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