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