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   1 /***************************************************************************
   2  *   Driver for USB-JTAG, Altera USB-Blaster and compatibles               *
   3  *   Original code from Kolja Waschk's USB-JTAG project                    *
   4  *     (http://www.ixo.de/info/usb_jtag/).                                 *
   5  *   Some updates by Anthony Liu (2006).                                   *
   6  *   Minor updates and cleanup by Catalin Patulea (2009).                  *
   7  *   Speed updates by Ali Lown (2011).                                     *
   8  *                                                                         *
   9  *   Copyright (C) 2011 Ali Lown                                           *
  10  *   ali@lown.me.uk                                                        *
  11  *                                                                         *
  12  *   Copyright (C) 2009 Catalin Patulea                                    *
  13  *   cat@vv.carleton.ca                                                    *
  14  *                                                                         *
  15  *   Copyright (C) 2006 Kolja Waschk                                       *
  16  *   usbjtag@ixo.de                                                        *
  17  *                                                                         *
  18  *   Based on ft2232.c and bitbang.c,                                      *
  19  *   Copyright (C) 2004,2006 by Dominic Rath                               *
  20  *                                                                         *
  21  *   This program is free software; you can redistribute it and/or modify  *
  22  *   it under the terms of the GNU General Public License as published by  *
  23  *   the Free Software Foundation; either version 2 of the License, or     *
  24  *   (at your option) any later version.                                   *
  25  *                                                                         *
  26  *   This program is distributed in the hope that it will be useful,       *
  27  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  28  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  29  *   GNU General Public License for more details.                          *
  30  *                                                                         *
  31  *   You should have received a copy of the GNU General Public License     *
  32  *   along with this program; if not, write to the                         *
  33  *   Free Software Foundation, Inc.,                                       *
  34  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  35  ***************************************************************************/
  36
  37 /*
  38  * The following information is originally from Kolja Waschk's USB-JTAG,
  39  * where it was obtained by reverse engineering an Altera USB-Blaster.
  40  * See http://www.ixo.de/info/usb_jtag/ for USB-Blaster block diagram and
  41  * usb_jtag-20080705-1200.zip#usb_jtag/host/openocd for protocol.
  42  *
  43  * The same information is also on the UrJTAG mediawiki, with some additional
  44  * notes on bits marked as "unknown" by usb_jtag.
  45  * (http://sourceforge.net/apps/mediawiki/urjtag/index.php?
  46  *    title=Cable_Altera_USB-Blaster)
  47  *
  48  * USB-JTAG, Altera USB-Blaster and compatibles are typically implemented as
  49  * an FTDIChip FT245 followed by a CPLD which handles a two-mode protocol:
  50  *
  51  *            _________
  52  *           |         |
  53  *           | AT93C46 |
  54  *           |_________|
  55  *            __|__________    _________
  56  *           |             |  |         |
  57  *      USB__| FTDI 245BM  |__| EPM7064 |__JTAG (B_TDO,B_TDI,B_TMS,B_TCK)
  58  *           |_____________|  |_________|
  59  *            __|__________    _|___________
  60  *           |             |  |             |
  61  *           | 6 MHz XTAL  |  | 24 MHz Osc. |
  62  *           |_____________|  |_____________|
  63  *
  64  * Protocol details are given in the code below.
  65  *
  66  * It is also possible to emulate this configuration using a single-chip USB
  67  * controller like the Cypress FX2 (again, see usb_jtag for details).
  68  */
  69 #ifdef HAVE_CONFIG_H
  70 #include "config.h"
  71 #endif
  72
  73 #if IS_CYGWIN == 1
  74 #include "windows.h"
  75 #undef LOG_ERROR
  76 #endif
  77
  78 /* project specific includes */
  79 #include <jtag/interface.h>
  80 #include <jtag/commands.h>
  81 #include <helper/time_support.h>
  82
  83 /* system includes */
  84 #include <string.h>
  85 #include <stdlib.h>
  86 #include <unistd.h>
  87
  88 #include "bitbang.h"
  89
  90 #if (BUILD_USB_BLASTER_FTD2XX == 1 && BUILD_USB_BLASTER_LIBFTDI == 1)
  91 #error "BUILD_USB_BLASTER_FTD2XX && BUILD_USB_BLASTER_LIBFTDI "
  92            "are mutually exclusive"
  93 #elif (BUILD_USB_BLASTER_FTD2XX != 1 && BUILD_USB_BLASTER_LIBFTDI != 1)
  94 #error "BUILD_USB_BLASTER_FTD2XX || BUILD_USB_BLASTER_LIBFTDI must be chosen"
  95 #endif
  96
  97 /* USB_BLASTER access library includes */
  98 #if BUILD_USB_BLASTER_FTD2XX == 1
  99 #include <ftd2xx.h>
 100 #include "ftd2xx_common.h"
 101 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 102 #include <ftdi.h>
 103 #endif
 104
 105 #include <sys/time.h>
 106 #include <time.h>
 107
 108 static char *usb_blaster_device_desc;
 109 static uint16_t usb_blaster_vid = 0x09fb; /* Altera */
 110 static uint16_t usb_blaster_pid = 0x6001; /* USB-Blaster */
 111
 112 /* last output byte in simple bit banging (legacy) mode */
 113 static uint8_t out_value;
 114 /* global output buffer for bit banging */
 115 #define BUF_LEN 64 //Size of EP1
 116 static uint8_t out_buffer[BUF_LEN];
 117 static uint16_t out_count = 0;
 118
 119 #if BUILD_USB_BLASTER_FTD2XX == 1
 120 static FT_HANDLE ftdih;
 121 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 122 static struct ftdi_context ftdic;
 123 #endif
 124
 125 static int usb_blaster_buf_write(
 126         uint8_t *buf, int size, uint32_t *bytes_written)
 127 {
 128 #if BUILD_USB_BLASTER_FTD2XX == 1
 129         FT_STATUS status;
 130         DWORD dw_bytes_written;
 131
 132 #ifdef _DEBUG_JTAG_IO_
 133         LOG_DEBUG("usb_blaster_buf_write %02X (%d)", buf[0], size);
 134 #endif
 135         status = FT_Write(ftdih, buf, size, &dw_bytes_written);
 136         if (status != FT_OK)
 137         {
 138                 *bytes_written = dw_bytes_written;
 139                 LOG_ERROR("FT_Write returned: %s", ftd2xx_status_string(status));
 140                 return ERROR_JTAG_DEVICE_ERROR;
 141         }
 142         *bytes_written = dw_bytes_written;
 143         return ERROR_OK;
 144 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 145         int retval;
 146 #ifdef _DEBUG_JTAG_IO_
 147         LOG_DEBUG("usb_blaster_buf_write %02X (%d)", buf[0], size);
 148 #endif
 149         retval = ftdi_write_data(&ftdic, buf, size);
 150         if (retval < 0)
 151         {
 152                 *bytes_written = 0;
 153                 LOG_ERROR("ftdi_write_data: %s", ftdi_get_error_string(&ftdic));
 154                 return ERROR_JTAG_DEVICE_ERROR;
 155         }
 156         *bytes_written = retval;
 157         return ERROR_OK;
 158 #endif
 159 }
 160
 161 static int
 162 usb_blaster_buf_read(uint8_t *buf, unsigned size, uint32_t *bytes_read)
 163 {
 164 #if BUILD_USB_BLASTER_FTD2XX == 1
 165         DWORD dw_bytes_read;
 166         FT_STATUS status;
 167
 168         status = FT_Read(ftdih, buf, size, &dw_bytes_read);
 169         if (status != FT_OK)
 170         {
 171                 *bytes_read = dw_bytes_read;
 172                 LOG_ERROR("FT_Read returned: %s", ftd2xx_status_string(status));
 173                 return ERROR_JTAG_DEVICE_ERROR;
 174         }
 175 #ifdef _DEBUG_JTAG_IO_
 176         LOG_DEBUG("usb_blaster_buf_read %02X (%" PRIu32 ")", buf[0], dw_bytes_read);
 177 #endif
 178         *bytes_read = dw_bytes_read;
 179         return ERROR_OK;
 180
 181 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 182         int retval;
 183         int timeout = 100;
 184
 185         *bytes_read = 0;
 186         while ((*bytes_read < size) && timeout--)
 187         {
 188                 retval = ftdi_read_data(&ftdic, buf + *bytes_read,
 189                                 size - *bytes_read);
 190                 if (retval < 0)
 191                 {
 192                         *bytes_read = 0;
 193                         LOG_ERROR("ftdi_read_data: %s",
 194                                         ftdi_get_error_string(&ftdic));
 195                         return ERROR_JTAG_DEVICE_ERROR;
 196                 }
 197                 *bytes_read += retval;
 198         }
 199 #ifdef _DEBUG_JTAG_IO_
 200         LOG_DEBUG("usb_blaster_buf_read %02X (%d)", buf[0], *bytes_read);
 201 #endif
 202         return ERROR_OK;
 203 #endif
 204 }
 205
 206 /* The following code doesn't fully utilize the possibilities of the
 207  * USB-Blaster. It only buffers data up to the maximum packet size of 64 bytes.
 208  *
 209  * Actually, the USB-Blaster offers a byte-shift mode to transmit up to 504 data
 210  * bits (bidirectional) in a single USB packet. A header byte has to be sent as
 211  * the first byte in a packet with the following meaning:
 212  *
 213  *   Bit 7 (0x80): Must be set to indicate byte-shift mode.
 214  *   Bit 6 (0x40): If set, the USB-Blaster will also read data, not just write.
 215  *   Bit 5..0:     Define the number N of following bytes
 216  *
 217  * All N following bytes will then be clocked out serially on TDI. If Bit 6 was
 218  * set, it will afterwards return N bytes with TDO data read while clocking out
 219  * the TDI data. LSB of the first byte after the header byte will appear first
 220  * on TDI.
 221  */
 222
 223 /* Simple bit banging mode:
 224  *
 225  *   Bit 7 (0x80): Must be zero (see byte-shift mode above)
 226  *   Bit 6 (0x40): If set, you will receive a byte indicating the state of TDO
 227  *                 in return.
 228  *   Bit 5 (0x20): Output Enable/LED.
 229  *   Bit 4 (0x10): TDI Output.
 230  *   Bit 3 (0x08): nCS Output (not used in JTAG mode).
 231  *   Bit 2 (0x04): nCE Output (not used in JTAG mode).
 232  *   Bit 1 (0x02): TMS Output.
 233  *   Bit 0 (0x01): TCK Output.
 234  *
 235  * For transmitting a single data bit, you need to write two bytes. Up to 64
 236  * bytes can be combined in a single USB packet.
 237  * It isn't possible to read a data without transmitting data.
 238  */
 239
 240 #define TCK                     (1 << 0)
 241 #define TMS                     (1 << 1)
 242 #define NCE                     (1 << 2)
 243 #define NCS                     (1 << 3)
 244 #define TDI                     (1 << 4)
 245 #define LED                     (1 << 5)
 246 #define READ            (1 << 6)
 247 #define SHMODE          (1 << 7)
 248 #define OTHERS          ((1 << 2) | (1 << 3) | (1 << 5))
 249
 250 #define READ_TDO        (1 << 0)
 251
 252 static void usb_blaster_write_databuffer(uint8_t* buf, uint16_t len)
 253 {
 254         uint32_t bytes_written;
 255         usb_blaster_buf_write(buf, len, &bytes_written);
 256         out_count = 0;
 257 #ifdef _DEBUG_JTAG_IO_
 258         LOG_DEBUG("---- WROTE %d",bytes_written);
 259 #endif
 260 }
 261
 262 static void usb_blaster_addtowritebuffer(uint8_t value, bool forcewrite)
 263 {
 264         out_buffer[out_count] = value;
 265         out_count += 1;
 266         if(out_count == BUF_LEN || forcewrite)
 267                 usb_blaster_write_databuffer(out_buffer, out_count);
 268 }
 269
 270 static int usb_blaster_read_data(void)
 271 {
 272         int status;
 273         uint8_t buf[1];
 274         uint32_t bytes_read;
 275
 276         if(out_count > 0)
 277                 usb_blaster_write_databuffer(out_buffer, out_count);
 278
 279         out_value |= READ;
 280         usb_blaster_addtowritebuffer(out_value, true);
 281         out_value &= ~READ;
 282
 283         status = usb_blaster_buf_read(buf, 1, &bytes_read);
 284         if (status < 0)
 285                 return 0;
 286
 287         return !!(buf[0] & READ_TDO);
 288 }
 289
 290 static void usb_blaster_write(int tck, int tms, int tdi)
 291 {
 292 #ifdef _DEBUG_JTAG_IO_
 293         LOG_DEBUG("---- usb_blaster_write(%d,%d,%d)", tck, tms, tdi);
 294 #endif
 295         out_value &= ~(TCK | TMS | TDI);
 296         if (tck)
 297                 out_value |= TCK;
 298         if (tms)
 299                 out_value |= TMS;
 300         if (tdi)
 301                 out_value |= TDI;
 302
 303         usb_blaster_addtowritebuffer(out_value, false);
 304 }
 305
 306 static int usb_blaster_speed(int speed)
 307 {
 308 #if BUILD_USB_BLASTER_FTD2XX == 1
 309         LOG_DEBUG("TODO: usb_blaster_speed() isn't implemented for libftd2xx!");
 310 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 311         LOG_DEBUG("TODO: usb_blaster_speed() isn't optimally implemented!");
 312
 313         /* TODO: libftdi's ftdi_set_baudrate chokes on high rates, use lowlevel
 314          * usb function instead! And additionally allow user to throttle.
 315          */
 316         if (ftdi_set_baudrate(&ftdic, 3000000 / 4) < 0)
 317         {
 318                 LOG_ERROR("Can't set baud rate to max: %s",
 319                         ftdi_get_error_string(&ftdic));
 320                 return ERROR_JTAG_DEVICE_ERROR;
 321         };
 322 #endif
 323
 324         return ERROR_OK;
 325 }
 326
 327 static void usb_blaster_reset(int trst, int srst)
 328 {
 329         LOG_DEBUG("TODO: usb_blaster_reset(%d,%d) isn't implemented!",
 330                         trst, srst);
 331 }
 332
 333 static void usb_blaster_blink(int state)
 334 {
 335         out_value = 0x00;
 336         if(state)
 337                 out_value |= LED;
 338
 339         usb_blaster_addtowritebuffer(out_value, true);
 340 }
 341
 342 static struct bitbang_interface usb_blaster_bitbang = {
 343         .read = usb_blaster_read_data,
 344         .write = usb_blaster_write,
 345         .reset = usb_blaster_reset,
 346         .blink = usb_blaster_blink,
 347 };
 348
 349 static int usb_blaster_init(void)
 350 {
 351         uint8_t latency_timer;
 352
 353 #if BUILD_USB_BLASTER_FTD2XX == 1
 354         FT_STATUS status;
 355 #endif
 356
 357 #if BUILD_USB_BLASTER_FTD2XX == 1
 358         LOG_DEBUG("'usb_blaster' interface using FTD2XX");
 359 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 360         LOG_DEBUG("'usb_blaster' interface using libftdi");
 361 #endif
 362
 363 #if BUILD_USB_BLASTER_FTD2XX == 1
 364         /* Open by device description */
 365         if (usb_blaster_device_desc == NULL)
 366         {
 367                 LOG_WARNING("no usb_blaster device description specified, "
 368                                         "using default 'USB-Blaster'");
 369                 usb_blaster_device_desc = "USB-Blaster";
 370         }
 371
 372 #if IS_WIN32 == 0
 373         /* Add non-standard Vid/Pid to the linux driver */
 374         status = FT_SetVIDPID(usb_blaster_vid, usb_blaster_pid);
 375         if (status != FT_OK)
 376         {
 377                 LOG_WARNING("couldn't add %4.4x:%4.4x",
 378                         usb_blaster_vid, usb_blaster_pid);
 379         }
 380 #endif
 381
 382         status = FT_OpenEx(usb_blaster_device_desc, FT_OPEN_BY_DESCRIPTION,
 383                         &ftdih);
 384         if (status != FT_OK)
 385         {
 386                 DWORD num_devices;
 387
 388                 LOG_ERROR("unable to open ftdi device: %s",
 389                                 ftd2xx_status_string(status));
 390                 status = FT_ListDevices(&num_devices, NULL,
 391                                 FT_LIST_NUMBER_ONLY);
 392                 if (status == FT_OK)
 393                 {
 394                         char **desc_array = malloc(sizeof(char *)
 395                                                 * (num_devices + 1));
 396                         unsigned int i;
 397
 398                         for (i = 0; i < num_devices; i++)
 399                                 desc_array[i] = malloc(64);
 400                         desc_array[num_devices] = NULL;
 401
 402                         status = FT_ListDevices(desc_array, &num_devices,
 403                                 FT_LIST_ALL | FT_OPEN_BY_DESCRIPTION);
 404
 405                         if (status == FT_OK)
 406                         {
 407                                 LOG_ERROR("ListDevices: %" PRIu32, (uint32_t)num_devices);
 408                                 for (i = 0; i < num_devices; i++)
 409                                         LOG_ERROR("%i: %s", i, desc_array[i]);
 410                         }
 411
 412                         for (i = 0; i < num_devices; i++)
 413                                 free(desc_array[i]);
 414                         free(desc_array);
 415                 }
 416                 else
 417                 {
 418                         printf("ListDevices: NONE\n");
 419                 }
 420                 return ERROR_JTAG_INIT_FAILED;
 421         }
 422
 423         status = FT_SetLatencyTimer(ftdih, 2);
 424         if (status != FT_OK)
 425         {
 426                 LOG_ERROR("unable to set latency timer: %s",
 427                                 ftd2xx_status_string(status));
 428                 return ERROR_JTAG_INIT_FAILED;
 429         }
 430
 431         status = FT_GetLatencyTimer(ftdih, &latency_timer);
 432         if (status != FT_OK)
 433         {
 434                 LOG_ERROR("unable to get latency timer: %s",
 435                                 ftd2xx_status_string(status));
 436                 return ERROR_JTAG_INIT_FAILED;
 437         }
 438         LOG_DEBUG("current latency timer: %i", latency_timer);
 439
 440         status = FT_SetBitMode(ftdih, 0x00, 0);
 441         if (status != FT_OK)
 442         {
 443                 LOG_ERROR("unable to disable bit i/o mode: %s",
 444                                 ftd2xx_status_string(status));
 445                 return ERROR_JTAG_INIT_FAILED;
 446         }
 447 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 448         if (ftdi_init(&ftdic) < 0)
 449                 return ERROR_JTAG_INIT_FAILED;
 450
 451         /* context, vendor id, product id */
 452         if (ftdi_usb_open(&ftdic, usb_blaster_vid, usb_blaster_pid) < 0)
 453         {
 454                 LOG_ERROR("unable to open ftdi device: %s", ftdic.error_str);
 455                 return ERROR_JTAG_INIT_FAILED;
 456         }
 457
 458         if (ftdi_usb_reset(&ftdic) < 0)
 459         {
 460                 LOG_ERROR("unable to reset ftdi device");
 461                 return ERROR_JTAG_INIT_FAILED;
 462         }
 463
 464         if (ftdi_set_latency_timer(&ftdic, 2) < 0)
 465         {
 466                 LOG_ERROR("unable to set latency timer");
 467                 return ERROR_JTAG_INIT_FAILED;
 468         }
 469
 470         if (ftdi_get_latency_timer(&ftdic, &latency_timer) < 0)
 471         {
 472                 LOG_ERROR("unable to get latency timer");
 473                 return ERROR_JTAG_INIT_FAILED;
 474         }
 475         LOG_DEBUG("current latency timer: %u", latency_timer);
 476
 477         ftdi_disable_bitbang(&ftdic);
 478 #endif
 479
 480         bitbang_interface = &usb_blaster_bitbang;
 481
 482 #if 0
 483 #if BUILD_USB_BLASTER_FTD2XX == 1
 484         if ((status = FT_Purge(ftdih, FT_PURGE_RX | FT_PURGE_TX)) != FT_OK)
 485         {
 486                 LOG_ERROR("error purging ftd2xx device: %i", status);
 487                 return ERROR_JTAG_INIT_FAILED;
 488         }
 489 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 490         if (ftdi_usb_purge_buffers(&ftdic) < 0)
 491         {
 492                 LOG_ERROR("ftdi_purge_buffers: %s", ftdic.error_str);
 493                 return ERROR_JTAG_INIT_FAILED;
 494         }
 495 #endif
 496 #endif
 497
 498         return ERROR_OK;
 499 }
 500
 501 static int usb_blaster_quit(void)
 502 {
 503         if(out_count > 0)
 504                 usb_blaster_write_databuffer(out_buffer, out_count);
 505
 506 #if BUILD_USB_BLASTER_FTD2XX == 1
 507         FT_STATUS status;
 508
 509         status = FT_Close(ftdih);
 510 #elif BUILD_USB_BLASTER_LIBFTDI == 1
 511         ftdi_usb_close(&ftdic);
 512         ftdi_deinit(&ftdic);
 513 #endif
 514
 515         return ERROR_OK;
 516 }
 517
 518 COMMAND_HANDLER(usb_blaster_handle_device_desc_command)
 519 {
 520         if (CMD_ARGC == 1)
 521                 usb_blaster_device_desc = strdup(CMD_ARGV[0]);
 522         else
 523                 LOG_ERROR("require exactly one argument to "
 524                                   "usb_blaster_device_desc <description>");
 525
 526         return ERROR_OK;
 527 }
 528
 529 COMMAND_HANDLER(usb_blaster_handle_vid_pid_command)
 530 {
 531         if (CMD_ARGC > 2)
 532         {
 533                 LOG_WARNING("ignoring extra IDs in usb_blaster_vid_pid "
 534                                         "(maximum is 1 pair)");
 535                 CMD_ARGC = 2;
 536         }
 537         if (CMD_ARGC == 2)
 538         {
 539                 COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], usb_blaster_vid);
 540                 COMMAND_PARSE_NUMBER(u16, CMD_ARGV[1], usb_blaster_pid);
 541         }
 542         else
 543                 LOG_WARNING("incomplete usb_blaster_vid_pid configuration");
 544
 545         return ERROR_OK;
 546 }
 547
 548 COMMAND_HANDLER(usb_blaster_handle_pin_command)
 549 {
 550         if (CMD_ARGC == 2)
 551         {
 552                 const char * const pin_name = CMD_ARGV[0];
 553                 uint8_t mask;
 554                 unsigned int state;
 555
 556                 if (!strcmp(pin_name, "pin6"))
 557                         mask = NCE;
 558                 else if (!strcmp(pin_name, "pin8"))
 559                         mask = NCS;
 560                 else
 561                 {
 562                         LOG_ERROR("%s: pin name must be \"pin6\" or \"pin8\"",
 563                                         CMD_NAME);
 564                         return ERROR_COMMAND_SYNTAX_ERROR;
 565                 }
 566
 567                 COMMAND_PARSE_NUMBER(uint, CMD_ARGV[1], state);
 568                 if (state == 0)
 569                 {
 570                         out_value &= ~mask;
 571                         usb_blaster_addtowritebuffer(out_value, true);
 572                 }
 573                 else if (state == 1)
 574                 {
 575                         out_value |= mask;
 576                         usb_blaster_addtowritebuffer(out_value, true);
 577                 }
 578                 else
 579                 {
 580                         LOG_ERROR("%s: pin state must be 0 or 1", CMD_NAME);
 581                         return ERROR_COMMAND_SYNTAX_ERROR;
 582                 }
 583
 584                 return ERROR_OK;
 585         }
 586         else
 587         {
 588                 LOG_ERROR("%s takes exactly two arguments", CMD_NAME);
 589                 return ERROR_COMMAND_SYNTAX_ERROR;
 590         }
 591 }
 592
 593 static const struct command_registration usb_blaster_command_handlers[] = {
 594         {
 595                 .name = "usb_blaster_device_desc",
 596                 .handler = usb_blaster_handle_device_desc_command,
 597                 .mode = COMMAND_CONFIG,
 598                 .help = "set the USB device description of the USB-Blaster",
 599                 .usage = "description-string",
 600         },
 601         {
 602                 .name = "usb_blaster_vid_pid",
 603                 .handler = usb_blaster_handle_vid_pid_command,
 604                 .mode = COMMAND_CONFIG,
 605                 .help = "the vendor ID and product ID of the USB-Blaster",
 606                 .usage = "vid pid",
 607         },
 608         {
 609                 .name = "usb_blaster",
 610                 .handler = usb_blaster_handle_pin_command,
 611                 .mode = COMMAND_ANY,
 612                 .help = "set pin state for the unused GPIO pins",
 613                 .usage = "(pin6|pin8) (0|1)",
 614         },
 615         COMMAND_REGISTRATION_DONE
 616 };
 617
 618 struct jtag_interface usb_blaster_interface = {
 619         .name = "usb_blaster",
 620         .commands = usb_blaster_command_handlers,
 621         .supported = DEBUG_CAP_TMS_SEQ,
 622
 623         .execute_queue = bitbang_execute_queue,
 624
 625         .speed = usb_blaster_speed,
 626         .init = usb_blaster_init,
 627         .quit = usb_blaster_quit,
 628 };