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 #include <linux/sysfs.h>
34
35 /*
36 * extcon_cable_name suggests the standard cable names for commonly used
37 * cable types.
38 *
39 * However, please do not use extcon_cable_name directly for extcon_dev
40 * struct's supported_cable pointer unless your device really supports
41 * every single port-type of the following cable names. Please choose cable
42 * names that are actually used in your extcon device.
43 */
44 const char extcon_cable_name[][CABLE_NAME_MAX + 1] = {
45 [EXTCON_USB] = "USB",
46 [EXTCON_USB_HOST] = "USB-Host",
47 [EXTCON_TA] = "TA",
48 [EXTCON_FAST_CHARGER] = "Fast-charger",
49 [EXTCON_SLOW_CHARGER] = "Slow-charger",
50 [EXTCON_CHARGE_DOWNSTREAM] = "Charge-downstream",
51 [EXTCON_HDMI] = "HDMI",
52 [EXTCON_MHL] = "MHL",
53 [EXTCON_DVI] = "DVI",
54 [EXTCON_VGA] = "VGA",
55 [EXTCON_DOCK] = "Dock",
56 [EXTCON_LINE_IN] = "Line-in",
57 [EXTCON_LINE_OUT] = "Line-out",
58 [EXTCON_MIC_IN] = "Microphone",
59 [EXTCON_HEADPHONE_OUT] = "Headphone",
60 [EXTCON_SPDIF_IN] = "SPDIF-in",
61 [EXTCON_SPDIF_OUT] = "SPDIF-out",
62 [EXTCON_VIDEO_IN] = "Video-in",
63 [EXTCON_VIDEO_OUT] = "Video-out",
64 [EXTCON_MECHANICAL] = "Mechanical",
65 };
66
67 static struct class *extcon_class;
68 #if defined(CONFIG_ANDROID)
69 static struct class_compat *switch_class;
70 #endif /* CONFIG_ANDROID */
71
72 static LIST_HEAD(extcon_dev_list);
73 static DEFINE_MUTEX(extcon_dev_list_lock);
74
75 /**
76 * check_mutually_exclusive - Check if new_state violates mutually_exclusive
77 * condition.
78 * @edev: the extcon device
79 * @new_state: new cable attach status for @edev
80 *
81 * Returns 0 if nothing violates. Returns the index + 1 for the first
82 * violated condition.
83 */
check_mutually_exclusive(struct extcon_dev * edev,u32 new_state)84 static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
85 {
86 int i = 0;
87
88 if (!edev->mutually_exclusive)
89 return 0;
90
91 for (i = 0; edev->mutually_exclusive[i]; i++) {
92 int weight;
93 u32 correspondants = new_state & edev->mutually_exclusive[i];
94
95 /* calculate the total number of bits set */
96 weight = hweight32(correspondants);
97 if (weight > 1)
98 return i + 1;
99 }
100
101 return 0;
102 }
103
state_show(struct device * dev,struct device_attribute * attr,char * buf)104 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
105 char *buf)
106 {
107 int i, count = 0;
108 struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev);
109
110 if (edev->print_state) {
111 int ret = edev->print_state(edev, buf);
112
113 if (ret >= 0)
114 return ret;
115 /* Use default if failed */
116 }
117
118 if (edev->max_supported == 0)
119 return sprintf(buf, "%u\n", edev->state);
120
121 for (i = 0; i < SUPPORTED_CABLE_MAX; i++) {
122 if (!edev->supported_cable[i])
123 break;
124 count += sprintf(buf + count, "%s=%d\n",
125 edev->supported_cable[i],
126 !!(edev->state & (1 << i)));
127 }
128
129 return count;
130 }
131
132 int extcon_set_state(struct extcon_dev *edev, u32 state);
state_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)133 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
134 const char *buf, size_t count)
135 {
136 u32 state;
137 ssize_t ret = 0;
138 struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev);
139
140 ret = sscanf(buf, "0x%x", &state);
141 if (ret == 0)
142 ret = -EINVAL;
143 else
144 ret = extcon_set_state(edev, state);
145
146 if (ret < 0)
147 return ret;
148
149 return count;
150 }
151
name_show(struct device * dev,struct device_attribute * attr,char * buf)152 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
153 char *buf)
154 {
155 struct extcon_dev *edev = (struct extcon_dev *) dev_get_drvdata(dev);
156
157 /* Optional callback given by the user */
158 if (edev->print_name) {
159 int ret = edev->print_name(edev, buf);
160 if (ret >= 0)
161 return ret;
162 }
163
164 return sprintf(buf, "%s\n", dev_name(edev->dev));
165 }
166
cable_name_show(struct device * dev,struct device_attribute * attr,char * buf)167 static ssize_t cable_name_show(struct device *dev,
168 struct device_attribute *attr, char *buf)
169 {
170 struct extcon_cable *cable = container_of(attr, struct extcon_cable,
171 attr_name);
172
173 return sprintf(buf, "%s\n",
174 cable->edev->supported_cable[cable->cable_index]);
175 }
176
cable_state_show(struct device * dev,struct device_attribute * attr,char * buf)177 static ssize_t cable_state_show(struct device *dev,
178 struct device_attribute *attr, char *buf)
179 {
180 struct extcon_cable *cable = container_of(attr, struct extcon_cable,
181 attr_state);
182
183 return sprintf(buf, "%d\n",
184 extcon_get_cable_state_(cable->edev,
185 cable->cable_index));
186 }
187
cable_state_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)188 static ssize_t cable_state_store(struct device *dev,
189 struct device_attribute *attr, const char *buf,
190 size_t count)
191 {
192 struct extcon_cable *cable = container_of(attr, struct extcon_cable,
193 attr_state);
194 int ret, state;
195
196 ret = sscanf(buf, "%d", &state);
197 if (ret == 0)
198 ret = -EINVAL;
199 else
200 ret = extcon_set_cable_state_(cable->edev, cable->cable_index,
201 state);
202
203 if (ret < 0)
204 return ret;
205 return count;
206 }
207
208 /**
209 * extcon_update_state() - Update the cable attach states of the extcon device
210 * only for the masked bits.
211 * @edev: the extcon device
212 * @mask: the bit mask to designate updated bits.
213 * @state: new cable attach status for @edev
214 *
215 * Changing the state sends uevent with environment variable containing
216 * the name of extcon device (envp[0]) and the state output (envp[1]).
217 * Tizen uses this format for extcon device to get events from ports.
218 * Android uses this format as well.
219 *
220 * Note that the notifier provides which bits are changed in the state
221 * variable with the val parameter (second) to the callback.
222 */
extcon_update_state(struct extcon_dev * edev,u32 mask,u32 state)223 int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state)
224 {
225 char name_buf[120];
226 char state_buf[120];
227 char *prop_buf;
228 char *envp[3];
229 int env_offset = 0;
230 int length;
231 unsigned long flags;
232
233 spin_lock_irqsave(&edev->lock, flags);
234
235 if (edev->state != ((edev->state & ~mask) | (state & mask))) {
236 u32 old_state = edev->state;
237
238 if (check_mutually_exclusive(edev, (edev->state & ~mask) |
239 (state & mask))) {
240 spin_unlock_irqrestore(&edev->lock, flags);
241 return -EPERM;
242 }
243
244 edev->state &= ~mask;
245 edev->state |= state & mask;
246
247 raw_notifier_call_chain(&edev->nh, old_state, edev);
248
249 /* This could be in interrupt handler */
250 prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
251 if (prop_buf) {
252 length = name_show(edev->dev, NULL, prop_buf);
253 if (length > 0) {
254 if (prop_buf[length - 1] == '\n')
255 prop_buf[length - 1] = 0;
256 snprintf(name_buf, sizeof(name_buf),
257 "NAME=%s", prop_buf);
258 envp[env_offset++] = name_buf;
259 }
260 length = state_show(edev->dev, NULL, prop_buf);
261 if (length > 0) {
262 if (prop_buf[length - 1] == '\n')
263 prop_buf[length - 1] = 0;
264 snprintf(state_buf, sizeof(state_buf),
265 "STATE=%s", prop_buf);
266 envp[env_offset++] = state_buf;
267 }
268 envp[env_offset] = NULL;
269 /* Unlock early before uevent */
270 spin_unlock_irqrestore(&edev->lock, flags);
271
272 kobject_uevent_env(&edev->dev->kobj, KOBJ_CHANGE, envp);
273 free_page((unsigned long)prop_buf);
274 } else {
275 /* Unlock early before uevent */
276 spin_unlock_irqrestore(&edev->lock, flags);
277
278 dev_err(edev->dev, "out of memory in extcon_set_state\n");
279 kobject_uevent(&edev->dev->kobj, KOBJ_CHANGE);
280 }
281 } else {
282 /* No changes */
283 spin_unlock_irqrestore(&edev->lock, flags);
284 }
285
286 return 0;
287 }
288 EXPORT_SYMBOL_GPL(extcon_update_state);
289
290 /**
291 * extcon_set_state() - Set the cable attach states of the extcon device.
292 * @edev: the extcon device
293 * @state: new cable attach status for @edev
294 *
295 * Note that notifier provides which bits are changed in the state
296 * variable with the val parameter (second) to the callback.
297 */
extcon_set_state(struct extcon_dev * edev,u32 state)298 int extcon_set_state(struct extcon_dev *edev, u32 state)
299 {
300 return extcon_update_state(edev, 0xffffffff, state);
301 }
302 EXPORT_SYMBOL_GPL(extcon_set_state);
303
304 /**
305 * extcon_find_cable_index() - Get the cable index based on the cable name.
306 * @edev: the extcon device that has the cable.
307 * @cable_name: cable name to be searched.
308 *
309 * Note that accessing a cable state based on cable_index is faster than
310 * cable_name because using cable_name induces a loop with strncmp().
311 * Thus, when get/set_cable_state is repeatedly used, using cable_index
312 * is recommended.
313 */
extcon_find_cable_index(struct extcon_dev * edev,const char * cable_name)314 int extcon_find_cable_index(struct extcon_dev *edev, const char *cable_name)
315 {
316 int i;
317
318 if (edev->supported_cable) {
319 for (i = 0; edev->supported_cable[i]; i++) {
320 if (!strncmp(edev->supported_cable[i],
321 cable_name, CABLE_NAME_MAX))
322 return i;
323 }
324 }
325
326 return -EINVAL;
327 }
328 EXPORT_SYMBOL_GPL(extcon_find_cable_index);
329
330 /**
331 * extcon_get_cable_state_() - Get the status of a specific cable.
332 * @edev: the extcon device that has the cable.
333 * @index: cable index that can be retrieved by extcon_find_cable_index().
334 */
extcon_get_cable_state_(struct extcon_dev * edev,int index)335 int extcon_get_cable_state_(struct extcon_dev *edev, int index)
336 {
337 if (index < 0 || (edev->max_supported && edev->max_supported <= index))
338 return -EINVAL;
339
340 return !!(edev->state & (1 << index));
341 }
342 EXPORT_SYMBOL_GPL(extcon_get_cable_state_);
343
344 /**
345 * extcon_get_cable_state() - Get the status of a specific cable.
346 * @edev: the extcon device that has the cable.
347 * @cable_name: cable name.
348 *
349 * Note that this is slower than extcon_get_cable_state_.
350 */
extcon_get_cable_state(struct extcon_dev * edev,const char * cable_name)351 int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name)
352 {
353 return extcon_get_cable_state_(edev, extcon_find_cable_index
354 (edev, cable_name));
355 }
356 EXPORT_SYMBOL_GPL(extcon_get_cable_state);
357
358 /**
359 * extcon_set_cable_state_() - Set the status of a specific cable.
360 * @edev: the extcon device that has the cable.
361 * @index: cable index that can be retrieved by extcon_find_cable_index().
362 * @cable_state: the new cable status. The default semantics is
363 * true: attached / false: detached.
364 */
extcon_set_cable_state_(struct extcon_dev * edev,int index,bool cable_state)365 int extcon_set_cable_state_(struct extcon_dev *edev,
366 int index, bool cable_state)
367 {
368 u32 state;
369
370 if (index < 0 || (edev->max_supported && edev->max_supported <= index))
371 return -EINVAL;
372
373 state = cable_state ? (1 << index) : 0;
374 return extcon_update_state(edev, 1 << index, state);
375 }
376 EXPORT_SYMBOL_GPL(extcon_set_cable_state_);
377
378 /**
379 * extcon_set_cable_state() - Set the status of a specific cable.
380 * @edev: the extcon device that has the cable.
381 * @cable_name: cable name.
382 * @cable_state: the new cable status. The default semantics is
383 * true: attached / false: detached.
384 *
385 * Note that this is slower than extcon_set_cable_state_.
386 */
extcon_set_cable_state(struct extcon_dev * edev,const char * cable_name,bool cable_state)387 int extcon_set_cable_state(struct extcon_dev *edev,
388 const char *cable_name, bool cable_state)
389 {
390 return extcon_set_cable_state_(edev, extcon_find_cable_index
391 (edev, cable_name), cable_state);
392 }
393 EXPORT_SYMBOL_GPL(extcon_set_cable_state);
394
395 /**
396 * extcon_get_extcon_dev() - Get the extcon device instance from the name
397 * @extcon_name: The extcon name provided with extcon_dev_register()
398 */
extcon_get_extcon_dev(const char * extcon_name)399 struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
400 {
401 struct extcon_dev *sd;
402
403 mutex_lock(&extcon_dev_list_lock);
404 list_for_each_entry(sd, &extcon_dev_list, entry) {
405 if (!strcmp(sd->name, extcon_name))
406 goto out;
407 }
408 sd = NULL;
409 out:
410 mutex_unlock(&extcon_dev_list_lock);
411 return sd;
412 }
413 EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
414
_call_per_cable(struct notifier_block * nb,unsigned long val,void * ptr)415 static int _call_per_cable(struct notifier_block *nb, unsigned long val,
416 void *ptr)
417 {
418 struct extcon_specific_cable_nb *obj = container_of(nb,
419 struct extcon_specific_cable_nb, internal_nb);
420 struct extcon_dev *edev = ptr;
421
422 if ((val & (1 << obj->cable_index)) !=
423 (edev->state & (1 << obj->cable_index))) {
424 bool cable_state = true;
425
426 obj->previous_value = val;
427
428 if (val & (1 << obj->cable_index))
429 cable_state = false;
430
431 return obj->user_nb->notifier_call(obj->user_nb,
432 cable_state, ptr);
433 }
434
435 return NOTIFY_OK;
436 }
437
438 /**
439 * extcon_register_interest() - Register a notifier for a state change of a
440 * specific cable, not an entier set of cables of a
441 * extcon device.
442 * @obj: an empty extcon_specific_cable_nb object to be returned.
443 * @extcon_name: the name of extcon device.
444 * if NULL, extcon_register_interest will register
445 * every cable with the target cable_name given.
446 * @cable_name: the target cable name.
447 * @nb: the notifier block to get notified.
448 *
449 * Provide an empty extcon_specific_cable_nb. extcon_register_interest() sets
450 * the struct for you.
451 *
452 * extcon_register_interest is a helper function for those who want to get
453 * notification for a single specific cable's status change. If a user wants
454 * to get notification for any changes of all cables of a extcon device,
455 * he/she should use the general extcon_register_notifier().
456 *
457 * Note that the second parameter given to the callback of nb (val) is
458 * "old_state", not the current state. The current state can be retrieved
459 * by looking at the third pameter (edev pointer)'s state value.
460 */
extcon_register_interest(struct extcon_specific_cable_nb * obj,const char * extcon_name,const char * cable_name,struct notifier_block * nb)461 int extcon_register_interest(struct extcon_specific_cable_nb *obj,
462 const char *extcon_name, const char *cable_name,
463 struct notifier_block *nb)
464 {
465 if (!obj || !cable_name || !nb)
466 return -EINVAL;
467
468 if (extcon_name) {
469 obj->edev = extcon_get_extcon_dev(extcon_name);
470 if (!obj->edev)
471 return -ENODEV;
472
473 obj->cable_index = extcon_find_cable_index(obj->edev, cable_name);
474 if (obj->cable_index < 0)
475 return obj->cable_index;
476
477 obj->user_nb = nb;
478
479 obj->internal_nb.notifier_call = _call_per_cable;
480
481 return raw_notifier_chain_register(&obj->edev->nh, &obj->internal_nb);
482 } else {
483 struct class_dev_iter iter;
484 struct extcon_dev *extd;
485 struct device *dev;
486
487 if (!extcon_class)
488 return -ENODEV;
489 class_dev_iter_init(&iter, extcon_class, NULL, NULL);
490 while ((dev = class_dev_iter_next(&iter))) {
491 extd = (struct extcon_dev *)dev_get_drvdata(dev);
492
493 if (extcon_find_cable_index(extd, cable_name) < 0)
494 continue;
495
496 class_dev_iter_exit(&iter);
497 return extcon_register_interest(obj, extd->name,
498 cable_name, nb);
499 }
500
501 return -ENODEV;
502 }
503 }
504
505 /**
506 * extcon_unregister_interest() - Unregister the notifier registered by
507 * extcon_register_interest().
508 * @obj: the extcon_specific_cable_nb object returned by
509 * extcon_register_interest().
510 */
extcon_unregister_interest(struct extcon_specific_cable_nb * obj)511 int extcon_unregister_interest(struct extcon_specific_cable_nb *obj)
512 {
513 if (!obj)
514 return -EINVAL;
515
516 return raw_notifier_chain_unregister(&obj->edev->nh, &obj->internal_nb);
517 }
518
519 /**
520 * extcon_register_notifier() - Register a notifiee to get notified by
521 * any attach status changes from the extcon.
522 * @edev: the extcon device.
523 * @nb: a notifier block to be registered.
524 *
525 * Note that the second parameter given to the callback of nb (val) is
526 * "old_state", not the current state. The current state can be retrieved
527 * by looking at the third pameter (edev pointer)'s state value.
528 */
extcon_register_notifier(struct extcon_dev * edev,struct notifier_block * nb)529 int extcon_register_notifier(struct extcon_dev *edev,
530 struct notifier_block *nb)
531 {
532 return raw_notifier_chain_register(&edev->nh, nb);
533 }
534 EXPORT_SYMBOL_GPL(extcon_register_notifier);
535
536 /**
537 * extcon_unregister_notifier() - Unregister a notifiee from the extcon device.
538 * @edev: the extcon device.
539 * @nb: a registered notifier block to be unregistered.
540 */
extcon_unregister_notifier(struct extcon_dev * edev,struct notifier_block * nb)541 int extcon_unregister_notifier(struct extcon_dev *edev,
542 struct notifier_block *nb)
543 {
544 return raw_notifier_chain_unregister(&edev->nh, nb);
545 }
546 EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
547
548 static struct device_attribute extcon_attrs[] = {
549 __ATTR(state, S_IRUGO | S_IWUSR, state_show, state_store),
550 __ATTR_RO(name),
551 __ATTR_NULL,
552 };
553
create_extcon_class(void)554 static int create_extcon_class(void)
555 {
556 if (!extcon_class) {
557 extcon_class = class_create(THIS_MODULE, "extcon");
558 if (IS_ERR(extcon_class))
559 return PTR_ERR(extcon_class);
560 extcon_class->dev_attrs = extcon_attrs;
561
562 #if defined(CONFIG_ANDROID)
563 switch_class = class_compat_register("switch");
564 if (WARN(!switch_class, "cannot allocate"))
565 return -ENOMEM;
566 #endif /* CONFIG_ANDROID */
567 }
568
569 return 0;
570 }
571
extcon_dev_release(struct device * dev)572 static void extcon_dev_release(struct device *dev)
573 {
574 kfree(dev);
575 }
576
577 static const char *muex_name = "mutually_exclusive";
dummy_sysfs_dev_release(struct device * dev)578 static void dummy_sysfs_dev_release(struct device *dev)
579 {
580 }
581
582 /**
583 * extcon_dev_register() - Register a new extcon device
584 * @edev : the new extcon device (should be allocated before calling)
585 * @dev : the parent device for this extcon device.
586 *
587 * Among the members of edev struct, please set the "user initializing data"
588 * in any case and set the "optional callbacks" if required. However, please
589 * do not set the values of "internal data", which are initialized by
590 * this function.
591 */
extcon_dev_register(struct extcon_dev * edev,struct device * dev)592 int extcon_dev_register(struct extcon_dev *edev, struct device *dev)
593 {
594 int ret, index = 0;
595
596 if (!extcon_class) {
597 ret = create_extcon_class();
598 if (ret < 0)
599 return ret;
600 }
601
602 if (edev->supported_cable) {
603 /* Get size of array */
604 for (index = 0; edev->supported_cable[index]; index++)
605 ;
606 edev->max_supported = index;
607 } else {
608 edev->max_supported = 0;
609 }
610
611 if (index > SUPPORTED_CABLE_MAX) {
612 dev_err(edev->dev, "extcon: maximum number of supported cables exceeded.\n");
613 return -EINVAL;
614 }
615
616 edev->dev = kzalloc(sizeof(struct device), GFP_KERNEL);
617 if (!edev->dev)
618 return -ENOMEM;
619 edev->dev->parent = dev;
620 edev->dev->class = extcon_class;
621 edev->dev->release = extcon_dev_release;
622
623 dev_set_name(edev->dev, edev->name ? edev->name : dev_name(dev));
624
625 if (edev->max_supported) {
626 char buf[10];
627 char *str;
628 struct extcon_cable *cable;
629
630 edev->cables = kzalloc(sizeof(struct extcon_cable) *
631 edev->max_supported, GFP_KERNEL);
632 if (!edev->cables) {
633 ret = -ENOMEM;
634 goto err_sysfs_alloc;
635 }
636 for (index = 0; index < edev->max_supported; index++) {
637 cable = &edev->cables[index];
638
639 snprintf(buf, 10, "cable.%d", index);
640 str = kzalloc(sizeof(char) * (strlen(buf) + 1),
641 GFP_KERNEL);
642 if (!str) {
643 for (index--; index >= 0; index--) {
644 cable = &edev->cables[index];
645 kfree(cable->attr_g.name);
646 }
647 ret = -ENOMEM;
648
649 goto err_alloc_cables;
650 }
651 strcpy(str, buf);
652
653 cable->edev = edev;
654 cable->cable_index = index;
655 cable->attrs[0] = &cable->attr_name.attr;
656 cable->attrs[1] = &cable->attr_state.attr;
657 cable->attrs[2] = NULL;
658 cable->attr_g.name = str;
659 cable->attr_g.attrs = cable->attrs;
660
661 sysfs_attr_init(&cable->attr_name.attr);
662 cable->attr_name.attr.name = "name";
663 cable->attr_name.attr.mode = 0444;
664 cable->attr_name.show = cable_name_show;
665
666 sysfs_attr_init(&cable->attr_state.attr);
667 cable->attr_state.attr.name = "state";
668 cable->attr_state.attr.mode = 0644;
669 cable->attr_state.show = cable_state_show;
670 cable->attr_state.store = cable_state_store;
671 }
672 }
673
674 if (edev->max_supported && edev->mutually_exclusive) {
675 char buf[80];
676 char *name;
677
678 /* Count the size of mutually_exclusive array */
679 for (index = 0; edev->mutually_exclusive[index]; index++)
680 ;
681
682 edev->attrs_muex = kzalloc(sizeof(struct attribute *) *
683 (index + 1), GFP_KERNEL);
684 if (!edev->attrs_muex) {
685 ret = -ENOMEM;
686 goto err_muex;
687 }
688
689 edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) *
690 index, GFP_KERNEL);
691 if (!edev->d_attrs_muex) {
692 ret = -ENOMEM;
693 kfree(edev->attrs_muex);
694 goto err_muex;
695 }
696
697 for (index = 0; edev->mutually_exclusive[index]; index++) {
698 sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
699 name = kzalloc(sizeof(char) * (strlen(buf) + 1),
700 GFP_KERNEL);
701 if (!name) {
702 for (index--; index >= 0; index--) {
703 kfree(edev->d_attrs_muex[index].attr.
704 name);
705 }
706 kfree(edev->d_attrs_muex);
707 kfree(edev->attrs_muex);
708 ret = -ENOMEM;
709 goto err_muex;
710 }
711 strcpy(name, buf);
712 sysfs_attr_init(&edev->d_attrs_muex[index].attr);
713 edev->d_attrs_muex[index].attr.name = name;
714 edev->d_attrs_muex[index].attr.mode = 0000;
715 edev->attrs_muex[index] = &edev->d_attrs_muex[index]
716 .attr;
717 }
718 edev->attr_g_muex.name = muex_name;
719 edev->attr_g_muex.attrs = edev->attrs_muex;
720
721 }
722
723 if (edev->max_supported) {
724 edev->extcon_dev_type.groups =
725 kzalloc(sizeof(struct attribute_group *) *
726 (edev->max_supported + 2), GFP_KERNEL);
727 if (!edev->extcon_dev_type.groups) {
728 ret = -ENOMEM;
729 goto err_alloc_groups;
730 }
731
732 edev->extcon_dev_type.name = dev_name(edev->dev);
733 edev->extcon_dev_type.release = dummy_sysfs_dev_release;
734
735 for (index = 0; index < edev->max_supported; index++)
736 edev->extcon_dev_type.groups[index] =
737 &edev->cables[index].attr_g;
738 if (edev->mutually_exclusive)
739 edev->extcon_dev_type.groups[index] =
740 &edev->attr_g_muex;
741
742 edev->dev->type = &edev->extcon_dev_type;
743 }
744
745 ret = device_register(edev->dev);
746 if (ret) {
747 put_device(edev->dev);
748 goto err_dev;
749 }
750 #if defined(CONFIG_ANDROID)
751 if (switch_class)
752 ret = class_compat_create_link(switch_class, edev->dev,
753 NULL);
754 #endif /* CONFIG_ANDROID */
755
756 spin_lock_init(&edev->lock);
757
758 RAW_INIT_NOTIFIER_HEAD(&edev->nh);
759
760 dev_set_drvdata(edev->dev, edev);
761 edev->state = 0;
762
763 mutex_lock(&extcon_dev_list_lock);
764 list_add(&edev->entry, &extcon_dev_list);
765 mutex_unlock(&extcon_dev_list_lock);
766
767 return 0;
768
769 err_dev:
770 if (edev->max_supported)
771 kfree(edev->extcon_dev_type.groups);
772 err_alloc_groups:
773 if (edev->max_supported && edev->mutually_exclusive) {
774 for (index = 0; edev->mutually_exclusive[index]; index++)
775 kfree(edev->d_attrs_muex[index].attr.name);
776 kfree(edev->d_attrs_muex);
777 kfree(edev->attrs_muex);
778 }
779 err_muex:
780 for (index = 0; index < edev->max_supported; index++)
781 kfree(edev->cables[index].attr_g.name);
782 err_alloc_cables:
783 if (edev->max_supported)
784 kfree(edev->cables);
785 err_sysfs_alloc:
786 kfree(edev->dev);
787 return ret;
788 }
789 EXPORT_SYMBOL_GPL(extcon_dev_register);
790
791 /**
792 * extcon_dev_unregister() - Unregister the extcon device.
793 * @edev: the extcon device instance to be unregistered.
794 *
795 * Note that this does not call kfree(edev) because edev was not allocated
796 * by this class.
797 */
extcon_dev_unregister(struct extcon_dev * edev)798 void extcon_dev_unregister(struct extcon_dev *edev)
799 {
800 int index;
801
802 mutex_lock(&extcon_dev_list_lock);
803 list_del(&edev->entry);
804 mutex_unlock(&extcon_dev_list_lock);
805
806 if (IS_ERR_OR_NULL(get_device(edev->dev))) {
807 dev_err(edev->dev, "Failed to unregister extcon_dev (%s)\n",
808 dev_name(edev->dev));
809 return;
810 }
811
812 if (edev->mutually_exclusive && edev->max_supported) {
813 for (index = 0; edev->mutually_exclusive[index];
814 index++)
815 kfree(edev->d_attrs_muex[index].attr.name);
816 kfree(edev->d_attrs_muex);
817 kfree(edev->attrs_muex);
818 }
819
820 for (index = 0; index < edev->max_supported; index++)
821 kfree(edev->cables[index].attr_g.name);
822
823 if (edev->max_supported) {
824 kfree(edev->extcon_dev_type.groups);
825 kfree(edev->cables);
826 }
827
828 #if defined(CONFIG_ANDROID)
829 if (switch_class)
830 class_compat_remove_link(switch_class, edev->dev, NULL);
831 #endif
832 device_unregister(edev->dev);
833 put_device(edev->dev);
834 }
835 EXPORT_SYMBOL_GPL(extcon_dev_unregister);
836
extcon_class_init(void)837 static int __init extcon_class_init(void)
838 {
839 return create_extcon_class();
840 }
841 module_init(extcon_class_init);
842
extcon_class_exit(void)843 static void __exit extcon_class_exit(void)
844 {
845 #if defined(CONFIG_ANDROID)
846 class_compat_unregister(switch_class);
847 #endif
848 class_destroy(extcon_class);
849 }
850 module_exit(extcon_class_exit);
851
852 MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
853 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
854 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
855 MODULE_DESCRIPTION("External connector (extcon) class driver");
856 MODULE_LICENSE("GPL");
857