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         unsigned primary_lang;
  17         unsigned sub_lang;
  18         u16 num;
  19         int ret;
  20
  21         ret = kstrtou16(name, 0, &num);
  22         if (ret)
  23                 return ret;
  24
  25         primary_lang = num & 0x3ff;
  26         sub_lang = num >> 10;
  27
  28         /* simple sanity check for valid langid */
  29         switch (primary_lang) {
  30         case 0:
  31         case 0x62 ... 0xfe:
  32         case 0x100 ... 0x3ff:
  33                 return -EINVAL;
  34         }
  35         if (!sub_lang)
  36                 return -EINVAL;
  37
  38         stringtab_dev->language = num;
  39         return 0;
  40 }
  41
  42 #define MAX_NAME_LEN    40
  43 #define MAX_USB_STRING_LANGS 2
  44
  45 static const struct usb_descriptor_header *otg_desc[2];
  46
  47 struct gadget_info {
  48         struct config_group group;
  49         struct config_group functions_group;
  50         struct config_group configs_group;
  51         struct config_group strings_group;
  52         struct config_group os_desc_group;
  53
  54         struct mutex lock;
  55         struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
  56         struct list_head string_list;
  57         struct list_head available_func;
  58
  59         struct usb_composite_driver composite;
  60         struct usb_composite_dev cdev;
  61         bool use_os_desc;
  62         char b_vendor_code;
  63         char qw_sign[OS_STRING_QW_SIGN_LEN];
  64         spinlock_t spinlock;
  65         bool unbind;
  66 };
  67
  68 static inline struct gadget_info *to_gadget_info(struct config_item *item)
  69 {
  70          return container_of(to_config_group(item), struct gadget_info, group);
  71 }
  72
  73 struct config_usb_cfg {
  74         struct config_group group;
  75         struct config_group strings_group;
  76         struct list_head string_list;
  77         struct usb_configuration c;
  78         struct list_head func_list;
  79         struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
  80 };
  81
  82 static inline struct config_usb_cfg *to_config_usb_cfg(struct config_item *item)
  83 {
  84         return container_of(to_config_group(item), struct config_usb_cfg,
  85                         group);
  86 }
  87
  88 struct gadget_strings {
  89         struct usb_gadget_strings stringtab_dev;
  90         struct usb_string strings[USB_GADGET_FIRST_AVAIL_IDX];
  91         char *manufacturer;
  92         char *product;
  93         char *serialnumber;
  94
  95         struct config_group group;
  96         struct list_head list;
  97 };
  98
  99 struct os_desc {
 100         struct config_group group;
 101 };
 102
 103 struct gadget_config_name {
 104         struct usb_gadget_strings stringtab_dev;
 105         struct usb_string strings;
 106         char *configuration;
 107
 108         struct config_group group;
 109         struct list_head list;
 110 };
 111
 112 static int usb_string_copy(const char *s, char **s_copy)
 113 {
 114         int ret;
 115         char *str;
 116         char *copy = *s_copy;
 117         ret = strlen(s);
 118         if (ret > 126)
 119                 return -EOVERFLOW;
 120
 121         str = kstrdup(s, GFP_KERNEL);
 122         if (!str)
 123                 return -ENOMEM;
 124         if (str[ret - 1] == '\n')
 125                 str[ret - 1] = '\0';
 126         kfree(copy);
 127         *s_copy = str;
 128         return 0;
 129 }
 130
 131 #define GI_DEVICE_DESC_SIMPLE_R_u8(__name)      \
 132 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
 133                         char *page)     \
 134 {       \
 135         return sprintf(page, "0x%02x\n", \
 136                 to_gadget_info(item)->cdev.desc.__name); \
 137 }
 138
 139 #define GI_DEVICE_DESC_SIMPLE_R_u16(__name)     \
 140 static ssize_t gadget_dev_desc_##__name##_show(struct config_item *item, \
 141                         char *page)     \
 142 {       \
 143         return sprintf(page, "0x%04x\n", \
 144                 le16_to_cpup(&to_gadget_info(item)->cdev.desc.__name)); \
 145 }
 146
 147
 148 #define GI_DEVICE_DESC_SIMPLE_W_u8(_name)               \
 149 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
 150                 const char *page, size_t len)           \
 151 {                                                       \
 152         u8 val;                                         \
 153         int ret;                                        \
 154         ret = kstrtou8(page, 0, &val);                  \
 155         if (ret)                                        \
 156                 return ret;                             \
 157         to_gadget_info(item)->cdev.desc._name = val;    \
 158         return len;                                     \
 159 }
 160
 161 #define GI_DEVICE_DESC_SIMPLE_W_u16(_name)      \
 162 static ssize_t gadget_dev_desc_##_name##_store(struct config_item *item, \
 163                 const char *page, size_t len)           \
 164 {                                                       \
 165         u16 val;                                        \
 166         int ret;                                        \
 167         ret = kstrtou16(page, 0, &val);                 \
 168         if (ret)                                        \
 169                 return ret;                             \
 170         to_gadget_info(item)->cdev.desc._name = cpu_to_le16p(&val);     \
 171         return len;                                     \
 172 }
 173
 174 #define GI_DEVICE_DESC_SIMPLE_RW(_name, _type)  \
 175         GI_DEVICE_DESC_SIMPLE_R_##_type(_name)  \
 176         GI_DEVICE_DESC_SIMPLE_W_##_type(_name)
 177
 178 GI_DEVICE_DESC_SIMPLE_R_u16(bcdUSB);
 179 GI_DEVICE_DESC_SIMPLE_RW(bDeviceClass, u8);
 180 GI_DEVICE_DESC_SIMPLE_RW(bDeviceSubClass, u8);
 181 GI_DEVICE_DESC_SIMPLE_RW(bDeviceProtocol, u8);
 182 GI_DEVICE_DESC_SIMPLE_RW(bMaxPacketSize0, u8);
 183 GI_DEVICE_DESC_SIMPLE_RW(idVendor, u16);
 184 GI_DEVICE_DESC_SIMPLE_RW(idProduct, u16);
 185 GI_DEVICE_DESC_SIMPLE_R_u16(bcdDevice);
 186
 187 static ssize_t is_valid_bcd(u16 bcd_val)
 188 {
 189         if ((bcd_val & 0xf) > 9)
 190                 return -EINVAL;
 191         if (((bcd_val >> 4) & 0xf) > 9)
 192                 return -EINVAL;
 193         if (((bcd_val >> 8) & 0xf) > 9)
 194                 return -EINVAL;
 195         if (((bcd_val >> 12) & 0xf) > 9)
 196                 return -EINVAL;
 197         return 0;
 198 }
 199
 200 static ssize_t gadget_dev_desc_bcdDevice_store(struct config_item *item,
 201                 const char *page, size_t len)
 202 {
 203         u16 bcdDevice;
 204         int ret;
 205
 206         ret = kstrtou16(page, 0, &bcdDevice);
 207         if (ret)
 208                 return ret;
 209         ret = is_valid_bcd(bcdDevice);
 210         if (ret)
 211                 return ret;
 212
 213         to_gadget_info(item)->cdev.desc.bcdDevice = cpu_to_le16(bcdDevice);
 214         return len;
 215 }
 216
 217 static ssize_t gadget_dev_desc_bcdUSB_store(struct config_item *item,
 218                 const char *page, size_t len)
 219 {
 220         u16 bcdUSB;
 221         int ret;
 222
 223         ret = kstrtou16(page, 0, &bcdUSB);
 224         if (ret)
 225                 return ret;
 226         ret = is_valid_bcd(bcdUSB);
 227         if (ret)
 228                 return ret;
 229
 230         to_gadget_info(item)->cdev.desc.bcdUSB = cpu_to_le16(bcdUSB);
 231         return len;
 232 }
 233
 234 static ssize_t gadget_dev_desc_UDC_show(struct config_item *item, char *page)
 235 {
 236         char *udc_name = to_gadget_info(item)->composite.gadget_driver.udc_name;
 237
 238         return sprintf(page, "%s\n", udc_name ?: "");
 239 }
 240
 241 static int unregister_gadget(struct gadget_info *gi)
 242 {
 243         int ret;
 244
 245         if (!gi->composite.gadget_driver.udc_name)
 246                 return -ENODEV;
 247
 248         ret = usb_gadget_unregister_driver(&gi->composite.gadget_driver);
 249         if (ret)
 250                 return ret;
 251         kfree(gi->composite.gadget_driver.udc_name);
 252         gi->composite.gadget_driver.udc_name = NULL;
 253         return 0;
 254 }
 255
 256 static ssize_t gadget_dev_desc_UDC_store(struct config_item *item,
 257                 const char *page, size_t len)
 258 {
 259         struct gadget_info *gi = to_gadget_info(item);
 260         char *name;
 261         int ret;
 262
 263         name = kstrdup(page, GFP_KERNEL);
 264         if (!name)
 265                 return -ENOMEM;
 266         if (name[len - 1] == '\n')
 267                 name[len - 1] = '\0';
 268
 269         mutex_lock(&gi->lock);
 270
 271         if (!strlen(name)) {
 272                 ret = unregister_gadget(gi);
 273                 if (ret)
 274                         goto err;
 275                 kfree(name);
 276         } else {
 277                 if (gi->composite.gadget_driver.udc_name) {
 278                         ret = -EBUSY;
 279                         goto err;
 280                 }
 281                 gi->composite.gadget_driver.udc_name = name;
 282                 ret = usb_gadget_probe_driver(&gi->composite.gadget_driver);
 283                 if (ret) {
 284                         gi->composite.gadget_driver.udc_name = NULL;
 285                         goto err;
 286                 }
 287         }
 288         mutex_unlock(&gi->lock);
 289         return len;
 290 err:
 291         kfree(name);
 292         mutex_unlock(&gi->lock);
 293         return ret;
 294 }
 295
 296 static ssize_t gadget_dev_desc_max_speed_show(struct config_item *item,
 297                                               char *page)
 298 {
 299         enum usb_device_speed speed = to_gadget_info(item)->composite.max_speed;
 300
 301         return sprintf(page, "%s\n", usb_speed_string(speed));
 302 }
 303
 304 static ssize_t gadget_dev_desc_max_speed_store(struct config_item *item,
 305                                                const char *page, size_t len)
 306 {
 307         struct gadget_info *gi = to_gadget_info(item);
 308
 309         mutex_lock(&gi->lock);
 310
 311         /* Prevent changing of max_speed after the driver is binded */
 312         if (gi->composite.gadget_driver.udc_name)
 313                 goto err;
 314
 315         if (strncmp(page, "super-speed-plus", 16) == 0)
 316                 gi->composite.max_speed = USB_SPEED_SUPER_PLUS;
 317         else if (strncmp(page, "super-speed", 11) == 0)
 318                 gi->composite.max_speed = USB_SPEED_SUPER;
 319         else if (strncmp(page, "high-speed", 10) == 0)
 320                 gi->composite.max_speed = USB_SPEED_HIGH;
 321         else if (strncmp(page, "full-speed", 10) == 0)
 322                 gi->composite.max_speed = USB_SPEED_FULL;
 323         else if (strncmp(page, "low-speed", 9) == 0)
 324                 gi->composite.max_speed = USB_SPEED_LOW;
 325         else
 326                 goto err;
 327
 328         gi->composite.gadget_driver.max_speed = gi->composite.max_speed;
 329
 330         mutex_unlock(&gi->lock);
 331         return len;
 332 err:
 333         mutex_unlock(&gi->lock);
 334         return -EINVAL;
 335 }
 336
 337 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceClass);
 338 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceSubClass);
 339 CONFIGFS_ATTR(gadget_dev_desc_, bDeviceProtocol);
 340 CONFIGFS_ATTR(gadget_dev_desc_, bMaxPacketSize0);
 341 CONFIGFS_ATTR(gadget_dev_desc_, idVendor);
 342 CONFIGFS_ATTR(gadget_dev_desc_, idProduct);
 343 CONFIGFS_ATTR(gadget_dev_desc_, bcdDevice);
 344 CONFIGFS_ATTR(gadget_dev_desc_, bcdUSB);
 345 CONFIGFS_ATTR(gadget_dev_desc_, UDC);
 346 CONFIGFS_ATTR(gadget_dev_desc_, max_speed);
 347
 348 static struct configfs_attribute *gadget_root_attrs[] = {
 349         &gadget_dev_desc_attr_bDeviceClass,
 350         &gadget_dev_desc_attr_bDeviceSubClass,
 351         &gadget_dev_desc_attr_bDeviceProtocol,
 352         &gadget_dev_desc_attr_bMaxPacketSize0,
 353         &gadget_dev_desc_attr_idVendor,
 354         &gadget_dev_desc_attr_idProduct,
 355         &gadget_dev_desc_attr_bcdDevice,
 356         &gadget_dev_desc_attr_bcdUSB,
 357         &gadget_dev_desc_attr_UDC,
 358         &gadget_dev_desc_attr_max_speed,
 359         NULL,
 360 };
 361
 362 static inline struct gadget_strings *to_gadget_strings(struct config_item *item)
 363 {
 364          return container_of(to_config_group(item), struct gadget_strings,
 365                          group);
 366 }
 367
 368 static inline struct gadget_config_name *to_gadget_config_name(
 369                 struct config_item *item)
 370 {
 371          return container_of(to_config_group(item), struct gadget_config_name,
 372                          group);
 373 }
 374
 375 static inline struct usb_function_instance *to_usb_function_instance(
 376                 struct config_item *item)
 377 {
 378          return container_of(to_config_group(item),
 379                          struct usb_function_instance, group);
 380 }
 381
 382 static void gadget_info_attr_release(struct config_item *item)
 383 {
 384         struct gadget_info *gi = to_gadget_info(item);
 385
 386         WARN_ON(!list_empty(&gi->cdev.configs));
 387         WARN_ON(!list_empty(&gi->string_list));
 388         WARN_ON(!list_empty(&gi->available_func));
 389         kfree(gi->composite.gadget_driver.function);
 390         kfree(gi);
 391 }
 392
 393 static struct configfs_item_operations gadget_root_item_ops = {
 394         .release                = gadget_info_attr_release,
 395 };
 396
 397 static void gadget_config_attr_release(struct config_item *item)
 398 {
 399         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
 400
 401         WARN_ON(!list_empty(&cfg->c.functions));
 402         list_del(&cfg->c.list);
 403         kfree(cfg->c.label);
 404         kfree(cfg);
 405 }
 406
 407 static int config_usb_cfg_link(
 408         struct config_item *usb_cfg_ci,
 409         struct config_item *usb_func_ci)
 410 {
 411         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
 412         struct usb_composite_dev *cdev = cfg->c.cdev;
 413         struct gadget_info *gi = container_of(cdev, struct gadget_info, cdev);
 414
 415         struct config_group *group = to_config_group(usb_func_ci);
 416         struct usb_function_instance *fi = container_of(group,
 417                         struct usb_function_instance, group);
 418         struct usb_function_instance *a_fi;
 419         struct usb_function *f;
 420         int ret;
 421
 422         mutex_lock(&gi->lock);
 423         /*
 424          * Make sure this function is from within our _this_ gadget and not
 425          * from another gadget or a random directory.
 426          * Also a function instance can only be linked once.
 427          */
 428         list_for_each_entry(a_fi, &gi->available_func, cfs_list) {
 429                 if (a_fi == fi)
 430                         break;
 431         }
 432         if (a_fi != fi) {
 433                 ret = -EINVAL;
 434                 goto out;
 435         }
 436
 437         list_for_each_entry(f, &cfg->func_list, list) {
 438                 if (f->fi == fi) {
 439                         ret = -EEXIST;
 440                         goto out;
 441                 }
 442         }
 443
 444         f = usb_get_function(fi);
 445         if (IS_ERR(f)) {
 446                 ret = PTR_ERR(f);
 447                 goto out;
 448         }
 449
 450         /* stash the function until we bind it to the gadget */
 451         list_add_tail(&f->list, &cfg->func_list);
 452         ret = 0;
 453 out:
 454         mutex_unlock(&gi->lock);
 455         return ret;
 456 }
 457
 458 static void config_usb_cfg_unlink(
 459         struct config_item *usb_cfg_ci,
 460         struct config_item *usb_func_ci)
 461 {
 462         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
 463         struct usb_composite_dev *cdev = cfg->c.cdev;
 464         struct gadget_info *gi = container_of(cdev, struct gadget_info, cdev);
 465
 466         struct config_group *group = to_config_group(usb_func_ci);
 467         struct usb_function_instance *fi = container_of(group,
 468                         struct usb_function_instance, group);
 469         struct usb_function *f;
 470
 471         /*
 472          * ideally I would like to forbid to unlink functions while a gadget is
 473          * bound to an UDC. Since this isn't possible at the moment, we simply
 474          * force an unbind, the function is available here and then we can
 475          * remove the function.
 476          */
 477         mutex_lock(&gi->lock);
 478         if (gi->composite.gadget_driver.udc_name)
 479                 unregister_gadget(gi);
 480         WARN_ON(gi->composite.gadget_driver.udc_name);
 481
 482         list_for_each_entry(f, &cfg->func_list, list) {
 483                 if (f->fi == fi) {
 484                         list_del(&f->list);
 485                         usb_put_function(f);
 486                         mutex_unlock(&gi->lock);
 487                         return;
 488                 }
 489         }
 490         mutex_unlock(&gi->lock);
 491         WARN(1, "Unable to locate function to unbind\n");
 492 }
 493
 494 static struct configfs_item_operations gadget_config_item_ops = {
 495         .release                = gadget_config_attr_release,
 496         .allow_link             = config_usb_cfg_link,
 497         .drop_link              = config_usb_cfg_unlink,
 498 };
 499
 500
 501 static ssize_t gadget_config_desc_MaxPower_show(struct config_item *item,
 502                 char *page)
 503 {
 504         return sprintf(page, "%u\n", to_config_usb_cfg(item)->c.MaxPower);
 505 }
 506
 507 static ssize_t gadget_config_desc_MaxPower_store(struct config_item *item,
 508                 const char *page, size_t len)
 509 {
 510         u16 val;
 511         int ret;
 512         ret = kstrtou16(page, 0, &val);
 513         if (ret)
 514                 return ret;
 515         if (DIV_ROUND_UP(val, 8) > 0xff)
 516                 return -ERANGE;
 517         to_config_usb_cfg(item)->c.MaxPower = val;
 518         return len;
 519 }
 520
 521 static ssize_t gadget_config_desc_bmAttributes_show(struct config_item *item,
 522                 char *page)
 523 {
 524         return sprintf(page, "0x%02x\n",
 525                 to_config_usb_cfg(item)->c.bmAttributes);
 526 }
 527
 528 static ssize_t gadget_config_desc_bmAttributes_store(struct config_item *item,
 529                 const char *page, size_t len)
 530 {
 531         u8 val;
 532         int ret;
 533         ret = kstrtou8(page, 0, &val);
 534         if (ret)
 535                 return ret;
 536         if (!(val & USB_CONFIG_ATT_ONE))
 537                 return -EINVAL;
 538         if (val & ~(USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER |
 539                                 USB_CONFIG_ATT_WAKEUP))
 540                 return -EINVAL;
 541         to_config_usb_cfg(item)->c.bmAttributes = val;
 542         return len;
 543 }
 544
 545 CONFIGFS_ATTR(gadget_config_desc_, MaxPower);
 546 CONFIGFS_ATTR(gadget_config_desc_, bmAttributes);
 547
 548 static struct configfs_attribute *gadget_config_attrs[] = {
 549         &gadget_config_desc_attr_MaxPower,
 550         &gadget_config_desc_attr_bmAttributes,
 551         NULL,
 552 };
 553
 554 static const struct config_item_type gadget_config_type = {
 555         .ct_item_ops    = &gadget_config_item_ops,
 556         .ct_attrs       = gadget_config_attrs,
 557         .ct_owner       = THIS_MODULE,
 558 };
 559
 560 static const struct config_item_type gadget_root_type = {
 561         .ct_item_ops    = &gadget_root_item_ops,
 562         .ct_attrs       = gadget_root_attrs,
 563         .ct_owner       = THIS_MODULE,
 564 };
 565
 566 static void composite_init_dev(struct usb_composite_dev *cdev)
 567 {
 568         spin_lock_init(&cdev->lock);
 569         INIT_LIST_HEAD(&cdev->configs);
 570         INIT_LIST_HEAD(&cdev->gstrings);
 571 }
 572
 573 static struct config_group *function_make(
 574                 struct config_group *group,
 575                 const char *name)
 576 {
 577         struct gadget_info *gi;
 578         struct usb_function_instance *fi;
 579         char buf[MAX_NAME_LEN];
 580         char *func_name;
 581         char *instance_name;
 582         int ret;
 583
 584         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
 585         if (ret >= MAX_NAME_LEN)
 586                 return ERR_PTR(-ENAMETOOLONG);
 587
 588         func_name = buf;
 589         instance_name = strchr(func_name, '.');
 590         if (!instance_name) {
 591                 pr_err("Unable to locate . in FUNC.INSTANCE\n");
 592                 return ERR_PTR(-EINVAL);
 593         }
 594         *instance_name = '\0';
 595         instance_name++;
 596
 597         fi = usb_get_function_instance(func_name);
 598         if (IS_ERR(fi))
 599                 return ERR_CAST(fi);
 600
 601         ret = config_item_set_name(&fi->group.cg_item, "%s", name);
 602         if (ret) {
 603                 usb_put_function_instance(fi);
 604                 return ERR_PTR(ret);
 605         }
 606         if (fi->set_inst_name) {
 607                 ret = fi->set_inst_name(fi, instance_name);
 608                 if (ret) {
 609                         usb_put_function_instance(fi);
 610                         return ERR_PTR(ret);
 611                 }
 612         }
 613
 614         gi = container_of(group, struct gadget_info, functions_group);
 615
 616         mutex_lock(&gi->lock);
 617         list_add_tail(&fi->cfs_list, &gi->available_func);
 618         mutex_unlock(&gi->lock);
 619         return &fi->group;
 620 }
 621
 622 static void function_drop(
 623                 struct config_group *group,
 624                 struct config_item *item)
 625 {
 626         struct usb_function_instance *fi = to_usb_function_instance(item);
 627         struct gadget_info *gi;
 628
 629         gi = container_of(group, struct gadget_info, functions_group);
 630
 631         mutex_lock(&gi->lock);
 632         list_del(&fi->cfs_list);
 633         mutex_unlock(&gi->lock);
 634         config_item_put(item);
 635 }
 636
 637 static struct configfs_group_operations functions_ops = {
 638         .make_group     = &function_make,
 639         .drop_item      = &function_drop,
 640 };
 641
 642 static const struct config_item_type functions_type = {
 643         .ct_group_ops   = &functions_ops,
 644         .ct_owner       = THIS_MODULE,
 645 };
 646
 647 GS_STRINGS_RW(gadget_config_name, configuration);
 648
 649 static struct configfs_attribute *gadget_config_name_langid_attrs[] = {
 650         &gadget_config_name_attr_configuration,
 651         NULL,
 652 };
 653
 654 static void gadget_config_name_attr_release(struct config_item *item)
 655 {
 656         struct gadget_config_name *cn = to_gadget_config_name(item);
 657
 658         kfree(cn->configuration);
 659
 660         list_del(&cn->list);
 661         kfree(cn);
 662 }
 663
 664 USB_CONFIG_STRING_RW_OPS(gadget_config_name);
 665 USB_CONFIG_STRINGS_LANG(gadget_config_name, config_usb_cfg);
 666
 667 static struct config_group *config_desc_make(
 668                 struct config_group *group,
 669                 const char *name)
 670 {
 671         struct gadget_info *gi;
 672         struct config_usb_cfg *cfg;
 673         char buf[MAX_NAME_LEN];
 674         char *num_str;
 675         u8 num;
 676         int ret;
 677
 678         gi = container_of(group, struct gadget_info, configs_group);
 679         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
 680         if (ret >= MAX_NAME_LEN)
 681                 return ERR_PTR(-ENAMETOOLONG);
 682
 683         num_str = strchr(buf, '.');
 684         if (!num_str) {
 685                 pr_err("Unable to locate . in name.bConfigurationValue\n");
 686                 return ERR_PTR(-EINVAL);
 687         }
 688
 689         *num_str = '\0';
 690         num_str++;
 691
 692         if (!strlen(buf))
 693                 return ERR_PTR(-EINVAL);
 694
 695         ret = kstrtou8(num_str, 0, &num);
 696         if (ret)
 697                 return ERR_PTR(ret);
 698
 699         cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
 700         if (!cfg)
 701                 return ERR_PTR(-ENOMEM);
 702         cfg->c.label = kstrdup(buf, GFP_KERNEL);
 703         if (!cfg->c.label) {
 704                 ret = -ENOMEM;
 705                 goto err;
 706         }
 707         cfg->c.bConfigurationValue = num;
 708         cfg->c.MaxPower = CONFIG_USB_GADGET_VBUS_DRAW;
 709         cfg->c.bmAttributes = USB_CONFIG_ATT_ONE;
 710         INIT_LIST_HEAD(&cfg->string_list);
 711         INIT_LIST_HEAD(&cfg->func_list);
 712
 713         config_group_init_type_name(&cfg->group, name,
 714                                 &gadget_config_type);
 715
 716         config_group_init_type_name(&cfg->strings_group, "strings",
 717                         &gadget_config_name_strings_type);
 718         configfs_add_default_group(&cfg->strings_group, &cfg->group);
 719
 720         ret = usb_add_config_only(&gi->cdev, &cfg->c);
 721         if (ret)
 722                 goto err;
 723
 724         return &cfg->group;
 725 err:
 726         kfree(cfg->c.label);
 727         kfree(cfg);
 728         return ERR_PTR(ret);
 729 }
 730
 731 static void config_desc_drop(
 732                 struct config_group *group,
 733                 struct config_item *item)
 734 {
 735         config_item_put(item);
 736 }
 737
 738 static struct configfs_group_operations config_desc_ops = {
 739         .make_group     = &config_desc_make,
 740         .drop_item      = &config_desc_drop,
 741 };
 742
 743 static const struct config_item_type config_desc_type = {
 744         .ct_group_ops   = &config_desc_ops,
 745         .ct_owner       = THIS_MODULE,
 746 };
 747
 748 GS_STRINGS_RW(gadget_strings, manufacturer);
 749 GS_STRINGS_RW(gadget_strings, product);
 750 GS_STRINGS_RW(gadget_strings, serialnumber);
 751
 752 static struct configfs_attribute *gadget_strings_langid_attrs[] = {
 753         &gadget_strings_attr_manufacturer,
 754         &gadget_strings_attr_product,
 755         &gadget_strings_attr_serialnumber,
 756         NULL,
 757 };
 758
 759 static void gadget_strings_attr_release(struct config_item *item)
 760 {
 761         struct gadget_strings *gs = to_gadget_strings(item);
 762
 763         kfree(gs->manufacturer);
 764         kfree(gs->product);
 765         kfree(gs->serialnumber);
 766
 767         list_del(&gs->list);
 768         kfree(gs);
 769 }
 770
 771 USB_CONFIG_STRING_RW_OPS(gadget_strings);
 772 USB_CONFIG_STRINGS_LANG(gadget_strings, gadget_info);
 773
 774 static inline struct os_desc *to_os_desc(struct config_item *item)
 775 {
 776         return container_of(to_config_group(item), struct os_desc, group);
 777 }
 778
 779 static inline struct gadget_info *os_desc_item_to_gadget_info(
 780                 struct config_item *item)
 781 {
 782         return to_gadget_info(to_os_desc(item)->group.cg_item.ci_parent);
 783 }
 784
 785 static ssize_t os_desc_use_show(struct config_item *item, char *page)
 786 {
 787         return sprintf(page, "%d\n",
 788                         os_desc_item_to_gadget_info(item)->use_os_desc);
 789 }
 790
 791 static ssize_t os_desc_use_store(struct config_item *item, const char *page,
 792                                  size_t len)
 793 {
 794         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 795         int ret;
 796         bool use;
 797
 798         mutex_lock(&gi->lock);
 799         ret = strtobool(page, &use);
 800         if (!ret) {
 801                 gi->use_os_desc = use;
 802                 ret = len;
 803         }
 804         mutex_unlock(&gi->lock);
 805
 806         return ret;
 807 }
 808
 809 static ssize_t os_desc_b_vendor_code_show(struct config_item *item, char *page)
 810 {
 811         return sprintf(page, "0x%02x\n",
 812                         os_desc_item_to_gadget_info(item)->b_vendor_code);
 813 }
 814
 815 static ssize_t os_desc_b_vendor_code_store(struct config_item *item,
 816                                            const char *page, size_t len)
 817 {
 818         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 819         int ret;
 820         u8 b_vendor_code;
 821
 822         mutex_lock(&gi->lock);
 823         ret = kstrtou8(page, 0, &b_vendor_code);
 824         if (!ret) {
 825                 gi->b_vendor_code = b_vendor_code;
 826                 ret = len;
 827         }
 828         mutex_unlock(&gi->lock);
 829
 830         return ret;
 831 }
 832
 833 static ssize_t os_desc_qw_sign_show(struct config_item *item, char *page)
 834 {
 835         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 836         int res;
 837
 838         res = utf16s_to_utf8s((wchar_t *) gi->qw_sign, OS_STRING_QW_SIGN_LEN,
 839                               UTF16_LITTLE_ENDIAN, page, PAGE_SIZE - 1);
 840         page[res++] = '\n';
 841
 842         return res;
 843 }
 844
 845 static ssize_t os_desc_qw_sign_store(struct config_item *item, const char *page,
 846                                      size_t len)
 847 {
 848         struct gadget_info *gi = os_desc_item_to_gadget_info(item);
 849         int res, l;
 850
 851         l = min((int)len, OS_STRING_QW_SIGN_LEN >> 1);
 852         if (page[l - 1] == '\n')
 853                 --l;
 854
 855         mutex_lock(&gi->lock);
 856         res = utf8s_to_utf16s(page, l,
 857                               UTF16_LITTLE_ENDIAN, (wchar_t *) gi->qw_sign,
 858                               OS_STRING_QW_SIGN_LEN);
 859         if (res > 0)
 860                 res = len;
 861         mutex_unlock(&gi->lock);
 862
 863         return res;
 864 }
 865
 866 CONFIGFS_ATTR(os_desc_, use);
 867 CONFIGFS_ATTR(os_desc_, b_vendor_code);
 868 CONFIGFS_ATTR(os_desc_, qw_sign);
 869
 870 static struct configfs_attribute *os_desc_attrs[] = {
 871         &os_desc_attr_use,
 872         &os_desc_attr_b_vendor_code,
 873         &os_desc_attr_qw_sign,
 874         NULL,
 875 };
 876
 877 static void os_desc_attr_release(struct config_item *item)
 878 {
 879         struct os_desc *os_desc = to_os_desc(item);
 880         kfree(os_desc);
 881 }
 882
 883 static int os_desc_link(struct config_item *os_desc_ci,
 884                         struct config_item *usb_cfg_ci)
 885 {
 886         struct gadget_info *gi = container_of(to_config_group(os_desc_ci),
 887                                         struct gadget_info, os_desc_group);
 888         struct usb_composite_dev *cdev = &gi->cdev;
 889         struct config_usb_cfg *c_target =
 890                 container_of(to_config_group(usb_cfg_ci),
 891                              struct config_usb_cfg, group);
 892         struct usb_configuration *c;
 893         int ret;
 894
 895         mutex_lock(&gi->lock);
 896         list_for_each_entry(c, &cdev->configs, list) {
 897                 if (c == &c_target->c)
 898                         break;
 899         }
 900         if (c != &c_target->c) {
 901                 ret = -EINVAL;
 902                 goto out;
 903         }
 904
 905         if (cdev->os_desc_config) {
 906                 ret = -EBUSY;
 907                 goto out;
 908         }
 909
 910         cdev->os_desc_config = &c_target->c;
 911         ret = 0;
 912
 913 out:
 914         mutex_unlock(&gi->lock);
 915         return ret;
 916 }
 917
 918 static void os_desc_unlink(struct config_item *os_desc_ci,
 919                           struct config_item *usb_cfg_ci)
 920 {
 921         struct gadget_info *gi = container_of(to_config_group(os_desc_ci),
 922                                         struct gadget_info, os_desc_group);
 923         struct usb_composite_dev *cdev = &gi->cdev;
 924
 925         mutex_lock(&gi->lock);
 926         if (gi->composite.gadget_driver.udc_name)
 927                 unregister_gadget(gi);
 928         cdev->os_desc_config = NULL;
 929         WARN_ON(gi->composite.gadget_driver.udc_name);
 930         mutex_unlock(&gi->lock);
 931 }
 932
 933 static struct configfs_item_operations os_desc_ops = {
 934         .release                = os_desc_attr_release,
 935         .allow_link             = os_desc_link,
 936         .drop_link              = os_desc_unlink,
 937 };
 938
 939 static struct config_item_type os_desc_type = {
 940         .ct_item_ops    = &os_desc_ops,
 941         .ct_attrs       = os_desc_attrs,
 942         .ct_owner       = THIS_MODULE,
 943 };
 944
 945 static inline struct usb_os_desc_ext_prop
 946 *to_usb_os_desc_ext_prop(struct config_item *item)
 947 {
 948         return container_of(item, struct usb_os_desc_ext_prop, item);
 949 }
 950
 951 static ssize_t ext_prop_type_show(struct config_item *item, char *page)
 952 {
 953         return sprintf(page, "%d\n", to_usb_os_desc_ext_prop(item)->type);
 954 }
 955
 956 static ssize_t ext_prop_type_store(struct config_item *item,
 957                                    const char *page, size_t len)
 958 {
 959         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
 960         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
 961         u8 type;
 962         int ret;
 963
 964         if (desc->opts_mutex)
 965                 mutex_lock(desc->opts_mutex);
 966         ret = kstrtou8(page, 0, &type);
 967         if (ret)
 968                 goto end;
 969         if (type < USB_EXT_PROP_UNICODE || type > USB_EXT_PROP_UNICODE_MULTI) {
 970                 ret = -EINVAL;
 971                 goto end;
 972         }
 973
 974         if ((ext_prop->type == USB_EXT_PROP_BINARY ||
 975             ext_prop->type == USB_EXT_PROP_LE32 ||
 976             ext_prop->type == USB_EXT_PROP_BE32) &&
 977             (type == USB_EXT_PROP_UNICODE ||
 978             type == USB_EXT_PROP_UNICODE_ENV ||
 979             type == USB_EXT_PROP_UNICODE_LINK))
 980                 ext_prop->data_len <<= 1;
 981         else if ((ext_prop->type == USB_EXT_PROP_UNICODE ||
 982                    ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
 983                    ext_prop->type == USB_EXT_PROP_UNICODE_LINK) &&
 984                    (type == USB_EXT_PROP_BINARY ||
 985                    type == USB_EXT_PROP_LE32 ||
 986                    type == USB_EXT_PROP_BE32))
 987                 ext_prop->data_len >>= 1;
 988         ext_prop->type = type;
 989         ret = len;
 990
 991 end:
 992         if (desc->opts_mutex)
 993                 mutex_unlock(desc->opts_mutex);
 994         return ret;
 995 }
 996
 997 static ssize_t ext_prop_data_show(struct config_item *item, char *page)
 998 {
 999         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1000         int len = ext_prop->data_len;
1001
1002         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
1003             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
1004             ext_prop->type == USB_EXT_PROP_UNICODE_LINK)
1005                 len >>= 1;
1006         memcpy(page, ext_prop->data, len);
1007
1008         return len;
1009 }
1010
1011 static ssize_t ext_prop_data_store(struct config_item *item,
1012                                    const char *page, size_t len)
1013 {
1014         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1015         struct usb_os_desc *desc = to_usb_os_desc(ext_prop->item.ci_parent);
1016         char *new_data;
1017         size_t ret_len = len;
1018
1019         if (page[len - 1] == '\n' || page[len - 1] == '\0')
1020                 --len;
1021         new_data = kmemdup(page, len, GFP_KERNEL);
1022         if (!new_data)
1023                 return -ENOMEM;
1024
1025         if (desc->opts_mutex)
1026                 mutex_lock(desc->opts_mutex);
1027         kfree(ext_prop->data);
1028         ext_prop->data = new_data;
1029         desc->ext_prop_len -= ext_prop->data_len;
1030         ext_prop->data_len = len;
1031         desc->ext_prop_len += ext_prop->data_len;
1032         if (ext_prop->type == USB_EXT_PROP_UNICODE ||
1033             ext_prop->type == USB_EXT_PROP_UNICODE_ENV ||
1034             ext_prop->type == USB_EXT_PROP_UNICODE_LINK) {
1035                 desc->ext_prop_len -= ext_prop->data_len;
1036                 ext_prop->data_len <<= 1;
1037                 ext_prop->data_len += 2;
1038                 desc->ext_prop_len += ext_prop->data_len;
1039         }
1040         if (desc->opts_mutex)
1041                 mutex_unlock(desc->opts_mutex);
1042         return ret_len;
1043 }
1044
1045 CONFIGFS_ATTR(ext_prop_, type);
1046 CONFIGFS_ATTR(ext_prop_, data);
1047
1048 static struct configfs_attribute *ext_prop_attrs[] = {
1049         &ext_prop_attr_type,
1050         &ext_prop_attr_data,
1051         NULL,
1052 };
1053
1054 static void usb_os_desc_ext_prop_release(struct config_item *item)
1055 {
1056         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1057
1058         kfree(ext_prop); /* frees a whole chunk */
1059 }
1060
1061 static struct configfs_item_operations ext_prop_ops = {
1062         .release                = usb_os_desc_ext_prop_release,
1063 };
1064
1065 static struct config_item *ext_prop_make(
1066                 struct config_group *group,
1067                 const char *name)
1068 {
1069         struct usb_os_desc_ext_prop *ext_prop;
1070         struct config_item_type *ext_prop_type;
1071         struct usb_os_desc *desc;
1072         char *vlabuf;
1073
1074         vla_group(data_chunk);
1075         vla_item(data_chunk, struct usb_os_desc_ext_prop, ext_prop, 1);
1076         vla_item(data_chunk, struct config_item_type, ext_prop_type, 1);
1077
1078         vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1079         if (!vlabuf)
1080                 return ERR_PTR(-ENOMEM);
1081
1082         ext_prop = vla_ptr(vlabuf, data_chunk, ext_prop);
1083         ext_prop_type = vla_ptr(vlabuf, data_chunk, ext_prop_type);
1084
1085         desc = container_of(group, struct usb_os_desc, group);
1086         ext_prop_type->ct_item_ops = &ext_prop_ops;
1087         ext_prop_type->ct_attrs = ext_prop_attrs;
1088         ext_prop_type->ct_owner = desc->owner;
1089
1090         config_item_init_type_name(&ext_prop->item, name, ext_prop_type);
1091
1092         ext_prop->name = kstrdup(name, GFP_KERNEL);
1093         if (!ext_prop->name) {
1094                 kfree(vlabuf);
1095                 return ERR_PTR(-ENOMEM);
1096         }
1097         desc->ext_prop_len += 14;
1098         ext_prop->name_len = 2 * strlen(ext_prop->name) + 2;
1099         if (desc->opts_mutex)
1100                 mutex_lock(desc->opts_mutex);
1101         desc->ext_prop_len += ext_prop->name_len;
1102         list_add_tail(&ext_prop->entry, &desc->ext_prop);
1103         ++desc->ext_prop_count;
1104         if (desc->opts_mutex)
1105                 mutex_unlock(desc->opts_mutex);
1106
1107         return &ext_prop->item;
1108 }
1109
1110 static void ext_prop_drop(struct config_group *group, struct config_item *item)
1111 {
1112         struct usb_os_desc_ext_prop *ext_prop = to_usb_os_desc_ext_prop(item);
1113         struct usb_os_desc *desc = to_usb_os_desc(&group->cg_item);
1114
1115         if (desc->opts_mutex)
1116                 mutex_lock(desc->opts_mutex);
1117         list_del(&ext_prop->entry);
1118         --desc->ext_prop_count;
1119         kfree(ext_prop->name);
1120         desc->ext_prop_len -= (ext_prop->name_len + ext_prop->data_len + 14);
1121         if (desc->opts_mutex)
1122                 mutex_unlock(desc->opts_mutex);
1123         config_item_put(item);
1124 }
1125
1126 static struct configfs_group_operations interf_grp_ops = {
1127         .make_item      = &ext_prop_make,
1128         .drop_item      = &ext_prop_drop,
1129 };
1130
1131 static ssize_t interf_grp_compatible_id_show(struct config_item *item,
1132                                              char *page)
1133 {
1134         memcpy(page, to_usb_os_desc(item)->ext_compat_id, 8);
1135         return 8;
1136 }
1137
1138 static ssize_t interf_grp_compatible_id_store(struct config_item *item,
1139                                               const char *page, size_t len)
1140 {
1141         struct usb_os_desc *desc = to_usb_os_desc(item);
1142         int l;
1143
1144         l = min_t(int, 8, len);
1145         if (page[l - 1] == '\n')
1146                 --l;
1147         if (desc->opts_mutex)
1148                 mutex_lock(desc->opts_mutex);
1149         memcpy(desc->ext_compat_id, page, l);
1150
1151         if (desc->opts_mutex)
1152                 mutex_unlock(desc->opts_mutex);
1153
1154         return len;
1155 }
1156
1157 static ssize_t interf_grp_sub_compatible_id_show(struct config_item *item,
1158                                                  char *page)
1159 {
1160         memcpy(page, to_usb_os_desc(item)->ext_compat_id + 8, 8);
1161         return 8;
1162 }
1163
1164 static ssize_t interf_grp_sub_compatible_id_store(struct config_item *item,
1165                                                   const char *page, size_t len)
1166 {
1167         struct usb_os_desc *desc = to_usb_os_desc(item);
1168         int l;
1169
1170         l = min_t(int, 8, len);
1171         if (page[l - 1] == '\n')
1172                 --l;
1173         if (desc->opts_mutex)
1174                 mutex_lock(desc->opts_mutex);
1175         memcpy(desc->ext_compat_id + 8, page, l);
1176
1177         if (desc->opts_mutex)
1178                 mutex_unlock(desc->opts_mutex);
1179
1180         return len;
1181 }
1182
1183 CONFIGFS_ATTR(interf_grp_, compatible_id);
1184 CONFIGFS_ATTR(interf_grp_, sub_compatible_id);
1185
1186 static struct configfs_attribute *interf_grp_attrs[] = {
1187         &interf_grp_attr_compatible_id,
1188         &interf_grp_attr_sub_compatible_id,
1189         NULL
1190 };
1191
1192 struct config_group *usb_os_desc_prepare_interf_dir(
1193                 struct config_group *parent,
1194                 int n_interf,
1195                 struct usb_os_desc **desc,
1196                 char **names,
1197                 struct module *owner)
1198 {
1199         struct config_group *os_desc_group;
1200         struct config_item_type *os_desc_type, *interface_type;
1201
1202         vla_group(data_chunk);
1203         vla_item(data_chunk, struct config_group, os_desc_group, 1);
1204         vla_item(data_chunk, struct config_item_type, os_desc_type, 1);
1205         vla_item(data_chunk, struct config_item_type, interface_type, 1);
1206
1207         char *vlabuf = kzalloc(vla_group_size(data_chunk), GFP_KERNEL);
1208         if (!vlabuf)
1209                 return ERR_PTR(-ENOMEM);
1210
1211         os_desc_group = vla_ptr(vlabuf, data_chunk, os_desc_group);
1212         os_desc_type = vla_ptr(vlabuf, data_chunk, os_desc_type);
1213         interface_type = vla_ptr(vlabuf, data_chunk, interface_type);
1214
1215         os_desc_type->ct_owner = owner;
1216         config_group_init_type_name(os_desc_group, "os_desc", os_desc_type);
1217         configfs_add_default_group(os_desc_group, parent);
1218
1219         interface_type->ct_group_ops = &interf_grp_ops;
1220         interface_type->ct_attrs = interf_grp_attrs;
1221         interface_type->ct_owner = owner;
1222
1223         while (n_interf--) {
1224                 struct usb_os_desc *d;
1225
1226                 d = desc[n_interf];
1227                 d->owner = owner;
1228                 config_group_init_type_name(&d->group, "", interface_type);
1229                 config_item_set_name(&d->group.cg_item, "interface.%s",
1230                                      names[n_interf]);
1231                 configfs_add_default_group(&d->group, os_desc_group);
1232         }
1233
1234         return os_desc_group;
1235 }
1236 EXPORT_SYMBOL(usb_os_desc_prepare_interf_dir);
1237
1238 static int configfs_do_nothing(struct usb_composite_dev *cdev)
1239 {
1240         WARN_ON(1);
1241         return -EINVAL;
1242 }
1243
1244 int composite_dev_prepare(struct usb_composite_driver *composite,
1245                 struct usb_composite_dev *dev);
1246
1247 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
1248                                   struct usb_ep *ep0);
1249
1250 static void purge_configs_funcs(struct gadget_info *gi)
1251 {
1252         struct usb_configuration        *c;
1253
1254         list_for_each_entry(c, &gi->cdev.configs, list) {
1255                 struct usb_function *f, *tmp;
1256                 struct config_usb_cfg *cfg;
1257
1258                 cfg = container_of(c, struct config_usb_cfg, c);
1259
1260                 list_for_each_entry_safe(f, tmp, &c->functions, list) {
1261
1262                         list_move_tail(&f->list, &cfg->func_list);
1263                         if (f->unbind) {
1264                                 dev_dbg(&gi->cdev.gadget->dev,
1265                                         "unbind function '%s'/%p\n",
1266                                         f->name, f);
1267                                 f->unbind(c, f);
1268                         }
1269                 }
1270                 c->next_interface_id = 0;
1271                 memset(c->interface, 0, sizeof(c->interface));
1272                 c->superspeed_plus = 0;
1273                 c->superspeed = 0;
1274                 c->highspeed = 0;
1275                 c->fullspeed = 0;
1276         }
1277 }
1278
1279 static int configfs_composite_bind(struct usb_gadget *gadget,
1280                 struct usb_gadget_driver *gdriver)
1281 {
1282         struct usb_composite_driver     *composite = to_cdriver(gdriver);
1283         struct gadget_info              *gi = container_of(composite,
1284                                                 struct gadget_info, composite);
1285         struct usb_composite_dev        *cdev = &gi->cdev;
1286         struct usb_configuration        *c;
1287         struct usb_string               *s;
1288         unsigned                        i;
1289         int                             ret;
1290
1291         /* the gi->lock is hold by the caller */
1292         gi->unbind = 0;
1293         cdev->gadget = gadget;
1294         set_gadget_data(gadget, cdev);
1295         ret = composite_dev_prepare(composite, cdev);
1296         if (ret)
1297                 return ret;
1298         /* and now the gadget bind */
1299         ret = -EINVAL;
1300
1301         if (list_empty(&gi->cdev.configs)) {
1302                 pr_err("Need at least one configuration in %s.\n",
1303                                 gi->composite.name);
1304                 goto err_comp_cleanup;
1305         }
1306
1307
1308         list_for_each_entry(c, &gi->cdev.configs, list) {
1309                 struct config_usb_cfg *cfg;
1310
1311                 cfg = container_of(c, struct config_usb_cfg, c);
1312                 if (list_empty(&cfg->func_list)) {
1313                         pr_err("Config %s/%d of %s needs at least one function.\n",
1314                               c->label, c->bConfigurationValue,
1315                               gi->composite.name);
1316                         goto err_comp_cleanup;
1317                 }
1318         }
1319
1320         /* init all strings */
1321         if (!list_empty(&gi->string_list)) {
1322                 struct gadget_strings *gs;
1323
1324                 i = 0;
1325                 list_for_each_entry(gs, &gi->string_list, list) {
1326
1327                         gi->gstrings[i] = &gs->stringtab_dev;
1328                         gs->stringtab_dev.strings = gs->strings;
1329                         gs->strings[USB_GADGET_MANUFACTURER_IDX].s =
1330                                 gs->manufacturer;
1331                         gs->strings[USB_GADGET_PRODUCT_IDX].s = gs->product;
1332                         gs->strings[USB_GADGET_SERIAL_IDX].s = gs->serialnumber;
1333                         i++;
1334                 }
1335                 gi->gstrings[i] = NULL;
1336                 s = usb_gstrings_attach(&gi->cdev, gi->gstrings,
1337                                 USB_GADGET_FIRST_AVAIL_IDX);
1338                 if (IS_ERR(s)) {
1339                         ret = PTR_ERR(s);
1340                         goto err_comp_cleanup;
1341                 }
1342
1343                 gi->cdev.desc.iManufacturer = s[USB_GADGET_MANUFACTURER_IDX].id;
1344                 gi->cdev.desc.iProduct = s[USB_GADGET_PRODUCT_IDX].id;
1345                 gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
1346         }
1347
1348         if (gi->use_os_desc) {
1349                 cdev->use_os_string = true;
1350                 cdev->b_vendor_code = gi->b_vendor_code;
1351                 memcpy(cdev->qw_sign, gi->qw_sign, OS_STRING_QW_SIGN_LEN);
1352         }
1353
1354         if (gadget_is_otg(gadget) && !otg_desc[0]) {
1355                 struct usb_descriptor_header *usb_desc;
1356
1357                 usb_desc = usb_otg_descriptor_alloc(gadget);
1358                 if (!usb_desc) {
1359                         ret = -ENOMEM;
1360                         goto err_comp_cleanup;
1361                 }
1362                 usb_otg_descriptor_init(gadget, usb_desc);
1363                 otg_desc[0] = usb_desc;
1364                 otg_desc[1] = NULL;
1365         }
1366
1367         /* Go through all configs, attach all functions */
1368         list_for_each_entry(c, &gi->cdev.configs, list) {
1369                 struct config_usb_cfg *cfg;
1370                 struct usb_function *f;
1371                 struct usb_function *tmp;
1372                 struct gadget_config_name *cn;
1373
1374                 if (gadget_is_otg(gadget))
1375                         c->descriptors = otg_desc;
1376
1377                 cfg = container_of(c, struct config_usb_cfg, c);
1378                 if (!list_empty(&cfg->string_list)) {
1379                         i = 0;
1380                         list_for_each_entry(cn, &cfg->string_list, list) {
1381                                 cfg->gstrings[i] = &cn->stringtab_dev;
1382                                 cn->stringtab_dev.strings = &cn->strings;
1383                                 cn->strings.s = cn->configuration;
1384                                 i++;
1385                         }
1386                         cfg->gstrings[i] = NULL;
1387                         s = usb_gstrings_attach(&gi->cdev, cfg->gstrings, 1);
1388                         if (IS_ERR(s)) {
1389                                 ret = PTR_ERR(s);
1390                                 goto err_comp_cleanup;
1391                         }
1392                         c->iConfiguration = s[0].id;
1393                 }
1394
1395                 list_for_each_entry_safe(f, tmp, &cfg->func_list, list) {
1396                         list_del(&f->list);
1397                         ret = usb_add_function(c, f);
1398                         if (ret) {
1399                                 list_add(&f->list, &cfg->func_list);
1400                                 goto err_purge_funcs;
1401                         }
1402                 }
1403                 usb_ep_autoconfig_reset(cdev->gadget);
1404         }
1405         if (cdev->use_os_string) {
1406                 ret = composite_os_desc_req_prepare(cdev, gadget->ep0);
1407                 if (ret)
1408                         goto err_purge_funcs;
1409         }
1410
1411         usb_ep_autoconfig_reset(cdev->gadget);
1412         return 0;
1413
1414 err_purge_funcs:
1415         purge_configs_funcs(gi);
1416 err_comp_cleanup:
1417         composite_dev_cleanup(cdev);
1418         return ret;
1419 }
1420
1421 static void configfs_composite_unbind(struct usb_gadget *gadget)
1422 {
1423         struct usb_composite_dev        *cdev;
1424         struct gadget_info              *gi;
1425         unsigned long flags;
1426
1427         /* the gi->lock is hold by the caller */
1428
1429         cdev = get_gadget_data(gadget);
1430         gi = container_of(cdev, struct gadget_info, cdev);
1431         spin_lock_irqsave(&gi->spinlock, flags);
1432         gi->unbind = 1;
1433         spin_unlock_irqrestore(&gi->spinlock, flags);
1434
1435         kfree(otg_desc[0]);
1436         otg_desc[0] = NULL;
1437         purge_configs_funcs(gi);
1438         composite_dev_cleanup(cdev);
1439         usb_ep_autoconfig_reset(cdev->gadget);
1440         spin_lock_irqsave(&gi->spinlock, flags);
1441         cdev->gadget = NULL;
1442         set_gadget_data(gadget, NULL);
1443         spin_unlock_irqrestore(&gi->spinlock, flags);
1444 }
1445
1446 static int configfs_composite_setup(struct usb_gadget *gadget,
1447                 const struct usb_ctrlrequest *ctrl)
1448 {
1449         struct usb_composite_dev *cdev;
1450         struct gadget_info *gi;
1451         unsigned long flags;
1452         int ret;
1453
1454         cdev = get_gadget_data(gadget);
1455         if (!cdev)
1456                 return 0;
1457
1458         gi = container_of(cdev, struct gadget_info, cdev);
1459         spin_lock_irqsave(&gi->spinlock, flags);
1460         cdev = get_gadget_data(gadget);
1461         if (!cdev || gi->unbind) {
1462                 spin_unlock_irqrestore(&gi->spinlock, flags);
1463                 return 0;
1464         }
1465
1466         ret = composite_setup(gadget, ctrl);
1467         spin_unlock_irqrestore(&gi->spinlock, flags);
1468         return ret;
1469 }
1470
1471 static void configfs_composite_disconnect(struct usb_gadget *gadget)
1472 {
1473         struct usb_composite_dev *cdev;
1474         struct gadget_info *gi;
1475         unsigned long flags;
1476
1477         cdev = get_gadget_data(gadget);
1478         if (!cdev)
1479                 return;
1480
1481         gi = container_of(cdev, struct gadget_info, cdev);
1482         spin_lock_irqsave(&gi->spinlock, flags);
1483         cdev = get_gadget_data(gadget);
1484         if (!cdev || gi->unbind) {
1485                 spin_unlock_irqrestore(&gi->spinlock, flags);
1486                 return;
1487         }
1488
1489         composite_disconnect(gadget);
1490         spin_unlock_irqrestore(&gi->spinlock, flags);
1491 }
1492
1493 static void configfs_composite_suspend(struct usb_gadget *gadget)
1494 {
1495         struct usb_composite_dev *cdev;
1496         struct gadget_info *gi;
1497         unsigned long flags;
1498
1499         cdev = get_gadget_data(gadget);
1500         if (!cdev)
1501                 return;
1502
1503         gi = container_of(cdev, struct gadget_info, cdev);
1504         spin_lock_irqsave(&gi->spinlock, flags);
1505         cdev = get_gadget_data(gadget);
1506         if (!cdev || gi->unbind) {
1507                 spin_unlock_irqrestore(&gi->spinlock, flags);
1508                 return;
1509         }
1510
1511         composite_suspend(gadget);
1512         spin_unlock_irqrestore(&gi->spinlock, flags);
1513 }
1514
1515 static void configfs_composite_resume(struct usb_gadget *gadget)
1516 {
1517         struct usb_composite_dev *cdev;
1518         struct gadget_info *gi;
1519         unsigned long flags;
1520
1521         cdev = get_gadget_data(gadget);
1522         if (!cdev)
1523                 return;
1524
1525         gi = container_of(cdev, struct gadget_info, cdev);
1526         spin_lock_irqsave(&gi->spinlock, flags);
1527         cdev = get_gadget_data(gadget);
1528         if (!cdev || gi->unbind) {
1529                 spin_unlock_irqrestore(&gi->spinlock, flags);
1530                 return;
1531         }
1532
1533         composite_resume(gadget);
1534         spin_unlock_irqrestore(&gi->spinlock, flags);
1535 }
1536
1537 static const struct usb_gadget_driver configfs_driver_template = {
1538         .bind           = configfs_composite_bind,
1539         .unbind         = configfs_composite_unbind,
1540
1541         .setup          = configfs_composite_setup,
1542         .reset          = configfs_composite_disconnect,
1543         .disconnect     = configfs_composite_disconnect,
1544
1545         .suspend        = configfs_composite_suspend,
1546         .resume         = configfs_composite_resume,
1547
1548         .max_speed      = USB_SPEED_SUPER,
1549         .driver = {
1550                 .owner          = THIS_MODULE,
1551                 .name           = "configfs-gadget",
1552         },
1553         .match_existing_only = 1,
1554 };
1555
1556 static struct config_group *gadgets_make(
1557                 struct config_group *group,
1558                 const char *name)
1559 {
1560         struct gadget_info *gi;
1561
1562         gi = kzalloc(sizeof(*gi), GFP_KERNEL);
1563         if (!gi)
1564                 return ERR_PTR(-ENOMEM);
1565
1566         config_group_init_type_name(&gi->group, name, &gadget_root_type);
1567
1568         config_group_init_type_name(&gi->functions_group, "functions",
1569                         &functions_type);
1570         configfs_add_default_group(&gi->functions_group, &gi->group);
1571
1572         config_group_init_type_name(&gi->configs_group, "configs",
1573                         &config_desc_type);
1574         configfs_add_default_group(&gi->configs_group, &gi->group);
1575
1576         config_group_init_type_name(&gi->strings_group, "strings",
1577                         &gadget_strings_strings_type);
1578         configfs_add_default_group(&gi->strings_group, &gi->group);
1579
1580         config_group_init_type_name(&gi->os_desc_group, "os_desc",
1581                         &os_desc_type);
1582         configfs_add_default_group(&gi->os_desc_group, &gi->group);
1583
1584         gi->composite.bind = configfs_do_nothing;
1585         gi->composite.unbind = configfs_do_nothing;
1586         gi->composite.suspend = NULL;
1587         gi->composite.resume = NULL;
1588         gi->composite.max_speed = USB_SPEED_SUPER;
1589
1590         spin_lock_init(&gi->spinlock);
1591         mutex_init(&gi->lock);
1592         INIT_LIST_HEAD(&gi->string_list);
1593         INIT_LIST_HEAD(&gi->available_func);
1594
1595         composite_init_dev(&gi->cdev);
1596         gi->cdev.desc.bLength = USB_DT_DEVICE_SIZE;
1597         gi->cdev.desc.bDescriptorType = USB_DT_DEVICE;
1598         gi->cdev.desc.bcdDevice = cpu_to_le16(get_default_bcdDevice());
1599
1600         gi->composite.gadget_driver = configfs_driver_template;
1601
1602         gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
1603         gi->composite.name = gi->composite.gadget_driver.function;
1604
1605         if (!gi->composite.gadget_driver.function)
1606                 goto err;
1607
1608         return &gi->group;
1609 err:
1610         kfree(gi);
1611         return ERR_PTR(-ENOMEM);
1612 }
1613
1614 static void gadgets_drop(struct config_group *group, struct config_item *item)
1615 {
1616         config_item_put(item);
1617 }
1618
1619 static struct configfs_group_operations gadgets_ops = {
1620         .make_group     = &gadgets_make,
1621         .drop_item      = &gadgets_drop,
1622 };
1623
1624 static const struct config_item_type gadgets_type = {
1625         .ct_group_ops   = &gadgets_ops,
1626         .ct_owner       = THIS_MODULE,
1627 };
1628
1629 static struct configfs_subsystem gadget_subsys = {
1630         .su_group = {
1631                 .cg_item = {
1632                         .ci_namebuf = "usb_gadget",
1633                         .ci_type = &gadgets_type,
1634                 },
1635         },
1636         .su_mutex = __MUTEX_INITIALIZER(gadget_subsys.su_mutex),
1637 };
1638
1639 void unregister_gadget_item(struct config_item *item)
1640 {
1641         struct gadget_info *gi = to_gadget_info(item);
1642
1643         mutex_lock(&gi->lock);
1644         unregister_gadget(gi);
1645         mutex_unlock(&gi->lock);
1646 }
1647 EXPORT_SYMBOL_GPL(unregister_gadget_item);
1648
1649 static int __init gadget_cfs_init(void)
1650 {
1651         int ret;
1652
1653         config_group_init(&gadget_subsys.su_group);
1654
1655         ret = configfs_register_subsystem(&gadget_subsys);
1656         return ret;
1657 }
1658 module_init(gadget_cfs_init);
1659
1660 static void __exit gadget_cfs_exit(void)
1661 {
1662         configfs_unregister_subsystem(&gadget_subsys);
1663 }
1664 module_exit(gadget_cfs_exit);