src/jtag/drivers/opendous.c

   1 /***************************************************************************
   2  *                                                                         *
   3  *   Copyright (C) 2009 by Cahya Wirawan <cahya@gmx.at>                    *
   4  *   Based on opendous driver by Vladimir Fonov                            *
   5  *                                                                         *
   6  *   Copyright (C) 2009 by Vladimir Fonov <vladimir.fonov@gmai.com>        *
   7  *   Based on J-link driver by  Juergen Stuber                             *
   8  *                                                                         *
   9  *   Copyright (C) 2007 by Juergen Stuber <juergen@jstuber.net>            *
  10  *   based on Dominic Rath's and Benedikt Sauter's usbprog.c               *
  11  *                                                                         *
  12  *   Copyright (C) 2008 by Spencer Oliver                                  *
  13  *   spen@spen-soft.co.uk                                                  *
  14  *                                                                         *
  15  *   This program is free software; you can redistribute it and/or modify  *
  16  *   it under the terms of the GNU General Public License as published by  *
  17  *   the Free Software Foundation; either version 2 of the License, or     *
  18  *   (at your option) any later version.                                   *
  19  *                                                                         *
  20  *   This program is distributed in the hope that it will be useful,       *
  21  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  22  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  23  *   GNU General Public License for more details.                          *
  24  *                                                                         *
  25  *   You should have received a copy of the GNU General Public License     *
  26  *   along with this program; if not, write to the                         *
  27  *   Free Software Foundation, Inc.,                                       *
  28  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  29  ***************************************************************************/
  30
  31 #ifdef HAVE_CONFIG_H
  32 #include "config.h"
  33 #endif
  34
  35 #include <jtag/interface.h>
  36 #include <jtag/commands.h>
  37 #include "libusb_common.h"
  38 #include <string.h>
  39 #include <sys/timeb.h>
  40 #include <time.h>
  41
  42 #define ESTICK_VID 0x1781
  43 #define ESTICK_PID 0xC0C0
  44
  45 #define OPENDOUS_VID 0x03EB
  46 #define OPENDOUS_PID 0x204F
  47
  48 /* pid could be specified at runtime */
  49 static uint16_t vids[] = { OPENDOUS_VID, ESTICK_VID, 0 };
  50 static uint16_t pids[] = { OPENDOUS_PID, ESTICK_PID, 0 };
  51
  52 #define OPENDOUS_WRITE_ENDPOINT   0x02
  53 #define OPENDOUS_READ_ENDPOINT    0x81
  54
  55 static unsigned int opendous_hw_jtag_version = 1;
  56
  57 #define OPENDOUS_USB_TIMEOUT      1000
  58
  59 #define OPENDOUS_USB_BUFFER_SIZE  360
  60 #define OPENDOUS_IN_BUFFER_SIZE   (OPENDOUS_USB_BUFFER_SIZE)
  61 #define OPENDOUS_OUT_BUFFER_SIZE  (OPENDOUS_USB_BUFFER_SIZE)
  62
  63 /* Global USB buffers */
  64 static uint8_t usb_in_buffer[OPENDOUS_IN_BUFFER_SIZE];
  65 static uint8_t usb_out_buffer[OPENDOUS_OUT_BUFFER_SIZE];
  66
  67 /* Constants for OPENDOUS command */
  68
  69 #define OPENDOUS_MAX_SPEED                      66
  70 #define OPENDOUS_MAX_TAP_TRANSMIT       350     /* even number is easier to handle */
  71 #define OPENDOUS_MAX_INPUT_DATA         (OPENDOUS_MAX_TAP_TRANSMIT*4)
  72
  73 #define OPENDOUS_TAP_BUFFER_SIZE 65536
  74
  75 #define MAX_PENDING_SCAN_RESULTS (OPENDOUS_MAX_INPUT_DATA)
  76
  77 /* JTAG usb commands */
  78 #define JTAG_CMD_TAP_OUTPUT             0x0
  79 #define JTAG_CMD_SET_TRST               0x1
  80 #define JTAG_CMD_SET_SRST               0x2
  81 #define JTAG_CMD_READ_INPUT             0x3
  82 #define JTAG_CMD_TAP_OUTPUT_EMU 0x4
  83 #define JTAG_CMD_SET_DELAY              0x5
  84 #define JTAG_CMD_SET_SRST_TRST  0x6
  85 #define JTAG_CMD_READ_CONFIG    0x7
  86
  87 /* External interface functions */
  88 static int opendous_execute_queue(void);
  89 static int opendous_init(void);
  90 static int opendous_quit(void);
  91
  92 /* Queue command functions */
  93 static void opendous_end_state(tap_state_t state);
  94 static void opendous_state_move(void);
  95 static void opendous_path_move(int num_states, tap_state_t *path);
  96 static void opendous_runtest(int num_cycles);
  97 static void opendous_scan(int ir_scan, enum scan_type type, uint8_t *buffer,
  98                 int scan_size, struct scan_command *command);
  99 static void opendous_reset(int trst, int srst);
 100 static void opendous_simple_command(uint8_t command, uint8_t _data);
 101 static int opendous_get_status(void);
 102
 103 /* opendous tap buffer functions */
 104 static void opendous_tap_init(void);
 105 static int opendous_tap_execute(void);
 106 static void opendous_tap_ensure_space(int scans, int bits);
 107 static void opendous_tap_append_step(int tms, int tdi);
 108 static void opendous_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command);
 109
 110 /* opendous lowlevel functions */
 111 struct opendous_jtag {
 112         struct jtag_libusb_device_handle *usb_handle;
 113 };
 114
 115 static struct opendous_jtag *opendous_usb_open(void);
 116 static void opendous_usb_close(struct opendous_jtag *opendous_jtag);
 117 static int opendous_usb_message(struct opendous_jtag *opendous_jtag, int out_length, int in_length);
 118 static int opendous_usb_write(struct opendous_jtag *opendous_jtag, int out_length);
 119 static int opendous_usb_read(struct opendous_jtag *opendous_jtag);
 120
 121 /* helper functions */
 122 int opendous_get_version_info(void);
 123
 124 #ifdef _DEBUG_USB_COMMS_
 125 char time_str[50];
 126 static void opendous_debug_buffer(uint8_t *buffer, int length);
 127 char *opendous_get_time(char *);
 128 #endif
 129
 130 static struct opendous_jtag *opendous_jtag_handle;
 131
 132 /***************************************************************************/
 133 /* External interface implementation */
 134
 135 COMMAND_HANDLER(opendous_handle_opendous_info_command)
 136 {
 137         if (opendous_get_version_info() == ERROR_OK) {
 138                 /* attempt to get status */
 139                 opendous_get_status();
 140         }
 141
 142         return ERROR_OK;
 143 }
 144
 145 COMMAND_HANDLER(opendous_handle_opendous_hw_jtag_command)
 146 {
 147         switch (CMD_ARGC) {
 148                 case 0:
 149                         command_print(CMD_CTX, "opendous hw jtag  %i", opendous_hw_jtag_version);
 150                         break;
 151
 152                 case 1: {
 153                         int request_version = atoi(CMD_ARGV[0]);
 154                         switch (request_version) {
 155                                 case 2:
 156                                 case 3:
 157                                         opendous_hw_jtag_version = request_version;
 158                                         break;
 159
 160                         default:
 161                                 return ERROR_COMMAND_SYNTAX_ERROR;
 162                         }
 163                         break;
 164                 }
 165
 166                 default:
 167                         return ERROR_COMMAND_SYNTAX_ERROR;
 168         }
 169
 170         return ERROR_OK;
 171 }
 172
 173 static const struct command_registration opendous_command_handlers[] = {
 174         {
 175                 .name = "opendous_info",
 176                 .handler = &opendous_handle_opendous_info_command,
 177                 .mode = COMMAND_EXEC,
 178                 .help = "show opendous info",
 179         },
 180         {
 181                 .name = "opendous_hw_jtag",
 182                 .handler = &opendous_handle_opendous_hw_jtag_command,
 183                 .mode = COMMAND_EXEC,
 184                 .help = "access opendous HW JTAG command version",
 185                 .usage = "[2|3]",
 186         },
 187         COMMAND_REGISTRATION_DONE
 188 };
 189
 190 struct jtag_interface opendous_interface = {
 191         .name = "opendous",
 192         .commands = opendous_command_handlers,
 193         .execute_queue = opendous_execute_queue,
 194         .init = opendous_init,
 195         .quit = opendous_quit,
 196 };
 197
 198 static int opendous_execute_queue(void)
 199 {
 200         struct jtag_command *cmd = jtag_command_queue;
 201         int scan_size;
 202         enum scan_type type;
 203         uint8_t *buffer;
 204
 205         while (cmd != NULL) {
 206                 switch (cmd->type) {
 207                         case JTAG_RUNTEST:
 208                                 DEBUG_JTAG_IO("runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles, \
 209                                         cmd->cmd.runtest->end_state);
 210
 211                                 if (cmd->cmd.runtest->end_state != -1)
 212                                         opendous_end_state(cmd->cmd.runtest->end_state);
 213                                 opendous_runtest(cmd->cmd.runtest->num_cycles);
 214                                 break;
 215
 216                         case JTAG_TLR_RESET:
 217                                 DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
 218
 219                                 if (cmd->cmd.statemove->end_state != -1)
 220                                         opendous_end_state(cmd->cmd.statemove->end_state);
 221                                 opendous_state_move();
 222                                 break;
 223
 224                         case JTAG_PATHMOVE:
 225                                 DEBUG_JTAG_IO("pathmove: %i states, end in %i", \
 226                                         cmd->cmd.pathmove->num_states, \
 227                                         cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
 228
 229                                 opendous_path_move(cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path);
 230                                 break;
 231
 232                         case JTAG_SCAN:
 233                                 DEBUG_JTAG_IO("scan end in %i", cmd->cmd.scan->end_state);
 234
 235                                 if (cmd->cmd.scan->end_state != -1)
 236                                         opendous_end_state(cmd->cmd.scan->end_state);
 237
 238                                 scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
 239                                 DEBUG_JTAG_IO("scan input, length = %d", scan_size);
 240
 241 #ifdef _DEBUG_USB_COMMS_
 242                                 opendous_debug_buffer(buffer, (scan_size + 7) / 8);
 243 #endif
 244                                 type = jtag_scan_type(cmd->cmd.scan);
 245                                 opendous_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size, cmd->cmd.scan);
 246                                 break;
 247
 248                         case JTAG_RESET:
 249                                 DEBUG_JTAG_IO("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 250
 251                                 opendous_tap_execute();
 252
 253                                 if (cmd->cmd.reset->trst == 1)
 254                                         tap_set_state(TAP_RESET);
 255                                 opendous_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 256                                 break;
 257
 258                         case JTAG_SLEEP:
 259                                 DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
 260                                 opendous_tap_execute();
 261                                 jtag_sleep(cmd->cmd.sleep->us);
 262                                 break;
 263
 264                         default:
 265                                 LOG_ERROR("BUG: unknown JTAG command type encountered");
 266                                 exit(-1);
 267                 }
 268                 cmd = cmd->next;
 269         }
 270         return opendous_tap_execute();
 271 }
 272
 273 static int opendous_init(void)
 274 {
 275         int check_cnt;
 276
 277         opendous_jtag_handle = opendous_usb_open();
 278
 279         if (opendous_jtag_handle == 0) {
 280                 LOG_ERROR("Cannot find opendous Interface! Please check connection and permissions.");
 281                 return ERROR_JTAG_INIT_FAILED;
 282         }
 283
 284         check_cnt = 0;
 285         while (check_cnt < 3) {
 286                 if (opendous_get_version_info() == ERROR_OK) {
 287                         /* attempt to get status */
 288                         opendous_get_status();
 289                         break;
 290                 }
 291
 292                 check_cnt++;
 293         }
 294
 295         LOG_INFO("opendous JTAG Interface ready");
 296
 297         opendous_reset(0, 0);
 298         opendous_tap_init();
 299
 300         return ERROR_OK;
 301 }
 302
 303 static int opendous_quit(void)
 304 {
 305         opendous_usb_close(opendous_jtag_handle);
 306         return ERROR_OK;
 307 }
 308
 309 /***************************************************************************/
 310 /* Queue command implementations */
 311
 312 void opendous_end_state(tap_state_t state)
 313 {
 314         if (tap_is_state_stable(state))
 315                 tap_set_end_state(state);
 316         else {
 317                 LOG_ERROR("BUG: %i is not a valid end state", state);
 318                 exit(-1);
 319         }
 320 }
 321
 322 /* Goes to the end state. */
 323 void opendous_state_move(void)
 324 {
 325         int i;
 326         int tms = 0;
 327         uint8_t tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
 328         uint8_t tms_scan_bits = tap_get_tms_path_len(tap_get_state(), tap_get_end_state());
 329
 330         for (i = 0; i < tms_scan_bits; i++) {
 331                 tms = (tms_scan >> i) & 1;
 332                 opendous_tap_append_step(tms, 0);
 333         }
 334
 335         tap_set_state(tap_get_end_state());
 336 }
 337
 338 void opendous_path_move(int num_states, tap_state_t *path)
 339 {
 340         int i;
 341
 342         for (i = 0; i < num_states; i++) {
 343                 if (path[i] == tap_state_transition(tap_get_state(), false))
 344                         opendous_tap_append_step(0, 0);
 345                 else if (path[i] == tap_state_transition(tap_get_state(), true))
 346                         opendous_tap_append_step(1, 0);
 347                 else {
 348                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition",
 349                                         tap_state_name(tap_get_state()), tap_state_name(path[i]));
 350                         exit(-1);
 351                 }
 352
 353                 tap_set_state(path[i]);
 354         }
 355
 356         tap_set_end_state(tap_get_state());
 357 }
 358
 359 void opendous_runtest(int num_cycles)
 360 {
 361         int i;
 362
 363         tap_state_t saved_end_state = tap_get_end_state();
 364
 365         /* only do a state_move when we're not already in IDLE */
 366         if (tap_get_state() != TAP_IDLE) {
 367                 opendous_end_state(TAP_IDLE);
 368                 opendous_state_move();
 369         }
 370
 371         /* execute num_cycles */
 372         for (i = 0; i < num_cycles; i++)
 373                 opendous_tap_append_step(0, 0);
 374
 375         /* finish in end_state */
 376         opendous_end_state(saved_end_state);
 377         if (tap_get_state() != tap_get_end_state())
 378                 opendous_state_move();
 379 }
 380
 381 void opendous_scan(int ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, struct scan_command *command)
 382 {
 383         tap_state_t saved_end_state;
 384
 385         opendous_tap_ensure_space(1, scan_size + 8);
 386
 387         saved_end_state = tap_get_end_state();
 388
 389         /* Move to appropriate scan state */
 390         opendous_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
 391
 392         if (tap_get_state() != tap_get_end_state())
 393                 opendous_state_move();
 394
 395         opendous_end_state(saved_end_state);
 396
 397         /* Scan */
 398         opendous_tap_append_scan(scan_size, buffer, command);
 399
 400         /* We are in Exit1, go to Pause */
 401         opendous_tap_append_step(0, 0);
 402
 403         tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
 404
 405         if (tap_get_state() != tap_get_end_state())
 406                 opendous_state_move();
 407 }
 408
 409 void opendous_reset(int trst, int srst)
 410 {
 411         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 412
 413         /* Signals are active low */
 414 #if 0
 415         if (srst == 0)
 416                 opendous_simple_command(JTAG_CMD_SET_SRST, 1);
 417         else if (srst == 1)
 418                 opendous_simple_command(JTAG_CMD_SET_SRST, 0);
 419
 420         if (trst == 0)
 421                 opendous_simple_command(JTAG_CMD_SET_TRST, 1);
 422         else if (trst == 1)
 423                 opendous_simple_command(JTAG_CMD_SET_TRST, 0);
 424 #endif
 425
 426         srst = srst ? 0 : 1;
 427         trst = trst ? 0 : 2;
 428         opendous_simple_command(JTAG_CMD_SET_SRST_TRST, srst | trst);
 429 }
 430
 431 void opendous_simple_command(uint8_t command, uint8_t _data)
 432 {
 433         int result;
 434
 435         DEBUG_JTAG_IO("0x%02x 0x%02x", command, _data);
 436
 437         usb_out_buffer[0] = 2;
 438         usb_out_buffer[1] = 0;
 439         usb_out_buffer[2] = command;
 440         usb_out_buffer[3] = _data;
 441
 442         result = opendous_usb_message(opendous_jtag_handle, 4, 1);
 443         if (result != 1)
 444                 LOG_ERROR("opendous command 0x%02x failed (%d)", command, result);
 445 }
 446
 447 int opendous_get_status(void)
 448 {
 449         return ERROR_OK;
 450 }
 451
 452 int opendous_get_version_info(void)
 453 {
 454         return ERROR_OK;
 455 }
 456
 457 /***************************************************************************/
 458 /* Estick tap functions */
 459
 460 static int tap_length;
 461 static uint8_t tms_buffer[OPENDOUS_TAP_BUFFER_SIZE];
 462 static uint8_t tdo_buffer[OPENDOUS_TAP_BUFFER_SIZE];
 463
 464 struct pending_scan_result {
 465         int first;      /* First bit position in tdo_buffer to read */
 466         int length; /* Number of bits to read */
 467         struct scan_command *command; /* Corresponding scan command */
 468         uint8_t *buffer;
 469 };
 470
 471 static int pending_scan_results_length;
 472 static struct pending_scan_result pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
 473
 474 static int last_tms;
 475
 476 void opendous_tap_init(void)
 477 {
 478         tap_length = 0;
 479         pending_scan_results_length = 0;
 480 }
 481
 482 void opendous_tap_ensure_space(int scans, int bits)
 483 {
 484         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
 485
 486         if (scans > available_scans)
 487                 opendous_tap_execute();
 488 }
 489
 490 void opendous_tap_append_step(int tms, int tdi)
 491 {
 492         last_tms = tms;
 493         unsigned char _tms = tms ? 1 : 0;
 494         unsigned char _tdi = tdi ? 1 : 0;
 495
 496         int tap_index =  tap_length / 4;
 497         int bits  = (tap_length % 4) * 2;
 498
 499         if (tap_length < OPENDOUS_TAP_BUFFER_SIZE) {
 500                 if (!bits)
 501                         tms_buffer[tap_index] = 0;
 502
 503                 tms_buffer[tap_index] |= (_tdi << bits)|(_tms << (bits + 1)) ;
 504                 tap_length++;
 505         } else
 506                 LOG_ERROR("opendous_tap_append_step, overflow");
 507 }
 508
 509 void opendous_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command)
 510 {
 511         DEBUG_JTAG_IO("append scan, length = %d", length);
 512
 513         struct pending_scan_result *pending_scan_result = &pending_scan_results_buffer[pending_scan_results_length];
 514         int i;
 515
 516         pending_scan_result->first = tap_length;
 517         pending_scan_result->length = length;
 518         pending_scan_result->command = command;
 519         pending_scan_result->buffer = buffer;
 520
 521         for (i = 0; i < length; i++)
 522                 opendous_tap_append_step((i < length-1 ? 0 : 1), (buffer[i / 8] >> (i % 8)) & 1);
 523         pending_scan_results_length++;
 524 }
 525
 526 /* Pad and send a tap sequence to the device, and receive the answer.
 527  * For the purpose of padding we assume that we are in idle or pause state. */
 528 int opendous_tap_execute(void)
 529 {
 530         int byte_length;
 531         int i, j;
 532         int result;
 533
 534 #ifdef _DEBUG_USB_COMMS_
 535         int byte_length_out;
 536 #endif
 537
 538         if (tap_length > 0) {
 539
 540                 /* memset(tdo_buffer,0,OPENDOUS_TAP_BUFFER_SIZE); */
 541                 /* LOG_INFO("OPENDOUS tap execute %d",tap_length); */
 542                 byte_length = (tap_length + 3) / 4;
 543
 544 #ifdef _DEBUG_USB_COMMS_
 545                 byte_length_out = (tap_length + 7) / 8;
 546                 LOG_DEBUG("opendous is sending %d bytes", byte_length);
 547 #endif
 548
 549                 for (j = 0, i = 0; j <  byte_length;) {
 550
 551                         int receive;
 552                         int transmit = byte_length - j;
 553                         if (transmit > OPENDOUS_MAX_TAP_TRANSMIT) {
 554                                 transmit = OPENDOUS_MAX_TAP_TRANSMIT;
 555                                 receive = (OPENDOUS_MAX_TAP_TRANSMIT) / 2;
 556                                 usb_out_buffer[2] = JTAG_CMD_TAP_OUTPUT;
 557                         } else {
 558                                 usb_out_buffer[2] = JTAG_CMD_TAP_OUTPUT | ((tap_length % 4) << 4);
 559                                 receive = (transmit + 1) / 2;
 560                         }
 561                         usb_out_buffer[0] = (transmit + 1) & 0xff;
 562                         usb_out_buffer[1] = ((transmit + 1) >> 8) & 0xff;
 563
 564                         memmove(usb_out_buffer + 3, tms_buffer + j, transmit);
 565                         result = opendous_usb_message(opendous_jtag_handle, 3 + transmit, receive);
 566                         if (result != receive) {
 567                                 LOG_ERROR("opendous_tap_execute, wrong result %d, expected %d", result, receive);
 568                                 return ERROR_JTAG_QUEUE_FAILED;
 569                         }
 570
 571                         memmove(tdo_buffer + i, usb_in_buffer, receive);
 572                         i += receive;
 573                         j += transmit;
 574                 }
 575
 576 #ifdef _DEBUG_USB_COMMS_
 577                 LOG_DEBUG("opendous tap result %d", byte_length_out);
 578                 opendous_debug_buffer(tdo_buffer, byte_length_out);
 579 #endif
 580
 581                 /* LOG_INFO("eStick tap execute %d",tap_length); */
 582                 for (i = 0; i < pending_scan_results_length; i++) {
 583
 584                         struct pending_scan_result *pending_scan_result = &pending_scan_results_buffer[i];
 585                         uint8_t *buffer = pending_scan_result->buffer;
 586                         int length = pending_scan_result->length;
 587                         int first = pending_scan_result->first;
 588                         struct scan_command *command = pending_scan_result->command;
 589
 590                         /* Copy to buffer */
 591                         buf_set_buf(tdo_buffer, first, buffer, 0, length);
 592
 593                         DEBUG_JTAG_IO("pending scan result, length = %d", length);
 594
 595 #ifdef _DEBUG_USB_COMMS_
 596                         opendous_debug_buffer(buffer, byte_length_out);
 597 #endif
 598
 599                         if (jtag_read_buffer(buffer, command) != ERROR_OK) {
 600                                 opendous_tap_init();
 601                                 return ERROR_JTAG_QUEUE_FAILED;
 602                         }
 603
 604                         if (pending_scan_result->buffer != NULL)
 605                                 free(pending_scan_result->buffer);
 606                 }
 607
 608                 opendous_tap_init();
 609         }
 610
 611         return ERROR_OK;
 612 }
 613
 614 /*****************************************************************************/
 615 /* Estick USB low-level functions */
 616
 617 struct opendous_jtag *opendous_usb_open(void)
 618 {
 619         struct opendous_jtag *result;
 620
 621         struct jtag_libusb_device_handle *devh;
 622         if (jtag_libusb_open(vids, pids, &devh) != ERROR_OK)
 623                 return NULL;
 624
 625         jtag_libusb_set_configuration(devh, 0);
 626         jtag_libusb_claim_interface(devh, 0);
 627
 628         result = (struct opendous_jtag *) malloc(sizeof(struct opendous_jtag));
 629         result->usb_handle = devh;
 630         return result;
 631 }
 632
 633 void opendous_usb_close(struct opendous_jtag *opendous_jtag)
 634 {
 635         jtag_libusb_close(opendous_jtag->usb_handle);
 636         free(opendous_jtag);
 637 }
 638
 639 /* Send a message and receive the reply. */
 640 int opendous_usb_message(struct opendous_jtag *opendous_jtag, int out_length, int in_length)
 641 {
 642         int result;
 643
 644         result = opendous_usb_write(opendous_jtag, out_length);
 645         if (result == out_length) {
 646                 result = opendous_usb_read(opendous_jtag);
 647                 if (result == in_length)
 648                         return result;
 649                 else {
 650                         LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)", in_length, result);
 651                         return -1;
 652                 }
 653         } else {
 654                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)", out_length, result);
 655                 return -1;
 656         }
 657 }
 658
 659 /* Write data from out_buffer to USB. */
 660 int opendous_usb_write(struct opendous_jtag *opendous_jtag, int out_length)
 661 {
 662         int result;
 663
 664         if (out_length > OPENDOUS_OUT_BUFFER_SIZE) {
 665                 LOG_ERROR("opendous_jtag_write illegal out_length=%d (max=%d)", out_length, OPENDOUS_OUT_BUFFER_SIZE);
 666                 return -1;
 667         }
 668
 669 #ifdef _DEBUG_USB_COMMS_
 670         LOG_DEBUG("%s: USB write begin", opendous_get_time(time_str));
 671 #endif
 672         result = jtag_libusb_bulk_write(opendous_jtag->usb_handle, OPENDOUS_WRITE_ENDPOINT, \
 673                 (char *)usb_out_buffer, out_length, OPENDOUS_USB_TIMEOUT);
 674 #ifdef _DEBUG_USB_COMMS_
 675         LOG_DEBUG("%s: USB write end: %d bytes", opendous_get_time(time_str), result);
 676 #endif
 677
 678         DEBUG_JTAG_IO("opendous_usb_write, out_length = %d, result = %d", out_length, result);
 679
 680 #ifdef _DEBUG_USB_COMMS_
 681         opendous_debug_buffer(usb_out_buffer, out_length);
 682 #endif
 683         return result;
 684 }
 685
 686 /* Read data from USB into in_buffer. */
 687 int opendous_usb_read(struct opendous_jtag *opendous_jtag)
 688 {
 689 #ifdef _DEBUG_USB_COMMS_
 690         LOG_DEBUG("%s: USB read begin", opendous_get_time(time_str));
 691 #endif
 692         int result = jtag_libusb_bulk_read(opendous_jtag->usb_handle, OPENDOUS_READ_ENDPOINT,
 693                 (char *)usb_in_buffer, OPENDOUS_IN_BUFFER_SIZE, OPENDOUS_USB_TIMEOUT);
 694 #ifdef _DEBUG_USB_COMMS_
 695         LOG_DEBUG("%s: USB read end: %d bytes", opendous_get_time(time_str), result);
 696 #endif
 697         DEBUG_JTAG_IO("opendous_usb_read, result = %d", result);
 698
 699 #ifdef _DEBUG_USB_COMMS_
 700         opendous_debug_buffer(usb_in_buffer, result);
 701 #endif
 702         return result;
 703 }
 704
 705 #ifdef _DEBUG_USB_COMMS_
 706 #define BYTES_PER_LINE  16
 707
 708 void opendous_debug_buffer(uint8_t *buffer, int length)
 709 {
 710         char line[81];
 711         char s[4];
 712         int i;
 713         int j;
 714
 715         for (i = 0; i < length; i += BYTES_PER_LINE) {
 716                 snprintf(line, 5, "%04x", i);
 717                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++) {
 718                         snprintf(s, 4, " %02x", buffer[j]);
 719                         strcat(line, s);
 720                 }
 721                 LOG_DEBUG("%s", line);
 722         }
 723 }
 724
 725 char *opendous_get_time(char *str)
 726 {
 727         struct timeb timebuffer;
 728         char *timeline;
 729
 730         ftime(&timebuffer);
 731         timeline = ctime(&(timebuffer.time));
 732         snprintf(str, 49, "%.8s.%hu", &timeline[11], timebuffer.millitm);
 733         return str;
 734 }
 735 #endif