xref: /linux/drivers/usb/gadget/configfs.c (revision 45d8b572fac3aa8b49d53c946b3685eaf78a2824)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/configfs.h>
3 #include <linux/module.h>
4 #include <linux/slab.h>
5 #include <linux/device.h>
6 #include <linux/kstrtox.h>
7 #include <linux/nls.h>
8 #include <linux/usb/composite.h>
9 #include <linux/usb/gadget_configfs.h>
10 #include <linux/usb/webusb.h>
11 #include "configfs.h"
12 #include "u_f.h"
13 #include "u_os_desc.h"
14 
15 int check_user_usb_string(const char *name,
16 		struct usb_gadget_strings *stringtab_dev)
17 {
18 	u16 num;
19 	int ret;
20 
21 	ret = kstrtou16(name, 0, &num);
22 	if (ret)
23 		return ret;
24 
25 	if (!usb_validate_langid(num))
26 		return -EINVAL;
27 
28 	stringtab_dev->language = num;
29 	return 0;
30 }
31 
32 #define MAX_NAME_LEN	40
33 #define MAX_USB_STRING_LANGS 2
34 
35 static const struct usb_descriptor_header *otg_desc[2];
36 
37 struct gadget_info {
38 	struct config_group group;
39 	struct config_group functions_group;
40 	struct config_group configs_group;
41 	struct config_group strings_group;
42 	struct config_group os_desc_group;
43 	struct config_group webusb_group;
44 
45 	struct mutex lock;
46 	struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
47 	struct list_head string_list;
48 	struct list_head available_func;
49 
50 	struct usb_composite_driver composite;
51 	struct usb_composite_dev cdev;
52 	bool use_os_desc;
53 	char b_vendor_code;
54 	char qw_sign[OS_STRING_QW_SIGN_LEN];
55 	bool use_webusb;
56 	u16 bcd_webusb_version;
57 	u8 b_webusb_vendor_code;
58 	char landing_page[WEBUSB_URL_RAW_MAX_LENGTH];
59 
60 	spinlock_t spinlock;
61 	bool unbind;
62 };
63 
64 static inline struct gadget_info *to_gadget_info(struct config_item *item)
65 {
66 	return container_of(to_config_group(item), struct gadget_info, group);
67 }
68 
69 struct config_usb_cfg {
70 	struct config_group group;
71 	struct config_group strings_group;
72 	struct list_head string_list;
73 	struct usb_configuration c;
74 	struct list_head func_list;
75 	struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
76 };
77 
78 static inline struct config_usb_cfg *to_config_usb_cfg(struct config_item *item)
79 {
80 	return container_of(to_config_group(item), struct config_usb_cfg,
81 			group);
82 }
83 
84 static inline struct gadget_info *cfg_to_gadget_info(struct config_usb_cfg *cfg)
85 {
86 	return container_of(cfg->c.cdev, struct gadget_info, cdev);
87 }
88 
89 struct gadget_language {
90 	struct usb_gadget_strings stringtab_dev;
91 	struct usb_string strings[USB_GADGET_FIRST_AVAIL_IDX];
92 	char *manufacturer;
93 	char *product;
94 	char *serialnumber;
95 
96 	struct config_group group;
97 	struct list_head list;
98 	struct list_head gadget_strings;
99 	unsigned int nstrings;
100 };
101 
102 struct gadget_config_name {
103 	struct usb_gadget_strings stringtab_dev;
104 	struct usb_string strings;
105 	char *configuration;
106 
107 	struct config_group group;
108 	struct list_head list;
109 };
110 
111 #define USB_MAX_STRING_WITH_NULL_LEN	(USB_MAX_STRING_LEN+1)
112 
113 static int usb_string_copy(const char *s, char **s_copy)
114 {
115 	int ret;
116 	char *str;
117 	char *copy = *s_copy;
118 	ret = strlen(s);
119 	if (ret > USB_MAX_STRING_LEN)
120 		return -EOVERFLOW;
121 
122 	if (copy) {
123 		str = copy;
124 	} else {
125 		str = kmalloc(USB_MAX_STRING_WITH_NULL_LEN, GFP_KERNEL);
126 		if (!str)
127 			return -ENOMEM;
128 	}
129 	strcpy(str, s);
130 	if (str[ret - 1] == '\n')
131 		str[ret - 1] = '\0';
132 	*s_copy = str;
133 	return 0;
134 }
135 
136 #define GI_DEVICE_DESC_SIMPLE_R_u8(__name)	\
137 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
138 			char *page)	\
139 {	\
140 	return sprintf(page, "0x%02x\n", \
141 		to_gadget_info(item)->cdev.desc.__name); \
142 }
143 
144 #define GI_DEVICE_DESC_SIMPLE_R_u16(__name)	\
145 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
146 			char *page)	\
147 {	\
148 	return sprintf(page, "0x%04x\n", \
149 		le16_to_cpup(&to_gadget_info(item)->cdev.desc.__name)); \
150 }
151 
152 
153 #define GI_DEVICE_DESC_SIMPLE_W_u8(_name)		\
154 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
155 		const char *page, size_t len)		\
156 {							\
157 	u8 val;						\
158 	int ret;					\
159 	ret = kstrtou8(page, 0, &val);			\
160 	if (ret)					\
161 		return ret;				\
162 	to_gadget_info(item)->cdev.desc._name = val;	\
163 	return len;					\
164 }
165 
166 #define GI_DEVICE_DESC_SIMPLE_W_u16(_name)	\
167 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
168 		const char *page, size_t len)		\
169 {							\
170 	u16 val;					\
171 	int ret;					\
172 	ret = kstrtou16(page, 0, &val);			\
173 	if (ret)					\
174 		return ret;				\
175 	to_gadget_info(item)->cdev.desc._name = cpu_to_le16p(&val);	\
176 	return len;					\
177 }
178 
179 #define GI_DEVICE_DESC_SIMPLE_RW(_name, _type)	\
180 	GI_DEVICE_DESC_SIMPLE_R_##_type(_name)	\
181 	GI_DEVICE_DESC_SIMPLE_W_##_type(_name)
182 
183 GI_DEVICE_DESC_SIMPLE_R_u16(bcdUSB);
184 GI_DEVICE_DESC_SIMPLE_RW(bDeviceClass, u8);
185 GI_DEVICE_DESC_SIMPLE_RW(bDeviceSubClass, u8);
186 GI_DEVICE_DESC_SIMPLE_RW(bDeviceProtocol, u8);
187 GI_DEVICE_DESC_SIMPLE_RW(bMaxPacketSize0, u8);
188 GI_DEVICE_DESC_SIMPLE_RW(idVendor, u16);
189 GI_DEVICE_DESC_SIMPLE_RW(idProduct, u16);
190 GI_DEVICE_DESC_SIMPLE_R_u16(bcdDevice);
191 
192 static ssize_t is_valid_bcd(u16 bcd_val)
193 {
194 	if ((bcd_val & 0xf) > 9)
195 		return -EINVAL;
196 	if (((bcd_val >> 4) & 0xf) > 9)
197 		return -EINVAL;
198 	if (((bcd_val >> 8) & 0xf) > 9)
199 		return -EINVAL;
200 	if (((bcd_val >> 12) & 0xf) > 9)
201 		return -EINVAL;
202 	return 0;
203 }
204 
205 static ssize_t gadget_dev_desc_bcdDevice_store(struct config_item *item,
206 		const char *page, size_t len)
207 {
208 	u16 bcdDevice;
209 	int ret;
210 
211 	ret = kstrtou16(page, 0, &bcdDevice);
212 	if (ret)
213 		return ret;
214 	ret = is_valid_bcd(bcdDevice);
215 	if (ret)
216 		return ret;
217 
218 	to_gadget_info(item)->cdev.desc.bcdDevice = cpu_to_le16(bcdDevice);
219 	return len;
220 }
221 
222 static ssize_t gadget_dev_desc_bcdUSB_store(struct config_item *item,
223 		const char *page, size_t len)
224 {
225 	u16 bcdUSB;
226 	int ret;
227 
228 	ret = kstrtou16(page, 0, &bcdUSB);
229 	if (ret)
230 		return ret;
231 	ret = is_valid_bcd(bcdUSB);
232 	if (ret)
233 		return ret;
234 
235 	to_gadget_info(item)->cdev.desc.bcdUSB = cpu_to_le16(bcdUSB);
236 	return len;
237 }
238 
239 static ssize_t gadget_dev_desc_UDC_show(struct config_item *item, char *page)
240 {
241 	struct gadget_info *gi = to_gadget_info(item);
242 	char *udc_name;
243 	int ret;
244 
245 	mutex_lock(&gi->lock);
246 	udc_name = gi->composite.gadget_driver.udc_name;
247 	ret = sprintf(page, "%s\n", udc_name ?: "");
248 	mutex_unlock(&gi->lock);
249 
250 	return ret;
251 }
252 
253 static int unregister_gadget(struct gadget_info *gi)
254 {
255 	int ret;
256 
257 	if (!gi->composite.gadget_driver.udc_name)
258 		return -ENODEV;
259 
260 	ret = usb_gadget_unregister_driver(&gi->composite.gadget_driver);
261 	if (ret)
262 		return ret;
263 	kfree(gi->composite.gadget_driver.udc_name);
264 	gi->composite.gadget_driver.udc_name = NULL;
265 	return 0;
266 }
267 
268 static ssize_t gadget_dev_desc_UDC_store(struct config_item *item,
269 		const char *page, size_t len)
270 {
271 	struct gadget_info *gi = to_gadget_info(item);
272 	char *name;
273 	int ret;
274 
275 	if (strlen(page) < len)
276 		return -EOVERFLOW;
277 
278 	name = kstrdup(page, GFP_KERNEL);
279 	if (!name)
280 		return -ENOMEM;
281 	if (name[len - 1] == '\n')
282 		name[len - 1] = '\0';
283 
284 	mutex_lock(&gi->lock);
285 
286 	if (!strlen(name)) {
287 		ret = unregister_gadget(gi);
288 		if (ret)
289 			goto err;
290 		kfree(name);
291 	} else {
292 		if (gi->composite.gadget_driver.udc_name) {
293 			ret = -EBUSY;
294 			goto err;
295 		}
296 		gi->composite.gadget_driver.udc_name = name;
297 		ret = usb_gadget_register_driver(&gi->composite.gadget_driver);
298 		if (ret) {
299 			gi->composite.gadget_driver.udc_name = NULL;
300 			goto err;
301 		}
302 	}
303 	mutex_unlock(&gi->lock);
304 	return len;
305 err:
306 	kfree(name);
307 	mutex_unlock(&gi->lock);
308 	return ret;
309 }
310 
311 static ssize_t gadget_dev_desc_max_speed_show(struct config_item *item,
312 					      char *page)
313 {
314 	enum usb_device_speed speed = to_gadget_info(item)->composite.max_speed;
315 
316 	return sprintf(page, "%s\n", usb_speed_string(speed));
317 }
318 
319 static ssize_t gadget_dev_desc_max_speed_store(struct config_item *item,
320 					       const char *page, size_t len)
321 {
322 	struct gadget_info *gi = to_gadget_info(item);
323 
324 	mutex_lock(&gi->lock);
325 
326 	/* Prevent changing of max_speed after the driver is binded */
327 	if (gi->composite.gadget_driver.udc_name)
328 		goto err;
329 
330 	if (strncmp(page, "super-speed-plus", 16) == 0)
331 		gi->composite.max_speed = USB_SPEED_SUPER_PLUS;
332 	else if (strncmp(page, "super-speed", 11) == 0)
333 		gi->composite.max_speed = USB_SPEED_SUPER;
334 	else if (strncmp(page, "high-speed", 10) == 0)
335 		gi->composite.max_speed = USB_SPEED_HIGH;
336 	else if (strncmp(page, "full-speed", 10) == 0)
337 		gi->composite.max_speed = USB_SPEED_FULL;
338 	else if (strncmp(page, "low-speed", 9) == 0)
339 		gi->composite.max_speed = USB_SPEED_LOW;
340 	else
341 		goto err;
342 
343 	gi->composite.gadget_driver.max_speed = gi->composite.max_speed;
344 
345 	mutex_unlock(&gi->lock);
346 	return len;
347 err:
348 	mutex_unlock(&gi->lock);
349 	return -EINVAL;
350 }
351 
352 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceClass);
353 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceSubClass);
354 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceProtocol);
355 CONFIGFS_ATTR(gadget_dev_desc_, bMaxPacketSize0);
356 CONFIGFS_ATTR(gadget_dev_desc_, idVendor);
357 CONFIGFS_ATTR(gadget_dev_desc_, idProduct);
358 CONFIGFS_ATTR(gadget_dev_desc_, bcdDevice);
359 CONFIGFS_ATTR(gadget_dev_desc_, bcdUSB);
360 CONFIGFS_ATTR(gadget_dev_desc_, UDC);
361 CONFIGFS_ATTR(gadget_dev_desc_, max_speed);
362 
363 static struct configfs_attribute *gadget_root_attrs[] = {
364 	&gadget_dev_desc_attr_bDeviceClass,
365 	&gadget_dev_desc_attr_bDeviceSubClass,
366 	&gadget_dev_desc_attr_bDeviceProtocol,
367 	&gadget_dev_desc_attr_bMaxPacketSize0,
368 	&gadget_dev_desc_attr_idVendor,
369 	&gadget_dev_desc_attr_idProduct,
370 	&gadget_dev_desc_attr_bcdDevice,
371 	&gadget_dev_desc_attr_bcdUSB,
372 	&gadget_dev_desc_attr_UDC,
373 	&gadget_dev_desc_attr_max_speed,
374 	NULL,
375 };
376 
377 static inline struct gadget_language *to_gadget_language(struct config_item *item)
378 {
379 	return container_of(to_config_group(item), struct gadget_language,
380 			 group);
381 }
382 
383 static inline struct gadget_config_name *to_gadget_config_name(
384 		struct config_item *item)
385 {
386 	return container_of(to_config_group(item), struct gadget_config_name,
387 			 group);
388 }
389 
390 static inline struct usb_function_instance *to_usb_function_instance(
391 		struct config_item *item)
392 {
393 	return container_of(to_config_group(item),
394 			 struct usb_function_instance, group);
395 }
396 
397 static void gadget_info_attr_release(struct config_item *item)
398 {
399 	struct gadget_info *gi = to_gadget_info(item);
400 
401 	WARN_ON(!list_empty(&gi->cdev.configs));
402 	WARN_ON(!list_empty(&gi->string_list));
403 	WARN_ON(!list_empty(&gi->available_func));
404 	kfree(gi->composite.gadget_driver.function);
405 	kfree(gi->composite.gadget_driver.driver.name);
406 	kfree(gi);
407 }
408 
409 static struct configfs_item_operations gadget_root_item_ops = {
410 	.release                = gadget_info_attr_release,
411 };
412 
413 static void gadget_config_attr_release(struct config_item *item)
414 {
415 	struct config_usb_cfg *cfg = to_config_usb_cfg(item);
416 
417 	WARN_ON(!list_empty(&cfg->c.functions));
418 	list_del(&cfg->c.list);
419 	kfree(cfg->c.label);
420 	kfree(cfg);
421 }
422 
423 static int config_usb_cfg_link(
424 	struct config_item *usb_cfg_ci,
425 	struct config_item *usb_func_ci)
426 {
427 	struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
428 	struct gadget_info *gi = cfg_to_gadget_info(cfg);
429 
430 	struct usb_function_instance *fi =
431 			to_usb_function_instance(usb_func_ci);
432 	struct usb_function_instance *a_fi = NULL, *iter;
433 	struct usb_function *f;
434 	int ret;
435 
436 	mutex_lock(&gi->lock);
437 	/*
438 	 * Make sure this function is from within our _this_ gadget and not
439 	 * from another gadget or a random directory.
440 	 * Also a function instance can only be linked once.
441 	 */
442 
443 	if (gi->composite.gadget_driver.udc_name) {
444 		ret = -EINVAL;
445 		goto out;
446 	}
447 
448 	list_for_each_entry(iter, &gi->available_func, cfs_list) {
449 		if (iter != fi)
450 			continue;
451 		a_fi = iter;
452 		break;
453 	}
454 	if (!a_fi) {
455 		ret = -EINVAL;
456 		goto out;
457 	}
458 
459 	list_for_each_entry(f, &cfg->func_list, list) {
460 		if (f->fi == fi) {
461 			ret = -EEXIST;
462 			goto out;
463 		}
464 	}
465 
466 	f = usb_get_function(fi);
467 	if (IS_ERR(f)) {
468 		ret = PTR_ERR(f);
469 		goto out;
470 	}
471 
472 	/* stash the function until we bind it to the gadget */
473 	list_add_tail(&f->list, &cfg->func_list);
474 	ret = 0;
475 out:
476 	mutex_unlock(&gi->lock);
477 	return ret;
478 }
479 
480 static void config_usb_cfg_unlink(
481 	struct config_item *usb_cfg_ci,
482 	struct config_item *usb_func_ci)
483 {
484 	struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
485 	struct gadget_info *gi = cfg_to_gadget_info(cfg);
486 
487 	struct usb_function_instance *fi =
488 			to_usb_function_instance(usb_func_ci);
489 	struct usb_function *f;
490 
491 	/*
492 	 * ideally I would like to forbid to unlink functions while a gadget is
493 	 * bound to an UDC. Since this isn't possible at the moment, we simply
494 	 * force an unbind, the function is available here and then we can
495 	 * remove the function.
496 	 */
497 	mutex_lock(&gi->lock);
498 	if (gi->composite.gadget_driver.udc_name)
499 		unregister_gadget(gi);
500 	WARN_ON(gi->composite.gadget_driver.udc_name);
501 
502 	list_for_each_entry(f, &cfg->func_list, list) {
503 		if (f->fi == fi) {
504 			list_del(&f->list);
505 			usb_put_function(f);
506 			mutex_unlock(&gi->lock);
507 			return;
508 		}
509 	}
510 	mutex_unlock(&gi->lock);
511 	WARN(1, "Unable to locate function to unbind\n");
512 }
513 
514 static struct configfs_item_operations gadget_config_item_ops = {
515 	.release                = gadget_config_attr_release,
516 	.allow_link             = config_usb_cfg_link,
517 	.drop_link              = config_usb_cfg_unlink,
518 };
519 
520 
521 static ssize_t gadget_config_desc_MaxPower_show(struct config_item *item,
522 		char *page)
523 {
524 	struct config_usb_cfg *cfg = to_config_usb_cfg(item);
525 
526 	return sprintf(page, "%u\n", cfg->c.MaxPower);
527 }
528 
529 static ssize_t gadget_config_desc_MaxPower_store(struct config_item *item,
530 		const char *page, size_t len)
531 {
532 	struct config_usb_cfg *cfg = to_config_usb_cfg(item);
533 	u16 val;
534 	int ret;
535 	ret = kstrtou16(page, 0, &val);
536 	if (ret)
537 		return ret;
538 	if (DIV_ROUND_UP(val, 8) > 0xff)
539 		return -ERANGE;
540 	cfg->c.MaxPower = val;
541 	return len;
542 }
543 
544 static ssize_t gadget_config_desc_bmAttributes_show(struct config_item *item,
545 		char *page)
546 {
547 	struct config_usb_cfg *cfg = to_config_usb_cfg(item);
548 
549 	return sprintf(page, "0x%02x\n", cfg->c.bmAttributes);
550 }
551 
552 static ssize_t gadget_config_desc_bmAttributes_store(struct config_item *item,
553 		const char *page, size_t len)
554 {
555 	struct config_usb_cfg *cfg = to_config_usb_cfg(item);
556 	u8 val;
557 	int ret;
558 	ret = kstrtou8(page, 0, &val);
559 	if (ret)
560 		return ret;
561 	if (!(val & USB_CONFIG_ATT_ONE))
562 		return -EINVAL;
563 	if (val & ~(USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER |
564 				USB_CONFIG_ATT_WAKEUP))
565 		return -EINVAL;
566 	cfg->c.bmAttributes = val;
567 	return len;
568 }
569 
570 CONFIGFS_ATTR(gadget_config_desc_, MaxPower);
571 CONFIGFS_ATTR(gadget_config_desc_, bmAttributes);
572 
573 static struct configfs_attribute *gadget_config_attrs[] = {
574 	&gadget_config_desc_attr_MaxPower,
575 	&gadget_config_desc_attr_bmAttributes,
576 	NULL,
577 };
578 
579 static const struct config_item_type gadget_config_type = {
580 	.ct_item_ops	= &gadget_config_item_ops,
581 	.ct_attrs	= gadget_config_attrs,
582 	.ct_owner	= THIS_MODULE,
583 };
584 
585 static const struct config_item_type gadget_root_type = {
586 	.ct_item_ops	= &gadget_root_item_ops,
587 	.ct_attrs	= gadget_root_attrs,
588 	.ct_owner	= THIS_MODULE,
589 };
590 
591 static void composite_init_dev(struct usb_composite_dev *cdev)
592 {
593 	spin_lock_init(&cdev->lock);
594 	INIT_LIST_HEAD(&cdev->configs);
595 	INIT_LIST_HEAD(&cdev->gstrings);
596 }
597 
598 static struct config_group *function_make(
599 		struct config_group *group,
600 		const char *name)
601 {
602 	struct gadget_info *gi;
603 	struct usb_function_instance *fi;
604 	char buf[MAX_NAME_LEN];
605 	char *func_name;
606 	char *instance_name;
607 	int ret;
608 
609 	if (strlen(name) >= MAX_NAME_LEN)
610 		return ERR_PTR(-ENAMETOOLONG);
611 
612 	scnprintf(buf, MAX_NAME_LEN, "%s", name);
613 
614 	func_name = buf;
615 	instance_name = strchr(func_name, '.');
616 	if (!instance_name) {
617 		pr_err("Unable to locate . in FUNC.INSTANCE\n");
618 		return ERR_PTR(-EINVAL);
619 	}
620 	*instance_name = '\0';
621 	instance_name++;
622 
623 	fi = usb_get_function_instance(func_name);
624 	if (IS_ERR(fi))
625 		return ERR_CAST(fi);
626 
627 	ret = config_item_set_name(&fi->group.cg_item, "%s", name);
628 	if (ret) {
629 		usb_put_function_instance(fi);
630 		return ERR_PTR(ret);
631 	}
632 	if (fi->set_inst_name) {
633 		ret = fi->set_inst_name(fi, instance_name);
634 		if (ret) {
635 			usb_put_function_instance(fi);
636 			return ERR_PTR(ret);
637 		}
638 	}
639 
640 	gi = container_of(group, struct gadget_info, functions_group);
641 
642 	mutex_lock(&gi->lock);
643 	list_add_tail(&fi->cfs_list, &gi->available_func);
644 	mutex_unlock(&gi->lock);
645 	return &fi->group;
646 }
647 
648 static void function_drop(
649 		struct config_group *group,
650 		struct config_item *item)
651 {
652 	struct usb_function_instance *fi = to_usb_function_instance(item);
653 	struct gadget_info *gi;
654 
655 	gi = container_of(group, struct gadget_info, functions_group);
656 
657 	mutex_lock(&gi->lock);
658 	list_del(&fi->cfs_list);
659 	mutex_unlock(&gi->lock);
660 	config_item_put(item);
661 }
662 
663 static struct configfs_group_operations functions_ops = {
664 	.make_group     = &function_make,
665 	.drop_item      = &function_drop,
666 };
667 
668 static const struct config_item_type functions_type = {
669 	.ct_group_ops   = &functions_ops,
670 	.ct_owner       = THIS_MODULE,
671 };
672 
673 GS_STRINGS_RW(gadget_config_name, configuration);
674 
675 static struct configfs_attribute *gadget_config_name_langid_attrs[] = {
676 	&gadget_config_name_attr_configuration,
677 	NULL,
678 };
679 
680 static void gadget_config_name_attr_release(struct config_item *item)
681 {
682 	struct gadget_config_name *cn = to_gadget_config_name(item);
683 
684 	kfree(cn->configuration);
685 
686 	list_del(&cn->list);
687 	kfree(cn);
688 }
689 
690 USB_CONFIG_STRING_RW_OPS(gadget_config_name);
691 USB_CONFIG_STRINGS_LANG(gadget_config_name, config_usb_cfg);
692 
693 static struct config_group *config_desc_make(
694 		struct config_group *group,
695 		const char *name)
696 {
697 	struct gadget_info *gi;
698 	struct config_usb_cfg *cfg;
699 	char buf[MAX_NAME_LEN];
700 	char *num_str;
701 	u8 num;
702 	int ret;
703 
704 	gi = container_of(group, struct gadget_info, configs_group);
705 
706 	if (strlen(name) >= MAX_NAME_LEN)
707 		return ERR_PTR(-ENAMETOOLONG);
708 
709 	scnprintf(buf, MAX_NAME_LEN, "%s", name);
710 
711 	num_str = strchr(buf, '.');
712 	if (!num_str) {
713 		pr_err("Unable to locate . in name.bConfigurationValue\n");
714 		return ERR_PTR(-EINVAL);
715 	}
716 
717 	*num_str = '\0';
718 	num_str++;
719 
720 	if (!strlen(buf))
721 		return ERR_PTR(-EINVAL);
722 
723 	ret = kstrtou8(num_str, 0, &num);
724 	if (ret)
725 		return ERR_PTR(ret);
726 
727 	cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
728 	if (!cfg)
729 		return ERR_PTR(-ENOMEM);
730 	cfg->c.label = kstrdup(buf, GFP_KERNEL);
731 	if (!cfg->c.label) {
732 		ret = -ENOMEM;
733 		goto err;
734 	}
735 	cfg->c.bConfigurationValue = num;
736 	cfg->c.MaxPower = CONFIG_USB_GADGET_VBUS_DRAW;
737 	cfg->c.bmAttributes = USB_CONFIG_ATT_ONE;
738 	INIT_LIST_HEAD(&cfg->string_list);
739 	INIT_LIST_HEAD(&cfg->func_list);
740 
741 	config_group_init_type_name(&cfg->group, name,
742 				&gadget_config_type);
743 
744 	config_group_init_type_name(&cfg->strings_group, "strings",
745 			&gadget_config_name_strings_type);
746 	configfs_add_default_group(&cfg->strings_group, &cfg->group);
747 
748 	ret = usb_add_config_only(&gi->cdev, &cfg->c);
749 	if (ret)
750 		goto err;
751 
752 	return &cfg->group;
753 err:
754 	kfree(cfg->c.label);
755 	kfree(cfg);
756 	return ERR_PTR(ret);
757 }
758 
759 static void config_desc_drop(
760 		struct config_group *group,
761 		struct config_item *item)
762 {
763 	config_item_put(item);
764 }
765 
766 static struct configfs_group_operations config_desc_ops = {
767 	.make_group     = &config_desc_make,
768 	.drop_item      = &config_desc_drop,
769 };
770 
771 static const struct config_item_type config_desc_type = {
772 	.ct_group_ops   = &config_desc_ops,
773 	.ct_owner       = THIS_MODULE,
774 };
775 
776 GS_STRINGS_RW(gadget_language, manufacturer);
777 GS_STRINGS_RW(gadget_language, product);
778 GS_STRINGS_RW(gadget_language, serialnumber);
779 
780 static struct configfs_attribute *gadget_language_langid_attrs[] = {
781 	&gadget_language_attr_manufacturer,
782 	&gadget_language_attr_product,
783 	&gadget_language_attr_serialnumber,
784 	NULL,
785 };
786 
787 static void gadget_language_attr_release(struct config_item *item)
788 {
789 	struct gadget_language *gs = to_gadget_language(item);
790 
791 	kfree(gs->manufacturer);
792 	kfree(gs->product);
793 	kfree(gs->serialnumber);
794 
795 	list_del(&gs->list);
796 	kfree(gs);
797 }
798 
799 static struct configfs_item_operations gadget_language_langid_item_ops = {
800 	.release                = gadget_language_attr_release,
801 };
802 
803 static ssize_t gadget_string_id_show(struct config_item *item, char *page)
804 {
805 	struct gadget_string *string = to_gadget_string(item);
806 	int ret;
807 
808 	ret = sprintf(page, "%u\n", string->usb_string.id);
809 	return ret;
810 }
811 CONFIGFS_ATTR_RO(gadget_string_, id);
812 
813 static ssize_t gadget_string_s_show(struct config_item *item, char *page)
814 {
815 	struct gadget_string *string = to_gadget_string(item);
816 	int ret;
817 
818 	ret = sysfs_emit(page, "%s\n", string->string);
819 	return ret;
820 }
821 
822 static ssize_t gadget_string_s_store(struct config_item *item, const char *page,
823 				     size_t len)
824 {
825 	struct gadget_string *string = to_gadget_string(item);
826 	int size = min(sizeof(string->string), len + 1);
827 
828 	if (len > USB_MAX_STRING_LEN)
829 		return -EINVAL;
830 
831 	return strscpy(string->string, page, size);
832 }
833 CONFIGFS_ATTR(gadget_string_, s);
834 
835 static struct configfs_attribute *gadget_string_attrs[] = {
836 	&gadget_string_attr_id,
837 	&gadget_string_attr_s,
838 	NULL,
839 };
840 
841 static void gadget_string_release(struct config_item *item)
842 {
843 	struct gadget_string *string = to_gadget_string(item);
844 
845 	kfree(string);
846 }
847 
848 static struct configfs_item_operations gadget_string_item_ops = {
849 	.release	= gadget_string_release,
850 };
851 
852 static const struct config_item_type gadget_string_type = {
853 	.ct_item_ops	= &gadget_string_item_ops,
854 	.ct_attrs	= gadget_string_attrs,
855 	.ct_owner	= THIS_MODULE,
856 };
857 
858 static struct config_item *gadget_language_string_make(struct config_group *group,
859 						       const char *name)
860 {
861 	struct gadget_language *language;
862 	struct gadget_string *string;
863 
864 	language = to_gadget_language(&group->cg_item);
865 
866 	string = kzalloc(sizeof(*string), GFP_KERNEL);
867 	if (!string)
868 		return ERR_PTR(-ENOMEM);
869 
870 	string->usb_string.id = language->nstrings++;
871 	string->usb_string.s = string->string;
872 	list_add_tail(&string->list, &language->gadget_strings);
873 
874 	config_item_init_type_name(&string->item, name, &gadget_string_type);
875 
876 	return &string->item;
877 }
878 
879 static void gadget_language_string_drop(struct config_group *group,
880 					struct config_item *item)
881 {
882 	struct gadget_language *language;
883 	struct gadget_string *string;
884 	unsigned int i = USB_GADGET_FIRST_AVAIL_IDX;
885 
886 	language = to_gadget_language(&group->cg_item);
887 	string = to_gadget_string(item);
888 
889 	list_del(&string->list);
890 	language->nstrings--;
891 
892 	/* Reset the ids for the language's strings to guarantee a continuous set */
893 	list_for_each_entry(string, &language->gadget_strings, list)
894 		string->usb_string.id = i++;
895 }
896 
897 static struct configfs_group_operations gadget_language_langid_group_ops = {
898 	.make_item		= gadget_language_string_make,
899 	.drop_item		= gadget_language_string_drop,
900 };
901 
902 static struct config_item_type gadget_language_type = {
903 	.ct_item_ops	= &gadget_language_langid_item_ops,
904 	.ct_group_ops	= &gadget_language_langid_group_ops,
905 	.ct_attrs	= gadget_language_langid_attrs,
906 	.ct_owner	= THIS_MODULE,
907 };
908 
909 static struct config_group *gadget_language_make(struct config_group *group,
910 						 const char *name)
911 {
912 	struct gadget_info *gi;
913 	struct gadget_language *gs;
914 	struct gadget_language *new;
915 	int langs = 0;
916 	int ret;
917 
918 	new = kzalloc(sizeof(*new), GFP_KERNEL);
919 	if (!new)
920 		return ERR_PTR(-ENOMEM);
921 
922 	ret = check_user_usb_string(name, &new->stringtab_dev);
923 	if (ret)
924 		goto err;
925 	config_group_init_type_name(&new->group, name,
926 				    &gadget_language_type);
927 
928 	gi = container_of(group, struct gadget_info, strings_group);
929 	ret = -EEXIST;
930 	list_for_each_entry(gs, &gi->string_list, list) {
931 		if (gs->stringtab_dev.language == new->stringtab_dev.language)
932 			goto err;
933 		langs++;
934 	}
935 	ret = -EOVERFLOW;
936 	if (langs >= MAX_USB_STRING_LANGS)
937 		goto err;
938 
939 	list_add_tail(&new->list, &gi->string_list);
940 	INIT_LIST_HEAD(&new->gadget_strings);
941 
942 	/* We have the default manufacturer, product and serialnumber strings */
943 	new->nstrings = 3;
944 	return &new->group;
945 err:
946 	kfree(new);
947 	return ERR_PTR(ret);
948 }
949 
950 static void gadget_language_drop(struct config_group *group,
951 				 struct config_item *item)
952 {
953 	config_item_put(item);
954 }
955 
956 static struct configfs_group_operations gadget_language_group_ops = {
957 	.make_group     = &gadget_language_make,
958 	.drop_item      = &gadget_language_drop,
959 };
960 
961 static struct config_item_type gadget_language_strings_type = {
962 	.ct_group_ops   = &gadget_language_group_ops,
963 	.ct_owner       = THIS_MODULE,
964 };
965 
966 static inline struct gadget_info *webusb_item_to_gadget_info(
967 		struct config_item *item)
968 {
969 	return container_of(to_config_group(item),
970 			struct gadget_info, webusb_group);
971 }
972 
973 static ssize_t webusb_use_show(struct config_item *item, char *page)
974 {
975 	return sysfs_emit(page, "%d\n",
976 			webusb_item_to_gadget_info(item)->use_webusb);
977 }
978 
979 static ssize_t webusb_use_store(struct config_item *item, const char *page,
980 				 size_t len)
981 {
982 	struct gadget_info *gi = webusb_item_to_gadget_info(item);
983 	int ret;
984 	bool use;
985 
986 	ret = kstrtobool(page, &use);
987 	if (ret)
988 		return ret;
989 
990 	mutex_lock(&gi->lock);
991 	gi->use_webusb = use;
992 	mutex_unlock(&gi->lock);
993 
994 	return len;
995 }
996 
997 static ssize_t webusb_bcdVersion_show(struct config_item *item, char *page)
998 {
999 	return sysfs_emit(page, "0x%04x\n",
1000 					webusb_item_to_gadget_info(item)->bcd_webusb_version);
1001 }
1002 
1003 static ssize_t webusb_bcdVersion_store(struct config_item *item,
1004 		const char *page, size_t len)
1005 {
1006 	struct gadget_info *gi = webusb_item_to_gadget_info(item);
1007 	u16 bcdVersion;
1008 	int ret;
1009 
1010 	ret = kstrtou16(page, 0, &bcdVersion);
1011 	if (ret)
1012 		return ret;
1013 
1014 	ret = is_valid_bcd(bcdVersion);
1015 	if (ret)
1016 		return ret;
1017 
1018 	mutex_lock(&gi->lock);
1019 	gi->bcd_webusb_version = bcdVersion;
1020 	mutex_unlock(&gi->lock);
1021 
1022 	return len;
1023 }
1024 
1025 static ssize_t webusb_bVendorCode_show(struct config_item *item, char *page)
1026 {
1027 	return sysfs_emit(page, "0x%02x\n",
1028 			webusb_item_to_gadget_info(item)->b_webusb_vendor_code);
1029 }
1030 
1031 static ssize_t webusb_bVendorCode_store(struct config_item *item,
1032 					   const char *page, size_t len)
1033 {
1034 	struct gadget_info *gi = webusb_item_to_gadget_info(item);
1035 	int ret;
1036 	u8 b_vendor_code;
1037 
1038 	ret = kstrtou8(page, 0, &b_vendor_code);
1039 	if (ret)
1040 		return ret;
1041 
1042 	mutex_lock(&gi->lock);
1043 	gi->b_webusb_vendor_code = b_vendor_code;
1044 	mutex_unlock(&gi->lock);
1045 
1046 	return len;
1047 }
1048 
1049 static ssize_t webusb_landingPage_show(struct config_item *item, char *page)
1050 {
1051 	return sysfs_emit(page, "%s\n", webusb_item_to_gadget_info(item)->landing_page);
1052 }
1053 
1054 static ssize_t webusb_landingPage_store(struct config_item *item, const char *page,
1055 				     size_t len)
1056 {
1057 	struct gadget_info *gi = webusb_item_to_gadget_info(item);
1058 	unsigned int bytes_to_strip = 0;
1059 	int l = len;
1060 
1061 	if (page[l - 1] == '\n') {
1062 		--l;
1063 		++bytes_to_strip;
1064 	}
1065 
1066 	if (l > sizeof(gi->landing_page)) {
1067 		pr_err("webusb: landingPage URL too long\n");
1068 		return -EINVAL;
1069 	}
1070 
1071 	// validation
1072 	if (strncasecmp(page, "https://",  8) == 0)
1073 		bytes_to_strip = 8;
1074 	else if (strncasecmp(page, "http://", 7) == 0)
1075 		bytes_to_strip = 7;
1076 	else
1077 		bytes_to_strip = 0;
1078 
1079 	if (l > U8_MAX - WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + bytes_to_strip) {
1080 		pr_err("webusb: landingPage URL %d bytes too long for given URL scheme\n",
1081 			l - U8_MAX + WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH - bytes_to_strip);
1082 		return -EINVAL;
1083 	}
1084 
1085 	mutex_lock(&gi->lock);
1086 	// ensure 0 bytes are set, in case the new landing page is shorter then the old one.
1087 	memcpy_and_pad(gi->landing_page, sizeof(gi->landing_page), page, l, 0);
1088 	mutex_unlock(&gi->lock);
1089 
1090 	return len;
1091 }
1092 
1093 CONFIGFS_ATTR(webusb_, use);
1094 CONFIGFS_ATTR(webusb_, bVendorCode);
1095 CONFIGFS_ATTR(webusb_, bcdVersion);
1096 CONFIGFS_ATTR(webusb_, landingPage);
1097 
1098 static struct configfs_attribute *webusb_attrs[] = {
1099 	&webusb_attr_use,
1100 	&webusb_attr_bcdVersion,
1101 	&webusb_attr_bVendorCode,
1102 	&webusb_attr_landingPage,
1103 	NULL,
1104 };
1105 
1106 static struct config_item_type webusb_type = {
1107 	.ct_attrs	= webusb_attrs,
1108 	.ct_owner	= THIS_MODULE,
1109 };
1110 
1111 static inline struct gadget_info *os_desc_item_to_gadget_info(
1112 		struct config_item *item)
1113 {
1114 	return container_of(to_config_group(item),
1115 			struct gadget_info, os_desc_group);
1116 }
1117 
1118 static ssize_t os_desc_use_show(struct config_item *item, char *page)
1119 {
1120 	return sprintf(page, "%d\n",
1121 			os_desc_item_to_gadget_info(item)->use_os_desc);
1122 }
1123 
1124 static ssize_t os_desc_use_store(struct config_item *item, const char *page,
1125 				 size_t len)
1126 {
1127 	struct gadget_info *gi = os_desc_item_to_gadget_info(item);
1128 	int ret;
1129 	bool use;
1130 
1131 	ret = kstrtobool(page, &use);
1132 	if (ret)
1133 		return ret;
1134 
1135 	mutex_lock(&gi->lock);
1136 	gi->use_os_desc = use;
1137 	mutex_unlock(&gi->lock);
1138 
1139 	return len;
1140 }
1141 
1142 static ssize_t os_desc_b_vendor_code_show(struct config_item *item, char *page)
1143 {
1144 	return sprintf(page, "0x%02x\n",
1145 			os_desc_item_to_gadget_info(item)->b_vendor_code);
1146 }
1147 
1148 static ssize_t os_desc_b_vendor_code_store(struct config_item *item,
1149 					   const char *page, size_t len)
1150 {
1151 	struct gadget_info *gi = os_desc_item_to_gadget_info(item);
1152 	int ret;
1153 	u8 b_vendor_code;
1154 
1155 	ret = kstrtou8(page, 0, &b_vendor_code);
1156 	if (ret)
1157 		return ret;
1158 
1159 	mutex_lock(&gi->lock);
1160 	gi->b_vendor_code = b_vendor_code;
1161 	mutex_unlock(&gi->lock);
1162 
1163 	return len;
1164 }
1165 
1166 static ssize_t os_desc_qw_sign_show(struct config_item *item, char *page)
1167 {
1168 	struct gadget_info *gi = os_desc_item_to_gadget_info(item);
1169 	int res;
1170 
1171 	res = utf16s_to_utf8s((wchar_t *) gi->qw_sign, OS_STRING_QW_SIGN_LEN,
1172 			      UTF16_LITTLE_ENDIAN, page, PAGE_SIZE - 1);
1173 	page[res++] = '\n';
1174 
1175 	return res;
1176 }
1177 
1178 static ssize_t os_desc_qw_sign_store(struct config_item *item, const char *page,
1179 				     size_t len)
1180 {
1181 	struct gadget_info *gi = os_desc_item_to_gadget_info(item);
1182 	int res, l;
1183 
1184 	l = min((int)len, OS_STRING_QW_SIGN_LEN >> 1);
1185 	if (page[l - 1] == '\n')
1186 		--l;
1187 
1188 	mutex_lock(&gi->lock);
1189 	res = utf8s_to_utf16s(page, l,
1190 			      UTF16_LITTLE_ENDIAN, (wchar_t *) gi->qw_sign,
1191 			      OS_STRING_QW_SIGN_LEN);
1192 	if (res > 0)
1193 		res = len;
1194 	mutex_unlock(&gi->lock);
1195 
1196 	return res;
1197 }
1198 
1199 CONFIGFS_ATTR(os_desc_, use);
1200 CONFIGFS_ATTR(os_desc_, b_vendor_code);
1201 CONFIGFS_ATTR(os_desc_, qw_sign);
1202 
1203 static struct configfs_attribute *os_desc_attrs[] = {
1204 	&os_desc_attr_use,
1205 	&os_desc_attr_b_vendor_code,
1206 	&os_desc_attr_qw_sign,
1207 	NULL,
1208 };
1209 
1210 static int os_desc_link(struct config_item *os_desc_ci,
1211 			struct config_item *usb_cfg_ci)
1212 {
1213 	struct gadget_info *gi = os_desc_item_to_gadget_info(os_desc_ci);
1214 	struct usb_composite_dev *cdev = &gi->cdev;
1215 	struct config_usb_cfg *c_target = to_config_usb_cfg(usb_cfg_ci);
1216 	struct usb_configuration *c = NULL, *iter;
1217 	int ret;
1218 
1219 	mutex_lock(&gi->lock);
1220 	list_for_each_entry(iter, &cdev->configs, list) {
1221 		if (iter != &c_target->c)
1222 			continue;
1223 		c = iter;
1224 		break;
1225 	}
1226 	if (!c) {
1227 		ret = -EINVAL;
1228 		goto out;
1229 	}
1230 
1231 	if (cdev->os_desc_config) {
1232 		ret = -EBUSY;
1233 		goto out;
1234 	}
1235 
1236 	cdev->os_desc_config = &c_target->c;
1237 	ret = 0;
1238 
1239 out:
1240 	mutex_unlock(&gi->lock);
1241 	return ret;
1242 }
1243 
1244 static void os_desc_unlink(struct config_item *os_desc_ci,
1245 			  struct config_item *usb_cfg_ci)
1246 {
1247 	struct gadget_info *gi = os_desc_item_to_gadget_info(os_desc_ci);
1248 	struct usb_composite_dev *cdev = &gi->cdev;
1249 
1250 	mutex_lock(&gi->lock);
1251 	if (gi->composite.gadget_driver.udc_name)
1252 		unregister_gadget(gi);
1253 	cdev->os_desc_config = NULL;
1254 	WARN_ON(gi->composite.gadget_driver.udc_name);
1255 	mutex_unlock(&gi->lock);
1256 }
1257 
1258 static struct configfs_item_operations os_desc_ops = {
1259 	.allow_link		= os_desc_link,
1260 	.drop_link		= os_desc_unlink,
1261 };
1262 
1263 static struct config_item_type os_desc_type = {
1264 	.ct_item_ops	= &os_desc_ops,
1265 	.ct_attrs	= os_desc_attrs,
1266 	.ct_owner	= THIS_MODULE,
1267 };
1268 
1269 static inline struct usb_os_desc_ext_prop
1270 *to_usb_os_desc_ext_prop(struct config_item *item)
1271 {
1272 	return container_of(item, struct usb_os_desc_ext_prop, item);
1273 }
1274 
1275 static ssize_t ext_prop_type_show(struct config_item *item, char *page)
1276 {
1277 	return sprintf(page, "%d\n", to_usb_os_desc_ext_prop(item)->type);
1278 }
1279 
1280 static ssize_t ext_prop_type_store(struct config_item *item,
1281 				   const char *page, size_t len)
1282 {
1283 	struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1284 	struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
1285 	u8 type;
1286 	int ret;
1287 
1288 	ret = kstrtou8(page, 0, &type);
1289 	if (ret)
1290 		return ret;
1291 
1292 	if (type < USB_EXT_PROP_UNICODE || type > USB_EXT_PROP_UNICODE_MULTI)
1293 		return -EINVAL;
1294 
1295 	if (desc->opts_mutex)
1296 		mutex_lock(desc->opts_mutex);
1297 
1298 	if ((ext_prop->type == USB_EXT_PROP_BINARY ||
1299 	    ext_prop->type == USB_EXT_PROP_LE32 ||
1300 	    ext_prop->type == USB_EXT_PROP_BE32) &&
1301 	    (type == USB_EXT_PROP_UNICODE ||
1302 	    type == USB_EXT_PROP_UNICODE_ENV ||
1303 	    type == USB_EXT_PROP_UNICODE_LINK))
1304 		ext_prop->data_len <<= 1;
1305 	else if ((ext_prop->type == USB_EXT_PROP_UNICODE ||
1306 		   ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
1307 		   ext_prop->type == USB_EXT_PROP_UNICODE_LINK) &&
1308 		   (type == USB_EXT_PROP_BINARY ||
1309 		   type == USB_EXT_PROP_LE32 ||
1310 		   type == USB_EXT_PROP_BE32))
1311 		ext_prop->data_len >>= 1;
1312 	ext_prop->type = type;
1313 
1314 	if (desc->opts_mutex)
1315 		mutex_unlock(desc->opts_mutex);
1316 	return len;
1317 }
1318 
1319 static ssize_t ext_prop_data_show(struct config_item *item, char *page)
1320 {
1321 	struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1322 	int len = ext_prop->data_len;
1323 
1324 	if (ext_prop->type == USB_EXT_PROP_UNICODE ||
1325 	    ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
1326 	    ext_prop->type == USB_EXT_PROP_UNICODE_LINK)
1327 		len >>= 1;
1328 	memcpy(page, ext_prop->data, len);
1329 
1330 	return len;
1331 }
1332 
1333 static ssize_t ext_prop_data_store(struct config_item *item,
1334 				   const char *page, size_t len)
1335 {
1336 	struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1337 	struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
1338 	char *new_data;
1339 	size_t ret_len = len;
1340 
1341 	if (page[len - 1] == '\n' || page[len - 1] == '\0')
1342 		--len;
1343 	new_data = kmemdup(page, len, GFP_KERNEL);
1344 	if (!new_data)
1345 		return -ENOMEM;
1346 
1347 	if (desc->opts_mutex)
1348 		mutex_lock(desc->opts_mutex);
1349 	kfree(ext_prop->data);
1350 	ext_prop->data = new_data;
1351 	desc->ext_prop_len -= ext_prop->data_len;
1352 	ext_prop->data_len = len;
1353 	desc->ext_prop_len += ext_prop->data_len;
1354 	if (ext_prop->type == USB_EXT_PROP_UNICODE ||
1355 	    ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
1356 	    ext_prop->type == USB_EXT_PROP_UNICODE_LINK) {
1357 		desc->ext_prop_len -= ext_prop->data_len;
1358 		ext_prop->data_len <<= 1;
1359 		ext_prop->data_len += 2;
1360 		desc->ext_prop_len += ext_prop->data_len;
1361 	}
1362 	if (desc->opts_mutex)
1363 		mutex_unlock(desc->opts_mutex);
1364 	return ret_len;
1365 }
1366 
1367 CONFIGFS_ATTR(ext_prop_, type);
1368 CONFIGFS_ATTR(ext_prop_, data);
1369 
1370 static struct configfs_attribute *ext_prop_attrs[] = {
1371 	&ext_prop_attr_type,
1372 	&ext_prop_attr_data,
1373 	NULL,
1374 };
1375 
1376 static void usb_os_desc_ext_prop_release(struct config_item *item)
1377 {
1378 	struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1379 
1380 	kfree(ext_prop); /* frees a whole chunk */
1381 }
1382 
1383 static struct configfs_item_operations ext_prop_ops = {
1384 	.release		= usb_os_desc_ext_prop_release,
1385 };
1386 
1387 static struct config_item *ext_prop_make(
1388 		struct config_group *group,
1389 		const char *name)
1390 {
1391 	struct usb_os_desc_ext_prop *ext_prop;
1392 	struct config_item_type *ext_prop_type;
1393 	struct usb_os_desc *desc;
1394 	char *vlabuf;
1395 
1396 	vla_group(data_chunk);
1397 	vla_item(data_chunk, struct usb_os_desc_ext_prop, ext_prop, 1);
1398 	vla_item(data_chunk, struct config_item_type, ext_prop_type, 1);
1399 
1400 	vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1401 	if (!vlabuf)
1402 		return ERR_PTR(-ENOMEM);
1403 
1404 	ext_prop = vla_ptr(vlabuf, data_chunk, ext_prop);
1405 	ext_prop_type = vla_ptr(vlabuf, data_chunk, ext_prop_type);
1406 
1407 	desc = container_of(group, struct usb_os_desc, group);
1408 	ext_prop_type->ct_item_ops = &ext_prop_ops;
1409 	ext_prop_type->ct_attrs = ext_prop_attrs;
1410 	ext_prop_type->ct_owner = desc->owner;
1411 
1412 	config_item_init_type_name(&ext_prop->item, name, ext_prop_type);
1413 
1414 	ext_prop->name = kstrdup(name, GFP_KERNEL);
1415 	if (!ext_prop->name) {
1416 		kfree(vlabuf);
1417 		return ERR_PTR(-ENOMEM);
1418 	}
1419 	desc->ext_prop_len += 14;
1420 	ext_prop->name_len = 2 * strlen(ext_prop->name) + 2;
1421 	if (desc->opts_mutex)
1422 		mutex_lock(desc->opts_mutex);
1423 	desc->ext_prop_len += ext_prop->name_len;
1424 	list_add_tail(&ext_prop->entry, &desc->ext_prop);
1425 	++desc->ext_prop_count;
1426 	if (desc->opts_mutex)
1427 		mutex_unlock(desc->opts_mutex);
1428 
1429 	return &ext_prop->item;
1430 }
1431 
1432 static void ext_prop_drop(struct config_group *group, struct config_item *item)
1433 {
1434 	struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1435 	struct usb_os_desc *desc = to_usb_os_desc(&group->cg_item);
1436 
1437 	if (desc->opts_mutex)
1438 		mutex_lock(desc->opts_mutex);
1439 	list_del(&ext_prop->entry);
1440 	--desc->ext_prop_count;
1441 	kfree(ext_prop->name);
1442 	desc->ext_prop_len -= (ext_prop->name_len + ext_prop->data_len + 14);
1443 	if (desc->opts_mutex)
1444 		mutex_unlock(desc->opts_mutex);
1445 	config_item_put(item);
1446 }
1447 
1448 static struct configfs_group_operations interf_grp_ops = {
1449 	.make_item	= &ext_prop_make,
1450 	.drop_item	= &ext_prop_drop,
1451 };
1452 
1453 static ssize_t interf_grp_compatible_id_show(struct config_item *item,
1454 					     char *page)
1455 {
1456 	memcpy(page, to_usb_os_desc(item)->ext_compat_id, 8);
1457 	return 8;
1458 }
1459 
1460 static ssize_t interf_grp_compatible_id_store(struct config_item *item,
1461 					      const char *page, size_t len)
1462 {
1463 	struct usb_os_desc *desc = to_usb_os_desc(item);
1464 	int l;
1465 
1466 	l = min_t(int, 8, len);
1467 	if (page[l - 1] == '\n')
1468 		--l;
1469 	if (desc->opts_mutex)
1470 		mutex_lock(desc->opts_mutex);
1471 	memcpy(desc->ext_compat_id, page, l);
1472 
1473 	if (desc->opts_mutex)
1474 		mutex_unlock(desc->opts_mutex);
1475 
1476 	return len;
1477 }
1478 
1479 static ssize_t interf_grp_sub_compatible_id_show(struct config_item *item,
1480 						 char *page)
1481 {
1482 	memcpy(page, to_usb_os_desc(item)->ext_compat_id + 8, 8);
1483 	return 8;
1484 }
1485 
1486 static ssize_t interf_grp_sub_compatible_id_store(struct config_item *item,
1487 						  const char *page, size_t len)
1488 {
1489 	struct usb_os_desc *desc = to_usb_os_desc(item);
1490 	int l;
1491 
1492 	l = min_t(int, 8, len);
1493 	if (page[l - 1] == '\n')
1494 		--l;
1495 	if (desc->opts_mutex)
1496 		mutex_lock(desc->opts_mutex);
1497 	memcpy(desc->ext_compat_id + 8, page, l);
1498 
1499 	if (desc->opts_mutex)
1500 		mutex_unlock(desc->opts_mutex);
1501 
1502 	return len;
1503 }
1504 
1505 CONFIGFS_ATTR(interf_grp_, compatible_id);
1506 CONFIGFS_ATTR(interf_grp_, sub_compatible_id);
1507 
1508 static struct configfs_attribute *interf_grp_attrs[] = {
1509 	&interf_grp_attr_compatible_id,
1510 	&interf_grp_attr_sub_compatible_id,
1511 	NULL
1512 };
1513 
1514 struct config_group *usb_os_desc_prepare_interf_dir(
1515 		struct config_group *parent,
1516 		int n_interf,
1517 		struct usb_os_desc **desc,
1518 		char **names,
1519 		struct module *owner)
1520 {
1521 	struct config_group *os_desc_group;
1522 	struct config_item_type *os_desc_type, *interface_type;
1523 
1524 	vla_group(data_chunk);
1525 	vla_item(data_chunk, struct config_group, os_desc_group, 1);
1526 	vla_item(data_chunk, struct config_item_type, os_desc_type, 1);
1527 	vla_item(data_chunk, struct config_item_type, interface_type, 1);
1528 
1529 	char *vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1530 	if (!vlabuf)
1531 		return ERR_PTR(-ENOMEM);
1532 
1533 	os_desc_group = vla_ptr(vlabuf, data_chunk, os_desc_group);
1534 	os_desc_type = vla_ptr(vlabuf, data_chunk, os_desc_type);
1535 	interface_type = vla_ptr(vlabuf, data_chunk, interface_type);
1536 
1537 	os_desc_type->ct_owner = owner;
1538 	config_group_init_type_name(os_desc_group, "os_desc", os_desc_type);
1539 	configfs_add_default_group(os_desc_group, parent);
1540 
1541 	interface_type->ct_group_ops = &interf_grp_ops;
1542 	interface_type->ct_attrs = interf_grp_attrs;
1543 	interface_type->ct_owner = owner;
1544 
1545 	while (n_interf--) {
1546 		struct usb_os_desc *d;
1547 
1548 		d = desc[n_interf];
1549 		d->owner = owner;
1550 		config_group_init_type_name(&d->group, "", interface_type);
1551 		config_item_set_name(&d->group.cg_item, "interface.%s",
1552 				     names[n_interf]);
1553 		configfs_add_default_group(&d->group, os_desc_group);
1554 	}
1555 
1556 	return os_desc_group;
1557 }
1558 EXPORT_SYMBOL(usb_os_desc_prepare_interf_dir);
1559 
1560 static int configfs_do_nothing(struct usb_composite_dev *cdev)
1561 {
1562 	WARN_ON(1);
1563 	return -EINVAL;
1564 }
1565 
1566 int composite_dev_prepare(struct usb_composite_driver *composite,
1567 		struct usb_composite_dev *dev);
1568 
1569 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
1570 				  struct usb_ep *ep0);
1571 
1572 static void purge_configs_funcs(struct gadget_info *gi)
1573 {
1574 	struct usb_configuration	*c;
1575 
1576 	list_for_each_entry(c, &gi->cdev.configs, list) {
1577 		struct usb_function *f, *tmp;
1578 		struct config_usb_cfg *cfg;
1579 
1580 		cfg = container_of(c, struct config_usb_cfg, c);
1581 
1582 		list_for_each_entry_safe_reverse(f, tmp, &c->functions, list) {
1583 
1584 			list_move(&f->list, &cfg->func_list);
1585 			if (f->unbind) {
1586 				dev_dbg(&gi->cdev.gadget->dev,
1587 					"unbind function '%s'/%p\n",
1588 					f->name, f);
1589 				f->unbind(c, f);
1590 			}
1591 		}
1592 		c->next_interface_id = 0;
1593 		memset(c->interface, 0, sizeof(c->interface));
1594 		c->superspeed_plus = 0;
1595 		c->superspeed = 0;
1596 		c->highspeed = 0;
1597 		c->fullspeed = 0;
1598 	}
1599 }
1600 
1601 static struct usb_string *
1602 configfs_attach_gadget_strings(struct gadget_info *gi)
1603 {
1604 	struct usb_gadget_strings **gadget_strings;
1605 	struct gadget_language *language;
1606 	struct gadget_string *string;
1607 	unsigned int nlangs = 0;
1608 	struct list_head *iter;
1609 	struct usb_string *us;
1610 	unsigned int i = 0;
1611 	int nstrings = -1;
1612 	unsigned int j;
1613 
1614 	list_for_each(iter, &gi->string_list)
1615 		nlangs++;
1616 
1617 	/* Bail out early if no languages are configured */
1618 	if (!nlangs)
1619 		return NULL;
1620 
1621 	gadget_strings = kcalloc(nlangs + 1, /* including NULL terminator */
1622 				 sizeof(struct usb_gadget_strings *), GFP_KERNEL);
1623 	if (!gadget_strings)
1624 		return ERR_PTR(-ENOMEM);
1625 
1626 	list_for_each_entry(language, &gi->string_list, list) {
1627 		struct usb_string *stringtab;
1628 
1629 		if (nstrings == -1) {
1630 			nstrings = language->nstrings;
1631 		} else if (nstrings != language->nstrings) {
1632 			pr_err("languages must contain the same number of strings\n");
1633 			us = ERR_PTR(-EINVAL);
1634 			goto cleanup;
1635 		}
1636 
1637 		stringtab = kcalloc(language->nstrings + 1, sizeof(struct usb_string),
1638 				    GFP_KERNEL);
1639 		if (!stringtab) {
1640 			us = ERR_PTR(-ENOMEM);
1641 			goto cleanup;
1642 		}
1643 
1644 		stringtab[USB_GADGET_MANUFACTURER_IDX].id = USB_GADGET_MANUFACTURER_IDX;
1645 		stringtab[USB_GADGET_MANUFACTURER_IDX].s = language->manufacturer;
1646 		stringtab[USB_GADGET_PRODUCT_IDX].id = USB_GADGET_PRODUCT_IDX;
1647 		stringtab[USB_GADGET_PRODUCT_IDX].s = language->product;
1648 		stringtab[USB_GADGET_SERIAL_IDX].id = USB_GADGET_SERIAL_IDX;
1649 		stringtab[USB_GADGET_SERIAL_IDX].s = language->serialnumber;
1650 
1651 		j = USB_GADGET_FIRST_AVAIL_IDX;
1652 		list_for_each_entry(string, &language->gadget_strings, list) {
1653 			memcpy(&stringtab[j], &string->usb_string, sizeof(struct usb_string));
1654 			j++;
1655 		}
1656 
1657 		language->stringtab_dev.strings = stringtab;
1658 		gadget_strings[i] = &language->stringtab_dev;
1659 		i++;
1660 	}
1661 
1662 	us = usb_gstrings_attach(&gi->cdev, gadget_strings, nstrings);
1663 
1664 cleanup:
1665 	list_for_each_entry(language, &gi->string_list, list) {
1666 		kfree(language->stringtab_dev.strings);
1667 		language->stringtab_dev.strings = NULL;
1668 	}
1669 
1670 	kfree(gadget_strings);
1671 
1672 	return us;
1673 }
1674 
1675 static int configfs_composite_bind(struct usb_gadget *gadget,
1676 		struct usb_gadget_driver *gdriver)
1677 {
1678 	struct usb_composite_driver     *composite = to_cdriver(gdriver);
1679 	struct gadget_info		*gi = container_of(composite,
1680 						struct gadget_info, composite);
1681 	struct usb_composite_dev	*cdev = &gi->cdev;
1682 	struct usb_configuration	*c;
1683 	struct usb_string		*s;
1684 	unsigned			i;
1685 	int				ret;
1686 
1687 	/* the gi->lock is hold by the caller */
1688 	gi->unbind = 0;
1689 	cdev->gadget = gadget;
1690 	set_gadget_data(gadget, cdev);
1691 	ret = composite_dev_prepare(composite, cdev);
1692 	if (ret)
1693 		return ret;
1694 	/* and now the gadget bind */
1695 	ret = -EINVAL;
1696 
1697 	if (list_empty(&gi->cdev.configs)) {
1698 		pr_err("Need at least one configuration in %s.\n",
1699 				gi->composite.name);
1700 		goto err_comp_cleanup;
1701 	}
1702 
1703 
1704 	list_for_each_entry(c, &gi->cdev.configs, list) {
1705 		struct config_usb_cfg *cfg;
1706 
1707 		cfg = container_of(c, struct config_usb_cfg, c);
1708 		if (list_empty(&cfg->func_list)) {
1709 			pr_err("Config %s/%d of %s needs at least one function.\n",
1710 			      c->label, c->bConfigurationValue,
1711 			      gi->composite.name);
1712 			goto err_comp_cleanup;
1713 		}
1714 	}
1715 
1716 	/* init all strings */
1717 	if (!list_empty(&gi->string_list)) {
1718 		s = configfs_attach_gadget_strings(gi);
1719 		if (IS_ERR(s)) {
1720 			ret = PTR_ERR(s);
1721 			goto err_comp_cleanup;
1722 		}
1723 
1724 		gi->cdev.desc.iManufacturer = s[USB_GADGET_MANUFACTURER_IDX].id;
1725 		gi->cdev.desc.iProduct = s[USB_GADGET_PRODUCT_IDX].id;
1726 		gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
1727 
1728 		gi->cdev.usb_strings = s;
1729 	}
1730 
1731 	if (gi->use_webusb) {
1732 		cdev->use_webusb = true;
1733 		cdev->bcd_webusb_version = gi->bcd_webusb_version;
1734 		cdev->b_webusb_vendor_code = gi->b_webusb_vendor_code;
1735 		memcpy(cdev->landing_page, gi->landing_page, WEBUSB_URL_RAW_MAX_LENGTH);
1736 	}
1737 
1738 	if (gi->use_os_desc) {
1739 		cdev->use_os_string = true;
1740 		cdev->b_vendor_code = gi->b_vendor_code;
1741 		memcpy(cdev->qw_sign, gi->qw_sign, OS_STRING_QW_SIGN_LEN);
1742 	}
1743 
1744 	if (gadget_is_otg(gadget) && !otg_desc[0]) {
1745 		struct usb_descriptor_header *usb_desc;
1746 
1747 		usb_desc = usb_otg_descriptor_alloc(gadget);
1748 		if (!usb_desc) {
1749 			ret = -ENOMEM;
1750 			goto err_comp_cleanup;
1751 		}
1752 		usb_otg_descriptor_init(gadget, usb_desc);
1753 		otg_desc[0] = usb_desc;
1754 		otg_desc[1] = NULL;
1755 	}
1756 
1757 	/* Go through all configs, attach all functions */
1758 	list_for_each_entry(c, &gi->cdev.configs, list) {
1759 		struct config_usb_cfg *cfg;
1760 		struct usb_function *f;
1761 		struct usb_function *tmp;
1762 		struct gadget_config_name *cn;
1763 
1764 		if (gadget_is_otg(gadget))
1765 			c->descriptors = otg_desc;
1766 
1767 		/* Properly configure the bmAttributes wakeup bit */
1768 		check_remote_wakeup_config(gadget, c);
1769 
1770 		cfg = container_of(c, struct config_usb_cfg, c);
1771 		if (!list_empty(&cfg->string_list)) {
1772 			i = 0;
1773 			list_for_each_entry(cn, &cfg->string_list, list) {
1774 				cfg->gstrings[i] = &cn->stringtab_dev;
1775 				cn->stringtab_dev.strings = &cn->strings;
1776 				cn->strings.s = cn->configuration;
1777 				i++;
1778 			}
1779 			cfg->gstrings[i] = NULL;
1780 			s = usb_gstrings_attach(&gi->cdev, cfg->gstrings, 1);
1781 			if (IS_ERR(s)) {
1782 				ret = PTR_ERR(s);
1783 				goto err_comp_cleanup;
1784 			}
1785 			c->iConfiguration = s[0].id;
1786 		}
1787 
1788 		list_for_each_entry_safe(f, tmp, &cfg->func_list, list) {
1789 			list_del(&f->list);
1790 			ret = usb_add_function(c, f);
1791 			if (ret) {
1792 				list_add(&f->list, &cfg->func_list);
1793 				goto err_purge_funcs;
1794 			}
1795 		}
1796 		ret = usb_gadget_check_config(cdev->gadget);
1797 		if (ret)
1798 			goto err_purge_funcs;
1799 
1800 		usb_ep_autoconfig_reset(cdev->gadget);
1801 	}
1802 	if (cdev->use_os_string) {
1803 		ret = composite_os_desc_req_prepare(cdev, gadget->ep0);
1804 		if (ret)
1805 			goto err_purge_funcs;
1806 	}
1807 
1808 	usb_ep_autoconfig_reset(cdev->gadget);
1809 	return 0;
1810 
1811 err_purge_funcs:
1812 	purge_configs_funcs(gi);
1813 err_comp_cleanup:
1814 	composite_dev_cleanup(cdev);
1815 	return ret;
1816 }
1817 
1818 static void configfs_composite_unbind(struct usb_gadget *gadget)
1819 {
1820 	struct usb_composite_dev	*cdev;
1821 	struct gadget_info		*gi;
1822 	unsigned long flags;
1823 
1824 	/* the gi->lock is hold by the caller */
1825 
1826 	cdev = get_gadget_data(gadget);
1827 	gi = container_of(cdev, struct gadget_info, cdev);
1828 	spin_lock_irqsave(&gi->spinlock, flags);
1829 	gi->unbind = 1;
1830 	spin_unlock_irqrestore(&gi->spinlock, flags);
1831 
1832 	kfree(otg_desc[0]);
1833 	otg_desc[0] = NULL;
1834 	purge_configs_funcs(gi);
1835 	composite_dev_cleanup(cdev);
1836 	usb_ep_autoconfig_reset(cdev->gadget);
1837 	spin_lock_irqsave(&gi->spinlock, flags);
1838 	cdev->gadget = NULL;
1839 	cdev->deactivations = 0;
1840 	gadget->deactivated = false;
1841 	set_gadget_data(gadget, NULL);
1842 	spin_unlock_irqrestore(&gi->spinlock, flags);
1843 }
1844 
1845 static int configfs_composite_setup(struct usb_gadget *gadget,
1846 		const struct usb_ctrlrequest *ctrl)
1847 {
1848 	struct usb_composite_dev *cdev;
1849 	struct gadget_info *gi;
1850 	unsigned long flags;
1851 	int ret;
1852 
1853 	cdev = get_gadget_data(gadget);
1854 	if (!cdev)
1855 		return 0;
1856 
1857 	gi = container_of(cdev, struct gadget_info, cdev);
1858 	spin_lock_irqsave(&gi->spinlock, flags);
1859 	cdev = get_gadget_data(gadget);
1860 	if (!cdev || gi->unbind) {
1861 		spin_unlock_irqrestore(&gi->spinlock, flags);
1862 		return 0;
1863 	}
1864 
1865 	ret = composite_setup(gadget, ctrl);
1866 	spin_unlock_irqrestore(&gi->spinlock, flags);
1867 	return ret;
1868 }
1869 
1870 static void configfs_composite_disconnect(struct usb_gadget *gadget)
1871 {
1872 	struct usb_composite_dev *cdev;
1873 	struct gadget_info *gi;
1874 	unsigned long flags;
1875 
1876 	cdev = get_gadget_data(gadget);
1877 	if (!cdev)
1878 		return;
1879 
1880 	gi = container_of(cdev, struct gadget_info, cdev);
1881 	spin_lock_irqsave(&gi->spinlock, flags);
1882 	cdev = get_gadget_data(gadget);
1883 	if (!cdev || gi->unbind) {
1884 		spin_unlock_irqrestore(&gi->spinlock, flags);
1885 		return;
1886 	}
1887 
1888 	composite_disconnect(gadget);
1889 	spin_unlock_irqrestore(&gi->spinlock, flags);
1890 }
1891 
1892 static void configfs_composite_reset(struct usb_gadget *gadget)
1893 {
1894 	struct usb_composite_dev *cdev;
1895 	struct gadget_info *gi;
1896 	unsigned long flags;
1897 
1898 	cdev = get_gadget_data(gadget);
1899 	if (!cdev)
1900 		return;
1901 
1902 	gi = container_of(cdev, struct gadget_info, cdev);
1903 	spin_lock_irqsave(&gi->spinlock, flags);
1904 	cdev = get_gadget_data(gadget);
1905 	if (!cdev || gi->unbind) {
1906 		spin_unlock_irqrestore(&gi->spinlock, flags);
1907 		return;
1908 	}
1909 
1910 	composite_reset(gadget);
1911 	spin_unlock_irqrestore(&gi->spinlock, flags);
1912 }
1913 
1914 static void configfs_composite_suspend(struct usb_gadget *gadget)
1915 {
1916 	struct usb_composite_dev *cdev;
1917 	struct gadget_info *gi;
1918 	unsigned long flags;
1919 
1920 	cdev = get_gadget_data(gadget);
1921 	if (!cdev)
1922 		return;
1923 
1924 	gi = container_of(cdev, struct gadget_info, cdev);
1925 	spin_lock_irqsave(&gi->spinlock, flags);
1926 	cdev = get_gadget_data(gadget);
1927 	if (!cdev || gi->unbind) {
1928 		spin_unlock_irqrestore(&gi->spinlock, flags);
1929 		return;
1930 	}
1931 
1932 	composite_suspend(gadget);
1933 	spin_unlock_irqrestore(&gi->spinlock, flags);
1934 }
1935 
1936 static void configfs_composite_resume(struct usb_gadget *gadget)
1937 {
1938 	struct usb_composite_dev *cdev;
1939 	struct gadget_info *gi;
1940 	unsigned long flags;
1941 
1942 	cdev = get_gadget_data(gadget);
1943 	if (!cdev)
1944 		return;
1945 
1946 	gi = container_of(cdev, struct gadget_info, cdev);
1947 	spin_lock_irqsave(&gi->spinlock, flags);
1948 	cdev = get_gadget_data(gadget);
1949 	if (!cdev || gi->unbind) {
1950 		spin_unlock_irqrestore(&gi->spinlock, flags);
1951 		return;
1952 	}
1953 
1954 	composite_resume(gadget);
1955 	spin_unlock_irqrestore(&gi->spinlock, flags);
1956 }
1957 
1958 static const struct usb_gadget_driver configfs_driver_template = {
1959 	.bind           = configfs_composite_bind,
1960 	.unbind         = configfs_composite_unbind,
1961 
1962 	.setup          = configfs_composite_setup,
1963 	.reset          = configfs_composite_reset,
1964 	.disconnect     = configfs_composite_disconnect,
1965 
1966 	.suspend	= configfs_composite_suspend,
1967 	.resume		= configfs_composite_resume,
1968 
1969 	.max_speed	= USB_SPEED_SUPER_PLUS,
1970 	.driver = {
1971 		.owner          = THIS_MODULE,
1972 	},
1973 	.match_existing_only = 1,
1974 };
1975 
1976 static struct config_group *gadgets_make(
1977 		struct config_group *group,
1978 		const char *name)
1979 {
1980 	struct gadget_info *gi;
1981 
1982 	gi = kzalloc(sizeof(*gi), GFP_KERNEL);
1983 	if (!gi)
1984 		return ERR_PTR(-ENOMEM);
1985 
1986 	config_group_init_type_name(&gi->group, name, &gadget_root_type);
1987 
1988 	config_group_init_type_name(&gi->functions_group, "functions",
1989 			&functions_type);
1990 	configfs_add_default_group(&gi->functions_group, &gi->group);
1991 
1992 	config_group_init_type_name(&gi->configs_group, "configs",
1993 			&config_desc_type);
1994 	configfs_add_default_group(&gi->configs_group, &gi->group);
1995 
1996 	config_group_init_type_name(&gi->strings_group, "strings",
1997 			&gadget_language_strings_type);
1998 	configfs_add_default_group(&gi->strings_group, &gi->group);
1999 
2000 	config_group_init_type_name(&gi->os_desc_group, "os_desc",
2001 			&os_desc_type);
2002 	configfs_add_default_group(&gi->os_desc_group, &gi->group);
2003 
2004 	config_group_init_type_name(&gi->webusb_group, "webusb",
2005 			&webusb_type);
2006 	configfs_add_default_group(&gi->webusb_group, &gi->group);
2007 
2008 	gi->composite.bind = configfs_do_nothing;
2009 	gi->composite.unbind = configfs_do_nothing;
2010 	gi->composite.suspend = NULL;
2011 	gi->composite.resume = NULL;
2012 	gi->composite.max_speed = USB_SPEED_SUPER_PLUS;
2013 
2014 	spin_lock_init(&gi->spinlock);
2015 	mutex_init(&gi->lock);
2016 	INIT_LIST_HEAD(&gi->string_list);
2017 	INIT_LIST_HEAD(&gi->available_func);
2018 
2019 	composite_init_dev(&gi->cdev);
2020 	gi->cdev.desc.bLength = USB_DT_DEVICE_SIZE;
2021 	gi->cdev.desc.bDescriptorType = USB_DT_DEVICE;
2022 	gi->cdev.desc.bcdDevice = cpu_to_le16(get_default_bcdDevice());
2023 
2024 	gi->composite.gadget_driver = configfs_driver_template;
2025 
2026 	gi->composite.gadget_driver.driver.name = kasprintf(GFP_KERNEL,
2027 							    "configfs-gadget.%s", name);
2028 	if (!gi->composite.gadget_driver.driver.name)
2029 		goto err;
2030 
2031 	gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
2032 	gi->composite.name = gi->composite.gadget_driver.function;
2033 
2034 	if (!gi->composite.gadget_driver.function)
2035 		goto out_free_driver_name;
2036 
2037 	return &gi->group;
2038 
2039 out_free_driver_name:
2040 	kfree(gi->composite.gadget_driver.driver.name);
2041 err:
2042 	kfree(gi);
2043 	return ERR_PTR(-ENOMEM);
2044 }
2045 
2046 static void gadgets_drop(struct config_group *group, struct config_item *item)
2047 {
2048 	config_item_put(item);
2049 }
2050 
2051 static struct configfs_group_operations gadgets_ops = {
2052 	.make_group     = &gadgets_make,
2053 	.drop_item      = &gadgets_drop,
2054 };
2055 
2056 static const struct config_item_type gadgets_type = {
2057 	.ct_group_ops   = &gadgets_ops,
2058 	.ct_owner       = THIS_MODULE,
2059 };
2060 
2061 static struct configfs_subsystem gadget_subsys = {
2062 	.su_group = {
2063 		.cg_item = {
2064 			.ci_namebuf = "usb_gadget",
2065 			.ci_type = &gadgets_type,
2066 		},
2067 	},
2068 	.su_mutex = __MUTEX_INITIALIZER(gadget_subsys.su_mutex),
2069 };
2070 
2071 void unregister_gadget_item(struct config_item *item)
2072 {
2073 	struct gadget_info *gi = to_gadget_info(item);
2074 
2075 	mutex_lock(&gi->lock);
2076 	unregister_gadget(gi);
2077 	mutex_unlock(&gi->lock);
2078 }
2079 EXPORT_SYMBOL_GPL(unregister_gadget_item);
2080 
2081 static int __init gadget_cfs_init(void)
2082 {
2083 	int ret;
2084 
2085 	config_group_init(&gadget_subsys.su_group);
2086 
2087 	ret = configfs_register_subsystem(&gadget_subsys);
2088 	return ret;
2089 }
2090 module_init(gadget_cfs_init);
2091 
2092 static void __exit gadget_cfs_exit(void)
2093 {
2094 	configfs_unregister_subsystem(&gadget_subsys);
2095 }
2096 module_exit(gadget_cfs_exit);
2097