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-rw-r--r--drivers/extcon/extcon.c1038
1 files changed, 1038 insertions, 0 deletions
diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c
new file mode 100644
index 000000000000..8319f25b7145
--- /dev/null
+++ b/drivers/extcon/extcon.c
@@ -0,0 +1,1038 @@
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/of.h>
33#include <linux/slab.h>
34#include <linux/sysfs.h>
35
36/*
37 * extcon_cable_name suggests the standard cable names for commonly used
38 * cable types.
39 *
40 * However, please do not use extcon_cable_name directly for extcon_dev
41 * struct's supported_cable pointer unless your device really supports
42 * every single port-type of the following cable names. Please choose cable
43 * names that are actually used in your extcon device.
44 */
45const char extcon_cable_name[][CABLE_NAME_MAX + 1] = {
46 [EXTCON_USB] = "USB",
47 [EXTCON_USB_HOST] = "USB-Host",
48 [EXTCON_TA] = "TA",
49 [EXTCON_FAST_CHARGER] = "Fast-charger",
50 [EXTCON_SLOW_CHARGER] = "Slow-charger",
51 [EXTCON_CHARGE_DOWNSTREAM] = "Charge-downstream",
52 [EXTCON_HDMI] = "HDMI",
53 [EXTCON_MHL] = "MHL",
54 [EXTCON_DVI] = "DVI",
55 [EXTCON_VGA] = "VGA",
56 [EXTCON_DOCK] = "Dock",
57 [EXTCON_LINE_IN] = "Line-in",
58 [EXTCON_LINE_OUT] = "Line-out",
59 [EXTCON_MIC_IN] = "Microphone",
60 [EXTCON_HEADPHONE_OUT] = "Headphone",
61 [EXTCON_SPDIF_IN] = "SPDIF-in",
62 [EXTCON_SPDIF_OUT] = "SPDIF-out",
63 [EXTCON_VIDEO_IN] = "Video-in",
64 [EXTCON_VIDEO_OUT] = "Video-out",
65 [EXTCON_MECHANICAL] = "Mechanical",
66};
67
68static struct class *extcon_class;
69#if defined(CONFIG_ANDROID)
70static struct class_compat *switch_class;
71#endif /* CONFIG_ANDROID */
72
73static LIST_HEAD(extcon_dev_list);
74static DEFINE_MUTEX(extcon_dev_list_lock);
75
76/**
77 * check_mutually_exclusive - Check if new_state violates mutually_exclusive
78 * condition.
79 * @edev: the extcon device
80 * @new_state: new cable attach status for @edev
81 *
82 * Returns 0 if nothing violates. Returns the index + 1 for the first
83 * violated condition.
84 */
85static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state)
86{
87 int i = 0;
88
89 if (!edev->mutually_exclusive)
90 return 0;
91
92 for (i = 0; edev->mutually_exclusive[i]; i++) {
93 int weight;
94 u32 correspondants = new_state & edev->mutually_exclusive[i];
95
96 /* calculate the total number of bits set */
97 weight = hweight32(correspondants);
98 if (weight > 1)
99 return i + 1;
100 }
101
102 return 0;
103}
104
105static ssize_t state_show(struct device *dev, struct device_attribute *attr,
106 char *buf)
107{
108 int i, count = 0;
109 struct extcon_dev *edev = dev_get_drvdata(dev);
110
111 if (edev->print_state) {
112 int ret = edev->print_state(edev, buf);
113
114 if (ret >= 0)
115 return ret;
116 /* Use default if failed */
117 }
118
119 if (edev->max_supported == 0)
120 return sprintf(buf, "%u\n", edev->state);
121
122 for (i = 0; i < SUPPORTED_CABLE_MAX; i++) {
123 if (!edev->supported_cable[i])
124 break;
125 count += sprintf(buf + count, "%s=%d\n",
126 edev->supported_cable[i],
127 !!(edev->state & (1 << i)));
128 }
129
130 return count;
131}
132
133static 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 = 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}
151static DEVICE_ATTR_RW(state);
152
153static ssize_t name_show(struct device *dev, struct device_attribute *attr,
154 char *buf)
155{
156 struct extcon_dev *edev = dev_get_drvdata(dev);
157
158 /* Optional callback given by the user */
159 if (edev->print_name) {
160 int ret = edev->print_name(edev, buf);
161 if (ret >= 0)
162 return ret;
163 }
164
165 return sprintf(buf, "%s\n", dev_name(&edev->dev));
166}
167static DEVICE_ATTR_RO(name);
168
169static ssize_t cable_name_show(struct device *dev,
170 struct device_attribute *attr, char *buf)
171{
172 struct extcon_cable *cable = container_of(attr, struct extcon_cable,
173 attr_name);
174
175 return sprintf(buf, "%s\n",
176 cable->edev->supported_cable[cable->cable_index]);
177}
178
179static ssize_t cable_state_show(struct device *dev,
180 struct device_attribute *attr, char *buf)
181{
182 struct extcon_cable *cable = container_of(attr, struct extcon_cable,
183 attr_state);
184
185 return sprintf(buf, "%d\n",
186 extcon_get_cable_state_(cable->edev,
187 cable->cable_index));
188}
189
190/**
191 * extcon_update_state() - Update the cable attach states of the extcon device
192 * only for the masked bits.
193 * @edev: the extcon device
194 * @mask: the bit mask to designate updated bits.
195 * @state: new cable attach status for @edev
196 *
197 * Changing the state sends uevent with environment variable containing
198 * the name of extcon device (envp[0]) and the state output (envp[1]).
199 * Tizen uses this format for extcon device to get events from ports.
200 * Android uses this format as well.
201 *
202 * Note that the notifier provides which bits are changed in the state
203 * variable with the val parameter (second) to the callback.
204 */
205int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state)
206{
207 char name_buf[120];
208 char state_buf[120];
209 char *prop_buf;
210 char *envp[3];
211 int env_offset = 0;
212 int length;
213 unsigned long flags;
214
215 spin_lock_irqsave(&edev->lock, flags);
216
217 if (edev->state != ((edev->state & ~mask) | (state & mask))) {
218 u32 old_state = edev->state;
219
220 if (check_mutually_exclusive(edev, (edev->state & ~mask) |
221 (state & mask))) {
222 spin_unlock_irqrestore(&edev->lock, flags);
223 return -EPERM;
224 }
225
226 edev->state &= ~mask;
227 edev->state |= state & mask;
228
229 raw_notifier_call_chain(&edev->nh, old_state, edev);
230 /* This could be in interrupt handler */
231 prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
232 if (prop_buf) {
233 length = name_show(&edev->dev, NULL, prop_buf);
234 if (length > 0) {
235 if (prop_buf[length - 1] == '\n')
236 prop_buf[length - 1] = 0;
237 snprintf(name_buf, sizeof(name_buf),
238 "NAME=%s", prop_buf);
239 envp[env_offset++] = name_buf;
240 }
241 length = state_show(&edev->dev, NULL, prop_buf);
242 if (length > 0) {
243 if (prop_buf[length - 1] == '\n')
244 prop_buf[length - 1] = 0;
245 snprintf(state_buf, sizeof(state_buf),
246 "STATE=%s", prop_buf);
247 envp[env_offset++] = state_buf;
248 }
249 envp[env_offset] = NULL;
250 /* Unlock early before uevent */
251 spin_unlock_irqrestore(&edev->lock, flags);
252
253 kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp);
254 free_page((unsigned long)prop_buf);
255 } else {
256 /* Unlock early before uevent */
257 spin_unlock_irqrestore(&edev->lock, flags);
258
259 dev_err(&edev->dev, "out of memory in extcon_set_state\n");
260 kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE);
261 }
262 } else {
263 /* No changes */
264 spin_unlock_irqrestore(&edev->lock, flags);
265 }
266
267 return 0;
268}
269EXPORT_SYMBOL_GPL(extcon_update_state);
270
271/**
272 * extcon_set_state() - Set the cable attach states of the extcon device.
273 * @edev: the extcon device
274 * @state: new cable attach status for @edev
275 *
276 * Note that notifier provides which bits are changed in the state
277 * variable with the val parameter (second) to the callback.
278 */
279int extcon_set_state(struct extcon_dev *edev, u32 state)
280{
281 return extcon_update_state(edev, 0xffffffff, state);
282}
283EXPORT_SYMBOL_GPL(extcon_set_state);
284
285/**
286 * extcon_find_cable_index() - Get the cable index based on the cable name.
287 * @edev: the extcon device that has the cable.
288 * @cable_name: cable name to be searched.
289 *
290 * Note that accessing a cable state based on cable_index is faster than
291 * cable_name because using cable_name induces a loop with strncmp().
292 * Thus, when get/set_cable_state is repeatedly used, using cable_index
293 * is recommended.
294 */
295int extcon_find_cable_index(struct extcon_dev *edev, const char *cable_name)
296{
297 int i;
298
299 if (edev->supported_cable) {
300 for (i = 0; edev->supported_cable[i]; i++) {
301 if (!strncmp(edev->supported_cable[i],
302 cable_name, CABLE_NAME_MAX))
303 return i;
304 }
305 }
306
307 return -EINVAL;
308}
309EXPORT_SYMBOL_GPL(extcon_find_cable_index);
310
311/**
312 * extcon_get_cable_state_() - Get the status of a specific cable.
313 * @edev: the extcon device that has the cable.
314 * @index: cable index that can be retrieved by extcon_find_cable_index().
315 */
316int extcon_get_cable_state_(struct extcon_dev *edev, int index)
317{
318 if (index < 0 || (edev->max_supported && edev->max_supported <= index))
319 return -EINVAL;
320
321 return !!(edev->state & (1 << index));
322}
323EXPORT_SYMBOL_GPL(extcon_get_cable_state_);
324
325/**
326 * extcon_get_cable_state() - Get the status of a specific cable.
327 * @edev: the extcon device that has the cable.
328 * @cable_name: cable name.
329 *
330 * Note that this is slower than extcon_get_cable_state_.
331 */
332int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name)
333{
334 return extcon_get_cable_state_(edev, extcon_find_cable_index
335 (edev, cable_name));
336}
337EXPORT_SYMBOL_GPL(extcon_get_cable_state);
338
339/**
340 * extcon_set_cable_state_() - Set the status of a specific cable.
341 * @edev: the extcon device that has the cable.
342 * @index: cable index that can be retrieved by
343 * extcon_find_cable_index().
344 * @cable_state: the new cable status. The default semantics is
345 * true: attached / false: detached.
346 */
347int extcon_set_cable_state_(struct extcon_dev *edev,
348 int index, bool cable_state)
349{
350 u32 state;
351
352 if (index < 0 || (edev->max_supported && edev->max_supported <= index))
353 return -EINVAL;
354
355 state = cable_state ? (1 << index) : 0;
356 return extcon_update_state(edev, 1 << index, state);
357}
358EXPORT_SYMBOL_GPL(extcon_set_cable_state_);
359
360/**
361 * extcon_set_cable_state() - Set the status of a specific cable.
362 * @edev: the extcon device that has the cable.
363 * @cable_name: cable name.
364 * @cable_state: the new cable status. The default semantics is
365 * true: attached / false: detached.
366 *
367 * Note that this is slower than extcon_set_cable_state_.
368 */
369int extcon_set_cable_state(struct extcon_dev *edev,
370 const char *cable_name, bool cable_state)
371{
372 return extcon_set_cable_state_(edev, extcon_find_cable_index
373 (edev, cable_name), cable_state);
374}
375EXPORT_SYMBOL_GPL(extcon_set_cable_state);
376
377/**
378 * extcon_get_extcon_dev() - Get the extcon device instance from the name
379 * @extcon_name: The extcon name provided with extcon_dev_register()
380 */
381struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
382{
383 struct extcon_dev *sd;
384
385 mutex_lock(&extcon_dev_list_lock);
386 list_for_each_entry(sd, &extcon_dev_list, entry) {
387 if (!strcmp(sd->name, extcon_name))
388 goto out;
389 }
390 sd = NULL;
391out:
392 mutex_unlock(&extcon_dev_list_lock);
393 return sd;
394}
395EXPORT_SYMBOL_GPL(extcon_get_extcon_dev);
396
397static int _call_per_cable(struct notifier_block *nb, unsigned long val,
398 void *ptr)
399{
400 struct extcon_specific_cable_nb *obj = container_of(nb,
401 struct extcon_specific_cable_nb, internal_nb);
402 struct extcon_dev *edev = ptr;
403
404 if ((val & (1 << obj->cable_index)) !=
405 (edev->state & (1 << obj->cable_index))) {
406 bool cable_state = true;
407
408 obj->previous_value = val;
409
410 if (val & (1 << obj->cable_index))
411 cable_state = false;
412
413 return obj->user_nb->notifier_call(obj->user_nb,
414 cable_state, ptr);
415 }
416
417 return NOTIFY_OK;
418}
419
420/**
421 * extcon_register_interest() - Register a notifier for a state change of a
422 * specific cable, not an entier set of cables of a
423 * extcon device.
424 * @obj: an empty extcon_specific_cable_nb object to be returned.
425 * @extcon_name: the name of extcon device.
426 * if NULL, extcon_register_interest will register
427 * every cable with the target cable_name given.
428 * @cable_name: the target cable name.
429 * @nb: the notifier block to get notified.
430 *
431 * Provide an empty extcon_specific_cable_nb. extcon_register_interest() sets
432 * the struct for you.
433 *
434 * extcon_register_interest is a helper function for those who want to get
435 * notification for a single specific cable's status change. If a user wants
436 * to get notification for any changes of all cables of a extcon device,
437 * he/she should use the general extcon_register_notifier().
438 *
439 * Note that the second parameter given to the callback of nb (val) is
440 * "old_state", not the current state. The current state can be retrieved
441 * by looking at the third pameter (edev pointer)'s state value.
442 */
443int extcon_register_interest(struct extcon_specific_cable_nb *obj,
444 const char *extcon_name, const char *cable_name,
445 struct notifier_block *nb)
446{
447 if (!obj || !cable_name || !nb)
448 return -EINVAL;
449
450 if (extcon_name) {
451 obj->edev = extcon_get_extcon_dev(extcon_name);
452 if (!obj->edev)
453 return -ENODEV;
454
455 obj->cable_index = extcon_find_cable_index(obj->edev,
456 cable_name);
457 if (obj->cable_index < 0)
458 return obj->cable_index;
459
460 obj->user_nb = nb;
461
462 obj->internal_nb.notifier_call = _call_per_cable;
463
464 return raw_notifier_chain_register(&obj->edev->nh,
465 &obj->internal_nb);
466 } else {
467 struct class_dev_iter iter;
468 struct extcon_dev *extd;
469 struct device *dev;
470
471 if (!extcon_class)
472 return -ENODEV;
473 class_dev_iter_init(&iter, extcon_class, NULL, NULL);
474 while ((dev = class_dev_iter_next(&iter))) {
475 extd = dev_get_drvdata(dev);
476
477 if (extcon_find_cable_index(extd, cable_name) < 0)
478 continue;
479
480 class_dev_iter_exit(&iter);
481 return extcon_register_interest(obj, extd->name,
482 cable_name, nb);
483 }
484
485 return -ENODEV;
486 }
487}
488EXPORT_SYMBOL_GPL(extcon_register_interest);
489
490/**
491 * extcon_unregister_interest() - Unregister the notifier registered by
492 * extcon_register_interest().
493 * @obj: the extcon_specific_cable_nb object returned by
494 * extcon_register_interest().
495 */
496int extcon_unregister_interest(struct extcon_specific_cable_nb *obj)
497{
498 if (!obj)
499 return -EINVAL;
500
501 return raw_notifier_chain_unregister(&obj->edev->nh, &obj->internal_nb);
502}
503EXPORT_SYMBOL_GPL(extcon_unregister_interest);
504
505/**
506 * extcon_register_notifier() - Register a notifiee to get notified by
507 * any attach status changes from the extcon.
508 * @edev: the extcon device.
509 * @nb: a notifier block to be registered.
510 *
511 * Note that the second parameter given to the callback of nb (val) is
512 * "old_state", not the current state. The current state can be retrieved
513 * by looking at the third pameter (edev pointer)'s state value.
514 */
515int extcon_register_notifier(struct extcon_dev *edev,
516 struct notifier_block *nb)
517{
518 return raw_notifier_chain_register(&edev->nh, nb);
519}
520EXPORT_SYMBOL_GPL(extcon_register_notifier);
521
522/**
523 * extcon_unregister_notifier() - Unregister a notifiee from the extcon device.
524 * @edev: the extcon device.
525 * @nb: a registered notifier block to be unregistered.
526 */
527int extcon_unregister_notifier(struct extcon_dev *edev,
528 struct notifier_block *nb)
529{
530 return raw_notifier_chain_unregister(&edev->nh, nb);
531}
532EXPORT_SYMBOL_GPL(extcon_unregister_notifier);
533
534static struct attribute *extcon_attrs[] = {
535 &dev_attr_state.attr,
536 &dev_attr_name.attr,
537 NULL,
538};
539ATTRIBUTE_GROUPS(extcon);
540
541static int create_extcon_class(void)
542{
543 if (!extcon_class) {
544 extcon_class = class_create(THIS_MODULE, "extcon");
545 if (IS_ERR(extcon_class))
546 return PTR_ERR(extcon_class);
547 extcon_class->dev_groups = extcon_groups;
548
549#if defined(CONFIG_ANDROID)
550 switch_class = class_compat_register("switch");
551 if (WARN(!switch_class, "cannot allocate"))
552 return -ENOMEM;
553#endif /* CONFIG_ANDROID */
554 }
555
556 return 0;
557}
558
559static void extcon_dev_release(struct device *dev)
560{
561}
562
563static const char *muex_name = "mutually_exclusive";
564static void dummy_sysfs_dev_release(struct device *dev)
565{
566}
567
568/*
569 * extcon_dev_allocate() - Allocate the memory of extcon device.
570 * @supported_cable: Array of supported cable names ending with NULL.
571 * If supported_cable is NULL, cable name related APIs
572 * are disabled.
573 *
574 * This function allocates the memory for extcon device without allocating
575 * memory in each extcon provider driver and initialize default setting for
576 * extcon device.
577 *
578 * Return the pointer of extcon device if success or ERR_PTR(err) if fail
579 */
580struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
581{
582 struct extcon_dev *edev;
583
584 edev = kzalloc(sizeof(*edev), GFP_KERNEL);
585 if (!edev)
586 return ERR_PTR(-ENOMEM);
587
588 edev->max_supported = 0;
589 edev->supported_cable = supported_cable;
590
591 return edev;
592}
593
594/*
595 * extcon_dev_free() - Free the memory of extcon device.
596 * @edev: the extcon device to free
597 */
598void extcon_dev_free(struct extcon_dev *edev)
599{
600 kfree(edev);
601}
602EXPORT_SYMBOL_GPL(extcon_dev_free);
603
604static int devm_extcon_dev_match(struct device *dev, void *res, void *data)
605{
606 struct extcon_dev **r = res;
607
608 if (WARN_ON(!r || !*r))
609 return 0;
610
611 return *r == data;
612}
613
614static void devm_extcon_dev_release(struct device *dev, void *res)
615{
616 extcon_dev_free(*(struct extcon_dev **)res);
617}
618
619/**
620 * devm_extcon_dev_allocate - Allocate managed extcon device
621 * @dev: device owning the extcon device being created
622 * @supported_cable: Array of supported cable names ending with NULL.
623 * If supported_cable is NULL, cable name related APIs
624 * are disabled.
625 *
626 * This function manages automatically the memory of extcon device using device
627 * resource management and simplify the control of freeing the memory of extcon
628 * device.
629 *
630 * Returns the pointer memory of allocated extcon_dev if success
631 * or ERR_PTR(err) if fail
632 */
633struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
634 const char **supported_cable)
635{
636 struct extcon_dev **ptr, *edev;
637
638 ptr = devres_alloc(devm_extcon_dev_release, sizeof(*ptr), GFP_KERNEL);
639 if (!ptr)
640 return ERR_PTR(-ENOMEM);
641
642 edev = extcon_dev_allocate(supported_cable);
643 if (IS_ERR(edev)) {
644 devres_free(ptr);
645 return edev;
646 }
647
648 edev->dev.parent = dev;
649
650 *ptr = edev;
651 devres_add(dev, ptr);
652
653 return edev;
654}
655EXPORT_SYMBOL_GPL(devm_extcon_dev_allocate);
656
657void devm_extcon_dev_free(struct device *dev, struct extcon_dev *edev)
658{
659 WARN_ON(devres_release(dev, devm_extcon_dev_release,
660 devm_extcon_dev_match, edev));
661}
662EXPORT_SYMBOL_GPL(devm_extcon_dev_free);
663
664/**
665 * extcon_dev_register() - Register a new extcon device
666 * @edev : the new extcon device (should be allocated before calling)
667 *
668 * Among the members of edev struct, please set the "user initializing data"
669 * in any case and set the "optional callbacks" if required. However, please
670 * do not set the values of "internal data", which are initialized by
671 * this function.
672 */
673int extcon_dev_register(struct extcon_dev *edev)
674{
675 int ret, index = 0;
676
677 if (!extcon_class) {
678 ret = create_extcon_class();
679 if (ret < 0)
680 return ret;
681 }
682
683 if (edev->supported_cable) {
684 /* Get size of array */
685 for (index = 0; edev->supported_cable[index]; index++)
686 ;
687 edev->max_supported = index;
688 } else {
689 edev->max_supported = 0;
690 }
691
692 if (index > SUPPORTED_CABLE_MAX) {
693 dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
694 return -EINVAL;
695 }
696
697 edev->dev.class = extcon_class;
698 edev->dev.release = extcon_dev_release;
699
700 edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
701 if (IS_ERR_OR_NULL(edev->name)) {
702 dev_err(&edev->dev,
703 "extcon device name is null\n");
704 return -EINVAL;
705 }
706 dev_set_name(&edev->dev, "%s", edev->name);
707
708 if (edev->max_supported) {
709 char buf[10];
710 char *str;
711 struct extcon_cable *cable;
712
713 edev->cables = kzalloc(sizeof(struct extcon_cable) *
714 edev->max_supported, GFP_KERNEL);
715 if (!edev->cables) {
716 ret = -ENOMEM;
717 goto err_sysfs_alloc;
718 }
719 for (index = 0; index < edev->max_supported; index++) {
720 cable = &edev->cables[index];
721
722 snprintf(buf, 10, "cable.%d", index);
723 str = kzalloc(sizeof(char) * (strlen(buf) + 1),
724 GFP_KERNEL);
725 if (!str) {
726 for (index--; index >= 0; index--) {
727 cable = &edev->cables[index];
728 kfree(cable->attr_g.name);
729 }
730 ret = -ENOMEM;
731
732 goto err_alloc_cables;
733 }
734 strcpy(str, buf);
735
736 cable->edev = edev;
737 cable->cable_index = index;
738 cable->attrs[0] = &cable->attr_name.attr;
739 cable->attrs[1] = &cable->attr_state.attr;
740 cable->attrs[2] = NULL;
741 cable->attr_g.name = str;
742 cable->attr_g.attrs = cable->attrs;
743
744 sysfs_attr_init(&cable->attr_name.attr);
745 cable->attr_name.attr.name = "name";
746 cable->attr_name.attr.mode = 0444;
747 cable->attr_name.show = cable_name_show;
748
749 sysfs_attr_init(&cable->attr_state.attr);
750 cable->attr_state.attr.name = "state";
751 cable->attr_state.attr.mode = 0444;
752 cable->attr_state.show = cable_state_show;
753 }
754 }
755
756 if (edev->max_supported && edev->mutually_exclusive) {
757 char buf[80];
758 char *name;
759
760 /* Count the size of mutually_exclusive array */
761 for (index = 0; edev->mutually_exclusive[index]; index++)
762 ;
763
764 edev->attrs_muex = kzalloc(sizeof(struct attribute *) *
765 (index + 1), GFP_KERNEL);
766 if (!edev->attrs_muex) {
767 ret = -ENOMEM;
768 goto err_muex;
769 }
770
771 edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) *
772 index, GFP_KERNEL);
773 if (!edev->d_attrs_muex) {
774 ret = -ENOMEM;
775 kfree(edev->attrs_muex);
776 goto err_muex;
777 }
778
779 for (index = 0; edev->mutually_exclusive[index]; index++) {
780 sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
781 name = kzalloc(sizeof(char) * (strlen(buf) + 1),
782 GFP_KERNEL);
783 if (!name) {
784 for (index--; index >= 0; index--) {
785 kfree(edev->d_attrs_muex[index].attr.
786 name);
787 }
788 kfree(edev->d_attrs_muex);
789 kfree(edev->attrs_muex);
790 ret = -ENOMEM;
791 goto err_muex;
792 }
793 strcpy(name, buf);
794 sysfs_attr_init(&edev->d_attrs_muex[index].attr);
795 edev->d_attrs_muex[index].attr.name = name;
796 edev->d_attrs_muex[index].attr.mode = 0000;
797 edev->attrs_muex[index] = &edev->d_attrs_muex[index]
798 .attr;
799 }
800 edev->attr_g_muex.name = muex_name;
801 edev->attr_g_muex.attrs = edev->attrs_muex;
802
803 }
804
805 if (edev->max_supported) {
806 edev->extcon_dev_type.groups =
807 kzalloc(sizeof(struct attribute_group *) *
808 (edev->max_supported + 2), GFP_KERNEL);
809 if (!edev->extcon_dev_type.groups) {
810 ret = -ENOMEM;
811 goto err_alloc_groups;
812 }
813
814 edev->extcon_dev_type.name = dev_name(&edev->dev);
815 edev->extcon_dev_type.release = dummy_sysfs_dev_release;
816
817 for (index = 0; index < edev->max_supported; index++)
818 edev->extcon_dev_type.groups[index] =
819 &edev->cables[index].attr_g;
820 if (edev->mutually_exclusive)
821 edev->extcon_dev_type.groups[index] =
822 &edev->attr_g_muex;
823
824 edev->dev.type = &edev->extcon_dev_type;
825 }
826
827 ret = device_register(&edev->dev);
828 if (ret) {
829 put_device(&edev->dev);
830 goto err_dev;
831 }
832#if defined(CONFIG_ANDROID)
833 if (switch_class)
834 ret = class_compat_create_link(switch_class, &edev->dev, NULL);
835#endif /* CONFIG_ANDROID */
836
837 spin_lock_init(&edev->lock);
838
839 RAW_INIT_NOTIFIER_HEAD(&edev->nh);
840
841 dev_set_drvdata(&edev->dev, edev);
842 edev->state = 0;
843
844 mutex_lock(&extcon_dev_list_lock);
845 list_add(&edev->entry, &extcon_dev_list);
846 mutex_unlock(&extcon_dev_list_lock);
847
848 return 0;
849
850err_dev:
851 if (edev->max_supported)
852 kfree(edev->extcon_dev_type.groups);
853err_alloc_groups:
854 if (edev->max_supported && edev->mutually_exclusive) {
855 for (index = 0; edev->mutually_exclusive[index]; index++)
856 kfree(edev->d_attrs_muex[index].attr.name);
857 kfree(edev->d_attrs_muex);
858 kfree(edev->attrs_muex);
859 }
860err_muex:
861 for (index = 0; index < edev->max_supported; index++)
862 kfree(edev->cables[index].attr_g.name);
863err_alloc_cables:
864 if (edev->max_supported)
865 kfree(edev->cables);
866err_sysfs_alloc:
867 return ret;
868}
869EXPORT_SYMBOL_GPL(extcon_dev_register);
870
871/**
872 * extcon_dev_unregister() - Unregister the extcon device.
873 * @edev: the extcon device instance to be unregistered.
874 *
875 * Note that this does not call kfree(edev) because edev was not allocated
876 * by this class.
877 */
878void extcon_dev_unregister(struct extcon_dev *edev)
879{
880 int index;
881
882 mutex_lock(&extcon_dev_list_lock);
883 list_del(&edev->entry);
884 mutex_unlock(&extcon_dev_list_lock);
885
886 if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
887 dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
888 dev_name(&edev->dev));
889 return;
890 }
891
892 device_unregister(&edev->dev);
893
894 if (edev->mutually_exclusive && edev->max_supported) {
895 for (index = 0; edev->mutually_exclusive[index];
896 index++)
897 kfree(edev->d_attrs_muex[index].attr.name);
898 kfree(edev->d_attrs_muex);
899 kfree(edev->attrs_muex);
900 }
901
902 for (index = 0; index < edev->max_supported; index++)
903 kfree(edev->cables[index].attr_g.name);
904
905 if (edev->max_supported) {
906 kfree(edev->extcon_dev_type.groups);
907 kfree(edev->cables);
908 }
909
910#if defined(CONFIG_ANDROID)
911 if (switch_class)
912 class_compat_remove_link(switch_class, &edev->dev, NULL);
913#endif
914 put_device(&edev->dev);
915}
916EXPORT_SYMBOL_GPL(extcon_dev_unregister);
917
918static void devm_extcon_dev_unreg(struct device *dev, void *res)
919{
920 extcon_dev_unregister(*(struct extcon_dev **)res);
921}
922
923/**
924 * devm_extcon_dev_register() - Resource-managed extcon_dev_register()
925 * @dev: device to allocate extcon device
926 * @edev: the new extcon device to register
927 *
928 * Managed extcon_dev_register() function. If extcon device is attached with
929 * this function, that extcon device is automatically unregistered on driver
930 * detach. Internally this function calls extcon_dev_register() function.
931 * To get more information, refer that function.
932 *
933 * If extcon device is registered with this function and the device needs to be
934 * unregistered separately, devm_extcon_dev_unregister() should be used.
935 *
936 * Returns 0 if success or negaive error number if failure.
937 */
938int devm_extcon_dev_register(struct device *dev, struct extcon_dev *edev)
939{
940 struct extcon_dev **ptr;
941 int ret;
942
943 ptr = devres_alloc(devm_extcon_dev_unreg, sizeof(*ptr), GFP_KERNEL);
944 if (!ptr)
945 return -ENOMEM;
946
947 ret = extcon_dev_register(edev);
948 if (ret) {
949 devres_free(ptr);
950 return ret;
951 }
952
953 *ptr = edev;
954 devres_add(dev, ptr);
955
956 return 0;
957}
958EXPORT_SYMBOL_GPL(devm_extcon_dev_register);
959
960/**
961 * devm_extcon_dev_unregister() - Resource-managed extcon_dev_unregister()
962 * @dev: device the extcon belongs to
963 * @edev: the extcon device to unregister
964 *
965 * Unregister extcon device that is registered with devm_extcon_dev_register()
966 * function.
967 */
968void devm_extcon_dev_unregister(struct device *dev, struct extcon_dev *edev)
969{
970 WARN_ON(devres_release(dev, devm_extcon_dev_unreg,
971 devm_extcon_dev_match, edev));
972}
973EXPORT_SYMBOL_GPL(devm_extcon_dev_unregister);
974
975#ifdef CONFIG_OF
976/*
977 * extcon_get_edev_by_phandle - Get the extcon device from devicetree
978 * @dev - instance to the given device
979 * @index - index into list of extcon_dev
980 *
981 * return the instance of extcon device
982 */
983struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
984{
985 struct device_node *node;
986 struct extcon_dev *edev;
987
988 if (!dev->of_node) {
989 dev_err(dev, "device does not have a device node entry\n");
990 return ERR_PTR(-EINVAL);
991 }
992
993 node = of_parse_phandle(dev->of_node, "extcon", index);
994 if (!node) {
995 dev_err(dev, "failed to get phandle in %s node\n",
996 dev->of_node->full_name);
997 return ERR_PTR(-ENODEV);
998 }
999
1000 mutex_lock(&extcon_dev_list_lock);
1001 list_for_each_entry(edev, &extcon_dev_list, entry) {
1002 if (edev->dev.parent && edev->dev.parent->of_node == node) {
1003 mutex_unlock(&extcon_dev_list_lock);
1004 return edev;
1005 }
1006 }
1007 mutex_unlock(&extcon_dev_list_lock);
1008
1009 return ERR_PTR(-EPROBE_DEFER);
1010}
1011#else
1012struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
1013{
1014 return ERR_PTR(-ENOSYS);
1015}
1016#endif /* CONFIG_OF */
1017EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
1018
1019static int __init extcon_class_init(void)
1020{
1021 return create_extcon_class();
1022}
1023module_init(extcon_class_init);
1024
1025static void __exit extcon_class_exit(void)
1026{
1027#if defined(CONFIG_ANDROID)
1028 class_compat_unregister(switch_class);
1029#endif
1030 class_destroy(extcon_class);
1031}
1032module_exit(extcon_class_exit);
1033
1034MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
1035MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
1036MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
1037MODULE_DESCRIPTION("External connector (extcon) class driver");
1038MODULE_LICENSE("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2025-06-01 16:35:28 -0400