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  * Based on OpenMoko u-boot: drivers/usb/usbdfu.c
   9  * (C) 2007 by OpenMoko, Inc.
  10  * Author: Harald Welte <laforge@openmoko.org>
  11  *
  12  * based on existing SAM7DFU code from OpenPCD:
  13  * (C) Copyright 2006 by Harald Welte <hwelte at hmw-consulting.de>
  14  *
  15  * SPDX-License-Identifier:     GPL-2.0+
  16  */
  17
  18 #include <errno.h>
  19 #include <common.h>
  20 #include <malloc.h>
  21
  22 #include <linux/usb/ch9.h>
  23 #include <linux/usb/gadget.h>
  24 #include <linux/usb/composite.h>
  25
  26 #include <dfu.h>
  27 #include "f_dfu.h"
  28
  29 struct f_dfu {
  30         struct usb_function             usb_function;
  31
  32         struct usb_descriptor_header    **function;
  33         struct usb_string               *strings;
  34
  35         /* when configured, we have one config */
  36         u8                              config;
  37         u8                              altsetting;
  38         enum dfu_state                  dfu_state;
  39         unsigned int                    dfu_status;
  40
  41         /* Send/received block number is handy for data integrity check */
  42         int                             blk_seq_num;
  43         unsigned int                    poll_timeout;
  44 };
  45
  46 typedef int (*dfu_state_fn) (struct f_dfu *,
  47                              const struct usb_ctrlrequest *,
  48                              struct usb_gadget *,
  49                              struct usb_request *);
  50
  51 static inline struct f_dfu *func_to_dfu(struct usb_function *f)
  52 {
  53         return container_of(f, struct f_dfu, usb_function);
  54 }
  55
  56 static const struct dfu_function_descriptor dfu_func = {
  57         .bLength =              sizeof dfu_func,
  58         .bDescriptorType =      DFU_DT_FUNC,
  59         .bmAttributes =         DFU_BIT_WILL_DETACH |
  60                                 DFU_BIT_MANIFESTATION_TOLERANT |
  61                                 DFU_BIT_CAN_UPLOAD |
  62                                 DFU_BIT_CAN_DNLOAD,
  63         .wDetachTimeOut =       0,
  64         .wTransferSize =        DFU_USB_BUFSIZ,
  65         .bcdDFUVersion =        __constant_cpu_to_le16(0x0110),
  66 };
  67
  68 static struct usb_interface_descriptor dfu_intf_runtime = {
  69         .bLength =              sizeof dfu_intf_runtime,
  70         .bDescriptorType =      USB_DT_INTERFACE,
  71         .bNumEndpoints =        0,
  72         .bInterfaceClass =      USB_CLASS_APP_SPEC,
  73         .bInterfaceSubClass =   1,
  74         .bInterfaceProtocol =   1,
  75         /* .iInterface = DYNAMIC */
  76 };
  77
  78 static struct usb_descriptor_header *dfu_runtime_descs[] = {
  79         (struct usb_descriptor_header *) &dfu_intf_runtime,
  80         NULL,
  81 };
  82
  83 static const struct usb_qualifier_descriptor dev_qualifier = {
  84         .bLength =              sizeof dev_qualifier,
  85         .bDescriptorType =      USB_DT_DEVICE_QUALIFIER,
  86         .bcdUSB =               __constant_cpu_to_le16(0x0200),
  87         .bDeviceClass =         USB_CLASS_VENDOR_SPEC,
  88         .bNumConfigurations =   1,
  89 };
  90
  91 static const char dfu_name[] = "Device Firmware Upgrade";
  92
  93 /*
  94  * static strings, in UTF-8
  95  *
  96  * dfu_generic configuration
  97  */
  98 static struct usb_string strings_dfu_generic[] = {
  99         [0].s = dfu_name,
 100         {  }                    /* end of list */
 101 };
 102
 103 static struct usb_gadget_strings stringtab_dfu_generic = {
 104         .language       = 0x0409,       /* en-us */
 105         .strings        = strings_dfu_generic,
 106 };
 107
 108 static struct usb_gadget_strings *dfu_generic_strings[] = {
 109         &stringtab_dfu_generic,
 110         NULL,
 111 };
 112
 113 /*
 114  * usb_function specific
 115  */
 116 static struct usb_gadget_strings stringtab_dfu = {
 117         .language       = 0x0409,       /* en-us */
 118         /*
 119          * .strings
 120          *
 121          * assigned during initialization,
 122          * depends on number of flash entities
 123          *
 124          */
 125 };
 126
 127 static struct usb_gadget_strings *dfu_strings[] = {
 128         &stringtab_dfu,
 129         NULL,
 130 };
 131
 132 static void dfu_set_poll_timeout(struct dfu_status *dstat, unsigned int ms)
 133 {
 134         /*
 135          * The bwPollTimeout DFU_GETSTATUS request payload provides information
 136          * about minimum time, in milliseconds, that the host should wait before
 137          * sending a subsequent DFU_GETSTATUS request
 138          *
 139          * This permits the device to vary the delay depending on its need to
 140          * erase or program the memory
 141          *
 142          */
 143
 144         unsigned char *p = (unsigned char *)&ms;
 145
 146         if (!ms || (ms & ~DFU_POLL_TIMEOUT_MASK)) {
 147                 dstat->bwPollTimeout[0] = 0;
 148                 dstat->bwPollTimeout[1] = 0;
 149                 dstat->bwPollTimeout[2] = 0;
 150
 151                 return;
 152         }
 153
 154         dstat->bwPollTimeout[0] = *p++;
 155         dstat->bwPollTimeout[1] = *p++;
 156         dstat->bwPollTimeout[2] = *p;
 157 }
 158
 159 /*-------------------------------------------------------------------------*/
 160
 161 static void dnload_request_complete(struct usb_ep *ep, struct usb_request *req)
 162 {
 163         struct f_dfu *f_dfu = req->context;
 164
 165         dfu_write(dfu_get_entity(f_dfu->altsetting), req->buf,
 166                   req->length, f_dfu->blk_seq_num);
 167
 168         if (req->length == 0)
 169                 puts("DOWNLOAD ... OK\nCtrl+C to exit ...\n");
 170 }
 171
 172 static void handle_getstatus(struct usb_request *req)
 173 {
 174         struct dfu_status *dstat = (struct dfu_status *)req->buf;
 175         struct f_dfu *f_dfu = req->context;
 176
 177         switch (f_dfu->dfu_state) {
 178         case DFU_STATE_dfuDNLOAD_SYNC:
 179         case DFU_STATE_dfuDNBUSY:
 180                 f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_IDLE;
 181                 break;
 182         case DFU_STATE_dfuMANIFEST_SYNC:
 183                 break;
 184         default:
 185                 break;
 186         }
 187
 188         dfu_set_poll_timeout(dstat, 0);
 189
 190         if (f_dfu->poll_timeout)
 191                 if (!(f_dfu->blk_seq_num %
 192                       (dfu_get_buf_size() / DFU_USB_BUFSIZ)))
 193                         dfu_set_poll_timeout(dstat, f_dfu->poll_timeout);
 194
 195         /* send status response */
 196         dstat->bStatus = f_dfu->dfu_status;
 197         dstat->bState = f_dfu->dfu_state;
 198         dstat->iString = 0;
 199 }
 200
 201 static void handle_getstate(struct usb_request *req)
 202 {
 203         struct f_dfu *f_dfu = req->context;
 204
 205         ((u8 *)req->buf)[0] = f_dfu->dfu_state;
 206         req->actual = sizeof(u8);
 207 }
 208
 209 static inline void to_dfu_mode(struct f_dfu *f_dfu)
 210 {
 211         f_dfu->usb_function.strings = dfu_strings;
 212         f_dfu->usb_function.hs_descriptors = f_dfu->function;
 213         f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 214 }
 215
 216 static inline void to_runtime_mode(struct f_dfu *f_dfu)
 217 {
 218         f_dfu->usb_function.strings = NULL;
 219         f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
 220 }
 221
 222 static int handle_upload(struct usb_request *req, u16 len)
 223 {
 224         struct f_dfu *f_dfu = req->context;
 225
 226         return dfu_read(dfu_get_entity(f_dfu->altsetting), req->buf,
 227                         req->length, f_dfu->blk_seq_num);
 228 }
 229
 230 static int handle_dnload(struct usb_gadget *gadget, u16 len)
 231 {
 232         struct usb_composite_dev *cdev = get_gadget_data(gadget);
 233         struct usb_request *req = cdev->req;
 234         struct f_dfu *f_dfu = req->context;
 235
 236         if (len == 0)
 237                 f_dfu->dfu_state = DFU_STATE_dfuMANIFEST_SYNC;
 238
 239         req->complete = dnload_request_complete;
 240
 241         return len;
 242 }
 243
 244 /*-------------------------------------------------------------------------*/
 245 /* DFU state machine  */
 246 static int state_app_idle(struct f_dfu *f_dfu,
 247                           const struct usb_ctrlrequest *ctrl,
 248                           struct usb_gadget *gadget,
 249                           struct usb_request *req)
 250 {
 251         int value = 0;
 252
 253         switch (ctrl->bRequest) {
 254         case USB_REQ_DFU_GETSTATUS:
 255                 handle_getstatus(req);
 256                 value = RET_STAT_LEN;
 257                 break;
 258         case USB_REQ_DFU_GETSTATE:
 259                 handle_getstate(req);
 260                 break;
 261         case USB_REQ_DFU_DETACH:
 262                 f_dfu->dfu_state = DFU_STATE_appDETACH;
 263                 to_dfu_mode(f_dfu);
 264                 value = RET_ZLP;
 265                 break;
 266         default:
 267                 value = RET_STALL;
 268                 break;
 269         }
 270
 271         return value;
 272 }
 273
 274 static int state_app_detach(struct f_dfu *f_dfu,
 275                             const struct usb_ctrlrequest *ctrl,
 276                             struct usb_gadget *gadget,
 277                             struct usb_request *req)
 278 {
 279         int value = 0;
 280
 281         switch (ctrl->bRequest) {
 282         case USB_REQ_DFU_GETSTATUS:
 283                 handle_getstatus(req);
 284                 value = RET_STAT_LEN;
 285                 break;
 286         case USB_REQ_DFU_GETSTATE:
 287                 handle_getstate(req);
 288                 break;
 289         default:
 290                 f_dfu->dfu_state = DFU_STATE_appIDLE;
 291                 value = RET_STALL;
 292                 break;
 293         }
 294
 295         return value;
 296 }
 297
 298 static int state_dfu_idle(struct f_dfu *f_dfu,
 299                           const struct usb_ctrlrequest *ctrl,
 300                           struct usb_gadget *gadget,
 301                           struct usb_request *req)
 302 {
 303         u16 w_value = le16_to_cpu(ctrl->wValue);
 304         u16 len = le16_to_cpu(ctrl->wLength);
 305         int value = 0;
 306
 307         switch (ctrl->bRequest) {
 308         case USB_REQ_DFU_DNLOAD:
 309                 if (len == 0) {
 310                         f_dfu->dfu_state = DFU_STATE_dfuERROR;
 311                         value = RET_STALL;
 312                         break;
 313                 }
 314                 f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
 315                 f_dfu->blk_seq_num = w_value;
 316                 value = handle_dnload(gadget, len);
 317                 break;
 318         case USB_REQ_DFU_UPLOAD:
 319                 f_dfu->dfu_state = DFU_STATE_dfuUPLOAD_IDLE;
 320                 f_dfu->blk_seq_num = 0;
 321                 value = handle_upload(req, len);
 322                 break;
 323         case USB_REQ_DFU_ABORT:
 324                 /* no zlp? */
 325                 value = RET_ZLP;
 326                 break;
 327         case USB_REQ_DFU_GETSTATUS:
 328                 handle_getstatus(req);
 329                 value = RET_STAT_LEN;
 330                 break;
 331         case USB_REQ_DFU_GETSTATE:
 332                 handle_getstate(req);
 333                 break;
 334         case USB_REQ_DFU_DETACH:
 335                 /*
 336                  * Proprietary extension: 'detach' from idle mode and
 337                  * get back to runtime mode in case of USB Reset.  As
 338                  * much as I dislike this, we just can't use every USB
 339                  * bus reset to switch back to runtime mode, since at
 340                  * least the Linux USB stack likes to send a number of
 341                  * resets in a row :(
 342                  */
 343                 f_dfu->dfu_state =
 344                         DFU_STATE_dfuMANIFEST_WAIT_RST;
 345                 to_runtime_mode(f_dfu);
 346                 f_dfu->dfu_state = DFU_STATE_appIDLE;
 347
 348                 dfu_trigger_reset();
 349                 break;
 350         default:
 351                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 352                 value = RET_STALL;
 353                 break;
 354         }
 355
 356         return value;
 357 }
 358
 359 static int state_dfu_dnload_sync(struct f_dfu *f_dfu,
 360                                  const struct usb_ctrlrequest *ctrl,
 361                                  struct usb_gadget *gadget,
 362                                  struct usb_request *req)
 363 {
 364         int value = 0;
 365
 366         switch (ctrl->bRequest) {
 367         case USB_REQ_DFU_GETSTATUS:
 368                 handle_getstatus(req);
 369                 value = RET_STAT_LEN;
 370                 break;
 371         case USB_REQ_DFU_GETSTATE:
 372                 handle_getstate(req);
 373                 break;
 374         default:
 375                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 376                 value = RET_STALL;
 377                 break;
 378         }
 379
 380         return value;
 381 }
 382
 383 static int state_dfu_dnbusy(struct f_dfu *f_dfu,
 384                             const struct usb_ctrlrequest *ctrl,
 385                             struct usb_gadget *gadget,
 386                             struct usb_request *req)
 387 {
 388         int value = 0;
 389
 390         switch (ctrl->bRequest) {
 391         case USB_REQ_DFU_GETSTATUS:
 392                 handle_getstatus(req);
 393                 value = RET_STAT_LEN;
 394                 break;
 395         default:
 396                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 397                 value = RET_STALL;
 398                 break;
 399         }
 400
 401         return value;
 402 }
 403
 404 static int state_dfu_dnload_idle(struct f_dfu *f_dfu,
 405                                  const struct usb_ctrlrequest *ctrl,
 406                                  struct usb_gadget *gadget,
 407                                  struct usb_request *req)
 408 {
 409         u16 w_value = le16_to_cpu(ctrl->wValue);
 410         u16 len = le16_to_cpu(ctrl->wLength);
 411         int value = 0;
 412
 413         switch (ctrl->bRequest) {
 414         case USB_REQ_DFU_DNLOAD:
 415                 f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
 416                 f_dfu->blk_seq_num = w_value;
 417                 value = handle_dnload(gadget, len);
 418                 break;
 419         case USB_REQ_DFU_ABORT:
 420                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 421                 value = RET_ZLP;
 422                 break;
 423         case USB_REQ_DFU_GETSTATUS:
 424                 handle_getstatus(req);
 425                 value = RET_STAT_LEN;
 426                 break;
 427         case USB_REQ_DFU_GETSTATE:
 428                 handle_getstate(req);
 429                 break;
 430         default:
 431                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 432                 value = RET_STALL;
 433                 break;
 434         }
 435
 436         return value;
 437 }
 438
 439 static int state_dfu_manifest_sync(struct f_dfu *f_dfu,
 440                                    const struct usb_ctrlrequest *ctrl,
 441                                    struct usb_gadget *gadget,
 442                                    struct usb_request *req)
 443 {
 444         int value = 0;
 445
 446         switch (ctrl->bRequest) {
 447         case USB_REQ_DFU_GETSTATUS:
 448                 /* We're MainfestationTolerant */
 449                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 450                 handle_getstatus(req);
 451                 f_dfu->blk_seq_num = 0;
 452                 value = RET_STAT_LEN;
 453                 break;
 454         case USB_REQ_DFU_GETSTATE:
 455                 handle_getstate(req);
 456                 break;
 457         default:
 458                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 459                 value = RET_STALL;
 460                 break;
 461         }
 462
 463         return value;
 464 }
 465
 466 static int state_dfu_upload_idle(struct f_dfu *f_dfu,
 467                                  const struct usb_ctrlrequest *ctrl,
 468                                  struct usb_gadget *gadget,
 469                                  struct usb_request *req)
 470 {
 471         u16 w_value = le16_to_cpu(ctrl->wValue);
 472         u16 len = le16_to_cpu(ctrl->wLength);
 473         int value = 0;
 474
 475         switch (ctrl->bRequest) {
 476         case USB_REQ_DFU_UPLOAD:
 477                 /* state transition if less data then requested */
 478                 f_dfu->blk_seq_num = w_value;
 479                 value = handle_upload(req, len);
 480                 if (value >= 0 && value < len)
 481                         f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 482                 break;
 483         case USB_REQ_DFU_ABORT:
 484                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 485                 /* no zlp? */
 486                 value = RET_ZLP;
 487                 break;
 488         case USB_REQ_DFU_GETSTATUS:
 489                 handle_getstatus(req);
 490                 value = RET_STAT_LEN;
 491                 break;
 492         case USB_REQ_DFU_GETSTATE:
 493                 handle_getstate(req);
 494                 break;
 495         default:
 496                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 497                 value = RET_STALL;
 498                 break;
 499         }
 500
 501         return value;
 502 }
 503
 504 static int state_dfu_error(struct f_dfu *f_dfu,
 505                                  const struct usb_ctrlrequest *ctrl,
 506                                  struct usb_gadget *gadget,
 507                                  struct usb_request *req)
 508 {
 509         int value = 0;
 510
 511         switch (ctrl->bRequest) {
 512         case USB_REQ_DFU_GETSTATUS:
 513                 handle_getstatus(req);
 514                 value = RET_STAT_LEN;
 515                 break;
 516         case USB_REQ_DFU_GETSTATE:
 517                 handle_getstate(req);
 518                 break;
 519         case USB_REQ_DFU_CLRSTATUS:
 520                 f_dfu->dfu_state = DFU_STATE_dfuIDLE;
 521                 f_dfu->dfu_status = DFU_STATUS_OK;
 522                 /* no zlp? */
 523                 value = RET_ZLP;
 524                 break;
 525         default:
 526                 f_dfu->dfu_state = DFU_STATE_dfuERROR;
 527                 value = RET_STALL;
 528                 break;
 529         }
 530
 531         return value;
 532 }
 533
 534 static dfu_state_fn dfu_state[] = {
 535         state_app_idle,          /* DFU_STATE_appIDLE */
 536         state_app_detach,        /* DFU_STATE_appDETACH */
 537         state_dfu_idle,          /* DFU_STATE_dfuIDLE */
 538         state_dfu_dnload_sync,   /* DFU_STATE_dfuDNLOAD_SYNC */
 539         state_dfu_dnbusy,        /* DFU_STATE_dfuDNBUSY */
 540         state_dfu_dnload_idle,   /* DFU_STATE_dfuDNLOAD_IDLE */
 541         state_dfu_manifest_sync, /* DFU_STATE_dfuMANIFEST_SYNC */
 542         NULL,                    /* DFU_STATE_dfuMANIFEST */
 543         NULL,                    /* DFU_STATE_dfuMANIFEST_WAIT_RST */
 544         state_dfu_upload_idle,   /* DFU_STATE_dfuUPLOAD_IDLE */
 545         state_dfu_error          /* DFU_STATE_dfuERROR */
 546 };
 547
 548 static int
 549 dfu_handle(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 550 {
 551         struct usb_gadget *gadget = f->config->cdev->gadget;
 552         struct usb_request *req = f->config->cdev->req;
 553         struct f_dfu *f_dfu = f->config->cdev->req->context;
 554         u16 len = le16_to_cpu(ctrl->wLength);
 555         u16 w_value = le16_to_cpu(ctrl->wValue);
 556         int value = 0;
 557         u8 req_type = ctrl->bRequestType & USB_TYPE_MASK;
 558
 559         debug("w_value: 0x%x len: 0x%x\n", w_value, len);
 560         debug("req_type: 0x%x ctrl->bRequest: 0x%x f_dfu->dfu_state: 0x%x\n",
 561                req_type, ctrl->bRequest, f_dfu->dfu_state);
 562
 563         if (req_type == USB_TYPE_STANDARD) {
 564                 if (ctrl->bRequest == USB_REQ_GET_DESCRIPTOR &&
 565                     (w_value >> 8) == DFU_DT_FUNC) {
 566                         value = min(len, (u16) sizeof(dfu_func));
 567                         memcpy(req->buf, &dfu_func, value);
 568                 }
 569         } else /* DFU specific request */
 570                 value = dfu_state[f_dfu->dfu_state] (f_dfu, ctrl, gadget, req);
 571
 572         if (value >= 0) {
 573                 req->length = value;
 574                 req->zero = value < len;
 575                 value = usb_ep_queue(gadget->ep0, req, 0);
 576                 if (value < 0) {
 577                         debug("ep_queue --> %d\n", value);
 578                         req->status = 0;
 579                 }
 580         }
 581
 582         return value;
 583 }
 584
 585 /*-------------------------------------------------------------------------*/
 586
 587 static int
 588 dfu_prepare_strings(struct f_dfu *f_dfu, int n)
 589 {
 590         struct dfu_entity *de = NULL;
 591         int i = 0;
 592
 593         f_dfu->strings = calloc(sizeof(struct usb_string), n + 1);
 594         if (!f_dfu->strings)
 595                 goto enomem;
 596
 597         for (i = 0; i < n; ++i) {
 598                 de = dfu_get_entity(i);
 599                 f_dfu->strings[i].s = de->name;
 600         }
 601
 602         f_dfu->strings[i].id = 0;
 603         f_dfu->strings[i].s = NULL;
 604
 605         return 0;
 606
 607 enomem:
 608         while (i)
 609                 f_dfu->strings[--i].s = NULL;
 610
 611         free(f_dfu->strings);
 612
 613         return -ENOMEM;
 614 }
 615
 616 static int dfu_prepare_function(struct f_dfu *f_dfu, int n)
 617 {
 618         struct usb_interface_descriptor *d;
 619         int i = 0;
 620
 621         f_dfu->function = calloc(sizeof(struct usb_descriptor_header *), n + 1);
 622         if (!f_dfu->function)
 623                 goto enomem;
 624
 625         for (i = 0; i < n; ++i) {
 626                 d = calloc(sizeof(*d), 1);
 627                 if (!d)
 628                         goto enomem;
 629
 630                 d->bLength =            sizeof(*d);
 631                 d->bDescriptorType =    USB_DT_INTERFACE;
 632                 d->bAlternateSetting =  i;
 633                 d->bNumEndpoints =      0;
 634                 d->bInterfaceClass =    USB_CLASS_APP_SPEC;
 635                 d->bInterfaceSubClass = 1;
 636                 d->bInterfaceProtocol = 2;
 637
 638                 f_dfu->function[i] = (struct usb_descriptor_header *)d;
 639         }
 640         f_dfu->function[i] = NULL;
 641
 642         return 0;
 643
 644 enomem:
 645         while (i) {
 646                 free(f_dfu->function[--i]);
 647                 f_dfu->function[i] = NULL;
 648         }
 649         free(f_dfu->function);
 650
 651         return -ENOMEM;
 652 }
 653
 654 static int dfu_bind(struct usb_configuration *c, struct usb_function *f)
 655 {
 656         struct usb_composite_dev *cdev = c->cdev;
 657         struct f_dfu *f_dfu = func_to_dfu(f);
 658         int alt_num = dfu_get_alt_number();
 659         int rv, id, i;
 660
 661         id = usb_interface_id(c, f);
 662         if (id < 0)
 663                 return id;
 664         dfu_intf_runtime.bInterfaceNumber = id;
 665
 666         f_dfu->dfu_state = DFU_STATE_appIDLE;
 667         f_dfu->dfu_status = DFU_STATUS_OK;
 668
 669         rv = dfu_prepare_function(f_dfu, alt_num);
 670         if (rv)
 671                 goto error;
 672
 673         rv = dfu_prepare_strings(f_dfu, alt_num);
 674         if (rv)
 675                 goto error;
 676         for (i = 0; i < alt_num; i++) {
 677                 id = usb_string_id(cdev);
 678                 if (id < 0)
 679                         return id;
 680                 f_dfu->strings[i].id = id;
 681                 ((struct usb_interface_descriptor *)f_dfu->function[i])
 682                         ->iInterface = id;
 683         }
 684
 685         to_dfu_mode(f_dfu);
 686
 687         stringtab_dfu.strings = f_dfu->strings;
 688
 689         cdev->req->context = f_dfu;
 690
 691 error:
 692         return rv;
 693 }
 694
 695 static void dfu_unbind(struct usb_configuration *c, struct usb_function *f)
 696 {
 697         struct f_dfu *f_dfu = func_to_dfu(f);
 698         int alt_num = dfu_get_alt_number();
 699         int i;
 700
 701         if (f_dfu->strings) {
 702                 i = alt_num;
 703                 while (i)
 704                         f_dfu->strings[--i].s = NULL;
 705
 706                 free(f_dfu->strings);
 707         }
 708
 709         if (f_dfu->function) {
 710                 i = alt_num;
 711                 while (i) {
 712                         free(f_dfu->function[--i]);
 713                         f_dfu->function[i] = NULL;
 714                 }
 715                 free(f_dfu->function);
 716         }
 717
 718         free(f_dfu);
 719 }
 720
 721 static int dfu_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 722 {
 723         struct f_dfu *f_dfu = func_to_dfu(f);
 724
 725         debug("%s: intf:%d alt:%d\n", __func__, intf, alt);
 726
 727         f_dfu->altsetting = alt;
 728
 729         return 0;
 730 }
 731
 732 /* TODO: is this really what we need here? */
 733 static void dfu_disable(struct usb_function *f)
 734 {
 735         struct f_dfu *f_dfu = func_to_dfu(f);
 736         if (f_dfu->config == 0)
 737                 return;
 738
 739         debug("%s: reset config\n", __func__);
 740
 741         f_dfu->config = 0;
 742 }
 743
 744 static int dfu_bind_config(struct usb_configuration *c)
 745 {
 746         struct f_dfu *f_dfu;
 747         int status;
 748
 749         f_dfu = calloc(sizeof(*f_dfu), 1);
 750         if (!f_dfu)
 751                 return -ENOMEM;
 752         f_dfu->usb_function.name = "dfu";
 753         f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
 754         f_dfu->usb_function.bind = dfu_bind;
 755         f_dfu->usb_function.unbind = dfu_unbind;
 756         f_dfu->usb_function.set_alt = dfu_set_alt;
 757         f_dfu->usb_function.disable = dfu_disable;
 758         f_dfu->usb_function.strings = dfu_generic_strings;
 759         f_dfu->usb_function.setup = dfu_handle;
 760         f_dfu->poll_timeout = DFU_DEFAULT_POLL_TIMEOUT;
 761
 762         status = usb_add_function(c, &f_dfu->usb_function);
 763         if (status)
 764                 free(f_dfu);
 765
 766         return status;
 767 }
 768
 769 int dfu_add(struct usb_configuration *c)
 770 {
 771         int id;
 772
 773         id = usb_string_id(c->cdev);
 774         if (id < 0)
 775                 return id;
 776         strings_dfu_generic[0].id = id;
 777         dfu_intf_runtime.iInterface = id;
 778
 779         debug("%s: cdev: 0x%p gadget:0x%p gadget->ep0: 0x%p\n", __func__,
 780                c->cdev, c->cdev->gadget, c->cdev->gadget->ep0);
 781
 782         return dfu_bind_config(c);
 783 }