src/hardware/fx2lafw/protocol.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
   5  * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <config.h>
  22 #include <glib.h>
  23 #include <glib/gstdio.h>
  24 #include "protocol.h"
  25
  26 #pragma pack(push, 1)
  27
  28 struct version_info {
  29         uint8_t major;
  30         uint8_t minor;
  31 };
  32
  33 struct cmd_start_acquisition {
  34         uint8_t flags;
  35         uint8_t sample_delay_h;
  36         uint8_t sample_delay_l;
  37 };
  38
  39 #pragma pack(pop)
  40
  41 #define USB_TIMEOUT 100
  42
  43 static int command_get_fw_version(libusb_device_handle *devhdl,
  44                                   struct version_info *vi)
  45 {
  46         int ret;
  47
  48         ret = libusb_control_transfer(devhdl, LIBUSB_REQUEST_TYPE_VENDOR |
  49                 LIBUSB_ENDPOINT_IN, CMD_GET_FW_VERSION, 0x0000, 0x0000,
  50                 (unsigned char *)vi, sizeof(struct version_info), USB_TIMEOUT);
  51
  52         if (ret < 0) {
  53                 sr_err("Unable to get version info: %s.",
  54                        libusb_error_name(ret));
  55                 return SR_ERR;
  56         }
  57
  58         return SR_OK;
  59 }
  60
  61 static int command_get_revid_version(struct sr_dev_inst *sdi, uint8_t *revid)
  62 {
  63         struct sr_usb_dev_inst *usb = sdi->conn;
  64         libusb_device_handle *devhdl = usb->devhdl;
  65         int ret;
  66
  67         ret = libusb_control_transfer(devhdl, LIBUSB_REQUEST_TYPE_VENDOR |
  68                 LIBUSB_ENDPOINT_IN, CMD_GET_REVID_VERSION, 0x0000, 0x0000,
  69                 revid, 1, USB_TIMEOUT);
  70
  71         if (ret < 0) {
  72                 sr_err("Unable to get REVID: %s.", libusb_error_name(ret));
  73                 return SR_ERR;
  74         }
  75
  76         return SR_OK;
  77 }
  78
  79 static int command_start_acquisition(const struct sr_dev_inst *sdi)
  80 {
  81         struct dev_context *devc;
  82         struct sr_usb_dev_inst *usb;
  83         uint64_t samplerate;
  84         struct cmd_start_acquisition cmd;
  85         int delay, ret;
  86
  87         devc = sdi->priv;
  88         usb = sdi->conn;
  89         samplerate = devc->cur_samplerate;
  90
  91         /* Compute the sample rate. */
  92         if (devc->sample_wide && samplerate > MAX_16BIT_SAMPLE_RATE) {
  93                 sr_err("Unable to sample at %" PRIu64 "Hz "
  94                        "when collecting 16-bit samples.", samplerate);
  95                 return SR_ERR;
  96         }
  97
  98         delay = 0;
  99         cmd.flags = cmd.sample_delay_h = cmd.sample_delay_l = 0;
 100         if ((SR_MHZ(48) % samplerate) == 0) {
 101                 cmd.flags = CMD_START_FLAGS_CLK_48MHZ;
 102                 delay = SR_MHZ(48) / samplerate - 1;
 103                 if (delay > MAX_SAMPLE_DELAY)
 104                         delay = 0;
 105         }
 106
 107         if (delay == 0 && (SR_MHZ(30) % samplerate) == 0) {
 108                 cmd.flags = CMD_START_FLAGS_CLK_30MHZ;
 109                 delay = SR_MHZ(30) / samplerate - 1;
 110         }
 111
 112         sr_dbg("GPIF delay = %d, clocksource = %sMHz.", delay,
 113                 (cmd.flags & CMD_START_FLAGS_CLK_48MHZ) ? "48" : "30");
 114
 115         if (delay < 0 || delay > MAX_SAMPLE_DELAY) {
 116                 sr_err("Unable to sample at %" PRIu64 "Hz.", samplerate);
 117                 return SR_ERR;
 118         }
 119
 120         cmd.sample_delay_h = (delay >> 8) & 0xff;
 121         cmd.sample_delay_l = delay & 0xff;
 122
 123         /* Select the sampling width. */
 124         cmd.flags |= devc->sample_wide ? CMD_START_FLAGS_SAMPLE_16BIT :
 125                 CMD_START_FLAGS_SAMPLE_8BIT;
 126         /* Enable CTL2 clock. */
 127         cmd.flags |= (g_slist_length(devc->enabled_analog_channels) > 0) ? CMD_START_FLAGS_CLK_CTL2 : 0;
 128
 129         /* Send the control message. */
 130         ret = libusb_control_transfer(usb->devhdl, LIBUSB_REQUEST_TYPE_VENDOR |
 131                         LIBUSB_ENDPOINT_OUT, CMD_START, 0x0000, 0x0000,
 132                         (unsigned char *)&cmd, sizeof(cmd), USB_TIMEOUT);
 133         if (ret < 0) {
 134                 sr_err("Unable to send start command: %s.",
 135                        libusb_error_name(ret));
 136                 return SR_ERR;
 137         }
 138
 139         return SR_OK;
 140 }
 141
 142 SR_PRIV int fx2lafw_dev_open(struct sr_dev_inst *sdi, struct sr_dev_driver *di)
 143 {
 144         libusb_device **devlist;
 145         struct sr_usb_dev_inst *usb;
 146         struct libusb_device_descriptor des;
 147         struct dev_context *devc;
 148         struct drv_context *drvc;
 149         struct version_info vi;
 150         int ret = SR_ERR, i, device_count;
 151         uint8_t revid;
 152         char connection_id[64];
 153
 154         drvc = di->context;
 155         devc = sdi->priv;
 156         usb = sdi->conn;
 157
 158         device_count = libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
 159         if (device_count < 0) {
 160                 sr_err("Failed to get device list: %s.",
 161                        libusb_error_name(device_count));
 162                 return SR_ERR;
 163         }
 164
 165         for (i = 0; i < device_count; i++) {
 166                 libusb_get_device_descriptor(devlist[i], &des);
 167
 168                 if (des.idVendor != devc->profile->vid
 169                     || des.idProduct != devc->profile->pid)
 170                         continue;
 171
 172                 if ((sdi->status == SR_ST_INITIALIZING) ||
 173                                 (sdi->status == SR_ST_INACTIVE)) {
 174                         /*
 175                          * Check device by its physical USB bus/port address.
 176                          */
 177                         if (usb_get_port_path(devlist[i], connection_id, sizeof(connection_id)) < 0)
 178                                 continue;
 179
 180                         if (strcmp(sdi->connection_id, connection_id))
 181                                 /* This is not the one. */
 182                                 continue;
 183                 }
 184
 185                 if (!(ret = libusb_open(devlist[i], &usb->devhdl))) {
 186                         if (usb->address == 0xff)
 187                                 /*
 188                                  * First time we touch this device after FW
 189                                  * upload, so we don't know the address yet.
 190                                  */
 191                                 usb->address = libusb_get_device_address(devlist[i]);
 192                 } else {
 193                         sr_err("Failed to open device: %s.",
 194                                libusb_error_name(ret));
 195                         ret = SR_ERR;
 196                         break;
 197                 }
 198
 199                 if (libusb_has_capability(LIBUSB_CAP_SUPPORTS_DETACH_KERNEL_DRIVER)) {
 200                         if (libusb_kernel_driver_active(usb->devhdl, USB_INTERFACE) == 1) {
 201                                 if ((ret = libusb_detach_kernel_driver(usb->devhdl, USB_INTERFACE)) < 0) {
 202                                         sr_err("Failed to detach kernel driver: %s.",
 203                                                 libusb_error_name(ret));
 204                                         ret = SR_ERR;
 205                                         break;
 206                                 }
 207                         }
 208                 }
 209
 210                 ret = command_get_fw_version(usb->devhdl, &vi);
 211                 if (ret != SR_OK) {
 212                         sr_err("Failed to get firmware version.");
 213                         break;
 214                 }
 215
 216                 ret = command_get_revid_version(sdi, &revid);
 217                 if (ret != SR_OK) {
 218                         sr_err("Failed to get REVID.");
 219                         break;
 220                 }
 221
 222                 /*
 223                  * Changes in major version mean incompatible/API changes, so
 224                  * bail out if we encounter an incompatible version.
 225                  * Different minor versions are OK, they should be compatible.
 226                  */
 227                 if (vi.major != FX2LAFW_REQUIRED_VERSION_MAJOR) {
 228                         sr_err("Expected firmware version %d.x, "
 229                                "got %d.%d.", FX2LAFW_REQUIRED_VERSION_MAJOR,
 230                                vi.major, vi.minor);
 231                         break;
 232                 }
 233
 234                 sr_info("Opened device on %d.%d (logical) / %s (physical), "
 235                         "interface %d, firmware %d.%d.",
 236                         usb->bus, usb->address, connection_id,
 237                         USB_INTERFACE, vi.major, vi.minor);
 238
 239                 sr_info("Detected REVID=%d, it's a Cypress CY7C68013%s.",
 240                         revid, (revid != 1) ? " (FX2)" : "A (FX2LP)");
 241
 242                 ret = SR_OK;
 243
 244                 break;
 245         }
 246
 247         libusb_free_device_list(devlist, 1);
 248
 249         return ret;
 250 }
 251
 252 SR_PRIV struct dev_context *fx2lafw_dev_new(void)
 253 {
 254         struct dev_context *devc;
 255
 256         devc = g_malloc0(sizeof(struct dev_context));
 257         devc->profile = NULL;
 258         devc->channel_names = NULL;
 259         devc->fw_updated = 0;
 260         devc->cur_samplerate = 0;
 261         devc->limit_frames = 1;
 262         devc->limit_samples = 0;
 263         devc->capture_ratio = 0;
 264         devc->sample_wide = FALSE;
 265         devc->num_frames = 0;
 266         devc->stl = NULL;
 267
 268         return devc;
 269 }
 270
 271 SR_PRIV void fx2lafw_abort_acquisition(struct dev_context *devc)
 272 {
 273         int i;
 274
 275         devc->acq_aborted = TRUE;
 276
 277         for (i = devc->num_transfers - 1; i >= 0; i--) {
 278                 if (devc->transfers[i])
 279                         libusb_cancel_transfer(devc->transfers[i]);
 280         }
 281 }
 282
 283 static void finish_acquisition(struct sr_dev_inst *sdi)
 284 {
 285         struct dev_context *devc;
 286
 287         devc = sdi->priv;
 288
 289         std_session_send_df_end(sdi);
 290
 291         usb_source_remove(sdi->session, devc->ctx);
 292
 293         devc->num_transfers = 0;
 294         g_free(devc->transfers);
 295
 296         /* Free the deinterlace buffers if we had them. */
 297         if (g_slist_length(devc->enabled_analog_channels) > 0) {
 298                 g_free(devc->logic_buffer);
 299                 g_free(devc->analog_buffer);
 300         }
 301
 302         if (devc->stl) {
 303                 soft_trigger_logic_free(devc->stl);
 304                 devc->stl = NULL;
 305         }
 306 }
 307
 308 static void free_transfer(struct libusb_transfer *transfer)
 309 {
 310         struct sr_dev_inst *sdi;
 311         struct dev_context *devc;
 312         unsigned int i;
 313
 314         sdi = transfer->user_data;
 315         devc = sdi->priv;
 316
 317         g_free(transfer->buffer);
 318         transfer->buffer = NULL;
 319         libusb_free_transfer(transfer);
 320
 321         for (i = 0; i < devc->num_transfers; i++) {
 322                 if (devc->transfers[i] == transfer) {
 323                         devc->transfers[i] = NULL;
 324                         break;
 325                 }
 326         }
 327
 328         devc->submitted_transfers--;
 329         if (devc->submitted_transfers == 0)
 330                 finish_acquisition(sdi);
 331 }
 332
 333 static void resubmit_transfer(struct libusb_transfer *transfer)
 334 {
 335         int ret;
 336
 337         if ((ret = libusb_submit_transfer(transfer)) == LIBUSB_SUCCESS)
 338                 return;
 339
 340         sr_err("%s: %s", __func__, libusb_error_name(ret));
 341         free_transfer(transfer);
 342
 343 }
 344
 345 static void mso_send_data_proc(struct sr_dev_inst *sdi,
 346         uint8_t *data, size_t length, size_t sample_width)
 347 {
 348         size_t i;
 349         struct dev_context *devc;
 350         struct sr_datafeed_analog analog;
 351         struct sr_analog_encoding encoding;
 352         struct sr_analog_meaning meaning;
 353         struct sr_analog_spec spec;
 354
 355         (void)sample_width;
 356
 357         devc = sdi->priv;
 358
 359         length /= 2;
 360
 361         /* Send the logic */
 362         for (i = 0; i < length; i++) {
 363                 devc->logic_buffer[i] = data[i * 2];
 364                 /* Rescale to -10V - +10V from 0-255. */
 365                 devc->analog_buffer[i] = (data[i * 2 + 1] - 128.0f) / 12.8f;
 366         };
 367
 368         const struct sr_datafeed_logic logic = {
 369                 .length = length,
 370                 .unitsize = 1,
 371                 .data = devc->logic_buffer
 372         };
 373
 374         const struct sr_datafeed_packet logic_packet = {
 375                 .type = SR_DF_LOGIC,
 376                 .payload = &logic
 377         };
 378
 379         sr_session_send(sdi, &logic_packet);
 380
 381         sr_analog_init(&analog, &encoding, &meaning, &spec, 2);
 382         analog.meaning->channels = devc->enabled_analog_channels;
 383         analog.meaning->mq = SR_MQ_VOLTAGE;
 384         analog.meaning->unit = SR_UNIT_VOLT;
 385         analog.meaning->mqflags = 0 /* SR_MQFLAG_DC */;
 386         analog.num_samples = length;
 387         analog.data = devc->analog_buffer;
 388
 389         const struct sr_datafeed_packet analog_packet = {
 390                 .type = SR_DF_ANALOG,
 391                 .payload = &analog
 392         };
 393
 394         sr_session_send(sdi, &analog_packet);
 395 }
 396
 397 static void la_send_data_proc(struct sr_dev_inst *sdi,
 398         uint8_t *data, size_t length, size_t sample_width)
 399 {
 400         const struct sr_datafeed_logic logic = {
 401                 .length = length,
 402                 .unitsize = sample_width,
 403                 .data = data
 404         };
 405
 406         const struct sr_datafeed_packet packet = {
 407                 .type = SR_DF_LOGIC,
 408                 .payload = &logic
 409         };
 410
 411         sr_session_send(sdi, &packet);
 412 }
 413
 414 static void LIBUSB_CALL receive_transfer(struct libusb_transfer *transfer)
 415 {
 416         struct sr_dev_inst *sdi;
 417         struct dev_context *devc;
 418         gboolean packet_has_error = FALSE;
 419         unsigned int num_samples;
 420         int trigger_offset, cur_sample_count, unitsize, processed_samples;
 421         int pre_trigger_samples;
 422
 423         sdi = transfer->user_data;
 424         devc = sdi->priv;
 425
 426         /*
 427          * If acquisition has already ended, just free any queued up
 428          * transfer that come in.
 429          */
 430         if (devc->acq_aborted) {
 431                 free_transfer(transfer);
 432                 return;
 433         }
 434
 435         sr_dbg("receive_transfer(): status %s received %d bytes.",
 436                 libusb_error_name(transfer->status), transfer->actual_length);
 437
 438         /* Save incoming transfer before reusing the transfer struct. */
 439         unitsize = devc->sample_wide ? 2 : 1;
 440         cur_sample_count = transfer->actual_length / unitsize;
 441         processed_samples = 0;
 442
 443         switch (transfer->status) {
 444         case LIBUSB_TRANSFER_NO_DEVICE:
 445                 fx2lafw_abort_acquisition(devc);
 446                 free_transfer(transfer);
 447                 return;
 448         case LIBUSB_TRANSFER_COMPLETED:
 449         case LIBUSB_TRANSFER_TIMED_OUT: /* We may have received some data though. */
 450                 break;
 451         default:
 452                 packet_has_error = TRUE;
 453                 break;
 454         }
 455
 456         if (transfer->actual_length == 0 || packet_has_error) {
 457                 devc->empty_transfer_count++;
 458                 if (devc->empty_transfer_count > MAX_EMPTY_TRANSFERS) {
 459                         /*
 460                          * The FX2 gave up. End the acquisition, the frontend
 461                          * will work out that the samplecount is short.
 462                          */
 463                         fx2lafw_abort_acquisition(devc);
 464                         free_transfer(transfer);
 465                 } else {
 466                         resubmit_transfer(transfer);
 467                 }
 468                 return;
 469         } else {
 470                 devc->empty_transfer_count = 0;
 471         }
 472
 473 check_trigger:
 474         if (devc->trigger_fired) {
 475                 if (!devc->limit_samples || devc->sent_samples < devc->limit_samples) {
 476                         /* Send the incoming transfer to the session bus. */
 477                         num_samples = cur_sample_count - processed_samples;
 478                         if (devc->limit_samples && devc->sent_samples + num_samples > devc->limit_samples)
 479                                 num_samples = devc->limit_samples - devc->sent_samples;
 480
 481                         devc->send_data_proc(sdi, (uint8_t *)transfer->buffer + processed_samples * unitsize,
 482                                 num_samples * unitsize, unitsize);
 483                         devc->sent_samples += num_samples;
 484                         processed_samples += num_samples;
 485                 }
 486         } else {
 487                 trigger_offset = soft_trigger_logic_check(devc->stl,
 488                         transfer->buffer + processed_samples * unitsize,
 489                         transfer->actual_length - processed_samples * unitsize,
 490                         &pre_trigger_samples);
 491                 if (trigger_offset > -1) {
 492                         std_session_send_df_frame_begin(sdi);
 493                         devc->sent_samples += pre_trigger_samples;
 494                         num_samples = cur_sample_count - processed_samples - trigger_offset;
 495                         if (devc->limit_samples &&
 496                                         devc->sent_samples + num_samples > devc->limit_samples)
 497                                 num_samples = devc->limit_samples - devc->sent_samples;
 498
 499                         devc->send_data_proc(sdi, (uint8_t *)transfer->buffer
 500                                         + processed_samples * unitsize
 501                                         + trigger_offset * unitsize,
 502                                         num_samples * unitsize, unitsize);
 503                         devc->sent_samples += num_samples;
 504                         processed_samples += trigger_offset + num_samples;
 505
 506                         devc->trigger_fired = TRUE;
 507                 }
 508         }
 509
 510         const int frame_ended = devc->limit_samples && (devc->sent_samples >= devc->limit_samples);
 511         const int final_frame = devc->limit_frames && (devc->num_frames >= (devc->limit_frames - 1));
 512
 513         if (frame_ended) {
 514                 devc->num_frames++;
 515                 devc->sent_samples = 0;
 516                 devc->trigger_fired = FALSE;
 517                 std_session_send_df_frame_end(sdi);
 518
 519                 /* There may be another trigger in the remaining data, go back and check for it */
 520                 if (processed_samples < cur_sample_count) {
 521                         /* Reset the trigger stage */
 522                         if (devc->stl)
 523                                 devc->stl->cur_stage = 0;
 524                         else {
 525                                 std_session_send_df_frame_begin(sdi);
 526                                 devc->trigger_fired = TRUE;
 527                         }
 528                         if (!final_frame)
 529                                 goto check_trigger;
 530                 }
 531         }
 532         if (frame_ended && final_frame) {
 533                 fx2lafw_abort_acquisition(devc);
 534                 free_transfer(transfer);
 535         } else
 536                 resubmit_transfer(transfer);
 537 }
 538
 539 static int configure_channels(const struct sr_dev_inst *sdi)
 540 {
 541         struct dev_context *devc;
 542         const GSList *l;
 543         int p;
 544         struct sr_channel *ch;
 545         uint32_t channel_mask = 0, num_analog = 0;
 546
 547         devc = sdi->priv;
 548
 549         g_slist_free(devc->enabled_analog_channels);
 550         devc->enabled_analog_channels = NULL;
 551
 552         for (l = sdi->channels, p = 0; l; l = l->next, p++) {
 553                 ch = l->data;
 554                 if ((p <= NUM_CHANNELS) && (ch->type == SR_CHANNEL_ANALOG)
 555                                 && (ch->enabled)) {
 556                         num_analog++;
 557                         devc->enabled_analog_channels =
 558                             g_slist_append(devc->enabled_analog_channels, ch);
 559                 } else {
 560                         channel_mask |= ch->enabled << p;
 561                 }
 562         }
 563
 564         /*
 565          * Use wide sampling if either any of the LA channels 8..15 is enabled,
 566          * and/or at least one analog channel is enabled.
 567          */
 568         devc->sample_wide = channel_mask > 0xff || num_analog > 0;
 569
 570         return SR_OK;
 571 }
 572
 573 static unsigned int to_bytes_per_ms(unsigned int samplerate)
 574 {
 575         return samplerate / 1000;
 576 }
 577
 578 static size_t get_buffer_size(struct dev_context *devc)
 579 {
 580         size_t s;
 581
 582         /*
 583          * The buffer should be large enough to hold 10ms of data and
 584          * a multiple of 512.
 585          */
 586         s = 10 * to_bytes_per_ms(devc->cur_samplerate);
 587         return (s + 511) & ~511;
 588 }
 589
 590 static unsigned int get_number_of_transfers(struct dev_context *devc)
 591 {
 592         unsigned int n;
 593
 594         /* Total buffer size should be able to hold about 500ms of data. */
 595         n = (500 * to_bytes_per_ms(devc->cur_samplerate) /
 596                 get_buffer_size(devc));
 597
 598         if (n > NUM_SIMUL_TRANSFERS)
 599                 return NUM_SIMUL_TRANSFERS;
 600
 601         return n;
 602 }
 603
 604 static unsigned int get_timeout(struct dev_context *devc)
 605 {
 606         size_t total_size;
 607         unsigned int timeout;
 608
 609         total_size = get_buffer_size(devc) *
 610                         get_number_of_transfers(devc);
 611         timeout = total_size / to_bytes_per_ms(devc->cur_samplerate);
 612         return timeout + timeout / 4; /* Leave a headroom of 25% percent. */
 613 }
 614
 615 static int receive_data(int fd, int revents, void *cb_data)
 616 {
 617         struct timeval tv;
 618         struct drv_context *drvc;
 619
 620         (void)fd;
 621         (void)revents;
 622
 623         drvc = (struct drv_context *)cb_data;
 624
 625         tv.tv_sec = tv.tv_usec = 0;
 626         libusb_handle_events_timeout(drvc->sr_ctx->libusb_ctx, &tv);
 627
 628         return TRUE;
 629 }
 630
 631 static int start_transfers(const struct sr_dev_inst *sdi)
 632 {
 633         struct dev_context *devc;
 634         struct sr_usb_dev_inst *usb;
 635         struct sr_trigger *trigger;
 636         struct libusb_transfer *transfer;
 637         unsigned int i, num_transfers;
 638         int timeout, ret;
 639         unsigned char *buf;
 640         size_t size;
 641
 642         devc = sdi->priv;
 643         usb = sdi->conn;
 644
 645         devc->sent_samples = 0;
 646         devc->acq_aborted = FALSE;
 647         devc->empty_transfer_count = 0;
 648
 649         if ((trigger = sr_session_trigger_get(sdi->session))) {
 650                 int pre_trigger_samples = 0;
 651                 if (devc->limit_samples > 0)
 652                         pre_trigger_samples = (devc->capture_ratio * devc->limit_samples) / 100;
 653                 devc->stl = soft_trigger_logic_new(sdi, trigger, pre_trigger_samples);
 654                 if (!devc->stl)
 655                         return SR_ERR_MALLOC;
 656                 devc->trigger_fired = FALSE;
 657         } else {
 658                 std_session_send_df_frame_begin(sdi);
 659                 devc->trigger_fired = TRUE;
 660         }
 661
 662         num_transfers = get_number_of_transfers(devc);
 663
 664         size = get_buffer_size(devc);
 665         devc->submitted_transfers = 0;
 666
 667         devc->transfers = g_try_malloc0(sizeof(*devc->transfers) * num_transfers);
 668         if (!devc->transfers) {
 669                 sr_err("USB transfers malloc failed.");
 670                 return SR_ERR_MALLOC;
 671         }
 672
 673         timeout = get_timeout(devc);
 674         devc->num_transfers = num_transfers;
 675         for (i = 0; i < num_transfers; i++) {
 676                 if (!(buf = g_try_malloc(size))) {
 677                         sr_err("USB transfer buffer malloc failed.");
 678                         return SR_ERR_MALLOC;
 679                 }
 680                 transfer = libusb_alloc_transfer(0);
 681                 libusb_fill_bulk_transfer(transfer, usb->devhdl,
 682                                 2 | LIBUSB_ENDPOINT_IN, buf, size,
 683                                 receive_transfer, (void *)sdi, timeout);
 684                 sr_info("submitting transfer: %d", i);
 685                 if ((ret = libusb_submit_transfer(transfer)) != 0) {
 686                         sr_err("Failed to submit transfer: %s.",
 687                                libusb_error_name(ret));
 688                         libusb_free_transfer(transfer);
 689                         g_free(buf);
 690                         fx2lafw_abort_acquisition(devc);
 691                         return SR_ERR;
 692                 }
 693                 devc->transfers[i] = transfer;
 694                 devc->submitted_transfers++;
 695         }
 696
 697         /*
 698          * If this device has analog channels and at least one of them is
 699          * enabled, use mso_send_data_proc() to properly handle the analog
 700          * data. Otherwise use la_send_data_proc().
 701          */
 702         if (g_slist_length(devc->enabled_analog_channels) > 0)
 703                 devc->send_data_proc = mso_send_data_proc;
 704         else
 705                 devc->send_data_proc = la_send_data_proc;
 706
 707         std_session_send_df_header(sdi);
 708
 709         return SR_OK;
 710 }
 711
 712 SR_PRIV int fx2lafw_start_acquisition(const struct sr_dev_inst *sdi)
 713 {
 714         struct sr_dev_driver *di;
 715         struct drv_context *drvc;
 716         struct dev_context *devc;
 717         int timeout, ret;
 718         size_t size;
 719
 720         di = sdi->driver;
 721         drvc = di->context;
 722         devc = sdi->priv;
 723
 724         devc->ctx = drvc->sr_ctx;
 725         devc->num_frames = 0;
 726         devc->sent_samples = 0;
 727         devc->empty_transfer_count = 0;
 728         devc->acq_aborted = FALSE;
 729
 730         if (configure_channels(sdi) != SR_OK) {
 731                 sr_err("Failed to configure channels.");
 732                 return SR_ERR;
 733         }
 734
 735         timeout = get_timeout(devc);
 736         usb_source_add(sdi->session, devc->ctx, timeout, receive_data, drvc);
 737
 738         size = get_buffer_size(devc);
 739         /* Prepare for analog sampling. */
 740         if (g_slist_length(devc->enabled_analog_channels) > 0) {
 741                 /* We need a buffer half the size of a transfer. */
 742                 devc->logic_buffer = g_try_malloc(size / 2);
 743                 devc->analog_buffer = g_try_malloc(
 744                         sizeof(float) * size / 2);
 745         }
 746         start_transfers(sdi);
 747         if ((ret = command_start_acquisition(sdi)) != SR_OK) {
 748                 fx2lafw_abort_acquisition(devc);
 749                 return ret;
 750         }
 751
 752         return SR_OK;
 753 }