hardware/ikalogic-scanalogic2/protocol.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2013 Marc Schink <sigrok-dev@marcschink.de>
   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 3 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, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "protocol.h"
  21
  22 extern struct sr_dev_driver ikalogic_scanalogic2_driver_info;
  23 static struct sr_dev_driver *di = &ikalogic_scanalogic2_driver_info;
  24
  25 extern uint64_t sl2_samplerates[NUM_SAMPLERATES];
  26
  27 static void stop_acquisition(struct sr_dev_inst *sdi)
  28 {
  29         struct drv_context *drvc = sdi->driver->priv;
  30         struct dev_context *devc;
  31         struct sr_datafeed_packet packet;
  32
  33         devc = sdi->priv;
  34
  35         /* Remove USB file descriptors from polling. */
  36         usb_source_remove(drvc->sr_ctx);
  37
  38         packet.type = SR_DF_END;
  39         sr_session_send(devc->cb_data, &packet);
  40
  41         sdi->status = SR_ST_ACTIVE;
  42 }
  43
  44 static void abort_acquisition(struct sr_dev_inst *sdi)
  45 {
  46         struct drv_context *drvc = sdi->driver->priv;
  47         struct dev_context *devc;
  48         struct sr_datafeed_packet packet;
  49
  50         devc = sdi->priv;
  51
  52         /* Remove USB file descriptors from polling. */
  53         usb_source_remove(drvc->sr_ctx);
  54
  55         packet.type = SR_DF_END;
  56         sr_session_send(devc->cb_data, &packet);
  57
  58         sdi->driver->dev_close(sdi);
  59 }
  60
  61 static void buffer_sample_data(const struct sr_dev_inst *sdi)
  62 {
  63         struct dev_context *devc;
  64         unsigned int offset, packet_length;
  65
  66         devc = sdi->priv;
  67
  68         if (devc->channels[devc->channel]->enabled) {
  69                 offset = devc->sample_packet * PACKET_NUM_SAMPLE_BYTES;
  70
  71                 /*
  72                  * Determine the packet length to ensure that the last packet
  73                  * will not exceed the buffer size.
  74                  */
  75                 packet_length = MIN(PACKET_NUM_SAMPLE_BYTES,
  76                         MAX_DEV_SAMPLE_BYTES - offset);
  77
  78                 /*
  79                  * Skip the first 4 bytes of the source buffer because they
  80                  * contain channel and packet information only.
  81                  */
  82                 memcpy(devc->sample_buffer[devc->channel] + offset,
  83                         devc->xfer_data_in + 4, packet_length);
  84         }
  85 }
  86
  87 static void process_sample_data(const struct sr_dev_inst *sdi)
  88 {
  89         struct dev_context *devc;
  90         struct sr_datafeed_packet packet;
  91         struct sr_datafeed_logic logic;
  92         uint8_t i, j, tmp, buffer[PACKET_NUM_SAMPLES], *ptr[NUM_PROBES];
  93         uint16_t offset, n = 0;
  94         int8_t k;
  95
  96         devc = sdi->priv;
  97         offset = devc->sample_packet * PACKET_NUM_SAMPLE_BYTES;
  98
  99         /*
 100          * Array of pointers to the sample data of all channels up to the last
 101          * enabled one for an uniform access to them. Note that the currently
 102          * received samples always belong to the last enabled channel.
 103          */
 104         for (i = 0; i < devc->num_enabled_channels - 1; i++)
 105                 ptr[i] = devc->sample_buffer[devc->channel_map[i]] + offset;
 106
 107         /*
 108          * Skip the first 4 bytes of the buffer because they contain channel
 109          * and packet information only.
 110          */
 111         ptr[i] = devc->xfer_data_in + 4;
 112
 113         for (i = 0; i < PACKET_NUM_SAMPLE_BYTES; i++) {
 114                 /* Stop processing if all requested samples are processed. */
 115                 if (devc->samples_processed == devc->limit_samples)
 116                         break;
 117
 118                 k = 7;
 119
 120                 if (devc->samples_processed == 0) {
 121                         /*
 122                          * Adjust the position of the first sample to be
 123                          * processed because possibly more samples than
 124                          * necessary might have been acquired. This is because
 125                          * the number of acquired samples is always rounded up
 126                          * to a multiple of 8.
 127                          */
 128                         k = k - (devc->pre_trigger_bytes * 8) +
 129                                 devc->pre_trigger_samples;
 130
 131                         sr_dbg("Start processing at sample: %d.", 7 - k);
 132
 133                         /*
 134                          * Send the trigger before the first sample is
 135                          * processed if no pre trigger samples were calculated
 136                          * through the capture ratio.
 137                          */
 138                         if (devc->trigger_type != TRIGGER_TYPE_NONE &&
 139                                         devc->pre_trigger_samples == 0) {
 140                                 packet.type = SR_DF_TRIGGER;
 141                                 sr_session_send(devc->cb_data, &packet);
 142                         }
 143                 }
 144
 145                 for (; k >= 0; k--) {
 146                         /*
 147                          * Stop processing if all requested samples are
 148                          * processed.
 149                          */
 150                         if (devc->samples_processed == devc->limit_samples)
 151                                 break;
 152
 153                         buffer[n] = 0;
 154
 155                         /*
 156                          * Extract the current sample for each enabled channel
 157                          * and store them in the buffer.
 158                          */
 159                         for (j = 0; j < devc->num_enabled_channels; j++) {
 160                                 tmp = (ptr[j][i] & (1 << k)) >> k;
 161                                 buffer[n] |= tmp << devc->channel_map[j];
 162                         }
 163
 164                         n++;
 165                         devc->samples_processed++;
 166
 167                         /*
 168                          * Send all processed samples and the trigger if the
 169                          * number of processed samples reaches the calculated
 170                          * number of pre trigger samples.
 171                          */
 172                         if (devc->samples_processed == devc->pre_trigger_samples &&
 173                                         devc->trigger_type != TRIGGER_TYPE_NONE) {
 174                                 packet.type = SR_DF_LOGIC;
 175                                 packet.payload = &logic;
 176                                 logic.length = n;
 177                                 logic.unitsize = 1;
 178                                 logic.data = buffer;
 179                                 sr_session_send(devc->cb_data, &packet);
 180
 181                                 packet.type = SR_DF_TRIGGER;
 182                                 sr_session_send(devc->cb_data, &packet);
 183
 184                                 n = 0;
 185                         }
 186                 }
 187         }
 188
 189         if (n > 0) {
 190                 packet.type = SR_DF_LOGIC;
 191                 packet.payload = &logic;
 192                 logic.length = n;
 193                 logic.unitsize = 1;
 194                 logic.data = buffer;
 195                 sr_session_send(devc->cb_data, &packet);
 196         }
 197 }
 198
 199 SR_PRIV int ikalogic_scanalogic2_receive_data(int fd, int revents, void *cb_data)
 200 {
 201         struct sr_dev_inst *sdi;
 202         struct dev_context *devc;
 203         struct drv_context *drvc;
 204         struct timeval tv;
 205         int64_t current_time, time_elapsed;
 206         int ret = 0;
 207
 208         (void)fd;
 209         (void)revents;
 210
 211         if (!(sdi = cb_data))
 212                 return TRUE;
 213
 214         if (!(devc = sdi->priv))
 215                 return TRUE;
 216
 217         drvc = di->priv;
 218         current_time = g_get_monotonic_time();
 219
 220         if (devc->state == STATE_WAIT_DATA_READY &&
 221                         !devc->wait_data_ready_locked) {
 222                 time_elapsed = current_time - devc->wait_data_ready_time;
 223
 224                 /*
 225                  * Check here for stopping in addition to the transfer
 226                  * callback functions to avoid waiting until the
 227                  * WAIT_DATA_READY_INTERVAL has expired.
 228                  */
 229                 if (sdi->status == SR_ST_STOPPING) {
 230                         if (!devc->stopping_in_progress) {
 231                                 devc->next_state = STATE_RESET_AND_IDLE;
 232                                 devc->stopping_in_progress = TRUE;
 233                                 ret = libusb_submit_transfer(devc->xfer_in);
 234                         }
 235                 } else if (time_elapsed >= WAIT_DATA_READY_INTERVAL) {
 236                         devc->wait_data_ready_locked = TRUE;
 237                         ret = libusb_submit_transfer(devc->xfer_in);
 238                 }
 239         }
 240
 241         if (ret != 0) {
 242                 sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
 243                 abort_acquisition(sdi);
 244                 return TRUE;
 245         }
 246
 247         tv.tv_sec = 0;
 248         tv.tv_usec = 0;
 249
 250         libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx, &tv,
 251                 NULL);
 252
 253         /* Check if an error occurred on a transfer. */
 254         if (devc->transfer_error)
 255                 abort_acquisition(sdi);
 256
 257         return TRUE;
 258 }
 259
 260 SR_PRIV void sl2_receive_transfer_in( struct libusb_transfer *transfer)
 261 {
 262         struct sr_dev_inst *sdi;
 263         struct dev_context *devc;
 264         uint8_t last_channel;
 265         int ret = 0;
 266
 267         sdi = transfer->user_data;
 268         devc = sdi->priv;
 269
 270         if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
 271                 sr_err("Transfer to device failed: %i.", transfer->status);
 272                 devc->transfer_error = TRUE;
 273                 return;
 274         }
 275
 276         if (sdi->status == SR_ST_STOPPING && !devc->stopping_in_progress) {
 277                 devc->next_state = STATE_RESET_AND_IDLE;
 278                 devc->stopping_in_progress = TRUE;
 279
 280                 if (libusb_submit_transfer(devc->xfer_in) != 0) {
 281                         sr_err("Submit transfer failed: %s.",
 282                                 libusb_error_name(ret));
 283                         devc->transfer_error = TRUE;
 284                 }
 285
 286                 return;
 287         }
 288
 289         if (devc->state != devc->next_state)
 290                 sr_spew("State changed from %i to %i.",
 291                         devc->state, devc->next_state);
 292         devc->state = devc->next_state;
 293
 294         if (devc->state == STATE_WAIT_DATA_READY) {
 295                 /* Check if the received data are a valid device status. */
 296                 if (devc->xfer_data_in[0] == 0x05) {
 297                         if (devc->xfer_data_in[1] == STATUS_WAITING_FOR_TRIGGER)
 298                                 sr_dbg("Waiting for trigger.");
 299                         else if (devc->xfer_data_in[1] == STATUS_SAMPLING)
 300                                 sr_dbg("Sampling in progress.");
 301                 }
 302
 303                 /*
 304                  * Check if the received data are a valid device status and the
 305                  * sample data are ready.
 306                  */
 307                 if (devc->xfer_data_in[0] == 0x05 &&
 308                                 devc->xfer_data_in[1] == STATUS_DATA_READY) {
 309                         devc->next_state = STATE_RECEIVE_DATA;
 310                         ret = libusb_submit_transfer(transfer);
 311                 } else {
 312                         devc->wait_data_ready_locked = FALSE;
 313                         devc->wait_data_ready_time = g_get_monotonic_time();
 314                 }
 315         } else if (devc->state == STATE_RECEIVE_DATA) {
 316                 last_channel = devc->channel_map[devc->num_enabled_channels - 1];
 317
 318                 if (devc->channel < last_channel) {
 319                         buffer_sample_data(sdi);
 320                 } else if (devc->channel == last_channel) {
 321                         process_sample_data(sdi);
 322                 } else {
 323                         /*
 324                          * Stop acquisition because all samples of enabled
 325                          * channels are processed.
 326                          */
 327                         devc->next_state = STATE_RESET_AND_IDLE;
 328                 }
 329
 330                 devc->sample_packet++;
 331                 devc->sample_packet %= devc->num_sample_packets;
 332
 333                 if (devc->sample_packet == 0)
 334                         devc->channel++;
 335
 336                 ret = libusb_submit_transfer(transfer);
 337         } else if (devc->state == STATE_RESET_AND_IDLE) {
 338                 /* Check if the received data are a valid device status. */
 339                 if (devc->xfer_data_in[0] == 0x05) {
 340                         if (devc->xfer_data_in[1] == STATUS_DEVICE_READY) {
 341                                 devc->next_state = STATE_IDLE;
 342                                 devc->xfer_data_out[0] = CMD_IDLE;
 343                         } else {
 344                                 devc->next_state = STATE_WAIT_DEVICE_READY;
 345                                 devc->xfer_data_out[0] = CMD_RESET;
 346                         }
 347
 348                         ret = libusb_submit_transfer(devc->xfer_out);
 349                 } else {
 350                         /*
 351                          * The received device status is invalid which
 352                          * indicates that the device is not ready to accept
 353                          * commands. Request a new device status until a valid
 354                          * device status is received.
 355                          */
 356                         ret = libusb_submit_transfer(transfer);
 357                 }
 358         } else if (devc->state == STATE_WAIT_DEVICE_READY) {
 359                 /* Check if the received data are a valid device status. */
 360                 if (devc->xfer_data_in[0] == 0x05) {
 361                         if (devc->xfer_data_in[1] == STATUS_DEVICE_READY) {
 362                                 devc->next_state = STATE_IDLE;
 363                                 devc->xfer_data_out[0] = CMD_IDLE;
 364                         } else {
 365                                 /*
 366                                  * The received device status is valid but the
 367                                  * device is not ready. Probably the device did
 368                                  * not recognize the last reset. Reset the
 369                                  * device again.
 370                                  */
 371                                 devc->xfer_data_out[0] = CMD_RESET;
 372                         }
 373
 374                         ret = libusb_submit_transfer(devc->xfer_out);
 375                 } else {
 376                         /*
 377                          * The device is not ready and therefore not able to
 378                          * change to the idle state. Request a new device
 379                          * status until the device is ready.
 380                          */
 381                         ret = libusb_submit_transfer(transfer);
 382                 }
 383         }
 384
 385         if (ret != 0) {
 386                 sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
 387                 devc->transfer_error = TRUE;
 388         }
 389 }
 390
 391 SR_PRIV void sl2_receive_transfer_out( struct libusb_transfer *transfer)
 392 {
 393         struct sr_dev_inst *sdi;
 394         struct dev_context *devc;
 395         int ret = 0;
 396
 397         sdi = transfer->user_data;
 398         devc = sdi->priv;
 399
 400         if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
 401                 sr_err("Transfer to device failed: %i.", transfer->status);
 402                 devc->transfer_error = TRUE;
 403                 return;
 404         }
 405
 406         if (sdi->status == SR_ST_STOPPING && !devc->stopping_in_progress) {
 407                 devc->next_state = STATE_RESET_AND_IDLE;
 408                 devc->stopping_in_progress = TRUE;
 409
 410                 if (libusb_submit_transfer(devc->xfer_in) != 0) {
 411                         sr_err("Submit transfer failed: %s.",
 412                                 libusb_error_name(ret));
 413
 414                         devc->transfer_error = TRUE;
 415                 }
 416
 417                 return;
 418         }
 419
 420         if (devc->state != devc->next_state)
 421                 sr_spew("State changed from %i to %i.",
 422                         devc->state, devc->next_state);
 423         devc->state = devc->next_state;
 424
 425         if (devc->state == STATE_IDLE) {
 426                 stop_acquisition(sdi);
 427         } else if (devc->state == STATE_SAMPLE) {
 428                 devc->next_state = STATE_WAIT_DATA_READY;
 429                 ret = libusb_submit_transfer(devc->xfer_in);
 430         } else if (devc->state == STATE_WAIT_DEVICE_READY) {
 431                 ret = libusb_submit_transfer(devc->xfer_in);
 432         }
 433
 434         if (ret != 0) {
 435                 sr_err("Submit transfer failed: %s.", libusb_error_name(ret));
 436                 devc->transfer_error = TRUE;
 437         }
 438 }
 439
 440 SR_PRIV int sl2_set_samplerate(const struct sr_dev_inst *sdi,
 441                 uint64_t samplerate)
 442 {
 443         struct dev_context *devc;
 444         unsigned int i;
 445
 446         devc = sdi->priv;
 447
 448         for (i = 0; i < NUM_SAMPLERATES; i++) {
 449                 if (sl2_samplerates[i] == samplerate) {
 450                         devc->samplerate = samplerate;
 451                         devc->samplerate_id = NUM_SAMPLERATES - i - 1;
 452                         return SR_OK;
 453                 }
 454         }
 455
 456         return SR_ERR_ARG;
 457 }
 458
 459 SR_PRIV int sl2_set_limit_samples(const struct sr_dev_inst *sdi,
 460                                   uint64_t limit_samples)
 461 {
 462         struct dev_context *devc;
 463
 464         devc = sdi->priv;
 465
 466         if (limit_samples == 0) {
 467                 sr_err("Invalid number of limit samples: %" PRIu64 ".",
 468                         limit_samples);
 469                 return SR_ERR_ARG;
 470         }
 471
 472         if (limit_samples > MAX_SAMPLES)
 473                 limit_samples = MAX_SAMPLES;
 474
 475         sr_dbg("Limit samples set to %" PRIu64 ".", limit_samples);
 476
 477         devc->limit_samples = limit_samples;
 478
 479         return SR_OK;
 480 }
 481
 482 SR_PRIV void sl2_configure_trigger(const struct sr_dev_inst *sdi)
 483 {
 484         struct dev_context *devc;
 485         struct sr_channel *ch;
 486         uint8_t trigger_type;
 487         int channel_index, num_triggers_anyedge;
 488         char *trigger;
 489         GSList *l;
 490
 491         devc = sdi->priv;
 492
 493         /* Disable the trigger by default. */
 494         devc->trigger_channel = TRIGGER_CHANNEL_0;
 495         devc->trigger_type = TRIGGER_TYPE_NONE;
 496
 497         num_triggers_anyedge = 0;
 498
 499         for (l = sdi->channels, channel_index = 0; l; l = l->next, channel_index++) {
 500                 ch = l->data;
 501                 trigger = ch->trigger;
 502
 503                 if (!trigger || !ch->enabled)
 504                         continue;
 505
 506                 switch (*trigger) {
 507                 case 'r':
 508                         trigger_type = TRIGGER_TYPE_POSEDGE;
 509                         break;
 510                 case 'f':
 511                         trigger_type = TRIGGER_TYPE_NEGEDGE;
 512                         break;
 513                 case 'c':
 514                         trigger_type = TRIGGER_TYPE_ANYEDGE;
 515                         num_triggers_anyedge++;
 516                         break;
 517                 default:
 518                         continue;
 519                 }
 520
 521                 devc->trigger_channel = channel_index + 1;
 522                 devc->trigger_type = trigger_type;
 523         }
 524
 525         /*
 526          * Set trigger to any edge on all channels if the trigger for each
 527          * channel is set to any edge.
 528          */
 529         if (num_triggers_anyedge == NUM_PROBES) {
 530                 devc->trigger_channel = TRIGGER_CHANNEL_ALL;
 531                 devc->trigger_type = TRIGGER_TYPE_ANYEDGE;
 532         }
 533
 534         sr_dbg("Trigger set to channel 0x%02x and type 0x%02x.",
 535                 devc->trigger_channel, devc->trigger_type);
 536 }
 537
 538 SR_PRIV int sl2_set_capture_ratio(const struct sr_dev_inst *sdi,
 539                                   uint64_t capture_ratio)
 540 {
 541         struct dev_context *devc;
 542
 543         devc = sdi->priv;
 544
 545         if (capture_ratio > 100) {
 546                 sr_err("Invalid capture ratio: %" PRIu64 " %%.", capture_ratio);
 547                 return SR_ERR_ARG;
 548         }
 549
 550         sr_info("Capture ratio set to %" PRIu64 " %%.", capture_ratio);
 551
 552         devc->capture_ratio = capture_ratio;
 553
 554         return SR_OK;
 555 }
 556
 557 SR_PRIV int sl2_set_after_trigger_delay(const struct sr_dev_inst *sdi,
 558                                         uint64_t after_trigger_delay)
 559 {
 560         struct dev_context *devc;
 561
 562         devc = sdi->priv;
 563
 564         if (after_trigger_delay > MAX_AFTER_TRIGGER_DELAY) {
 565                 sr_err("Invalid after trigger delay: %" PRIu64 " ms.",
 566                         after_trigger_delay);
 567                 return SR_ERR_ARG;
 568         }
 569
 570         sr_info("After trigger delay set to %" PRIu64 " ms.",
 571                 after_trigger_delay);
 572
 573         devc->after_trigger_delay = after_trigger_delay;
 574
 575         return SR_OK;
 576 }
 577
 578 SR_PRIV void sl2_calculate_trigger_samples(const struct sr_dev_inst *sdi)
 579 {
 580         struct dev_context *devc;
 581         uint64_t pre_trigger_samples, post_trigger_samples;
 582         uint16_t pre_trigger_bytes, post_trigger_bytes;
 583         uint8_t cr;
 584
 585         devc = sdi->priv;
 586         cr = devc->capture_ratio;
 587
 588         /* Ignore the capture ratio if no trigger is enabled. */
 589         if (devc->trigger_type == TRIGGER_TYPE_NONE)
 590                 cr = 0;
 591
 592         pre_trigger_samples = (devc->limit_samples * cr) / 100;
 593         post_trigger_samples = (devc->limit_samples * (100 - cr)) / 100;
 594
 595         /*
 596          * Increase the number of post trigger samples by one to compensate the
 597          * possible loss of a sample through integer rounding.
 598          */
 599         if (pre_trigger_samples + post_trigger_samples != devc->limit_samples)
 600                 post_trigger_samples++;
 601
 602         /*
 603          * The device requires the number of samples in multiples of 8 which
 604          * will also be called sample bytes in the following.
 605          */
 606         pre_trigger_bytes = pre_trigger_samples / 8;
 607         post_trigger_bytes = post_trigger_samples / 8;
 608
 609         /*
 610          * Round up the number of sample bytes to ensure that at least the
 611          * requested number of samples will be acquired. Note that due to this
 612          * rounding the buffer to store these sample bytes needs to be at least
 613          * one sample byte larger than the minimal number of sample bytes
 614          * needed to store the requested samples.
 615          */
 616         if (pre_trigger_samples % 8 != 0)
 617                 pre_trigger_bytes++;
 618
 619         if (post_trigger_samples % 8 != 0)
 620                 post_trigger_bytes++;
 621
 622         sr_info("Pre trigger samples: %" PRIu64 ".", pre_trigger_samples);
 623         sr_info("Post trigger samples: %" PRIu64 ".", post_trigger_samples);
 624         sr_dbg("Pre trigger sample bytes: %" PRIu16 ".", pre_trigger_bytes);
 625         sr_dbg("Post trigger sample bytes: %" PRIu16 ".", post_trigger_bytes);
 626
 627         devc->pre_trigger_samples = pre_trigger_samples;
 628         devc->pre_trigger_bytes = pre_trigger_bytes;
 629         devc->post_trigger_bytes = post_trigger_bytes;
 630 }
 631
 632 SR_PRIV int sl2_get_device_info(struct sr_usb_dev_inst usb,
 633                 struct device_info *dev_info)
 634 {
 635         struct drv_context *drvc;
 636         uint8_t buffer[PACKET_LENGTH];
 637         int ret;
 638
 639         drvc = di->priv;
 640
 641         if (!dev_info)
 642                 return SR_ERR_ARG;
 643
 644         if (sr_usb_open(drvc->sr_ctx->libusb_ctx, &usb) != SR_OK)
 645                 return SR_ERR;
 646
 647         /*
 648          * Determine if a kernel driver is active on this interface and, if so,
 649          * detach it.
 650          */
 651         if (libusb_kernel_driver_active(usb.devhdl, USB_INTERFACE) == 1) {
 652                 ret = libusb_detach_kernel_driver(usb.devhdl,
 653                         USB_INTERFACE);
 654
 655                 if (ret < 0) {
 656                         sr_err("Failed to detach kernel driver: %s.",
 657                                 libusb_error_name(ret));
 658                         libusb_close(usb.devhdl);
 659                         return SR_ERR;
 660                 }
 661         }
 662
 663         ret = libusb_claim_interface(usb.devhdl, USB_INTERFACE);
 664
 665         if (ret) {
 666                 sr_err("Failed to claim interface: %s.",
 667                         libusb_error_name(ret));
 668                 libusb_close(usb.devhdl);
 669                 return SR_ERR;
 670         }
 671
 672         memset(buffer, 0, sizeof(buffer));
 673
 674         /*
 675          * Reset the device to ensure it is in a proper state to request the
 676          * device information.
 677          */
 678         buffer[0] = CMD_RESET;
 679         if ((ret = sl2_transfer_out(usb.devhdl, buffer)) != PACKET_LENGTH) {
 680                 sr_err("Resetting of device failed: %s.",
 681                         libusb_error_name(ret));
 682                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
 683                 libusb_close(usb.devhdl);
 684                 return SR_ERR;
 685         }
 686
 687         buffer[0] = CMD_INFO;
 688         if ((ret = sl2_transfer_out(usb.devhdl, buffer)) != PACKET_LENGTH) {
 689                 sr_err("Requesting of device information failed: %s.",
 690                         libusb_error_name(ret));
 691                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
 692                 libusb_close(usb.devhdl);
 693                 return SR_ERR;
 694         }
 695
 696         if ((ret = sl2_transfer_in(usb.devhdl, buffer)) != PACKET_LENGTH) {
 697                 sr_err("Receiving of device information failed: %s.",
 698                         libusb_error_name(ret));
 699                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
 700                 libusb_close(usb.devhdl);
 701                 return SR_ERR;
 702         }
 703
 704         memcpy(&(dev_info->serial), buffer + 1, sizeof(uint32_t));
 705         dev_info->serial = GUINT32_FROM_LE(dev_info->serial);
 706
 707         dev_info->fw_ver_major = buffer[5];
 708         dev_info->fw_ver_minor = buffer[6];
 709
 710         buffer[0] = CMD_RESET;
 711         if ((ret = sl2_transfer_out(usb.devhdl, buffer)) != PACKET_LENGTH) {
 712                 sr_err("Device reset failed: %s.", libusb_error_name(ret));
 713                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
 714                 libusb_close(usb.devhdl);
 715                 return SR_ERR;
 716         }
 717
 718         /*
 719          * Set the device to idle state. If the device is not in idle state it
 720          * possibly will reset itself after a few seconds without being used
 721          * and thereby close the connection.
 722          */
 723         buffer[0] = CMD_IDLE;
 724         if ((ret = sl2_transfer_out(usb.devhdl, buffer)) != PACKET_LENGTH) {
 725                 sr_err("Failed to set device in idle state: %s.",
 726                         libusb_error_name(ret));
 727                 libusb_release_interface(usb.devhdl, USB_INTERFACE);
 728                 libusb_close(usb.devhdl);
 729                 return SR_ERR;
 730         }
 731
 732         ret = libusb_release_interface(usb.devhdl, USB_INTERFACE);
 733
 734         if (ret < 0) {
 735                 sr_err("Failed to release interface: %s.",
 736                         libusb_error_name(ret));
 737                 libusb_close(usb.devhdl);
 738                 return SR_ERR;
 739         }
 740
 741         libusb_close(usb.devhdl);
 742
 743         return SR_OK;
 744 }
 745
 746 SR_PRIV int sl2_transfer_in(libusb_device_handle *dev_handle, uint8_t *data)
 747 {
 748         return libusb_control_transfer(dev_handle, USB_REQUEST_TYPE_IN,
 749                 USB_HID_GET_REPORT, USB_HID_REPORT_TYPE_FEATURE, USB_INTERFACE,
 750                 (unsigned char *)data, PACKET_LENGTH, USB_TIMEOUT);
 751 }
 752
 753 SR_PRIV int sl2_transfer_out(libusb_device_handle *dev_handle, uint8_t *data)
 754 {
 755         return libusb_control_transfer(dev_handle, USB_REQUEST_TYPE_OUT,
 756                 USB_HID_SET_REPORT, USB_HID_REPORT_TYPE_FEATURE, USB_INTERFACE,
 757                 (unsigned char *)data, PACKET_LENGTH, USB_TIMEOUT);
 758 }