drivers/usb/gadget/configfs.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/configfs.h>
   3 #include <linux/module.h>
   4 #include <linux/slab.h>
   5 #include <linux/device.h>
   6 #include <linux/nls.h>
   7 #include <linux/usb/composite.h>
   8 #include <linux/usb/gadget_configfs.h>
   9 #include "configfs.h"
  10 #include "u_f.h"
  11 #include "u_os_desc.h"
  12
  13 int check_user_usb_string(const char *name,
  14                 struct usb_gadget_strings *stringtab_dev)
  15 {
  16         u16 num;
  17         int ret;
  18
  19         ret = kstrtou16(name, 0, &num);
  20         if (ret)
  21                 return ret;
  22
  23         if (!usb_validate_langid(num))
  24                 return -EINVAL;
  25
  26         stringtab_dev->language = num;
  27         return 0;
  28 }
  29
  30 #define MAX_NAME_LEN    40
  31 #define MAX_USB_STRING_LANGS 2
  32
  33 static const struct usb_descriptor_header *otg_desc[2];
  34
  35 struct gadget_info {
  36         struct config_group group;
  37         struct config_group functions_group;
  38         struct config_group configs_group;
  39         struct config_group strings_group;
  40         struct config_group os_desc_group;
  41
  42         struct mutex lock;
  43         struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
  44         struct list_head string_list;
  45         struct list_head available_func;
  46
  47         struct usb_composite_driver composite;
  48         struct usb_composite_dev cdev;
  49         bool use_os_desc;
  50         char b_vendor_code;
  51         char qw_sign[OS_STRING_QW_SIGN_LEN];
  52         spinlock_t spinlock;
  53         bool unbind;
  54 };
  55
  56 static inline struct gadget_info *to_gadget_info(struct config_item *item)
  57 {
  58          return container_of(to_config_group(item), struct gadget_info, group);
  59 }
  60
  61 struct config_usb_cfg {
  62         struct config_group group;
  63         struct config_group strings_group;
  64         struct list_head string_list;
  65         struct usb_configuration c;
  66         struct list_head func_list;
  67         struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
  68 };
  69
  70 static inline struct config_usb_cfg *to_config_usb_cfg(struct config_item *item)
  71 {
  72         return container_of(to_config_group(item), struct config_usb_cfg,
  73                         group);
  74 }
  75
  76 struct gadget_strings {
  77         struct usb_gadget_strings stringtab_dev;
  78         struct usb_string strings[USB_GADGET_FIRST_AVAIL_IDX];
  79         char *manufacturer;
  80         char *product;
  81         char *serialnumber;
  82
  83         struct config_group group;
  84         struct list_head list;
  85 };
  86
  87 struct os_desc {
  88         struct config_group group;
  89 };
  90
  91 struct gadget_config_name {
  92         struct usb_gadget_strings stringtab_dev;
  93         struct usb_string strings;
  94         char *configuration;
  95
  96         struct config_group group;
  97         struct list_head list;
  98 };
  99
 100 static int usb_string_copy(const char *s, char **s_copy)
 101 {
 102         int ret;
 103         char *str;
 104         char *copy = *s_copy;
 105         ret = strlen(s);
 106         if (ret > 126)
 107                 return -EOVERFLOW;
 108
 109         str = kstrdup(s, GFP_KERNEL);
 110         if (!str)
 111                 return -ENOMEM;
 112         if (str[ret - 1] == '\n')
 113                 str[ret - 1] = '\0';
 114         kfree(copy);
 115         *s_copy = str;
 116         return 0;
 117 }
 118
 119 #define GI_DEVICE_DESC_SIMPLE_R_u8(__name)      \
 120 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
 121                         char *page)     \
 122 {       \
 123         return sprintf(page, "0x%02x\n", \
 124                 to_gadget_info(item)->cdev.desc.__name); \
 125 }
 126
 127 #define GI_DEVICE_DESC_SIMPLE_R_u16(__name)     \
 128 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
 129                         char *page)     \
 130 {       \
 131         return sprintf(page, "0x%04x\n", \
 132                 le16_to_cpup(&to_gadget_info(item)->cdev.desc.__name)); \
 133 }
 134
 135
 136 #define GI_DEVICE_DESC_SIMPLE_W_u8(_name)               \
 137 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
 138                 const char *page, size_t len)           \
 139 {                                                       \
 140         u8 val;                                         \
 141         int ret;                                        \
 142         ret = kstrtou8(page, 0, &val);                  \
 143         if (ret)                                        \
 144                 return ret;                             \
 145         to_gadget_info(item)->cdev.desc._name = val;    \
 146         return len;                                     \
 147 }
 148
 149 #define GI_DEVICE_DESC_SIMPLE_W_u16(_name)      \
 150 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
 151                 const char *page, size_t len)           \
 152 {                                                       \
 153         u16 val;                                        \
 154         int ret;                                        \
 155         ret = kstrtou16(page, 0, &val);                 \
 156         if (ret)                                        \
 157                 return ret;                             \
 158         to_gadget_info(item)->cdev.desc._name = cpu_to_le16p(&val);     \
 159         return len;                                     \
 160 }
 161
 162 #define GI_DEVICE_DESC_SIMPLE_RW(_name, _type)  \
 163         GI_DEVICE_DESC_SIMPLE_R_##_type(_name)  \
 164         GI_DEVICE_DESC_SIMPLE_W_##_type(_name)
 165
 166 GI_DEVICE_DESC_SIMPLE_R_u16(bcdUSB);
 167 GI_DEVICE_DESC_SIMPLE_RW(bDeviceClass, u8);
 168 GI_DEVICE_DESC_SIMPLE_RW(bDeviceSubClass, u8);
 169 GI_DEVICE_DESC_SIMPLE_RW(bDeviceProtocol, u8);
 170 GI_DEVICE_DESC_SIMPLE_RW(bMaxPacketSize0, u8);
 171 GI_DEVICE_DESC_SIMPLE_RW(idVendor, u16);
 172 GI_DEVICE_DESC_SIMPLE_RW(idProduct, u16);
 173 GI_DEVICE_DESC_SIMPLE_R_u16(bcdDevice);
 174
 175 static ssize_t is_valid_bcd(u16 bcd_val)
 176 {
 177         if ((bcd_val & 0xf) > 9)
 178                 return -EINVAL;
 179         if (((bcd_val >> 4) & 0xf) > 9)
 180                 return -EINVAL;
 181         if (((bcd_val >> 8) & 0xf) > 9)
 182                 return -EINVAL;
 183         if (((bcd_val >> 12) & 0xf) > 9)
 184                 return -EINVAL;
 185         return 0;
 186 }
 187
 188 static ssize_t gadget_dev_desc_bcdDevice_store(struct config_item *item,
 189                 const char *page, size_t len)
 190 {
 191         u16 bcdDevice;
 192         int ret;
 193
 194         ret = kstrtou16(page, 0, &bcdDevice);
 195         if (ret)
 196                 return ret;
 197         ret = is_valid_bcd(bcdDevice);
 198         if (ret)
 199                 return ret;
 200
 201         to_gadget_info(item)->cdev.desc.bcdDevice = cpu_to_le16(bcdDevice);
 202         return len;
 203 }
 204
 205 static ssize_t gadget_dev_desc_bcdUSB_store(struct config_item *item,
 206                 const char *page, size_t len)
 207 {
 208         u16 bcdUSB;
 209         int ret;
 210
 211         ret = kstrtou16(page, 0, &bcdUSB);
 212         if (ret)
 213                 return ret;
 214         ret = is_valid_bcd(bcdUSB);
 215         if (ret)
 216                 return ret;
 217
 218         to_gadget_info(item)->cdev.desc.bcdUSB = cpu_to_le16(bcdUSB);
 219         return len;
 220 }
 221
 222 static ssize_t gadget_dev_desc_UDC_show(struct config_item *item, char *page)
 223 {
 224         char *udc_name = to_gadget_info(item)->composite.gadget_driver.udc_name;
 225
 226         return sprintf(page, "%s\n", udc_name ?: "");
 227 }
 228
 229 static int unregister_gadget(struct gadget_info *gi)
 230 {
 231         int ret;
 232
 233         if (!gi->composite.gadget_driver.udc_name)
 234                 return -ENODEV;
 235
 236         ret = usb_gadget_unregister_driver(&gi->composite.gadget_driver);
 237         if (ret)
 238                 return ret;
 239         kfree(gi->composite.gadget_driver.udc_name);
 240         gi->composite.gadget_driver.udc_name = NULL;
 241         return 0;
 242 }
 243
 244 static ssize_t gadget_dev_desc_UDC_store(struct config_item *item,
 245                 const char *page, size_t len)
 246 {
 247         struct gadget_info *gi = to_gadget_info(item);
 248         char *name;
 249         int ret;
 250
 251         if (strlen(page) < len)
 252                 return -EOVERFLOW;
 253
 254         name = kstrdup(page, GFP_KERNEL);
 255         if (!name)
 256                 return -ENOMEM;
 257         if (name[len - 1] == '\n')
 258                 name[len - 1] = '\0';
 259
 260         mutex_lock(&gi->lock);
 261
 262         if (!strlen(name)) {
 263                 ret = unregister_gadget(gi);
 264                 if (ret)
 265                         goto err;
 266                 kfree(name);
 267         } else {
 268                 if (gi->composite.gadget_driver.udc_name) {
 269                         ret = -EBUSY;
 270                         goto err;
 271                 }
 272                 gi->composite.gadget_driver.udc_name = name;
 273                 ret = usb_gadget_probe_driver(&gi->composite.gadget_driver);
 274                 if (ret) {
 275                         gi->composite.gadget_driver.udc_name = NULL;
 276                         goto err;
 277                 }
 278         }
 279         mutex_unlock(&gi->lock);
 280         return len;
 281 err:
 282         kfree(name);
 283         mutex_unlock(&gi->lock);
 284         return ret;
 285 }
 286
 287 static ssize_t gadget_dev_desc_max_speed_show(struct config_item *item,
 288                                               char *page)
 289 {
 290         enum usb_device_speed speed = to_gadget_info(item)->composite.max_speed;
 291
 292         return sprintf(page, "%s\n", usb_speed_string(speed));
 293 }
 294
 295 static ssize_t gadget_dev_desc_max_speed_store(struct config_item *item,
 296                                                const char *page, size_t len)
 297 {
 298         struct gadget_info *gi = to_gadget_info(item);
 299
 300         mutex_lock(&gi->lock);
 301
 302         /* Prevent changing of max_speed after the driver is binded */
 303         if (gi->composite.gadget_driver.udc_name)
 304                 goto err;
 305
 306         if (strncmp(page, "super-speed-plus", 16) == 0)
 307                 gi->composite.max_speed = USB_SPEED_SUPER_PLUS;
 308         else if (strncmp(page, "super-speed", 11) == 0)
 309                 gi->composite.max_speed = USB_SPEED_SUPER;
 310         else if (strncmp(page, "high-speed", 10) == 0)
 311                 gi->composite.max_speed = USB_SPEED_HIGH;
 312         else if (strncmp(page, "full-speed", 10) == 0)
 313                 gi->composite.max_speed = USB_SPEED_FULL;
 314         else if (strncmp(page, "low-speed", 9) == 0)
 315                 gi->composite.max_speed = USB_SPEED_LOW;
 316         else
 317                 goto err;
 318
 319         gi->composite.gadget_driver.max_speed = gi->composite.max_speed;
 320
 321         mutex_unlock(&gi->lock);
 322         return len;
 323 err:
 324         mutex_unlock(&gi->lock);
 325         return -EINVAL;
 326 }
 327
 328 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceClass);
 329 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceSubClass);
 330 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceProtocol);
 331 CONFIGFS_ATTR(gadget_dev_desc_, bMaxPacketSize0);
 332 CONFIGFS_ATTR(gadget_dev_desc_, idVendor);
 333 CONFIGFS_ATTR(gadget_dev_desc_, idProduct);
 334 CONFIGFS_ATTR(gadget_dev_desc_, bcdDevice);
 335 CONFIGFS_ATTR(gadget_dev_desc_, bcdUSB);
 336 CONFIGFS_ATTR(gadget_dev_desc_, UDC);
 337 CONFIGFS_ATTR(gadget_dev_desc_, max_speed);
 338
 339 static struct configfs_attribute *gadget_root_attrs[] = {
 340         &gadget_dev_desc_attr_bDeviceClass,
 341         &gadget_dev_desc_attr_bDeviceSubClass,
 342         &gadget_dev_desc_attr_bDeviceProtocol,
 343         &gadget_dev_desc_attr_bMaxPacketSize0,
 344         &gadget_dev_desc_attr_idVendor,
 345         &gadget_dev_desc_attr_idProduct,
 346         &gadget_dev_desc_attr_bcdDevice,
 347         &gadget_dev_desc_attr_bcdUSB,
 348         &gadget_dev_desc_attr_UDC,
 349         &gadget_dev_desc_attr_max_speed,
 350         NULL,
 351 };
 352
 353 static inline struct gadget_strings *to_gadget_strings(struct config_item *item)
 354 {
 355          return container_of(to_config_group(item), struct gadget_strings,
 356                          group);
 357 }
 358
 359 static inline struct gadget_config_name *to_gadget_config_name(
 360                 struct config_item *item)
 361 {
 362          return container_of(to_config_group(item), struct gadget_config_name,
 363                          group);
 364 }
 365
 366 static inline struct usb_function_instance *to_usb_function_instance(
 367                 struct config_item *item)
 368 {
 369          return container_of(to_config_group(item),
 370                          struct usb_function_instance, group);
 371 }
 372
 373 static void gadget_info_attr_release(struct config_item *item)
 374 {
 375         struct gadget_info *gi = to_gadget_info(item);
 376
 377         WARN_ON(!list_empty(&gi->cdev.configs));
 378         WARN_ON(!list_empty(&gi->string_list));
 379         WARN_ON(!list_empty(&gi->available_func));
 380         kfree(gi->composite.gadget_driver.function);
 381         kfree(gi);
 382 }
 383
 384 static struct configfs_item_operations gadget_root_item_ops = {
 385         .release                = gadget_info_attr_release,
 386 };
 387
 388 static void gadget_config_attr_release(struct config_item *item)
 389 {
 390         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
 391
 392         WARN_ON(!list_empty(&cfg->c.functions));
 393         list_del(&cfg->c.list);
 394         kfree(cfg->c.label);
 395         kfree(cfg);
 396 }
 397
 398 static int config_usb_cfg_link(
 399         struct config_item *usb_cfg_ci,
 400         struct config_item *usb_func_ci)
 401 {
 402         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
 403         struct usb_composite_dev *cdev = cfg->c.cdev;
 404         struct gadget_info *gi = container_of(cdev, struct gadget_info, cdev);
 405
 406         struct config_group *group = to_config_group(usb_func_ci);
 407         struct usb_function_instance *fi = container_of(group,
 408                         struct usb_function_instance, group);
 409         struct usb_function_instance *a_fi;
 410         struct usb_function *f;
 411         int ret;
 412
 413         mutex_lock(&gi->lock);
 414         /*
 415          * Make sure this function is from within our _this_ gadget and not
 416          * from another gadget or a random directory.
 417          * Also a function instance can only be linked once.
 418          */
 419         list_for_each_entry(a_fi, &gi->available_func, cfs_list) {
 420                 if (a_fi == fi)
 421                         break;
 422         }
 423         if (a_fi != fi) {
 424                 ret = -EINVAL;
 425                 goto out;
 426         }
 427
 428         list_for_each_entry(f, &cfg->func_list, list) {
 429                 if (f->fi == fi) {
 430                         ret = -EEXIST;
 431                         goto out;
 432                 }
 433         }
 434
 435         f = usb_get_function(fi);
 436         if (IS_ERR(f)) {
 437                 ret = PTR_ERR(f);
 438                 goto out;
 439         }
 440
 441         /* stash the function until we bind it to the gadget */
 442         list_add_tail(&f->list, &cfg->func_list);
 443         ret = 0;
 444 out:
 445         mutex_unlock(&gi->lock);
 446         return ret;
 447 }
 448
 449 static void config_usb_cfg_unlink(
 450         struct config_item *usb_cfg_ci,
 451         struct config_item *usb_func_ci)
 452 {
 453         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
 454         struct usb_composite_dev *cdev = cfg->c.cdev;
 455         struct gadget_info *gi = container_of(cdev, struct gadget_info, cdev);
 456
 457         struct config_group *group = to_config_group(usb_func_ci);
 458         struct usb_function_instance *fi = container_of(group,
 459                         struct usb_function_instance, group);
 460         struct usb_function *f;
 461
 462         /*
 463          * ideally I would like to forbid to unlink functions while a gadget is
 464          * bound to an UDC. Since this isn't possible at the moment, we simply
 465          * force an unbind, the function is available here and then we can
 466          * remove the function.
 467          */
 468         mutex_lock(&gi->lock);
 469         if (gi->composite.gadget_driver.udc_name)
 470                 unregister_gadget(gi);
 471         WARN_ON(gi->composite.gadget_driver.udc_name);
 472
 473         list_for_each_entry(f, &cfg->func_list, list) {
 474                 if (f->fi == fi) {
 475                         list_del(&f->list);
 476                         usb_put_function(f);
 477                         mutex_unlock(&gi->lock);
 478                         return;
 479                 }
 480         }
 481         mutex_unlock(&gi->lock);
 482         WARN(1, "Unable to locate function to unbind\n");
 483 }
 484
 485 static struct configfs_item_operations gadget_config_item_ops = {
 486         .release                = gadget_config_attr_release,
 487         .allow_link             = config_usb_cfg_link,
 488         .drop_link              = config_usb_cfg_unlink,
 489 };
 490
 491
 492 static ssize_t gadget_config_desc_MaxPower_show(struct config_item *item,
 493                 char *page)
 494 {
 495         return sprintf(page, "%u\n", to_config_usb_cfg(item)->c.MaxPower);
 496 }
 497
 498 static ssize_t gadget_config_desc_MaxPower_store(struct config_item *item,
 499                 const char *page, size_t len)
 500 {
 501         u16 val;
 502         int ret;
 503         ret = kstrtou16(page, 0, &val);
 504         if (ret)
 505                 return ret;
 506         if (DIV_ROUND_UP(val, 8) > 0xff)
 507                 return -ERANGE;
 508         to_config_usb_cfg(item)->c.MaxPower = val;
 509         return len;
 510 }
 511
 512 static ssize_t gadget_config_desc_bmAttributes_show(struct config_item *item,
 513                 char *page)
 514 {
 515         return sprintf(page, "0x%02x\n",
 516                 to_config_usb_cfg(item)->c.bmAttributes);
 517 }
 518
 519 static ssize_t gadget_config_desc_bmAttributes_store(struct config_item *item,
 520                 const char *page, size_t len)
 521 {
 522         u8 val;
 523         int ret;
 524         ret = kstrtou8(page, 0, &val);
 525         if (ret)
 526                 return ret;
 527         if (!(val & USB_CONFIG_ATT_ONE))
 528                 return -EINVAL;
 529         if (val & ~(USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER |
 530                                 USB_CONFIG_ATT_WAKEUP))
 531                 return -EINVAL;
 532         to_config_usb_cfg(item)->c.bmAttributes = val;
 533         return len;
 534 }
 535
 536 CONFIGFS_ATTR(gadget_config_desc_, MaxPower);
 537 CONFIGFS_ATTR(gadget_config_desc_, bmAttributes);
 538
 539 static struct configfs_attribute *gadget_config_attrs[] = {
 540         &gadget_config_desc_attr_MaxPower,
 541         &gadget_config_desc_attr_bmAttributes,
 542         NULL,
 543 };
 544
 545 static const struct config_item_type gadget_config_type = {
 546         .ct_item_ops    = &gadget_config_item_ops,
 547         .ct_attrs       = gadget_config_attrs,
 548         .ct_owner       = THIS_MODULE,
 549 };
 550
 551 static const struct config_item_type gadget_root_type = {
 552         .ct_item_ops    = &gadget_root_item_ops,
 553         .ct_attrs       = gadget_root_attrs,
 554         .ct_owner       = THIS_MODULE,
 555 };
 556
 557 static void composite_init_dev(struct usb_composite_dev *cdev)
 558 {
 559         spin_lock_init(&cdev->lock);
 560         INIT_LIST_HEAD(&cdev->configs);
 561         INIT_LIST_HEAD(&cdev->gstrings);
 562 }
 563
 564 static struct config_group *function_make(
 565                 struct config_group *group,
 566                 const char *name)
 567 {
 568         struct gadget_info *gi;
 569         struct usb_function_instance *fi;
 570         char buf[MAX_NAME_LEN];
 571         char *func_name;
 572         char *instance_name;
 573         int ret;
 574
 575         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
 576         if (ret >= MAX_NAME_LEN)
 577                 return ERR_PTR(-ENAMETOOLONG);
 578
 579         func_name = buf;
 580         instance_name = strchr(func_name, '.');
 581         if (!instance_name) {
 582                 pr_err("Unable to locate . in FUNC.INSTANCE\n");
 583                 return ERR_PTR(-EINVAL);
 584         }
 585         *instance_name = '\0';
 586         instance_name++;
 587
 588         fi = usb_get_function_instance(func_name);
 589         if (IS_ERR(fi))
 590                 return ERR_CAST(fi);
 591
 592         ret = config_item_set_name(&fi->group.cg_item, "%s", name);
 593         if (ret) {
 594                 usb_put_function_instance(fi);
 595                 return ERR_PTR(ret);
 596         }
 597         if (fi->set_inst_name) {
 598                 ret = fi->set_inst_name(fi, instance_name);
 599                 if (ret) {
 600                         usb_put_function_instance(fi);
 601                         return ERR_PTR(ret);
 602                 }
 603         }
 604
 605         gi = container_of(group, struct gadget_info, functions_group);
 606
 607         mutex_lock(&gi->lock);
 608         list_add_tail(&fi->cfs_list, &gi->available_func);
 609         mutex_unlock(&gi->lock);
 610         return &fi->group;
 611 }
 612
 613 static void function_drop(
 614                 struct config_group *group,
 615                 struct config_item *item)
 616 {
 617         struct usb_function_instance *fi = to_usb_function_instance(item);
 618         struct gadget_info *gi;
 619
 620         gi = container_of(group, struct gadget_info, functions_group);
 621
 622         mutex_lock(&gi->lock);
 623         list_del(&fi->cfs_list);
 624         mutex_unlock(&gi->lock);
 625         config_item_put(item);
 626 }
 627
 628 static struct configfs_group_operations functions_ops = {
 629         .make_group     = &function_make,
 630         .drop_item      = &function_drop,
 631 };
 632
 633 static const struct config_item_type functions_type = {
 634         .ct_group_ops   = &functions_ops,
 635         .ct_owner       = THIS_MODULE,
 636 };
 637
 638 GS_STRINGS_RW(gadget_config_name, configuration);
 639
 640 static struct configfs_attribute *gadget_config_name_langid_attrs[] = {
 641         &gadget_config_name_attr_configuration,
 642         NULL,
 643 };
 644
 645 static void gadget_config_name_attr_release(struct config_item *item)
 646 {
 647         struct gadget_config_name *cn = to_gadget_config_name(item);
 648
 649         kfree(cn->configuration);
 650
 651         list_del(&cn->list);
 652         kfree(cn);
 653 }
 654
 655 USB_CONFIG_STRING_RW_OPS(gadget_config_name);
 656 USB_CONFIG_STRINGS_LANG(gadget_config_name, config_usb_cfg);
 657
 658 static struct config_group *config_desc_make(
 659                 struct config_group *group,
 660                 const char *name)
 661 {
 662         struct gadget_info *gi;
 663         struct config_usb_cfg *cfg;
 664         char buf[MAX_NAME_LEN];
 665         char *num_str;
 666         u8 num;
 667         int ret;
 668
 669         gi = container_of(group, struct gadget_info, configs_group);
 670         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
 671         if (ret >= MAX_NAME_LEN)
 672                 return ERR_PTR(-ENAMETOOLONG);
 673
 674         num_str = strchr(buf, '.');
 675         if (!num_str) {
 676                 pr_err("Unable to locate . in name.bConfigurationValue\n");
 677                 return ERR_PTR(-EINVAL);
 678         }
 679
 680         *num_str = '\0';
 681         num_str++;
 682
 683         if (!strlen(buf))
 684                 return ERR_PTR(-EINVAL);
 685
 686         ret = kstrtou8(num_str, 0, &num);
 687         if (ret)
 688                 return ERR_PTR(ret);
 689
 690         cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
 691         if (!cfg)
 692                 return ERR_PTR(-ENOMEM);
 693         cfg->c.label = kstrdup(buf, GFP_KERNEL);
 694         if (!cfg->c.label) {
 695                 ret = -ENOMEM;
 696                 goto err;
 697         }
 698         cfg->c.bConfigurationValue = num;
 699         cfg->c.MaxPower = CONFIG_USB_GADGET_VBUS_DRAW;
 700         cfg->c.bmAttributes = USB_CONFIG_ATT_ONE;
 701         INIT_LIST_HEAD(&cfg->string_list);
 702         INIT_LIST_HEAD(&cfg->func_list);
 703
 704         config_group_init_type_name(&cfg->group, name,
 705                                 &gadget_config_type);
 706
 707         config_group_init_type_name(&cfg->strings_group, "strings",
 708                         &gadget_config_name_strings_type);
 709         configfs_add_default_group(&cfg->strings_group, &cfg->group);
 710
 711         ret = usb_add_config_only(&gi->cdev, &cfg->c);
 712         if (ret)
 713                 goto err;
 714
 715         return &cfg->group;
 716 err:
 717         kfree(cfg->c.label);
 718         kfree(cfg);
 719         return ERR_PTR(ret);
 720 }
 721
 722 static void config_desc_drop(
 723                 struct config_group *group,
 724                 struct config_item *item)
 725 {
 726         config_item_put(item);
 727 }
 728
 729 static struct configfs_group_operations config_desc_ops = {
 730         .make_group     = &config_desc_make,
 731         .drop_item      = &config_desc_drop,
 732 };
 733
 734 static const struct config_item_type config_desc_type = {
 735         .ct_group_ops   = &config_desc_ops,
 736         .ct_owner       = THIS_MODULE,
 737 };
 738
 739 GS_STRINGS_RW(gadget_strings, manufacturer);
 740 GS_STRINGS_RW(gadget_strings, product);
 741 GS_STRINGS_RW(gadget_strings, serialnumber);
 742
 743 static struct configfs_attribute *gadget_strings_langid_attrs[] = {
 744         &gadget_strings_attr_manufacturer,
 745         &gadget_strings_attr_product,
 746         &gadget_strings_attr_serialnumber,
 747         NULL,
 748 };
 749
 750 static void gadget_strings_attr_release(struct config_item *item)
 751 {
 752         struct gadget_strings *gs = to_gadget_strings(item);
 753
 754         kfree(gs->manufacturer);
 755         kfree(gs->product);
 756         kfree(gs->serialnumber);
 757
 758         list_del(&gs->list);
 759         kfree(gs);
 760 }
 761
 762 USB_CONFIG_STRING_RW_OPS(gadget_strings);
 763 USB_CONFIG_STRINGS_LANG(gadget_strings, gadget_info);
 764
 765 static inline struct os_desc *to_os_desc(struct config_item *item)
 766 {
 767         return container_of(to_config_group(item), struct os_desc, group);
 768 }
 769
 770 static inline struct gadget_info *os_desc_item_to_gadget_info(
 771                 struct config_item *item)
 772 {
 773         return to_gadget_info(to_os_desc(item)->group.cg_item.ci_parent);
 774 }
 775
 776 static ssize_t os_desc_use_show(struct config_item *item, char *page)
 777 {
 778         return sprintf(page, "%d\n",
 779                         os_desc_item_to_gadget_info(item)->use_os_desc);
 780 }
 781
 782 static ssize_t os_desc_use_store(struct config_item *item, const char *page,
 783                                  size_t len)
 784 {
 785         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 786         int ret;
 787         bool use;
 788
 789         mutex_lock(&gi->lock);
 790         ret = strtobool(page, &use);
 791         if (!ret) {
 792                 gi->use_os_desc = use;
 793                 ret = len;
 794         }
 795         mutex_unlock(&gi->lock);
 796
 797         return ret;
 798 }
 799
 800 static ssize_t os_desc_b_vendor_code_show(struct config_item *item, char *page)
 801 {
 802         return sprintf(page, "0x%02x\n",
 803                         os_desc_item_to_gadget_info(item)->b_vendor_code);
 804 }
 805
 806 static ssize_t os_desc_b_vendor_code_store(struct config_item *item,
 807                                            const char *page, size_t len)
 808 {
 809         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 810         int ret;
 811         u8 b_vendor_code;
 812
 813         mutex_lock(&gi->lock);
 814         ret = kstrtou8(page, 0, &b_vendor_code);
 815         if (!ret) {
 816                 gi->b_vendor_code = b_vendor_code;
 817                 ret = len;
 818         }
 819         mutex_unlock(&gi->lock);
 820
 821         return ret;
 822 }
 823
 824 static ssize_t os_desc_qw_sign_show(struct config_item *item, char *page)
 825 {
 826         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 827         int res;
 828
 829         res = utf16s_to_utf8s((wchar_t *) gi->qw_sign, OS_STRING_QW_SIGN_LEN,
 830                               UTF16_LITTLE_ENDIAN, page, PAGE_SIZE - 1);
 831         page[res++] = '\n';
 832
 833         return res;
 834 }
 835
 836 static ssize_t os_desc_qw_sign_store(struct config_item *item, const char *page,
 837                                      size_t len)
 838 {
 839         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 840         int res, l;
 841
 842         l = min((int)len, OS_STRING_QW_SIGN_LEN >> 1);
 843         if (page[l - 1] == '\n')
 844                 --l;
 845
 846         mutex_lock(&gi->lock);
 847         res = utf8s_to_utf16s(page, l,
 848                               UTF16_LITTLE_ENDIAN, (wchar_t *) gi->qw_sign,
 849                               OS_STRING_QW_SIGN_LEN);
 850         if (res > 0)
 851                 res = len;
 852         mutex_unlock(&gi->lock);
 853
 854         return res;
 855 }
 856
 857 CONFIGFS_ATTR(os_desc_, use);
 858 CONFIGFS_ATTR(os_desc_, b_vendor_code);
 859 CONFIGFS_ATTR(os_desc_, qw_sign);
 860
 861 static struct configfs_attribute *os_desc_attrs[] = {
 862         &os_desc_attr_use,
 863         &os_desc_attr_b_vendor_code,
 864         &os_desc_attr_qw_sign,
 865         NULL,
 866 };
 867
 868 static void os_desc_attr_release(struct config_item *item)
 869 {
 870         struct os_desc *os_desc = to_os_desc(item);
 871         kfree(os_desc);
 872 }
 873
 874 static int os_desc_link(struct config_item *os_desc_ci,
 875                         struct config_item *usb_cfg_ci)
 876 {
 877         struct gadget_info *gi = container_of(to_config_group(os_desc_ci),
 878                                         struct gadget_info, os_desc_group);
 879         struct usb_composite_dev *cdev = &gi->cdev;
 880         struct config_usb_cfg *c_target =
 881                 container_of(to_config_group(usb_cfg_ci),
 882                              struct config_usb_cfg, group);
 883         struct usb_configuration *c;
 884         int ret;
 885
 886         mutex_lock(&gi->lock);
 887         list_for_each_entry(c, &cdev->configs, list) {
 888                 if (c == &c_target->c)
 889                         break;
 890         }
 891         if (c != &c_target->c) {
 892                 ret = -EINVAL;
 893                 goto out;
 894         }
 895
 896         if (cdev->os_desc_config) {
 897                 ret = -EBUSY;
 898                 goto out;
 899         }
 900
 901         cdev->os_desc_config = &c_target->c;
 902         ret = 0;
 903
 904 out:
 905         mutex_unlock(&gi->lock);
 906         return ret;
 907 }
 908
 909 static void os_desc_unlink(struct config_item *os_desc_ci,
 910                           struct config_item *usb_cfg_ci)
 911 {
 912         struct gadget_info *gi = container_of(to_config_group(os_desc_ci),
 913                                         struct gadget_info, os_desc_group);
 914         struct usb_composite_dev *cdev = &gi->cdev;
 915
 916         mutex_lock(&gi->lock);
 917         if (gi->composite.gadget_driver.udc_name)
 918                 unregister_gadget(gi);
 919         cdev->os_desc_config = NULL;
 920         WARN_ON(gi->composite.gadget_driver.udc_name);
 921         mutex_unlock(&gi->lock);
 922 }
 923
 924 static struct configfs_item_operations os_desc_ops = {
 925         .release                = os_desc_attr_release,
 926         .allow_link             = os_desc_link,
 927         .drop_link              = os_desc_unlink,
 928 };
 929
 930 static struct config_item_type os_desc_type = {
 931         .ct_item_ops    = &os_desc_ops,
 932         .ct_attrs       = os_desc_attrs,
 933         .ct_owner       = THIS_MODULE,
 934 };
 935
 936 static inline struct usb_os_desc_ext_prop
 937 *to_usb_os_desc_ext_prop(struct config_item *item)
 938 {
 939         return container_of(item, struct usb_os_desc_ext_prop, item);
 940 }
 941
 942 static ssize_t ext_prop_type_show(struct config_item *item, char *page)
 943 {
 944         return sprintf(page, "%d\n", to_usb_os_desc_ext_prop(item)->type);
 945 }
 946
 947 static ssize_t ext_prop_type_store(struct config_item *item,
 948                                    const char *page, size_t len)
 949 {
 950         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
 951         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
 952         u8 type;
 953         int ret;
 954
 955         if (desc->opts_mutex)
 956                 mutex_lock(desc->opts_mutex);
 957         ret = kstrtou8(page, 0, &type);
 958         if (ret)
 959                 goto end;
 960         if (type < USB_EXT_PROP_UNICODE || type > USB_EXT_PROP_UNICODE_MULTI) {
 961                 ret = -EINVAL;
 962                 goto end;
 963         }
 964
 965         if ((ext_prop->type == USB_EXT_PROP_BINARY ||
 966             ext_prop->type == USB_EXT_PROP_LE32 ||
 967             ext_prop->type == USB_EXT_PROP_BE32) &&
 968             (type == USB_EXT_PROP_UNICODE ||
 969             type == USB_EXT_PROP_UNICODE_ENV ||
 970             type == USB_EXT_PROP_UNICODE_LINK))
 971                 ext_prop->data_len <<= 1;
 972         else if ((ext_prop->type == USB_EXT_PROP_UNICODE ||
 973                    ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
 974                    ext_prop->type == USB_EXT_PROP_UNICODE_LINK) &&
 975                    (type == USB_EXT_PROP_BINARY ||
 976                    type == USB_EXT_PROP_LE32 ||
 977                    type == USB_EXT_PROP_BE32))
 978                 ext_prop->data_len >>= 1;
 979         ext_prop->type = type;
 980         ret = len;
 981
 982 end:
 983         if (desc->opts_mutex)
 984                 mutex_unlock(desc->opts_mutex);
 985         return ret;
 986 }
 987
 988 static ssize_t ext_prop_data_show(struct config_item *item, char *page)
 989 {
 990         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
 991         int len = ext_prop->data_len;
 992
 993         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
 994             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
 995             ext_prop->type == USB_EXT_PROP_UNICODE_LINK)
 996                 len >>= 1;
 997         memcpy(page, ext_prop->data, len);
 998
 999         return len;
1000 }
1001
1002 static ssize_t ext_prop_data_store(struct config_item *item,
1003                                    const char *page, size_t len)
1004 {
1005         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1006         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
1007         char *new_data;
1008         size_t ret_len = len;
1009
1010         if (page[len - 1] == '\n' || page[len - 1] == '\0')
1011                 --len;
1012         new_data = kmemdup(page, len, GFP_KERNEL);
1013         if (!new_data)
1014                 return -ENOMEM;
1015
1016         if (desc->opts_mutex)
1017                 mutex_lock(desc->opts_mutex);
1018         kfree(ext_prop->data);
1019         ext_prop->data = new_data;
1020         desc->ext_prop_len -= ext_prop->data_len;
1021         ext_prop->data_len = len;
1022         desc->ext_prop_len += ext_prop->data_len;
1023         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
1024             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
1025             ext_prop->type == USB_EXT_PROP_UNICODE_LINK) {
1026                 desc->ext_prop_len -= ext_prop->data_len;
1027                 ext_prop->data_len <<= 1;
1028                 ext_prop->data_len += 2;
1029                 desc->ext_prop_len += ext_prop->data_len;
1030         }
1031         if (desc->opts_mutex)
1032                 mutex_unlock(desc->opts_mutex);
1033         return ret_len;
1034 }
1035
1036 CONFIGFS_ATTR(ext_prop_, type);
1037 CONFIGFS_ATTR(ext_prop_, data);
1038
1039 static struct configfs_attribute *ext_prop_attrs[] = {
1040         &ext_prop_attr_type,
1041         &ext_prop_attr_data,
1042         NULL,
1043 };
1044
1045 static void usb_os_desc_ext_prop_release(struct config_item *item)
1046 {
1047         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1048
1049         kfree(ext_prop); /* frees a whole chunk */
1050 }
1051
1052 static struct configfs_item_operations ext_prop_ops = {
1053         .release                = usb_os_desc_ext_prop_release,
1054 };
1055
1056 static struct config_item *ext_prop_make(
1057                 struct config_group *group,
1058                 const char *name)
1059 {
1060         struct usb_os_desc_ext_prop *ext_prop;
1061         struct config_item_type *ext_prop_type;
1062         struct usb_os_desc *desc;
1063         char *vlabuf;
1064
1065         vla_group(data_chunk);
1066         vla_item(data_chunk, struct usb_os_desc_ext_prop, ext_prop, 1);
1067         vla_item(data_chunk, struct config_item_type, ext_prop_type, 1);
1068
1069         vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1070         if (!vlabuf)
1071                 return ERR_PTR(-ENOMEM);
1072
1073         ext_prop = vla_ptr(vlabuf, data_chunk, ext_prop);
1074         ext_prop_type = vla_ptr(vlabuf, data_chunk, ext_prop_type);
1075
1076         desc = container_of(group, struct usb_os_desc, group);
1077         ext_prop_type->ct_item_ops = &ext_prop_ops;
1078         ext_prop_type->ct_attrs = ext_prop_attrs;
1079         ext_prop_type->ct_owner = desc->owner;
1080
1081         config_item_init_type_name(&ext_prop->item, name, ext_prop_type);
1082
1083         ext_prop->name = kstrdup(name, GFP_KERNEL);
1084         if (!ext_prop->name) {
1085                 kfree(vlabuf);
1086                 return ERR_PTR(-ENOMEM);
1087         }
1088         desc->ext_prop_len += 14;
1089         ext_prop->name_len = 2 * strlen(ext_prop->name) + 2;
1090         if (desc->opts_mutex)
1091                 mutex_lock(desc->opts_mutex);
1092         desc->ext_prop_len += ext_prop->name_len;
1093         list_add_tail(&ext_prop->entry, &desc->ext_prop);
1094         ++desc->ext_prop_count;
1095         if (desc->opts_mutex)
1096                 mutex_unlock(desc->opts_mutex);
1097
1098         return &ext_prop->item;
1099 }
1100
1101 static void ext_prop_drop(struct config_group *group, struct config_item *item)
1102 {
1103         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1104         struct usb_os_desc *desc = to_usb_os_desc(&group->cg_item);
1105
1106         if (desc->opts_mutex)
1107                 mutex_lock(desc->opts_mutex);
1108         list_del(&ext_prop->entry);
1109         --desc->ext_prop_count;
1110         kfree(ext_prop->name);
1111         desc->ext_prop_len -= (ext_prop->name_len + ext_prop->data_len + 14);
1112         if (desc->opts_mutex)
1113                 mutex_unlock(desc->opts_mutex);
1114         config_item_put(item);
1115 }
1116
1117 static struct configfs_group_operations interf_grp_ops = {
1118         .make_item      = &ext_prop_make,
1119         .drop_item      = &ext_prop_drop,
1120 };
1121
1122 static ssize_t interf_grp_compatible_id_show(struct config_item *item,
1123                                              char *page)
1124 {
1125         memcpy(page, to_usb_os_desc(item)->ext_compat_id, 8);
1126         return 8;
1127 }
1128
1129 static ssize_t interf_grp_compatible_id_store(struct config_item *item,
1130                                               const char *page, size_t len)
1131 {
1132         struct usb_os_desc *desc = to_usb_os_desc(item);
1133         int l;
1134
1135         l = min_t(int, 8, len);
1136         if (page[l - 1] == '\n')
1137                 --l;
1138         if (desc->opts_mutex)
1139                 mutex_lock(desc->opts_mutex);
1140         memcpy(desc->ext_compat_id, page, l);
1141
1142         if (desc->opts_mutex)
1143                 mutex_unlock(desc->opts_mutex);
1144
1145         return len;
1146 }
1147
1148 static ssize_t interf_grp_sub_compatible_id_show(struct config_item *item,
1149                                                  char *page)
1150 {
1151         memcpy(page, to_usb_os_desc(item)->ext_compat_id + 8, 8);
1152         return 8;
1153 }
1154
1155 static ssize_t interf_grp_sub_compatible_id_store(struct config_item *item,
1156                                                   const char *page, size_t len)
1157 {
1158         struct usb_os_desc *desc = to_usb_os_desc(item);
1159         int l;
1160
1161         l = min_t(int, 8, len);
1162         if (page[l - 1] == '\n')
1163                 --l;
1164         if (desc->opts_mutex)
1165                 mutex_lock(desc->opts_mutex);
1166         memcpy(desc->ext_compat_id + 8, page, l);
1167
1168         if (desc->opts_mutex)
1169                 mutex_unlock(desc->opts_mutex);
1170
1171         return len;
1172 }
1173
1174 CONFIGFS_ATTR(interf_grp_, compatible_id);
1175 CONFIGFS_ATTR(interf_grp_, sub_compatible_id);
1176
1177 static struct configfs_attribute *interf_grp_attrs[] = {
1178         &interf_grp_attr_compatible_id,
1179         &interf_grp_attr_sub_compatible_id,
1180         NULL
1181 };
1182
1183 struct config_group *usb_os_desc_prepare_interf_dir(
1184                 struct config_group *parent,
1185                 int n_interf,
1186                 struct usb_os_desc **desc,
1187                 char **names,
1188                 struct module *owner)
1189 {
1190         struct config_group *os_desc_group;
1191         struct config_item_type *os_desc_type, *interface_type;
1192
1193         vla_group(data_chunk);
1194         vla_item(data_chunk, struct config_group, os_desc_group, 1);
1195         vla_item(data_chunk, struct config_item_type, os_desc_type, 1);
1196         vla_item(data_chunk, struct config_item_type, interface_type, 1);
1197
1198         char *vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1199         if (!vlabuf)
1200                 return ERR_PTR(-ENOMEM);
1201
1202         os_desc_group = vla_ptr(vlabuf, data_chunk, os_desc_group);
1203         os_desc_type = vla_ptr(vlabuf, data_chunk, os_desc_type);
1204         interface_type = vla_ptr(vlabuf, data_chunk, interface_type);
1205
1206         os_desc_type->ct_owner = owner;
1207         config_group_init_type_name(os_desc_group, "os_desc", os_desc_type);
1208         configfs_add_default_group(os_desc_group, parent);
1209
1210         interface_type->ct_group_ops = &interf_grp_ops;
1211         interface_type->ct_attrs = interf_grp_attrs;
1212         interface_type->ct_owner = owner;
1213
1214         while (n_interf--) {
1215                 struct usb_os_desc *d;
1216
1217                 d = desc[n_interf];
1218                 d->owner = owner;
1219                 config_group_init_type_name(&d->group, "", interface_type);
1220                 config_item_set_name(&d->group.cg_item, "interface.%s",
1221                                      names[n_interf]);
1222                 configfs_add_default_group(&d->group, os_desc_group);
1223         }
1224
1225         return os_desc_group;
1226 }
1227 EXPORT_SYMBOL(usb_os_desc_prepare_interf_dir);
1228
1229 static int configfs_do_nothing(struct usb_composite_dev *cdev)
1230 {
1231         WARN_ON(1);
1232         return -EINVAL;
1233 }
1234
1235 int composite_dev_prepare(struct usb_composite_driver *composite,
1236                 struct usb_composite_dev *dev);
1237
1238 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
1239                                   struct usb_ep *ep0);
1240
1241 static void purge_configs_funcs(struct gadget_info *gi)
1242 {
1243         struct usb_configuration        *c;
1244
1245         list_for_each_entry(c, &gi->cdev.configs, list) {
1246                 struct usb_function *f, *tmp;
1247                 struct config_usb_cfg *cfg;
1248
1249                 cfg = container_of(c, struct config_usb_cfg, c);
1250
1251                 list_for_each_entry_safe(f, tmp, &c->functions, list) {
1252
1253                         list_move_tail(&f->list, &cfg->func_list);
1254                         if (f->unbind) {
1255                                 dev_dbg(&gi->cdev.gadget->dev,
1256                                         "unbind function '%s'/%p\n",
1257                                         f->name, f);
1258                                 f->unbind(c, f);
1259                         }
1260                 }
1261                 c->next_interface_id = 0;
1262                 memset(c->interface, 0, sizeof(c->interface));
1263                 c->superspeed_plus = 0;
1264                 c->superspeed = 0;
1265                 c->highspeed = 0;
1266                 c->fullspeed = 0;
1267         }
1268 }
1269
1270 static int configfs_composite_bind(struct usb_gadget *gadget,
1271                 struct usb_gadget_driver *gdriver)
1272 {
1273         struct usb_composite_driver     *composite = to_cdriver(gdriver);
1274         struct gadget_info              *gi = container_of(composite,
1275                                                 struct gadget_info, composite);
1276         struct usb_composite_dev        *cdev = &gi->cdev;
1277         struct usb_configuration        *c;
1278         struct usb_string               *s;
1279         unsigned                        i;
1280         int                             ret;
1281
1282         /* the gi->lock is hold by the caller */
1283         gi->unbind = 0;
1284         cdev->gadget = gadget;
1285         set_gadget_data(gadget, cdev);
1286         ret = composite_dev_prepare(composite, cdev);
1287         if (ret)
1288                 return ret;
1289         /* and now the gadget bind */
1290         ret = -EINVAL;
1291
1292         if (list_empty(&gi->cdev.configs)) {
1293                 pr_err("Need at least one configuration in %s.\n",
1294                                 gi->composite.name);
1295                 goto err_comp_cleanup;
1296         }
1297
1298
1299         list_for_each_entry(c, &gi->cdev.configs, list) {
1300                 struct config_usb_cfg *cfg;
1301
1302                 cfg = container_of(c, struct config_usb_cfg, c);
1303                 if (list_empty(&cfg->func_list)) {
1304                         pr_err("Config %s/%d of %s needs at least one function.\n",
1305                               c->label, c->bConfigurationValue,
1306                               gi->composite.name);
1307                         goto err_comp_cleanup;
1308                 }
1309         }
1310
1311         /* init all strings */
1312         if (!list_empty(&gi->string_list)) {
1313                 struct gadget_strings *gs;
1314
1315                 i = 0;
1316                 list_for_each_entry(gs, &gi->string_list, list) {
1317
1318                         gi->gstrings[i] = &gs->stringtab_dev;
1319                         gs->stringtab_dev.strings = gs->strings;
1320                         gs->strings[USB_GADGET_MANUFACTURER_IDX].s =
1321                                 gs->manufacturer;
1322                         gs->strings[USB_GADGET_PRODUCT_IDX].s = gs->product;
1323                         gs->strings[USB_GADGET_SERIAL_IDX].s = gs->serialnumber;
1324                         i++;
1325                 }
1326                 gi->gstrings[i] = NULL;
1327                 s = usb_gstrings_attach(&gi->cdev, gi->gstrings,
1328                                 USB_GADGET_FIRST_AVAIL_IDX);
1329                 if (IS_ERR(s)) {
1330                         ret = PTR_ERR(s);
1331                         goto err_comp_cleanup;
1332                 }
1333
1334                 gi->cdev.desc.iManufacturer = s[USB_GADGET_MANUFACTURER_IDX].id;
1335                 gi->cdev.desc.iProduct = s[USB_GADGET_PRODUCT_IDX].id;
1336                 gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
1337         }
1338
1339         if (gi->use_os_desc) {
1340                 cdev->use_os_string = true;
1341                 cdev->b_vendor_code = gi->b_vendor_code;
1342                 memcpy(cdev->qw_sign, gi->qw_sign, OS_STRING_QW_SIGN_LEN);
1343         }
1344
1345         if (gadget_is_otg(gadget) && !otg_desc[0]) {
1346                 struct usb_descriptor_header *usb_desc;
1347
1348                 usb_desc = usb_otg_descriptor_alloc(gadget);
1349                 if (!usb_desc) {
1350                         ret = -ENOMEM;
1351                         goto err_comp_cleanup;
1352                 }
1353                 usb_otg_descriptor_init(gadget, usb_desc);
1354                 otg_desc[0] = usb_desc;
1355                 otg_desc[1] = NULL;
1356         }
1357
1358         /* Go through all configs, attach all functions */
1359         list_for_each_entry(c, &gi->cdev.configs, list) {
1360                 struct config_usb_cfg *cfg;
1361                 struct usb_function *f;
1362                 struct usb_function *tmp;
1363                 struct gadget_config_name *cn;
1364
1365                 if (gadget_is_otg(gadget))
1366                         c->descriptors = otg_desc;
1367
1368                 cfg = container_of(c, struct config_usb_cfg, c);
1369                 if (!list_empty(&cfg->string_list)) {
1370                         i = 0;
1371                         list_for_each_entry(cn, &cfg->string_list, list) {
1372                                 cfg->gstrings[i] = &cn->stringtab_dev;
1373                                 cn->stringtab_dev.strings = &cn->strings;
1374                                 cn->strings.s = cn->configuration;
1375                                 i++;
1376                         }
1377                         cfg->gstrings[i] = NULL;
1378                         s = usb_gstrings_attach(&gi->cdev, cfg->gstrings, 1);
1379                         if (IS_ERR(s)) {
1380                                 ret = PTR_ERR(s);
1381                                 goto err_comp_cleanup;
1382                         }
1383                         c->iConfiguration = s[0].id;
1384                 }
1385
1386                 list_for_each_entry_safe(f, tmp, &cfg->func_list, list) {
1387                         list_del(&f->list);
1388                         ret = usb_add_function(c, f);
1389                         if (ret) {
1390                                 list_add(&f->list, &cfg->func_list);
1391                                 goto err_purge_funcs;
1392                         }
1393                 }
1394                 usb_ep_autoconfig_reset(cdev->gadget);
1395         }
1396         if (cdev->use_os_string) {
1397                 ret = composite_os_desc_req_prepare(cdev, gadget->ep0);
1398                 if (ret)
1399                         goto err_purge_funcs;
1400         }
1401
1402         usb_ep_autoconfig_reset(cdev->gadget);
1403         return 0;
1404
1405 err_purge_funcs:
1406         purge_configs_funcs(gi);
1407 err_comp_cleanup:
1408         composite_dev_cleanup(cdev);
1409         return ret;
1410 }
1411
1412 static void configfs_composite_unbind(struct usb_gadget *gadget)
1413 {
1414         struct usb_composite_dev        *cdev;
1415         struct gadget_info              *gi;
1416         unsigned long flags;
1417
1418         /* the gi->lock is hold by the caller */
1419
1420         cdev = get_gadget_data(gadget);
1421         gi = container_of(cdev, struct gadget_info, cdev);
1422         spin_lock_irqsave(&gi->spinlock, flags);
1423         gi->unbind = 1;
1424         spin_unlock_irqrestore(&gi->spinlock, flags);
1425
1426         kfree(otg_desc[0]);
1427         otg_desc[0] = NULL;
1428         purge_configs_funcs(gi);
1429         composite_dev_cleanup(cdev);
1430         usb_ep_autoconfig_reset(cdev->gadget);
1431         spin_lock_irqsave(&gi->spinlock, flags);
1432         cdev->gadget = NULL;
1433         set_gadget_data(gadget, NULL);
1434         spin_unlock_irqrestore(&gi->spinlock, flags);
1435 }
1436
1437 static int configfs_composite_setup(struct usb_gadget *gadget,
1438                 const struct usb_ctrlrequest *ctrl)
1439 {
1440         struct usb_composite_dev *cdev;
1441         struct gadget_info *gi;
1442         unsigned long flags;
1443         int ret;
1444
1445         cdev = get_gadget_data(gadget);
1446         if (!cdev)
1447                 return 0;
1448
1449         gi = container_of(cdev, struct gadget_info, cdev);
1450         spin_lock_irqsave(&gi->spinlock, flags);
1451         cdev = get_gadget_data(gadget);
1452         if (!cdev || gi->unbind) {
1453                 spin_unlock_irqrestore(&gi->spinlock, flags);
1454                 return 0;
1455         }
1456
1457         ret = composite_setup(gadget, ctrl);
1458         spin_unlock_irqrestore(&gi->spinlock, flags);
1459         return ret;
1460 }
1461
1462 static void configfs_composite_disconnect(struct usb_gadget *gadget)
1463 {
1464         struct usb_composite_dev *cdev;
1465         struct gadget_info *gi;
1466         unsigned long flags;
1467
1468         cdev = get_gadget_data(gadget);
1469         if (!cdev)
1470                 return;
1471
1472         gi = container_of(cdev, struct gadget_info, cdev);
1473         spin_lock_irqsave(&gi->spinlock, flags);
1474         cdev = get_gadget_data(gadget);
1475         if (!cdev || gi->unbind) {
1476                 spin_unlock_irqrestore(&gi->spinlock, flags);
1477                 return;
1478         }
1479
1480         composite_disconnect(gadget);
1481         spin_unlock_irqrestore(&gi->spinlock, flags);
1482 }
1483
1484 static void configfs_composite_suspend(struct usb_gadget *gadget)
1485 {
1486         struct usb_composite_dev *cdev;
1487         struct gadget_info *gi;
1488         unsigned long flags;
1489
1490         cdev = get_gadget_data(gadget);
1491         if (!cdev)
1492                 return;
1493
1494         gi = container_of(cdev, struct gadget_info, cdev);
1495         spin_lock_irqsave(&gi->spinlock, flags);
1496         cdev = get_gadget_data(gadget);
1497         if (!cdev || gi->unbind) {
1498                 spin_unlock_irqrestore(&gi->spinlock, flags);
1499                 return;
1500         }
1501
1502         composite_suspend(gadget);
1503         spin_unlock_irqrestore(&gi->spinlock, flags);
1504 }
1505
1506 static void configfs_composite_resume(struct usb_gadget *gadget)
1507 {
1508         struct usb_composite_dev *cdev;
1509         struct gadget_info *gi;
1510         unsigned long flags;
1511
1512         cdev = get_gadget_data(gadget);
1513         if (!cdev)
1514                 return;
1515
1516         gi = container_of(cdev, struct gadget_info, cdev);
1517         spin_lock_irqsave(&gi->spinlock, flags);
1518         cdev = get_gadget_data(gadget);
1519         if (!cdev || gi->unbind) {
1520                 spin_unlock_irqrestore(&gi->spinlock, flags);
1521                 return;
1522         }
1523
1524         composite_resume(gadget);
1525         spin_unlock_irqrestore(&gi->spinlock, flags);
1526 }
1527
1528 static const struct usb_gadget_driver configfs_driver_template = {
1529         .bind           = configfs_composite_bind,
1530         .unbind         = configfs_composite_unbind,
1531
1532         .setup          = configfs_composite_setup,
1533         .reset          = configfs_composite_disconnect,
1534         .disconnect     = configfs_composite_disconnect,
1535
1536         .suspend        = configfs_composite_suspend,
1537         .resume         = configfs_composite_resume,
1538
1539         .max_speed      = USB_SPEED_SUPER,
1540         .driver = {
1541                 .owner          = THIS_MODULE,
1542                 .name           = "configfs-gadget",
1543         },
1544         .match_existing_only = 1,
1545 };
1546
1547 static struct config_group *gadgets_make(
1548                 struct config_group *group,
1549                 const char *name)
1550 {
1551         struct gadget_info *gi;
1552
1553         gi = kzalloc(sizeof(*gi), GFP_KERNEL);
1554         if (!gi)
1555                 return ERR_PTR(-ENOMEM);
1556
1557         config_group_init_type_name(&gi->group, name, &gadget_root_type);
1558
1559         config_group_init_type_name(&gi->functions_group, "functions",
1560                         &functions_type);
1561         configfs_add_default_group(&gi->functions_group, &gi->group);
1562
1563         config_group_init_type_name(&gi->configs_group, "configs",
1564                         &config_desc_type);
1565         configfs_add_default_group(&gi->configs_group, &gi->group);
1566
1567         config_group_init_type_name(&gi->strings_group, "strings",
1568                         &gadget_strings_strings_type);
1569         configfs_add_default_group(&gi->strings_group, &gi->group);
1570
1571         config_group_init_type_name(&gi->os_desc_group, "os_desc",
1572                         &os_desc_type);
1573         configfs_add_default_group(&gi->os_desc_group, &gi->group);
1574
1575         gi->composite.bind = configfs_do_nothing;
1576         gi->composite.unbind = configfs_do_nothing;
1577         gi->composite.suspend = NULL;
1578         gi->composite.resume = NULL;
1579         gi->composite.max_speed = USB_SPEED_SUPER;
1580
1581         spin_lock_init(&gi->spinlock);
1582         mutex_init(&gi->lock);
1583         INIT_LIST_HEAD(&gi->string_list);
1584         INIT_LIST_HEAD(&gi->available_func);
1585
1586         composite_init_dev(&gi->cdev);
1587         gi->cdev.desc.bLength = USB_DT_DEVICE_SIZE;
1588         gi->cdev.desc.bDescriptorType = USB_DT_DEVICE;
1589         gi->cdev.desc.bcdDevice = cpu_to_le16(get_default_bcdDevice());
1590
1591         gi->composite.gadget_driver = configfs_driver_template;
1592
1593         gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
1594         gi->composite.name = gi->composite.gadget_driver.function;
1595
1596         if (!gi->composite.gadget_driver.function)
1597                 goto err;
1598
1599         return &gi->group;
1600 err:
1601         kfree(gi);
1602         return ERR_PTR(-ENOMEM);
1603 }
1604
1605 static void gadgets_drop(struct config_group *group, struct config_item *item)
1606 {
1607         config_item_put(item);
1608 }
1609
1610 static struct configfs_group_operations gadgets_ops = {
1611         .make_group     = &gadgets_make,
1612         .drop_item      = &gadgets_drop,
1613 };
1614
1615 static const struct config_item_type gadgets_type = {
1616         .ct_group_ops   = &gadgets_ops,
1617         .ct_owner       = THIS_MODULE,
1618 };
1619
1620 static struct configfs_subsystem gadget_subsys = {
1621         .su_group = {
1622                 .cg_item = {
1623                         .ci_namebuf = "usb_gadget",
1624                         .ci_type = &gadgets_type,
1625                 },
1626         },
1627         .su_mutex = __MUTEX_INITIALIZER(gadget_subsys.su_mutex),
1628 };
1629
1630 void unregister_gadget_item(struct config_item *item)
1631 {
1632         struct gadget_info *gi = to_gadget_info(item);
1633
1634         mutex_lock(&gi->lock);
1635         unregister_gadget(gi);
1636         mutex_unlock(&gi->lock);
1637 }
1638 EXPORT_SYMBOL_GPL(unregister_gadget_item);
1639
1640 static int __init gadget_cfs_init(void)
1641 {
1642         int ret;
1643
1644         config_group_init(&gadget_subsys.su_group);
1645
1646         ret = configfs_register_subsystem(&gadget_subsys);
1647         return ret;
1648 }
1649 module_init(gadget_cfs_init);
1650
1651 static void __exit gadget_cfs_exit(void)
1652 {
1653         configfs_unregister_subsystem(&gadget_subsys);
1654 }
1655 module_exit(gadget_cfs_exit);