1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
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
37
38
39
40
41
42
43
44const 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
67static struct class *extcon_class;
68#if defined(CONFIG_ANDROID)
69static struct class_compat *switch_class;
70#endif
71
72static LIST_HEAD(extcon_dev_list);
73static DEFINE_MUTEX(extcon_dev_list_lock);
74
75
76
77
78
79
80
81
82
83
84static 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
96 weight = hweight32(correspondants);
97 if (weight > 1)
98 return i + 1;
99 }
100
101 return 0;
102}
103
104static 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 = 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
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
132static ssize_t state_store(struct device *dev, struct device_attribute *attr,
133 const char *buf, size_t count)
134{
135 u32 state;
136 ssize_t ret = 0;
137 struct extcon_dev *edev = dev_get_drvdata(dev);
138
139 ret = sscanf(buf, "0x%x", &state);
140 if (ret == 0)
141 ret = -EINVAL;
142 else
143 ret = extcon_set_state(edev, state);
144
145 if (ret < 0)
146 return ret;
147
148 return count;
149}
150static DEVICE_ATTR_RW(state);
151
152static ssize_t name_show(struct device *dev, struct device_attribute *attr,
153 char *buf)
154{
155 struct extcon_dev *edev = dev_get_drvdata(dev);
156
157
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}
166static DEVICE_ATTR_RO(name);
167
168static ssize_t cable_name_show(struct device *dev,
169 struct device_attribute *attr, char *buf)
170{
171 struct extcon_cable *cable = container_of(attr, struct extcon_cable,
172 attr_name);
173
174 return sprintf(buf, "%s\n",
175 cable->edev->supported_cable[cable->cable_index]);
176}
177
178static ssize_t cable_state_show(struct device *dev,
179 struct device_attribute *attr, char *buf)
180{
181 struct extcon_cable *cable = container_of(attr, struct extcon_cable,
182 attr_state);
183
184 return sprintf(buf, "%d\n",
185 extcon_get_cable_state_(cable->edev,
186 cable->cable_index));
187}
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state)
205{
206 char name_buf[120];
207 char state_buf[120];
208 char *prop_buf;
209 char *envp[3];
210 int env_offset = 0;
211 int length;
212 unsigned long flags;
213
214 spin_lock_irqsave(&edev->lock, flags);
215
216 if (edev->state != ((edev->state & ~mask) | (state & mask))) {
217 u32 old_state = edev->state;
218
219 if (check_mutually_exclusive(edev, (edev->state & ~mask) |
220 (state & mask))) {
221 spin_unlock_irqrestore(&edev->lock, flags);
222 return -EPERM;
223 }
224
225 edev->state &= ~mask;
226 edev->state |= state & mask;
227
228 raw_notifier_call_chain(&edev->nh, old_state, edev);
229
230 prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
231 if (prop_buf) {
232 length = name_show(&edev->dev, NULL, prop_buf);
233 if (length > 0) {
234 if (prop_buf[length - 1] == '\n')
235 prop_buf[length - 1] = 0;
236 snprintf(name_buf, sizeof(name_buf),
237 "NAME=%s", prop_buf);
238 envp[env_offset++] = name_buf;
239 }
240 length = state_show(&edev->dev, NULL, prop_buf);
241 if (length > 0) {
242 if (prop_buf[length - 1] == '\n')
243 prop_buf[length - 1] = 0;
244 snprintf(state_buf, sizeof(state_buf),
245 "STATE=%s", prop_buf);
246 envp[env_offset++] = state_buf;
247 }
248 envp[env_offset] = NULL;
249
250 spin_unlock_irqrestore(&edev->lock, flags);
251
252 kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp);
253 free_page((unsigned long)prop_buf);
254 } else {
255
256 spin_unlock_irqrestore(&edev->lock, flags);
257
258 dev_err(&edev->dev, "out of memory in extcon_set_state\n");
259 kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE);
260 }
261 } else {
262
263 spin_unlock_irqrestore(&edev->lock, flags);
264 }
265
266 return 0;
267}
268EXPORT_SYMBOL_GPL(extcon_update_state);
269
270
271
272
273
274
275
276
277
278int extcon_set_state(struct extcon_dev *edev, u32 state)
279{
280 return extcon_update_state(edev, 0xffffffff, state);
281}
282EXPORT_SYMBOL_GPL(extcon_set_state);
283
284
285
286
287
288
289
290
291
292
293
294int extcon_find_cable_index(struct extcon_dev *edev, const char *cable_name)
295{
296 int i;
297
298 if (edev->supported_cable) {
299 for (i = 0; edev->supported_cable[i]; i++) {
300 if (!strncmp(edev->supported_cable[i],
301 cable_name, CABLE_NAME_MAX))
302 return i;
303 }
304 }
305
306 return -EINVAL;
307}
308EXPORT_SYMBOL_GPL(extcon_find_cable_index);
309
310
311
312
313
314
315int extcon_get_cable_state_(struct extcon_dev *edev, int index)
316{
317 if (index < 0 || (edev->max_supported && edev->max_supported <= index))
318 return -EINVAL;
319
320 return !!(edev->state & (1 << index));
321}
322EXPORT_SYMBOL_GPL(extcon_get_cable_state_);
323
324
325
326
327
328
329
330
331int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name)
332{
333 return extcon_get_cable_state_(edev, extcon_find_cable_index
334 (edev, cable_name));
335}
336EXPORT_SYMBOL_GPL(extcon_get_cable_state);
337
338
339
340
341
342
343
344
345
346int extcon_set_cable_state_(struct extcon_dev *edev,
347 int index, bool cable_state)
348{
349 u32 state;
350
351 if (index < 0 || (edev->max_supported && edev->max_supported <= index))
352 return -EINVAL;
353
354 state = cable_state ? (1 << index) : 0;
355 return extcon_update_state(edev, 1 << index, state);
356}
357EXPORT_SYMBOL_GPL(extcon_set_cable_state_);
358
359
360
361
362
363
364
365
366
367
368int extcon_set_cable_state(struct extcon_dev *edev,
369 const char *cable_name, bool cable_state)
370{
371 return extcon_set_cable_state_(edev, extcon_find_cable_index
372 (edev, cable_name), cable_state);
373}
374EXPORT_SYMBOL_GPL(extcon_set_cable_state);
375
376
377
378
379
380struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
381{
382 struct extcon_dev *sd;
383
384 mutex_lock(&extcon_dev_list_lock);
385 list_for_each_entry(sd, &extcon_dev_list, entry) {
386 if (!strcmp(sd->name, extcon_name))
387 goto out;
388 }
389 sd = NULL;
390out:
391 mutex_unlock(&extcon_dev_list_lock);
392 return sd;
393}
394EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
395
396static int _call_per_cable(struct notifier_block *nb, unsigned long val,
397 void *ptr)
398{
399 struct extcon_specific_cable_nb *obj = container_of(nb,
400 struct extcon_specific_cable_nb, internal_nb);
401 struct extcon_dev *edev = ptr;
402
403 if ((val & (1 << obj->cable_index)) !=
404 (edev->state & (1 << obj->cable_index))) {
405 bool cable_state = true;
406
407 obj->previous_value = val;
408
409 if (val & (1 << obj->cable_index))
410 cable_state = false;
411
412 return obj->user_nb->notifier_call(obj->user_nb,
413 cable_state, ptr);
414 }
415
416 return NOTIFY_OK;
417}
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442int extcon_register_interest(struct extcon_specific_cable_nb *obj,
443 const char *extcon_name, const char *cable_name,
444 struct notifier_block *nb)
445{
446 if (!obj || !cable_name || !nb)
447 return -EINVAL;
448
449 if (extcon_name) {
450 obj->edev = extcon_get_extcon_dev(extcon_name);
451 if (!obj->edev)
452 return -ENODEV;
453
454 obj->cable_index = extcon_find_cable_index(obj->edev,
455 cable_name);
456 if (obj->cable_index < 0)
457 return obj->cable_index;
458
459 obj->user_nb = nb;
460
461 obj->internal_nb.notifier_call = _call_per_cable;
462
463 return raw_notifier_chain_register(&obj->edev->nh,
464 &obj->internal_nb);
465 } else {
466 struct class_dev_iter iter;
467 struct extcon_dev *extd;
468 struct device *dev;
469
470 if (!extcon_class)
471 return -ENODEV;
472 class_dev_iter_init(&iter, extcon_class, NULL, NULL);
473 while ((dev = class_dev_iter_next(&iter))) {
474 extd = dev_get_drvdata(dev);
475
476 if (extcon_find_cable_index(extd, cable_name) < 0)
477 continue;
478
479 class_dev_iter_exit(&iter);
480 return extcon_register_interest(obj, extd->name,
481 cable_name, nb);
482 }
483
484 return -ENODEV;
485 }
486}
487EXPORT_SYMBOL_GPL(extcon_register_interest);
488
489
490
491
492
493
494
495int extcon_unregister_interest(struct extcon_specific_cable_nb *obj)
496{
497 if (!obj)
498 return -EINVAL;
499
500 return raw_notifier_chain_unregister(&obj->edev->nh, &obj->internal_nb);
501}
502EXPORT_SYMBOL_GPL(extcon_unregister_interest);
503
504
505
506
507
508
509
510
511
512
513
514int extcon_register_notifier(struct extcon_dev *edev,
515 struct notifier_block *nb)
516{
517 return raw_notifier_chain_register(&edev->nh, nb);
518}
519EXPORT_SYMBOL_GPL(extcon_register_notifier);
520
521
522
523
524
525
526int extcon_unregister_notifier(struct extcon_dev *edev,
527 struct notifier_block *nb)
528{
529 return raw_notifier_chain_unregister(&edev->nh, nb);
530}
531EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
532
533static struct attribute *extcon_attrs[] = {
534 &dev_attr_state.attr,
535 &dev_attr_name.attr,
536 NULL,
537};
538ATTRIBUTE_GROUPS(extcon);
539
540static int create_extcon_class(void)
541{
542 if (!extcon_class) {
543 extcon_class = class_create(THIS_MODULE, "extcon");
544 if (IS_ERR(extcon_class))
545 return PTR_ERR(extcon_class);
546 extcon_class->dev_groups = extcon_groups;
547
548#if defined(CONFIG_ANDROID)
549 switch_class = class_compat_register("switch");
550 if (WARN(!switch_class, "cannot allocate"))
551 return -ENOMEM;
552#endif
553 }
554
555 return 0;
556}
557
558static void extcon_dev_release(struct device *dev)
559{
560}
561
562static const char *muex_name = "mutually_exclusive";
563static void dummy_sysfs_dev_release(struct device *dev)
564{
565}
566
567
568
569
570
571
572
573
574
575
576int extcon_dev_register(struct extcon_dev *edev)
577{
578 int ret, index = 0;
579
580 if (!extcon_class) {
581 ret = create_extcon_class();
582 if (ret < 0)
583 return ret;
584 }
585
586 if (edev->supported_cable) {
587
588 for (index = 0; edev->supported_cable[index]; index++)
589 ;
590 edev->max_supported = index;
591 } else {
592 edev->max_supported = 0;
593 }
594
595 if (index > SUPPORTED_CABLE_MAX) {
596 dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
597 return -EINVAL;
598 }
599
600 edev->dev.class = extcon_class;
601 edev->dev.release = extcon_dev_release;
602
603 edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
604 if (IS_ERR_OR_NULL(edev->name)) {
605 dev_err(&edev->dev,
606 "extcon device name is null\n");
607 return -EINVAL;
608 }
609 dev_set_name(&edev->dev, "%s", edev->name);
610
611 if (edev->max_supported) {
612 char buf[10];
613 char *str;
614 struct extcon_cable *cable;
615
616 edev->cables = kzalloc(sizeof(struct extcon_cable) *
617 edev->max_supported, GFP_KERNEL);
618 if (!edev->cables) {
619 ret = -ENOMEM;
620 goto err_sysfs_alloc;
621 }
622 for (index = 0; index < edev->max_supported; index++) {
623 cable = &edev->cables[index];
624
625 snprintf(buf, 10, "cable.%d", index);
626 str = kzalloc(sizeof(char) * (strlen(buf) + 1),
627 GFP_KERNEL);
628 if (!str) {
629 for (index--; index >= 0; index--) {
630 cable = &edev->cables[index];
631 kfree(cable->attr_g.name);
632 }
633 ret = -ENOMEM;
634
635 goto err_alloc_cables;
636 }
637 strcpy(str, buf);
638
639 cable->edev = edev;
640 cable->cable_index = index;
641 cable->attrs[0] = &cable->attr_name.attr;
642 cable->attrs[1] = &cable->attr_state.attr;
643 cable->attrs[2] = NULL;
644 cable->attr_g.name = str;
645 cable->attr_g.attrs = cable->attrs;
646
647 sysfs_attr_init(&cable->attr_name.attr);
648 cable->attr_name.attr.name = "name";
649 cable->attr_name.attr.mode = 0444;
650 cable->attr_name.show = cable_name_show;
651
652 sysfs_attr_init(&cable->attr_state.attr);
653 cable->attr_state.attr.name = "state";
654 cable->attr_state.attr.mode = 0444;
655 cable->attr_state.show = cable_state_show;
656 }
657 }
658
659 if (edev->max_supported && edev->mutually_exclusive) {
660 char buf[80];
661 char *name;
662
663
664 for (index = 0; edev->mutually_exclusive[index]; index++)
665 ;
666
667 edev->attrs_muex = kzalloc(sizeof(struct attribute *) *
668 (index + 1), GFP_KERNEL);
669 if (!edev->attrs_muex) {
670 ret = -ENOMEM;
671 goto err_muex;
672 }
673
674 edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) *
675 index, GFP_KERNEL);
676 if (!edev->d_attrs_muex) {
677 ret = -ENOMEM;
678 kfree(edev->attrs_muex);
679 goto err_muex;
680 }
681
682 for (index = 0; edev->mutually_exclusive[index]; index++) {
683 sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
684 name = kzalloc(sizeof(char) * (strlen(buf) + 1),
685 GFP_KERNEL);
686 if (!name) {
687 for (index--; index >= 0; index--) {
688 kfree(edev->d_attrs_muex[index].attr.
689 name);
690 }
691 kfree(edev->d_attrs_muex);
692 kfree(edev->attrs_muex);
693 ret = -ENOMEM;
694 goto err_muex;
695 }
696 strcpy(name, buf);
697 sysfs_attr_init(&edev->d_attrs_muex[index].attr);
698 edev->d_attrs_muex[index].attr.name = name;
699 edev->d_attrs_muex[index].attr.mode = 0000;
700 edev->attrs_muex[index] = &edev->d_attrs_muex[index]
701 .attr;
702 }
703 edev->attr_g_muex.name = muex_name;
704 edev->attr_g_muex.attrs = edev->attrs_muex;
705
706 }
707
708 if (edev->max_supported) {
709 edev->extcon_dev_type.groups =
710 kzalloc(sizeof(struct attribute_group *) *
711 (edev->max_supported + 2), GFP_KERNEL);
712 if (!edev->extcon_dev_type.groups) {
713 ret = -ENOMEM;
714 goto err_alloc_groups;
715 }
716
717 edev->extcon_dev_type.name = dev_name(&edev->dev);
718 edev->extcon_dev_type.release = dummy_sysfs_dev_release;
719
720 for (index = 0; index < edev->max_supported; index++)
721 edev->extcon_dev_type.groups[index] =
722 &edev->cables[index].attr_g;
723 if (edev->mutually_exclusive)
724 edev->extcon_dev_type.groups[index] =
725 &edev->attr_g_muex;
726
727 edev->dev.type = &edev->extcon_dev_type;
728 }
729
730 ret = device_register(&edev->dev);
731 if (ret) {
732 put_device(&edev->dev);
733 goto err_dev;
734 }
735#if defined(CONFIG_ANDROID)
736 if (switch_class)
737 ret = class_compat_create_link(switch_class, &edev->dev, NULL);
738#endif
739
740 spin_lock_init(&edev->lock);
741
742 RAW_INIT_NOTIFIER_HEAD(&edev->nh);
743
744 dev_set_drvdata(&edev->dev, edev);
745 edev->state = 0;
746
747 mutex_lock(&extcon_dev_list_lock);
748 list_add(&edev->entry, &extcon_dev_list);
749 mutex_unlock(&extcon_dev_list_lock);
750
751 return 0;
752
753err_dev:
754 if (edev->max_supported)
755 kfree(edev->extcon_dev_type.groups);
756err_alloc_groups:
757 if (edev->max_supported && edev->mutually_exclusive) {
758 for (index = 0; edev->mutually_exclusive[index]; index++)
759 kfree(edev->d_attrs_muex[index].attr.name);
760 kfree(edev->d_attrs_muex);
761 kfree(edev->attrs_muex);
762 }
763err_muex:
764 for (index = 0; index < edev->max_supported; index++)
765 kfree(edev->cables[index].attr_g.name);
766err_alloc_cables:
767 if (edev->max_supported)
768 kfree(edev->cables);
769err_sysfs_alloc:
770 return ret;
771}
772EXPORT_SYMBOL_GPL(extcon_dev_register);
773
774
775
776
777
778
779
780
781void extcon_dev_unregister(struct extcon_dev *edev)
782{
783 int index;
784
785 mutex_lock(&extcon_dev_list_lock);
786 list_del(&edev->entry);
787 mutex_unlock(&extcon_dev_list_lock);
788
789 if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
790 dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
791 dev_name(&edev->dev));
792 return;
793 }
794
795 device_unregister(&edev->dev);
796
797 if (edev->mutually_exclusive && edev->max_supported) {
798 for (index = 0; edev->mutually_exclusive[index];
799 index++)
800 kfree(edev->d_attrs_muex[index].attr.name);
801 kfree(edev->d_attrs_muex);
802 kfree(edev->attrs_muex);
803 }
804
805 for (index = 0; index < edev->max_supported; index++)
806 kfree(edev->cables[index].attr_g.name);
807
808 if (edev->max_supported) {
809 kfree(edev->extcon_dev_type.groups);
810 kfree(edev->cables);
811 }
812
813#if defined(CONFIG_ANDROID)
814 if (switch_class)
815 class_compat_remove_link(switch_class, &edev->dev, NULL);
816#endif
817 put_device(&edev->dev);
818}
819EXPORT_SYMBOL_GPL(extcon_dev_unregister);
820
821static int __init extcon_class_init(void)
822{
823 return create_extcon_class();
824}
825module_init(extcon_class_init);
826
827static void __exit extcon_class_exit(void)
828{
829#if defined(CONFIG_ANDROID)
830 class_compat_unregister(switch_class);
831#endif
832 class_destroy(extcon_class);
833}
834module_exit(extcon_class_exit);
835
836MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
837MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
838MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
839MODULE_DESCRIPTION("External connector (extcon) class driver");
840MODULE_LICENSE("GPL");
841