drivers/usb/gadget/configfs.c

   1 #include <linux/configfs.h>
   2 #include <linux/module.h>
   3 #include <linux/slab.h>
   4 #include <linux/device.h>
   5 #include <linux/usb/composite.h>
   6 #include <linux/usb/gadget_configfs.h>
   7 #include "configfs.h"
   8
   9 int check_user_usb_string(const char *name,
  10                 struct usb_gadget_strings *stringtab_dev)
  11 {
  12         unsigned primary_lang;
  13         unsigned sub_lang;
  14         u16 num;
  15         int ret;
  16
  17         ret = kstrtou16(name, 0, &num);
  18         if (ret)
  19                 return ret;
  20
  21         primary_lang = num & 0x3ff;
  22         sub_lang = num >> 10;
  23
  24         /* simple sanity check for valid langid */
  25         switch (primary_lang) {
  26         case 0:
  27         case 0x62 ... 0xfe:
  28         case 0x100 ... 0x3ff:
  29                 return -EINVAL;
  30         }
  31         if (!sub_lang)
  32                 return -EINVAL;
  33
  34         stringtab_dev->language = num;
  35         return 0;
  36 }
  37
  38 #define MAX_NAME_LEN    40
  39 #define MAX_USB_STRING_LANGS 2
  40
  41 struct gadget_info {
  42         struct config_group group;
  43         struct config_group functions_group;
  44         struct config_group configs_group;
  45         struct config_group strings_group;
  46         struct config_group *default_groups[4];
  47
  48         struct mutex lock;
  49         struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
  50         struct list_head string_list;
  51         struct list_head available_func;
  52
  53         const char *udc_name;
  54 #ifdef CONFIG_USB_OTG
  55         struct usb_otg_descriptor otg;
  56 #endif
  57         struct usb_composite_driver composite;
  58         struct usb_composite_dev cdev;
  59 };
  60
  61 struct config_usb_cfg {
  62         struct config_group group;
  63         struct config_group strings_group;
  64         struct config_group *default_groups[2];
  65         struct list_head string_list;
  66         struct usb_configuration c;
  67         struct list_head func_list;
  68         struct usb_gadget_strings *gstrings[MAX_USB_STRING_LANGS + 1];
  69 };
  70
  71 struct gadget_strings {
  72         struct usb_gadget_strings stringtab_dev;
  73         struct usb_string strings[USB_GADGET_FIRST_AVAIL_IDX];
  74         char *manufacturer;
  75         char *product;
  76         char *serialnumber;
  77
  78         struct config_group group;
  79         struct list_head list;
  80 };
  81
  82 struct gadget_config_name {
  83         struct usb_gadget_strings stringtab_dev;
  84         struct usb_string strings;
  85         char *configuration;
  86
  87         struct config_group group;
  88         struct list_head list;
  89 };
  90
  91 static int usb_string_copy(const char *s, char **s_copy)
  92 {
  93         int ret;
  94         char *str;
  95         char *copy = *s_copy;
  96         ret = strlen(s);
  97         if (ret > 126)
  98                 return -EOVERFLOW;
  99
 100         str = kstrdup(s, GFP_KERNEL);
 101         if (!str)
 102                 return -ENOMEM;
 103         if (str[ret - 1] == '\n')
 104                 str[ret - 1] = '\0';
 105         kfree(copy);
 106         *s_copy = str;
 107         return 0;
 108 }
 109
 110 CONFIGFS_ATTR_STRUCT(gadget_info);
 111 CONFIGFS_ATTR_STRUCT(config_usb_cfg);
 112
 113 #define GI_DEVICE_DESC_ITEM_ATTR(name)  \
 114         static struct gadget_info_attribute gadget_cdev_desc_##name = \
 115                 __CONFIGFS_ATTR(name,  S_IRUGO | S_IWUSR,               \
 116                                 gadget_dev_desc_##name##_show,          \
 117                                 gadget_dev_desc_##name##_store)
 118
 119 #define GI_DEVICE_DESC_SIMPLE_R_u8(__name)      \
 120         static ssize_t gadget_dev_desc_##__name##_show(struct gadget_info *gi, \
 121                         char *page)     \
 122 {       \
 123         return sprintf(page, "0x%02x\n", gi->cdev.desc.__name); \
 124 }
 125
 126 #define GI_DEVICE_DESC_SIMPLE_R_u16(__name)     \
 127         static ssize_t gadget_dev_desc_##__name##_show(struct gadget_info *gi, \
 128                         char *page)     \
 129 {       \
 130         return sprintf(page, "0x%04x\n", le16_to_cpup(&gi->cdev.desc.__name)); \
 131 }
 132
 133
 134 #define GI_DEVICE_DESC_SIMPLE_W_u8(_name)               \
 135         static ssize_t gadget_dev_desc_##_name##_store(struct gadget_info *gi, \
 136                 const char *page, size_t len)           \
 137 {                                                       \
 138         u8 val;                                         \
 139         int ret;                                        \
 140         ret = kstrtou8(page, 0, &val);                  \
 141         if (ret)                                        \
 142                 return ret;                             \
 143         gi->cdev.desc._name = val;                      \
 144         return len;                                     \
 145 }
 146
 147 #define GI_DEVICE_DESC_SIMPLE_W_u16(_name)      \
 148         static ssize_t gadget_dev_desc_##_name##_store(struct gadget_info *gi, \
 149                 const char *page, size_t len)           \
 150 {                                                       \
 151         u16 val;                                        \
 152         int ret;                                        \
 153         ret = kstrtou16(page, 0, &val);                 \
 154         if (ret)                                        \
 155                 return ret;                             \
 156         gi->cdev.desc._name = cpu_to_le16p(&val);       \
 157         return len;                                     \
 158 }
 159
 160 #define GI_DEVICE_DESC_SIMPLE_RW(_name, _type)  \
 161         GI_DEVICE_DESC_SIMPLE_R_##_type(_name)  \
 162         GI_DEVICE_DESC_SIMPLE_W_##_type(_name)
 163
 164 GI_DEVICE_DESC_SIMPLE_R_u16(bcdUSB);
 165 GI_DEVICE_DESC_SIMPLE_RW(bDeviceClass, u8);
 166 GI_DEVICE_DESC_SIMPLE_RW(bDeviceSubClass, u8);
 167 GI_DEVICE_DESC_SIMPLE_RW(bDeviceProtocol, u8);
 168 GI_DEVICE_DESC_SIMPLE_RW(bMaxPacketSize0, u8);
 169 GI_DEVICE_DESC_SIMPLE_RW(idVendor, u16);
 170 GI_DEVICE_DESC_SIMPLE_RW(idProduct, u16);
 171 GI_DEVICE_DESC_SIMPLE_R_u16(bcdDevice);
 172
 173 static ssize_t is_valid_bcd(u16 bcd_val)
 174 {
 175         if ((bcd_val & 0xf) > 9)
 176                 return -EINVAL;
 177         if (((bcd_val >> 4) & 0xf) > 9)
 178                 return -EINVAL;
 179         if (((bcd_val >> 8) & 0xf) > 9)
 180                 return -EINVAL;
 181         if (((bcd_val >> 12) & 0xf) > 9)
 182                 return -EINVAL;
 183         return 0;
 184 }
 185
 186 static ssize_t gadget_dev_desc_bcdDevice_store(struct gadget_info *gi,
 187                 const char *page, size_t len)
 188 {
 189         u16 bcdDevice;
 190         int ret;
 191
 192         ret = kstrtou16(page, 0, &bcdDevice);
 193         if (ret)
 194                 return ret;
 195         ret = is_valid_bcd(bcdDevice);
 196         if (ret)
 197                 return ret;
 198
 199         gi->cdev.desc.bcdDevice = cpu_to_le16(bcdDevice);
 200         return len;
 201 }
 202
 203 static ssize_t gadget_dev_desc_bcdUSB_store(struct gadget_info *gi,
 204                 const char *page, size_t len)
 205 {
 206         u16 bcdUSB;
 207         int ret;
 208
 209         ret = kstrtou16(page, 0, &bcdUSB);
 210         if (ret)
 211                 return ret;
 212         ret = is_valid_bcd(bcdUSB);
 213         if (ret)
 214                 return ret;
 215
 216         gi->cdev.desc.bcdUSB = cpu_to_le16(bcdUSB);
 217         return len;
 218 }
 219
 220 static ssize_t gadget_dev_desc_UDC_show(struct gadget_info *gi, char *page)
 221 {
 222         return sprintf(page, "%s\n", gi->udc_name ?: "");
 223 }
 224
 225 static int unregister_gadget(struct gadget_info *gi)
 226 {
 227         int ret;
 228
 229         if (!gi->udc_name)
 230                 return -ENODEV;
 231
 232         ret = usb_gadget_unregister_driver(&gi->composite.gadget_driver);
 233         if (ret)
 234                 return ret;
 235         kfree(gi->udc_name);
 236         gi->udc_name = NULL;
 237         return 0;
 238 }
 239
 240 static ssize_t gadget_dev_desc_UDC_store(struct gadget_info *gi,
 241                 const char *page, size_t len)
 242 {
 243         char *name;
 244         int ret;
 245
 246         name = kstrdup(page, GFP_KERNEL);
 247         if (!name)
 248                 return -ENOMEM;
 249         if (name[len - 1] == '\n')
 250                 name[len - 1] = '\0';
 251
 252         mutex_lock(&gi->lock);
 253
 254         if (!strlen(name)) {
 255                 ret = unregister_gadget(gi);
 256                 if (ret)
 257                         goto err;
 258         } else {
 259                 if (gi->udc_name) {
 260                         ret = -EBUSY;
 261                         goto err;
 262                 }
 263                 ret = udc_attach_driver(name, &gi->composite.gadget_driver);
 264                 if (ret)
 265                         goto err;
 266                 gi->udc_name = name;
 267         }
 268         mutex_unlock(&gi->lock);
 269         return len;
 270 err:
 271         kfree(name);
 272         mutex_unlock(&gi->lock);
 273         return ret;
 274 }
 275
 276 GI_DEVICE_DESC_ITEM_ATTR(bDeviceClass);
 277 GI_DEVICE_DESC_ITEM_ATTR(bDeviceSubClass);
 278 GI_DEVICE_DESC_ITEM_ATTR(bDeviceProtocol);
 279 GI_DEVICE_DESC_ITEM_ATTR(bMaxPacketSize0);
 280 GI_DEVICE_DESC_ITEM_ATTR(idVendor);
 281 GI_DEVICE_DESC_ITEM_ATTR(idProduct);
 282 GI_DEVICE_DESC_ITEM_ATTR(bcdDevice);
 283 GI_DEVICE_DESC_ITEM_ATTR(bcdUSB);
 284 GI_DEVICE_DESC_ITEM_ATTR(UDC);
 285
 286 static struct configfs_attribute *gadget_root_attrs[] = {
 287         &gadget_cdev_desc_bDeviceClass.attr,
 288         &gadget_cdev_desc_bDeviceSubClass.attr,
 289         &gadget_cdev_desc_bDeviceProtocol.attr,
 290         &gadget_cdev_desc_bMaxPacketSize0.attr,
 291         &gadget_cdev_desc_idVendor.attr,
 292         &gadget_cdev_desc_idProduct.attr,
 293         &gadget_cdev_desc_bcdDevice.attr,
 294         &gadget_cdev_desc_bcdUSB.attr,
 295         &gadget_cdev_desc_UDC.attr,
 296         NULL,
 297 };
 298
 299 static inline struct gadget_info *to_gadget_info(struct config_item *item)
 300 {
 301          return container_of(to_config_group(item), struct gadget_info, group);
 302 }
 303
 304 static inline struct gadget_strings *to_gadget_strings(struct config_item *item)
 305 {
 306          return container_of(to_config_group(item), struct gadget_strings,
 307                          group);
 308 }
 309
 310 static inline struct gadget_config_name *to_gadget_config_name(
 311                 struct config_item *item)
 312 {
 313          return container_of(to_config_group(item), struct gadget_config_name,
 314                          group);
 315 }
 316
 317 static inline struct config_usb_cfg *to_config_usb_cfg(struct config_item *item)
 318 {
 319         return container_of(to_config_group(item), struct config_usb_cfg,
 320                         group);
 321 }
 322
 323 static inline struct usb_function_instance *to_usb_function_instance(
 324                 struct config_item *item)
 325 {
 326          return container_of(to_config_group(item),
 327                          struct usb_function_instance, group);
 328 }
 329
 330 static void gadget_info_attr_release(struct config_item *item)
 331 {
 332         struct gadget_info *gi = to_gadget_info(item);
 333
 334         WARN_ON(!list_empty(&gi->cdev.configs));
 335         WARN_ON(!list_empty(&gi->string_list));
 336         WARN_ON(!list_empty(&gi->available_func));
 337         kfree(gi->composite.gadget_driver.function);
 338         kfree(gi);
 339 }
 340
 341 CONFIGFS_ATTR_OPS(gadget_info);
 342
 343 static struct configfs_item_operations gadget_root_item_ops = {
 344         .release                = gadget_info_attr_release,
 345         .show_attribute         = gadget_info_attr_show,
 346         .store_attribute        = gadget_info_attr_store,
 347 };
 348
 349 static void gadget_config_attr_release(struct config_item *item)
 350 {
 351         struct config_usb_cfg *cfg = to_config_usb_cfg(item);
 352
 353         WARN_ON(!list_empty(&cfg->c.functions));
 354         list_del(&cfg->c.list);
 355         kfree(cfg->c.label);
 356         kfree(cfg);
 357 }
 358
 359 static int config_usb_cfg_link(
 360         struct config_item *usb_cfg_ci,
 361         struct config_item *usb_func_ci)
 362 {
 363         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
 364         struct usb_composite_dev *cdev = cfg->c.cdev;
 365         struct gadget_info *gi = container_of(cdev, struct gadget_info, cdev);
 366
 367         struct config_group *group = to_config_group(usb_func_ci);
 368         struct usb_function_instance *fi = container_of(group,
 369                         struct usb_function_instance, group);
 370         struct usb_function_instance *a_fi;
 371         struct usb_function *f;
 372         int ret;
 373
 374         mutex_lock(&gi->lock);
 375         /*
 376          * Make sure this function is from within our _this_ gadget and not
 377          * from another gadget or a random directory.
 378          * Also a function instance can only be linked once.
 379          */
 380         list_for_each_entry(a_fi, &gi->available_func, cfs_list) {
 381                 if (a_fi == fi)
 382                         break;
 383         }
 384         if (a_fi != fi) {
 385                 ret = -EINVAL;
 386                 goto out;
 387         }
 388
 389         list_for_each_entry(f, &cfg->func_list, list) {
 390                 if (f->fi == fi) {
 391                         ret = -EEXIST;
 392                         goto out;
 393                 }
 394         }
 395
 396         f = usb_get_function(fi);
 397         if (IS_ERR(f)) {
 398                 ret = PTR_ERR(f);
 399                 goto out;
 400         }
 401
 402         /* stash the function until we bind it to the gadget */
 403         list_add_tail(&f->list, &cfg->func_list);
 404         ret = 0;
 405 out:
 406         mutex_unlock(&gi->lock);
 407         return ret;
 408 }
 409
 410 static int config_usb_cfg_unlink(
 411         struct config_item *usb_cfg_ci,
 412         struct config_item *usb_func_ci)
 413 {
 414         struct config_usb_cfg *cfg = to_config_usb_cfg(usb_cfg_ci);
 415         struct usb_composite_dev *cdev = cfg->c.cdev;
 416         struct gadget_info *gi = container_of(cdev, struct gadget_info, cdev);
 417
 418         struct config_group *group = to_config_group(usb_func_ci);
 419         struct usb_function_instance *fi = container_of(group,
 420                         struct usb_function_instance, group);
 421         struct usb_function *f;
 422
 423         /*
 424          * ideally I would like to forbid to unlink functions while a gadget is
 425          * bound to an UDC. Since this isn't possible at the moment, we simply
 426          * force an unbind, the function is available here and then we can
 427          * remove the function.
 428          */
 429         mutex_lock(&gi->lock);
 430         if (gi->udc_name)
 431                 unregister_gadget(gi);
 432         WARN_ON(gi->udc_name);
 433
 434         list_for_each_entry(f, &cfg->func_list, list) {
 435                 if (f->fi == fi) {
 436                         list_del(&f->list);
 437                         usb_put_function(f);
 438                         mutex_unlock(&gi->lock);
 439                         return 0;
 440                 }
 441         }
 442         mutex_unlock(&gi->lock);
 443         WARN(1, "Unable to locate function to unbind\n");
 444         return 0;
 445 }
 446
 447 CONFIGFS_ATTR_OPS(config_usb_cfg);
 448
 449 static struct configfs_item_operations gadget_config_item_ops = {
 450         .release                = gadget_config_attr_release,
 451         .show_attribute         = config_usb_cfg_attr_show,
 452         .store_attribute        = config_usb_cfg_attr_store,
 453         .allow_link             = config_usb_cfg_link,
 454         .drop_link              = config_usb_cfg_unlink,
 455 };
 456
 457
 458 static ssize_t gadget_config_desc_MaxPower_show(struct config_usb_cfg *cfg,
 459                 char *page)
 460 {
 461         return sprintf(page, "%u\n", cfg->c.MaxPower);
 462 }
 463
 464 static ssize_t gadget_config_desc_MaxPower_store(struct config_usb_cfg *cfg,
 465                 const char *page, size_t len)
 466 {
 467         u16 val;
 468         int ret;
 469         ret = kstrtou16(page, 0, &val);
 470         if (ret)
 471                 return ret;
 472         if (DIV_ROUND_UP(val, 8) > 0xff)
 473                 return -ERANGE;
 474         cfg->c.MaxPower = val;
 475         return len;
 476 }
 477
 478 static ssize_t gadget_config_desc_bmAttributes_show(struct config_usb_cfg *cfg,
 479                 char *page)
 480 {
 481         return sprintf(page, "0x%02x\n", cfg->c.bmAttributes);
 482 }
 483
 484 static ssize_t gadget_config_desc_bmAttributes_store(struct config_usb_cfg *cfg,
 485                 const char *page, size_t len)
 486 {
 487         u8 val;
 488         int ret;
 489         ret = kstrtou8(page, 0, &val);
 490         if (ret)
 491                 return ret;
 492         if (!(val & USB_CONFIG_ATT_ONE))
 493                 return -EINVAL;
 494         if (val & ~(USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER |
 495                                 USB_CONFIG_ATT_WAKEUP))
 496                 return -EINVAL;
 497         cfg->c.bmAttributes = val;
 498         return len;
 499 }
 500
 501 #define CFG_CONFIG_DESC_ITEM_ATTR(name) \
 502         static struct config_usb_cfg_attribute gadget_usb_cfg_##name = \
 503                 __CONFIGFS_ATTR(name,  S_IRUGO | S_IWUSR,               \
 504                                 gadget_config_desc_##name##_show,       \
 505                                 gadget_config_desc_##name##_store)
 506
 507 CFG_CONFIG_DESC_ITEM_ATTR(MaxPower);
 508 CFG_CONFIG_DESC_ITEM_ATTR(bmAttributes);
 509
 510 static struct configfs_attribute *gadget_config_attrs[] = {
 511         &gadget_usb_cfg_MaxPower.attr,
 512         &gadget_usb_cfg_bmAttributes.attr,
 513         NULL,
 514 };
 515
 516 static struct config_item_type gadget_config_type = {
 517         .ct_item_ops    = &gadget_config_item_ops,
 518         .ct_attrs       = gadget_config_attrs,
 519         .ct_owner       = THIS_MODULE,
 520 };
 521
 522 static struct config_item_type gadget_root_type = {
 523         .ct_item_ops    = &gadget_root_item_ops,
 524         .ct_attrs       = gadget_root_attrs,
 525         .ct_owner       = THIS_MODULE,
 526 };
 527
 528 static void composite_init_dev(struct usb_composite_dev *cdev)
 529 {
 530         spin_lock_init(&cdev->lock);
 531         INIT_LIST_HEAD(&cdev->configs);
 532         INIT_LIST_HEAD(&cdev->gstrings);
 533 }
 534
 535 static struct config_group *function_make(
 536                 struct config_group *group,
 537                 const char *name)
 538 {
 539         struct gadget_info *gi;
 540         struct usb_function_instance *fi;
 541         char buf[MAX_NAME_LEN];
 542         char *func_name;
 543         char *instance_name;
 544         int ret;
 545
 546         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
 547         if (ret >= MAX_NAME_LEN)
 548                 return ERR_PTR(-ENAMETOOLONG);
 549
 550         func_name = buf;
 551         instance_name = strchr(func_name, '.');
 552         if (!instance_name) {
 553                 pr_err("Unable to locate . in FUNC.INSTANCE\n");
 554                 return ERR_PTR(-EINVAL);
 555         }
 556         *instance_name = '\0';
 557         instance_name++;
 558
 559         fi = usb_get_function_instance(func_name);
 560         if (IS_ERR(fi))
 561                 return ERR_CAST(fi);
 562
 563         ret = config_item_set_name(&fi->group.cg_item, name);
 564         if (ret) {
 565                 usb_put_function_instance(fi);
 566                 return ERR_PTR(ret);
 567         }
 568         if (fi->set_inst_name) {
 569                 ret = fi->set_inst_name(fi, instance_name);
 570                 if (ret) {
 571                         usb_put_function_instance(fi);
 572                         return ERR_PTR(ret);
 573                 }
 574         }
 575
 576         gi = container_of(group, struct gadget_info, functions_group);
 577
 578         mutex_lock(&gi->lock);
 579         list_add_tail(&fi->cfs_list, &gi->available_func);
 580         mutex_unlock(&gi->lock);
 581         return &fi->group;
 582 }
 583
 584 static void function_drop(
 585                 struct config_group *group,
 586                 struct config_item *item)
 587 {
 588         struct usb_function_instance *fi = to_usb_function_instance(item);
 589         struct gadget_info *gi;
 590
 591         gi = container_of(group, struct gadget_info, functions_group);
 592
 593         mutex_lock(&gi->lock);
 594         list_del(&fi->cfs_list);
 595         mutex_unlock(&gi->lock);
 596         config_item_put(item);
 597 }
 598
 599 static struct configfs_group_operations functions_ops = {
 600         .make_group     = &function_make,
 601         .drop_item      = &function_drop,
 602 };
 603
 604 static struct config_item_type functions_type = {
 605         .ct_group_ops   = &functions_ops,
 606         .ct_owner       = THIS_MODULE,
 607 };
 608
 609 CONFIGFS_ATTR_STRUCT(gadget_config_name);
 610 GS_STRINGS_RW(gadget_config_name, configuration);
 611
 612 static struct configfs_attribute *gadget_config_name_langid_attrs[] = {
 613         &gadget_config_name_configuration.attr,
 614         NULL,
 615 };
 616
 617 static void gadget_config_name_attr_release(struct config_item *item)
 618 {
 619         struct gadget_config_name *cn = to_gadget_config_name(item);
 620
 621         kfree(cn->configuration);
 622
 623         list_del(&cn->list);
 624         kfree(cn);
 625 }
 626
 627 USB_CONFIG_STRING_RW_OPS(gadget_config_name);
 628 USB_CONFIG_STRINGS_LANG(gadget_config_name, config_usb_cfg);
 629
 630 static struct config_group *config_desc_make(
 631                 struct config_group *group,
 632                 const char *name)
 633 {
 634         struct gadget_info *gi;
 635         struct config_usb_cfg *cfg;
 636         char buf[MAX_NAME_LEN];
 637         char *num_str;
 638         u8 num;
 639         int ret;
 640
 641         gi = container_of(group, struct gadget_info, configs_group);
 642         ret = snprintf(buf, MAX_NAME_LEN, "%s", name);
 643         if (ret >= MAX_NAME_LEN)
 644                 return ERR_PTR(-ENAMETOOLONG);
 645
 646         num_str = strchr(buf, '.');
 647         if (!num_str) {
 648                 pr_err("Unable to locate . in name.bConfigurationValue\n");
 649                 return ERR_PTR(-EINVAL);
 650         }
 651
 652         *num_str = '\0';
 653         num_str++;
 654
 655         if (!strlen(buf))
 656                 return ERR_PTR(-EINVAL);
 657
 658         ret = kstrtou8(num_str, 0, &num);
 659         if (ret)
 660                 return ERR_PTR(ret);
 661
 662         cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
 663         if (!cfg)
 664                 return ERR_PTR(-ENOMEM);
 665         cfg->c.label = kstrdup(buf, GFP_KERNEL);
 666         if (!cfg->c.label) {
 667                 ret = -ENOMEM;
 668                 goto err;
 669         }
 670         cfg->c.bConfigurationValue = num;
 671         cfg->c.MaxPower = CONFIG_USB_GADGET_VBUS_DRAW;
 672         cfg->c.bmAttributes = USB_CONFIG_ATT_ONE;
 673         INIT_LIST_HEAD(&cfg->string_list);
 674         INIT_LIST_HEAD(&cfg->func_list);
 675
 676         cfg->group.default_groups = cfg->default_groups;
 677         cfg->default_groups[0] = &cfg->strings_group;
 678
 679         config_group_init_type_name(&cfg->group, name,
 680                                 &gadget_config_type);
 681         config_group_init_type_name(&cfg->strings_group, "strings",
 682                         &gadget_config_name_strings_type);
 683
 684         ret = usb_add_config_only(&gi->cdev, &cfg->c);
 685         if (ret)
 686                 goto err;
 687
 688         return &cfg->group;
 689 err:
 690         kfree(cfg->c.label);
 691         kfree(cfg);
 692         return ERR_PTR(ret);
 693 }
 694
 695 static void config_desc_drop(
 696                 struct config_group *group,
 697                 struct config_item *item)
 698 {
 699         config_item_put(item);
 700 }
 701
 702 static struct configfs_group_operations config_desc_ops = {
 703         .make_group     = &config_desc_make,
 704         .drop_item      = &config_desc_drop,
 705 };
 706
 707 static struct config_item_type config_desc_type = {
 708         .ct_group_ops   = &config_desc_ops,
 709         .ct_owner       = THIS_MODULE,
 710 };
 711
 712 CONFIGFS_ATTR_STRUCT(gadget_strings);
 713 GS_STRINGS_RW(gadget_strings, manufacturer);
 714 GS_STRINGS_RW(gadget_strings, product);
 715 GS_STRINGS_RW(gadget_strings, serialnumber);
 716
 717 static struct configfs_attribute *gadget_strings_langid_attrs[] = {
 718         &gadget_strings_manufacturer.attr,
 719         &gadget_strings_product.attr,
 720         &gadget_strings_serialnumber.attr,
 721         NULL,
 722 };
 723
 724 static void gadget_strings_attr_release(struct config_item *item)
 725 {
 726         struct gadget_strings *gs = to_gadget_strings(item);
 727
 728         kfree(gs->manufacturer);
 729         kfree(gs->product);
 730         kfree(gs->serialnumber);
 731
 732         list_del(&gs->list);
 733         kfree(gs);
 734 }
 735
 736 USB_CONFIG_STRING_RW_OPS(gadget_strings);
 737 USB_CONFIG_STRINGS_LANG(gadget_strings, gadget_info);
 738
 739 static int configfs_do_nothing(struct usb_composite_dev *cdev)
 740 {
 741         WARN_ON(1);
 742         return -EINVAL;
 743 }
 744
 745 int composite_dev_prepare(struct usb_composite_driver *composite,
 746                 struct usb_composite_dev *dev);
 747
 748 static void purge_configs_funcs(struct gadget_info *gi)
 749 {
 750         struct usb_configuration        *c;
 751
 752         list_for_each_entry(c, &gi->cdev.configs, list) {
 753                 struct usb_function *f, *tmp;
 754                 struct config_usb_cfg *cfg;
 755
 756                 cfg = container_of(c, struct config_usb_cfg, c);
 757
 758                 list_for_each_entry_safe(f, tmp, &c->functions, list) {
 759
 760                         list_move_tail(&f->list, &cfg->func_list);
 761                         if (f->unbind) {
 762                                 dev_err(&gi->cdev.gadget->dev, "unbind function"
 763                                                 " '%s'/%p\n", f->name, f);
 764                                 f->unbind(c, f);
 765                         }
 766                 }
 767                 c->next_interface_id = 0;
 768                 c->superspeed = 0;
 769                 c->highspeed = 0;
 770                 c->fullspeed = 0;
 771         }
 772 }
 773
 774 static int configfs_composite_bind(struct usb_gadget *gadget,
 775                 struct usb_gadget_driver *gdriver)
 776 {
 777         struct usb_composite_driver     *composite = to_cdriver(gdriver);
 778         struct gadget_info              *gi = container_of(composite,
 779                                                 struct gadget_info, composite);
 780         struct usb_composite_dev        *cdev = &gi->cdev;
 781         struct usb_configuration        *c;
 782         struct usb_string               *s;
 783         unsigned                        i;
 784         int                             ret;
 785
 786         /* the gi->lock is hold by the caller */
 787         cdev->gadget = gadget;
 788         set_gadget_data(gadget, cdev);
 789         ret = composite_dev_prepare(composite, cdev);
 790         if (ret)
 791                 return ret;
 792         /* and now the gadget bind */
 793         ret = -EINVAL;
 794
 795         if (list_empty(&gi->cdev.configs)) {
 796                 pr_err("Need at least one configuration in %s.\n",
 797                                 gi->composite.name);
 798                 goto err_comp_cleanup;
 799         }
 800
 801
 802         list_for_each_entry(c, &gi->cdev.configs, list) {
 803                 struct config_usb_cfg *cfg;
 804
 805                 cfg = container_of(c, struct config_usb_cfg, c);
 806                 if (list_empty(&cfg->func_list)) {
 807                         pr_err("Config %s/%d of %s needs at least one function.\n",
 808                               c->label, c->bConfigurationValue,
 809                               gi->composite.name);
 810                         goto err_comp_cleanup;
 811                 }
 812         }
 813
 814         /* init all strings */
 815         if (!list_empty(&gi->string_list)) {
 816                 struct gadget_strings *gs;
 817
 818                 i = 0;
 819                 list_for_each_entry(gs, &gi->string_list, list) {
 820
 821                         gi->gstrings[i] = &gs->stringtab_dev;
 822                         gs->stringtab_dev.strings = gs->strings;
 823                         gs->strings[USB_GADGET_MANUFACTURER_IDX].s =
 824                                 gs->manufacturer;
 825                         gs->strings[USB_GADGET_PRODUCT_IDX].s = gs->product;
 826                         gs->strings[USB_GADGET_SERIAL_IDX].s = gs->serialnumber;
 827                         i++;
 828                 }
 829                 gi->gstrings[i] = NULL;
 830                 s = usb_gstrings_attach(&gi->cdev, gi->gstrings,
 831                                 USB_GADGET_FIRST_AVAIL_IDX);
 832                 if (IS_ERR(s)) {
 833                         ret = PTR_ERR(s);
 834                         goto err_comp_cleanup;
 835                 }
 836
 837                 gi->cdev.desc.iManufacturer = s[USB_GADGET_MANUFACTURER_IDX].id;
 838                 gi->cdev.desc.iProduct = s[USB_GADGET_PRODUCT_IDX].id;
 839                 gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
 840         }
 841
 842         /* Go through all configs, attach all functions */
 843         list_for_each_entry(c, &gi->cdev.configs, list) {
 844                 struct config_usb_cfg *cfg;
 845                 struct usb_function *f;
 846                 struct usb_function *tmp;
 847                 struct gadget_config_name *cn;
 848
 849                 cfg = container_of(c, struct config_usb_cfg, c);
 850                 if (!list_empty(&cfg->string_list)) {
 851                         i = 0;
 852                         list_for_each_entry(cn, &cfg->string_list, list) {
 853                                 cfg->gstrings[i] = &cn->stringtab_dev;
 854                                 cn->stringtab_dev.strings = &cn->strings;
 855                                 cn->strings.s = cn->configuration;
 856                                 i++;
 857                         }
 858                         cfg->gstrings[i] = NULL;
 859                         s = usb_gstrings_attach(&gi->cdev, cfg->gstrings, 1);
 860                         if (IS_ERR(s)) {
 861                                 ret = PTR_ERR(s);
 862                                 goto err_comp_cleanup;
 863                         }
 864                         c->iConfiguration = s[0].id;
 865                 }
 866
 867                 list_for_each_entry_safe(f, tmp, &cfg->func_list, list) {
 868                         list_del(&f->list);
 869                         ret = usb_add_function(c, f);
 870                         if (ret) {
 871                                 list_add(&f->list, &cfg->func_list);
 872                                 goto err_purge_funcs;
 873                         }
 874                 }
 875                 usb_ep_autoconfig_reset(cdev->gadget);
 876         }
 877         usb_ep_autoconfig_reset(cdev->gadget);
 878         return 0;
 879
 880 err_purge_funcs:
 881         purge_configs_funcs(gi);
 882 err_comp_cleanup:
 883         composite_dev_cleanup(cdev);
 884         return ret;
 885 }
 886
 887 static void configfs_composite_unbind(struct usb_gadget *gadget)
 888 {
 889         struct usb_composite_dev        *cdev;
 890         struct gadget_info              *gi;
 891
 892         /* the gi->lock is hold by the caller */
 893
 894         cdev = get_gadget_data(gadget);
 895         gi = container_of(cdev, struct gadget_info, cdev);
 896
 897         purge_configs_funcs(gi);
 898         composite_dev_cleanup(cdev);
 899         usb_ep_autoconfig_reset(cdev->gadget);
 900         cdev->gadget = NULL;
 901         set_gadget_data(gadget, NULL);
 902 }
 903
 904 static const struct usb_gadget_driver configfs_driver_template = {
 905         .bind           = configfs_composite_bind,
 906         .unbind         = configfs_composite_unbind,
 907
 908         .setup          = composite_setup,
 909         .disconnect     = composite_disconnect,
 910
 911         .max_speed      = USB_SPEED_SUPER,
 912         .driver = {
 913                 .owner          = THIS_MODULE,
 914                 .name           = "configfs-gadget",
 915         },
 916 };
 917
 918 static struct config_group *gadgets_make(
 919                 struct config_group *group,
 920                 const char *name)
 921 {
 922         struct gadget_info *gi;
 923
 924         gi = kzalloc(sizeof(*gi), GFP_KERNEL);
 925         if (!gi)
 926                 return ERR_PTR(-ENOMEM);
 927
 928         gi->group.default_groups = gi->default_groups;
 929         gi->group.default_groups[0] = &gi->functions_group;
 930         gi->group.default_groups[1] = &gi->configs_group;
 931         gi->group.default_groups[2] = &gi->strings_group;
 932
 933         config_group_init_type_name(&gi->functions_group, "functions",
 934                         &functions_type);
 935         config_group_init_type_name(&gi->configs_group, "configs",
 936                         &config_desc_type);
 937         config_group_init_type_name(&gi->strings_group, "strings",
 938                         &gadget_strings_strings_type);
 939
 940         gi->composite.bind = configfs_do_nothing;
 941         gi->composite.unbind = configfs_do_nothing;
 942         gi->composite.suspend = NULL;
 943         gi->composite.resume = NULL;
 944         gi->composite.max_speed = USB_SPEED_SUPER;
 945
 946         mutex_init(&gi->lock);
 947         INIT_LIST_HEAD(&gi->string_list);
 948         INIT_LIST_HEAD(&gi->available_func);
 949
 950         composite_init_dev(&gi->cdev);
 951         gi->cdev.desc.bLength = USB_DT_DEVICE_SIZE;
 952         gi->cdev.desc.bDescriptorType = USB_DT_DEVICE;
 953         gi->cdev.desc.bcdDevice = cpu_to_le16(get_default_bcdDevice());
 954
 955         gi->composite.gadget_driver = configfs_driver_template;
 956
 957         gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
 958         gi->composite.name = gi->composite.gadget_driver.function;
 959
 960         if (!gi->composite.gadget_driver.function)
 961                 goto err;
 962
 963 #ifdef CONFIG_USB_OTG
 964         gi->otg.bLength = sizeof(struct usb_otg_descriptor);
 965         gi->otg.bDescriptorType = USB_DT_OTG;
 966         gi->otg.bmAttributes = USB_OTG_SRP | USB_OTG_HNP;
 967 #endif
 968
 969         config_group_init_type_name(&gi->group, name,
 970                                 &gadget_root_type);
 971         return &gi->group;
 972 err:
 973         kfree(gi);
 974         return ERR_PTR(-ENOMEM);
 975 }
 976
 977 static void gadgets_drop(struct config_group *group, struct config_item *item)
 978 {
 979         config_item_put(item);
 980 }
 981
 982 static struct configfs_group_operations gadgets_ops = {
 983         .make_group     = &gadgets_make,
 984         .drop_item      = &gadgets_drop,
 985 };
 986
 987 static struct config_item_type gadgets_type = {
 988         .ct_group_ops   = &gadgets_ops,
 989         .ct_owner       = THIS_MODULE,
 990 };
 991
 992 static struct configfs_subsystem gadget_subsys = {
 993         .su_group = {
 994                 .cg_item = {
 995                         .ci_namebuf = "usb_gadget",
 996                         .ci_type = &gadgets_type,
 997                 },
 998         },
 999         .su_mutex = __MUTEX_INITIALIZER(gadget_subsys.su_mutex),
1000 };
1001
1002 void unregister_gadget_item(struct config_item *item)
1003 {
1004         struct gadget_info *gi = to_gadget_info(item);
1005
1006         unregister_gadget(gi);
1007 }
1008 EXPORT_SYMBOL_GPL(unregister_gadget_item);
1009
1010 static int __init gadget_cfs_init(void)
1011 {
1012         int ret;
1013
1014         config_group_init(&gadget_subsys.su_group);
1015
1016         ret = configfs_register_subsystem(&gadget_subsys);
1017         return ret;
1018 }
1019 module_init(gadget_cfs_init);
1020
1021 static void __exit gadget_cfs_exit(void)
1022 {
1023         configfs_unregister_subsystem(&gadget_subsys);
1024 }
1025 module_exit(gadget_cfs_exit);