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 "config.h"
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <sys/time.h>
  24 #include <inttypes.h>
  25 #include <glib.h>
  26 #include <libusb.h>
  27 #include <sigrok.h>
  28 #include <sigrok-internal.h>
  29
  30 #define USB_INTERFACE          0
  31 #define USB_CONFIGURATION      1
  32 #define NUM_TRIGGER_STAGES     4
  33 #define TRIGGER_TYPES          "01"
  34 #define FIRMWARE               FIRMWARE_DIR "/saleae-logic.fw"
  35 #define GTV_TO_MSEC(gtv)       (gtv.tv_sec * 1000 + gtv.tv_usec / 1000)
  36
  37 /* delay in ms */
  38 #define MAX_RENUM_DELAY        3000
  39 #define NUM_SIMUL_TRANSFERS    10
  40 #define MAX_EMPTY_TRANSFERS    (NUM_SIMUL_TRANSFERS * 2)
  41
  42 /* Software trigger implementation: positive values indicate trigger stage. */
  43 #define TRIGGER_FIRED          -1
  44
  45 struct fx2_device {
  46         /* VID/PID when first found */
  47         uint16_t orig_vid;
  48         uint16_t orig_pid;
  49         /* VID/PID after firmware upload */
  50         uint16_t fw_vid;
  51         uint16_t fw_pid;
  52         char *vendor;
  53         char *model;
  54         char *model_version;
  55         int num_probes;
  56 };
  57
  58 static struct fx2_device supported_fx2[] = {
  59         /* Saleae Logic */
  60         { 0x0925, 0x3881, 0x0925, 0x3881, "Saleae", "Logic", NULL, 8 },
  61         /* default Cypress FX2 without EEPROM */
  62         { 0x04b4, 0x8613, 0x0925, 0x3881, "Cypress", "FX2", NULL, 16 },
  63         { 0, 0, 0, 0, NULL, NULL, NULL, 0 }
  64 };
  65
  66 /* There is only one model Saleae Logic, and this is what it supports: */
  67 static int capabilities[] = {
  68         SR_HWCAP_LOGIC_ANALYZER,
  69         SR_HWCAP_SAMPLERATE,
  70
  71         /* These are really implemented in the driver, not the hardware. */
  72         SR_HWCAP_LIMIT_SAMPLES,
  73         SR_HWCAP_CONTINUOUS,
  74         0,
  75 };
  76
  77 /* List of struct sr_device_instance, maintained by opendev()/closedev(). */
  78 static GSList *device_instances = NULL;
  79
  80 /*
  81  * Since we can't keep track of a Saleae Logic device after upgrading the
  82  * firmware -- it re-enumerates into a different device address after the
  83  * upgrade -- this is like a global lock. No device will open until a proper
  84  * delay after the last device was upgraded.
  85  */
  86 static GTimeVal fw_updated = { 0, 0 };
  87
  88 static libusb_context *usb_context = NULL;
  89
  90 static uint64_t supported_samplerates[] = {
  91         SR_KHZ(200),
  92         SR_KHZ(250),
  93         SR_KHZ(500),
  94         SR_MHZ(1),
  95         SR_MHZ(2),
  96         SR_MHZ(4),
  97         SR_MHZ(8),
  98         SR_MHZ(12),
  99         SR_MHZ(16),
 100         SR_MHZ(24),
 101         0,
 102 };
 103
 104 static struct sr_samplerates samplerates = {
 105         SR_KHZ(200),
 106         SR_MHZ(24),
 107         SR_HZ(0),
 108         supported_samplerates,
 109 };
 110
 111 /* TODO: All of these should go in a device-specific struct. */
 112 static uint64_t cur_samplerate = 0;
 113 static uint64_t limit_samples = 0;
 114 static uint8_t probe_mask = 0;
 115 static uint8_t trigger_mask[NUM_TRIGGER_STAGES] = { 0 };
 116 static uint8_t trigger_value[NUM_TRIGGER_STAGES] = { 0 };
 117 static uint8_t trigger_buffer[NUM_TRIGGER_STAGES] = { 0 };
 118 static struct fx2_device *fx2 = NULL;
 119 static int trigger_stage = TRIGGER_FIRED;
 120
 121 static int hw_set_configuration(int device_index, int capability, void *value);
 122 static void hw_stop_acquisition(int device_index, gpointer session_device_id);
 123
 124 /**
 125  * Check the USB configuration to determine if this is a Saleae Logic.
 126  *
 127  * @return 1 if the device's configuration profile match the Logic firmware's
 128  *         configuration, 0 otherwise.
 129  */
 130 static int check_conf_profile(libusb_device *dev)
 131 {
 132         struct libusb_device_descriptor des;
 133         struct libusb_config_descriptor *conf_dsc = NULL;
 134         const struct libusb_interface_descriptor *intf_dsc;
 135         int ret = -1;
 136
 137         while (ret == -1) {
 138                 /* Assume it's not a Saleae Logic unless proven wrong. */
 139                 ret = 0;
 140
 141                 if (libusb_get_device_descriptor(dev, &des) != 0)
 142                         break;
 143
 144                 if (des.bNumConfigurations != 1)
 145                         /* Need exactly 1 configuration. */
 146                         break;
 147
 148                 if (libusb_get_config_descriptor(dev, 0, &conf_dsc) != 0)
 149                         break;
 150
 151                 if (conf_dsc->bNumInterfaces != 1)
 152                         /* Need exactly 1 interface. */
 153                         break;
 154
 155                 if (conf_dsc->interface[0].num_altsetting != 1)
 156                         /* Need just one alternate setting. */
 157                         break;
 158
 159                 intf_dsc = &(conf_dsc->interface[0].altsetting[0]);
 160                 if (intf_dsc->bNumEndpoints != 2)
 161                         /* Need 2 endpoints. */
 162                         break;
 163
 164                 if ((intf_dsc->endpoint[0].bEndpointAddress & 0x8f) !=
 165                     (1 | LIBUSB_ENDPOINT_OUT))
 166                         /* First endpoint should be 1 (outbound). */
 167                         break;
 168
 169                 if ((intf_dsc->endpoint[1].bEndpointAddress & 0x8f) !=
 170                     (2 | LIBUSB_ENDPOINT_IN))
 171                         /* First endpoint should be 2 (inbound). */
 172                         break;
 173
 174                 /* If we made it here, it must be a Saleae Logic. */
 175                 ret = 1;
 176         }
 177
 178         if (conf_dsc)
 179                 libusb_free_config_descriptor(conf_dsc);
 180
 181         return ret;
 182 }
 183
 184 static struct sr_device_instance *sl_open_device(int device_index)
 185 {
 186         libusb_device **devlist;
 187         struct libusb_device_descriptor des;
 188         struct sr_device_instance *sdi;
 189         int err, skip, i;
 190
 191         if (!(sdi = sr_get_device_instance(device_instances, device_index)))
 192                 return NULL;
 193
 194         if (sdi->status == SR_ST_ACTIVE)
 195                 /* already in use */
 196                 return NULL;
 197
 198         skip = 0;
 199         libusb_get_device_list(usb_context, &devlist);
 200         for (i = 0; devlist[i]; i++) {
 201                 if ((err = libusb_get_device_descriptor(devlist[i], &des))) {
 202                         sr_warn("failed to get device descriptor: %d", err);
 203                         continue;
 204                 }
 205
 206                 if (des.idVendor != fx2->fw_vid || des.idProduct != fx2->fw_pid)
 207                         continue;
 208
 209                 if (sdi->status == SR_ST_INITIALIZING) {
 210                         if (skip != device_index) {
 211                                 /* Skip devices of this type that aren't the one we want. */
 212                                 skip += 1;
 213                                 continue;
 214                         }
 215                 } else if (sdi->status == SR_ST_INACTIVE) {
 216                         /*
 217                          * This device is fully enumerated, so we need to find this
 218                          * device by vendor, product, bus and address.
 219                          */
 220                         if (libusb_get_bus_number(devlist[i]) != sdi->usb->bus
 221                                 || libusb_get_device_address(devlist[i]) != sdi->usb->address)
 222                                 /* this is not the one */
 223                                 continue;
 224                 }
 225
 226                 if (!(err = libusb_open(devlist[i], &sdi->usb->devhdl))) {
 227                         if (sdi->usb->address == 0xff)
 228                                 /*
 229                                  * first time we touch this device after firmware upload,
 230                                  * so we don't know the address yet.
 231                                  */
 232                                 sdi->usb->address = libusb_get_device_address(devlist[i]);
 233
 234                         sdi->status = SR_ST_ACTIVE;
 235                         sr_info("saleae: opened device %d on %d.%d interface %d",
 236                                   sdi->index, sdi->usb->bus,
 237                                   sdi->usb->address, USB_INTERFACE);
 238                 } else {
 239                         sr_warn("failed to open device: %d", err);
 240                         sdi = NULL;
 241                 }
 242         }
 243         libusb_free_device_list(devlist, 1);
 244
 245         if (sdi && sdi->status != SR_ST_ACTIVE)
 246                 sdi = NULL;
 247
 248         return sdi;
 249 }
 250
 251 static int upload_firmware(libusb_device *dev)
 252 {
 253         int ret;
 254
 255         ret = ezusb_upload_firmware(dev, USB_CONFIGURATION, FIRMWARE);
 256         if (ret != 0)
 257                 return 1;
 258
 259         /* Remember when the last firmware update was done. */
 260         g_get_current_time(&fw_updated);
 261
 262         return 0;
 263 }
 264
 265 static void close_device(struct sr_device_instance *sdi)
 266 {
 267         if (sdi->usb->devhdl == NULL)
 268                 return;
 269
 270         sr_info("saleae: closing device %d on %d.%d interface %d", sdi->index,
 271                 sdi->usb->bus, sdi->usb->address, USB_INTERFACE);
 272         libusb_release_interface(sdi->usb->devhdl, USB_INTERFACE);
 273         libusb_close(sdi->usb->devhdl);
 274         sdi->usb->devhdl = NULL;
 275         sdi->status = SR_ST_INACTIVE;
 276 }
 277
 278 static int configure_probes(GSList *probes)
 279 {
 280         struct sr_probe *probe;
 281         GSList *l;
 282         int probe_bit, stage, i;
 283         char *tc;
 284
 285         probe_mask = 0;
 286         for (i = 0; i < NUM_TRIGGER_STAGES; i++) {
 287                 trigger_mask[i] = 0;
 288                 trigger_value[i] = 0;
 289         }
 290
 291         stage = -1;
 292         for (l = probes; l; l = l->next) {
 293                 probe = (struct sr_probe *)l->data;
 294                 if (probe->enabled == FALSE)
 295                         continue;
 296                 probe_bit = 1 << (probe->index - 1);
 297                 probe_mask |= probe_bit;
 298                 if (!(probe->trigger))
 299                         continue;
 300
 301                 stage = 0;
 302                 for (tc = probe->trigger; *tc; tc++) {
 303                         trigger_mask[stage] |= probe_bit;
 304                         if (*tc == '1')
 305                                 trigger_value[stage] |= probe_bit;
 306                         stage++;
 307                         if (stage > NUM_TRIGGER_STAGES)
 308                                 return SR_ERR;
 309                 }
 310         }
 311
 312         if (stage == -1)
 313                 /*
 314                  * We didn't configure any triggers, make sure acquisition
 315                  * doesn't wait for any.
 316                  */
 317                 trigger_stage = TRIGGER_FIRED;
 318         else
 319                 trigger_stage = 0;
 320
 321         return SR_OK;
 322 }
 323
 324 /*
 325  * API callbacks
 326  */
 327
 328 static int hw_init(const char *deviceinfo)
 329 {
 330         struct sr_device_instance *sdi;
 331         struct libusb_device_descriptor des;
 332         libusb_device **devlist;
 333         int err, devcnt, i, j;
 334
 335         /* Avoid compiler warnings. */
 336         deviceinfo = deviceinfo;
 337
 338         if (libusb_init(&usb_context) != 0) {
 339                 sr_warn("Failed to initialize USB.");
 340                 return 0;
 341         }
 342
 343         /* Find all Saleae Logic devices and upload firmware to all of them. */
 344         fx2 = NULL;
 345         devcnt = 0;
 346         libusb_get_device_list(usb_context, &devlist);
 347         for (i = 0; devlist[i]; i++) {
 348                 err = libusb_get_device_descriptor(devlist[i], &des);
 349                 if (err != 0) {
 350                         sr_warn("failed to get device descriptor: %d", err);
 351                         continue;
 352                 }
 353
 354                 for (j = 0; supported_fx2[j].orig_vid; j++) {
 355                         if (des.idVendor == supported_fx2[j].orig_vid
 356                                 && des.idProduct == supported_fx2[j].orig_pid) {
 357                                 fx2 = &supported_fx2[j];
 358                                 break;
 359                         }
 360                 }
 361                 if (!fx2)
 362                         /* not a supported VID/PID */
 363                         continue;
 364
 365                 sdi = sr_device_instance_new(devcnt, SR_ST_INITIALIZING,
 366                         fx2->vendor, fx2->model, fx2->model_version);
 367                 if (!sdi)
 368                         return 0;
 369                 device_instances = g_slist_append(device_instances, sdi);
 370
 371                 if (check_conf_profile(devlist[i]) == 0) {
 372                         /*
 373                          * Continue on the off chance that the device is in a
 374                          * working state. TODO: Could maybe try a USB reset,
 375                          * or uploading the firmware again.
 376                          */
 377                         if (upload_firmware(devlist[i]) > 0)
 378                                 sr_warn("firmware upload failed for device %d",
 379                                         devcnt);
 380
 381                         sdi->usb = sr_usb_device_instance_new
 382                                 (libusb_get_bus_number(devlist[i]), 0xff, NULL);
 383                 } else {
 384                         /* Already has the firmware, so fix the new address. */
 385                         sdi->status = SR_ST_INACTIVE;
 386                         sdi->usb = sr_usb_device_instance_new
 387                             (libusb_get_bus_number(devlist[i]),
 388                              libusb_get_device_address(devlist[i]), NULL);
 389                 }
 390                 devcnt++;
 391
 392                 /* not supporting multiple FX2s in this driver yet */
 393                 break;
 394         }
 395         libusb_free_device_list(devlist, 1);
 396
 397         return devcnt;
 398 }
 399
 400 static int hw_opendev(int device_index)
 401 {
 402         GTimeVal cur_time;
 403         struct sr_device_instance *sdi;
 404         int timediff, err;
 405
 406         /*
 407          * if the firmware was recently uploaded, wait up to MAX_RENUM_DELAY ms
 408          * for the FX2 to renumerate
 409          */
 410         sdi = NULL;
 411         if (fw_updated.tv_sec > 0) {
 412                 sr_info("saleae: waiting for device to reset");
 413                 /* takes at least 300ms for the FX2 to be gone from the USB bus */
 414                 g_usleep(300*1000);
 415                 timediff = 0;
 416                 while (timediff < MAX_RENUM_DELAY) {
 417                         if ((sdi = sl_open_device(device_index)))
 418                                 break;
 419                         g_usleep(100*1000);
 420                         g_get_current_time(&cur_time);
 421                         timediff = GTV_TO_MSEC(cur_time) - GTV_TO_MSEC(fw_updated);
 422                 }
 423                 sr_info("saleae: device came back after %d ms", timediff);
 424         } else {
 425                 sdi = sl_open_device(device_index);
 426         }
 427
 428         if (!sdi) {
 429                 sr_warn("unable to open device");
 430                 return SR_ERR;
 431         }
 432
 433         err = libusb_claim_interface(sdi->usb->devhdl, USB_INTERFACE);
 434         if (err != 0) {
 435                 sr_warn("Unable to claim interface: %d", err);
 436                 return SR_ERR;
 437         }
 438
 439         if (cur_samplerate == 0) {
 440                 /* Samplerate hasn't been set; default to the slowest one. */
 441                 if (hw_set_configuration(device_index, SR_HWCAP_SAMPLERATE,
 442                     &supported_samplerates[0]) == SR_ERR)
 443                         return SR_ERR;
 444         }
 445
 446         return SR_OK;
 447 }
 448
 449 static int hw_closedev(int device_index)
 450 {
 451         struct sr_device_instance *sdi;
 452
 453         if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
 454                 sr_err("logic: %s: sdi was NULL", __func__);
 455                 return SR_ERR; /* TODO: SR_ERR_ARG? */
 456         }
 457
 458         /* TODO */
 459         close_device(sdi);
 460
 461         return SR_OK;
 462 }
 463
 464 static void hw_cleanup(void)
 465 {
 466         GSList *l;
 467
 468         /* Properly close all devices... */
 469         for (l = device_instances; l; l = l->next)
 470                 close_device((struct sr_device_instance *)l->data);
 471
 472         /* ...and free all their memory. */
 473         for (l = device_instances; l; l = l->next)
 474                 g_free(l->data);
 475         g_slist_free(device_instances);
 476         device_instances = NULL;
 477
 478         if (usb_context)
 479                 libusb_exit(usb_context);
 480         usb_context = NULL;
 481 }
 482
 483 static void *hw_get_device_info(int device_index, int device_info_id)
 484 {
 485         struct sr_device_instance *sdi;
 486         void *info = NULL;
 487
 488         if (!(sdi = sr_get_device_instance(device_instances, device_index)))
 489                 return NULL;
 490
 491         switch (device_info_id) {
 492         case SR_DI_INSTANCE:
 493                 info = sdi;
 494                 break;
 495         case SR_DI_NUM_PROBES:
 496                 info = GINT_TO_POINTER(fx2->num_probes);
 497                 break;
 498         case SR_DI_SAMPLERATES:
 499                 info = &samplerates;
 500                 break;
 501         case SR_DI_TRIGGER_TYPES:
 502                 info = TRIGGER_TYPES;
 503                 break;
 504         case SR_DI_CUR_SAMPLERATE:
 505                 info = &cur_samplerate;
 506                 break;
 507         }
 508
 509         return info;
 510 }
 511
 512 static int hw_get_status(int device_index)
 513 {
 514         struct sr_device_instance *sdi;
 515
 516         sdi = sr_get_device_instance(device_instances, device_index);
 517         if (sdi)
 518                 return sdi->status;
 519         else
 520                 return SR_ST_NOT_FOUND;
 521 }
 522
 523 static int *hw_get_capabilities(void)
 524 {
 525         return capabilities;
 526 }
 527
 528 static int set_configuration_samplerate(struct sr_device_instance *sdi,
 529                                         uint64_t samplerate)
 530 {
 531         uint8_t divider;
 532         int ret, result, i;
 533         unsigned char buf[2];
 534
 535         for (i = 0; supported_samplerates[i]; i++) {
 536                 if (supported_samplerates[i] == samplerate)
 537                         break;
 538         }
 539         if (supported_samplerates[i] == 0)
 540                 return SR_ERR_SAMPLERATE;
 541
 542         divider = (uint8_t) (48 / (samplerate / 1000000.0)) - 1;
 543
 544         sr_info("saleae: setting samplerate to %" PRIu64 " Hz (divider %d)",
 545                 samplerate, divider);
 546         buf[0] = 0x01;
 547         buf[1] = divider;
 548         ret = libusb_bulk_transfer(sdi->usb->devhdl, 1 | LIBUSB_ENDPOINT_OUT,
 549                                    buf, 2, &result, 500);
 550         if (ret != 0) {
 551                 sr_warn("failed to set samplerate: %d", ret);
 552                 return SR_ERR;
 553         }
 554         cur_samplerate = samplerate;
 555
 556         return SR_OK;
 557 }
 558
 559 static int hw_set_configuration(int device_index, int capability, void *value)
 560 {
 561         struct sr_device_instance *sdi;
 562         int ret;
 563         uint64_t *tmp_u64;
 564
 565         if (!(sdi = sr_get_device_instance(device_instances, device_index)))
 566                 return SR_ERR;
 567
 568         if (capability == SR_HWCAP_SAMPLERATE) {
 569                 tmp_u64 = value;
 570                 ret = set_configuration_samplerate(sdi, *tmp_u64);
 571         } else if (capability == SR_HWCAP_PROBECONFIG) {
 572                 ret = configure_probes((GSList *) value);
 573         } else if (capability == SR_HWCAP_LIMIT_SAMPLES) {
 574                 tmp_u64 = value;
 575                 limit_samples = *tmp_u64;
 576                 ret = SR_OK;
 577         } else {
 578                 ret = SR_ERR;
 579         }
 580
 581         return ret;
 582 }
 583
 584 static int receive_data(int fd, int revents, void *user_data)
 585 {
 586         struct timeval tv;
 587
 588         /* Avoid compiler warnings. */
 589         fd = fd;
 590         revents = revents;
 591         user_data = user_data;
 592
 593         tv.tv_sec = tv.tv_usec = 0;
 594         libusb_handle_events_timeout(usb_context, &tv);
 595
 596         return TRUE;
 597 }
 598
 599 void receive_transfer(struct libusb_transfer *transfer)
 600 {
 601         static int num_samples = 0;
 602         static int empty_transfer_count = 0;
 603         struct sr_datafeed_packet packet;
 604         void *user_data;
 605         int cur_buflen, trigger_offset, i;
 606         unsigned char *cur_buf, *new_buf;
 607
 608         /* hw_stop_acquisition() is telling us to stop. */
 609         if (transfer == NULL)
 610                 num_samples = -1;
 611
 612         /*
 613          * If acquisition has already ended, just free any queued up
 614          * transfer that come in.
 615          */
 616         if (num_samples == -1) {
 617                 if (transfer)
 618                         libusb_free_transfer(transfer);
 619                 return;
 620         }
 621
 622         sr_info("saleae: receive_transfer(): status %d received %d bytes",
 623                 transfer->status, transfer->actual_length);
 624
 625         /* Save incoming transfer before reusing the transfer struct. */
 626         cur_buf = transfer->buffer;
 627         cur_buflen = transfer->actual_length;
 628         user_data = transfer->user_data;
 629
 630         /* Fire off a new request. */
 631         if (!(new_buf = g_try_malloc(4096))) {
 632                 sr_err("saleae: %s: new_buf malloc failed", __func__);
 633                 // return SR_ERR_MALLOC;
 634                 return; /* FIXME */
 635         }
 636
 637         transfer->buffer = new_buf;
 638         transfer->length = 4096;
 639         if (libusb_submit_transfer(transfer) != 0) {
 640                 /* TODO: Stop session? */
 641                 sr_warn("eek");
 642         }
 643
 644         if (cur_buflen == 0) {
 645                 empty_transfer_count++;
 646                 if (empty_transfer_count > MAX_EMPTY_TRANSFERS) {
 647                         /*
 648                          * The FX2 gave up. End the acquisition, the frontend
 649                          * will work out that the samplecount is short.
 650                          */
 651                         hw_stop_acquisition(-1, user_data);
 652                 }
 653                 return;
 654         } else {
 655                 empty_transfer_count = 0;
 656         }
 657
 658         trigger_offset = 0;
 659         if (trigger_stage >= 0) {
 660                 for (i = 0; i < cur_buflen; i++) {
 661
 662                         if ((cur_buf[i] & trigger_mask[trigger_stage]) == trigger_value[trigger_stage]) {
 663                                 /* Match on this trigger stage. */
 664                                 trigger_buffer[trigger_stage] = cur_buf[i];
 665                                 trigger_stage++;
 666                                 if (trigger_stage == NUM_TRIGGER_STAGES || trigger_mask[trigger_stage] == 0) {
 667                                         /* Match on all trigger stages, we're done. */
 668                                         trigger_offset = i + 1;
 669
 670                                         /*
 671                                          * TODO: Send pre-trigger buffer to session bus.
 672                                          * Tell the frontend we hit the trigger here.
 673                                          */
 674                                         packet.type = SR_DF_TRIGGER;
 675                                         packet.length = 0;
 676                                         sr_session_bus(user_data, &packet);
 677
 678                                         /*
 679                                          * Send the samples that triggered it, since we're
 680                                          * skipping past them.
 681                                          */
 682                                         packet.type = SR_DF_LOGIC;
 683                                         packet.length = trigger_stage;
 684                                         packet.unitsize = 1;
 685                                         packet.payload = trigger_buffer;
 686                                         sr_session_bus(user_data, &packet);
 687
 688                                         trigger_stage = TRIGGER_FIRED;
 689                                         break;
 690                                 }
 691                                 return;
 692                         }
 693
 694                         /*
 695                          * We had a match before, but not in the next sample. However, we may
 696                          * have a match on this stage in the next bit -- trigger on 0001 will
 697                          * fail on seeing 00001, so we need to go back to stage 0 -- but at
 698                          * the next sample from the one that matched originally, which the
 699                          * counter increment at the end of the loop takes care of.
 700                          */
 701                         if (trigger_stage > 0) {
 702                                 i -= trigger_stage;
 703                                 if (i < -1)
 704                                         i = -1; /* Oops, went back past this buffer. */
 705                                 /* Reset trigger stage. */
 706                                 trigger_stage = 0;
 707                         }
 708
 709
 710                 }
 711         }
 712
 713         if (trigger_stage == TRIGGER_FIRED) {
 714                 /* Send the incoming transfer to the session bus. */
 715                 packet.type = SR_DF_LOGIC;
 716                 packet.length = cur_buflen - trigger_offset;
 717                 packet.unitsize = 1;
 718                 packet.payload = cur_buf + trigger_offset;
 719                 sr_session_bus(user_data, &packet);
 720                 g_free(cur_buf);
 721
 722                 num_samples += cur_buflen;
 723                 if (limit_samples && (unsigned int) num_samples > limit_samples) {
 724                         hw_stop_acquisition(-1, user_data);
 725                 }
 726         } else {
 727                 /*
 728                  * TODO: Buffer pre-trigger data in capture
 729                  * ratio-sized buffer.
 730                  */
 731         }
 732 }
 733
 734 static int hw_start_acquisition(int device_index, gpointer session_device_id)
 735 {
 736         struct sr_device_instance *sdi;
 737         struct sr_datafeed_packet *packet;
 738         struct sr_datafeed_header *header;
 739         struct libusb_transfer *transfer;
 740         const struct libusb_pollfd **lupfd;
 741         int size, i;
 742         unsigned char *buf;
 743
 744         if (!(sdi = sr_get_device_instance(device_instances, device_index)))
 745                 return SR_ERR;
 746
 747         if (!(packet = g_try_malloc(sizeof(struct sr_datafeed_packet)))) {
 748                 sr_err("saleae: %s: packet malloc failed", __func__);
 749                 return SR_ERR_MALLOC;
 750         }
 751
 752         if (!(header = g_try_malloc(sizeof(struct sr_datafeed_header)))) {
 753                 sr_err("saleae: %s: header malloc failed", __func__);
 754                 return SR_ERR_MALLOC;
 755         }
 756
 757         /* Start with 2K transfer, subsequently increased to 4K. */
 758         size = 2048;
 759         for (i = 0; i < NUM_SIMUL_TRANSFERS; i++) {
 760                 if (!(buf = g_try_malloc(size))) {
 761                         sr_err("saleae: %s: buf malloc failed", __func__);
 762                         return SR_ERR_MALLOC;
 763                 }
 764                 transfer = libusb_alloc_transfer(0);
 765                 libusb_fill_bulk_transfer(transfer, sdi->usb->devhdl,
 766                                 2 | LIBUSB_ENDPOINT_IN, buf, size,
 767                                 receive_transfer, session_device_id, 40);
 768                 if (libusb_submit_transfer(transfer) != 0) {
 769                         /* TODO: Free them all. */
 770                         libusb_free_transfer(transfer);
 771                         g_free(buf);
 772                         return SR_ERR;
 773                 }
 774                 size = 4096;
 775         }
 776
 777         lupfd = libusb_get_pollfds(usb_context);
 778         for (i = 0; lupfd[i]; i++)
 779                 sr_source_add(lupfd[i]->fd, lupfd[i]->events, 40, receive_data,
 780                               NULL);
 781         free(lupfd);
 782
 783         packet->type = SR_DF_HEADER;
 784         packet->length = sizeof(struct sr_datafeed_header);
 785         packet->payload = (unsigned char *)header;
 786         header->feed_version = 1;
 787         gettimeofday(&header->starttime, NULL);
 788         header->samplerate = cur_samplerate;
 789         header->protocol_id = SR_PROTO_RAW;
 790         header->num_logic_probes = fx2->num_probes;
 791         header->num_analog_probes = 0;
 792         sr_session_bus(session_device_id, packet);
 793         g_free(header);
 794         g_free(packet);
 795
 796         return SR_OK;
 797 }
 798
 799 /* This stops acquisition on ALL devices, ignoring device_index. */
 800 static void hw_stop_acquisition(int device_index, gpointer session_device_id)
 801 {
 802         struct sr_datafeed_packet packet;
 803
 804         /* Avoid compiler warnings. */
 805         device_index = device_index;
 806
 807         packet.type = SR_DF_END;
 808         sr_session_bus(session_device_id, &packet);
 809
 810         receive_transfer(NULL);
 811
 812         /* TODO: Need to cancel and free any queued up transfers. */
 813 }
 814
 815 struct sr_device_plugin saleae_logic_plugin_info = {
 816         .name = "saleae-logic",
 817         .longname = "Saleae Logic",
 818         .api_version = 1,
 819         .init = hw_init,
 820         .cleanup = hw_cleanup,
 821         .opendev = hw_opendev,
 822         .closedev = hw_closedev,
 823         .get_device_info = hw_get_device_info,
 824         .get_status = hw_get_status,
 825         .get_capabilities = hw_get_capabilities,
 826         .set_configuration = hw_set_configuration,
 827         .start_acquisition = hw_start_acquisition,
 828         .stop_acquisition = hw_stop_acquisition,
 829 };