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",
 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, "%d",
 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
 791         memcpy(page, gi->qw_sign, OS_STRING_QW_SIGN_LEN);
 792         return OS_STRING_QW_SIGN_LEN;
 793 }
 794
 795 static ssize_t os_desc_qw_sign_store(struct config_item *item, const char *page,
 796                                      size_t len)
 797 {
 798         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 799         int res, l;
 800
 801         l = min((int)len, OS_STRING_QW_SIGN_LEN >> 1);
 802         if (page[l - 1] == '\n')
 803                 --l;
 804
 805         mutex_lock(&gi->lock);
 806         res = utf8s_to_utf16s(page, l,
 807                               UTF16_LITTLE_ENDIAN, (wchar_t *) gi->qw_sign,
 808                               OS_STRING_QW_SIGN_LEN);
 809         if (res > 0)
 810                 res = len;
 811         mutex_unlock(&gi->lock);
 812
 813         return res;
 814 }
 815
 816 CONFIGFS_ATTR(os_desc_, use);
 817 CONFIGFS_ATTR(os_desc_, b_vendor_code);
 818 CONFIGFS_ATTR(os_desc_, qw_sign);
 819
 820 static struct configfs_attribute *os_desc_attrs[] = {
 821         &os_desc_attr_use,
 822         &os_desc_attr_b_vendor_code,
 823         &os_desc_attr_qw_sign,
 824         NULL,
 825 };
 826
 827 static void os_desc_attr_release(struct config_item *item)
 828 {
 829         struct os_desc *os_desc = to_os_desc(item);
 830         kfree(os_desc);
 831 }
 832
 833 static int os_desc_link(struct config_item *os_desc_ci,
 834                         struct config_item *usb_cfg_ci)
 835 {
 836         struct gadget_info *gi = container_of(to_config_group(os_desc_ci),
 837                                         struct gadget_info, os_desc_group);
 838         struct usb_composite_dev *cdev = &gi->cdev;
 839         struct config_usb_cfg *c_target =
 840                 container_of(to_config_group(usb_cfg_ci),
 841                              struct config_usb_cfg, group);
 842         struct usb_configuration *c;
 843         int ret;
 844
 845         mutex_lock(&gi->lock);
 846         list_for_each_entry(c, &cdev->configs, list) {
 847                 if (c == &c_target->c)
 848                         break;
 849         }
 850         if (c != &c_target->c) {
 851                 ret = -EINVAL;
 852                 goto out;
 853         }
 854
 855         if (cdev->os_desc_config) {
 856                 ret = -EBUSY;
 857                 goto out;
 858         }
 859
 860         cdev->os_desc_config = &c_target->c;
 861         ret = 0;
 862
 863 out:
 864         mutex_unlock(&gi->lock);
 865         return ret;
 866 }
 867
 868 static void os_desc_unlink(struct config_item *os_desc_ci,
 869                           struct config_item *usb_cfg_ci)
 870 {
 871         struct gadget_info *gi = container_of(to_config_group(os_desc_ci),
 872                                         struct gadget_info, os_desc_group);
 873         struct usb_composite_dev *cdev = &gi->cdev;
 874
 875         mutex_lock(&gi->lock);
 876         if (gi->composite.gadget_driver.udc_name)
 877                 unregister_gadget(gi);
 878         cdev->os_desc_config = NULL;
 879         WARN_ON(gi->composite.gadget_driver.udc_name);
 880         mutex_unlock(&gi->lock);
 881 }
 882
 883 static struct configfs_item_operations os_desc_ops = {
 884         .release                = os_desc_attr_release,
 885         .allow_link             = os_desc_link,
 886         .drop_link              = os_desc_unlink,
 887 };
 888
 889 static struct config_item_type os_desc_type = {
 890         .ct_item_ops    = &os_desc_ops,
 891         .ct_attrs       = os_desc_attrs,
 892         .ct_owner       = THIS_MODULE,
 893 };
 894
 895 static inline struct usb_os_desc_ext_prop
 896 *to_usb_os_desc_ext_prop(struct config_item *item)
 897 {
 898         return container_of(item, struct usb_os_desc_ext_prop, item);
 899 }
 900
 901 static ssize_t ext_prop_type_show(struct config_item *item, char *page)
 902 {
 903         return sprintf(page, "%d", to_usb_os_desc_ext_prop(item)->type);
 904 }
 905
 906 static ssize_t ext_prop_type_store(struct config_item *item,
 907                                    const char *page, size_t len)
 908 {
 909         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
 910         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
 911         u8 type;
 912         int ret;
 913
 914         if (desc->opts_mutex)
 915                 mutex_lock(desc->opts_mutex);
 916         ret = kstrtou8(page, 0, &type);
 917         if (ret)
 918                 goto end;
 919         if (type < USB_EXT_PROP_UNICODE || type > USB_EXT_PROP_UNICODE_MULTI) {
 920                 ret = -EINVAL;
 921                 goto end;
 922         }
 923
 924         if ((ext_prop->type == USB_EXT_PROP_BINARY ||
 925             ext_prop->type == USB_EXT_PROP_LE32 ||
 926             ext_prop->type == USB_EXT_PROP_BE32) &&
 927             (type == USB_EXT_PROP_UNICODE ||
 928             type == USB_EXT_PROP_UNICODE_ENV ||
 929             type == USB_EXT_PROP_UNICODE_LINK))
 930                 ext_prop->data_len <<= 1;
 931         else if ((ext_prop->type == USB_EXT_PROP_UNICODE ||
 932                    ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
 933                    ext_prop->type == USB_EXT_PROP_UNICODE_LINK) &&
 934                    (type == USB_EXT_PROP_BINARY ||
 935                    type == USB_EXT_PROP_LE32 ||
 936                    type == USB_EXT_PROP_BE32))
 937                 ext_prop->data_len >>= 1;
 938         ext_prop->type = type;
 939         ret = len;
 940
 941 end:
 942         if (desc->opts_mutex)
 943                 mutex_unlock(desc->opts_mutex);
 944         return ret;
 945 }
 946
 947 static ssize_t ext_prop_data_show(struct config_item *item, char *page)
 948 {
 949         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
 950         int len = ext_prop->data_len;
 951
 952         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
 953             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
 954             ext_prop->type == USB_EXT_PROP_UNICODE_LINK)
 955                 len >>= 1;
 956         memcpy(page, ext_prop->data, len);
 957
 958         return len;
 959 }
 960
 961 static ssize_t ext_prop_data_store(struct config_item *item,
 962                                    const char *page, size_t len)
 963 {
 964         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
 965         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
 966         char *new_data;
 967         size_t ret_len = len;
 968
 969         if (page[len - 1] == '\n' || page[len - 1] == '\0')
 970                 --len;
 971         new_data = kmemdup(page, len, GFP_KERNEL);
 972         if (!new_data)
 973                 return -ENOMEM;
 974
 975         if (desc->opts_mutex)
 976                 mutex_lock(desc->opts_mutex);
 977         kfree(ext_prop->data);
 978         ext_prop->data = new_data;
 979         desc->ext_prop_len -= ext_prop->data_len;
 980         ext_prop->data_len = len;
 981         desc->ext_prop_len += ext_prop->data_len;
 982         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
 983             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
 984             ext_prop->type == USB_EXT_PROP_UNICODE_LINK) {
 985                 desc->ext_prop_len -= ext_prop->data_len;
 986                 ext_prop->data_len <<= 1;
 987                 ext_prop->data_len += 2;
 988                 desc->ext_prop_len += ext_prop->data_len;
 989         }
 990         if (desc->opts_mutex)
 991                 mutex_unlock(desc->opts_mutex);
 992         return ret_len;
 993 }
 994
 995 CONFIGFS_ATTR(ext_prop_, type);
 996 CONFIGFS_ATTR(ext_prop_, data);
 997
 998 static struct configfs_attribute *ext_prop_attrs[] = {
 999         &ext_prop_attr_type,
1000         &ext_prop_attr_data,
1001         NULL,
1002 };
1003
1004 static void usb_os_desc_ext_prop_release(struct config_item *item)
1005 {
1006         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1007
1008         kfree(ext_prop); /* frees a whole chunk */
1009 }
1010
1011 static struct configfs_item_operations ext_prop_ops = {
1012         .release                = usb_os_desc_ext_prop_release,
1013 };
1014
1015 static struct config_item *ext_prop_make(
1016                 struct config_group *group,
1017                 const char *name)
1018 {
1019         struct usb_os_desc_ext_prop *ext_prop;
1020         struct config_item_type *ext_prop_type;
1021         struct usb_os_desc *desc;
1022         char *vlabuf;
1023
1024         vla_group(data_chunk);
1025         vla_item(data_chunk, struct usb_os_desc_ext_prop, ext_prop, 1);
1026         vla_item(data_chunk, struct config_item_type, ext_prop_type, 1);
1027
1028         vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1029         if (!vlabuf)
1030                 return ERR_PTR(-ENOMEM);
1031
1032         ext_prop = vla_ptr(vlabuf, data_chunk, ext_prop);
1033         ext_prop_type = vla_ptr(vlabuf, data_chunk, ext_prop_type);
1034
1035         desc = container_of(group, struct usb_os_desc, group);
1036         ext_prop_type->ct_item_ops = &ext_prop_ops;
1037         ext_prop_type->ct_attrs = ext_prop_attrs;
1038         ext_prop_type->ct_owner = desc->owner;
1039
1040         config_item_init_type_name(&ext_prop->item, name, ext_prop_type);
1041
1042         ext_prop->name = kstrdup(name, GFP_KERNEL);
1043         if (!ext_prop->name) {
1044                 kfree(vlabuf);
1045                 return ERR_PTR(-ENOMEM);
1046         }
1047         desc->ext_prop_len += 14;
1048         ext_prop->name_len = 2 * strlen(ext_prop->name) + 2;
1049         if (desc->opts_mutex)
1050                 mutex_lock(desc->opts_mutex);
1051         desc->ext_prop_len += ext_prop->name_len;
1052         list_add_tail(&ext_prop->entry, &desc->ext_prop);
1053         ++desc->ext_prop_count;
1054         if (desc->opts_mutex)
1055                 mutex_unlock(desc->opts_mutex);
1056
1057         return &ext_prop->item;
1058 }
1059
1060 static void ext_prop_drop(struct config_group *group, struct config_item *item)
1061 {
1062         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1063         struct usb_os_desc *desc = to_usb_os_desc(&group->cg_item);
1064
1065         if (desc->opts_mutex)
1066                 mutex_lock(desc->opts_mutex);
1067         list_del(&ext_prop->entry);
1068         --desc->ext_prop_count;
1069         kfree(ext_prop->name);
1070         desc->ext_prop_len -= (ext_prop->name_len + ext_prop->data_len + 14);
1071         if (desc->opts_mutex)
1072                 mutex_unlock(desc->opts_mutex);
1073         config_item_put(item);
1074 }
1075
1076 static struct configfs_group_operations interf_grp_ops = {
1077         .make_item      = &ext_prop_make,
1078         .drop_item      = &ext_prop_drop,
1079 };
1080
1081 static ssize_t interf_grp_compatible_id_show(struct config_item *item,
1082                                              char *page)
1083 {
1084         memcpy(page, to_usb_os_desc(item)->ext_compat_id, 8);
1085         return 8;
1086 }
1087
1088 static ssize_t interf_grp_compatible_id_store(struct config_item *item,
1089                                               const char *page, size_t len)
1090 {
1091         struct usb_os_desc *desc = to_usb_os_desc(item);
1092         int l;
1093
1094         l = min_t(int, 8, len);
1095         if (page[l - 1] == '\n')
1096                 --l;
1097         if (desc->opts_mutex)
1098                 mutex_lock(desc->opts_mutex);
1099         memcpy(desc->ext_compat_id, page, l);
1100
1101         if (desc->opts_mutex)
1102                 mutex_unlock(desc->opts_mutex);
1103
1104         return len;
1105 }
1106
1107 static ssize_t interf_grp_sub_compatible_id_show(struct config_item *item,
1108                                                  char *page)
1109 {
1110         memcpy(page, to_usb_os_desc(item)->ext_compat_id + 8, 8);
1111         return 8;
1112 }
1113
1114 static ssize_t interf_grp_sub_compatible_id_store(struct config_item *item,
1115                                                   const char *page, size_t len)
1116 {
1117         struct usb_os_desc *desc = to_usb_os_desc(item);
1118         int l;
1119
1120         l = min_t(int, 8, len);
1121         if (page[l - 1] == '\n')
1122                 --l;
1123         if (desc->opts_mutex)
1124                 mutex_lock(desc->opts_mutex);
1125         memcpy(desc->ext_compat_id + 8, page, l);
1126
1127         if (desc->opts_mutex)
1128                 mutex_unlock(desc->opts_mutex);
1129
1130         return len;
1131 }
1132
1133 CONFIGFS_ATTR(interf_grp_, compatible_id);
1134 CONFIGFS_ATTR(interf_grp_, sub_compatible_id);
1135
1136 static struct configfs_attribute *interf_grp_attrs[] = {
1137         &interf_grp_attr_compatible_id,
1138         &interf_grp_attr_sub_compatible_id,
1139         NULL
1140 };
1141
1142 int usb_os_desc_prepare_interf_dir(struct config_group *parent,
1143                                    int n_interf,
1144                                    struct usb_os_desc **desc,
1145                                    char **names,
1146                                    struct module *owner)
1147 {
1148         struct config_group *os_desc_group;
1149         struct config_item_type *os_desc_type, *interface_type;
1150
1151         vla_group(data_chunk);
1152         vla_item(data_chunk, struct config_group, os_desc_group, 1);
1153         vla_item(data_chunk, struct config_item_type, os_desc_type, 1);
1154         vla_item(data_chunk, struct config_item_type, interface_type, 1);
1155
1156         char *vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1157         if (!vlabuf)
1158                 return -ENOMEM;
1159
1160         os_desc_group = vla_ptr(vlabuf, data_chunk, os_desc_group);
1161         os_desc_type = vla_ptr(vlabuf, data_chunk, os_desc_type);
1162         interface_type = vla_ptr(vlabuf, data_chunk, interface_type);
1163
1164         os_desc_type->ct_owner = owner;
1165         config_group_init_type_name(os_desc_group, "os_desc", os_desc_type);
1166         configfs_add_default_group(os_desc_group, parent);
1167
1168         interface_type->ct_group_ops = &interf_grp_ops;
1169         interface_type->ct_attrs = interf_grp_attrs;
1170         interface_type->ct_owner = owner;
1171
1172         while (n_interf--) {
1173                 struct usb_os_desc *d;
1174
1175                 d = desc[n_interf];
1176                 d->owner = owner;
1177                 config_group_init_type_name(&d->group, "", interface_type);
1178                 config_item_set_name(&d->group.cg_item, "interface.%s",
1179                                      names[n_interf]);
1180                 configfs_add_default_group(&d->group, os_desc_group);
1181         }
1182
1183         return 0;
1184 }
1185 EXPORT_SYMBOL(usb_os_desc_prepare_interf_dir);
1186
1187 static int configfs_do_nothing(struct usb_composite_dev *cdev)
1188 {
1189         WARN_ON(1);
1190         return -EINVAL;
1191 }
1192
1193 int composite_dev_prepare(struct usb_composite_driver *composite,
1194                 struct usb_composite_dev *dev);
1195
1196 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
1197                                   struct usb_ep *ep0);
1198
1199 static void purge_configs_funcs(struct gadget_info *gi)
1200 {
1201         struct usb_configuration        *c;
1202
1203         list_for_each_entry(c, &gi->cdev.configs, list) {
1204                 struct usb_function *f, *tmp;
1205                 struct config_usb_cfg *cfg;
1206
1207                 cfg = container_of(c, struct config_usb_cfg, c);
1208
1209                 list_for_each_entry_safe(f, tmp, &c->functions, list) {
1210
1211                         list_move_tail(&f->list, &cfg->func_list);
1212                         if (f->unbind) {
1213                                 dev_dbg(&gi->cdev.gadget->dev,
1214                                          "unbind function '%s'/%p\n",
1215                                          f->name, f);
1216                                 f->unbind(c, f);
1217                         }
1218                 }
1219                 c->next_interface_id = 0;
1220                 memset(c->interface, 0, sizeof(c->interface));
1221                 c->superspeed_plus = 0;
1222                 c->superspeed = 0;
1223                 c->highspeed = 0;
1224                 c->fullspeed = 0;
1225         }
1226 }
1227
1228 static int configfs_composite_bind(struct usb_gadget *gadget,
1229                 struct usb_gadget_driver *gdriver)
1230 {
1231         struct usb_composite_driver     *composite = to_cdriver(gdriver);
1232         struct gadget_info              *gi = container_of(composite,
1233                                                 struct gadget_info, composite);
1234         struct usb_composite_dev        *cdev = &gi->cdev;
1235         struct usb_configuration        *c;
1236         struct usb_string               *s;
1237         unsigned                        i;
1238         int                             ret;
1239
1240         /* the gi->lock is hold by the caller */
1241         cdev->gadget = gadget;
1242         set_gadget_data(gadget, cdev);
1243         ret = composite_dev_prepare(composite, cdev);
1244         if (ret)
1245                 return ret;
1246         /* and now the gadget bind */
1247         ret = -EINVAL;
1248
1249         if (list_empty(&gi->cdev.configs)) {
1250                 pr_err("Need at least one configuration in %s.\n",
1251                                 gi->composite.name);
1252                 goto err_comp_cleanup;
1253         }
1254
1255
1256         list_for_each_entry(c, &gi->cdev.configs, list) {
1257                 struct config_usb_cfg *cfg;
1258
1259                 cfg = container_of(c, struct config_usb_cfg, c);
1260                 if (list_empty(&cfg->func_list)) {
1261                         pr_err("Config %s/%d of %s needs at least one function.\n",
1262                               c->label, c->bConfigurationValue,
1263                               gi->composite.name);
1264                         goto err_comp_cleanup;
1265                 }
1266         }
1267
1268         /* init all strings */
1269         if (!list_empty(&gi->string_list)) {
1270                 struct gadget_strings *gs;
1271
1272                 i = 0;
1273                 list_for_each_entry(gs, &gi->string_list, list) {
1274
1275                         gi->gstrings[i] = &gs->stringtab_dev;
1276                         gs->stringtab_dev.strings = gs->strings;
1277                         gs->strings[USB_GADGET_MANUFACTURER_IDX].s =
1278                                 gs->manufacturer;
1279                         gs->strings[USB_GADGET_PRODUCT_IDX].s = gs->product;
1280                         gs->strings[USB_GADGET_SERIAL_IDX].s = gs->serialnumber;
1281                         i++;
1282                 }
1283                 gi->gstrings[i] = NULL;
1284                 s = usb_gstrings_attach(&gi->cdev, gi->gstrings,
1285                                 USB_GADGET_FIRST_AVAIL_IDX);
1286                 if (IS_ERR(s)) {
1287                         ret = PTR_ERR(s);
1288                         goto err_comp_cleanup;
1289                 }
1290
1291                 gi->cdev.desc.iManufacturer = s[USB_GADGET_MANUFACTURER_IDX].id;
1292                 gi->cdev.desc.iProduct = s[USB_GADGET_PRODUCT_IDX].id;
1293                 gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
1294         }
1295
1296         if (gi->use_os_desc) {
1297                 cdev->use_os_string = true;
1298                 cdev->b_vendor_code = gi->b_vendor_code;
1299                 memcpy(cdev->qw_sign, gi->qw_sign, OS_STRING_QW_SIGN_LEN);
1300         }
1301
1302         if (gadget_is_otg(gadget) && !otg_desc[0]) {
1303                 struct usb_descriptor_header *usb_desc;
1304
1305                 usb_desc = usb_otg_descriptor_alloc(gadget);
1306                 if (!usb_desc) {
1307                         ret = -ENOMEM;
1308                         goto err_comp_cleanup;
1309                 }
1310                 usb_otg_descriptor_init(gadget, usb_desc);
1311                 otg_desc[0] = usb_desc;
1312                 otg_desc[1] = NULL;
1313         }
1314
1315         /* Go through all configs, attach all functions */
1316         list_for_each_entry(c, &gi->cdev.configs, list) {
1317                 struct config_usb_cfg *cfg;
1318                 struct usb_function *f;
1319                 struct usb_function *tmp;
1320                 struct gadget_config_name *cn;
1321
1322                 if (gadget_is_otg(gadget))
1323                         c->descriptors = otg_desc;
1324
1325                 cfg = container_of(c, struct config_usb_cfg, c);
1326                 if (!list_empty(&cfg->string_list)) {
1327                         i = 0;
1328                         list_for_each_entry(cn, &cfg->string_list, list) {
1329                                 cfg->gstrings[i] = &cn->stringtab_dev;
1330                                 cn->stringtab_dev.strings = &cn->strings;
1331                                 cn->strings.s = cn->configuration;
1332                                 i++;
1333                         }
1334                         cfg->gstrings[i] = NULL;
1335                         s = usb_gstrings_attach(&gi->cdev, cfg->gstrings, 1);
1336                         if (IS_ERR(s)) {
1337                                 ret = PTR_ERR(s);
1338                                 goto err_comp_cleanup;
1339                         }
1340                         c->iConfiguration = s[0].id;
1341                 }
1342
1343                 list_for_each_entry_safe(f, tmp, &cfg->func_list, list) {
1344                         list_del(&f->list);
1345                         ret = usb_add_function(c, f);
1346                         if (ret) {
1347                                 list_add(&f->list, &cfg->func_list);
1348                                 goto err_purge_funcs;
1349                         }
1350                 }
1351                 usb_ep_autoconfig_reset(cdev->gadget);
1352         }
1353         if (cdev->use_os_string) {
1354                 ret = composite_os_desc_req_prepare(cdev, gadget->ep0);
1355                 if (ret)
1356                         goto err_purge_funcs;
1357         }
1358
1359         usb_ep_autoconfig_reset(cdev->gadget);
1360         return 0;
1361
1362 err_purge_funcs:
1363         purge_configs_funcs(gi);
1364 err_comp_cleanup:
1365         composite_dev_cleanup(cdev);
1366         return ret;
1367 }
1368
1369 static void configfs_composite_unbind(struct usb_gadget *gadget)
1370 {
1371         struct usb_composite_dev        *cdev;
1372         struct gadget_info              *gi;
1373
1374         /* the gi->lock is hold by the caller */
1375
1376         cdev = get_gadget_data(gadget);
1377         gi = container_of(cdev, struct gadget_info, cdev);
1378
1379         kfree(otg_desc[0]);
1380         otg_desc[0] = NULL;
1381         purge_configs_funcs(gi);
1382         composite_dev_cleanup(cdev);
1383         usb_ep_autoconfig_reset(cdev->gadget);
1384         cdev->gadget = NULL;
1385         set_gadget_data(gadget, NULL);
1386 }
1387
1388 static const struct usb_gadget_driver configfs_driver_template = {
1389         .bind           = configfs_composite_bind,
1390         .unbind         = configfs_composite_unbind,
1391
1392         .setup          = composite_setup,
1393         .reset          = composite_disconnect,
1394         .disconnect     = composite_disconnect,
1395
1396         .suspend        = composite_suspend,
1397         .resume         = composite_resume,
1398
1399         .max_speed      = USB_SPEED_SUPER,
1400         .driver = {
1401                 .owner          = THIS_MODULE,
1402                 .name           = "configfs-gadget",
1403         },
1404         .match_existing_only = 1,
1405 };
1406
1407 static struct config_group *gadgets_make(
1408                 struct config_group *group,
1409                 const char *name)
1410 {
1411         struct gadget_info *gi;
1412
1413         gi = kzalloc(sizeof(*gi), GFP_KERNEL);
1414         if (!gi)
1415                 return ERR_PTR(-ENOMEM);
1416
1417         config_group_init_type_name(&gi->group, name, &gadget_root_type);
1418
1419         config_group_init_type_name(&gi->functions_group, "functions",
1420                         &functions_type);
1421         configfs_add_default_group(&gi->functions_group, &gi->group);
1422
1423         config_group_init_type_name(&gi->configs_group, "configs",
1424                         &config_desc_type);
1425         configfs_add_default_group(&gi->configs_group, &gi->group);
1426
1427         config_group_init_type_name(&gi->strings_group, "strings",
1428                         &gadget_strings_strings_type);
1429         configfs_add_default_group(&gi->strings_group, &gi->group);
1430
1431         config_group_init_type_name(&gi->os_desc_group, "os_desc",
1432                         &os_desc_type);
1433         configfs_add_default_group(&gi->os_desc_group, &gi->group);
1434
1435         gi->composite.bind = configfs_do_nothing;
1436         gi->composite.unbind = configfs_do_nothing;
1437         gi->composite.suspend = NULL;
1438         gi->composite.resume = NULL;
1439         gi->composite.max_speed = USB_SPEED_SUPER;
1440
1441         mutex_init(&gi->lock);
1442         INIT_LIST_HEAD(&gi->string_list);
1443         INIT_LIST_HEAD(&gi->available_func);
1444
1445         composite_init_dev(&gi->cdev);
1446         gi->cdev.desc.bLength = USB_DT_DEVICE_SIZE;
1447         gi->cdev.desc.bDescriptorType = USB_DT_DEVICE;
1448         gi->cdev.desc.bcdDevice = cpu_to_le16(get_default_bcdDevice());
1449
1450         gi->composite.gadget_driver = configfs_driver_template;
1451
1452         gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
1453         gi->composite.name = gi->composite.gadget_driver.function;
1454
1455         if (!gi->composite.gadget_driver.function)
1456                 goto err;
1457
1458         return &gi->group;
1459 err:
1460         kfree(gi);
1461         return ERR_PTR(-ENOMEM);
1462 }
1463
1464 static void gadgets_drop(struct config_group *group, struct config_item *item)
1465 {
1466         config_item_put(item);
1467 }
1468
1469 static struct configfs_group_operations gadgets_ops = {
1470         .make_group     = &gadgets_make,
1471         .drop_item      = &gadgets_drop,
1472 };
1473
1474 static struct config_item_type gadgets_type = {
1475         .ct_group_ops   = &gadgets_ops,
1476         .ct_owner       = THIS_MODULE,
1477 };
1478
1479 static struct configfs_subsystem gadget_subsys = {
1480         .su_group = {
1481                 .cg_item = {
1482                         .ci_namebuf = "usb_gadget",
1483                         .ci_type = &gadgets_type,
1484                 },
1485         },
1486         .su_mutex = __MUTEX_INITIALIZER(gadget_subsys.su_mutex),
1487 };
1488
1489 void unregister_gadget_item(struct config_item *item)
1490 {
1491         struct gadget_info *gi = to_gadget_info(item);
1492
1493         mutex_lock(&gi->lock);
1494         unregister_gadget(gi);
1495         mutex_unlock(&gi->lock);
1496 }
1497 EXPORT_SYMBOL_GPL(unregister_gadget_item);
1498
1499 static int __init gadget_cfs_init(void)
1500 {
1501         int ret;
1502
1503         config_group_init(&gadget_subsys.su_group);
1504
1505         ret = configfs_register_subsystem(&gadget_subsys);
1506         return ret;
1507 }
1508 module_init(gadget_cfs_init);
1509
1510 static void __exit gadget_cfs_exit(void)
1511 {
1512         configfs_unregister_subsystem(&gadget_subsys);
1513 }
1514 module_exit(gadget_cfs_exit);