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 static inline struct gadget_info *cfg_to_gadget_info(struct config_usb_cfg *cfg)
  77 {
  78         return container_of(cfg->c.cdev, struct gadget_info, cdev);
  79 }
  80
  81 struct gadget_strings {
  82         struct usb_gadget_strings stringtab_dev;
  83         struct usb_string strings[USB_GADGET_FIRST_AVAIL_IDX];
  84         char *manufacturer;
  85         char *product;
  86         char *serialnumber;
  87
  88         struct config_group group;
  89         struct list_head list;
  90 };
  91
  92 struct gadget_config_name {
  93         struct usb_gadget_strings stringtab_dev;
  94         struct usb_string strings;
  95         char *configuration;
  96
  97         struct config_group group;
  98         struct list_head list;
  99 };
 100
 101 #define USB_MAX_STRING_WITH_NULL_LEN    (USB_MAX_STRING_LEN+1)
 102
 103 static int usb_string_copy(const char *s, char **s_copy)
 104 {
 105         int ret;
 106         char *str;
 107         char *copy = *s_copy;
 108         ret = strlen(s);
 109         if (ret > USB_MAX_STRING_LEN)
 110                 return -EOVERFLOW;
 111
 112         if (copy) {
 113                 str = copy;
 114         } else {
 115                 str = kmalloc(USB_MAX_STRING_WITH_NULL_LEN, GFP_KERNEL);
 116                 if (!str)
 117                         return -ENOMEM;
 118         }
 119         strcpy(str, s);
 120         if (str[ret - 1] == '\n')
 121                 str[ret - 1] = '\0';
 122         *s_copy = str;
 123         return 0;
 124 }
 125
 126 #define GI_DEVICE_DESC_SIMPLE_R_u8(__name)      \
 127 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
 128                         char *page)     \
 129 {       \
 130         return sprintf(page, "0x%02x\n", \
 131                 to_gadget_info(item)->cdev.desc.__name); \
 132 }
 133
 134 #define GI_DEVICE_DESC_SIMPLE_R_u16(__name)     \
 135 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
 136                         char *page)     \
 137 {       \
 138         return sprintf(page, "0x%04x\n", \
 139                 le16_to_cpup(&to_gadget_info(item)->cdev.desc.__name)); \
 140 }
 141
 142
 143 #define GI_DEVICE_DESC_SIMPLE_W_u8(_name)               \
 144 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
 145                 const char *page, size_t len)           \
 146 {                                                       \
 147         u8 val;                                         \
 148         int ret;                                        \
 149         ret = kstrtou8(page, 0, &val);                  \
 150         if (ret)                                        \
 151                 return ret;                             \
 152         to_gadget_info(item)->cdev.desc._name = val;    \
 153         return len;                                     \
 154 }
 155
 156 #define GI_DEVICE_DESC_SIMPLE_W_u16(_name)      \
 157 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
 158                 const char *page, size_t len)           \
 159 {                                                       \
 160         u16 val;                                        \
 161         int ret;                                        \
 162         ret = kstrtou16(page, 0, &val);                 \
 163         if (ret)                                        \
 164                 return ret;                             \
 165         to_gadget_info(item)->cdev.desc._name = cpu_to_le16p(&val);     \
 166         return len;                                     \
 167 }
 168
 169 #define GI_DEVICE_DESC_SIMPLE_RW(_name, _type)  \
 170         GI_DEVICE_DESC_SIMPLE_R_##_type(_name)  \
 171         GI_DEVICE_DESC_SIMPLE_W_##_type(_name)
 172
 173 GI_DEVICE_DESC_SIMPLE_R_u16(bcdUSB);
 174 GI_DEVICE_DESC_SIMPLE_RW(bDeviceClass, u8);
 175 GI_DEVICE_DESC_SIMPLE_RW(bDeviceSubClass, u8);
 176 GI_DEVICE_DESC_SIMPLE_RW(bDeviceProtocol, u8);
 177 GI_DEVICE_DESC_SIMPLE_RW(bMaxPacketSize0, u8);
 178 GI_DEVICE_DESC_SIMPLE_RW(idVendor, u16);
 179 GI_DEVICE_DESC_SIMPLE_RW(idProduct, u16);
 180 GI_DEVICE_DESC_SIMPLE_R_u16(bcdDevice);
 181
 182 static ssize_t is_valid_bcd(u16 bcd_val)
 183 {
 184         if ((bcd_val & 0xf) > 9)
 185                 return -EINVAL;
 186         if (((bcd_val >> 4) & 0xf) > 9)
 187                 return -EINVAL;
 188         if (((bcd_val >> 8) & 0xf) > 9)
 189                 return -EINVAL;
 190         if (((bcd_val >> 12) & 0xf) > 9)
 191                 return -EINVAL;
 192         return 0;
 193 }
 194
 195 static ssize_t gadget_dev_desc_bcdDevice_store(struct config_item *item,
 196                 const char *page, size_t len)
 197 {
 198         u16 bcdDevice;
 199         int ret;
 200
 201         ret = kstrtou16(page, 0, &bcdDevice);
 202         if (ret)
 203                 return ret;
 204         ret = is_valid_bcd(bcdDevice);
 205         if (ret)
 206                 return ret;
 207
 208         to_gadget_info(item)->cdev.desc.bcdDevice = cpu_to_le16(bcdDevice);
 209         return len;
 210 }
 211
 212 static ssize_t gadget_dev_desc_bcdUSB_store(struct config_item *item,
 213                 const char *page, size_t len)
 214 {
 215         u16 bcdUSB;
 216         int ret;
 217
 218         ret = kstrtou16(page, 0, &bcdUSB);
 219         if (ret)
 220                 return ret;
 221         ret = is_valid_bcd(bcdUSB);
 222         if (ret)
 223                 return ret;
 224
 225         to_gadget_info(item)->cdev.desc.bcdUSB = cpu_to_le16(bcdUSB);
 226         return len;
 227 }
 228
 229 static ssize_t gadget_dev_desc_UDC_show(struct config_item *item, char *page)
 230 {
 231         struct gadget_info *gi = to_gadget_info(item);
 232         char *udc_name;
 233         int ret;
 234
 235         mutex_lock(&gi->lock);
 236         udc_name = gi->composite.gadget_driver.udc_name;
 237         ret = sprintf(page, "%s\n", udc_name ?: "");
 238         mutex_unlock(&gi->lock);
 239
 240         return ret;
 241 }
 242
 243 static int unregister_gadget(struct gadget_info *gi)
 244 {
 245         int ret;
 246
 247         if (!gi->composite.gadget_driver.udc_name)
 248                 return -ENODEV;
 249
 250         ret = usb_gadget_unregister_driver(&gi->composite.gadget_driver);
 251         if (ret)
 252                 return ret;
 253         kfree(gi->composite.gadget_driver.udc_name);
 254         gi->composite.gadget_driver.udc_name = NULL;
 255         return 0;
 256 }
 257
 258 static ssize_t gadget_dev_desc_UDC_store(struct config_item *item,
 259                 const char *page, size_t len)
 260 {
 261         struct gadget_info *gi = to_gadget_info(item);
 262         char *name;
 263         int ret;
 264
 265         if (strlen(page) < len)
 266                 return -EOVERFLOW;
 267
 268         name = kstrdup(page, GFP_KERNEL);
 269         if (!name)
 270                 return -ENOMEM;
 271         if (name[len - 1] == '\n')
 272                 name[len - 1] = '\0';
 273
 274         mutex_lock(&gi->lock);
 275
 276         if (!strlen(name)) {
 277                 ret = unregister_gadget(gi);
 278                 if (ret)
 279                         goto err;
 280                 kfree(name);
 281         } else {
 282                 if (gi->composite.gadget_driver.udc_name) {
 283                         ret = -EBUSY;
 284                         goto err;
 285                 }
 286                 gi->composite.gadget_driver.udc_name = name;
 287                 ret = usb_gadget_register_driver(&gi->composite.gadget_driver);
 288                 if (ret) {
 289                         gi->composite.gadget_driver.udc_name = NULL;
 290                         goto err;
 291                 }
 292         }
 293         mutex_unlock(&gi->lock);
 294         return len;
 295 err:
 296         kfree(name);
 297         mutex_unlock(&gi->lock);
 298         return ret;
 299 }
 300
 301 static ssize_t gadget_dev_desc_max_speed_show(struct config_item *item,
 302                                               char *page)
 303 {
 304         enum usb_device_speed speed = to_gadget_info(item)->composite.max_speed;
 305
 306         return sprintf(page, "%s\n", usb_speed_string(speed));
 307 }
 308
 309 static ssize_t gadget_dev_desc_max_speed_store(struct config_item *item,
 310                                                const char *page, size_t len)
 311 {
 312         struct gadget_info *gi = to_gadget_info(item);
 313
 314         mutex_lock(&gi->lock);
 315
 316         /* Prevent changing of max_speed after the driver is binded */
 317         if (gi->composite.gadget_driver.udc_name)
 318                 goto err;
 319
 320         if (strncmp(page, "super-speed-plus", 16) == 0)
 321                 gi->composite.max_speed = USB_SPEED_SUPER_PLUS;
 322         else if (strncmp(page, "super-speed", 11) == 0)
 323                 gi->composite.max_speed = USB_SPEED_SUPER;
 324         else if (strncmp(page, "high-speed", 10) == 0)
 325                 gi->composite.max_speed = USB_SPEED_HIGH;
 326         else if (strncmp(page, "full-speed", 10) == 0)
 327                 gi->composite.max_speed = USB_SPEED_FULL;
 328         else if (strncmp(page, "low-speed", 9) == 0)
 329                 gi->composite.max_speed = USB_SPEED_LOW;
 330         else
 331                 goto err;
 332
 333         gi->composite.gadget_driver.max_speed = gi->composite.max_speed;
 334
 335         mutex_unlock(&gi->lock);
 336         return len;
 337 err:
 338         mutex_unlock(&gi->lock);
 339         return -EINVAL;
 340 }
 341
 342 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceClass);
 343 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceSubClass);
 344 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceProtocol);
 345 CONFIGFS_ATTR(gadget_dev_desc_, bMaxPacketSize0);
 346 CONFIGFS_ATTR(gadget_dev_desc_, idVendor);
 347 CONFIGFS_ATTR(gadget_dev_desc_, idProduct);
 348 CONFIGFS_ATTR(gadget_dev_desc_, bcdDevice);
 349 CONFIGFS_ATTR(gadget_dev_desc_, bcdUSB);
 350 CONFIGFS_ATTR(gadget_dev_desc_, UDC);
 351 CONFIGFS_ATTR(gadget_dev_desc_, max_speed);
 352
 353 static struct configfs_attribute *gadget_root_attrs[] = {
 354         &gadget_dev_desc_attr_bDeviceClass,
 355         &gadget_dev_desc_attr_bDeviceSubClass,
 356         &gadget_dev_desc_attr_bDeviceProtocol,
 357         &gadget_dev_desc_attr_bMaxPacketSize0,
 358         &gadget_dev_desc_attr_idVendor,
 359         &gadget_dev_desc_attr_idProduct,
 360         &gadget_dev_desc_attr_bcdDevice,
 361         &gadget_dev_desc_attr_bcdUSB,
 362         &gadget_dev_desc_attr_UDC,
 363         &gadget_dev_desc_attr_max_speed,
 364         NULL,
 365 };
 366
 367 static inline struct gadget_strings *to_gadget_strings(struct config_item *item)
 368 {
 369         return container_of(to_config_group(item), struct gadget_strings,
 370                          group);
 371 }
 372
 373 static inline struct gadget_config_name *to_gadget_config_name(
 374                 struct config_item *item)
 375 {
 376         return container_of(to_config_group(item), struct gadget_config_name,
 377                          group);
 378 }
 379
 380 static inline struct usb_function_instance *to_usb_function_instance(
 381                 struct config_item *item)
 382 {
 383         return container_of(to_config_group(item),
 384                          struct usb_function_instance, group);
 385 }
 386
 387 static void gadget_info_attr_release(struct config_item *item)
 388 {
 389         struct gadget_info *gi = to_gadget_info(item);
 390
 391         WARN_ON(!list_empty(&gi->cdev.configs));
 392         WARN_ON(!list_empty(&gi->string_list));
 393         WARN_ON(!list_empty(&gi->available_func));
 394         kfree(gi->composite.gadget_driver.function);
 395         kfree(gi);
 396 }
 397
 398 static struct configfs_item_operations gadget_root_item_ops = {
 399         .release                = gadget_info_attr_release,
 400 };
 401
 402 static void gadget_config_attr_release(struct config_item *item)
 403 {
 404         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
 405
 406         WARN_ON(!list_empty(&cfg->c.functions));
 407         list_del(&cfg->c.list);
 408         kfree(cfg->c.label);
 409         kfree(cfg);
 410 }
 411
 412 static int config_usb_cfg_link(
 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 gadget_info *gi = cfg_to_gadget_info(cfg);
 418
 419         struct usb_function_instance *fi =
 420                         to_usb_function_instance(usb_func_ci);
 421         struct usb_function_instance *a_fi = NULL, *iter;
 422         struct usb_function *f;
 423         int ret;
 424
 425         mutex_lock(&gi->lock);
 426         /*
 427          * Make sure this function is from within our _this_ gadget and not
 428          * from another gadget or a random directory.
 429          * Also a function instance can only be linked once.
 430          */
 431         list_for_each_entry(iter, &gi->available_func, cfs_list) {
 432                 if (iter != fi)
 433                         continue;
 434                 a_fi = iter;
 435                 break;
 436         }
 437         if (!a_fi) {
 438                 ret = -EINVAL;
 439                 goto out;
 440         }
 441
 442         list_for_each_entry(f, &cfg->func_list, list) {
 443                 if (f->fi == fi) {
 444                         ret = -EEXIST;
 445                         goto out;
 446                 }
 447         }
 448
 449         f = usb_get_function(fi);
 450         if (IS_ERR(f)) {
 451                 ret = PTR_ERR(f);
 452                 goto out;
 453         }
 454
 455         /* stash the function until we bind it to the gadget */
 456         list_add_tail(&f->list, &cfg->func_list);
 457         ret = 0;
 458 out:
 459         mutex_unlock(&gi->lock);
 460         return ret;
 461 }
 462
 463 static void config_usb_cfg_unlink(
 464         struct config_item *usb_cfg_ci,
 465         struct config_item *usb_func_ci)
 466 {
 467         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
 468         struct gadget_info *gi = cfg_to_gadget_info(cfg);
 469
 470         struct usb_function_instance *fi =
 471                         to_usb_function_instance(usb_func_ci);
 472         struct usb_function *f;
 473
 474         /*
 475          * ideally I would like to forbid to unlink functions while a gadget is
 476          * bound to an UDC. Since this isn't possible at the moment, we simply
 477          * force an unbind, the function is available here and then we can
 478          * remove the function.
 479          */
 480         mutex_lock(&gi->lock);
 481         if (gi->composite.gadget_driver.udc_name)
 482                 unregister_gadget(gi);
 483         WARN_ON(gi->composite.gadget_driver.udc_name);
 484
 485         list_for_each_entry(f, &cfg->func_list, list) {
 486                 if (f->fi == fi) {
 487                         list_del(&f->list);
 488                         usb_put_function(f);
 489                         mutex_unlock(&gi->lock);
 490                         return;
 491                 }
 492         }
 493         mutex_unlock(&gi->lock);
 494         WARN(1, "Unable to locate function to unbind\n");
 495 }
 496
 497 static struct configfs_item_operations gadget_config_item_ops = {
 498         .release                = gadget_config_attr_release,
 499         .allow_link             = config_usb_cfg_link,
 500         .drop_link              = config_usb_cfg_unlink,
 501 };
 502
 503
 504 static ssize_t gadget_config_desc_MaxPower_show(struct config_item *item,
 505                 char *page)
 506 {
 507         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
 508
 509         return sprintf(page, "%u\n", cfg->c.MaxPower);
 510 }
 511
 512 static ssize_t gadget_config_desc_MaxPower_store(struct config_item *item,
 513                 const char *page, size_t len)
 514 {
 515         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
 516         u16 val;
 517         int ret;
 518         ret = kstrtou16(page, 0, &val);
 519         if (ret)
 520                 return ret;
 521         if (DIV_ROUND_UP(val, 8) > 0xff)
 522                 return -ERANGE;
 523         cfg->c.MaxPower = val;
 524         return len;
 525 }
 526
 527 static ssize_t gadget_config_desc_bmAttributes_show(struct config_item *item,
 528                 char *page)
 529 {
 530         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
 531
 532         return sprintf(page, "0x%02x\n", cfg->c.bmAttributes);
 533 }
 534
 535 static ssize_t gadget_config_desc_bmAttributes_store(struct config_item *item,
 536                 const char *page, size_t len)
 537 {
 538         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
 539         u8 val;
 540         int ret;
 541         ret = kstrtou8(page, 0, &val);
 542         if (ret)
 543                 return ret;
 544         if (!(val & USB_CONFIG_ATT_ONE))
 545                 return -EINVAL;
 546         if (val & ~(USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER |
 547                                 USB_CONFIG_ATT_WAKEUP))
 548                 return -EINVAL;
 549         cfg->c.bmAttributes = val;
 550         return len;
 551 }
 552
 553 CONFIGFS_ATTR(gadget_config_desc_, MaxPower);
 554 CONFIGFS_ATTR(gadget_config_desc_, bmAttributes);
 555
 556 static struct configfs_attribute *gadget_config_attrs[] = {
 557         &gadget_config_desc_attr_MaxPower,
 558         &gadget_config_desc_attr_bmAttributes,
 559         NULL,
 560 };
 561
 562 static const struct config_item_type gadget_config_type = {
 563         .ct_item_ops    = &gadget_config_item_ops,
 564         .ct_attrs       = gadget_config_attrs,
 565         .ct_owner       = THIS_MODULE,
 566 };
 567
 568 static const struct config_item_type gadget_root_type = {
 569         .ct_item_ops    = &gadget_root_item_ops,
 570         .ct_attrs       = gadget_root_attrs,
 571         .ct_owner       = THIS_MODULE,
 572 };
 573
 574 static void composite_init_dev(struct usb_composite_dev *cdev)
 575 {
 576         spin_lock_init(&cdev->lock);
 577         INIT_LIST_HEAD(&cdev->configs);
 578         INIT_LIST_HEAD(&cdev->gstrings);
 579 }
 580
 581 static struct config_group *function_make(
 582                 struct config_group *group,
 583                 const char *name)
 584 {
 585         struct gadget_info *gi;
 586         struct usb_function_instance *fi;
 587         char buf[MAX_NAME_LEN];
 588         char *func_name;
 589         char *instance_name;
 590         int ret;
 591
 592         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
 593         if (ret >= MAX_NAME_LEN)
 594                 return ERR_PTR(-ENAMETOOLONG);
 595
 596         func_name = buf;
 597         instance_name = strchr(func_name, '.');
 598         if (!instance_name) {
 599                 pr_err("Unable to locate . in FUNC.INSTANCE\n");
 600                 return ERR_PTR(-EINVAL);
 601         }
 602         *instance_name = '\0';
 603         instance_name++;
 604
 605         fi = usb_get_function_instance(func_name);
 606         if (IS_ERR(fi))
 607                 return ERR_CAST(fi);
 608
 609         ret = config_item_set_name(&fi->group.cg_item, "%s", name);
 610         if (ret) {
 611                 usb_put_function_instance(fi);
 612                 return ERR_PTR(ret);
 613         }
 614         if (fi->set_inst_name) {
 615                 ret = fi->set_inst_name(fi, instance_name);
 616                 if (ret) {
 617                         usb_put_function_instance(fi);
 618                         return ERR_PTR(ret);
 619                 }
 620         }
 621
 622         gi = container_of(group, struct gadget_info, functions_group);
 623
 624         mutex_lock(&gi->lock);
 625         list_add_tail(&fi->cfs_list, &gi->available_func);
 626         mutex_unlock(&gi->lock);
 627         return &fi->group;
 628 }
 629
 630 static void function_drop(
 631                 struct config_group *group,
 632                 struct config_item *item)
 633 {
 634         struct usb_function_instance *fi = to_usb_function_instance(item);
 635         struct gadget_info *gi;
 636
 637         gi = container_of(group, struct gadget_info, functions_group);
 638
 639         mutex_lock(&gi->lock);
 640         list_del(&fi->cfs_list);
 641         mutex_unlock(&gi->lock);
 642         config_item_put(item);
 643 }
 644
 645 static struct configfs_group_operations functions_ops = {
 646         .make_group     = &function_make,
 647         .drop_item      = &function_drop,
 648 };
 649
 650 static const struct config_item_type functions_type = {
 651         .ct_group_ops   = &functions_ops,
 652         .ct_owner       = THIS_MODULE,
 653 };
 654
 655 GS_STRINGS_RW(gadget_config_name, configuration);
 656
 657 static struct configfs_attribute *gadget_config_name_langid_attrs[] = {
 658         &gadget_config_name_attr_configuration,
 659         NULL,
 660 };
 661
 662 static void gadget_config_name_attr_release(struct config_item *item)
 663 {
 664         struct gadget_config_name *cn = to_gadget_config_name(item);
 665
 666         kfree(cn->configuration);
 667
 668         list_del(&cn->list);
 669         kfree(cn);
 670 }
 671
 672 USB_CONFIG_STRING_RW_OPS(gadget_config_name);
 673 USB_CONFIG_STRINGS_LANG(gadget_config_name, config_usb_cfg);
 674
 675 static struct config_group *config_desc_make(
 676                 struct config_group *group,
 677                 const char *name)
 678 {
 679         struct gadget_info *gi;
 680         struct config_usb_cfg *cfg;
 681         char buf[MAX_NAME_LEN];
 682         char *num_str;
 683         u8 num;
 684         int ret;
 685
 686         gi = container_of(group, struct gadget_info, configs_group);
 687         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
 688         if (ret >= MAX_NAME_LEN)
 689                 return ERR_PTR(-ENAMETOOLONG);
 690
 691         num_str = strchr(buf, '.');
 692         if (!num_str) {
 693                 pr_err("Unable to locate . in name.bConfigurationValue\n");
 694                 return ERR_PTR(-EINVAL);
 695         }
 696
 697         *num_str = '\0';
 698         num_str++;
 699
 700         if (!strlen(buf))
 701                 return ERR_PTR(-EINVAL);
 702
 703         ret = kstrtou8(num_str, 0, &num);
 704         if (ret)
 705                 return ERR_PTR(ret);
 706
 707         cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
 708         if (!cfg)
 709                 return ERR_PTR(-ENOMEM);
 710         cfg->c.label = kstrdup(buf, GFP_KERNEL);
 711         if (!cfg->c.label) {
 712                 ret = -ENOMEM;
 713                 goto err;
 714         }
 715         cfg->c.bConfigurationValue = num;
 716         cfg->c.MaxPower = CONFIG_USB_GADGET_VBUS_DRAW;
 717         cfg->c.bmAttributes = USB_CONFIG_ATT_ONE;
 718         INIT_LIST_HEAD(&cfg->string_list);
 719         INIT_LIST_HEAD(&cfg->func_list);
 720
 721         config_group_init_type_name(&cfg->group, name,
 722                                 &gadget_config_type);
 723
 724         config_group_init_type_name(&cfg->strings_group, "strings",
 725                         &gadget_config_name_strings_type);
 726         configfs_add_default_group(&cfg->strings_group, &cfg->group);
 727
 728         ret = usb_add_config_only(&gi->cdev, &cfg->c);
 729         if (ret)
 730                 goto err;
 731
 732         return &cfg->group;
 733 err:
 734         kfree(cfg->c.label);
 735         kfree(cfg);
 736         return ERR_PTR(ret);
 737 }
 738
 739 static void config_desc_drop(
 740                 struct config_group *group,
 741                 struct config_item *item)
 742 {
 743         config_item_put(item);
 744 }
 745
 746 static struct configfs_group_operations config_desc_ops = {
 747         .make_group     = &config_desc_make,
 748         .drop_item      = &config_desc_drop,
 749 };
 750
 751 static const struct config_item_type config_desc_type = {
 752         .ct_group_ops   = &config_desc_ops,
 753         .ct_owner       = THIS_MODULE,
 754 };
 755
 756 GS_STRINGS_RW(gadget_strings, manufacturer);
 757 GS_STRINGS_RW(gadget_strings, product);
 758 GS_STRINGS_RW(gadget_strings, serialnumber);
 759
 760 static struct configfs_attribute *gadget_strings_langid_attrs[] = {
 761         &gadget_strings_attr_manufacturer,
 762         &gadget_strings_attr_product,
 763         &gadget_strings_attr_serialnumber,
 764         NULL,
 765 };
 766
 767 static void gadget_strings_attr_release(struct config_item *item)
 768 {
 769         struct gadget_strings *gs = to_gadget_strings(item);
 770
 771         kfree(gs->manufacturer);
 772         kfree(gs->product);
 773         kfree(gs->serialnumber);
 774
 775         list_del(&gs->list);
 776         kfree(gs);
 777 }
 778
 779 USB_CONFIG_STRING_RW_OPS(gadget_strings);
 780 USB_CONFIG_STRINGS_LANG(gadget_strings, gadget_info);
 781
 782 static inline struct gadget_info *os_desc_item_to_gadget_info(
 783                 struct config_item *item)
 784 {
 785         return container_of(to_config_group(item),
 786                         struct gadget_info, os_desc_group);
 787 }
 788
 789 static ssize_t os_desc_use_show(struct config_item *item, char *page)
 790 {
 791         return sprintf(page, "%d\n",
 792                         os_desc_item_to_gadget_info(item)->use_os_desc);
 793 }
 794
 795 static ssize_t os_desc_use_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 ret;
 800         bool use;
 801
 802         mutex_lock(&gi->lock);
 803         ret = strtobool(page, &use);
 804         if (!ret) {
 805                 gi->use_os_desc = use;
 806                 ret = len;
 807         }
 808         mutex_unlock(&gi->lock);
 809
 810         return ret;
 811 }
 812
 813 static ssize_t os_desc_b_vendor_code_show(struct config_item *item, char *page)
 814 {
 815         return sprintf(page, "0x%02x\n",
 816                         os_desc_item_to_gadget_info(item)->b_vendor_code);
 817 }
 818
 819 static ssize_t os_desc_b_vendor_code_store(struct config_item *item,
 820                                            const char *page, size_t len)
 821 {
 822         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 823         int ret;
 824         u8 b_vendor_code;
 825
 826         mutex_lock(&gi->lock);
 827         ret = kstrtou8(page, 0, &b_vendor_code);
 828         if (!ret) {
 829                 gi->b_vendor_code = b_vendor_code;
 830                 ret = len;
 831         }
 832         mutex_unlock(&gi->lock);
 833
 834         return ret;
 835 }
 836
 837 static ssize_t os_desc_qw_sign_show(struct config_item *item, char *page)
 838 {
 839         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 840         int res;
 841
 842         res = utf16s_to_utf8s((wchar_t *) gi->qw_sign, OS_STRING_QW_SIGN_LEN,
 843                               UTF16_LITTLE_ENDIAN, page, PAGE_SIZE - 1);
 844         page[res++] = '\n';
 845
 846         return res;
 847 }
 848
 849 static ssize_t os_desc_qw_sign_store(struct config_item *item, const char *page,
 850                                      size_t len)
 851 {
 852         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 853         int res, l;
 854
 855         l = min((int)len, OS_STRING_QW_SIGN_LEN >> 1);
 856         if (page[l - 1] == '\n')
 857                 --l;
 858
 859         mutex_lock(&gi->lock);
 860         res = utf8s_to_utf16s(page, l,
 861                               UTF16_LITTLE_ENDIAN, (wchar_t *) gi->qw_sign,
 862                               OS_STRING_QW_SIGN_LEN);
 863         if (res > 0)
 864                 res = len;
 865         mutex_unlock(&gi->lock);
 866
 867         return res;
 868 }
 869
 870 CONFIGFS_ATTR(os_desc_, use);
 871 CONFIGFS_ATTR(os_desc_, b_vendor_code);
 872 CONFIGFS_ATTR(os_desc_, qw_sign);
 873
 874 static struct configfs_attribute *os_desc_attrs[] = {
 875         &os_desc_attr_use,
 876         &os_desc_attr_b_vendor_code,
 877         &os_desc_attr_qw_sign,
 878         NULL,
 879 };
 880
 881 static int os_desc_link(struct config_item *os_desc_ci,
 882                         struct config_item *usb_cfg_ci)
 883 {
 884         struct gadget_info *gi = os_desc_item_to_gadget_info(os_desc_ci);
 885         struct usb_composite_dev *cdev = &gi->cdev;
 886         struct config_usb_cfg *c_target = to_config_usb_cfg(usb_cfg_ci);
 887         struct usb_configuration *c = NULL, *iter;
 888         int ret;
 889
 890         mutex_lock(&gi->lock);
 891         list_for_each_entry(iter, &cdev->configs, list) {
 892                 if (iter != &c_target->c)
 893                         continue;
 894                 c = iter;
 895                 break;
 896         }
 897         if (!c) {
 898                 ret = -EINVAL;
 899                 goto out;
 900         }
 901
 902         if (cdev->os_desc_config) {
 903                 ret = -EBUSY;
 904                 goto out;
 905         }
 906
 907         cdev->os_desc_config = &c_target->c;
 908         ret = 0;
 909
 910 out:
 911         mutex_unlock(&gi->lock);
 912         return ret;
 913 }
 914
 915 static void os_desc_unlink(struct config_item *os_desc_ci,
 916                           struct config_item *usb_cfg_ci)
 917 {
 918         struct gadget_info *gi = os_desc_item_to_gadget_info(os_desc_ci);
 919         struct usb_composite_dev *cdev = &gi->cdev;
 920
 921         mutex_lock(&gi->lock);
 922         if (gi->composite.gadget_driver.udc_name)
 923                 unregister_gadget(gi);
 924         cdev->os_desc_config = NULL;
 925         WARN_ON(gi->composite.gadget_driver.udc_name);
 926         mutex_unlock(&gi->lock);
 927 }
 928
 929 static struct configfs_item_operations os_desc_ops = {
 930         .allow_link             = os_desc_link,
 931         .drop_link              = os_desc_unlink,
 932 };
 933
 934 static struct config_item_type os_desc_type = {
 935         .ct_item_ops    = &os_desc_ops,
 936         .ct_attrs       = os_desc_attrs,
 937         .ct_owner       = THIS_MODULE,
 938 };
 939
 940 static inline struct usb_os_desc_ext_prop
 941 *to_usb_os_desc_ext_prop(struct config_item *item)
 942 {
 943         return container_of(item, struct usb_os_desc_ext_prop, item);
 944 }
 945
 946 static ssize_t ext_prop_type_show(struct config_item *item, char *page)
 947 {
 948         return sprintf(page, "%d\n", to_usb_os_desc_ext_prop(item)->type);
 949 }
 950
 951 static ssize_t ext_prop_type_store(struct config_item *item,
 952                                    const char *page, size_t len)
 953 {
 954         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
 955         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
 956         u8 type;
 957         int ret;
 958
 959         if (desc->opts_mutex)
 960                 mutex_lock(desc->opts_mutex);
 961         ret = kstrtou8(page, 0, &type);
 962         if (ret)
 963                 goto end;
 964         if (type < USB_EXT_PROP_UNICODE || type > USB_EXT_PROP_UNICODE_MULTI) {
 965                 ret = -EINVAL;
 966                 goto end;
 967         }
 968
 969         if ((ext_prop->type == USB_EXT_PROP_BINARY ||
 970             ext_prop->type == USB_EXT_PROP_LE32 ||
 971             ext_prop->type == USB_EXT_PROP_BE32) &&
 972             (type == USB_EXT_PROP_UNICODE ||
 973             type == USB_EXT_PROP_UNICODE_ENV ||
 974             type == USB_EXT_PROP_UNICODE_LINK))
 975                 ext_prop->data_len <<= 1;
 976         else if ((ext_prop->type == USB_EXT_PROP_UNICODE ||
 977                    ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
 978                    ext_prop->type == USB_EXT_PROP_UNICODE_LINK) &&
 979                    (type == USB_EXT_PROP_BINARY ||
 980                    type == USB_EXT_PROP_LE32 ||
 981                    type == USB_EXT_PROP_BE32))
 982                 ext_prop->data_len >>= 1;
 983         ext_prop->type = type;
 984         ret = len;
 985
 986 end:
 987         if (desc->opts_mutex)
 988                 mutex_unlock(desc->opts_mutex);
 989         return ret;
 990 }
 991
 992 static ssize_t ext_prop_data_show(struct config_item *item, char *page)
 993 {
 994         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
 995         int len = ext_prop->data_len;
 996
 997         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
 998             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
 999             ext_prop->type == USB_EXT_PROP_UNICODE_LINK)
1000                 len >>= 1;
1001         memcpy(page, ext_prop->data, len);
1002
1003         return len;
1004 }
1005
1006 static ssize_t ext_prop_data_store(struct config_item *item,
1007                                    const char *page, size_t len)
1008 {
1009         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1010         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
1011         char *new_data;
1012         size_t ret_len = len;
1013
1014         if (page[len - 1] == '\n' || page[len - 1] == '\0')
1015                 --len;
1016         new_data = kmemdup(page, len, GFP_KERNEL);
1017         if (!new_data)
1018                 return -ENOMEM;
1019
1020         if (desc->opts_mutex)
1021                 mutex_lock(desc->opts_mutex);
1022         kfree(ext_prop->data);
1023         ext_prop->data = new_data;
1024         desc->ext_prop_len -= ext_prop->data_len;
1025         ext_prop->data_len = len;
1026         desc->ext_prop_len += ext_prop->data_len;
1027         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
1028             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
1029             ext_prop->type == USB_EXT_PROP_UNICODE_LINK) {
1030                 desc->ext_prop_len -= ext_prop->data_len;
1031                 ext_prop->data_len <<= 1;
1032                 ext_prop->data_len += 2;
1033                 desc->ext_prop_len += ext_prop->data_len;
1034         }
1035         if (desc->opts_mutex)
1036                 mutex_unlock(desc->opts_mutex);
1037         return ret_len;
1038 }
1039
1040 CONFIGFS_ATTR(ext_prop_, type);
1041 CONFIGFS_ATTR(ext_prop_, data);
1042
1043 static struct configfs_attribute *ext_prop_attrs[] = {
1044         &ext_prop_attr_type,
1045         &ext_prop_attr_data,
1046         NULL,
1047 };
1048
1049 static void usb_os_desc_ext_prop_release(struct config_item *item)
1050 {
1051         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1052
1053         kfree(ext_prop); /* frees a whole chunk */
1054 }
1055
1056 static struct configfs_item_operations ext_prop_ops = {
1057         .release                = usb_os_desc_ext_prop_release,
1058 };
1059
1060 static struct config_item *ext_prop_make(
1061                 struct config_group *group,
1062                 const char *name)
1063 {
1064         struct usb_os_desc_ext_prop *ext_prop;
1065         struct config_item_type *ext_prop_type;
1066         struct usb_os_desc *desc;
1067         char *vlabuf;
1068
1069         vla_group(data_chunk);
1070         vla_item(data_chunk, struct usb_os_desc_ext_prop, ext_prop, 1);
1071         vla_item(data_chunk, struct config_item_type, ext_prop_type, 1);
1072
1073         vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1074         if (!vlabuf)
1075                 return ERR_PTR(-ENOMEM);
1076
1077         ext_prop = vla_ptr(vlabuf, data_chunk, ext_prop);
1078         ext_prop_type = vla_ptr(vlabuf, data_chunk, ext_prop_type);
1079
1080         desc = container_of(group, struct usb_os_desc, group);
1081         ext_prop_type->ct_item_ops = &ext_prop_ops;
1082         ext_prop_type->ct_attrs = ext_prop_attrs;
1083         ext_prop_type->ct_owner = desc->owner;
1084
1085         config_item_init_type_name(&ext_prop->item, name, ext_prop_type);
1086
1087         ext_prop->name = kstrdup(name, GFP_KERNEL);
1088         if (!ext_prop->name) {
1089                 kfree(vlabuf);
1090                 return ERR_PTR(-ENOMEM);
1091         }
1092         desc->ext_prop_len += 14;
1093         ext_prop->name_len = 2 * strlen(ext_prop->name) + 2;
1094         if (desc->opts_mutex)
1095                 mutex_lock(desc->opts_mutex);
1096         desc->ext_prop_len += ext_prop->name_len;
1097         list_add_tail(&ext_prop->entry, &desc->ext_prop);
1098         ++desc->ext_prop_count;
1099         if (desc->opts_mutex)
1100                 mutex_unlock(desc->opts_mutex);
1101
1102         return &ext_prop->item;
1103 }
1104
1105 static void ext_prop_drop(struct config_group *group, struct config_item *item)
1106 {
1107         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1108         struct usb_os_desc *desc = to_usb_os_desc(&group->cg_item);
1109
1110         if (desc->opts_mutex)
1111                 mutex_lock(desc->opts_mutex);
1112         list_del(&ext_prop->entry);
1113         --desc->ext_prop_count;
1114         kfree(ext_prop->name);
1115         desc->ext_prop_len -= (ext_prop->name_len + ext_prop->data_len + 14);
1116         if (desc->opts_mutex)
1117                 mutex_unlock(desc->opts_mutex);
1118         config_item_put(item);
1119 }
1120
1121 static struct configfs_group_operations interf_grp_ops = {
1122         .make_item      = &ext_prop_make,
1123         .drop_item      = &ext_prop_drop,
1124 };
1125
1126 static ssize_t interf_grp_compatible_id_show(struct config_item *item,
1127                                              char *page)
1128 {
1129         memcpy(page, to_usb_os_desc(item)->ext_compat_id, 8);
1130         return 8;
1131 }
1132
1133 static ssize_t interf_grp_compatible_id_store(struct config_item *item,
1134                                               const char *page, size_t len)
1135 {
1136         struct usb_os_desc *desc = to_usb_os_desc(item);
1137         int l;
1138
1139         l = min_t(int, 8, len);
1140         if (page[l - 1] == '\n')
1141                 --l;
1142         if (desc->opts_mutex)
1143                 mutex_lock(desc->opts_mutex);
1144         memcpy(desc->ext_compat_id, page, l);
1145
1146         if (desc->opts_mutex)
1147                 mutex_unlock(desc->opts_mutex);
1148
1149         return len;
1150 }
1151
1152 static ssize_t interf_grp_sub_compatible_id_show(struct config_item *item,
1153                                                  char *page)
1154 {
1155         memcpy(page, to_usb_os_desc(item)->ext_compat_id + 8, 8);
1156         return 8;
1157 }
1158
1159 static ssize_t interf_grp_sub_compatible_id_store(struct config_item *item,
1160                                                   const char *page, size_t len)
1161 {
1162         struct usb_os_desc *desc = to_usb_os_desc(item);
1163         int l;
1164
1165         l = min_t(int, 8, len);
1166         if (page[l - 1] == '\n')
1167                 --l;
1168         if (desc->opts_mutex)
1169                 mutex_lock(desc->opts_mutex);
1170         memcpy(desc->ext_compat_id + 8, page, l);
1171
1172         if (desc->opts_mutex)
1173                 mutex_unlock(desc->opts_mutex);
1174
1175         return len;
1176 }
1177
1178 CONFIGFS_ATTR(interf_grp_, compatible_id);
1179 CONFIGFS_ATTR(interf_grp_, sub_compatible_id);
1180
1181 static struct configfs_attribute *interf_grp_attrs[] = {
1182         &interf_grp_attr_compatible_id,
1183         &interf_grp_attr_sub_compatible_id,
1184         NULL
1185 };
1186
1187 struct config_group *usb_os_desc_prepare_interf_dir(
1188                 struct config_group *parent,
1189                 int n_interf,
1190                 struct usb_os_desc **desc,
1191                 char **names,
1192                 struct module *owner)
1193 {
1194         struct config_group *os_desc_group;
1195         struct config_item_type *os_desc_type, *interface_type;
1196
1197         vla_group(data_chunk);
1198         vla_item(data_chunk, struct config_group, os_desc_group, 1);
1199         vla_item(data_chunk, struct config_item_type, os_desc_type, 1);
1200         vla_item(data_chunk, struct config_item_type, interface_type, 1);
1201
1202         char *vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1203         if (!vlabuf)
1204                 return ERR_PTR(-ENOMEM);
1205
1206         os_desc_group = vla_ptr(vlabuf, data_chunk, os_desc_group);
1207         os_desc_type = vla_ptr(vlabuf, data_chunk, os_desc_type);
1208         interface_type = vla_ptr(vlabuf, data_chunk, interface_type);
1209
1210         os_desc_type->ct_owner = owner;
1211         config_group_init_type_name(os_desc_group, "os_desc", os_desc_type);
1212         configfs_add_default_group(os_desc_group, parent);
1213
1214         interface_type->ct_group_ops = &interf_grp_ops;
1215         interface_type->ct_attrs = interf_grp_attrs;
1216         interface_type->ct_owner = owner;
1217
1218         while (n_interf--) {
1219                 struct usb_os_desc *d;
1220
1221                 d = desc[n_interf];
1222                 d->owner = owner;
1223                 config_group_init_type_name(&d->group, "", interface_type);
1224                 config_item_set_name(&d->group.cg_item, "interface.%s",
1225                                      names[n_interf]);
1226                 configfs_add_default_group(&d->group, os_desc_group);
1227         }
1228
1229         return os_desc_group;
1230 }
1231 EXPORT_SYMBOL(usb_os_desc_prepare_interf_dir);
1232
1233 static int configfs_do_nothing(struct usb_composite_dev *cdev)
1234 {
1235         WARN_ON(1);
1236         return -EINVAL;
1237 }
1238
1239 int composite_dev_prepare(struct usb_composite_driver *composite,
1240                 struct usb_composite_dev *dev);
1241
1242 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
1243                                   struct usb_ep *ep0);
1244
1245 static void purge_configs_funcs(struct gadget_info *gi)
1246 {
1247         struct usb_configuration        *c;
1248
1249         list_for_each_entry(c, &gi->cdev.configs, list) {
1250                 struct usb_function *f, *tmp;
1251                 struct config_usb_cfg *cfg;
1252
1253                 cfg = container_of(c, struct config_usb_cfg, c);
1254
1255                 list_for_each_entry_safe_reverse(f, tmp, &c->functions, list) {
1256
1257                         list_move(&f->list, &cfg->func_list);
1258                         if (f->unbind) {
1259                                 dev_dbg(&gi->cdev.gadget->dev,
1260                                         "unbind function '%s'/%p\n",
1261                                         f->name, f);
1262                                 f->unbind(c, f);
1263                         }
1264                 }
1265                 c->next_interface_id = 0;
1266                 memset(c->interface, 0, sizeof(c->interface));
1267                 c->superspeed_plus = 0;
1268                 c->superspeed = 0;
1269                 c->highspeed = 0;
1270                 c->fullspeed = 0;
1271         }
1272 }
1273
1274 static int configfs_composite_bind(struct usb_gadget *gadget,
1275                 struct usb_gadget_driver *gdriver)
1276 {
1277         struct usb_composite_driver     *composite = to_cdriver(gdriver);
1278         struct gadget_info              *gi = container_of(composite,
1279                                                 struct gadget_info, composite);
1280         struct usb_composite_dev        *cdev = &gi->cdev;
1281         struct usb_configuration        *c;
1282         struct usb_string               *s;
1283         unsigned                        i;
1284         int                             ret;
1285
1286         /* the gi->lock is hold by the caller */
1287         gi->unbind = 0;
1288         cdev->gadget = gadget;
1289         set_gadget_data(gadget, cdev);
1290         ret = composite_dev_prepare(composite, cdev);
1291         if (ret)
1292                 return ret;
1293         /* and now the gadget bind */
1294         ret = -EINVAL;
1295
1296         if (list_empty(&gi->cdev.configs)) {
1297                 pr_err("Need at least one configuration in %s.\n",
1298                                 gi->composite.name);
1299                 goto err_comp_cleanup;
1300         }
1301
1302
1303         list_for_each_entry(c, &gi->cdev.configs, list) {
1304                 struct config_usb_cfg *cfg;
1305
1306                 cfg = container_of(c, struct config_usb_cfg, c);
1307                 if (list_empty(&cfg->func_list)) {
1308                         pr_err("Config %s/%d of %s needs at least one function.\n",
1309                               c->label, c->bConfigurationValue,
1310                               gi->composite.name);
1311                         goto err_comp_cleanup;
1312                 }
1313         }
1314
1315         /* init all strings */
1316         if (!list_empty(&gi->string_list)) {
1317                 struct gadget_strings *gs;
1318
1319                 i = 0;
1320                 list_for_each_entry(gs, &gi->string_list, list) {
1321
1322                         gi->gstrings[i] = &gs->stringtab_dev;
1323                         gs->stringtab_dev.strings = gs->strings;
1324                         gs->strings[USB_GADGET_MANUFACTURER_IDX].s =
1325                                 gs->manufacturer;
1326                         gs->strings[USB_GADGET_PRODUCT_IDX].s = gs->product;
1327                         gs->strings[USB_GADGET_SERIAL_IDX].s = gs->serialnumber;
1328                         i++;
1329                 }
1330                 gi->gstrings[i] = NULL;
1331                 s = usb_gstrings_attach(&gi->cdev, gi->gstrings,
1332                                 USB_GADGET_FIRST_AVAIL_IDX);
1333                 if (IS_ERR(s)) {
1334                         ret = PTR_ERR(s);
1335                         goto err_comp_cleanup;
1336                 }
1337
1338                 gi->cdev.desc.iManufacturer = s[USB_GADGET_MANUFACTURER_IDX].id;
1339                 gi->cdev.desc.iProduct = s[USB_GADGET_PRODUCT_IDX].id;
1340                 gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
1341         }
1342
1343         if (gi->use_os_desc) {
1344                 cdev->use_os_string = true;
1345                 cdev->b_vendor_code = gi->b_vendor_code;
1346                 memcpy(cdev->qw_sign, gi->qw_sign, OS_STRING_QW_SIGN_LEN);
1347         }
1348
1349         if (gadget_is_otg(gadget) && !otg_desc[0]) {
1350                 struct usb_descriptor_header *usb_desc;
1351
1352                 usb_desc = usb_otg_descriptor_alloc(gadget);
1353                 if (!usb_desc) {
1354                         ret = -ENOMEM;
1355                         goto err_comp_cleanup;
1356                 }
1357                 usb_otg_descriptor_init(gadget, usb_desc);
1358                 otg_desc[0] = usb_desc;
1359                 otg_desc[1] = NULL;
1360         }
1361
1362         /* Go through all configs, attach all functions */
1363         list_for_each_entry(c, &gi->cdev.configs, list) {
1364                 struct config_usb_cfg *cfg;
1365                 struct usb_function *f;
1366                 struct usb_function *tmp;
1367                 struct gadget_config_name *cn;
1368
1369                 if (gadget_is_otg(gadget))
1370                         c->descriptors = otg_desc;
1371
1372                 cfg = container_of(c, struct config_usb_cfg, c);
1373                 if (!list_empty(&cfg->string_list)) {
1374                         i = 0;
1375                         list_for_each_entry(cn, &cfg->string_list, list) {
1376                                 cfg->gstrings[i] = &cn->stringtab_dev;
1377                                 cn->stringtab_dev.strings = &cn->strings;
1378                                 cn->strings.s = cn->configuration;
1379                                 i++;
1380                         }
1381                         cfg->gstrings[i] = NULL;
1382                         s = usb_gstrings_attach(&gi->cdev, cfg->gstrings, 1);
1383                         if (IS_ERR(s)) {
1384                                 ret = PTR_ERR(s);
1385                                 goto err_comp_cleanup;
1386                         }
1387                         c->iConfiguration = s[0].id;
1388                 }
1389
1390                 list_for_each_entry_safe(f, tmp, &cfg->func_list, list) {
1391                         list_del(&f->list);
1392                         ret = usb_add_function(c, f);
1393                         if (ret) {
1394                                 list_add(&f->list, &cfg->func_list);
1395                                 goto err_purge_funcs;
1396                         }
1397                 }
1398                 ret = usb_gadget_check_config(cdev->gadget);
1399                 if (ret)
1400                         goto err_purge_funcs;
1401
1402                 usb_ep_autoconfig_reset(cdev->gadget);
1403         }
1404         if (cdev->use_os_string) {
1405                 ret = composite_os_desc_req_prepare(cdev, gadget->ep0);
1406                 if (ret)
1407                         goto err_purge_funcs;
1408         }
1409
1410         usb_ep_autoconfig_reset(cdev->gadget);
1411         return 0;
1412
1413 err_purge_funcs:
1414         purge_configs_funcs(gi);
1415 err_comp_cleanup:
1416         composite_dev_cleanup(cdev);
1417         return ret;
1418 }
1419
1420 static void configfs_composite_unbind(struct usb_gadget *gadget)
1421 {
1422         struct usb_composite_dev        *cdev;
1423         struct gadget_info              *gi;
1424         unsigned long flags;
1425
1426         /* the gi->lock is hold by the caller */
1427
1428         cdev = get_gadget_data(gadget);
1429         gi = container_of(cdev, struct gadget_info, cdev);
1430         spin_lock_irqsave(&gi->spinlock, flags);
1431         gi->unbind = 1;
1432         spin_unlock_irqrestore(&gi->spinlock, flags);
1433
1434         kfree(otg_desc[0]);
1435         otg_desc[0] = NULL;
1436         purge_configs_funcs(gi);
1437         composite_dev_cleanup(cdev);
1438         usb_ep_autoconfig_reset(cdev->gadget);
1439         spin_lock_irqsave(&gi->spinlock, flags);
1440         cdev->gadget = NULL;
1441         cdev->deactivations = 0;
1442         gadget->deactivated = false;
1443         set_gadget_data(gadget, NULL);
1444         spin_unlock_irqrestore(&gi->spinlock, flags);
1445 }
1446
1447 static int configfs_composite_setup(struct usb_gadget *gadget,
1448                 const struct usb_ctrlrequest *ctrl)
1449 {
1450         struct usb_composite_dev *cdev;
1451         struct gadget_info *gi;
1452         unsigned long flags;
1453         int ret;
1454
1455         cdev = get_gadget_data(gadget);
1456         if (!cdev)
1457                 return 0;
1458
1459         gi = container_of(cdev, struct gadget_info, cdev);
1460         spin_lock_irqsave(&gi->spinlock, flags);
1461         cdev = get_gadget_data(gadget);
1462         if (!cdev || gi->unbind) {
1463                 spin_unlock_irqrestore(&gi->spinlock, flags);
1464                 return 0;
1465         }
1466
1467         ret = composite_setup(gadget, ctrl);
1468         spin_unlock_irqrestore(&gi->spinlock, flags);
1469         return ret;
1470 }
1471
1472 static void configfs_composite_disconnect(struct usb_gadget *gadget)
1473 {
1474         struct usb_composite_dev *cdev;
1475         struct gadget_info *gi;
1476         unsigned long flags;
1477
1478         cdev = get_gadget_data(gadget);
1479         if (!cdev)
1480                 return;
1481
1482         gi = container_of(cdev, struct gadget_info, cdev);
1483         spin_lock_irqsave(&gi->spinlock, flags);
1484         cdev = get_gadget_data(gadget);
1485         if (!cdev || gi->unbind) {
1486                 spin_unlock_irqrestore(&gi->spinlock, flags);
1487                 return;
1488         }
1489
1490         composite_disconnect(gadget);
1491         spin_unlock_irqrestore(&gi->spinlock, flags);
1492 }
1493
1494 static void configfs_composite_reset(struct usb_gadget *gadget)
1495 {
1496         struct usb_composite_dev *cdev;
1497         struct gadget_info *gi;
1498         unsigned long flags;
1499
1500         cdev = get_gadget_data(gadget);
1501         if (!cdev)
1502                 return;
1503
1504         gi = container_of(cdev, struct gadget_info, cdev);
1505         spin_lock_irqsave(&gi->spinlock, flags);
1506         cdev = get_gadget_data(gadget);
1507         if (!cdev || gi->unbind) {
1508                 spin_unlock_irqrestore(&gi->spinlock, flags);
1509                 return;
1510         }
1511
1512         composite_reset(gadget);
1513         spin_unlock_irqrestore(&gi->spinlock, flags);
1514 }
1515
1516 static void configfs_composite_suspend(struct usb_gadget *gadget)
1517 {
1518         struct usb_composite_dev *cdev;
1519         struct gadget_info *gi;
1520         unsigned long flags;
1521
1522         cdev = get_gadget_data(gadget);
1523         if (!cdev)
1524                 return;
1525
1526         gi = container_of(cdev, struct gadget_info, cdev);
1527         spin_lock_irqsave(&gi->spinlock, flags);
1528         cdev = get_gadget_data(gadget);
1529         if (!cdev || gi->unbind) {
1530                 spin_unlock_irqrestore(&gi->spinlock, flags);
1531                 return;
1532         }
1533
1534         composite_suspend(gadget);
1535         spin_unlock_irqrestore(&gi->spinlock, flags);
1536 }
1537
1538 static void configfs_composite_resume(struct usb_gadget *gadget)
1539 {
1540         struct usb_composite_dev *cdev;
1541         struct gadget_info *gi;
1542         unsigned long flags;
1543
1544         cdev = get_gadget_data(gadget);
1545         if (!cdev)
1546                 return;
1547
1548         gi = container_of(cdev, struct gadget_info, cdev);
1549         spin_lock_irqsave(&gi->spinlock, flags);
1550         cdev = get_gadget_data(gadget);
1551         if (!cdev || gi->unbind) {
1552                 spin_unlock_irqrestore(&gi->spinlock, flags);
1553                 return;
1554         }
1555
1556         composite_resume(gadget);
1557         spin_unlock_irqrestore(&gi->spinlock, flags);
1558 }
1559
1560 static const struct usb_gadget_driver configfs_driver_template = {
1561         .bind           = configfs_composite_bind,
1562         .unbind         = configfs_composite_unbind,
1563
1564         .setup          = configfs_composite_setup,
1565         .reset          = configfs_composite_reset,
1566         .disconnect     = configfs_composite_disconnect,
1567
1568         .suspend        = configfs_composite_suspend,
1569         .resume         = configfs_composite_resume,
1570
1571         .max_speed      = USB_SPEED_SUPER_PLUS,
1572         .driver = {
1573                 .owner          = THIS_MODULE,
1574                 .name           = "configfs-gadget",
1575         },
1576         .match_existing_only = 1,
1577 };
1578
1579 static struct config_group *gadgets_make(
1580                 struct config_group *group,
1581                 const char *name)
1582 {
1583         struct gadget_info *gi;
1584
1585         gi = kzalloc(sizeof(*gi), GFP_KERNEL);
1586         if (!gi)
1587                 return ERR_PTR(-ENOMEM);
1588
1589         config_group_init_type_name(&gi->group, name, &gadget_root_type);
1590
1591         config_group_init_type_name(&gi->functions_group, "functions",
1592                         &functions_type);
1593         configfs_add_default_group(&gi->functions_group, &gi->group);
1594
1595         config_group_init_type_name(&gi->configs_group, "configs",
1596                         &config_desc_type);
1597         configfs_add_default_group(&gi->configs_group, &gi->group);
1598
1599         config_group_init_type_name(&gi->strings_group, "strings",
1600                         &gadget_strings_strings_type);
1601         configfs_add_default_group(&gi->strings_group, &gi->group);
1602
1603         config_group_init_type_name(&gi->os_desc_group, "os_desc",
1604                         &os_desc_type);
1605         configfs_add_default_group(&gi->os_desc_group, &gi->group);
1606
1607         gi->composite.bind = configfs_do_nothing;
1608         gi->composite.unbind = configfs_do_nothing;
1609         gi->composite.suspend = NULL;
1610         gi->composite.resume = NULL;
1611         gi->composite.max_speed = USB_SPEED_SUPER_PLUS;
1612
1613         spin_lock_init(&gi->spinlock);
1614         mutex_init(&gi->lock);
1615         INIT_LIST_HEAD(&gi->string_list);
1616         INIT_LIST_HEAD(&gi->available_func);
1617
1618         composite_init_dev(&gi->cdev);
1619         gi->cdev.desc.bLength = USB_DT_DEVICE_SIZE;
1620         gi->cdev.desc.bDescriptorType = USB_DT_DEVICE;
1621         gi->cdev.desc.bcdDevice = cpu_to_le16(get_default_bcdDevice());
1622
1623         gi->composite.gadget_driver = configfs_driver_template;
1624
1625         gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
1626         gi->composite.name = gi->composite.gadget_driver.function;
1627
1628         if (!gi->composite.gadget_driver.function)
1629                 goto err;
1630
1631         return &gi->group;
1632 err:
1633         kfree(gi);
1634         return ERR_PTR(-ENOMEM);
1635 }
1636
1637 static void gadgets_drop(struct config_group *group, struct config_item *item)
1638 {
1639         config_item_put(item);
1640 }
1641
1642 static struct configfs_group_operations gadgets_ops = {
1643         .make_group     = &gadgets_make,
1644         .drop_item      = &gadgets_drop,
1645 };
1646
1647 static const struct config_item_type gadgets_type = {
1648         .ct_group_ops   = &gadgets_ops,
1649         .ct_owner       = THIS_MODULE,
1650 };
1651
1652 static struct configfs_subsystem gadget_subsys = {
1653         .su_group = {
1654                 .cg_item = {
1655                         .ci_namebuf = "usb_gadget",
1656                         .ci_type = &gadgets_type,
1657                 },
1658         },
1659         .su_mutex = __MUTEX_INITIALIZER(gadget_subsys.su_mutex),
1660 };
1661
1662 void unregister_gadget_item(struct config_item *item)
1663 {
1664         struct gadget_info *gi = to_gadget_info(item);
1665
1666         mutex_lock(&gi->lock);
1667         unregister_gadget(gi);
1668         mutex_unlock(&gi->lock);
1669 }
1670 EXPORT_SYMBOL_GPL(unregister_gadget_item);
1671
1672 static int __init gadget_cfs_init(void)
1673 {
1674         int ret;
1675
1676         config_group_init(&gadget_subsys.su_group);
1677
1678         ret = configfs_register_subsystem(&gadget_subsys);
1679         return ret;
1680 }
1681 module_init(gadget_cfs_init);
1682
1683 static void __exit gadget_cfs_exit(void)
1684 {
1685         configfs_unregister_subsystem(&gadget_subsys);
1686 }
1687 module_exit(gadget_cfs_exit);