src/hardware/openbench-logic-sniffer/protocol.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2013 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 "protocol.h"
  22
  23 struct ols_basic_trigger_desc {
  24         uint32_t trigger_mask[NUM_BASIC_TRIGGER_STAGES];
  25         uint32_t trigger_value[NUM_BASIC_TRIGGER_STAGES];
  26         int num_stages;
  27 };
  28
  29 SR_PRIV int send_shortcommand(struct sr_serial_dev_inst *serial,
  30                               uint8_t command)
  31 {
  32         char buf[1];
  33
  34         sr_dbg("Sending cmd 0x%.2x.", command);
  35         buf[0] = command;
  36         if (serial_write_blocking(serial, buf, 1, serial_timeout(serial, 1)) != 1)
  37                 return SR_ERR;
  38
  39         if (serial_drain(serial) != SR_OK)
  40                 return SR_ERR;
  41
  42         return SR_OK;
  43 }
  44
  45 SR_PRIV int send_longcommand(struct sr_serial_dev_inst *serial, uint8_t command,
  46                              uint8_t *data)
  47 {
  48         char buf[5];
  49
  50         sr_dbg("Sending cmd 0x%.2x data 0x%.2x%.2x%.2x%.2x.", command, data[0],
  51                data[1], data[2], data[3]);
  52         buf[0] = command;
  53         buf[1] = data[0];
  54         buf[2] = data[1];
  55         buf[3] = data[2];
  56         buf[4] = data[3];
  57         if (serial_write_blocking(serial, buf, 5, serial_timeout(serial, 1)) != 5)
  58                 return SR_ERR;
  59
  60         if (serial_drain(serial) != SR_OK)
  61                 return SR_ERR;
  62
  63         return SR_OK;
  64 }
  65
  66 static int ols_send_longdata(struct sr_serial_dev_inst *serial, uint8_t command,
  67                              uint32_t value)
  68 {
  69         uint8_t data[4];
  70         WL32(data, value);
  71         return send_longcommand(serial, command, data);
  72 }
  73
  74 SR_PRIV int ols_send_reset(struct sr_serial_dev_inst *serial)
  75 {
  76         unsigned int i;
  77
  78         for (i = 0; i < 5; i++) {
  79                 if (send_shortcommand(serial, CMD_RESET) != SR_OK)
  80                         return SR_ERR;
  81         }
  82
  83         return SR_OK;
  84 }
  85
  86 /* Configures the channel mask based on which channels are enabled. */
  87 SR_PRIV uint32_t ols_channel_mask(const struct sr_dev_inst *sdi)
  88 {
  89         uint32_t channel_mask = 0;
  90         for (const GSList *l = sdi->channels; l; l = l->next) {
  91                 struct sr_channel *channel = l->data;
  92                 if (channel->enabled)
  93                         channel_mask |= 1 << channel->index;
  94         }
  95
  96         return channel_mask;
  97 }
  98
  99 static int convert_trigger(const struct sr_dev_inst *sdi,
 100                            struct ols_basic_trigger_desc *ols_trigger)
 101 {
 102         struct sr_trigger *trigger;
 103         struct sr_trigger_stage *stage;
 104         struct sr_trigger_match *match;
 105         const GSList *l, *m;
 106         int i;
 107
 108         ols_trigger->num_stages = 0;
 109         for (i = 0; i < NUM_BASIC_TRIGGER_STAGES; i++) {
 110                 ols_trigger->trigger_mask[i] = 0;
 111                 ols_trigger->trigger_value[i] = 0;
 112         }
 113
 114         if (!(trigger = sr_session_trigger_get(sdi->session)))
 115                 return SR_OK;
 116
 117         ols_trigger->num_stages = g_slist_length(trigger->stages);
 118         if (ols_trigger->num_stages > NUM_BASIC_TRIGGER_STAGES) {
 119                 sr_err("This device only supports %d trigger stages.",
 120                        NUM_BASIC_TRIGGER_STAGES);
 121                 return SR_ERR;
 122         }
 123
 124         for (l = trigger->stages; l; l = l->next) {
 125                 stage = l->data;
 126                 for (m = stage->matches; m; m = m->next) {
 127                         match = m->data;
 128                         if (!match->channel->enabled)
 129                                 /* Ignore disabled channels with a trigger. */
 130                                 continue;
 131                         ols_trigger->trigger_mask[stage->stage] |=
 132                                 1 << match->channel->index;
 133                         if (match->match == SR_TRIGGER_ONE)
 134                                 ols_trigger->trigger_value[stage->stage] |=
 135                                         1 << match->channel->index;
 136                 }
 137         }
 138
 139         return SR_OK;
 140 }
 141
 142 static void ols_metadata_quirks(struct sr_dev_inst *sdi)
 143 {
 144         struct dev_context *devc;
 145         gboolean is_shrimp;
 146
 147         if (!sdi)
 148                 return;
 149         devc = sdi->priv;
 150         if (!devc)
 151                 return;
 152
 153         is_shrimp = sdi->model && strcmp(sdi->model, "Shrimp1.0") == 0;
 154         if (is_shrimp) {
 155                 if (!devc->max_channels)
 156                         devc->max_channels = 4;
 157                 if (!devc->max_samples)
 158                         devc->max_samples = 256 * 1024;
 159                 if (!devc->max_samplerate)
 160                         devc->max_samplerate = SR_MHZ(20);
 161         }
 162
 163         if (sdi->version && strstr(sdi->version, "FPGA version 3.07"))
 164                 devc->device_flags |= DEVICE_FLAG_IS_DEMON_CORE;
 165 }
 166
 167 SR_PRIV int ols_get_metadata(struct sr_dev_inst *sdi)
 168 {
 169         struct sr_serial_dev_inst *serial;
 170         struct dev_context *devc;
 171         uint32_t tmp_int;
 172         uint8_t key, type;
 173         int delay_ms;
 174         GString *tmp_str, *devname, *version;
 175         guchar tmp_c;
 176
 177         serial = sdi->conn;
 178         devc = sdi->priv;
 179
 180         devname = g_string_new("");
 181         version = g_string_new("");
 182
 183         key = 0xff;
 184         while (key) {
 185                 delay_ms = serial_timeout(serial, 1);
 186                 if (serial_read_blocking(serial, &key, 1, delay_ms) != 1)
 187                         break;
 188                 if (key == METADATA_TOKEN_END) {
 189                         sr_dbg("Got metadata key 0x00, metadata ends.");
 190                         break;
 191                 }
 192                 type = key >> 5;
 193                 switch (type) {
 194                 case 0:
 195                         /* NULL-terminated string */
 196                         tmp_str = g_string_new("");
 197                         delay_ms = serial_timeout(serial, 1);
 198                         while (serial_read_blocking(serial, &tmp_c, 1,
 199                                                     delay_ms) == 1 &&
 200                                tmp_c != '\0')
 201                                 g_string_append_c(tmp_str, tmp_c);
 202                         sr_dbg("Got metadata token 0x%.2x value '%s'.", key,
 203                                tmp_str->str);
 204                         switch (key) {
 205                         case METADATA_TOKEN_DEVICE_NAME:
 206                                 /* Device name */
 207                                 devname =
 208                                         g_string_append(devname, tmp_str->str);
 209                                 break;
 210                         case METADATA_TOKEN_FPGA_VERSION:
 211                                 /* FPGA firmware version */
 212                                 if (version->len)
 213                                         g_string_append(version, ", ");
 214                                 g_string_append(version, "FPGA version ");
 215                                 g_string_append(version, tmp_str->str);
 216                                 break;
 217                         case METADATA_TOKEN_ANCILLARY_VERSION:
 218                                 /* Ancillary version */
 219                                 if (version->len)
 220                                         g_string_append(version, ", ");
 221                                 g_string_append(version, "Ancillary version ");
 222                                 g_string_append(version, tmp_str->str);
 223                                 break;
 224                         default:
 225                                 sr_info("ols: unknown token 0x%.2x: '%s'", key,
 226                                         tmp_str->str);
 227                                 break;
 228                         }
 229                         g_string_free(tmp_str, TRUE);
 230                         break;
 231                 case 1:
 232                         /* 32-bit unsigned integer */
 233                         delay_ms = serial_timeout(serial, 4);
 234                         if (serial_read_blocking(serial, &tmp_int, 4,
 235                                                  delay_ms) != 4)
 236                                 break;
 237                         tmp_int = RB32(&tmp_int);
 238                         sr_dbg("Got metadata token 0x%.2x value 0x%.8x.", key,
 239                                tmp_int);
 240                         switch (key) {
 241                         case METADATA_TOKEN_NUM_PROBES_LONG:
 242                                 /* Number of usable channels */
 243                                 devc->max_channels = tmp_int;
 244                                 break;
 245                         case METADATA_TOKEN_SAMPLE_MEMORY_BYTES:
 246                                 /* Amount of sample memory available (bytes) */
 247                                 devc->max_samples = tmp_int;
 248                                 break;
 249                         case METADATA_TOKEN_DYNAMIC_MEMORY_BYTES:
 250                                 /* Amount of dynamic memory available (bytes) */
 251                                 /* what is this for? */
 252                                 break;
 253                         case METADATA_TOKEN_MAX_SAMPLE_RATE_HZ:
 254                                 /* Maximum sample rate (Hz) */
 255                                 devc->max_samplerate = tmp_int;
 256                                 break;
 257                         case METADATA_TOKEN_PROTOCOL_VERSION_LONG:
 258                                 /* protocol version */
 259                                 devc->protocol_version = tmp_int;
 260                                 break;
 261                         default:
 262                                 sr_info("Unknown token 0x%.2x: 0x%.8x.", key,
 263                                         tmp_int);
 264                                 break;
 265                         }
 266                         break;
 267                 case 2:
 268                         /* 8-bit unsigned integer */
 269                         delay_ms = serial_timeout(serial, 1);
 270                         if (serial_read_blocking(serial, &tmp_c, 1, delay_ms) != 1)
 271                                 break;
 272                         sr_dbg("Got metadata token 0x%.2x value 0x%.2x.", key,
 273                                tmp_c);
 274                         switch (key) {
 275                         case METADATA_TOKEN_NUM_PROBES_SHORT:
 276                                 /* Number of usable channels */
 277                                 devc->max_channels = tmp_c;
 278                                 break;
 279                         case METADATA_TOKEN_PROTOCOL_VERSION_SHORT:
 280                                 /* protocol version */
 281                                 devc->protocol_version = tmp_c;
 282                                 break;
 283                         default:
 284                                 sr_info("Unknown token 0x%.2x: 0x%.2x.", key,
 285                                         tmp_c);
 286                                 break;
 287                         }
 288                         break;
 289                 default:
 290                         /* unknown type */
 291                         break;
 292                 }
 293         }
 294
 295         sdi->model = g_string_free(devname, FALSE);
 296         sdi->version = g_string_free(version, FALSE);
 297
 298         /* Optionally amend received metadata, model specific quirks. */
 299         ols_metadata_quirks(sdi);
 300
 301         return SR_OK;
 302 }
 303
 304 SR_PRIV int ols_set_samplerate(const struct sr_dev_inst *sdi,
 305                                const uint64_t samplerate)
 306 {
 307         struct dev_context *devc;
 308
 309         devc = sdi->priv;
 310         if (devc->max_samplerate && samplerate > devc->max_samplerate)
 311                 return SR_ERR_SAMPLERATE;
 312
 313         if (samplerate > CLOCK_RATE) {
 314                 sr_info("Enabling demux mode.");
 315                 devc->capture_flags |= CAPTURE_FLAG_DEMUX;
 316                 devc->capture_flags &= ~CAPTURE_FLAG_NOISE_FILTER;
 317                 devc->cur_samplerate_divider =
 318                         (CLOCK_RATE * 2 / samplerate) - 1;
 319         } else {
 320                 sr_info("Disabling demux mode.");
 321                 devc->capture_flags &= ~CAPTURE_FLAG_DEMUX;
 322                 devc->capture_flags |= CAPTURE_FLAG_NOISE_FILTER;
 323                 devc->cur_samplerate_divider = (CLOCK_RATE / samplerate) - 1;
 324         }
 325
 326         /* Calculate actual samplerate used and complain if it is different
 327          * from the requested.
 328          */
 329         devc->cur_samplerate = CLOCK_RATE / (devc->cur_samplerate_divider + 1);
 330         if (devc->capture_flags & CAPTURE_FLAG_DEMUX)
 331                 devc->cur_samplerate *= 2;
 332         if (devc->cur_samplerate != samplerate)
 333                 sr_info("Can't match samplerate %" PRIu64 ", using %" PRIu64
 334                         ".",
 335                         samplerate, devc->cur_samplerate);
 336
 337         return SR_OK;
 338 }
 339
 340 SR_PRIV void abort_acquisition(const struct sr_dev_inst *sdi)
 341 {
 342         struct sr_serial_dev_inst *serial;
 343
 344         serial = sdi->conn;
 345         ols_send_reset(serial);
 346
 347         serial_source_remove(sdi->session, serial);
 348
 349         std_session_send_df_end(sdi);
 350 }
 351
 352 SR_PRIV int ols_receive_data(int fd, int revents, void *cb_data)
 353 {
 354         struct dev_context *devc;
 355         struct sr_dev_inst *sdi;
 356         struct sr_serial_dev_inst *serial;
 357         struct sr_datafeed_packet packet;
 358         struct sr_datafeed_logic logic;
 359         uint32_t sample;
 360         int num_changroups, offset, j;
 361         unsigned int i;
 362         unsigned char byte;
 363
 364         (void)fd;
 365
 366         sdi = cb_data;
 367         serial = sdi->conn;
 368         devc = sdi->priv;
 369
 370         if (devc->num_transfers == 0 && revents == 0) {
 371                 /* Ignore timeouts as long as we haven't received anything */
 372                 return TRUE;
 373         }
 374
 375         if (devc->num_transfers++ == 0) {
 376                 devc->raw_sample_buf = g_try_malloc(devc->limit_samples * 4);
 377                 if (!devc->raw_sample_buf) {
 378                         sr_err("Sample buffer malloc failed.");
 379                         return FALSE;
 380                 }
 381                 /* fill with 1010... for debugging */
 382                 memset(devc->raw_sample_buf, 0x82, devc->limit_samples * 4);
 383         }
 384
 385         num_changroups = 0;
 386         for (i = 0x20; i > 0x02; i >>= 1) {
 387                 if ((devc->capture_flags & i) == 0) {
 388                         num_changroups++;
 389                 }
 390         }
 391
 392         if (revents == G_IO_IN && devc->num_samples < devc->limit_samples) {
 393                 if (serial_read_nonblocking(serial, &byte, 1) != 1)
 394                         return FALSE;
 395                 devc->cnt_bytes++;
 396
 397                 /* Ignore it if we've read enough. */
 398                 if (devc->num_samples >= devc->limit_samples)
 399                         return TRUE;
 400
 401                 devc->sample[devc->num_bytes++] = byte;
 402                 sr_spew("Received byte 0x%.2x.", byte);
 403                 if (devc->num_bytes == num_changroups) {
 404                         devc->cnt_samples++;
 405                         devc->cnt_samples_rle++;
 406                         /*
 407                          * Got a full sample. Convert from the OLS's little-endian
 408                          * sample to the local format.
 409                          */
 410                         sample = devc->sample[0] | (devc->sample[1] << 8) |
 411                                  (devc->sample[2] << 16) |
 412                                  (devc->sample[3] << 24);
 413                         sr_dbg("Received sample 0x%.*x.", devc->num_bytes * 2,
 414                                sample);
 415                         if (devc->capture_flags & CAPTURE_FLAG_RLE) {
 416                                 /*
 417                                  * In RLE mode the high bit of the sample is the
 418                                  * "count" flag, meaning this sample is the number
 419                                  * of times the previous sample occurred.
 420                                  */
 421                                 if (devc->sample[devc->num_bytes - 1] & 0x80) {
 422                                         /* Clear the high bit. */
 423                                         sample &= ~(0x80 << (devc->num_bytes -
 424                                                              1) * 8);
 425                                         devc->rle_count = sample;
 426                                         devc->cnt_samples_rle +=
 427                                                 devc->rle_count;
 428                                         sr_dbg("RLE count: %u.",
 429                                                devc->rle_count);
 430                                         devc->num_bytes = 0;
 431                                         return TRUE;
 432                                 }
 433                         }
 434                         devc->num_samples += devc->rle_count + 1;
 435                         if (devc->num_samples > devc->limit_samples) {
 436                                 /* Save us from overrunning the buffer. */
 437                                 devc->rle_count -=
 438                                         devc->num_samples - devc->limit_samples;
 439                                 devc->num_samples = devc->limit_samples;
 440                         }
 441
 442                         if (num_changroups < 4) {
 443                                 /*
 444                                  * Some channel groups may have been turned
 445                                  * off, to speed up transfer between the
 446                                  * hardware and the PC. Expand that here before
 447                                  * submitting it over the session bus --
 448                                  * whatever is listening on the bus will be
 449                                  * expecting a full 32-bit sample, based on
 450                                  * the number of channels.
 451                                  */
 452                                 j = 0;
 453                                 uint8_t tmp_sample[4] = { 0, 0, 0, 0 };
 454                                 for (i = 0; i < 4; i++) {
 455                                         if (((devc->capture_flags >> 2) &
 456                                              (1 << i)) == 0) {
 457                                                 /*
 458                                                  * This channel group was
 459                                                  * enabled, copy from received
 460                                                  * sample.
 461                                                  */
 462                                                 tmp_sample[i] =
 463                                                         devc->sample[j++];
 464                                         }
 465                                 }
 466                                 memcpy(devc->sample, tmp_sample, 4);
 467                                 sr_spew("Expanded sample: 0x%.2hhx%.2hhx%.2hhx%.2hhx ",
 468                                         devc->sample[3], devc->sample[2],
 469                                         devc->sample[1], devc->sample[0]);
 470                         }
 471
 472                         /*
 473                          * the OLS sends its sample buffer backwards.
 474                          * store it in reverse order here, so we can dump
 475                          * this on the session bus later.
 476                          */
 477                         offset = (devc->limit_samples - devc->num_samples) * 4;
 478                         for (i = 0; i <= devc->rle_count; i++) {
 479                                 memcpy(devc->raw_sample_buf + offset + (i * 4),
 480                                        devc->sample, 4);
 481                         }
 482                         memset(devc->sample, 0, 4);
 483                         devc->num_bytes = 0;
 484                         devc->rle_count = 0;
 485                 }
 486         } else {
 487                 /*
 488                  * This is the main loop telling us a timeout was reached, or
 489                  * we've acquired all the samples we asked for -- we're done.
 490                  * Send the (properly-ordered) buffer to the frontend.
 491                  */
 492                 sr_dbg("Received %d bytes, %d samples, %d decompressed samples.",
 493                        devc->cnt_bytes, devc->cnt_samples,
 494                        devc->cnt_samples_rle);
 495                 if (devc->trigger_at_smpl != OLS_NO_TRIGGER) {
 496                         /*
 497                          * A trigger was set up, so we need to tell the frontend
 498                          * about it.
 499                          */
 500                         if (devc->trigger_at_smpl > 0) {
 501                                 /* There are pre-trigger samples, send those first. */
 502                                 packet.type = SR_DF_LOGIC;
 503                                 packet.payload = &logic;
 504                                 logic.length = devc->trigger_at_smpl * 4;
 505                                 logic.unitsize = 4;
 506                                 logic.data = devc->raw_sample_buf +
 507                                              (devc->limit_samples -
 508                                               devc->num_samples) *
 509                                                      4;
 510                                 sr_session_send(sdi, &packet);
 511                         }
 512
 513                         /* Send the trigger. */
 514                         std_session_send_df_trigger(sdi);
 515                 }
 516
 517                 /* Send post-trigger / all captured samples. */
 518                 int num_pre_trigger_samples = devc->trigger_at_smpl ==
 519                                                               OLS_NO_TRIGGER ?
 520                                                             0 :
 521                                                             devc->trigger_at_smpl;
 522                 packet.type = SR_DF_LOGIC;
 523                 packet.payload = &logic;
 524                 logic.length =
 525                         (devc->num_samples - num_pre_trigger_samples) * 4;
 526                 logic.unitsize = 4;
 527                 logic.data = devc->raw_sample_buf +
 528                              (num_pre_trigger_samples + devc->limit_samples -
 529                               devc->num_samples) *
 530                                      4;
 531                 sr_session_send(sdi, &packet);
 532
 533                 g_free(devc->raw_sample_buf);
 534
 535                 serial_flush(serial);
 536                 abort_acquisition(sdi);
 537         }
 538
 539         return TRUE;
 540 }
 541
 542 static int
 543 ols_set_basic_trigger_stage(const struct ols_basic_trigger_desc *trigger_desc,
 544                             struct sr_serial_dev_inst *serial, int stage)
 545 {
 546         uint8_t cmd, arg[4];
 547
 548         cmd = CMD_SET_BASIC_TRIGGER_MASK0 + stage * 4;
 549         if (ols_send_longdata(serial, cmd, trigger_desc->trigger_mask[stage]) != SR_OK)
 550                 return SR_ERR;
 551
 552         cmd = CMD_SET_BASIC_TRIGGER_VALUE0 + stage * 4;
 553         if (ols_send_longdata(serial, cmd, trigger_desc->trigger_value[stage]) != SR_OK)
 554                 return SR_ERR;
 555
 556         cmd = CMD_SET_BASIC_TRIGGER_CONFIG0 + stage * 4;
 557         arg[0] = arg[1] = arg[3] = 0x00;
 558         arg[2] = stage;
 559         if (stage == trigger_desc->num_stages - 1)
 560                 /* Last stage, fire when this one matches. */
 561                 arg[3] |= TRIGGER_START;
 562         if (send_longcommand(serial, cmd, arg) != SR_OK)
 563                 return SR_ERR;
 564
 565         return SR_OK;
 566 }
 567
 568 SR_PRIV int ols_prepare_acquisition(const struct sr_dev_inst *sdi)
 569 {
 570         int ret;
 571
 572         struct dev_context *devc = sdi->priv;
 573         struct sr_serial_dev_inst *serial = sdi->conn;
 574
 575         int num_changroups = 0;
 576         uint8_t changroup_mask = 0;
 577         uint32_t channel_mask = ols_channel_mask(sdi);
 578         for (unsigned int i = 0; i < 4; i++) {
 579                 if (channel_mask & (0xff << (i * 8))) {
 580                         changroup_mask |= (1 << i);
 581                         num_changroups++;
 582                 }
 583         }
 584
 585         /*
 586          * Limit readcount to prevent reading past the end of the hardware
 587          * buffer. Rather read too many samples than too few.
 588          */
 589         uint32_t samplecount =
 590                 MIN(devc->max_samples / num_changroups, devc->limit_samples);
 591         uint32_t readcount = (samplecount + 3) / 4;
 592         uint32_t delaycount;
 593
 594         /* Basic triggers. */
 595         struct ols_basic_trigger_desc basic_trigger_desc;
 596         if (convert_trigger(sdi, &basic_trigger_desc) != SR_OK) {
 597                 sr_err("Failed to configure channels.");
 598                 return SR_ERR;
 599         }
 600         if (basic_trigger_desc.num_stages > 0) {
 601                 /*
 602                  * According to http://mygizmos.org/ols/Logic-Sniffer-FPGA-Spec.pdf
 603                  * reset command must be send prior each arm command
 604                  */
 605                 sr_dbg("Send reset command before trigger configure");
 606                 if (ols_send_reset(serial) != SR_OK)
 607                         return SR_ERR;
 608
 609                 delaycount = readcount * (1 - devc->capture_ratio / 100.0);
 610                 devc->trigger_at_smpl = (readcount - delaycount) * 4 -
 611                                         basic_trigger_desc.num_stages;
 612                 for (int i = 0; i < basic_trigger_desc.num_stages; i++) {
 613                         sr_dbg("Setting OLS stage %d trigger.", i);
 614                         if ((ret = ols_set_basic_trigger_stage(
 615                                      &basic_trigger_desc, serial, i)) != SR_OK)
 616                                 return ret;
 617                 }
 618         } else {
 619                 /* No triggers configured, force trigger on first stage. */
 620                 sr_dbg("Forcing trigger at stage 0.");
 621                 basic_trigger_desc.num_stages = 1;
 622                 if ((ret = ols_set_basic_trigger_stage(&basic_trigger_desc,
 623                                                        serial, 0)) != SR_OK)
 624                         return ret;
 625                 delaycount = readcount;
 626         }
 627
 628         /* Samplerate. */
 629         sr_dbg("Setting samplerate to %" PRIu64 "Hz (divider %u)",
 630                devc->cur_samplerate, devc->cur_samplerate_divider);
 631         if (ols_send_longdata(serial, CMD_SET_DIVIDER,
 632                               devc->cur_samplerate_divider & 0x00FFFFFF) != SR_OK)
 633                 return SR_ERR;
 634
 635         /* Send sample limit and pre/post-trigger capture ratio. */
 636         sr_dbg("Setting sample limit %d, trigger point at %d",
 637                (readcount - 1) * 4, (delaycount - 1) * 4);
 638
 639         if (devc->max_samples > 256 * 1024) {
 640                 if (ols_send_longdata(serial, CMD_CAPTURE_READCOUNT,
 641                                       readcount - 1) != SR_OK)
 642                         return SR_ERR;
 643                 if (ols_send_longdata(serial, CMD_CAPTURE_DELAYCOUNT,
 644                                       delaycount - 1) != SR_OK)
 645                         return SR_ERR;
 646         } else {
 647                 uint8_t arg[4];
 648                 WL16(&arg[0], readcount - 1);
 649                 WL16(&arg[2], delaycount - 1);
 650                 if (send_longcommand(serial, CMD_CAPTURE_SIZE, arg) != SR_OK)
 651                         return SR_ERR;
 652         }
 653
 654         /* Flag register. */
 655         sr_dbg("Setting intpat %s, extpat %s, RLE %s, noise_filter %s, demux %s, "
 656                "%s clock%s",
 657                devc->capture_flags & CAPTURE_FLAG_INTERNAL_TEST_MODE ? "on" :
 658                                                                              "off",
 659                devc->capture_flags & CAPTURE_FLAG_EXTERNAL_TEST_MODE ? "on" :
 660                                                                              "off",
 661                devc->capture_flags & CAPTURE_FLAG_RLE ? "on" : "off",
 662                devc->capture_flags & CAPTURE_FLAG_NOISE_FILTER ? "on" : "off",
 663                devc->capture_flags & CAPTURE_FLAG_DEMUX ? "on" : "off",
 664                devc->capture_flags & CAPTURE_FLAG_CLOCK_EXTERNAL ? "external" :
 665                                                                          "internal",
 666                devc->capture_flags & CAPTURE_FLAG_CLOCK_EXTERNAL ?
 667                              (devc->capture_flags & CAPTURE_FLAG_INVERT_EXT_CLOCK ?
 668                                       " on falling edge" :
 669                                       "on rising edge") :
 670                              "");
 671
 672         /*
 673          * Enable/disable OLS channel groups in the flag register according
 674          * to the channel mask. 1 means "disable channel".
 675          */
 676         devc->capture_flags &= ~0x3c;
 677         devc->capture_flags |= ~(changroup_mask << 2) & 0x3c;
 678
 679         /* RLE mode is always zero, for now. */
 680
 681         if (ols_send_longdata(serial, CMD_SET_FLAGS, devc->capture_flags) != SR_OK)
 682                 return SR_ERR;
 683
 684         return SR_OK;
 685 }