Merge tag 'renesas-fixes-for-v4.13' of https://git.kernel.org/pub/scm/linux/kernel...
[platform/kernel/linux-exynos.git] / drivers / usb / gadget / configfs.c
1 #include <linux/configfs.h>
2 #include <linux/module.h>
3 #include <linux/slab.h>
4 #include <linux/device.h>
5 #include <linux/nls.h>
6 #include <linux/usb/composite.h>
7 #include <linux/usb/gadget_configfs.h>
8 #include "configfs.h"
9 #include "u_f.h"
10 #include "u_os_desc.h"
11
12 int check_user_usb_string(const char *name,
13                 struct usb_gadget_strings *stringtab_dev)
14 {
15         unsigned primary_lang;
16         unsigned sub_lang;
17         u16 num;
18         int ret;
19
20         ret = kstrtou16(name, 0, &num);
21         if (ret)
22                 return ret;
23
24         primary_lang = num & 0x3ff;
25         sub_lang = num >> 10;
26
27         /* simple sanity check for valid langid */
28         switch (primary_lang) {
29         case 0:
30         case 0x62 ... 0xfe:
31         case 0x100 ... 0x3ff:
32                 return -EINVAL;
33         }
34         if (!sub_lang)
35                 return -EINVAL;
36
37         stringtab_dev->language = num;
38         return 0;
39 }
40
41 #define MAX_NAME_LEN    40
42 #define MAX_USB_STRING_LANGS 2
43
44 static const struct usb_descriptor_header *otg_desc[2];
45
46 struct gadget_info {
47         struct config_group group;
48         struct config_group functions_group;
49         struct config_group configs_group;
50         struct config_group strings_group;
51         struct config_group os_desc_group;
52
53         struct mutex lock;
54         struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
55         struct list_head string_list;
56         struct list_head available_func;
57
58         struct usb_composite_driver composite;
59         struct usb_composite_dev cdev;
60         bool use_os_desc;
61         char b_vendor_code;
62         char qw_sign[OS_STRING_QW_SIGN_LEN];
63 };
64
65 static inline struct gadget_info *to_gadget_info(struct config_item *item)
66 {
67          return container_of(to_config_group(item), struct gadget_info, group);
68 }
69
70 struct config_usb_cfg {
71         struct config_group group;
72         struct config_group strings_group;
73         struct list_head string_list;
74         struct usb_configuration c;
75         struct list_head func_list;
76         struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
77 };
78
79 static inline struct config_usb_cfg *to_config_usb_cfg(struct config_item *item)
80 {
81         return container_of(to_config_group(item), struct config_usb_cfg,
82                         group);
83 }
84
85 struct gadget_strings {
86         struct usb_gadget_strings stringtab_dev;
87         struct usb_string strings[USB_GADGET_FIRST_AVAIL_IDX];
88         char *manufacturer;
89         char *product;
90         char *serialnumber;
91
92         struct config_group group;
93         struct list_head list;
94 };
95
96 struct os_desc {
97         struct config_group group;
98 };
99
100 struct gadget_config_name {
101         struct usb_gadget_strings stringtab_dev;
102         struct usb_string strings;
103         char *configuration;
104
105         struct config_group group;
106         struct list_head list;
107 };
108
109 static int usb_string_copy(const char *s, char **s_copy)
110 {
111         int ret;
112         char *str;
113         char *copy = *s_copy;
114         ret = strlen(s);
115         if (ret > 126)
116                 return -EOVERFLOW;
117
118         str = kstrdup(s, GFP_KERNEL);
119         if (!str)
120                 return -ENOMEM;
121         if (str[ret - 1] == '\n')
122                 str[ret - 1] = '\0';
123         kfree(copy);
124         *s_copy = str;
125         return 0;
126 }
127
128 #define GI_DEVICE_DESC_SIMPLE_R_u8(__name)      \
129 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
130                         char *page)     \
131 {       \
132         return sprintf(page, "0x%02x\n", \
133                 to_gadget_info(item)->cdev.desc.__name); \
134 }
135
136 #define GI_DEVICE_DESC_SIMPLE_R_u16(__name)     \
137 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
138                         char *page)     \
139 {       \
140         return sprintf(page, "0x%04x\n", \
141                 le16_to_cpup(&to_gadget_info(item)->cdev.desc.__name)); \
142 }
143
144
145 #define GI_DEVICE_DESC_SIMPLE_W_u8(_name)               \
146 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
147                 const char *page, size_t len)           \
148 {                                                       \
149         u8 val;                                         \
150         int ret;                                        \
151         ret = kstrtou8(page, 0, &val);                  \
152         if (ret)                                        \
153                 return ret;                             \
154         to_gadget_info(item)->cdev.desc._name = val;    \
155         return len;                                     \
156 }
157
158 #define GI_DEVICE_DESC_SIMPLE_W_u16(_name)      \
159 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
160                 const char *page, size_t len)           \
161 {                                                       \
162         u16 val;                                        \
163         int ret;                                        \
164         ret = kstrtou16(page, 0, &val);                 \
165         if (ret)                                        \
166                 return ret;                             \
167         to_gadget_info(item)->cdev.desc._name = cpu_to_le16p(&val);     \
168         return len;                                     \
169 }
170
171 #define GI_DEVICE_DESC_SIMPLE_RW(_name, _type)  \
172         GI_DEVICE_DESC_SIMPLE_R_##_type(_name)  \
173         GI_DEVICE_DESC_SIMPLE_W_##_type(_name)
174
175 GI_DEVICE_DESC_SIMPLE_R_u16(bcdUSB);
176 GI_DEVICE_DESC_SIMPLE_RW(bDeviceClass, u8);
177 GI_DEVICE_DESC_SIMPLE_RW(bDeviceSubClass, u8);
178 GI_DEVICE_DESC_SIMPLE_RW(bDeviceProtocol, u8);
179 GI_DEVICE_DESC_SIMPLE_RW(bMaxPacketSize0, u8);
180 GI_DEVICE_DESC_SIMPLE_RW(idVendor, u16);
181 GI_DEVICE_DESC_SIMPLE_RW(idProduct, u16);
182 GI_DEVICE_DESC_SIMPLE_R_u16(bcdDevice);
183
184 static ssize_t is_valid_bcd(u16 bcd_val)
185 {
186         if ((bcd_val & 0xf) > 9)
187                 return -EINVAL;
188         if (((bcd_val >> 4) & 0xf) > 9)
189                 return -EINVAL;
190         if (((bcd_val >> 8) & 0xf) > 9)
191                 return -EINVAL;
192         if (((bcd_val >> 12) & 0xf) > 9)
193                 return -EINVAL;
194         return 0;
195 }
196
197 static ssize_t gadget_dev_desc_bcdDevice_store(struct config_item *item,
198                 const char *page, size_t len)
199 {
200         u16 bcdDevice;
201         int ret;
202
203         ret = kstrtou16(page, 0, &bcdDevice);
204         if (ret)
205                 return ret;
206         ret = is_valid_bcd(bcdDevice);
207         if (ret)
208                 return ret;
209
210         to_gadget_info(item)->cdev.desc.bcdDevice = cpu_to_le16(bcdDevice);
211         return len;
212 }
213
214 static ssize_t gadget_dev_desc_bcdUSB_store(struct config_item *item,
215                 const char *page, size_t len)
216 {
217         u16 bcdUSB;
218         int ret;
219
220         ret = kstrtou16(page, 0, &bcdUSB);
221         if (ret)
222                 return ret;
223         ret = is_valid_bcd(bcdUSB);
224         if (ret)
225                 return ret;
226
227         to_gadget_info(item)->cdev.desc.bcdUSB = cpu_to_le16(bcdUSB);
228         return len;
229 }
230
231 static ssize_t gadget_dev_desc_UDC_show(struct config_item *item, char *page)
232 {
233         char *udc_name = to_gadget_info(item)->composite.gadget_driver.udc_name;
234
235         return sprintf(page, "%s\n", udc_name ?: "");
236 }
237
238 static int unregister_gadget(struct gadget_info *gi)
239 {
240         int ret;
241
242         if (!gi->composite.gadget_driver.udc_name)
243                 return -ENODEV;
244
245         ret = usb_gadget_unregister_driver(&gi->composite.gadget_driver);
246         if (ret)
247                 return ret;
248         kfree(gi->composite.gadget_driver.udc_name);
249         gi->composite.gadget_driver.udc_name = NULL;
250         return 0;
251 }
252
253 static ssize_t gadget_dev_desc_UDC_store(struct config_item *item,
254                 const char *page, size_t len)
255 {
256         struct gadget_info *gi = to_gadget_info(item);
257         char *name;
258         int ret;
259
260         name = kstrdup(page, GFP_KERNEL);
261         if (!name)
262                 return -ENOMEM;
263         if (name[len - 1] == '\n')
264                 name[len - 1] = '\0';
265
266         mutex_lock(&gi->lock);
267
268         if (!strlen(name)) {
269                 ret = unregister_gadget(gi);
270                 if (ret)
271                         goto err;
272                 kfree(name);
273         } else {
274                 if (gi->composite.gadget_driver.udc_name) {
275                         ret = -EBUSY;
276                         goto err;
277                 }
278                 gi->composite.gadget_driver.udc_name = name;
279                 ret = usb_gadget_probe_driver(&gi->composite.gadget_driver);
280                 if (ret) {
281                         gi->composite.gadget_driver.udc_name = NULL;
282                         goto err;
283                 }
284         }
285         mutex_unlock(&gi->lock);
286         return len;
287 err:
288         kfree(name);
289         mutex_unlock(&gi->lock);
290         return ret;
291 }
292
293 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceClass);
294 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceSubClass);
295 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceProtocol);
296 CONFIGFS_ATTR(gadget_dev_desc_, bMaxPacketSize0);
297 CONFIGFS_ATTR(gadget_dev_desc_, idVendor);
298 CONFIGFS_ATTR(gadget_dev_desc_, idProduct);
299 CONFIGFS_ATTR(gadget_dev_desc_, bcdDevice);
300 CONFIGFS_ATTR(gadget_dev_desc_, bcdUSB);
301 CONFIGFS_ATTR(gadget_dev_desc_, UDC);
302
303 static struct configfs_attribute *gadget_root_attrs[] = {
304         &gadget_dev_desc_attr_bDeviceClass,
305         &gadget_dev_desc_attr_bDeviceSubClass,
306         &gadget_dev_desc_attr_bDeviceProtocol,
307         &gadget_dev_desc_attr_bMaxPacketSize0,
308         &gadget_dev_desc_attr_idVendor,
309         &gadget_dev_desc_attr_idProduct,
310         &gadget_dev_desc_attr_bcdDevice,
311         &gadget_dev_desc_attr_bcdUSB,
312         &gadget_dev_desc_attr_UDC,
313         NULL,
314 };
315
316 static inline struct gadget_strings *to_gadget_strings(struct config_item *item)
317 {
318          return container_of(to_config_group(item), struct gadget_strings,
319                          group);
320 }
321
322 static inline struct gadget_config_name *to_gadget_config_name(
323                 struct config_item *item)
324 {
325          return container_of(to_config_group(item), struct gadget_config_name,
326                          group);
327 }
328
329 static inline struct usb_function_instance *to_usb_function_instance(
330                 struct config_item *item)
331 {
332          return container_of(to_config_group(item),
333                          struct usb_function_instance, group);
334 }
335
336 static void gadget_info_attr_release(struct config_item *item)
337 {
338         struct gadget_info *gi = to_gadget_info(item);
339
340         WARN_ON(!list_empty(&gi->cdev.configs));
341         WARN_ON(!list_empty(&gi->string_list));
342         WARN_ON(!list_empty(&gi->available_func));
343         kfree(gi->composite.gadget_driver.function);
344         kfree(gi);
345 }
346
347 static struct configfs_item_operations gadget_root_item_ops = {
348         .release                = gadget_info_attr_release,
349 };
350
351 static void gadget_config_attr_release(struct config_item *item)
352 {
353         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
354
355         WARN_ON(!list_empty(&cfg->c.functions));
356         list_del(&cfg->c.list);
357         kfree(cfg->c.label);
358         kfree(cfg);
359 }
360
361 static int config_usb_cfg_link(
362         struct config_item *usb_cfg_ci,
363         struct config_item *usb_func_ci)
364 {
365         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
366         struct usb_composite_dev *cdev = cfg->c.cdev;
367         struct gadget_info *gi = container_of(cdev, struct gadget_info, cdev);
368
369         struct config_group *group = to_config_group(usb_func_ci);
370         struct usb_function_instance *fi = container_of(group,
371                         struct usb_function_instance, group);
372         struct usb_function_instance *a_fi;
373         struct usb_function *f;
374         int ret;
375
376         mutex_lock(&gi->lock);
377         /*
378          * Make sure this function is from within our _this_ gadget and not
379          * from another gadget or a random directory.
380          * Also a function instance can only be linked once.
381          */
382         list_for_each_entry(a_fi, &gi->available_func, cfs_list) {
383                 if (a_fi == fi)
384                         break;
385         }
386         if (a_fi != fi) {
387                 ret = -EINVAL;
388                 goto out;
389         }
390
391         list_for_each_entry(f, &cfg->func_list, list) {
392                 if (f->fi == fi) {
393                         ret = -EEXIST;
394                         goto out;
395                 }
396         }
397
398         f = usb_get_function(fi);
399         if (IS_ERR(f)) {
400                 ret = PTR_ERR(f);
401                 goto out;
402         }
403
404         /* stash the function until we bind it to the gadget */
405         list_add_tail(&f->list, &cfg->func_list);
406         ret = 0;
407 out:
408         mutex_unlock(&gi->lock);
409         return ret;
410 }
411
412 static void config_usb_cfg_unlink(
413         struct config_item *usb_cfg_ci,
414         struct config_item *usb_func_ci)
415 {
416         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
417         struct usb_composite_dev *cdev = cfg->c.cdev;
418         struct gadget_info *gi = container_of(cdev, struct gadget_info, cdev);
419
420         struct config_group *group = to_config_group(usb_func_ci);
421         struct usb_function_instance *fi = container_of(group,
422                         struct usb_function_instance, group);
423         struct usb_function *f;
424
425         /*
426          * ideally I would like to forbid to unlink functions while a gadget is
427          * bound to an UDC. Since this isn't possible at the moment, we simply
428          * force an unbind, the function is available here and then we can
429          * remove the function.
430          */
431         mutex_lock(&gi->lock);
432         if (gi->composite.gadget_driver.udc_name)
433                 unregister_gadget(gi);
434         WARN_ON(gi->composite.gadget_driver.udc_name);
435
436         list_for_each_entry(f, &cfg->func_list, list) {
437                 if (f->fi == fi) {
438                         list_del(&f->list);
439                         usb_put_function(f);
440                         mutex_unlock(&gi->lock);
441                         return;
442                 }
443         }
444         mutex_unlock(&gi->lock);
445         WARN(1, "Unable to locate function to unbind\n");
446 }
447
448 static struct configfs_item_operations gadget_config_item_ops = {
449         .release                = gadget_config_attr_release,
450         .allow_link             = config_usb_cfg_link,
451         .drop_link              = config_usb_cfg_unlink,
452 };
453
454
455 static ssize_t gadget_config_desc_MaxPower_show(struct config_item *item,
456                 char *page)
457 {
458         return sprintf(page, "%u\n", to_config_usb_cfg(item)->c.MaxPower);
459 }
460
461 static ssize_t gadget_config_desc_MaxPower_store(struct config_item *item,
462                 const char *page, size_t len)
463 {
464         u16 val;
465         int ret;
466         ret = kstrtou16(page, 0, &val);
467         if (ret)
468                 return ret;
469         if (DIV_ROUND_UP(val, 8) > 0xff)
470                 return -ERANGE;
471         to_config_usb_cfg(item)->c.MaxPower = val;
472         return len;
473 }
474
475 static ssize_t gadget_config_desc_bmAttributes_show(struct config_item *item,
476                 char *page)
477 {
478         return sprintf(page, "0x%02x\n",
479                 to_config_usb_cfg(item)->c.bmAttributes);
480 }
481
482 static ssize_t gadget_config_desc_bmAttributes_store(struct config_item *item,
483                 const char *page, size_t len)
484 {
485         u8 val;
486         int ret;
487         ret = kstrtou8(page, 0, &val);
488         if (ret)
489                 return ret;
490         if (!(val & USB_CONFIG_ATT_ONE))
491                 return -EINVAL;
492         if (val & ~(USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER |
493                                 USB_CONFIG_ATT_WAKEUP))
494                 return -EINVAL;
495         to_config_usb_cfg(item)->c.bmAttributes = val;
496         return len;
497 }
498
499 CONFIGFS_ATTR(gadget_config_desc_, MaxPower);
500 CONFIGFS_ATTR(gadget_config_desc_, bmAttributes);
501
502 static struct configfs_attribute *gadget_config_attrs[] = {
503         &gadget_config_desc_attr_MaxPower,
504         &gadget_config_desc_attr_bmAttributes,
505         NULL,
506 };
507
508 static struct config_item_type gadget_config_type = {
509         .ct_item_ops    = &gadget_config_item_ops,
510         .ct_attrs       = gadget_config_attrs,
511         .ct_owner       = THIS_MODULE,
512 };
513
514 static struct config_item_type gadget_root_type = {
515         .ct_item_ops    = &gadget_root_item_ops,
516         .ct_attrs       = gadget_root_attrs,
517         .ct_owner       = THIS_MODULE,
518 };
519
520 static void composite_init_dev(struct usb_composite_dev *cdev)
521 {
522         spin_lock_init(&cdev->lock);
523         INIT_LIST_HEAD(&cdev->configs);
524         INIT_LIST_HEAD(&cdev->gstrings);
525 }
526
527 static struct config_group *function_make(
528                 struct config_group *group,
529                 const char *name)
530 {
531         struct gadget_info *gi;
532         struct usb_function_instance *fi;
533         char buf[MAX_NAME_LEN];
534         char *func_name;
535         char *instance_name;
536         int ret;
537
538         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
539         if (ret >= MAX_NAME_LEN)
540                 return ERR_PTR(-ENAMETOOLONG);
541
542         func_name = buf;
543         instance_name = strchr(func_name, '.');
544         if (!instance_name) {
545                 pr_err("Unable to locate . in FUNC.INSTANCE\n");
546                 return ERR_PTR(-EINVAL);
547         }
548         *instance_name = '\0';
549         instance_name++;
550
551         fi = usb_get_function_instance(func_name);
552         if (IS_ERR(fi))
553                 return ERR_CAST(fi);
554
555         ret = config_item_set_name(&fi->group.cg_item, "%s", name);
556         if (ret) {
557                 usb_put_function_instance(fi);
558                 return ERR_PTR(ret);
559         }
560         if (fi->set_inst_name) {
561                 ret = fi->set_inst_name(fi, instance_name);
562                 if (ret) {
563                         usb_put_function_instance(fi);
564                         return ERR_PTR(ret);
565                 }
566         }
567
568         gi = container_of(group, struct gadget_info, functions_group);
569
570         mutex_lock(&gi->lock);
571         list_add_tail(&fi->cfs_list, &gi->available_func);
572         mutex_unlock(&gi->lock);
573         return &fi->group;
574 }
575
576 static void function_drop(
577                 struct config_group *group,
578                 struct config_item *item)
579 {
580         struct usb_function_instance *fi = to_usb_function_instance(item);
581         struct gadget_info *gi;
582
583         gi = container_of(group, struct gadget_info, functions_group);
584
585         mutex_lock(&gi->lock);
586         list_del(&fi->cfs_list);
587         mutex_unlock(&gi->lock);
588         config_item_put(item);
589 }
590
591 static struct configfs_group_operations functions_ops = {
592         .make_group     = &function_make,
593         .drop_item      = &function_drop,
594 };
595
596 static struct config_item_type functions_type = {
597         .ct_group_ops   = &functions_ops,
598         .ct_owner       = THIS_MODULE,
599 };
600
601 GS_STRINGS_RW(gadget_config_name, configuration);
602
603 static struct configfs_attribute *gadget_config_name_langid_attrs[] = {
604         &gadget_config_name_attr_configuration,
605         NULL,
606 };
607
608 static void gadget_config_name_attr_release(struct config_item *item)
609 {
610         struct gadget_config_name *cn = to_gadget_config_name(item);
611
612         kfree(cn->configuration);
613
614         list_del(&cn->list);
615         kfree(cn);
616 }
617
618 USB_CONFIG_STRING_RW_OPS(gadget_config_name);
619 USB_CONFIG_STRINGS_LANG(gadget_config_name, config_usb_cfg);
620
621 static struct config_group *config_desc_make(
622                 struct config_group *group,
623                 const char *name)
624 {
625         struct gadget_info *gi;
626         struct config_usb_cfg *cfg;
627         char buf[MAX_NAME_LEN];
628         char *num_str;
629         u8 num;
630         int ret;
631
632         gi = container_of(group, struct gadget_info, configs_group);
633         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
634         if (ret >= MAX_NAME_LEN)
635                 return ERR_PTR(-ENAMETOOLONG);
636
637         num_str = strchr(buf, '.');
638         if (!num_str) {
639                 pr_err("Unable to locate . in name.bConfigurationValue\n");
640                 return ERR_PTR(-EINVAL);
641         }
642
643         *num_str = '\0';
644         num_str++;
645
646         if (!strlen(buf))
647                 return ERR_PTR(-EINVAL);
648
649         ret = kstrtou8(num_str, 0, &num);
650         if (ret)
651                 return ERR_PTR(ret);
652
653         cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
654         if (!cfg)
655                 return ERR_PTR(-ENOMEM);
656         cfg->c.label = kstrdup(buf, GFP_KERNEL);
657         if (!cfg->c.label) {
658                 ret = -ENOMEM;
659                 goto err;
660         }
661         cfg->c.bConfigurationValue = num;
662         cfg->c.MaxPower = CONFIG_USB_GADGET_VBUS_DRAW;
663         cfg->c.bmAttributes = USB_CONFIG_ATT_ONE;
664         INIT_LIST_HEAD(&cfg->string_list);
665         INIT_LIST_HEAD(&cfg->func_list);
666
667         config_group_init_type_name(&cfg->group, name,
668                                 &gadget_config_type);
669
670         config_group_init_type_name(&cfg->strings_group, "strings",
671                         &gadget_config_name_strings_type);
672         configfs_add_default_group(&cfg->strings_group, &cfg->group);
673
674         ret = usb_add_config_only(&gi->cdev, &cfg->c);
675         if (ret)
676                 goto err;
677
678         return &cfg->group;
679 err:
680         kfree(cfg->c.label);
681         kfree(cfg);
682         return ERR_PTR(ret);
683 }
684
685 static void config_desc_drop(
686                 struct config_group *group,
687                 struct config_item *item)
688 {
689         config_item_put(item);
690 }
691
692 static struct configfs_group_operations config_desc_ops = {
693         .make_group     = &config_desc_make,
694         .drop_item      = &config_desc_drop,
695 };
696
697 static struct config_item_type config_desc_type = {
698         .ct_group_ops   = &config_desc_ops,
699         .ct_owner       = THIS_MODULE,
700 };
701
702 GS_STRINGS_RW(gadget_strings, manufacturer);
703 GS_STRINGS_RW(gadget_strings, product);
704 GS_STRINGS_RW(gadget_strings, serialnumber);
705
706 static struct configfs_attribute *gadget_strings_langid_attrs[] = {
707         &gadget_strings_attr_manufacturer,
708         &gadget_strings_attr_product,
709         &gadget_strings_attr_serialnumber,
710         NULL,
711 };
712
713 static void gadget_strings_attr_release(struct config_item *item)
714 {
715         struct gadget_strings *gs = to_gadget_strings(item);
716
717         kfree(gs->manufacturer);
718         kfree(gs->product);
719         kfree(gs->serialnumber);
720
721         list_del(&gs->list);
722         kfree(gs);
723 }
724
725 USB_CONFIG_STRING_RW_OPS(gadget_strings);
726 USB_CONFIG_STRINGS_LANG(gadget_strings, gadget_info);
727
728 static inline struct os_desc *to_os_desc(struct config_item *item)
729 {
730         return container_of(to_config_group(item), struct os_desc, group);
731 }
732
733 static inline struct gadget_info *os_desc_item_to_gadget_info(
734                 struct config_item *item)
735 {
736         return to_gadget_info(to_os_desc(item)->group.cg_item.ci_parent);
737 }
738
739 static ssize_t os_desc_use_show(struct config_item *item, char *page)
740 {
741         return sprintf(page, "%d\n",
742                         os_desc_item_to_gadget_info(item)->use_os_desc);
743 }
744
745 static ssize_t os_desc_use_store(struct config_item *item, const char *page,
746                                  size_t len)
747 {
748         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
749         int ret;
750         bool use;
751
752         mutex_lock(&gi->lock);
753         ret = strtobool(page, &use);
754         if (!ret) {
755                 gi->use_os_desc = use;
756                 ret = len;
757         }
758         mutex_unlock(&gi->lock);
759
760         return ret;
761 }
762
763 static ssize_t os_desc_b_vendor_code_show(struct config_item *item, char *page)
764 {
765         return sprintf(page, "0x%02x\n",
766                         os_desc_item_to_gadget_info(item)->b_vendor_code);
767 }
768
769 static ssize_t os_desc_b_vendor_code_store(struct config_item *item,
770                                            const char *page, size_t len)
771 {
772         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
773         int ret;
774         u8 b_vendor_code;
775
776         mutex_lock(&gi->lock);
777         ret = kstrtou8(page, 0, &b_vendor_code);
778         if (!ret) {
779                 gi->b_vendor_code = b_vendor_code;
780                 ret = len;
781         }
782         mutex_unlock(&gi->lock);
783
784         return ret;
785 }
786
787 static ssize_t os_desc_qw_sign_show(struct config_item *item, char *page)
788 {
789         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
790         int res;
791
792         res = utf16s_to_utf8s((wchar_t *) gi->qw_sign, OS_STRING_QW_SIGN_LEN,
793                               UTF16_LITTLE_ENDIAN, page, PAGE_SIZE - 1);
794         page[res++] = '\n';
795
796         return res;
797 }
798
799 static ssize_t os_desc_qw_sign_store(struct config_item *item, const char *page,
800                                      size_t len)
801 {
802         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
803         int res, l;
804
805         l = min((int)len, OS_STRING_QW_SIGN_LEN >> 1);
806         if (page[l - 1] == '\n')
807                 --l;
808
809         mutex_lock(&gi->lock);
810         res = utf8s_to_utf16s(page, l,
811                               UTF16_LITTLE_ENDIAN, (wchar_t *) gi->qw_sign,
812                               OS_STRING_QW_SIGN_LEN);
813         if (res > 0)
814                 res = len;
815         mutex_unlock(&gi->lock);
816
817         return res;
818 }
819
820 CONFIGFS_ATTR(os_desc_, use);
821 CONFIGFS_ATTR(os_desc_, b_vendor_code);
822 CONFIGFS_ATTR(os_desc_, qw_sign);
823
824 static struct configfs_attribute *os_desc_attrs[] = {
825         &os_desc_attr_use,
826         &os_desc_attr_b_vendor_code,
827         &os_desc_attr_qw_sign,
828         NULL,
829 };
830
831 static void os_desc_attr_release(struct config_item *item)
832 {
833         struct os_desc *os_desc = to_os_desc(item);
834         kfree(os_desc);
835 }
836
837 static int os_desc_link(struct config_item *os_desc_ci,
838                         struct config_item *usb_cfg_ci)
839 {
840         struct gadget_info *gi = container_of(to_config_group(os_desc_ci),
841                                         struct gadget_info, os_desc_group);
842         struct usb_composite_dev *cdev = &gi->cdev;
843         struct config_usb_cfg *c_target =
844                 container_of(to_config_group(usb_cfg_ci),
845                              struct config_usb_cfg, group);
846         struct usb_configuration *c;
847         int ret;
848
849         mutex_lock(&gi->lock);
850         list_for_each_entry(c, &cdev->configs, list) {
851                 if (c == &c_target->c)
852                         break;
853         }
854         if (c != &c_target->c) {
855                 ret = -EINVAL;
856                 goto out;
857         }
858
859         if (cdev->os_desc_config) {
860                 ret = -EBUSY;
861                 goto out;
862         }
863
864         cdev->os_desc_config = &c_target->c;
865         ret = 0;
866
867 out:
868         mutex_unlock(&gi->lock);
869         return ret;
870 }
871
872 static void os_desc_unlink(struct config_item *os_desc_ci,
873                           struct config_item *usb_cfg_ci)
874 {
875         struct gadget_info *gi = container_of(to_config_group(os_desc_ci),
876                                         struct gadget_info, os_desc_group);
877         struct usb_composite_dev *cdev = &gi->cdev;
878
879         mutex_lock(&gi->lock);
880         if (gi->composite.gadget_driver.udc_name)
881                 unregister_gadget(gi);
882         cdev->os_desc_config = NULL;
883         WARN_ON(gi->composite.gadget_driver.udc_name);
884         mutex_unlock(&gi->lock);
885 }
886
887 static struct configfs_item_operations os_desc_ops = {
888         .release                = os_desc_attr_release,
889         .allow_link             = os_desc_link,
890         .drop_link              = os_desc_unlink,
891 };
892
893 static struct config_item_type os_desc_type = {
894         .ct_item_ops    = &os_desc_ops,
895         .ct_attrs       = os_desc_attrs,
896         .ct_owner       = THIS_MODULE,
897 };
898
899 static inline struct usb_os_desc_ext_prop
900 *to_usb_os_desc_ext_prop(struct config_item *item)
901 {
902         return container_of(item, struct usb_os_desc_ext_prop, item);
903 }
904
905 static ssize_t ext_prop_type_show(struct config_item *item, char *page)
906 {
907         return sprintf(page, "%d\n", to_usb_os_desc_ext_prop(item)->type);
908 }
909
910 static ssize_t ext_prop_type_store(struct config_item *item,
911                                    const char *page, size_t len)
912 {
913         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
914         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
915         u8 type;
916         int ret;
917
918         if (desc->opts_mutex)
919                 mutex_lock(desc->opts_mutex);
920         ret = kstrtou8(page, 0, &type);
921         if (ret)
922                 goto end;
923         if (type < USB_EXT_PROP_UNICODE || type > USB_EXT_PROP_UNICODE_MULTI) {
924                 ret = -EINVAL;
925                 goto end;
926         }
927
928         if ((ext_prop->type == USB_EXT_PROP_BINARY ||
929             ext_prop->type == USB_EXT_PROP_LE32 ||
930             ext_prop->type == USB_EXT_PROP_BE32) &&
931             (type == USB_EXT_PROP_UNICODE ||
932             type == USB_EXT_PROP_UNICODE_ENV ||
933             type == USB_EXT_PROP_UNICODE_LINK))
934                 ext_prop->data_len <<= 1;
935         else if ((ext_prop->type == USB_EXT_PROP_UNICODE ||
936                    ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
937                    ext_prop->type == USB_EXT_PROP_UNICODE_LINK) &&
938                    (type == USB_EXT_PROP_BINARY ||
939                    type == USB_EXT_PROP_LE32 ||
940                    type == USB_EXT_PROP_BE32))
941                 ext_prop->data_len >>= 1;
942         ext_prop->type = type;
943         ret = len;
944
945 end:
946         if (desc->opts_mutex)
947                 mutex_unlock(desc->opts_mutex);
948         return ret;
949 }
950
951 static ssize_t ext_prop_data_show(struct config_item *item, char *page)
952 {
953         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
954         int len = ext_prop->data_len;
955
956         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
957             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
958             ext_prop->type == USB_EXT_PROP_UNICODE_LINK)
959                 len >>= 1;
960         memcpy(page, ext_prop->data, len);
961
962         return len;
963 }
964
965 static ssize_t ext_prop_data_store(struct config_item *item,
966                                    const char *page, size_t len)
967 {
968         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
969         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
970         char *new_data;
971         size_t ret_len = len;
972
973         if (page[len - 1] == '\n' || page[len - 1] == '\0')
974                 --len;
975         new_data = kmemdup(page, len, GFP_KERNEL);
976         if (!new_data)
977                 return -ENOMEM;
978
979         if (desc->opts_mutex)
980                 mutex_lock(desc->opts_mutex);
981         kfree(ext_prop->data);
982         ext_prop->data = new_data;
983         desc->ext_prop_len -= ext_prop->data_len;
984         ext_prop->data_len = len;
985         desc->ext_prop_len += ext_prop->data_len;
986         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
987             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
988             ext_prop->type == USB_EXT_PROP_UNICODE_LINK) {
989                 desc->ext_prop_len -= ext_prop->data_len;
990                 ext_prop->data_len <<= 1;
991                 ext_prop->data_len += 2;
992                 desc->ext_prop_len += ext_prop->data_len;
993         }
994         if (desc->opts_mutex)
995                 mutex_unlock(desc->opts_mutex);
996         return ret_len;
997 }
998
999 CONFIGFS_ATTR(ext_prop_, type);
1000 CONFIGFS_ATTR(ext_prop_, data);
1001
1002 static struct configfs_attribute *ext_prop_attrs[] = {
1003         &ext_prop_attr_type,
1004         &ext_prop_attr_data,
1005         NULL,
1006 };
1007
1008 static void usb_os_desc_ext_prop_release(struct config_item *item)
1009 {
1010         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1011
1012         kfree(ext_prop); /* frees a whole chunk */
1013 }
1014
1015 static struct configfs_item_operations ext_prop_ops = {
1016         .release                = usb_os_desc_ext_prop_release,
1017 };
1018
1019 static struct config_item *ext_prop_make(
1020                 struct config_group *group,
1021                 const char *name)
1022 {
1023         struct usb_os_desc_ext_prop *ext_prop;
1024         struct config_item_type *ext_prop_type;
1025         struct usb_os_desc *desc;
1026         char *vlabuf;
1027
1028         vla_group(data_chunk);
1029         vla_item(data_chunk, struct usb_os_desc_ext_prop, ext_prop, 1);
1030         vla_item(data_chunk, struct config_item_type, ext_prop_type, 1);
1031
1032         vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1033         if (!vlabuf)
1034                 return ERR_PTR(-ENOMEM);
1035
1036         ext_prop = vla_ptr(vlabuf, data_chunk, ext_prop);
1037         ext_prop_type = vla_ptr(vlabuf, data_chunk, ext_prop_type);
1038
1039         desc = container_of(group, struct usb_os_desc, group);
1040         ext_prop_type->ct_item_ops = &ext_prop_ops;
1041         ext_prop_type->ct_attrs = ext_prop_attrs;
1042         ext_prop_type->ct_owner = desc->owner;
1043
1044         config_item_init_type_name(&ext_prop->item, name, ext_prop_type);
1045
1046         ext_prop->name = kstrdup(name, GFP_KERNEL);
1047         if (!ext_prop->name) {
1048                 kfree(vlabuf);
1049                 return ERR_PTR(-ENOMEM);
1050         }
1051         desc->ext_prop_len += 14;
1052         ext_prop->name_len = 2 * strlen(ext_prop->name) + 2;
1053         if (desc->opts_mutex)
1054                 mutex_lock(desc->opts_mutex);
1055         desc->ext_prop_len += ext_prop->name_len;
1056         list_add_tail(&ext_prop->entry, &desc->ext_prop);
1057         ++desc->ext_prop_count;
1058         if (desc->opts_mutex)
1059                 mutex_unlock(desc->opts_mutex);
1060
1061         return &ext_prop->item;
1062 }
1063
1064 static void ext_prop_drop(struct config_group *group, struct config_item *item)
1065 {
1066         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1067         struct usb_os_desc *desc = to_usb_os_desc(&group->cg_item);
1068
1069         if (desc->opts_mutex)
1070                 mutex_lock(desc->opts_mutex);
1071         list_del(&ext_prop->entry);
1072         --desc->ext_prop_count;
1073         kfree(ext_prop->name);
1074         desc->ext_prop_len -= (ext_prop->name_len + ext_prop->data_len + 14);
1075         if (desc->opts_mutex)
1076                 mutex_unlock(desc->opts_mutex);
1077         config_item_put(item);
1078 }
1079
1080 static struct configfs_group_operations interf_grp_ops = {
1081         .make_item      = &ext_prop_make,
1082         .drop_item      = &ext_prop_drop,
1083 };
1084
1085 static ssize_t interf_grp_compatible_id_show(struct config_item *item,
1086                                              char *page)
1087 {
1088         memcpy(page, to_usb_os_desc(item)->ext_compat_id, 8);
1089         return 8;
1090 }
1091
1092 static ssize_t interf_grp_compatible_id_store(struct config_item *item,
1093                                               const char *page, size_t len)
1094 {
1095         struct usb_os_desc *desc = to_usb_os_desc(item);
1096         int l;
1097
1098         l = min_t(int, 8, len);
1099         if (page[l - 1] == '\n')
1100                 --l;
1101         if (desc->opts_mutex)
1102                 mutex_lock(desc->opts_mutex);
1103         memcpy(desc->ext_compat_id, page, l);
1104
1105         if (desc->opts_mutex)
1106                 mutex_unlock(desc->opts_mutex);
1107
1108         return len;
1109 }
1110
1111 static ssize_t interf_grp_sub_compatible_id_show(struct config_item *item,
1112                                                  char *page)
1113 {
1114         memcpy(page, to_usb_os_desc(item)->ext_compat_id + 8, 8);
1115         return 8;
1116 }
1117
1118 static ssize_t interf_grp_sub_compatible_id_store(struct config_item *item,
1119                                                   const char *page, size_t len)
1120 {
1121         struct usb_os_desc *desc = to_usb_os_desc(item);
1122         int l;
1123
1124         l = min_t(int, 8, len);
1125         if (page[l - 1] == '\n')
1126                 --l;
1127         if (desc->opts_mutex)
1128                 mutex_lock(desc->opts_mutex);
1129         memcpy(desc->ext_compat_id + 8, page, l);
1130
1131         if (desc->opts_mutex)
1132                 mutex_unlock(desc->opts_mutex);
1133
1134         return len;
1135 }
1136
1137 CONFIGFS_ATTR(interf_grp_, compatible_id);
1138 CONFIGFS_ATTR(interf_grp_, sub_compatible_id);
1139
1140 static struct configfs_attribute *interf_grp_attrs[] = {
1141         &interf_grp_attr_compatible_id,
1142         &interf_grp_attr_sub_compatible_id,
1143         NULL
1144 };
1145
1146 int usb_os_desc_prepare_interf_dir(struct config_group *parent,
1147                                    int n_interf,
1148                                    struct usb_os_desc **desc,
1149                                    char **names,
1150                                    struct module *owner)
1151 {
1152         struct config_group *os_desc_group;
1153         struct config_item_type *os_desc_type, *interface_type;
1154
1155         vla_group(data_chunk);
1156         vla_item(data_chunk, struct config_group, os_desc_group, 1);
1157         vla_item(data_chunk, struct config_item_type, os_desc_type, 1);
1158         vla_item(data_chunk, struct config_item_type, interface_type, 1);
1159
1160         char *vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1161         if (!vlabuf)
1162                 return -ENOMEM;
1163
1164         os_desc_group = vla_ptr(vlabuf, data_chunk, os_desc_group);
1165         os_desc_type = vla_ptr(vlabuf, data_chunk, os_desc_type);
1166         interface_type = vla_ptr(vlabuf, data_chunk, interface_type);
1167
1168         os_desc_type->ct_owner = owner;
1169         config_group_init_type_name(os_desc_group, "os_desc", os_desc_type);
1170         configfs_add_default_group(os_desc_group, parent);
1171
1172         interface_type->ct_group_ops = &interf_grp_ops;
1173         interface_type->ct_attrs = interf_grp_attrs;
1174         interface_type->ct_owner = owner;
1175
1176         while (n_interf--) {
1177                 struct usb_os_desc *d;
1178
1179                 d = desc[n_interf];
1180                 d->owner = owner;
1181                 config_group_init_type_name(&d->group, "", interface_type);
1182                 config_item_set_name(&d->group.cg_item, "interface.%s",
1183                                      names[n_interf]);
1184                 configfs_add_default_group(&d->group, os_desc_group);
1185         }
1186
1187         return 0;
1188 }
1189 EXPORT_SYMBOL(usb_os_desc_prepare_interf_dir);
1190
1191 static int configfs_do_nothing(struct usb_composite_dev *cdev)
1192 {
1193         WARN_ON(1);
1194         return -EINVAL;
1195 }
1196
1197 int composite_dev_prepare(struct usb_composite_driver *composite,
1198                 struct usb_composite_dev *dev);
1199
1200 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
1201                                   struct usb_ep *ep0);
1202
1203 static void purge_configs_funcs(struct gadget_info *gi)
1204 {
1205         struct usb_configuration        *c;
1206
1207         list_for_each_entry(c, &gi->cdev.configs, list) {
1208                 struct usb_function *f, *tmp;
1209                 struct config_usb_cfg *cfg;
1210
1211                 cfg = container_of(c, struct config_usb_cfg, c);
1212
1213                 list_for_each_entry_safe(f, tmp, &c->functions, list) {
1214
1215                         list_move_tail(&f->list, &cfg->func_list);
1216                         if (f->unbind) {
1217                                 dev_dbg(&gi->cdev.gadget->dev,
1218                                          "unbind function '%s'/%p\n",
1219                                          f->name, f);
1220                                 f->unbind(c, f);
1221                         }
1222                 }
1223                 c->next_interface_id = 0;
1224                 memset(c->interface, 0, sizeof(c->interface));
1225                 c->superspeed_plus = 0;
1226                 c->superspeed = 0;
1227                 c->highspeed = 0;
1228                 c->fullspeed = 0;
1229         }
1230 }
1231
1232 static int configfs_composite_bind(struct usb_gadget *gadget,
1233                 struct usb_gadget_driver *gdriver)
1234 {
1235         struct usb_composite_driver     *composite = to_cdriver(gdriver);
1236         struct gadget_info              *gi = container_of(composite,
1237                                                 struct gadget_info, composite);
1238         struct usb_composite_dev        *cdev = &gi->cdev;
1239         struct usb_configuration        *c;
1240         struct usb_string               *s;
1241         unsigned                        i;
1242         int                             ret;
1243
1244         /* the gi->lock is hold by the caller */
1245         cdev->gadget = gadget;
1246         set_gadget_data(gadget, cdev);
1247         ret = composite_dev_prepare(composite, cdev);
1248         if (ret)
1249                 return ret;
1250         /* and now the gadget bind */
1251         ret = -EINVAL;
1252
1253         if (list_empty(&gi->cdev.configs)) {
1254                 pr_err("Need at least one configuration in %s.\n",
1255                                 gi->composite.name);
1256                 goto err_comp_cleanup;
1257         }
1258
1259
1260         list_for_each_entry(c, &gi->cdev.configs, list) {
1261                 struct config_usb_cfg *cfg;
1262
1263                 cfg = container_of(c, struct config_usb_cfg, c);
1264                 if (list_empty(&cfg->func_list)) {
1265                         pr_err("Config %s/%d of %s needs at least one function.\n",
1266                               c->label, c->bConfigurationValue,
1267                               gi->composite.name);
1268                         goto err_comp_cleanup;
1269                 }
1270         }
1271
1272         /* init all strings */
1273         if (!list_empty(&gi->string_list)) {
1274                 struct gadget_strings *gs;
1275
1276                 i = 0;
1277                 list_for_each_entry(gs, &gi->string_list, list) {
1278
1279                         gi->gstrings[i] = &gs->stringtab_dev;
1280                         gs->stringtab_dev.strings = gs->strings;
1281                         gs->strings[USB_GADGET_MANUFACTURER_IDX].s =
1282                                 gs->manufacturer;
1283                         gs->strings[USB_GADGET_PRODUCT_IDX].s = gs->product;
1284                         gs->strings[USB_GADGET_SERIAL_IDX].s = gs->serialnumber;
1285                         i++;
1286                 }
1287                 gi->gstrings[i] = NULL;
1288                 s = usb_gstrings_attach(&gi->cdev, gi->gstrings,
1289                                 USB_GADGET_FIRST_AVAIL_IDX);
1290                 if (IS_ERR(s)) {
1291                         ret = PTR_ERR(s);
1292                         goto err_comp_cleanup;
1293                 }
1294
1295                 gi->cdev.desc.iManufacturer = s[USB_GADGET_MANUFACTURER_IDX].id;
1296                 gi->cdev.desc.iProduct = s[USB_GADGET_PRODUCT_IDX].id;
1297                 gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
1298         }
1299
1300         if (gi->use_os_desc) {
1301                 cdev->use_os_string = true;
1302                 cdev->b_vendor_code = gi->b_vendor_code;
1303                 memcpy(cdev->qw_sign, gi->qw_sign, OS_STRING_QW_SIGN_LEN);
1304         }
1305
1306         if (gadget_is_otg(gadget) && !otg_desc[0]) {
1307                 struct usb_descriptor_header *usb_desc;
1308
1309                 usb_desc = usb_otg_descriptor_alloc(gadget);
1310                 if (!usb_desc) {
1311                         ret = -ENOMEM;
1312                         goto err_comp_cleanup;
1313                 }
1314                 usb_otg_descriptor_init(gadget, usb_desc);
1315                 otg_desc[0] = usb_desc;
1316                 otg_desc[1] = NULL;
1317         }
1318
1319         /* Go through all configs, attach all functions */
1320         list_for_each_entry(c, &gi->cdev.configs, list) {
1321                 struct config_usb_cfg *cfg;
1322                 struct usb_function *f;
1323                 struct usb_function *tmp;
1324                 struct gadget_config_name *cn;
1325
1326                 if (gadget_is_otg(gadget))
1327                         c->descriptors = otg_desc;
1328
1329                 cfg = container_of(c, struct config_usb_cfg, c);
1330                 if (!list_empty(&cfg->string_list)) {
1331                         i = 0;
1332                         list_for_each_entry(cn, &cfg->string_list, list) {
1333                                 cfg->gstrings[i] = &cn->stringtab_dev;
1334                                 cn->stringtab_dev.strings = &cn->strings;
1335                                 cn->strings.s = cn->configuration;
1336                                 i++;
1337                         }
1338                         cfg->gstrings[i] = NULL;
1339                         s = usb_gstrings_attach(&gi->cdev, cfg->gstrings, 1);
1340                         if (IS_ERR(s)) {
1341                                 ret = PTR_ERR(s);
1342                                 goto err_comp_cleanup;
1343                         }
1344                         c->iConfiguration = s[0].id;
1345                 }
1346
1347                 list_for_each_entry_safe(f, tmp, &cfg->func_list, list) {
1348                         list_del(&f->list);
1349                         ret = usb_add_function(c, f);
1350                         if (ret) {
1351                                 list_add(&f->list, &cfg->func_list);
1352                                 goto err_purge_funcs;
1353                         }
1354                 }
1355                 usb_ep_autoconfig_reset(cdev->gadget);
1356         }
1357         if (cdev->use_os_string) {
1358                 ret = composite_os_desc_req_prepare(cdev, gadget->ep0);
1359                 if (ret)
1360                         goto err_purge_funcs;
1361         }
1362
1363         usb_ep_autoconfig_reset(cdev->gadget);
1364         return 0;
1365
1366 err_purge_funcs:
1367         purge_configs_funcs(gi);
1368 err_comp_cleanup:
1369         composite_dev_cleanup(cdev);
1370         return ret;
1371 }
1372
1373 static void configfs_composite_unbind(struct usb_gadget *gadget)
1374 {
1375         struct usb_composite_dev        *cdev;
1376         struct gadget_info              *gi;
1377
1378         /* the gi->lock is hold by the caller */
1379
1380         cdev = get_gadget_data(gadget);
1381         gi = container_of(cdev, struct gadget_info, cdev);
1382
1383         kfree(otg_desc[0]);
1384         otg_desc[0] = NULL;
1385         purge_configs_funcs(gi);
1386         composite_dev_cleanup(cdev);
1387         usb_ep_autoconfig_reset(cdev->gadget);
1388         cdev->gadget = NULL;
1389         set_gadget_data(gadget, NULL);
1390 }
1391
1392 static const struct usb_gadget_driver configfs_driver_template = {
1393         .bind           = configfs_composite_bind,
1394         .unbind         = configfs_composite_unbind,
1395
1396         .setup          = composite_setup,
1397         .reset          = composite_disconnect,
1398         .disconnect     = composite_disconnect,
1399
1400         .suspend        = composite_suspend,
1401         .resume         = composite_resume,
1402
1403         .max_speed      = USB_SPEED_SUPER,
1404         .driver = {
1405                 .owner          = THIS_MODULE,
1406                 .name           = "configfs-gadget",
1407         },
1408         .match_existing_only = 1,
1409 };
1410
1411 static struct config_group *gadgets_make(
1412                 struct config_group *group,
1413                 const char *name)
1414 {
1415         struct gadget_info *gi;
1416
1417         gi = kzalloc(sizeof(*gi), GFP_KERNEL);
1418         if (!gi)
1419                 return ERR_PTR(-ENOMEM);
1420
1421         config_group_init_type_name(&gi->group, name, &gadget_root_type);
1422
1423         config_group_init_type_name(&gi->functions_group, "functions",
1424                         &functions_type);
1425         configfs_add_default_group(&gi->functions_group, &gi->group);
1426
1427         config_group_init_type_name(&gi->configs_group, "configs",
1428                         &config_desc_type);
1429         configfs_add_default_group(&gi->configs_group, &gi->group);
1430
1431         config_group_init_type_name(&gi->strings_group, "strings",
1432                         &gadget_strings_strings_type);
1433         configfs_add_default_group(&gi->strings_group, &gi->group);
1434
1435         config_group_init_type_name(&gi->os_desc_group, "os_desc",
1436                         &os_desc_type);
1437         configfs_add_default_group(&gi->os_desc_group, &gi->group);
1438
1439         gi->composite.bind = configfs_do_nothing;
1440         gi->composite.unbind = configfs_do_nothing;
1441         gi->composite.suspend = NULL;
1442         gi->composite.resume = NULL;
1443         gi->composite.max_speed = USB_SPEED_SUPER;
1444
1445         mutex_init(&gi->lock);
1446         INIT_LIST_HEAD(&gi->string_list);
1447         INIT_LIST_HEAD(&gi->available_func);
1448
1449         composite_init_dev(&gi->cdev);
1450         gi->cdev.desc.bLength = USB_DT_DEVICE_SIZE;
1451         gi->cdev.desc.bDescriptorType = USB_DT_DEVICE;
1452         gi->cdev.desc.bcdDevice = cpu_to_le16(get_default_bcdDevice());
1453
1454         gi->composite.gadget_driver = configfs_driver_template;
1455
1456         gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
1457         gi->composite.name = gi->composite.gadget_driver.function;
1458
1459         if (!gi->composite.gadget_driver.function)
1460                 goto err;
1461
1462         return &gi->group;
1463 err:
1464         kfree(gi);
1465         return ERR_PTR(-ENOMEM);
1466 }
1467
1468 static void gadgets_drop(struct config_group *group, struct config_item *item)
1469 {
1470         config_item_put(item);
1471 }
1472
1473 static struct configfs_group_operations gadgets_ops = {
1474         .make_group     = &gadgets_make,
1475         .drop_item      = &gadgets_drop,
1476 };
1477
1478 static struct config_item_type gadgets_type = {
1479         .ct_group_ops   = &gadgets_ops,
1480         .ct_owner       = THIS_MODULE,
1481 };
1482
1483 static struct configfs_subsystem gadget_subsys = {
1484         .su_group = {
1485                 .cg_item = {
1486                         .ci_namebuf = "usb_gadget",
1487                         .ci_type = &gadgets_type,
1488                 },
1489         },
1490         .su_mutex = __MUTEX_INITIALIZER(gadget_subsys.su_mutex),
1491 };
1492
1493 void unregister_gadget_item(struct config_item *item)
1494 {
1495         struct gadget_info *gi = to_gadget_info(item);
1496
1497         mutex_lock(&gi->lock);
1498         unregister_gadget(gi);
1499         mutex_unlock(&gi->lock);
1500 }
1501 EXPORT_SYMBOL_GPL(unregister_gadget_item);
1502
1503 static int __init gadget_cfs_init(void)
1504 {
1505         int ret;
1506
1507         config_group_init(&gadget_subsys.su_group);
1508
1509         ret = configfs_register_subsystem(&gadget_subsys);
1510         return ret;
1511 }
1512 module_init(gadget_cfs_init);
1513
1514 static void __exit gadget_cfs_exit(void)
1515 {
1516         configfs_unregister_subsystem(&gadget_subsys);
1517 }
1518 module_exit(gadget_cfs_exit);