported) {
1310                 for (index = 0; edev->mutually_exclusive[index];
1311                                 index++)
1312                         kfree(edev->d_attrs_muex[index].attr.name);
1313                 kfree(edev->d_attrs_muex);
1314                 kfree(edev->attrs_muex);
1315         }
1316
1317         for (index = 0; index < edev->max_supported; index++)
1318                 kfree(edev->cables[index].attr_g.name);
1319
1320         if (edev->max_supported) {
1321                 kfree(edev->extcon_dev_type.groups);
1322                 kfree(edev->cables);
1323         }
1324
1325         put_device(&edev->dev);
1326 }
1327 EXPORT_SYMBOL_GPL(extcon_dev_unregister);
1328
1329 #ifdef CONFIG_OF
1330
1331 /*
1332  * extcon_find_edev_by_node - Find the extcon device from devicetree.
1333  * @node        : OF node identifying edev
1334  *
1335  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
1336  */
1337 struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1338 {
1339         struct extcon_dev *edev;
1340
1341         mutex_lock(&extcon_dev_list_lock);
1342         list_for_each_entry(edev, &extcon_dev_list, entry)
1343                 if (edev->dev.parent && edev->dev.parent->of_node == node)
1344                         goto out;
1345         edev = ERR_PTR(-EPROBE_DEFER);
1346 out:
1347         mutex_unlock(&extcon_dev_list_lock);
1348
1349         return edev;
1350 }
1351
1352 /*
1353  * extcon_get_edev_by_phandle - Get the extcon device from devicetree.
1354  * @dev         : the instance to the given device
1355  * @index       : the index into list of extcon_dev
1356  *
1357  * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
1358  */
1359 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1360 {
1361         struct device_node *node;
1362         struct extcon_dev *edev;
1363
1364         if (!dev)
1365                 return ERR_PTR(-EINVAL);
1366
1367         if (!dev->of_node) {
1368                 dev_dbg(dev, "device does not have a device node entry\n");
1369                 return ERR_PTR(-EINVAL);
1370         }
1371
1372         node = of_parse_phandle(dev->of_node, "extcon", index);
1373         if (!node) {
1374                 dev_dbg(dev, "failed to get phandle in %pOF node\n",
1375                         dev->of_node);
1376                 return ERR_PTR(-ENODEV);
1377         }
1378
1379         edev = extcon_find_edev_by_node(node);
1380         of_node_put(node);
1381
1382         return edev;
1383 }
1384
1385 #else
1386
1387 struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
1388 {
1389         return ERR_PTR(-ENOSYS);
1390 }
1391
1392 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1393 {
1394         return ERR_PTR(-ENOSYS);
1395 }
1396
1397 #endif /* CONFIG_OF */
1398
1399 EXPORT_SYMBOL_GPL(extcon_find_edev_by_node);
1400 EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
1401
1402 /**
1403  * extcon_get_edev_name() - Get the name of the extcon device.
1404  * @edev:       the extcon device
1405  */
1406 const char *extcon_get_edev_name(struct extcon_dev *edev)
1407 {
1408         return !edev ? NULL : edev->name;
1409 }
1410 EXPORT_SYMBOL_GPL(extcon_get_edev_name);
1411
1412 static int __init extcon_class_init(void)
1413 {
1414         return create_extcon_class();
1415 }
1416 module_init(extcon_class_init);
1417
1418 static void __exit extcon_class_exit(void)
1419 {
1420         class_destroy(extcon_class);
1421 }
1422 module_exit(extcon_class_exit);
1423
1424 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
1425 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1426 MODULE_DESCRIPTION("External Connector (extcon) framework");
1427 MODULE_LICENSE("GPL v2");