src/jtag/drivers/ti_icdi_usb.c

   1 /***************************************************************************
   2  *                                                                         *
   3  *   Copyright (C) 2012 by Spencer Oliver                                  *
   4  *   spen@spen-soft.co.uk                                                  *
   5  *                                                                         *
   6  *   This program is free software; you can redistribute it and/or modify  *
   7  *   it under the terms of the GNU General Public License as published by  *
   8  *   the Free Software Foundation; either version 2 of the License, or     *
   9  *   (at your option) any later version.                                   *
  10  *                                                                         *
  11  *   This program is distributed in the hope that it will be useful,       *
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  14  *   GNU General Public License for more details.                          *
  15  *                                                                         *
  16  *   You should have received a copy of the GNU General Public License     *
  17  *   along with this program; if not, write to the                         *
  18  *   Free Software Foundation, Inc.,                                       *
  19  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
  20  ***************************************************************************/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25
  26 /* project specific includes */
  27 #include <helper/binarybuffer.h>
  28 #include <jtag/interface.h>
  29 #include <jtag/hla/hla_layout.h>
  30 #include <jtag/hla/hla_transport.h>
  31 #include <jtag/hla/hla_interface.h>
  32 #include <target/target.h>
  33
  34 #include <target/cortex_m.h>
  35
  36 #include <libusb.h>
  37
  38 #define ICDI_WRITE_ENDPOINT 0x02
  39 #define ICDI_READ_ENDPOINT 0x83
  40
  41 #define ICDI_WRITE_TIMEOUT 1000
  42 #define ICDI_READ_TIMEOUT 1000
  43 #define ICDI_PACKET_SIZE 2048
  44
  45 #define PACKET_START "$"
  46 #define PACKET_END "#"
  47
  48 struct icdi_usb_handle_s {
  49         libusb_context *usb_ctx;
  50         libusb_device_handle *usb_dev;
  51
  52         char *read_buffer;
  53         char *write_buffer;
  54         int max_packet;
  55         int read_count;
  56         uint32_t max_rw_packet; /* max X packet (read/write memory) transfers */
  57 };
  58
  59 static int icdi_usb_read_mem(void *handle, uint32_t addr, uint32_t size,
  60                 uint32_t count, uint8_t *buffer);
  61 static int icdi_usb_write_mem(void *handle, uint32_t addr, uint32_t size,
  62                 uint32_t count, const uint8_t *buffer);
  63
  64 static int remote_escape_output(const char *buffer, int len, char *out_buf, int *out_len, int out_maxlen)
  65 {
  66         int input_index, output_index;
  67
  68         output_index = 0;
  69
  70         for (input_index = 0; input_index < len; input_index++) {
  71
  72                 char b = buffer[input_index];
  73
  74                 if (b == '$' || b == '#' || b == '}' || b == '*') {
  75                         /* These must be escaped.  */
  76                         if (output_index + 2 > out_maxlen)
  77                                 break;
  78                         out_buf[output_index++] = '}';
  79                         out_buf[output_index++] = b ^ 0x20;
  80                 } else {
  81                         if (output_index + 1 > out_maxlen)
  82                                 break;
  83                         out_buf[output_index++] = b;
  84                 }
  85         }
  86
  87         *out_len = input_index;
  88         return output_index;
  89 }
  90
  91 static int remote_unescape_input(const char *buffer, int len, char *out_buf, int out_maxlen)
  92 {
  93         int input_index, output_index;
  94         int escaped;
  95
  96         output_index = 0;
  97         escaped = 0;
  98
  99         for (input_index = 0; input_index < len; input_index++) {
 100
 101                 char b = buffer[input_index];
 102
 103                 if (output_index + 1 > out_maxlen)
 104                         LOG_ERROR("Received too much data from the target.");
 105
 106                 if (escaped) {
 107                         out_buf[output_index++] = b ^ 0x20;
 108                         escaped = 0;
 109                 } else if (b == '}')
 110                         escaped = 1;
 111                 else
 112                         out_buf[output_index++] = b;
 113         }
 114
 115         if (escaped)
 116                 LOG_ERROR("Unmatched escape character in target response.");
 117
 118         return output_index;
 119 }
 120
 121 static int icdi_send_packet(void *handle, int len)
 122 {
 123         unsigned char cksum = 0;
 124         struct icdi_usb_handle_s *h = handle;
 125         int result, retry = 0;
 126         int transferred = 0;
 127
 128         assert(handle != NULL);
 129
 130         /* check we have a large enough buffer for checksum "#00" */
 131         if (len + 3 > h->max_packet) {
 132                 LOG_ERROR("packet buffer too small");
 133                 return ERROR_FAIL;
 134         }
 135
 136         /* calculate checksum - offset start of packet */
 137         for (int i = 1; i < len; i++)
 138                 cksum += h->write_buffer[i];
 139
 140         len += sprintf(&h->write_buffer[len], PACKET_END "%02x", cksum);
 141
 142 #ifdef _DEBUG_USB_COMMS_
 143         char buffer[50];
 144         char ch = h->write_buffer[1];
 145         if (ch == 'x' || ch == 'X')
 146                 LOG_DEBUG("writing packet: <binary>");
 147         else {
 148                 memcpy(buffer, h->write_buffer, len >= 50 ? 50-1 : len);
 149                 buffer[len] = 0;
 150                 LOG_DEBUG("writing packet: %s", buffer);
 151         }
 152 #endif
 153
 154         while (1) {
 155
 156                 result = libusb_bulk_transfer(h->usb_dev, ICDI_WRITE_ENDPOINT, (unsigned char *)h->write_buffer, len,
 157                                 &transferred, ICDI_WRITE_TIMEOUT);
 158                 if (result != 0 || transferred != len) {
 159                         LOG_DEBUG("Error TX Data %d", result);
 160                         return ERROR_FAIL;
 161                 }
 162
 163                 /* check that the client got the message ok, or shall we resend */
 164                 result = libusb_bulk_transfer(h->usb_dev, ICDI_READ_ENDPOINT, (unsigned char *)h->read_buffer, h->max_packet,
 165                                         &transferred, ICDI_READ_TIMEOUT);
 166                 if (result != 0 || transferred < 1) {
 167                         LOG_DEBUG("Error RX Data %d", result);
 168                         return ERROR_FAIL;
 169                 }
 170
 171 #ifdef _DEBUG_USB_COMMS_
 172                 LOG_DEBUG("received reply: '%c' : count %d", h->read_buffer[0], transferred);
 173 #endif
 174
 175                 if (h->read_buffer[0] == '-') {
 176                         LOG_DEBUG("Resending packet %d", ++retry);
 177                 } else {
 178                         if (h->read_buffer[0] != '+')
 179                                 LOG_DEBUG("Unexpected Reply from ICDI: %c", h->read_buffer[0]);
 180                         break;
 181                 }
 182
 183                 if (retry == 3) {
 184                         LOG_DEBUG("maximum nack retries attempted");
 185                         return ERROR_FAIL;
 186                 }
 187         }
 188
 189         retry = 0;
 190         h->read_count = transferred;
 191
 192         while (1) {
 193
 194                 /* read reply from icdi */
 195                 result = libusb_bulk_transfer(h->usb_dev, ICDI_READ_ENDPOINT, (unsigned char *)h->read_buffer + h->read_count,
 196                                 h->max_packet - h->read_count, &transferred, ICDI_READ_TIMEOUT);
 197
 198 #ifdef _DEBUG_USB_COMMS_
 199                 LOG_DEBUG("received data: count %d", transferred);
 200 #endif
 201
 202                 /* check for errors but retry for timeout */
 203                 if (result != 0) {
 204
 205                         if (result == LIBUSB_ERROR_TIMEOUT) {
 206                                 LOG_DEBUG("Error RX timeout %d", result);
 207                         } else {
 208                                 LOG_DEBUG("Error RX Data %d", result);
 209                                 return ERROR_FAIL;
 210                         }
 211                 }
 212
 213                 h->read_count += transferred;
 214
 215                 /* we need to make sure we have a full packet, including checksum */
 216                 if (h->read_count > 5) {
 217
 218                         /* check that we have received an packet delimiter
 219                          * we do not validate the checksum
 220                          * reply should contain $...#AA - so we check for # */
 221                         if (h->read_buffer[h->read_count - 3] == '#')
 222                                 return ERROR_OK;
 223                 }
 224
 225                 if (retry++ == 3) {
 226                         LOG_DEBUG("maximum data retries attempted");
 227                         break;
 228                 }
 229         }
 230
 231         return ERROR_FAIL;
 232 }
 233
 234 static int icdi_send_cmd(void *handle, const char *cmd)
 235 {
 236         struct icdi_usb_handle_s *h = handle;
 237
 238         int cmd_len = snprintf(h->write_buffer, h->max_packet, PACKET_START "%s", cmd);
 239         return icdi_send_packet(handle, cmd_len);
 240 }
 241
 242 static int icdi_send_remote_cmd(void *handle, const char *data)
 243 {
 244         struct icdi_usb_handle_s *h = handle;
 245
 246         size_t cmd_len = sprintf(h->write_buffer, PACKET_START "qRcmd,");
 247         cmd_len += hexify(h->write_buffer + cmd_len, data, 0, h->max_packet - cmd_len);
 248
 249         return icdi_send_packet(handle, cmd_len);
 250 }
 251
 252 static int icdi_get_cmd_result(void *handle)
 253 {
 254         struct icdi_usb_handle_s *h = handle;
 255         int offset = 0;
 256         char ch;
 257
 258         assert(handle != NULL);
 259
 260         do {
 261                 ch = h->read_buffer[offset++];
 262                 if (offset > h->read_count)
 263                         return ERROR_FAIL;
 264         } while (ch != '$');
 265
 266         if (memcmp("OK", h->read_buffer + offset, 2) == 0)
 267                 return ERROR_OK;
 268
 269         if (h->read_buffer[offset] == 'E') {
 270                 /* get error code */
 271                 char result;
 272                 if (unhexify(&result, h->read_buffer + offset + 1, 1) != 1)
 273                         return ERROR_FAIL;
 274                 return result;
 275         }
 276
 277         /* for now we assume everything else is ok */
 278         return ERROR_OK;
 279 }
 280
 281 static int icdi_usb_idcode(void *handle, uint32_t *idcode)
 282 {
 283         *idcode = 0;
 284         return ERROR_OK;
 285 }
 286
 287 static int icdi_usb_write_debug_reg(void *handle, uint32_t addr, uint32_t val)
 288 {
 289         uint8_t buf[4];
 290         /* REVISIT: There's no target pointer here so there's no way to use target_buffer_set_u32().
 291          * I guess all supported chips are little-endian anyway. */
 292         h_u32_to_le(buf, val);
 293         return icdi_usb_write_mem(handle, addr, 4, 1, buf);
 294 }
 295
 296 static enum target_state icdi_usb_state(void *handle)
 297 {
 298         int result;
 299         struct icdi_usb_handle_s *h = handle;
 300         uint32_t dhcsr;
 301         uint8_t buf[4];
 302
 303         result = icdi_usb_read_mem(h, DCB_DHCSR, 4, 1, buf);
 304         if (result != ERROR_OK)
 305                 return TARGET_UNKNOWN;
 306
 307         /* REVISIT: There's no target pointer here so there's no way to use target_buffer_get_u32().
 308          * I guess all supported chips are little-endian anyway. */
 309         dhcsr = le_to_h_u32(buf);
 310         if (dhcsr & S_HALT)
 311                 return TARGET_HALTED;
 312
 313         return TARGET_RUNNING;
 314 }
 315
 316 static int icdi_usb_version(void *handle)
 317 {
 318         struct icdi_usb_handle_s *h = handle;
 319
 320         char version[20];
 321
 322         /* get info about icdi */
 323         int result = icdi_send_remote_cmd(handle, "version");
 324         if (result != ERROR_OK)
 325                 return result;
 326
 327         if (h->read_count < 8) {
 328                 LOG_ERROR("Invalid Reply Received");
 329                 return ERROR_FAIL;
 330         }
 331
 332         /* convert reply */
 333         if (unhexify(version, h->read_buffer + 2, 4) != 4) {
 334                 LOG_WARNING("unable to get ICDI version");
 335                 return ERROR_OK;
 336         }
 337
 338         /* null terminate and print info */
 339         version[4] = 0;
 340
 341         LOG_INFO("ICDI Firmware version: %s", version);
 342
 343         return ERROR_OK;
 344 }
 345
 346 static int icdi_usb_query(void *handle)
 347 {
 348         int result;
 349
 350         struct icdi_usb_handle_s *h = handle;
 351
 352         result = icdi_send_cmd(handle, "qSupported");
 353         if (result != ERROR_OK)
 354                 return result;
 355
 356         /* check result */
 357         result = icdi_get_cmd_result(handle);
 358         if (result != ERROR_OK) {
 359                 LOG_ERROR("query supported failed: 0x%x", result);
 360                 return ERROR_FAIL;
 361         }
 362
 363         /* from this we can get the max packet supported */
 364
 365         /* query packet buffer size */
 366         char *offset = strstr(h->read_buffer, "PacketSize");
 367         if (offset) {
 368                 char *separator;
 369                 int max_packet;
 370
 371                 max_packet = strtoul(offset + 11, &separator, 16);
 372                 if (!max_packet)
 373                         LOG_ERROR("invalid max packet, using defaults");
 374                 else
 375                         h->max_packet = max_packet;
 376                 LOG_DEBUG("max packet supported : %" PRIu32 " bytes", h->max_packet);
 377         }
 378
 379
 380         /* if required re allocate packet buffer */
 381         if (h->max_packet != ICDI_PACKET_SIZE) {
 382                 h->read_buffer = realloc(h->read_buffer, h->max_packet);
 383                 h->write_buffer = realloc(h->write_buffer, h->max_packet);
 384                 if (h->read_buffer == 0 || h->write_buffer == 0) {
 385                         LOG_ERROR("unable to reallocate memory");
 386                         return ERROR_FAIL;
 387                 }
 388         }
 389
 390         /* set extended mode */
 391         result = icdi_send_cmd(handle, "!");
 392         if (result != ERROR_OK)
 393                 return result;
 394
 395         /* check result */
 396         result = icdi_get_cmd_result(handle);
 397         if (result != ERROR_OK) {
 398                 LOG_ERROR("unable to enable extended mode: 0x%x", result);
 399                 return ERROR_FAIL;
 400         }
 401
 402         return ERROR_OK;
 403 }
 404
 405 static int icdi_usb_reset(void *handle)
 406 {
 407         /* we do this in hla_target.c */
 408         return ERROR_OK;
 409 }
 410
 411 static int icdi_usb_assert_srst(void *handle, int srst)
 412 {
 413         /* TODO not supported yet */
 414         return ERROR_COMMAND_NOTFOUND;
 415 }
 416
 417 static int icdi_usb_run(void *handle)
 418 {
 419         int result;
 420
 421         /* resume target at current address */
 422         result = icdi_send_cmd(handle, "c");
 423         if (result != ERROR_OK)
 424                 return result;
 425
 426         /* check result */
 427         result = icdi_get_cmd_result(handle);
 428         if (result != ERROR_OK) {
 429                 LOG_ERROR("continue failed: 0x%x", result);
 430                 return ERROR_FAIL;
 431         }
 432
 433         return result;
 434 }
 435
 436 static int icdi_usb_halt(void *handle)
 437 {
 438         int result;
 439
 440         /* this query halts the target ?? */
 441         result = icdi_send_cmd(handle, "?");
 442         if (result != ERROR_OK)
 443                 return result;
 444
 445         /* check result */
 446         result = icdi_get_cmd_result(handle);
 447         if (result != ERROR_OK) {
 448                 LOG_ERROR("halt failed: 0x%x", result);
 449                 return ERROR_FAIL;
 450         }
 451
 452         return result;
 453 }
 454
 455 static int icdi_usb_step(void *handle)
 456 {
 457         int result;
 458
 459         /* step target at current address */
 460         result = icdi_send_cmd(handle, "s");
 461         if (result != ERROR_OK)
 462                 return result;
 463
 464         /* check result */
 465         result = icdi_get_cmd_result(handle);
 466         if (result != ERROR_OK) {
 467                 LOG_ERROR("step failed: 0x%x", result);
 468                 return ERROR_FAIL;
 469         }
 470
 471         return result;
 472 }
 473
 474 static int icdi_usb_read_regs(void *handle)
 475 {
 476         /* currently unsupported */
 477         return ERROR_OK;
 478 }
 479
 480 static int icdi_usb_read_reg(void *handle, int num, uint32_t *val)
 481 {
 482         int result;
 483         struct icdi_usb_handle_s *h = handle;
 484         char cmd[10];
 485
 486         snprintf(cmd, sizeof(cmd), "p%x", num);
 487         result = icdi_send_cmd(handle, cmd);
 488         if (result != ERROR_OK)
 489                 return result;
 490
 491         /* check result */
 492         result = icdi_get_cmd_result(handle);
 493         if (result != ERROR_OK) {
 494                 LOG_ERROR("register read failed: 0x%x", result);
 495                 return ERROR_FAIL;
 496         }
 497
 498         /* convert result */
 499         uint8_t buf[4];
 500         if (unhexify((char *)buf, h->read_buffer + 2, 4) != 4) {
 501                 LOG_ERROR("failed to convert result");
 502                 return ERROR_FAIL;
 503         }
 504         *val = le_to_h_u32(buf);
 505
 506         return result;
 507 }
 508
 509 static int icdi_usb_write_reg(void *handle, int num, uint32_t val)
 510 {
 511         int result;
 512         char cmd[20];
 513         uint8_t buf[4];
 514         h_u32_to_le(buf, val);
 515
 516         int cmd_len = snprintf(cmd, sizeof(cmd), "P%x=", num);
 517         hexify(cmd + cmd_len, (const char *)buf, 4, sizeof(cmd));
 518
 519         result = icdi_send_cmd(handle, cmd);
 520         if (result != ERROR_OK)
 521                 return result;
 522
 523         /* check result */
 524         result = icdi_get_cmd_result(handle);
 525         if (result != ERROR_OK) {
 526                 LOG_ERROR("register write failed: 0x%x", result);
 527                 return ERROR_FAIL;
 528         }
 529
 530         return result;
 531 }
 532
 533 static int icdi_usb_read_mem_int(void *handle, uint32_t addr, uint32_t len, uint8_t *buffer)
 534 {
 535         int result;
 536         struct icdi_usb_handle_s *h = handle;
 537         char cmd[20];
 538
 539         snprintf(cmd, sizeof(cmd), "x%x,%x", addr, len);
 540         result = icdi_send_cmd(handle, cmd);
 541         if (result != ERROR_OK)
 542                 return result;
 543
 544         /* check result */
 545         result = icdi_get_cmd_result(handle);
 546         if (result != ERROR_OK) {
 547                 LOG_ERROR("memory read failed: 0x%x", result);
 548                 return ERROR_FAIL;
 549         }
 550
 551         /* unescape input */
 552         int read_len = remote_unescape_input(h->read_buffer + 5, h->read_count - 8, (char *)buffer, len);
 553         if (read_len != (int)len) {
 554                 LOG_ERROR("read more bytes than expected: actual 0x%" PRIx32 " expected 0x%" PRIx32, read_len, len);
 555                 return ERROR_FAIL;
 556         }
 557
 558         return ERROR_OK;
 559 }
 560
 561 static int icdi_usb_write_mem_int(void *handle, uint32_t addr, uint32_t len, const uint8_t *buffer)
 562 {
 563         int result;
 564         struct icdi_usb_handle_s *h = handle;
 565
 566         size_t cmd_len = snprintf(h->write_buffer, h->max_packet, PACKET_START "X%x,%x:", addr, len);
 567
 568         int out_len;
 569         cmd_len += remote_escape_output((const char *)buffer, len, h->write_buffer + cmd_len,
 570                         &out_len, h->max_packet - cmd_len);
 571
 572         if (out_len < (int)len) {
 573                 /* for now issue a error as we have no way of allocating a larger buffer */
 574                 LOG_ERROR("memory buffer too small: requires 0x%" PRIx32 " actual 0x%" PRIx32, out_len, len);
 575                 return ERROR_FAIL;
 576         }
 577
 578         result = icdi_send_packet(handle, cmd_len);
 579         if (result != ERROR_OK)
 580                 return result;
 581
 582         /* check result */
 583         result = icdi_get_cmd_result(handle);
 584         if (result != ERROR_OK) {
 585                 LOG_ERROR("memory write failed: 0x%x", result);
 586                 return ERROR_FAIL;
 587         }
 588
 589         return ERROR_OK;
 590 }
 591
 592 static int icdi_usb_read_mem(void *handle, uint32_t addr, uint32_t size,
 593                 uint32_t count, uint8_t *buffer)
 594 {
 595         int retval = ERROR_OK;
 596         struct icdi_usb_handle_s *h = handle;
 597         uint32_t bytes_remaining;
 598
 599         /* calculate byte count */
 600         count *= size;
 601
 602         while (count) {
 603
 604                 bytes_remaining = h->max_rw_packet;
 605                 if (count < bytes_remaining)
 606                         bytes_remaining = count;
 607
 608                 retval = icdi_usb_read_mem_int(handle, addr, bytes_remaining, buffer);
 609                 if (retval != ERROR_OK)
 610                         return retval;
 611
 612                 buffer += bytes_remaining;
 613                 addr += bytes_remaining;
 614                 count -= bytes_remaining;
 615         }
 616
 617         return retval;
 618 }
 619
 620 static int icdi_usb_write_mem(void *handle, uint32_t addr, uint32_t size,
 621                 uint32_t count, const uint8_t *buffer)
 622 {
 623         int retval = ERROR_OK;
 624         struct icdi_usb_handle_s *h = handle;
 625         uint32_t bytes_remaining;
 626
 627         /* calculate byte count */
 628         count *= size;
 629
 630         while (count) {
 631
 632                 bytes_remaining = h->max_rw_packet;
 633                 if (count < bytes_remaining)
 634                         bytes_remaining = count;
 635
 636                 retval = icdi_usb_write_mem_int(handle, addr, bytes_remaining, buffer);
 637                 if (retval != ERROR_OK)
 638                         return retval;
 639
 640                 buffer += bytes_remaining;
 641                 addr += bytes_remaining;
 642                 count -= bytes_remaining;
 643         }
 644
 645         return retval;
 646 }
 647
 648 static int icdi_usb_close(void *handle)
 649 {
 650         struct icdi_usb_handle_s *h = handle;
 651
 652         if (h->usb_dev)
 653                 libusb_close(h->usb_dev);
 654
 655         if (h->usb_ctx)
 656                 libusb_exit(h->usb_ctx);
 657
 658         if (h->read_buffer)
 659                 free(h->read_buffer);
 660
 661         if (h->write_buffer)
 662                 free(h->write_buffer);
 663
 664         free(handle);
 665
 666         return ERROR_OK;
 667 }
 668
 669 static int icdi_usb_open(struct hl_interface_param_s *param, void **fd)
 670 {
 671         int retval;
 672         struct icdi_usb_handle_s *h;
 673
 674         LOG_DEBUG("icdi_usb_open");
 675
 676         h = calloc(1, sizeof(struct icdi_usb_handle_s));
 677
 678         if (h == 0) {
 679                 LOG_ERROR("unable to allocate memory");
 680                 return ERROR_FAIL;
 681         }
 682
 683         LOG_DEBUG("transport: %d vid: 0x%04x pid: 0x%04x", param->transport,
 684                 param->vid, param->pid);
 685
 686         if (libusb_init(&h->usb_ctx) != 0) {
 687                 LOG_ERROR("libusb init failed");
 688                 goto error_open;
 689         }
 690
 691         h->usb_dev = libusb_open_device_with_vid_pid(h->usb_ctx, param->vid, param->pid);
 692         if (!h->usb_dev) {
 693                 LOG_ERROR("open failed");
 694                 goto error_open;
 695         }
 696
 697         if (libusb_claim_interface(h->usb_dev, 2)) {
 698                 LOG_DEBUG("claim interface failed");
 699                 goto error_open;
 700         }
 701
 702         /* check if mode is supported */
 703         retval = ERROR_OK;
 704
 705         switch (param->transport) {
 706 #if 0
 707                 /* TODO place holder as swd is not currently supported */
 708                 case HL_TRANSPORT_SWD:
 709 #endif
 710                 case HL_TRANSPORT_JTAG:
 711                         break;
 712                 default:
 713                         retval = ERROR_FAIL;
 714                         break;
 715         }
 716
 717         if (retval != ERROR_OK) {
 718                 LOG_ERROR("mode (transport) not supported by device");
 719                 goto error_open;
 720         }
 721
 722         /* allocate buffer */
 723         h->read_buffer = malloc(ICDI_PACKET_SIZE);
 724         h->write_buffer = malloc(ICDI_PACKET_SIZE);
 725         h->max_packet = ICDI_PACKET_SIZE;
 726
 727         if (h->read_buffer == 0 || h->write_buffer == 0) {
 728                 LOG_DEBUG("malloc failed");
 729                 goto error_open;
 730         }
 731
 732         /* query icdi version etc */
 733         retval = icdi_usb_version(h);
 734         if (retval != ERROR_OK)
 735                 goto error_open;
 736
 737         /* query icdi support */
 738         retval = icdi_usb_query(h);
 739         if (retval != ERROR_OK)
 740                 goto error_open;
 741
 742         *fd = h;
 743
 744         /* set the max target read/write buffer in bytes
 745          * as we are using gdb binary packets to transfer memory we have to
 746          * reserve half the buffer for any possible escape chars plus
 747          * at least 64 bytes for the gdb packet header */
 748         h->max_rw_packet = (((h->max_packet - 64) / 4) * 4) / 2;
 749
 750         return ERROR_OK;
 751
 752 error_open:
 753         icdi_usb_close(h);
 754
 755         return ERROR_FAIL;
 756 }
 757
 758 struct hl_layout_api_s icdi_usb_layout_api = {
 759         .open = icdi_usb_open,
 760         .close = icdi_usb_close,
 761         .idcode = icdi_usb_idcode,
 762         .state = icdi_usb_state,
 763         .reset = icdi_usb_reset,
 764         .assert_srst = icdi_usb_assert_srst,
 765         .run = icdi_usb_run,
 766         .halt = icdi_usb_halt,
 767         .step = icdi_usb_step,
 768         .read_regs = icdi_usb_read_regs,
 769         .read_reg = icdi_usb_read_reg,
 770         .write_reg = icdi_usb_write_reg,
 771         .read_mem = icdi_usb_read_mem,
 772         .write_mem = icdi_usb_write_mem,
 773         .write_debug_reg = icdi_usb_write_debug_reg
 774 };