bootloader/main-pp.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2006 by Barry Wardell
  11  *
  12  * Based on Rockbox iriver bootloader by Linus Nielsen Feltzing
  13  * and the ipodlinux bootloader by Daniel Palffy and Bernard Leach
  14  *
  15  * All files in this archive are subject to the GNU General Public License.
  16  * See the file COPYING in the source tree root for full license agreement.
  17  *
  18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  19  * KIND, either express or implied.
  20  *
  21  ****************************************************************************/
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include "common.h"
  25 #include "cpu.h"
  26 #include "file.h"
  27 #include "system.h"
  28 #include "kernel.h"
  29 #include "lcd.h"
  30 #include "font.h"
  31 #include "ata.h"
  32 #include "button.h"
  33 #include "disk.h"
  34 #include "crc32-mi4.h"
  35 #include <string.h>
  36 #if defined(SANSA_E200)
  37 #include "i2c.h"
  38 #include "backlight-target.h"
  39 #endif
  40 #if defined(SANSA_E200) || defined(SANSA_C200)
  41 #include "usb.h"
  42 #include "arcotg_udc.h"
  43 #endif
  44
  45
  46 /* Button definitions */
  47 #if CONFIG_KEYPAD == IRIVER_H10_PAD
  48 #define BOOTLOADER_BOOT_OF      BUTTON_LEFT
  49
  50 #elif CONFIG_KEYPAD == SANSA_E200_PAD
  51 #define BOOTLOADER_BOOT_OF      BUTTON_LEFT
  52
  53 #elif CONFIG_KEYPAD == SANSA_C200_PAD
  54 #define BOOTLOADER_BOOT_OF      BUTTON_LEFT
  55
  56 #endif
  57
  58 /* Maximum allowed firmware image size. 10MB is more than enough */
  59 #define MAX_LOADSIZE (10*1024*1024)
  60
  61 /* A buffer to load the original firmware or Rockbox into */
  62 unsigned char *loadbuffer = (unsigned char *)DRAM_START;
  63
  64 /* Bootloader version */
  65 char version[] = APPSVERSION;
  66
  67 /* Locations and sizes in hidden partition on Sansa */
  68 #if defined(SANSA_E200) || defined(SANSA_C200)
  69 #define PPMI_SECTOR_OFFSET  1024
  70 #define PPMI_SECTORS        1
  71 #define MI4_HEADER_SECTORS  1
  72 #define NUM_PARTITIONS      2
  73
  74 #else
  75 #define NUM_PARTITIONS      1
  76
  77 #endif
  78
  79 #define MI4_HEADER_SIZE     0x200
  80
  81 /* mi4 header structure */
  82 struct mi4header_t {
  83     unsigned char magic[4];
  84     uint32_t version;
  85     uint32_t length;
  86     uint32_t crc32;
  87     uint32_t enctype;
  88     uint32_t mi4size;
  89     uint32_t plaintext;
  90     uint32_t dsa_key[10];
  91     uint32_t pad[109];
  92     unsigned char type[4];
  93     unsigned char model[4];
  94 };
  95
  96 /* PPMI header structure */
  97 struct ppmi_header_t {
  98     unsigned char magic[4];
  99     uint32_t length;
 100     uint32_t pad[126];
 101 };
 102
 103 inline unsigned int le2int(unsigned char* buf)
 104 {
 105    int32_t res = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 106
 107    return res;
 108 }
 109
 110 inline void int2le(unsigned int val, unsigned char* addr)
 111 {
 112     addr[0] = val & 0xFF;
 113     addr[1] = (val >> 8) & 0xff;
 114     addr[2] = (val >> 16) & 0xff;
 115     addr[3] = (val >> 24) & 0xff;
 116 }
 117
 118 struct tea_key {
 119   const char * name;
 120   uint32_t     key[4];
 121 };
 122
 123 #define NUM_KEYS (sizeof(tea_keytable)/sizeof(tea_keytable[0]))
 124 struct tea_key tea_keytable[] = {
 125   { "default" ,          { 0x20d36cc0, 0x10e8c07d, 0xc0e7dcaa, 0x107eb080 } },
 126   { "sansa",             { 0xe494e96e, 0x3ee32966, 0x6f48512b, 0xa93fbb42 } },
 127   { "sansa_gh",          { 0xd7b10538, 0xc662945b, 0x1b3fce68, 0xf389c0e6 } },
 128   { "sansa_103",         { 0x1d29ddc0, 0x2579c2cd, 0xce339e1a, 0x75465dfe } },
 129   { "rhapsody",          { 0x7aa9c8dc, 0xbed0a82a, 0x16204cc7, 0x5904ef38 } },
 130   { "p610",              { 0x950e83dc, 0xec4907f9, 0x023734b9, 0x10cfb7c7 } },
 131   { "p640",              { 0x220c5f23, 0xd04df68e, 0x431b5e25, 0x4dcc1fa1 } },
 132   { "virgin",            { 0xe83c29a1, 0x04862973, 0xa9b3f0d4, 0x38be2a9c } },
 133   { "20gc_eng",          { 0x0240772c, 0x6f3329b5, 0x3ec9a6c5, 0xb0c9e493 } },
 134   { "20gc_fre",          { 0xbede8817, 0xb23bfe4f, 0x80aa682d, 0xd13f598c } },
 135   { "elio_p722",         { 0x6af3b9f8, 0x777483f5, 0xae8181cc, 0xfa6d8a84 } },
 136   { "c200",              { 0xbf2d06fa, 0xf0e23d59, 0x29738132, 0xe2d04ca7 } },
 137   { "c200_103",          { 0x2a7968de, 0x15127979, 0x142e60a7, 0xe49c1893 } },
 138   { "c200_106",          { 0xa913d139, 0xf842f398, 0x3e03f1a6, 0x060ee012 } },
 139 };
 140
 141 /*
 142
 143 tea_decrypt() from http://en.wikipedia.org/wiki/Tiny_Encryption_Algorithm
 144
 145 "Following is an adaptation of the reference encryption and decryption
 146 routines in C, released into the public domain by David Wheeler and
 147 Roger Needham:"
 148
 149 */
 150
 151 /* NOTE: The mi4 version of TEA uses a different initial value to sum compared
 152          to the reference implementation and the main loop is 8 iterations, not
 153          32.
 154 */
 155
 156 static void tea_decrypt(uint32_t* v0, uint32_t* v1, uint32_t* k) {
 157     uint32_t sum=0xF1BBCDC8, i;                    /* set up */
 158     uint32_t delta=0x9E3779B9;                     /* a key schedule constant */
 159     uint32_t k0=k[0], k1=k[1], k2=k[2], k3=k[3];   /* cache key */
 160     for(i=0; i<8; i++) {                               /* basic cycle start */
 161         *v1 -= ((*v0<<4) + k2) ^ (*v0 + sum) ^ ((*v0>>5) + k3);
 162         *v0 -= ((*v1<<4) + k0) ^ (*v1 + sum) ^ ((*v1>>5) + k1);
 163         sum -= delta;                                   /* end cycle */
 164     }
 165 }
 166
 167 /* mi4 files are encrypted in 64-bit blocks (two little-endian 32-bit
 168    integers) and the key is incremented after each block
 169  */
 170
 171 static void tea_decrypt_buf(unsigned char* src, unsigned char* dest, size_t n, uint32_t * key)
 172 {
 173     uint32_t v0, v1;
 174     unsigned int i;
 175
 176     for (i = 0; i < (n / 8); i++) {
 177         v0 = le2int(src);
 178         v1 = le2int(src+4);
 179
 180         tea_decrypt(&v0, &v1, key);
 181
 182         int2le(v0, dest);
 183         int2le(v1, dest+4);
 184
 185         src += 8;
 186         dest += 8;
 187
 188         /* Now increment the key */
 189         key[0]++;
 190         if (key[0]==0) {
 191             key[1]++;
 192             if (key[1]==0) {
 193                 key[2]++;
 194                 if (key[2]==0) {
 195                     key[3]++;
 196                 }
 197             }
 198         }
 199     }
 200 }
 201
 202 static inline bool tea_test_key(unsigned char magic_enc[8], uint32_t * key, int unaligned)
 203 {
 204     unsigned char magic_dec[8];
 205     tea_decrypt_buf(magic_enc, magic_dec, 8, key);
 206
 207     return (le2int(&magic_dec[4*unaligned]) == 0xaa55aa55);
 208 }
 209
 210 static int tea_find_key(struct mi4header_t *mi4header, int fd)
 211 {
 212     unsigned int i;
 213     int rc;
 214     unsigned int j;
 215     uint32_t key[4];
 216     unsigned char magic_enc[8];
 217     int key_found = -1;
 218     unsigned int magic_location = mi4header->length-4;
 219     int unaligned = 0;
 220
 221     if ( (magic_location % 8) != 0 )
 222     {
 223         unaligned = 1;
 224         magic_location -= 4;
 225     }
 226
 227     /* Load encrypted magic 0xaa55aa55 to check key */
 228     lseek(fd, MI4_HEADER_SIZE + magic_location, SEEK_SET);
 229     rc = read(fd, magic_enc, 8);
 230     if(rc < 8 )
 231         return EREAD_IMAGE_FAILED;
 232
 233     printf("Searching for key:");
 234
 235     for (i=0; i < NUM_KEYS && (key_found<0) ; i++) {
 236         key[0] = tea_keytable[i].key[0];
 237         key[1] = tea_keytable[i].key[1];
 238         key[2] = tea_keytable[i].key[2];
 239         key[3] = tea_keytable[i].key[3];
 240
 241         /* Now increment the key */
 242         for(j=0; j<((magic_location-mi4header->plaintext)/8); j++){
 243             key[0]++;
 244             if (key[0]==0) {
 245                 key[1]++;
 246                 if (key[1]==0) {
 247                     key[2]++;
 248                     if (key[2]==0) {
 249                         key[3]++;
 250                     }
 251                 }
 252             }
 253         }
 254
 255         if (tea_test_key(magic_enc,key,unaligned))
 256         {
 257             key_found = i;
 258             printf("%s...found", tea_keytable[i].name);
 259         } else {
 260            /* printf("%s...failed", tea_keytable[i].name); */
 261         }
 262     }
 263
 264     return key_found;
 265 }
 266
 267
 268 /* Load mi4 format firmware image */
 269 int load_mi4(unsigned char* buf, char* firmware, unsigned int buffer_size)
 270 {
 271     int fd;
 272     struct mi4header_t mi4header;
 273     int rc;
 274     unsigned long sum;
 275     char filename[MAX_PATH];
 276
 277     snprintf(filename,sizeof(filename),"/.rockbox/%s",firmware);
 278     fd = open(filename, O_RDONLY);
 279     if(fd < 0)
 280     {
 281         snprintf(filename,sizeof(filename),"/%s",firmware);
 282         fd = open(filename, O_RDONLY);
 283         if(fd < 0)
 284             return EFILE_NOT_FOUND;
 285     }
 286
 287     read(fd, &mi4header, MI4_HEADER_SIZE);
 288
 289     /* MI4 file size */
 290     printf("mi4 size: %x", mi4header.mi4size);
 291
 292     if ((mi4header.mi4size-MI4_HEADER_SIZE) > buffer_size)
 293         return EFILE_TOO_BIG;
 294
 295     /* CRC32 */
 296     printf("CRC32: %x", mi4header.crc32);
 297
 298     /* Rockbox model id */
 299     printf("Model id: %.4s", mi4header.model);
 300
 301     /* Read binary type (RBOS, RBBL) */
 302     printf("Binary type: %.4s", mi4header.type);
 303
 304     /* Load firmware file */
 305     lseek(fd, MI4_HEADER_SIZE, SEEK_SET);
 306     rc = read(fd, buf, mi4header.mi4size-MI4_HEADER_SIZE);
 307     if(rc < (int)mi4header.mi4size-MI4_HEADER_SIZE)
 308         return EREAD_IMAGE_FAILED;
 309
 310     /* Check CRC32 to see if we have a valid file */
 311     sum = chksum_crc32 (buf, mi4header.mi4size - MI4_HEADER_SIZE);
 312
 313     printf("Calculated CRC32: %x", sum);
 314
 315     if(sum != mi4header.crc32)
 316         return EBAD_CHKSUM;
 317
 318     if( (mi4header.plaintext + MI4_HEADER_SIZE) != mi4header.mi4size)
 319     {
 320         /* Load encrypted firmware */
 321         int key_index = tea_find_key(&mi4header, fd);
 322
 323         if (key_index < 0)
 324             return EINVALID_FORMAT;
 325
 326         /* Plaintext part is already loaded */
 327         buf += mi4header.plaintext;
 328
 329         /* Decrypt in-place */
 330         tea_decrypt_buf(buf, buf,
 331                         mi4header.mi4size-(mi4header.plaintext+MI4_HEADER_SIZE),
 332                         tea_keytable[key_index].key);
 333
 334         printf("%s key used", tea_keytable[key_index].name);
 335
 336         /* Check decryption was successfull */
 337         if(le2int(&buf[mi4header.length-mi4header.plaintext-4]) != 0xaa55aa55)
 338         {
 339             return EREAD_IMAGE_FAILED;
 340         }
 341     }
 342
 343     return EOK;
 344 }
 345
 346 #if defined(SANSA_E200) || defined(SANSA_C200)
 347 #ifdef SANSA_E200
 348 struct OFDB_info {
 349     char *version;
 350     int version_length;
 351     int sector;
 352     int offset;
 353 } OFDatabaseOffsets[] = {
 354     { "PP5022AF-05.51-S301-01.11-S301.01.11A-D", 39, 0x3c08, 0xe1 },
 355     { "PP5022AF-05.51-S301-00.12-S301.00.12E-D", 39, 0x3c5c, 0x2 },
 356     { "PP5022AF-05.51-S301-00.12-S301.00.12A-D", 39, 0x3c08, 0xe1 },
 357 };
 358 #else /* SANSA_C200 */
 359 /* TODO: need to determine these for the c200 */
 360 struct OFDB_info {
 361     char *version;
 362     int version_length;
 363     int sector;
 364     int offset;
 365 } OFDatabaseOffsets[] = {
 366     { "PP5022AF-05.51-S301-01.11-S301.01.11A-D", 39, 0x3c08, 0xe1 },
 367 };
 368 #endif
 369
 370 /* Load mi4 firmware from a hidden disk partition */
 371 int load_mi4_part(unsigned char* buf, struct partinfo* pinfo,
 372                   unsigned int buffer_size, bool disable_rebuild)
 373 {
 374     struct mi4header_t mi4header;
 375     struct ppmi_header_t ppmi_header;
 376     unsigned long sum;
 377
 378     /* Read header to find out how long the mi4 file is. */
 379     ata_read_sectors(IF_MV2(0,) pinfo->start + PPMI_SECTOR_OFFSET,
 380                             PPMI_SECTORS, &ppmi_header);
 381
 382     /* The first four characters at 0x80000 (sector 1024) should be PPMI*/
 383     if( memcmp(ppmi_header.magic, "PPMI", 4) )
 384         return EFILE_NOT_FOUND;
 385
 386     printf("BL mi4 size: %x", ppmi_header.length);
 387
 388     /* Read mi4 header of the OF */
 389     ata_read_sectors(IF_MV2(0,) pinfo->start + PPMI_SECTOR_OFFSET + PPMI_SECTORS
 390                        + (ppmi_header.length/512), MI4_HEADER_SECTORS, &mi4header);
 391
 392     /* We don't support encrypted mi4 files yet */
 393     if( (mi4header.plaintext) != (mi4header.mi4size-MI4_HEADER_SIZE))
 394         return EINVALID_FORMAT;
 395
 396     /* MI4 file size */
 397     printf("OF mi4 size: %x", mi4header.mi4size);
 398
 399     if ((mi4header.mi4size-MI4_HEADER_SIZE) > buffer_size)
 400         return EFILE_TOO_BIG;
 401
 402     /* CRC32 */
 403     printf("CRC32: %x", mi4header.crc32);
 404
 405     /* Rockbox model id */
 406     printf("Model id: %.4s", mi4header.model);
 407
 408     /* Read binary type (RBOS, RBBL) */
 409     printf("Binary type: %.4s", mi4header.type);
 410
 411     /* Load firmware */
 412     ata_read_sectors(IF_MV2(0,) pinfo->start + PPMI_SECTOR_OFFSET + PPMI_SECTORS
 413                         + (ppmi_header.length/512) + MI4_HEADER_SECTORS,
 414                         (mi4header.mi4size-MI4_HEADER_SIZE)/512, buf);
 415
 416     /* Check CRC32 to see if we have a valid file */
 417     sum = chksum_crc32 (buf,mi4header.mi4size-MI4_HEADER_SIZE);
 418
 419     printf("Calculated CRC32: %x", sum);
 420
 421     if(sum != mi4header.crc32)
 422         return EBAD_CHKSUM;
 423
 424     if (disable_rebuild)
 425     {
 426         char block[512];
 427         int  sector = 0, offset = 0;
 428         unsigned int i;
 429         /* check which known version we have */
 430         /* These are taken from the PPPS section, 0x00780240 */
 431         ata_read_sectors(IF_MV2(0,) pinfo->start + 0x3C01, 1, block);
 432         for (i=0; i<sizeof(OFDatabaseOffsets)/sizeof(*OFDatabaseOffsets); i++)
 433         {
 434             if (!memcmp(&block[0x40], OFDatabaseOffsets[i].version,
 435                                       OFDatabaseOffsets[i].version_length))
 436             {
 437                 sector = pinfo->start + OFDatabaseOffsets[i].sector;
 438                 offset  = OFDatabaseOffsets[i].offset;
 439                 break;
 440             }
 441         }
 442         if (sector && offset)
 443         {
 444             ata_read_sectors(IF_MV2(0,) sector, 1, block);
 445             block[offset] = 0;
 446             ata_write_sectors(IF_MV2(0,) sector, 1, block);
 447         }
 448     }
 449     return EOK;
 450 }
 451 #endif
 452
 453 void* main(void)
 454 {
 455     int i;
 456     int btn;
 457     int rc;
 458     int num_partitions;
 459     struct partinfo* pinfo;
 460 #if defined(SANSA_E200) || defined(SANSA_C200)
 461     int usb_retry = 0;
 462     bool usb = false;
 463 #else
 464     char buf[256];
 465     unsigned short* identify_info;
 466 #endif
 467
 468     chksum_crc32gentab ();
 469
 470     system_init();
 471     kernel_init();
 472     lcd_init();
 473     font_init();
 474     button_init();
 475 #if defined(SANSA_E200)
 476     i2c_init();
 477     __backlight_on();
 478 #endif
 479
 480     lcd_set_foreground(LCD_WHITE);
 481     lcd_set_background(LCD_BLACK);
 482     lcd_clear_display();
 483
 484     btn = button_read_device();
 485 #if defined(SANSA_E200) || defined(SANSA_C200)
 486     usb_init();
 487     while ((UDC_OTGSC&0x800) && usb_retry < 5 && !usb)
 488     {
 489         usb_retry++;
 490         sleep(HZ/4);
 491         usb = (usb_detect() == USB_INSERTED);
 492     }
 493     if (usb)
 494         btn |= BOOTLOADER_BOOT_OF;
 495 #endif
 496     /* Enable bootloader messages if any button is pressed */
 497     if (btn)
 498         verbose = true;
 499
 500     lcd_setfont(FONT_SYSFIXED);
 501
 502     printf("Rockbox boot loader");
 503     printf("Version: %s", version);
 504     printf(MODEL_NAME);
 505
 506     i=ata_init();
 507 #if !defined(SANSA_E200) && !defined(SANSA_C200)
 508     if (i==0) {
 509         identify_info=ata_get_identify();
 510         /* Show model */
 511         for (i=0; i < 20; i++) {
 512             ((unsigned short*)buf)[i]=htobe16(identify_info[i+27]);
 513         }
 514         buf[40]=0;
 515         for (i=39; i && buf[i]==' '; i--) {
 516             buf[i]=0;
 517         }
 518         printf(buf);
 519     } else {
 520         error(EATA, i);
 521     }
 522 #endif
 523
 524     disk_init(IF_MV(0));
 525     num_partitions = disk_mount_all();
 526     if (num_partitions<=0)
 527     {
 528         error(EDISK,num_partitions);
 529     }
 530
 531     /* Just list the first 2 partitions since we don't have any devices yet
 532        that have more than that */
 533     for(i=0; i<NUM_PARTITIONS; i++)
 534     {
 535         pinfo = disk_partinfo(i);
 536         printf("Partition %d: 0x%02x %ld MB",
 537                 i, pinfo->type, pinfo->size / 2048);
 538     }
 539
 540     if(btn & BOOTLOADER_BOOT_OF)
 541     {
 542         /* Load original mi4 firmware in to a memory buffer called loadbuffer.
 543            The rest of the loading is done in crt0.S.
 544            1) First try reading from the hidden partition (on Sansa only).
 545            2) Next try a decrypted mi4 file in /System/OF.mi4
 546            3) Finally, try a raw firmware binary in /System/OF.mi4. It should be
 547               a mi4 firmware decrypted and header stripped using mi4code.
 548         */
 549         printf("Loading original firmware...");
 550
 551 #if defined(SANSA_E200) || defined(SANSA_C200)
 552         /* First try a (hidden) firmware partition */
 553         printf("Trying firmware partition");
 554         pinfo = disk_partinfo(1);
 555         if(pinfo->type == PARTITION_TYPE_OS2_HIDDEN_C_DRIVE)
 556         {
 557             rc = load_mi4_part(loadbuffer, pinfo, MAX_LOADSIZE, usb);
 558             if (rc < EOK) {
 559                 printf("Can't load from partition");
 560                 printf(strerror(rc));
 561             } else {
 562                 return (void*)loadbuffer;
 563             }
 564         } else {
 565             printf("No hidden partition found.");
 566         }
 567 #endif
 568
 569         printf("Trying /System/OF.mi4");
 570         rc=load_mi4(loadbuffer, "/System/OF.mi4", MAX_LOADSIZE);
 571         if (rc < EOK) {
 572             printf("Can't load /System/OF.mi4");
 573             printf(strerror(rc));
 574         } else {
 575             return (void*)loadbuffer;
 576         }
 577
 578         printf("Trying /System/OF.bin");
 579         rc=load_raw_firmware(loadbuffer, "/System/OF.bin", MAX_LOADSIZE);
 580         if (rc < EOK) {
 581             printf("Can't load /System/OF.bin");
 582             printf(strerror(rc));
 583         } else {
 584             return (void*)loadbuffer;
 585         }
 586
 587         error(0, 0);
 588
 589     } else {
 590 #if 0 /* e200: enable to be able to dump the hidden partition */
 591         if(btn & BUTTON_UP)
 592         {
 593             int fd;
 594             pinfo = disk_partinfo(1);
 595             fd = open("/part.bin", O_CREAT|O_RDWR);
 596             char sector[512];
 597             for(i=0; i<40960; i++){
 598                 if (!(i%100))
 599                 {
 600                     printf("dumping sector %d", i);
 601                 }
 602                 ata_read_sectors(0, pinfo->start + i, 1, sector);
 603                 write(fd,sector,512);
 604             }
 605             close(fd);
 606         }
 607 #endif
 608         printf("Loading Rockbox...");
 609         rc=load_mi4(loadbuffer, BOOTFILE, MAX_LOADSIZE);
 610         if (rc < EOK) {
 611             printf("Can't load %s:", BOOTFILE);
 612             printf(strerror(rc));
 613
 614 #ifdef OLD_BOOTFILE
 615             /* Try loading rockbox from old rockbox.e200/rockbox.h10 format */
 616             rc=load_firmware(loadbuffer, OLD_BOOTFILE, MAX_LOADSIZE);
 617             if (rc < EOK) {
 618                 printf("Can't load %s:", OLD_BOOTFILE);
 619                 error(EBOOTFILE, rc);
 620             }
 621 #endif
 622         }
 623     }
 624
 625     return (void*)loadbuffer;
 626 }
 627
 628 #if !defined(SANSA_E200) && !defined(SANSA_C200)
 629 /* These functions are present in the firmware library, but we reimplement
 630    them here because the originals do a lot more than we want */
 631 void usb_acknowledge(void)
 632 {
 633 }
 634
 635 void usb_wait_for_disconnect(void)
 636 {
 637 }
 638 #endif
 639