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, 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                         usb_get_port_path(devlist[i], connection_id, sizeof(connection_id));
 178                         if (strcmp(sdi->connection_id, connection_id))
 179                                 /* This is not the one. */
 180                                 continue;
 181                 }
 182
 183                 if (!(ret = libusb_open(devlist[i], &usb->devhdl))) {
 184                         if (usb->address == 0xff)
 185                                 /*
 186                                  * First time we touch this device after FW
 187                                  * upload, so we don't know the address yet.
 188                                  */
 189                                 usb->address = libusb_get_device_address(devlist[i]);
 190                 } else {
 191                         sr_err("Failed to open device: %s.",
 192                                libusb_error_name(ret));
 193                         break;
 194                 }
 195
 196                 if (libusb_has_capability(LIBUSB_CAP_SUPPORTS_DETACH_KERNEL_DRIVER)) {
 197                         if (libusb_kernel_driver_active(usb->devhdl, USB_INTERFACE) == 1) {
 198                                 if ((ret = libusb_detach_kernel_driver(usb->devhdl, USB_INTERFACE)) < 0) {
 199                                         sr_err("Failed to detach kernel driver: %s.",
 200                                                 libusb_error_name(ret));
 201                                         return SR_ERR;
 202                                 }
 203                         }
 204                 }
 205
 206                 ret = command_get_fw_version(usb->devhdl, &vi);
 207                 if (ret != SR_OK) {
 208                         sr_err("Failed to get firmware version.");
 209                         break;
 210                 }
 211
 212                 ret = command_get_revid_version(sdi, &revid);
 213                 if (ret != SR_OK) {
 214                         sr_err("Failed to get REVID.");
 215                         break;
 216                 }
 217
 218                 /*
 219                  * Changes in major version mean incompatible/API changes, so
 220                  * bail out if we encounter an incompatible version.
 221                  * Different minor versions are OK, they should be compatible.
 222                  */
 223                 if (vi.major != FX2LAFW_REQUIRED_VERSION_MAJOR) {
 224                         sr_err("Expected firmware version %d.x, "
 225                                "got %d.%d.", FX2LAFW_REQUIRED_VERSION_MAJOR,
 226                                vi.major, vi.minor);
 227                         break;
 228                 }
 229
 230                 sdi->status = SR_ST_ACTIVE;
 231                 sr_info("Opened device on %d.%d (logical) / %s (physical), "
 232                         "interface %d, firmware %d.%d.",
 233                         usb->bus, usb->address, connection_id,
 234                         USB_INTERFACE, vi.major, vi.minor);
 235
 236                 sr_info("Detected REVID=%d, it's a Cypress CY7C68013%s.",
 237                         revid, (revid != 1) ? " (FX2)" : "A (FX2LP)");
 238
 239                 break;
 240         }
 241         libusb_free_device_list(devlist, 1);
 242
 243         if (sdi->status != SR_ST_ACTIVE)
 244                 return SR_ERR;
 245
 246         return SR_OK;
 247 }
 248
 249 SR_PRIV struct dev_context *fx2lafw_dev_new(void)
 250 {
 251         struct dev_context *devc;
 252
 253         devc = g_malloc0(sizeof(struct dev_context));
 254         devc->profile = NULL;
 255         devc->fw_updated = 0;
 256         devc->cur_samplerate = 0;
 257         devc->limit_samples = 0;
 258         devc->capture_ratio = 0;
 259         devc->sample_wide = FALSE;
 260         devc->stl = NULL;
 261
 262         return devc;
 263 }
 264
 265 SR_PRIV void fx2lafw_abort_acquisition(struct dev_context *devc)
 266 {
 267         int i;
 268
 269         devc->acq_aborted = TRUE;
 270
 271         for (i = devc->num_transfers - 1; i >= 0; i--) {
 272                 if (devc->transfers[i])
 273                         libusb_cancel_transfer(devc->transfers[i]);
 274         }
 275 }
 276
 277 static void finish_acquisition(struct sr_dev_inst *sdi)
 278 {
 279         struct dev_context *devc;
 280
 281         devc = sdi->priv;
 282
 283         std_session_send_df_end(sdi);
 284
 285         usb_source_remove(sdi->session, devc->ctx);
 286
 287         devc->num_transfers = 0;
 288         g_free(devc->transfers);
 289
 290         /* Free the deinterlace buffers if we had them. */
 291         if (g_slist_length(devc->enabled_analog_channels) > 0) {
 292                 g_free(devc->logic_buffer);
 293                 g_free(devc->analog_buffer);
 294         }
 295
 296         if (devc->stl) {
 297                 soft_trigger_logic_free(devc->stl);
 298                 devc->stl = NULL;
 299         }
 300 }
 301
 302 static void free_transfer(struct libusb_transfer *transfer)
 303 {
 304         struct sr_dev_inst *sdi;
 305         struct dev_context *devc;
 306         unsigned int i;
 307
 308         sdi = transfer->user_data;
 309         devc = sdi->priv;
 310
 311         g_free(transfer->buffer);
 312         transfer->buffer = NULL;
 313         libusb_free_transfer(transfer);
 314
 315         for (i = 0; i < devc->num_transfers; i++) {
 316                 if (devc->transfers[i] == transfer) {
 317                         devc->transfers[i] = NULL;
 318                         break;
 319                 }
 320         }
 321
 322         devc->submitted_transfers--;
 323         if (devc->submitted_transfers == 0)
 324                 finish_acquisition(sdi);
 325 }
 326
 327 static void resubmit_transfer(struct libusb_transfer *transfer)
 328 {
 329         int ret;
 330
 331         if ((ret = libusb_submit_transfer(transfer)) == LIBUSB_SUCCESS)
 332                 return;
 333
 334         sr_err("%s: %s", __func__, libusb_error_name(ret));
 335         free_transfer(transfer);
 336
 337 }
 338
 339 static void mso_send_data_proc(struct sr_dev_inst *sdi,
 340         uint8_t *data, size_t length, size_t sample_width)
 341 {
 342         size_t i;
 343         struct dev_context *devc;
 344         struct sr_datafeed_analog analog;
 345         struct sr_analog_encoding encoding;
 346         struct sr_analog_meaning meaning;
 347         struct sr_analog_spec spec;
 348
 349         (void)sample_width;
 350
 351         devc = sdi->priv;
 352
 353         length /= 2;
 354
 355         /* Send the logic */
 356         for (i = 0; i < length; i++) {
 357                 devc->logic_buffer[i] = data[i * 2];
 358                 /* Rescale to -10V - +10V from 0-255. */
 359                 devc->analog_buffer[i] = (data[i * 2 + 1] - 128.0f) / 12.8f;
 360         };
 361
 362         const struct sr_datafeed_logic logic = {
 363                 .length = length,
 364                 .unitsize = 1,
 365                 .data = devc->logic_buffer
 366         };
 367
 368         const struct sr_datafeed_packet logic_packet = {
 369                 .type = SR_DF_LOGIC,
 370                 .payload = &logic
 371         };
 372
 373         sr_session_send(sdi, &logic_packet);
 374
 375         sr_analog_init(&analog, &encoding, &meaning, &spec, 2);
 376         analog.meaning->channels = devc->enabled_analog_channels;
 377         analog.meaning->mq = SR_MQ_VOLTAGE;
 378         analog.meaning->unit = SR_UNIT_VOLT;
 379         analog.meaning->mqflags = 0 /* SR_MQFLAG_DC */;
 380         analog.num_samples = length;
 381         analog.data = devc->analog_buffer;
 382
 383         const struct sr_datafeed_packet analog_packet = {
 384                 .type = SR_DF_ANALOG,
 385                 .payload = &analog
 386         };
 387
 388         sr_session_send(sdi, &analog_packet);
 389 }
 390
 391 static void la_send_data_proc(struct sr_dev_inst *sdi,
 392         uint8_t *data, size_t length, size_t sample_width)
 393 {
 394         const struct sr_datafeed_logic logic = {
 395                 .length = length,
 396                 .unitsize = sample_width,
 397                 .data = data
 398         };
 399
 400         const struct sr_datafeed_packet packet = {
 401                 .type = SR_DF_LOGIC,
 402                 .payload = &logic
 403         };
 404
 405         sr_session_send(sdi, &packet);
 406 }
 407
 408 static void LIBUSB_CALL receive_transfer(struct libusb_transfer *transfer)
 409 {
 410         struct sr_dev_inst *sdi;
 411         struct dev_context *devc;
 412         gboolean packet_has_error = FALSE;
 413         unsigned int num_samples;
 414         int trigger_offset, cur_sample_count, unitsize;
 415         int pre_trigger_samples;
 416
 417         sdi = transfer->user_data;
 418         devc = sdi->priv;
 419
 420         /*
 421          * If acquisition has already ended, just free any queued up
 422          * transfer that come in.
 423          */
 424         if (devc->acq_aborted) {
 425                 free_transfer(transfer);
 426                 return;
 427         }
 428
 429         sr_dbg("receive_transfer(): status %s received %d bytes.",
 430                 libusb_error_name(transfer->status), transfer->actual_length);
 431
 432         /* Save incoming transfer before reusing the transfer struct. */
 433         unitsize = devc->sample_wide ? 2 : 1;
 434         cur_sample_count = transfer->actual_length / unitsize;
 435
 436         switch (transfer->status) {
 437         case LIBUSB_TRANSFER_NO_DEVICE:
 438                 fx2lafw_abort_acquisition(devc);
 439                 free_transfer(transfer);
 440                 return;
 441         case LIBUSB_TRANSFER_COMPLETED:
 442         case LIBUSB_TRANSFER_TIMED_OUT: /* We may have received some data though. */
 443                 break;
 444         default:
 445                 packet_has_error = TRUE;
 446                 break;
 447         }
 448
 449         if (transfer->actual_length == 0 || packet_has_error) {
 450                 devc->empty_transfer_count++;
 451                 if (devc->empty_transfer_count > MAX_EMPTY_TRANSFERS) {
 452                         /*
 453                          * The FX2 gave up. End the acquisition, the frontend
 454                          * will work out that the samplecount is short.
 455                          */
 456                         fx2lafw_abort_acquisition(devc);
 457                         free_transfer(transfer);
 458                 } else {
 459                         resubmit_transfer(transfer);
 460                 }
 461                 return;
 462         } else {
 463                 devc->empty_transfer_count = 0;
 464         }
 465         if (devc->trigger_fired) {
 466                 if (!devc->limit_samples || devc->sent_samples < devc->limit_samples) {
 467                         /* Send the incoming transfer to the session bus. */
 468                         if (devc->limit_samples && devc->sent_samples + cur_sample_count > devc->limit_samples)
 469                                 num_samples = devc->limit_samples - devc->sent_samples;
 470                         else
 471                                 num_samples = cur_sample_count;
 472
 473                         devc->send_data_proc(sdi, (uint8_t *)transfer->buffer,
 474                                 num_samples * unitsize, unitsize);
 475                         devc->sent_samples += num_samples;
 476                 }
 477         } else {
 478                 trigger_offset = soft_trigger_logic_check(devc->stl,
 479                         transfer->buffer, transfer->actual_length, &pre_trigger_samples);
 480                 if (trigger_offset > -1) {
 481                         devc->sent_samples += pre_trigger_samples;
 482                         num_samples = cur_sample_count - trigger_offset;
 483                         if (devc->limit_samples &&
 484                                         num_samples > devc->limit_samples - devc->sent_samples)
 485                                 num_samples = devc->limit_samples - devc->sent_samples;
 486
 487                         devc->send_data_proc(sdi, (uint8_t *)transfer->buffer
 488                                         + trigger_offset * unitsize,
 489                                         num_samples * unitsize, unitsize);
 490                         devc->sent_samples += num_samples;
 491
 492                         devc->trigger_fired = TRUE;
 493                 }
 494         }
 495
 496         if (devc->limit_samples && devc->sent_samples >= devc->limit_samples) {
 497                 fx2lafw_abort_acquisition(devc);
 498                 free_transfer(transfer);
 499         } else
 500                 resubmit_transfer(transfer);
 501 }
 502
 503 static int configure_channels(const struct sr_dev_inst *sdi)
 504 {
 505         struct dev_context *devc;
 506         const GSList *l;
 507         int p;
 508         struct sr_channel *ch;
 509         uint32_t channel_mask = 0, num_analog = 0;
 510
 511         devc = sdi->priv;
 512
 513         g_slist_free(devc->enabled_analog_channels);
 514         devc->enabled_analog_channels = NULL;
 515
 516         for (l = sdi->channels, p = 0; l; l = l->next, p++) {
 517                 ch = l->data;
 518                 if ((p <= NUM_CHANNELS) && (ch->type == SR_CHANNEL_ANALOG)
 519                                 && (ch->enabled)) {
 520                         num_analog++;
 521                         devc->enabled_analog_channels =
 522                             g_slist_append(devc->enabled_analog_channels, ch);
 523                 } else {
 524                         channel_mask |= ch->enabled << p;
 525                 }
 526         }
 527
 528         /*
 529          * Use wide sampling if either any of the LA channels 8..15 is enabled,
 530          * and/or at least one analog channel is enabled.
 531          */
 532         devc->sample_wide = channel_mask > 0xff || num_analog > 0;
 533
 534         return SR_OK;
 535 }
 536
 537 static unsigned int to_bytes_per_ms(unsigned int samplerate)
 538 {
 539         return samplerate / 1000;
 540 }
 541
 542 static size_t get_buffer_size(struct dev_context *devc)
 543 {
 544         size_t s;
 545
 546         /*
 547          * The buffer should be large enough to hold 10ms of data and
 548          * a multiple of 512.
 549          */
 550         s = 10 * to_bytes_per_ms(devc->cur_samplerate);
 551         return (s + 511) & ~511;
 552 }
 553
 554 static unsigned int get_number_of_transfers(struct dev_context *devc)
 555 {
 556         unsigned int n;
 557
 558         /* Total buffer size should be able to hold about 500ms of data. */
 559         n = (500 * to_bytes_per_ms(devc->cur_samplerate) /
 560                 get_buffer_size(devc));
 561
 562         if (n > NUM_SIMUL_TRANSFERS)
 563                 return NUM_SIMUL_TRANSFERS;
 564
 565         return n;
 566 }
 567
 568 static unsigned int get_timeout(struct dev_context *devc)
 569 {
 570         size_t total_size;
 571         unsigned int timeout;
 572
 573         total_size = get_buffer_size(devc) *
 574                         get_number_of_transfers(devc);
 575         timeout = total_size / to_bytes_per_ms(devc->cur_samplerate);
 576         return timeout + timeout / 4; /* Leave a headroom of 25% percent. */
 577 }
 578
 579 static int receive_data(int fd, int revents, void *cb_data)
 580 {
 581         struct timeval tv;
 582         struct drv_context *drvc;
 583
 584         (void)fd;
 585         (void)revents;
 586
 587         drvc = (struct drv_context *)cb_data;
 588
 589         tv.tv_sec = tv.tv_usec = 0;
 590         libusb_handle_events_timeout(drvc->sr_ctx->libusb_ctx, &tv);
 591
 592         return TRUE;
 593 }
 594
 595 static int start_transfers(const struct sr_dev_inst *sdi)
 596 {
 597         struct dev_context *devc;
 598         struct sr_usb_dev_inst *usb;
 599         struct sr_trigger *trigger;
 600         struct libusb_transfer *transfer;
 601         unsigned int i, num_transfers;
 602         int timeout, ret;
 603         unsigned char *buf;
 604         size_t size;
 605
 606         devc = sdi->priv;
 607         usb = sdi->conn;
 608
 609         devc->sent_samples = 0;
 610         devc->acq_aborted = FALSE;
 611         devc->empty_transfer_count = 0;
 612
 613         if ((trigger = sr_session_trigger_get(sdi->session))) {
 614                 int pre_trigger_samples = 0;
 615                 if (devc->limit_samples > 0)
 616                         pre_trigger_samples = devc->capture_ratio * devc->limit_samples/100;
 617                 devc->stl = soft_trigger_logic_new(sdi, trigger, pre_trigger_samples);
 618                 if (!devc->stl)
 619                         return SR_ERR_MALLOC;
 620                 devc->trigger_fired = FALSE;
 621         } else
 622                 devc->trigger_fired = TRUE;
 623
 624         num_transfers = get_number_of_transfers(devc);
 625
 626         size = get_buffer_size(devc);
 627         devc->submitted_transfers = 0;
 628
 629         devc->transfers = g_try_malloc0(sizeof(*devc->transfers) * num_transfers);
 630         if (!devc->transfers) {
 631                 sr_err("USB transfers malloc failed.");
 632                 return SR_ERR_MALLOC;
 633         }
 634
 635         timeout = get_timeout(devc);
 636         devc->num_transfers = num_transfers;
 637         for (i = 0; i < num_transfers; i++) {
 638                 if (!(buf = g_try_malloc(size))) {
 639                         sr_err("USB transfer buffer malloc failed.");
 640                         return SR_ERR_MALLOC;
 641                 }
 642                 transfer = libusb_alloc_transfer(0);
 643                 libusb_fill_bulk_transfer(transfer, usb->devhdl,
 644                                 2 | LIBUSB_ENDPOINT_IN, buf, size,
 645                                 receive_transfer, (void *)sdi, timeout);
 646                 sr_info("submitting transfer: %d", i);
 647                 if ((ret = libusb_submit_transfer(transfer)) != 0) {
 648                         sr_err("Failed to submit transfer: %s.",
 649                                libusb_error_name(ret));
 650                         libusb_free_transfer(transfer);
 651                         g_free(buf);
 652                         fx2lafw_abort_acquisition(devc);
 653                         return SR_ERR;
 654                 }
 655                 devc->transfers[i] = transfer;
 656                 devc->submitted_transfers++;
 657         }
 658
 659         /*
 660          * If this device has analog channels and at least one of them is
 661          * enabled, use mso_send_data_proc() to properly handle the analog
 662          * data. Otherwise use la_send_data_proc().
 663          */
 664         if (g_slist_length(devc->enabled_analog_channels) > 0)
 665                 devc->send_data_proc = mso_send_data_proc;
 666         else
 667                 devc->send_data_proc = la_send_data_proc;
 668
 669         std_session_send_df_header(sdi);
 670
 671         return SR_OK;
 672 }
 673
 674 SR_PRIV int fx2lafw_start_acquisition(const struct sr_dev_inst *sdi)
 675 {
 676         struct sr_dev_driver *di;
 677         struct drv_context *drvc;
 678         struct dev_context *devc;
 679         int timeout, ret;
 680         size_t size;
 681
 682         di = sdi->driver;
 683         drvc = di->context;
 684         devc = sdi->priv;
 685
 686         devc->ctx = drvc->sr_ctx;
 687         devc->sent_samples = 0;
 688         devc->empty_transfer_count = 0;
 689         devc->acq_aborted = FALSE;
 690
 691         if (configure_channels(sdi) != SR_OK) {
 692                 sr_err("Failed to configure channels.");
 693                 return SR_ERR;
 694         }
 695
 696         timeout = get_timeout(devc);
 697         usb_source_add(sdi->session, devc->ctx, timeout, receive_data, drvc);
 698
 699         size = get_buffer_size(devc);
 700         /* Prepare for analog sampling. */
 701         if (g_slist_length(devc->enabled_analog_channels) > 0) {
 702                 /* We need a buffer half the size of a transfer. */
 703                 devc->logic_buffer = g_try_malloc(size / 2);
 704                 devc->analog_buffer = g_try_malloc(
 705                         sizeof(float) * size / 2);
 706         }
 707         start_transfers(sdi);
 708         if ((ret = command_start_acquisition(sdi)) != SR_OK) {
 709                 fx2lafw_abort_acquisition(devc);
 710                 return ret;
 711         }
 712
 713         return SR_OK;
 714 }