git.gag.com Git - fw/openocd/blob - src/jtag/drivers/cmsis_dap_usb_bulk.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 /***************************************************************************
   4  *   Copyright (C) 2018 by Mickaël Thomas                                  *
   5  *   mickael9@gmail.com                                                    *
   6  *                                                                         *
   7  *   Copyright (C) 2016 by Maksym Hilliaka                                 *
   8  *   oter@frozen-team.com                                                  *
   9  *                                                                         *
  10  *   Copyright (C) 2016 by Phillip Pearson                                 *
  11  *   pp@myelin.co.nz                                                       *
  12  *                                                                         *
  13  *   Copyright (C) 2014 by Paul Fertser                                    *
  14  *   fercerpav@gmail.com                                                   *
  15  *                                                                         *
  16  *   Copyright (C) 2013 by mike brown                                      *
  17  *   mike@theshedworks.org.uk                                              *
  18  *                                                                         *
  19  *   Copyright (C) 2013 by Spencer Oliver                                  *
  20  *   spen@spen-soft.co.uk                                                  *
  21  ***************************************************************************/
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include <helper/system.h>
  28 #include <libusb.h>
  29 #include <helper/log.h>
  30 #include <helper/replacements.h>
  31
  32 #include "cmsis_dap.h"
  33
  34 struct cmsis_dap_backend_data {
  35         struct libusb_context *usb_ctx;
  36         struct libusb_device_handle *dev_handle;
  37         unsigned int ep_out;
  38         unsigned int ep_in;
  39         int interface;
  40 };
  41
  42 static int cmsis_dap_usb_interface = -1;
  43
  44 static void cmsis_dap_usb_close(struct cmsis_dap *dap);
  45 static int cmsis_dap_usb_alloc(struct cmsis_dap *dap, unsigned int pkt_sz);
  46
  47 static int cmsis_dap_usb_open(struct cmsis_dap *dap, uint16_t vids[], uint16_t pids[], const char *serial)
  48 {
  49         int err;
  50         struct libusb_context *ctx;
  51         struct libusb_device **device_list;
  52
  53         err = libusb_init(&ctx);
  54         if (err) {
  55                 LOG_ERROR("libusb initialization failed: %s", libusb_strerror(err));
  56                 return ERROR_FAIL;
  57         }
  58
  59         int num_devices = libusb_get_device_list(ctx, &device_list);
  60         if (num_devices < 0) {
  61                 LOG_ERROR("could not enumerate USB devices: %s", libusb_strerror(num_devices));
  62                 libusb_exit(ctx);
  63                 return ERROR_FAIL;
  64         }
  65
  66         for (int i = 0; i < num_devices; i++) {
  67                 struct libusb_device *dev = device_list[i];
  68                 struct libusb_device_descriptor dev_desc;
  69
  70                 err = libusb_get_device_descriptor(dev, &dev_desc);
  71                 if (err) {
  72                         LOG_ERROR("could not get device descriptor for device %d: %s", i, libusb_strerror(err));
  73                         continue;
  74                 }
  75
  76                 /* Match VID/PID */
  77
  78                 bool id_match = false;
  79                 bool id_filter = vids[0] || pids[0];
  80                 for (int id = 0; vids[id] || pids[id]; id++) {
  81                         id_match = !vids[id] || dev_desc.idVendor == vids[id];
  82                         id_match &= !pids[id] || dev_desc.idProduct == pids[id];
  83
  84                         if (id_match)
  85                                 break;
  86                 }
  87
  88                 if (id_filter && !id_match)
  89                         continue;
  90
  91                 /* Don't continue if we asked for a serial number and the device doesn't have one */
  92                 if (dev_desc.iSerialNumber == 0 && serial && serial[0])
  93                         continue;
  94
  95                 struct libusb_device_handle *dev_handle = NULL;
  96                 err = libusb_open(dev, &dev_handle);
  97                 if (err) {
  98                         /* It's to be expected that most USB devices can't be opened
  99                          * so only report an error if it was explicitly selected
 100                          */
 101                         if (id_filter) {
 102                                 LOG_ERROR("could not open device 0x%04x:0x%04x: %s",
 103                                                 dev_desc.idVendor, dev_desc.idProduct, libusb_strerror(err));
 104                         } else {
 105                                 LOG_DEBUG("could not open device 0x%04x:0x%04x: %s",
 106                                                 dev_desc.idVendor, dev_desc.idProduct, libusb_strerror(err));
 107                         }
 108                         continue;
 109                 }
 110
 111                 /* Match serial number */
 112
 113                 bool serial_match = false;
 114                 char dev_serial[256] = {0};
 115                 if (dev_desc.iSerialNumber > 0) {
 116                         err = libusb_get_string_descriptor_ascii(
 117                                         dev_handle, dev_desc.iSerialNumber,
 118                                         (uint8_t *)dev_serial, sizeof(dev_serial));
 119
 120                         if (err < 0) {
 121                                 const char *msg = "could not read serial number for device 0x%04x:0x%04x: %s";
 122                                 if (serial)
 123                                         LOG_WARNING(msg, dev_desc.idVendor, dev_desc.idProduct,
 124                                                                 libusb_strerror(err));
 125                                 else
 126                                         LOG_DEBUG(msg, dev_desc.idVendor, dev_desc.idProduct,
 127                                                                 libusb_strerror(err));
 128                         } else if (serial && strncmp(dev_serial, serial, sizeof(dev_serial)) == 0) {
 129                                 serial_match = true;
 130                         }
 131                 }
 132
 133                 if (serial && !serial_match) {
 134                         libusb_close(dev_handle);
 135                         continue;
 136                 }
 137
 138                 /* Find the CMSIS-DAP string in product string */
 139
 140                 bool cmsis_dap_in_product_str = false;
 141                 char product_string[256] = {0};
 142                 if (dev_desc.iProduct > 0) {
 143                         err = libusb_get_string_descriptor_ascii(
 144                                         dev_handle, dev_desc.iProduct,
 145                                         (uint8_t *)product_string, sizeof(product_string));
 146                         if (err < 0) {
 147                                 LOG_WARNING("could not read product string for device 0x%04x:0x%04x: %s",
 148                                                 dev_desc.idVendor, dev_desc.idProduct, libusb_strerror(err));
 149                         } else if (strstr(product_string, "CMSIS-DAP")) {
 150                                 LOG_DEBUG("found product string of 0x%04x:0x%04x '%s'",
 151                                                   dev_desc.idVendor, dev_desc.idProduct, product_string);
 152                                 cmsis_dap_in_product_str = true;
 153                         }
 154                 }
 155
 156                 bool device_identified_reliably = cmsis_dap_in_product_str
 157                                                                                         || serial_match || id_match;
 158
 159                 /* Find the CMSIS-DAP interface */
 160
 161                 for (int config = 0; config < dev_desc.bNumConfigurations; config++) {
 162                         struct libusb_config_descriptor *config_desc;
 163                         err = libusb_get_config_descriptor(dev, config, &config_desc);
 164                         if (err) {
 165                                 LOG_ERROR("could not get configuration descriptor %d for device 0x%04x:0x%04x: %s",
 166                                                 config, dev_desc.idVendor, dev_desc.idProduct, libusb_strerror(err));
 167                                 continue;
 168                         }
 169
 170                         LOG_DEBUG("enumerating interfaces of 0x%04x:0x%04x",
 171                                           dev_desc.idVendor, dev_desc.idProduct);
 172                         int config_num = config_desc->bConfigurationValue;
 173                         const struct libusb_interface_descriptor *intf_desc_candidate = NULL;
 174                         const struct libusb_interface_descriptor *intf_desc_found = NULL;
 175
 176                         for (int interface = 0; interface < config_desc->bNumInterfaces; interface++) {
 177                                 const struct libusb_interface_descriptor *intf_desc = &config_desc->interface[interface].altsetting[0];
 178                                 int interface_num = intf_desc->bInterfaceNumber;
 179
 180                                 /* Skip this interface if another one was requested explicitly */
 181                                 if (cmsis_dap_usb_interface != -1 && cmsis_dap_usb_interface != interface_num)
 182                                         continue;
 183
 184                                 /* CMSIS-DAP v2 spec says:
 185                                  *
 186                                  * CMSIS-DAP with default V2 configuration uses WinUSB and is therefore faster.
 187                                  * Optionally support for streaming SWO trace is provided via an additional USB endpoint.
 188                                  *
 189                                  * The WinUSB configuration requires custom class support with the interface setting
 190                                  *     Class Code: 0xFF (Vendor specific)
 191                                  *     Subclass: 0x00
 192                                  *     Protocol code: 0x00
 193                                  *
 194                                  * Depending on the configuration it uses the following USB endpoints which should be configured
 195                                  * in the interface descriptor in this order:
 196                                  *  - Endpoint 1: Bulk Out – used for commands received from host PC.
 197                                  *  - Endpoint 2: Bulk In – used for responses send to host PC.
 198                                  *  - Endpoint 3: Bulk In (optional) – used for streaming SWO trace (if enabled with SWO_STREAM).
 199                                  */
 200
 201                                 /* Search for "CMSIS-DAP" in the interface string */
 202                                 bool cmsis_dap_in_interface_str = false;
 203                                 if (intf_desc->iInterface != 0) {
 204
 205                                         char interface_str[256] = {0};
 206
 207                                         err = libusb_get_string_descriptor_ascii(
 208                                                         dev_handle, intf_desc->iInterface,
 209                                                         (uint8_t *)interface_str, sizeof(interface_str));
 210                                         if (err < 0) {
 211                                                 LOG_DEBUG("could not read interface string %d for device 0x%04x:0x%04x: %s",
 212                                                                   intf_desc->iInterface,
 213                                                                   dev_desc.idVendor, dev_desc.idProduct,
 214                                                                   libusb_strerror(err));
 215                                         } else if (strstr(interface_str, "CMSIS-DAP")) {
 216                                                 cmsis_dap_in_interface_str = true;
 217                                                 LOG_DEBUG("found interface %d string '%s'",
 218                                                                   interface_num, interface_str);
 219                                         }
 220                                 }
 221
 222                                 /* Bypass the following check if this interface was explicitly requested. */
 223                                 if (cmsis_dap_usb_interface == -1) {
 224                                         if (!cmsis_dap_in_product_str && !cmsis_dap_in_interface_str)
 225                                                 continue;
 226                                 }
 227
 228                                 /* check endpoints */
 229                                 if (intf_desc->bNumEndpoints < 2) {
 230                                         LOG_DEBUG("skipping interface %d, has only %d endpoints",
 231                                                           interface_num, intf_desc->bNumEndpoints);
 232                                         continue;
 233                                 }
 234
 235                                 if ((intf_desc->endpoint[0].bmAttributes & 3) != LIBUSB_TRANSFER_TYPE_BULK ||
 236                                                 (intf_desc->endpoint[0].bEndpointAddress & 0x80) != LIBUSB_ENDPOINT_OUT) {
 237                                         LOG_DEBUG("skipping interface %d, endpoint[0] is not bulk out",
 238                                                           interface_num);
 239                                         continue;
 240                                 }
 241
 242                                 if ((intf_desc->endpoint[1].bmAttributes & 3) != LIBUSB_TRANSFER_TYPE_BULK ||
 243                                                 (intf_desc->endpoint[1].bEndpointAddress & 0x80) != LIBUSB_ENDPOINT_IN) {
 244                                         LOG_DEBUG("skipping interface %d, endpoint[1] is not bulk in",
 245                                                           interface_num);
 246                                         continue;
 247                                 }
 248
 249                                 /* We can rely on the interface is really CMSIS-DAP if
 250                                  * - we've seen CMSIS-DAP in the interface string
 251                                  * - config asked explicitly for an interface number
 252                                  * - the device has only one interface
 253                                  * The later two cases should be honored only if we know
 254                                  * we are on the right device */
 255                                 bool intf_identified_reliably = cmsis_dap_in_interface_str
 256                                                         || (device_identified_reliably &&
 257                                                                         (cmsis_dap_usb_interface != -1
 258                                                                          || config_desc->bNumInterfaces == 1));
 259
 260                                 if (intf_desc->bInterfaceClass != LIBUSB_CLASS_VENDOR_SPEC ||
 261                                                 intf_desc->bInterfaceSubClass != 0 || intf_desc->bInterfaceProtocol != 0) {
 262                                         /* If the interface is reliably identified
 263                                          * then we need not insist on setting USB class, subclass and protocol
 264                                          * exactly as the specification requires.
 265                                          * At least KitProg3 uses class 0 contrary to the specification */
 266                                         if (intf_identified_reliably) {
 267                                                 LOG_WARNING("Using CMSIS-DAPv2 interface %d with wrong class %" PRId8
 268                                                                   " subclass %" PRId8 " or protocol %" PRId8,
 269                                                                   interface_num,
 270                                                                   intf_desc->bInterfaceClass,
 271                                                                   intf_desc->bInterfaceSubClass,
 272                                                                   intf_desc->bInterfaceProtocol);
 273                                         } else {
 274                                                 LOG_DEBUG("skipping interface %d, class %" PRId8
 275                                                                   " subclass %" PRId8 " protocol %" PRId8,
 276                                                                   interface_num,
 277                                                                   intf_desc->bInterfaceClass,
 278                                                                   intf_desc->bInterfaceSubClass,
 279                                                                   intf_desc->bInterfaceProtocol);
 280                                                 continue;
 281
 282                                         }
 283                                 }
 284
 285                                 if (intf_identified_reliably) {
 286                                         /* That's the one! */
 287                                         intf_desc_found = intf_desc;
 288                                         break;
 289                                 }
 290
 291                                 if (!intf_desc_candidate && device_identified_reliably) {
 292                                         /* This interface looks suitable for CMSIS-DAP. Store the pointer to it
 293                                          * and keep searching for another one with CMSIS-DAP in interface string */
 294                                         intf_desc_candidate = intf_desc;
 295                                 }
 296                         }
 297
 298                         if (!intf_desc_found) {
 299                                 /* We were not able to identify reliably which interface is CMSIS-DAP.
 300                                  * Let's use the first suitable if we found one */
 301                                 intf_desc_found = intf_desc_candidate;
 302                         }
 303
 304                         if (!intf_desc_found) {
 305                                 libusb_free_config_descriptor(config_desc);
 306                                 continue;
 307                         }
 308
 309                         /* We've chosen an interface, connect to it */
 310                         int interface_num = intf_desc_found->bInterfaceNumber;
 311                         int packet_size = intf_desc_found->endpoint[0].wMaxPacketSize;
 312                         int ep_out = intf_desc_found->endpoint[0].bEndpointAddress;
 313                         int ep_in = intf_desc_found->endpoint[1].bEndpointAddress;
 314
 315                         libusb_free_config_descriptor(config_desc);
 316                         libusb_free_device_list(device_list, true);
 317
 318                         LOG_INFO("Using CMSIS-DAPv2 interface with VID:PID=0x%04x:0x%04x, serial=%s",
 319                                         dev_desc.idVendor, dev_desc.idProduct, dev_serial);
 320
 321                         int current_config;
 322                         err = libusb_get_configuration(dev_handle, &current_config);
 323                         if (err) {
 324                                 LOG_ERROR("could not find current configuration: %s", libusb_strerror(err));
 325                                 libusb_close(dev_handle);
 326                                 libusb_exit(ctx);
 327                                 return ERROR_FAIL;
 328                         }
 329
 330                         if (config_num != current_config) {
 331                                 err = libusb_set_configuration(dev_handle, config_num);
 332                                 if (err) {
 333                                         LOG_ERROR("could not set configuration: %s", libusb_strerror(err));
 334                                         libusb_close(dev_handle);
 335                                         libusb_exit(ctx);
 336                                         return ERROR_FAIL;
 337                                 }
 338                         }
 339
 340                         err = libusb_claim_interface(dev_handle, interface_num);
 341                         if (err)
 342                                 LOG_WARNING("could not claim interface: %s", libusb_strerror(err));
 343
 344                         dap->bdata = malloc(sizeof(struct cmsis_dap_backend_data));
 345                         if (!dap->bdata) {
 346                                 LOG_ERROR("unable to allocate memory");
 347                                 libusb_release_interface(dev_handle, interface_num);
 348                                 libusb_close(dev_handle);
 349                                 libusb_exit(ctx);
 350                                 return ERROR_FAIL;
 351                         }
 352
 353                         dap->packet_size = packet_size;
 354                         dap->packet_buffer_size = packet_size;
 355                         dap->bdata->usb_ctx = ctx;
 356                         dap->bdata->dev_handle = dev_handle;
 357                         dap->bdata->ep_out = ep_out;
 358                         dap->bdata->ep_in = ep_in;
 359                         dap->bdata->interface = interface_num;
 360
 361                         dap->packet_buffer = malloc(dap->packet_buffer_size);
 362                         if (!dap->packet_buffer) {
 363                                 LOG_ERROR("unable to allocate memory");
 364                                 cmsis_dap_usb_close(dap);
 365                                 return ERROR_FAIL;
 366                         }
 367
 368                         dap->command = dap->packet_buffer;
 369                         dap->response = dap->packet_buffer;
 370
 371                         return ERROR_OK;
 372                 }
 373
 374                 libusb_close(dev_handle);
 375         }
 376
 377         libusb_free_device_list(device_list, true);
 378
 379         libusb_exit(ctx);
 380         return ERROR_FAIL;
 381 }
 382
 383 static void cmsis_dap_usb_close(struct cmsis_dap *dap)
 384 {
 385         libusb_release_interface(dap->bdata->dev_handle, dap->bdata->interface);
 386         libusb_close(dap->bdata->dev_handle);
 387         libusb_exit(dap->bdata->usb_ctx);
 388         free(dap->bdata);
 389         dap->bdata = NULL;
 390         free(dap->packet_buffer);
 391         dap->packet_buffer = NULL;
 392 }
 393
 394 static int cmsis_dap_usb_read(struct cmsis_dap *dap, int timeout_ms)
 395 {
 396         int transferred = 0;
 397         int err;
 398
 399         err = libusb_bulk_transfer(dap->bdata->dev_handle, dap->bdata->ep_in,
 400                                                         dap->packet_buffer, dap->packet_size, &transferred, timeout_ms);
 401         if (err) {
 402                 if (err == LIBUSB_ERROR_TIMEOUT) {
 403                         return ERROR_TIMEOUT_REACHED;
 404                 } else {
 405                         LOG_ERROR("error reading data: %s", libusb_strerror(err));
 406                         return ERROR_FAIL;
 407                 }
 408         }
 409
 410         memset(&dap->packet_buffer[transferred], 0, dap->packet_buffer_size - transferred);
 411
 412         return transferred;
 413 }
 414
 415 static int cmsis_dap_usb_write(struct cmsis_dap *dap, int txlen, int timeout_ms)
 416 {
 417         int transferred = 0;
 418         int err;
 419
 420         /* skip the first byte that is only used by the HID backend */
 421         err = libusb_bulk_transfer(dap->bdata->dev_handle, dap->bdata->ep_out,
 422                                                         dap->packet_buffer, txlen, &transferred, timeout_ms);
 423         if (err) {
 424                 if (err == LIBUSB_ERROR_TIMEOUT) {
 425                         return ERROR_TIMEOUT_REACHED;
 426                 } else {
 427                         LOG_ERROR("error writing data: %s", libusb_strerror(err));
 428                         return ERROR_FAIL;
 429                 }
 430         }
 431
 432         return transferred;
 433 }
 434
 435 static int cmsis_dap_usb_alloc(struct cmsis_dap *dap, unsigned int pkt_sz)
 436 {
 437         uint8_t *buf = malloc(pkt_sz);
 438         if (!buf) {
 439                 LOG_ERROR("unable to allocate CMSIS-DAP packet buffer");
 440                 return ERROR_FAIL;
 441         }
 442
 443         dap->packet_buffer = buf;
 444         dap->packet_size = pkt_sz;
 445         dap->packet_buffer_size = pkt_sz;
 446
 447         dap->command = dap->packet_buffer;
 448         dap->response = dap->packet_buffer;
 449
 450         return ERROR_OK;
 451 }
 452
 453 COMMAND_HANDLER(cmsis_dap_handle_usb_interface_command)
 454 {
 455         if (CMD_ARGC == 1)
 456                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], cmsis_dap_usb_interface);
 457         else
 458                 LOG_ERROR("expected exactly one argument to cmsis_dap_usb_interface <interface_number>");
 459
 460         return ERROR_OK;
 461 }
 462
 463 const struct command_registration cmsis_dap_usb_subcommand_handlers[] = {
 464         {
 465                 .name = "interface",
 466                 .handler = &cmsis_dap_handle_usb_interface_command,
 467                 .mode = COMMAND_CONFIG,
 468                 .help = "set the USB interface number to use (for USB bulk backend only)",
 469                 .usage = "<interface_number>",
 470         },
 471         COMMAND_REGISTRATION_DONE
 472 };
 473
 474 const struct cmsis_dap_backend cmsis_dap_usb_backend = {
 475         .name = "usb_bulk",
 476         .open = cmsis_dap_usb_open,
 477         .close = cmsis_dap_usb_close,
 478         .read = cmsis_dap_usb_read,
 479         .write = cmsis_dap_usb_write,
 480         .packet_buffer_alloc = cmsis_dap_usb_alloc,
 481 };