hardware/saleae-logic/saleae-logic.c

   1 /*
   2  * This file is part of the sigrok project.
   3  *
   4  * Copyright (C) 2010 Bert Vermeulen <bert@biot.com>
   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 <stdio.h>
  21 #include <stdlib.h>
  22 #include <sys/time.h>
  23 #include <inttypes.h>
  24 #include <glib.h>
  25 #include <libusb.h>
  26 #include "config.h"
  27 #include "sigrok.h"
  28
  29 #define USB_VENDOR                      0x0925
  30 #define USB_PRODUCT                     0x3881
  31 #define USB_VENDOR_NAME                 "Saleae"
  32 #define USB_MODEL_NAME                  "Logic"
  33 #define USB_MODEL_VERSION               ""
  34
  35 #define USB_INTERFACE                   0
  36 #define USB_CONFIGURATION               1
  37 #define NUM_PROBES                      8
  38 #define NUM_TRIGGER_STAGES              4
  39 #define TRIGGER_TYPES                   "01"
  40 #define FIRMWARE                        FIRMWARE_DIR "/saleae-logic.firmware"
  41
  42 /* delay in ms */
  43 #define FIRMWARE_RENUM_DELAY            2000
  44 #define NUM_SIMUL_TRANSFERS             10
  45 #define MAX_EMPTY_TRANSFERS             (NUM_SIMUL_TRANSFERS * 2)
  46
  47 /* software trigger implementation: positive values indicate trigger stage */
  48 #define TRIGGER_FIRED                   -1
  49
  50 /* There is only one model Saleae Logic, and this is what it supports: */
  51 static int capabilities[] = {
  52         HWCAP_LOGIC_ANALYZER,
  53         HWCAP_SAMPLERATE,
  54
  55         /* These are really implemented in the driver, not the hardware. */
  56         HWCAP_LIMIT_SAMPLES,
  57         0,
  58 };
  59
  60 /* List of struct sigrok_device_instance, maintained by opendev()/closedev(). */
  61 static GSList *device_instances = NULL;
  62
  63 /*
  64  * Since we can't keep track of a Saleae Logic device after upgrading the
  65  * firmware -- it re-enumerates into a different device address after the
  66  * upgrade -- this is like a global lock. No device will open until a proper
  67  * delay after the last device was upgraded.
  68  */
  69 GTimeVal firmware_updated = { 0 };
  70
  71 static libusb_context *usb_context = NULL;
  72
  73 static uint64_t supported_samplerates[] = {
  74         KHZ(200),
  75         KHZ(250),
  76         KHZ(500),
  77         MHZ(1),
  78         MHZ(2),
  79         MHZ(4),
  80         MHZ(8),
  81         MHZ(12),
  82         MHZ(16),
  83         MHZ(24),
  84         0,
  85 };
  86
  87 static struct samplerates samplerates = {
  88         KHZ(200),
  89         MHZ(24),
  90         0,
  91         supported_samplerates,
  92 };
  93
  94 /* TODO: All of these should go in a device-specific struct. */
  95 static uint64_t cur_samplerate = 0;
  96 static uint64_t limit_samples = 0;
  97 static uint8_t probe_mask = 0;
  98 static uint8_t trigger_mask[NUM_TRIGGER_STAGES] = { 0 };
  99 static uint8_t trigger_value[NUM_TRIGGER_STAGES] = { 0 };
 100 static uint8_t trigger_buffer[NUM_TRIGGER_STAGES] = { 0 };
 101 int trigger_stage = TRIGGER_FIRED;
 102
 103 static int hw_set_configuration(int device_index, int capability, void *value);
 104
 105 /* returns 1 if the device's configuration profile match the Logic firmware's
 106  * configuration, 0 otherwise
 107  */
 108 int check_conf_profile(libusb_device *dev)
 109 {
 110         struct libusb_device_descriptor des;
 111         struct libusb_config_descriptor *conf_dsc = NULL;
 112         const struct libusb_interface_descriptor *intf_dsc;
 113         int ret = -1;
 114
 115         while (ret == -1) {
 116                 /* Assume it's not a Saleae Logic unless proven wrong. */
 117                 ret = 0;
 118
 119                 if (libusb_get_device_descriptor(dev, &des) != 0)
 120                         break;
 121
 122                 if (des.bNumConfigurations != 1)
 123                         /* Need exactly 1 configuration. */
 124                         break;
 125
 126                 if (libusb_get_config_descriptor(dev, 0, &conf_dsc) != 0)
 127                         break;
 128
 129                 if (conf_dsc->bNumInterfaces != 1)
 130                         /* Need exactly 1 interface. */
 131                         break;
 132
 133                 if (conf_dsc->interface[0].num_altsetting != 1)
 134                         /* Need just one alternate setting. */
 135                         break;
 136
 137                 intf_dsc = &(conf_dsc->interface[0].altsetting[0]);
 138                 if (intf_dsc->bNumEndpoints != 2)
 139                         /* Need 2 endpoints. */
 140                         break;
 141
 142                 if ((intf_dsc->endpoint[0].bEndpointAddress & 0x8f) !=
 143                     (1 | LIBUSB_ENDPOINT_OUT))
 144                         /* First endpoint should be 1 (outbound). */
 145                         break;
 146
 147                 if ((intf_dsc->endpoint[1].bEndpointAddress & 0x8f) !=
 148                     (2 | LIBUSB_ENDPOINT_IN))
 149                         /* First endpoint should be 2 (inbound). */
 150                         break;
 151
 152                 /* If we made it here, it must be a Saleae Logic. */
 153                 ret = 1;
 154         }
 155
 156         if (conf_dsc)
 157                 libusb_free_config_descriptor(conf_dsc);
 158
 159         return ret;
 160 }
 161
 162 static int opendev2(int device_index, struct sigrok_device_instance **sdi,
 163                     libusb_device *dev, struct libusb_device_descriptor *des,
 164                     int *skip)
 165 {
 166         int err;
 167
 168         if ((err = libusb_get_device_descriptor(dev, des))) {
 169                 g_warning("failed to get device descriptor: %d", err);
 170                 return -1;
 171         }
 172
 173         if (des->idVendor != USB_VENDOR || des->idProduct != USB_PRODUCT)
 174                 return 0;
 175
 176         if (*skip != device_index) {
 177                 /* Skip devices of this type that aren't the one we want. */
 178                 *skip += 1;
 179                 return 0;
 180         }
 181
 182         /*
 183          * Should check the bus here, since we know that already. But what are
 184          * we going to do if it doesn't match after the right number of skips?
 185          */
 186         if (!(err = libusb_open(dev, &((*sdi)->usb->devhdl)))) {
 187                 (*sdi)->usb->address = libusb_get_device_address(dev);
 188                 (*sdi)->status = ST_ACTIVE;
 189                 g_message("opened device %d on %d.%d interface %d",
 190                           (*sdi)->index, (*sdi)->usb->bus,
 191                           (*sdi)->usb->address, USB_INTERFACE);
 192         } else {
 193                 g_warning("failed to open device: %d", err);
 194                 *sdi = NULL;
 195         }
 196
 197         return 0;
 198 }
 199
 200 static int opendev3(int device_index, struct sigrok_device_instance **sdi,
 201                     libusb_device *dev, struct libusb_device_descriptor *des)
 202 {
 203         int err;
 204
 205         if ((err = libusb_get_device_descriptor(dev, des))) {
 206                 g_warning("failed to get device descriptor: %d", err);
 207                 return -1;
 208         }
 209
 210         if (des->idVendor != USB_VENDOR || des->idProduct != USB_PRODUCT)
 211                 return 0;
 212
 213         if (libusb_get_bus_number(dev) == (*sdi)->usb->bus
 214             && libusb_get_device_address(dev) == (*sdi)->usb->address) {
 215                 /* Found it. */
 216                 if (!(err = libusb_open(dev, &((*sdi)->usb->devhdl)))) {
 217                         (*sdi)->status = ST_ACTIVE;
 218                         g_message("opened device %d on %d.%d interface %d",
 219                                   (*sdi)->index, (*sdi)->usb->bus,
 220                                   (*sdi)->usb->address, USB_INTERFACE);
 221                 } else {
 222                         g_warning("failed to open device: %d", err);
 223                         *sdi = NULL;
 224                 }
 225         }
 226
 227         return 0;
 228 }
 229
 230 struct sigrok_device_instance *sl_open_device(int device_index)
 231 {
 232         struct sigrok_device_instance *sdi;
 233         libusb_device **devlist;
 234         struct libusb_device_descriptor des;
 235         int err, skip, i;
 236
 237         if (!(sdi = get_sigrok_device_instance(device_instances, device_index)))
 238                 return NULL;
 239
 240         libusb_get_device_list(usb_context, &devlist);
 241         if (sdi->status == ST_INITIALIZING) {
 242                 /*
 243                  * This device was renumerating last time we touched it.
 244                  * opendev() guarantees we've waited long enough for it to
 245                  * have booted properly, so now we need to find it on
 246                  * the bus and record its new address.
 247                  */
 248                 skip = 0;
 249                 for (i = 0; devlist[i]; i++) {
 250                         /* TODO: Error handling. */
 251                         err = opendev2(device_index, &sdi, devlist[i], &des,
 252                                        &skip);
 253                 }
 254         } else if (sdi->status == ST_INACTIVE) {
 255                 /*
 256                  * This device is fully enumerated, so we need to find this
 257                  * device by vendor, product, bus and address.
 258                  */
 259                 libusb_get_device_list(usb_context, &devlist);
 260                 for (i = 0; devlist[i]; i++) {
 261                         /* TODO: Error handling. */
 262                         err = opendev3(device_index, &sdi, devlist[i], &des);
 263                 }
 264         } else {
 265                 /* Status must be ST_ACTIVE, i.e. already in use... */
 266                 sdi = NULL;
 267         }
 268         libusb_free_device_list(devlist, 1);
 269
 270         if (sdi && sdi->status != ST_ACTIVE)
 271                 sdi = NULL;
 272
 273         return sdi;
 274 }
 275
 276 int upload_firmware(libusb_device *dev)
 277 {
 278         int ret;
 279
 280         ret = ezusb_upload_firmware(dev, USB_CONFIGURATION, FIRMWARE);
 281         if (ret != 0)
 282                 return 1;
 283
 284         /* Remember when the last firmware update was done. */
 285         g_get_current_time(&firmware_updated);
 286
 287         return 0;
 288 }
 289
 290 static void close_device(struct sigrok_device_instance *sdi)
 291 {
 292         if (sdi->usb->devhdl == NULL)
 293                 return;
 294
 295         g_message("closing device %d on %d.%d interface %d", sdi->index,
 296                   sdi->usb->bus, sdi->usb->address, USB_INTERFACE);
 297         libusb_release_interface(sdi->usb->devhdl, USB_INTERFACE);
 298         libusb_close(sdi->usb->devhdl);
 299         sdi->usb->devhdl = NULL;
 300         sdi->status = ST_INACTIVE;
 301 }
 302
 303 static int configure_probes(GSList * probes)
 304 {
 305         struct probe *probe;
 306         GSList *l;
 307         int probe_bit, stage, i;
 308         char *tc;
 309
 310         probe_mask = 0;
 311         for (i = 0; i < NUM_TRIGGER_STAGES; i++) {
 312                 trigger_mask[i] = 0;
 313                 trigger_value[i] = 0;
 314         }
 315
 316         stage = -1;
 317         for (l = probes; l; l = l->next) {
 318                 probe = (struct probe *)l->data;
 319                 if (probe->enabled == FALSE)
 320                         continue;
 321                 probe_bit = 1 << (probe->index - 1);
 322                 probe_mask |= probe_bit;
 323                 if (probe->trigger) {
 324                         stage = 0;
 325                         for (tc = probe->trigger; *tc; tc++) {
 326                                 trigger_mask[stage] |= probe_bit;
 327                                 if (*tc == '1')
 328                                         trigger_value[stage] |= probe_bit;
 329                                 stage++;
 330                                 if (stage > NUM_TRIGGER_STAGES)
 331                                         return SIGROK_ERR;
 332                         }
 333                 }
 334         }
 335
 336         if (stage == -1)
 337                 /*
 338                  * We didn't configure any triggers, make sure acquisition
 339                  * doesn't wait for any.
 340                  */
 341                 trigger_stage = TRIGGER_FIRED;
 342         else
 343                 trigger_stage = 0;
 344
 345         return SIGROK_OK;
 346 }
 347
 348 /*
 349  * API callbacks
 350  */
 351
 352 static int hw_init(char *deviceinfo)
 353 {
 354         struct sigrok_device_instance *sdi;
 355         struct libusb_device_descriptor des;
 356         libusb_device **devlist;
 357         int err, devcnt, i;
 358
 359         if (libusb_init(&usb_context) != 0) {
 360                 g_warning("Failed to initialize USB.");
 361                 return 0;
 362         }
 363         libusb_set_debug(usb_context, 3);
 364
 365         /* Find all Saleae Logic devices and upload firmware to all of them. */
 366         devcnt = 0;
 367         libusb_get_device_list(usb_context, &devlist);
 368         for (i = 0; devlist[i]; i++) {
 369                 err = libusb_get_device_descriptor(devlist[i], &des);
 370                 if (err != 0) {
 371                         g_warning("failed to get device descriptor: %d", err);
 372                         continue;
 373                 }
 374
 375                 if (des.idVendor != USB_VENDOR || des.idProduct != USB_PRODUCT)
 376                         continue; /* Not a Saleae Logic... */
 377
 378                 sdi = sigrok_device_instance_new(devcnt, ST_INITIALIZING,
 379                         USB_VENDOR_NAME, USB_MODEL_NAME, USB_MODEL_VERSION);
 380                 if (!sdi)
 381                         return 0;
 382                 device_instances = g_slist_append(device_instances, sdi);
 383
 384                 if (check_conf_profile(devlist[i]) == 0) {
 385                         /*
 386                          * Continue on the off chance that the device is in a
 387                          * working state. TODO: Could maybe try a USB reset,
 388                          * or uploading the firmware again.
 389                          */
 390                         if (upload_firmware(devlist[i]) > 0)
 391                                 g_warning("firmware upload failed for device %d", devcnt);
 392
 393                         sdi->usb = usb_device_instance_new
 394                           (libusb_get_bus_number(devlist[i]), 0, NULL);
 395                 } else {
 396                         /* Already has the firmware, so fix the new address. */
 397                         sdi->usb = usb_device_instance_new
 398                             (libusb_get_bus_number(devlist[i]),
 399                              libusb_get_device_address(devlist[i]),
 400                              NULL);
 401                 }
 402                 devcnt++;
 403         }
 404         libusb_free_device_list(devlist, 1);
 405
 406         return devcnt;
 407 }
 408
 409 static int hw_opendev(int device_index)
 410 {
 411         GTimeVal cur_time;
 412         struct sigrok_device_instance *sdi;
 413         int timediff, err;
 414         unsigned int cur, upd;
 415
 416         if (firmware_updated.tv_sec > 0) {
 417                 /* Firmware was recently uploaded. */
 418                 g_get_current_time(&cur_time);
 419                 cur = cur_time.tv_sec * 1000 + cur_time.tv_usec / 1000;
 420                 upd = firmware_updated.tv_sec * 1000 +
 421                       firmware_updated.tv_usec / 1000;
 422                 timediff = cur - upd;
 423                 if (timediff < FIRMWARE_RENUM_DELAY) {
 424                         timediff = FIRMWARE_RENUM_DELAY - timediff;
 425                         g_message("waiting %d ms for device to reset",
 426                                   timediff);
 427                         g_usleep(timediff * 1000);
 428                         firmware_updated.tv_sec = 0;
 429                 }
 430         }
 431
 432         if (!(sdi = sl_open_device(device_index))) {
 433                 g_warning("unable to open device");
 434                 return SIGROK_ERR;
 435         }
 436
 437         err = libusb_claim_interface(sdi->usb->devhdl, USB_INTERFACE);
 438         if (err != 0) {
 439                 g_warning("Unable to claim interface: %d", err);
 440                 return SIGROK_ERR;
 441         }
 442
 443         if (cur_samplerate == 0) {
 444                 /* Samplerate hasn't been set; default to the slowest one. */
 445                 if (hw_set_configuration(device_index, HWCAP_SAMPLERATE,
 446                      &supported_samplerates[0]) == SIGROK_ERR)
 447                         return SIGROK_ERR;
 448         }
 449
 450         return SIGROK_OK;
 451 }
 452
 453 static void hw_closedev(int device_index)
 454 {
 455         struct sigrok_device_instance *sdi;
 456
 457         if ((sdi = get_sigrok_device_instance(device_instances, device_index)))
 458                 close_device(sdi);
 459 }
 460
 461 static void hw_cleanup(void)
 462 {
 463         GSList *l;
 464
 465         /* Properly close all devices... */
 466         for (l = device_instances; l; l = l->next)
 467                 close_device((struct sigrok_device_instance *)l->data);
 468
 469         /* ...and free all their memory. */
 470         for (l = device_instances; l; l = l->next)
 471                 g_free(l->data);
 472         g_slist_free(device_instances);
 473         device_instances = NULL;
 474
 475         if (usb_context)
 476                 libusb_exit(usb_context);
 477         usb_context = NULL;
 478 }
 479
 480 static void *hw_get_device_info(int device_index, int device_info_id)
 481 {
 482         struct sigrok_device_instance *sdi;
 483         void *info = NULL;
 484
 485         if (!(sdi = get_sigrok_device_instance(device_instances, device_index)))
 486                 return NULL;
 487
 488         switch (device_info_id) {
 489         case DI_INSTANCE:
 490                 info = sdi;
 491                 break;
 492         case DI_NUM_PROBES:
 493                 info = GINT_TO_POINTER(NUM_PROBES);
 494                 break;
 495         case DI_SAMPLERATES:
 496                 info = &samplerates;
 497                 break;
 498         case DI_TRIGGER_TYPES:
 499                 info = TRIGGER_TYPES;
 500                 break;
 501         case DI_CUR_SAMPLERATE:
 502                 info = &cur_samplerate;
 503                 break;
 504         }
 505
 506         return info;
 507 }
 508
 509 static int hw_get_status(int device_index)
 510 {
 511         struct sigrok_device_instance *sdi;
 512
 513         sdi = get_sigrok_device_instance(device_instances, device_index);
 514         if (sdi)
 515                 return sdi->status;
 516         else
 517                 return ST_NOT_FOUND;
 518 }
 519
 520 static int *hw_get_capabilities(void)
 521 {
 522         return capabilities;
 523 }
 524
 525 static int set_configuration_samplerate(struct sigrok_device_instance *sdi,
 526                                         uint64_t samplerate)
 527 {
 528         uint8_t divider;
 529         int ret, result, i;
 530         unsigned char buf[2];
 531
 532         for (i = 0; supported_samplerates[i]; i++) {
 533                 if (supported_samplerates[i] == samplerate)
 534                         break;
 535         }
 536         if (supported_samplerates[i] == 0)
 537                 return SIGROK_ERR_SAMPLERATE;
 538
 539         divider = (uint8_t) (48 / (float)(samplerate / 1000000)) - 1;
 540
 541         g_message("setting samplerate to %" PRIu64 " Hz (divider %d)",
 542                   samplerate, divider);
 543         buf[0] = 0x01;
 544         buf[1] = divider;
 545         ret = libusb_bulk_transfer(sdi->usb->devhdl, 1 | LIBUSB_ENDPOINT_OUT,
 546                                    buf, 2, &result, 500);
 547         if (ret != 0) {
 548                 g_warning("failed to set samplerate: %d", ret);
 549                 return SIGROK_ERR;
 550         }
 551         cur_samplerate = samplerate;
 552
 553         return SIGROK_OK;
 554 }
 555
 556 static int hw_set_configuration(int device_index, int capability, void *value)
 557 {
 558         struct sigrok_device_instance *sdi;
 559         int ret;
 560         uint64_t *tmp_u64;
 561
 562         if (!(sdi = get_sigrok_device_instance(device_instances, device_index)))
 563                 return SIGROK_ERR;
 564
 565         if (capability == HWCAP_SAMPLERATE) {
 566                 tmp_u64 = value;
 567                 ret = set_configuration_samplerate(sdi, *tmp_u64);
 568         } else if (capability == HWCAP_PROBECONFIG) {
 569                 ret = configure_probes((GSList *) value);
 570         } else if (capability == HWCAP_LIMIT_SAMPLES) {
 571                 limit_samples = strtoull(value, NULL, 10);
 572                 ret = SIGROK_OK;
 573         } else {
 574                 ret = SIGROK_ERR;
 575         }
 576
 577         return ret;
 578 }
 579
 580 static int receive_data(int fd, int revents, void *user_data)
 581 {
 582         struct timeval tv;
 583
 584         tv.tv_sec = tv.tv_usec = 0;
 585         libusb_handle_events_timeout(usb_context, &tv);
 586
 587         return TRUE;
 588 }
 589
 590 static void trigger_helper(int i, unsigned char *cur_buf, int cur_buflen,
 591                            struct datafeed_packet *packet, void *user_data,
 592                            int *trigger_offset)
 593 {
 594         if ((cur_buf[i] & trigger_mask[trigger_stage])
 595             == trigger_value[trigger_stage]) {
 596                 /* Match on this trigger stage. */
 597                 trigger_buffer[trigger_stage] = cur_buf[i];
 598                 trigger_stage++;
 599                 if (trigger_stage == NUM_TRIGGER_STAGES
 600                     || trigger_mask[trigger_stage] == 0) {
 601                         /* Match on all trigger stages, we're done. */
 602                         *trigger_offset = i + 1;
 603
 604                         /*
 605                          * TODO: Send pre-trigger buffer to session bus.
 606                          * Tell the frontend we hit the trigger here.
 607                          */
 608                         packet->type = DF_TRIGGER;
 609                         packet->length = 0;
 610                         session_bus(user_data, packet);
 611
 612                         /*
 613                          * Send the samples that triggered it, since we're
 614                          * skipping past them.
 615                          */
 616                         packet->type = DF_LOGIC8;
 617                         packet->length = trigger_stage;
 618                         packet->payload = trigger_buffer;
 619                         session_bus(user_data, packet);
 620                         // break; // FIXME???
 621
 622                         trigger_stage = TRIGGER_FIRED;
 623                 }
 624                 return;
 625         }
 626
 627         /*
 628          * We had a match before, but not in the next sample. However, we may
 629          * have a match on this stage in the next bit -- trigger on 0001 will
 630          * fail on seeing 00001, so we need to go back to stage 0 -- but at
 631          * the next sample from the one that matched originally, which the
 632          * counter increment at the end of the loop takes care of.
 633          */
 634         if (trigger_stage > 0) {
 635                 i -= trigger_stage;
 636                 if (i < -1)
 637                         i = -1; /* Oops, went back past this buffer. */
 638                 /* Reset trigger stage. */
 639                 trigger_stage = 0;
 640         }
 641 }
 642
 643 void receive_transfer(struct libusb_transfer *transfer)
 644 {
 645         static int num_samples = 0;
 646         static int empty_transfer_count = 0;
 647         struct datafeed_packet packet;
 648         void *user_data;
 649         int cur_buflen, trigger_offset, i;
 650         unsigned char *cur_buf, *new_buf;
 651
 652         /* hw_stop_acquisition() is telling us to stop. */
 653         if (transfer == NULL)
 654                 num_samples = -1;
 655
 656         /*
 657          * If acquisition has already ended, just free any queued up
 658          * transfer that come in.
 659          */
 660         if (num_samples == -1) {
 661                 libusb_free_transfer(transfer);
 662                 return;
 663         }
 664
 665         g_message("receive_transfer(): status %d received %d bytes",
 666                   transfer->status, transfer->actual_length);
 667
 668         /* Save incoming transfer before reusing the transfer struct. */
 669         cur_buf = transfer->buffer;
 670         cur_buflen = transfer->actual_length;
 671         user_data = transfer->user_data;
 672
 673         /* Fire off a new request. */
 674         new_buf = g_malloc(4096);
 675         transfer->buffer = new_buf;
 676         transfer->length = 4096;
 677         if (libusb_submit_transfer(transfer) != 0) {
 678                 /* TODO: Stop session? */
 679                 g_warning("eek");
 680         }
 681
 682         if (cur_buflen == 0) {
 683                 empty_transfer_count++;
 684                 if (empty_transfer_count > MAX_EMPTY_TRANSFERS) {
 685                         /*
 686                          * The FX2 gave up. End the acquisition, the frontend
 687                          * will work out that the samplecount is short.
 688                          */
 689                         packet.type = DF_END;
 690                         session_bus(user_data, &packet);
 691                         num_samples = -1;
 692                 }
 693                 return;
 694         } else {
 695                 empty_transfer_count = 0;
 696         }
 697
 698         trigger_offset = 0;
 699         if (trigger_stage >= 0) {
 700                 for (i = 0; i < cur_buflen; i++) {
 701                         trigger_helper(i, cur_buf, cur_buflen, &packet,
 702                                        user_data, &trigger_offset);
 703                 }
 704         }
 705
 706         if (trigger_stage == TRIGGER_FIRED) {
 707                 /* Send the incoming transfer to the session bus. */
 708                 packet.type = DF_LOGIC8;
 709                 packet.length = cur_buflen - trigger_offset;
 710                 packet.payload = cur_buf + trigger_offset;
 711                 session_bus(user_data, &packet);
 712                 g_free(cur_buf);
 713
 714                 num_samples += cur_buflen;
 715                 if (num_samples > limit_samples) {
 716                         /* End the acquisition. */
 717                         packet.type = DF_END;
 718                         session_bus(user_data, &packet);
 719                         num_samples = -1;
 720                 }
 721         } else {
 722                 /*
 723                  * TODO: Buffer pre-trigger data in capture
 724                  * ratio-sized buffer.
 725                  */
 726         }
 727 }
 728
 729 static int hw_start_acquisition(int device_index, gpointer session_device_id)
 730 {
 731         struct sigrok_device_instance *sdi;
 732         struct datafeed_packet *packet;
 733         struct datafeed_header *header;
 734         struct libusb_transfer *transfer;
 735         const struct libusb_pollfd **lupfd;
 736         int size, i;
 737         unsigned char *buf;
 738
 739         if (!(sdi = get_sigrok_device_instance(device_instances, device_index)))
 740                 return SIGROK_ERR;
 741
 742         packet = g_malloc(sizeof(struct datafeed_packet));
 743         header = g_malloc(sizeof(struct datafeed_header));
 744         if (!packet || !header)
 745                 return SIGROK_ERR;
 746
 747         /* Start with 2K transfer, subsequently increased to 4K. */
 748         size = 2048;
 749         for (i = 0; i < NUM_SIMUL_TRANSFERS; i++) {
 750                 buf = g_malloc(size);
 751                 transfer = libusb_alloc_transfer(0);
 752                 libusb_fill_bulk_transfer(transfer, sdi->usb->devhdl,
 753                                 2 | LIBUSB_ENDPOINT_IN, buf, size,
 754                                 receive_transfer, session_device_id, 40);
 755                 if (libusb_submit_transfer(transfer) != 0) {
 756                         /* TODO: Free them all. */
 757                         libusb_free_transfer(transfer);
 758                         g_free(buf);
 759                         return SIGROK_ERR;
 760                 }
 761                 size = 4096;
 762         }
 763
 764         lupfd = libusb_get_pollfds(usb_context);
 765         for (i = 0; lupfd[i]; i++)
 766                 source_add(lupfd[i]->fd, lupfd[i]->events, -1, receive_data,
 767                            NULL);
 768         free(lupfd);
 769
 770         packet->type = DF_HEADER;
 771         packet->length = sizeof(struct datafeed_header);
 772         packet->payload = (unsigned char *)header;
 773         header->feed_version = 1;
 774         gettimeofday(&header->starttime, NULL);
 775         header->samplerate = cur_samplerate;
 776         header->protocol_id = PROTO_RAW;
 777         header->num_probes = NUM_PROBES;
 778         session_bus(session_device_id, packet);
 779         g_free(header);
 780         g_free(packet);
 781
 782         return SIGROK_OK;
 783 }
 784
 785 /* This stops acquisition on ALL devices, ignoring device_index. */
 786 static void hw_stop_acquisition(int device_index, gpointer session_device_id)
 787 {
 788         struct datafeed_packet packet;
 789
 790         packet.type = DF_END;
 791         session_bus(session_device_id, &packet);
 792
 793         receive_transfer(NULL);
 794
 795         /* TODO: Need to cancel and free any queued up transfers. */
 796 }
 797
 798 struct device_plugin saleae_logic_plugin_info = {
 799         "saleae-logic",
 800         1,
 801         hw_init,
 802         hw_cleanup,
 803
 804         hw_opendev,
 805         hw_closedev,
 806         hw_get_device_info,
 807         hw_get_status,
 808         hw_get_capabilities,
 809         hw_set_configuration,
 810         hw_start_acquisition,
 811         hw_stop_acquisition,
 812 };