drivers/usb/gadget/f_dfu.c

   1 /*
   2  * f_dfu.c -- Device Firmware Update USB function
   3  *
   4  * Copyright (C) 2012 Samsung Electronics
   5  * authors: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
   6  *          Lukasz Majewski <l.majewski@samsung.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include <errno.h>
  24 #include <common.h>
  25 #include <malloc.h>
  26
  27 #include <linux/usb/ch9.h>
  28 #include <linux/usb/gadget.h>
  29 #include <linux/usb/composite.h>
  30
  31 #include <dfu.h>
  32 #include "f_dfu.h"
  33
  34 struct f_dfu {
  35         struct usb_function             usb_function;
  36
  37         struct usb_descriptor_header    **function;
  38         struct usb_string               *strings;
  39
  40         /* when configured, we have one config */
  41         u8                              config;
  42         u8                              altsetting;
  43         enum dfu_state                  dfu_state;
  44         unsigned int                    dfu_status;
  45
  46         /* Send/received block number is handy for data integrity check */
  47         int                             blk_seq_num;
  48 };
  49
  50 typedef int (*dfu_state_fn) (struct f_dfu *,
  51                              const struct usb_ctrlrequest *,
  52                              struct usb_gadget *,
  53                              struct usb_request *);
  54
  55 static inline struct f_dfu *func_to_dfu(struct usb_function *f)
  56 {
  57         return container_of(f, struct f_dfu, usb_function);
  58 }
  59
  60 static const struct dfu_function_descriptor dfu_func = {
  61         .bLength =              sizeof dfu_func,
  62         .bDescriptorType =      DFU_DT_FUNC,
  63         .bmAttributes =         DFU_BIT_WILL_DETACH |
  64                                 DFU_BIT_MANIFESTATION_TOLERANT |
  65                                 DFU_BIT_CAN_UPLOAD |
  66                                 DFU_BIT_CAN_DNLOAD,
  67         .wDetachTimeOut =       0,
  68         .wTransferSize =        DFU_USB_BUFSIZ,
  69         .bcdDFUVersion =        __constant_cpu_to_le16(0x0110),
  70 };
  71
  72 static struct usb_interface_descriptor dfu_intf_runtime = {
  73         .bLength =              sizeof dfu_intf_runtime,
  74         .bDescriptorType =      USB_DT_INTERFACE,
  75         .bNumEndpoints =        0,
  76         .bInterfaceClass =      USB_CLASS_APP_SPEC,
  77         .bInterfaceSubClass =   1,
  78         .bInterfaceProtocol =   1,
  79         /* .iInterface = DYNAMIC */
  80 };
  81
  82 static struct usb_descriptor_header *dfu_runtime_descs[] = {
  83         (struct usb_descriptor_header *) &dfu_intf_runtime,
  84         NULL,
  85 };
  86
  87 static const struct usb_qualifier_descriptor dev_qualifier = {
  88         .bLength =              sizeof dev_qualifier,
  89         .bDescriptorType =      USB_DT_DEVICE_QUALIFIER,
  90         .bcdUSB =               __constant_cpu_to_le16(0x0200),
  91         .bDeviceClass =         USB_CLASS_VENDOR_SPEC,
  92         .bNumConfigurations =   1,
  93 };
  94
  95 static const char dfu_name[] = "Device Firmware Upgrade";
  96
  97 /*
  98  * static strings, in UTF-8
  99  *
 100  * dfu_generic configuration
 101  */
 102 static struct usb_string strings_dfu_generic[] = {
 103         [0].s = dfu_name,
 104         {  }                    /* end of list */
 105 };
 106
 107 static struct usb_gadget_strings stringtab_dfu_generic = {
 108         .language       = 0x0409,       /* en-us */
 109         .strings        = strings_dfu_generic,
 110 };
 111
 112 static struct usb_gadget_strings *dfu_generic_strings[] = {
 113         &stringtab_dfu_generic,
 114         NULL,
 115 };
 116
 117 /*
 118  * usb_function specific
 119  */
 120 static struct usb_gadget_strings stringtab_dfu = {
 121         .language       = 0x0409,       /* en-us */
 122         /*
 123          * .strings
 124          *
 125          * assigned during initialization,
 126          * depends on number of flash entities
 127          *
 128          */
 129 };
 130
 131 static struct usb_gadget_strings *dfu_strings[] = {
 132         &stringtab_dfu,
 133         NULL,
 134 };
 135
 136 /*-------------------------------------------------------------------------*/
 137
 138 static void dnload_request_complete(struct usb_ep *ep, struct usb_request *req)
 139 {
 140         struct f_dfu *f_dfu = req->context;
 141
 142         dfu_write(dfu_get_entity(f_dfu->altsetting), req->buf,
 143                   req->length, f_dfu->blk_seq_num);
 144
 145         if (req->length == 0)
 146                 puts("DOWNLOAD ... OK\nCtrl+C to exit ...\n");
 147 }
 148
 149 static void handle_getstatus(struct usb_request *req)
 150 {
 151         struct dfu_status *dstat = (struct dfu_status *)req->buf;
 152         struct f_dfu *f_dfu = req->context;
 153
 154         switch (f_dfu->dfu_state) {
 155         case DFU_STATE_dfuDNLOAD_SYNC:
 156         case DFU_STATE_dfuDNBUSY:
 157                 f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_IDLE;
 158                 break;
 159         case DFU_STATE_dfuMANIFEST_SYNC:
 160                 break;
 161         default:
 162                 break;
 163         }
 164
 165         /* send status response */
 166         dstat->bStatus = f_dfu->dfu_status;
 167         dstat->bwPollTimeout[0] = 0;
 168         dstat->bwPollTimeout[1] = 0;
 169         dstat->bwPollTimeout[2] = 0;
 170         dstat->bState = f_dfu->dfu_state;
 171         dstat->iString = 0;
 172 }
 173
 174 static void handle_getstate(struct usb_request *req)
 175 {
 176         struct f_dfu *f_dfu = req->context;
 177
 178         ((u8 *)req->buf)[0] = f_dfu->dfu_state;
 179         req->actual = sizeof(u8);
 180 }
 181
 182 static inline void to_dfu_mode(struct f_dfu *f_dfu)
 183 {
 184         f_dfu->usb_function.strings = dfu_strings;
 185         f_dfu->usb_function.hs_descriptors = f_dfu->function;
 186 }
 187
 188 static inline void to_runtime_mode(struct f_dfu *f_dfu)
 189 {
 190         f_dfu->usb_function.strings = NULL;
 191         f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
 192 }
 193
 194 static int handle_upload(struct usb_request *req, u16 len)
 195 {
 196         struct f_dfu *f_dfu = req->context;
 197
 198         return dfu_read(dfu_get_entity(f_dfu->altsetting), req->buf,
 199                         req->length, f_dfu->blk_seq_num);
 200 }
 201
 202 static int handle_dnload(struct usb_gadget *gadget, u16 len)
 203 {
 204         struct usb_composite_dev *cdev = get_gadget_data(gadget);
 205         struct usb_request *req = cdev->req;
 206         struct f_dfu *f_dfu = req->context;
 207
 208         if (len == 0)
 209                 f_dfu->dfu_state = DFU_STATE_dfuMANIFEST_SYNC;
 210
 211         req->complete = dnload_request_complete;
 212
 213         return len;
 214 }
 215
 216 /*-------------------------------------------------------------------------*/
 217 /* DFU state machine  */
 218 static int state_app_idle(struct f_dfu *f_dfu,
 219                           const struct usb_ctrlrequest *ctrl,
 220                           struct usb_gadget *gadget,
 221                           struct usb_request *req)
 222 {
 223         int value = 0;
 224
 225         switch (ctrl->bRequest) {
 226         case USB_REQ_DFU_GETSTATUS:
 227                 handle_getstatus(req);
 228                 value = RET_STAT_LEN;
 229                 break;
 230         case USB_REQ_DFU_GETSTATE:
 231                 handle_getstate(req);
 232                 break;
 233         case USB_REQ_DFU_DETACH:
 234                 f_dfu->dfu_state = DFU_STATE_appDETACH;
 235                 to_dfu_mode(f_dfu);
 236                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 237                 value = RET_ZLP;
 238                 break;
 239         default:
 240                 value = RET_STALL;
 241                 break;
 242         }
 243
 244         return value;
 245 }
 246
 247 static int state_app_detach(struct f_dfu *f_dfu,
 248                             const struct usb_ctrlrequest *ctrl,
 249                             struct usb_gadget *gadget,
 250                             struct usb_request *req)
 251 {
 252         int value = 0;
 253
 254         switch (ctrl->bRequest) {
 255         case USB_REQ_DFU_GETSTATUS:
 256                 handle_getstatus(req);
 257                 value = RET_STAT_LEN;
 258                 break;
 259         case USB_REQ_DFU_GETSTATE:
 260                 handle_getstate(req);
 261                 break;
 262         default:
 263                 f_dfu->dfu_state = DFU_STATE_appIDLE;
 264                 value = RET_STALL;
 265                 break;
 266         }
 267
 268         return value;
 269 }
 270
 271 static int state_dfu_idle(struct f_dfu *f_dfu,
 272                           const struct usb_ctrlrequest *ctrl,
 273                           struct usb_gadget *gadget,
 274                           struct usb_request *req)
 275 {
 276         u16 w_value = le16_to_cpu(ctrl->wValue);
 277         u16 len = le16_to_cpu(ctrl->wLength);
 278         int value = 0;
 279
 280         switch (ctrl->bRequest) {
 281         case USB_REQ_DFU_DNLOAD:
 282                 if (len == 0) {
 283                         f_dfu->dfu_state = DFU_STATE_dfuERROR;
 284                         value = RET_STALL;
 285                         break;
 286                 }
 287                 f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
 288                 f_dfu->blk_seq_num = w_value;
 289                 value = handle_dnload(gadget, len);
 290                 break;
 291         case USB_REQ_DFU_UPLOAD:
 292                 f_dfu->dfu_state = DFU_STATE_dfuUPLOAD_IDLE;
 293                 f_dfu->blk_seq_num = 0;
 294                 value = handle_upload(req, len);
 295                 break;
 296         case USB_REQ_DFU_ABORT:
 297                 /* no zlp? */
 298                 value = RET_ZLP;
 299                 break;
 300         case USB_REQ_DFU_GETSTATUS:
 301                 handle_getstatus(req);
 302                 value = RET_STAT_LEN;
 303                 break;
 304         case USB_REQ_DFU_GETSTATE:
 305                 handle_getstate(req);
 306                 break;
 307         case USB_REQ_DFU_DETACH:
 308                 /*
 309                  * Proprietary extension: 'detach' from idle mode and
 310                  * get back to runtime mode in case of USB Reset.  As
 311                  * much as I dislike this, we just can't use every USB
 312                  * bus reset to switch back to runtime mode, since at
 313                  * least the Linux USB stack likes to send a number of
 314                  * resets in a row :(
 315                  */
 316                 f_dfu->dfu_state =
 317                         DFU_STATE_dfuMANIFEST_WAIT_RST;
 318                 to_runtime_mode(f_dfu);
 319                 f_dfu->dfu_state = DFU_STATE_appIDLE;
 320                 break;
 321         default:
 322                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 323                 value = RET_STALL;
 324                 break;
 325         }
 326
 327         return value;
 328 }
 329
 330 static int state_dfu_dnload_sync(struct f_dfu *f_dfu,
 331                                  const struct usb_ctrlrequest *ctrl,
 332                                  struct usb_gadget *gadget,
 333                                  struct usb_request *req)
 334 {
 335         int value = 0;
 336
 337         switch (ctrl->bRequest) {
 338         case USB_REQ_DFU_GETSTATUS:
 339                 handle_getstatus(req);
 340                 value = RET_STAT_LEN;
 341                 break;
 342         case USB_REQ_DFU_GETSTATE:
 343                 handle_getstate(req);
 344                 break;
 345         default:
 346                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 347                 value = RET_STALL;
 348                 break;
 349         }
 350
 351         return value;
 352 }
 353
 354 static int state_dfu_dnbusy(struct f_dfu *f_dfu,
 355                             const struct usb_ctrlrequest *ctrl,
 356                             struct usb_gadget *gadget,
 357                             struct usb_request *req)
 358 {
 359         int value = 0;
 360
 361         switch (ctrl->bRequest) {
 362         case USB_REQ_DFU_GETSTATUS:
 363                 handle_getstatus(req);
 364                 value = RET_STAT_LEN;
 365                 break;
 366         default:
 367                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 368                 value = RET_STALL;
 369                 break;
 370         }
 371
 372         return value;
 373 }
 374
 375 static int state_dfu_dnload_idle(struct f_dfu *f_dfu,
 376                                  const struct usb_ctrlrequest *ctrl,
 377                                  struct usb_gadget *gadget,
 378                                  struct usb_request *req)
 379 {
 380         u16 w_value = le16_to_cpu(ctrl->wValue);
 381         u16 len = le16_to_cpu(ctrl->wLength);
 382         int value = 0;
 383
 384         switch (ctrl->bRequest) {
 385         case USB_REQ_DFU_DNLOAD:
 386                 f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
 387                 f_dfu->blk_seq_num = w_value;
 388                 value = handle_dnload(gadget, len);
 389                 break;
 390         case USB_REQ_DFU_ABORT:
 391                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 392                 value = RET_ZLP;
 393                 break;
 394         case USB_REQ_DFU_GETSTATUS:
 395                 handle_getstatus(req);
 396                 value = RET_STAT_LEN;
 397                 break;
 398         case USB_REQ_DFU_GETSTATE:
 399                 handle_getstate(req);
 400                 break;
 401         default:
 402                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 403                 value = RET_STALL;
 404                 break;
 405         }
 406
 407         return value;
 408 }
 409
 410 static int state_dfu_manifest_sync(struct f_dfu *f_dfu,
 411                                    const struct usb_ctrlrequest *ctrl,
 412                                    struct usb_gadget *gadget,
 413                                    struct usb_request *req)
 414 {
 415         int value = 0;
 416
 417         switch (ctrl->bRequest) {
 418         case USB_REQ_DFU_GETSTATUS:
 419                 /* We're MainfestationTolerant */
 420                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 421                 handle_getstatus(req);
 422                 f_dfu->blk_seq_num = 0;
 423                 value = RET_STAT_LEN;
 424                 break;
 425         case USB_REQ_DFU_GETSTATE:
 426                 handle_getstate(req);
 427                 break;
 428         default:
 429                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 430                 value = RET_STALL;
 431                 break;
 432         }
 433
 434         return value;
 435 }
 436
 437 static int state_dfu_upload_idle(struct f_dfu *f_dfu,
 438                                  const struct usb_ctrlrequest *ctrl,
 439                                  struct usb_gadget *gadget,
 440                                  struct usb_request *req)
 441 {
 442         u16 w_value = le16_to_cpu(ctrl->wValue);
 443         u16 len = le16_to_cpu(ctrl->wLength);
 444         int value = 0;
 445
 446         switch (ctrl->bRequest) {
 447         case USB_REQ_DFU_UPLOAD:
 448                 /* state transition if less data then requested */
 449                 f_dfu->blk_seq_num = w_value;
 450                 value = handle_upload(req, len);
 451                 if (value >= 0 && value < len)
 452                         f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 453                 break;
 454         case USB_REQ_DFU_ABORT:
 455                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 456                 /* no zlp? */
 457                 value = RET_ZLP;
 458                 break;
 459         case USB_REQ_DFU_GETSTATUS:
 460                 handle_getstatus(req);
 461                 value = RET_STAT_LEN;
 462                 break;
 463         case USB_REQ_DFU_GETSTATE:
 464                 handle_getstate(req);
 465                 break;
 466         default:
 467                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 468                 value = RET_STALL;
 469                 break;
 470         }
 471
 472         return value;
 473 }
 474
 475 static int state_dfu_error(struct f_dfu *f_dfu,
 476                                  const struct usb_ctrlrequest *ctrl,
 477                                  struct usb_gadget *gadget,
 478                                  struct usb_request *req)
 479 {
 480         int value = 0;
 481
 482         switch (ctrl->bRequest) {
 483         case USB_REQ_DFU_GETSTATUS:
 484                 handle_getstatus(req);
 485                 value = RET_STAT_LEN;
 486                 break;
 487         case USB_REQ_DFU_GETSTATE:
 488                 handle_getstate(req);
 489                 break;
 490         case USB_REQ_DFU_CLRSTATUS:
 491                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 492                 f_dfu->dfu_status = DFU_STATUS_OK;
 493                 /* no zlp? */
 494                 value = RET_ZLP;
 495                 break;
 496         default:
 497                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 498                 value = RET_STALL;
 499                 break;
 500         }
 501
 502         return value;
 503 }
 504
 505 static dfu_state_fn dfu_state[] = {
 506         state_app_idle,          /* DFU_STATE_appIDLE */
 507         state_app_detach,        /* DFU_STATE_appDETACH */
 508         state_dfu_idle,          /* DFU_STATE_dfuIDLE */
 509         state_dfu_dnload_sync,   /* DFU_STATE_dfuDNLOAD_SYNC */
 510         state_dfu_dnbusy,        /* DFU_STATE_dfuDNBUSY */
 511         state_dfu_dnload_idle,   /* DFU_STATE_dfuDNLOAD_IDLE */
 512         state_dfu_manifest_sync, /* DFU_STATE_dfuMANIFEST_SYNC */
 513         NULL,                    /* DFU_STATE_dfuMANIFEST */
 514         NULL,                    /* DFU_STATE_dfuMANIFEST_WAIT_RST */
 515         state_dfu_upload_idle,   /* DFU_STATE_dfuUPLOAD_IDLE */
 516         state_dfu_error          /* DFU_STATE_dfuERROR */
 517 };
 518
 519 static int
 520 dfu_handle(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 521 {
 522         struct usb_gadget *gadget = f->config->cdev->gadget;
 523         struct usb_request *req = f->config->cdev->req;
 524         struct f_dfu *f_dfu = f->config->cdev->req->context;
 525         u16 len = le16_to_cpu(ctrl->wLength);
 526         u16 w_value = le16_to_cpu(ctrl->wValue);
 527         int value = 0;
 528         u8 req_type = ctrl->bRequestType & USB_TYPE_MASK;
 529
 530         debug("w_value: 0x%x len: 0x%x\n", w_value, len);
 531         debug("req_type: 0x%x ctrl->bRequest: 0x%x f_dfu->dfu_state: 0x%x\n",
 532                req_type, ctrl->bRequest, f_dfu->dfu_state);
 533
 534         if (req_type == USB_TYPE_STANDARD) {
 535                 if (ctrl->bRequest == USB_REQ_GET_DESCRIPTOR &&
 536                     (w_value >> 8) == DFU_DT_FUNC) {
 537                         value = min(len, (u16) sizeof(dfu_func));
 538                         memcpy(req->buf, &dfu_func, value);
 539                 }
 540         } else /* DFU specific request */
 541                 value = dfu_state[f_dfu->dfu_state] (f_dfu, ctrl, gadget, req);
 542
 543         if (value >= 0) {
 544                 req->length = value;
 545                 req->zero = value < len;
 546                 value = usb_ep_queue(gadget->ep0, req, 0);
 547                 if (value < 0) {
 548                         debug("ep_queue --> %d\n", value);
 549                         req->status = 0;
 550                 }
 551         }
 552
 553         return value;
 554 }
 555
 556 /*-------------------------------------------------------------------------*/
 557
 558 static int
 559 dfu_prepare_strings(struct f_dfu *f_dfu, int n)
 560 {
 561         struct dfu_entity *de = NULL;
 562         int i = 0;
 563
 564         f_dfu->strings = calloc(sizeof(struct usb_string), n + 1);
 565         if (!f_dfu->strings)
 566                 goto enomem;
 567
 568         for (i = 0; i < n; ++i) {
 569                 de = dfu_get_entity(i);
 570                 f_dfu->strings[i].s = de->name;
 571         }
 572
 573         f_dfu->strings[i].id = 0;
 574         f_dfu->strings[i].s = NULL;
 575
 576         return 0;
 577
 578 enomem:
 579         while (i)
 580                 f_dfu->strings[--i].s = NULL;
 581
 582         free(f_dfu->strings);
 583
 584         return -ENOMEM;
 585 }
 586
 587 static int dfu_prepare_function(struct f_dfu *f_dfu, int n)
 588 {
 589         struct usb_interface_descriptor *d;
 590         int i = 0;
 591
 592         f_dfu->function = calloc(sizeof(struct usb_descriptor_header *), n);
 593         if (!f_dfu->function)
 594                 goto enomem;
 595
 596         for (i = 0; i < n; ++i) {
 597                 d = calloc(sizeof(*d), 1);
 598                 if (!d)
 599                         goto enomem;
 600
 601                 d->bLength =            sizeof(*d);
 602                 d->bDescriptorType =    USB_DT_INTERFACE;
 603                 d->bAlternateSetting =  i;
 604                 d->bNumEndpoints =      0;
 605                 d->bInterfaceClass =    USB_CLASS_APP_SPEC;
 606                 d->bInterfaceSubClass = 1;
 607                 d->bInterfaceProtocol = 2;
 608
 609                 f_dfu->function[i] = (struct usb_descriptor_header *)d;
 610         }
 611         f_dfu->function[i] = NULL;
 612
 613         return 0;
 614
 615 enomem:
 616         while (i) {
 617                 free(f_dfu->function[--i]);
 618                 f_dfu->function[i] = NULL;
 619         }
 620         free(f_dfu->function);
 621
 622         return -ENOMEM;
 623 }
 624
 625 static int dfu_bind(struct usb_configuration *c, struct usb_function *f)
 626 {
 627         struct usb_composite_dev *cdev = c->cdev;
 628         struct f_dfu *f_dfu = func_to_dfu(f);
 629         int alt_num = dfu_get_alt_number();
 630         int rv, id, i;
 631
 632         id = usb_interface_id(c, f);
 633         if (id < 0)
 634                 return id;
 635         dfu_intf_runtime.bInterfaceNumber = id;
 636
 637         f_dfu->dfu_state = DFU_STATE_appIDLE;
 638         f_dfu->dfu_status = DFU_STATUS_OK;
 639
 640         rv = dfu_prepare_function(f_dfu, alt_num);
 641         if (rv)
 642                 goto error;
 643
 644         rv = dfu_prepare_strings(f_dfu, alt_num);
 645         if (rv)
 646                 goto error;
 647         for (i = 0; i < alt_num; i++) {
 648                 id = usb_string_id(cdev);
 649                 if (id < 0)
 650                         return id;
 651                 f_dfu->strings[i].id = id;
 652                 ((struct usb_interface_descriptor *)f_dfu->function[i])
 653                         ->iInterface = id;
 654         }
 655
 656         stringtab_dfu.strings = f_dfu->strings;
 657
 658         cdev->req->context = f_dfu;
 659
 660 error:
 661         return rv;
 662 }
 663
 664 static void dfu_unbind(struct usb_configuration *c, struct usb_function *f)
 665 {
 666         struct f_dfu *f_dfu = func_to_dfu(f);
 667         int alt_num = dfu_get_alt_number();
 668         int i;
 669
 670         if (f_dfu->strings) {
 671                 i = alt_num;
 672                 while (i)
 673                         f_dfu->strings[--i].s = NULL;
 674
 675                 free(f_dfu->strings);
 676         }
 677
 678         if (f_dfu->function) {
 679                 i = alt_num;
 680                 while (i) {
 681                         free(f_dfu->function[--i]);
 682                         f_dfu->function[i] = NULL;
 683                 }
 684                 free(f_dfu->function);
 685         }
 686
 687         free(f_dfu);
 688 }
 689
 690 static int dfu_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 691 {
 692         struct f_dfu *f_dfu = func_to_dfu(f);
 693
 694         debug("%s: intf:%d alt:%d\n", __func__, intf, alt);
 695
 696         f_dfu->altsetting = alt;
 697
 698         return 0;
 699 }
 700
 701 /* TODO: is this really what we need here? */
 702 static void dfu_disable(struct usb_function *f)
 703 {
 704         struct f_dfu *f_dfu = func_to_dfu(f);
 705         if (f_dfu->config == 0)
 706                 return;
 707
 708         debug("%s: reset config\n", __func__);
 709
 710         f_dfu->config = 0;
 711 }
 712
 713 static int dfu_bind_config(struct usb_configuration *c)
 714 {
 715         struct f_dfu *f_dfu;
 716         int status;
 717
 718         f_dfu = calloc(sizeof(*f_dfu), 1);
 719         if (!f_dfu)
 720                 return -ENOMEM;
 721         f_dfu->usb_function.name = "dfu";
 722         f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
 723         f_dfu->usb_function.bind = dfu_bind;
 724         f_dfu->usb_function.unbind = dfu_unbind;
 725         f_dfu->usb_function.set_alt = dfu_set_alt;
 726         f_dfu->usb_function.disable = dfu_disable;
 727         f_dfu->usb_function.strings = dfu_generic_strings,
 728         f_dfu->usb_function.setup = dfu_handle,
 729
 730         status = usb_add_function(c, &f_dfu->usb_function);
 731         if (status)
 732                 free(f_dfu);
 733
 734         return status;
 735 }
 736
 737 int dfu_add(struct usb_configuration *c)
 738 {
 739         int id;
 740
 741         id = usb_string_id(c->cdev);
 742         if (id < 0)
 743                 return id;
 744         strings_dfu_generic[0].id = id;
 745         dfu_intf_runtime.iInterface = id;
 746
 747         debug("%s: cdev: 0x%p gadget:0x%p gadget->ep0: 0x%p\n", __func__,
 748                c->cdev, c->cdev->gadget, c->cdev->gadget->ep0);
 749
 750         return dfu_bind_config(c);
 751 }