src/hardware/demo/api.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
   5  * Copyright (C) 2011 Olivier Fauchon <olivier@aixmarseille.com>
   6  * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
   7  * Copyright (C) 2015 Bartosz Golaszewski <bgolaszewski@baylibre.com>
   8  * Copyright (C) 2019 Frank Stettner <frank-stettner@gmx.net>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 #include <config.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <math.h>
  28 #include <libsigrok/libsigrok.h>
  29 #include "libsigrok-internal.h"
  30 #include "protocol.h"
  31
  32 #define DEFAULT_NUM_LOGIC_CHANNELS              8
  33 #define DEFAULT_LOGIC_PATTERN                   PATTERN_SIGROK
  34
  35 #define DEFAULT_NUM_ANALOG_CHANNELS             5
  36
  37 /* Note: No spaces allowed because of sigrok-cli. */
  38 static const char *logic_pattern_str[] = {
  39         "sigrok",
  40         "random",
  41         "incremental",
  42         "walking-one",
  43         "walking-zero",
  44         "all-low",
  45         "all-high",
  46         "squid",
  47         "graycode",
  48 };
  49
  50 static const uint32_t scanopts[] = {
  51         SR_CONF_NUM_LOGIC_CHANNELS,
  52         SR_CONF_NUM_ANALOG_CHANNELS,
  53         SR_CONF_LIMIT_FRAMES,
  54 };
  55
  56 static const uint32_t drvopts[] = {
  57         SR_CONF_DEMO_DEV,
  58         SR_CONF_LOGIC_ANALYZER,
  59         SR_CONF_OSCILLOSCOPE,
  60 };
  61
  62 static const uint32_t devopts[] = {
  63         SR_CONF_CONTINUOUS,
  64         SR_CONF_LIMIT_SAMPLES | SR_CONF_GET | SR_CONF_SET,
  65         SR_CONF_LIMIT_MSEC | SR_CONF_GET | SR_CONF_SET,
  66         SR_CONF_LIMIT_FRAMES | SR_CONF_GET | SR_CONF_SET,
  67         SR_CONF_SAMPLERATE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
  68         SR_CONF_AVERAGING | SR_CONF_GET | SR_CONF_SET,
  69         SR_CONF_AVG_SAMPLES | SR_CONF_GET | SR_CONF_SET,
  70         SR_CONF_TRIGGER_MATCH | SR_CONF_LIST,
  71         SR_CONF_CAPTURE_RATIO | SR_CONF_GET | SR_CONF_SET,
  72 };
  73
  74 static const uint32_t devopts_cg_logic[] = {
  75         SR_CONF_PATTERN_MODE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
  76 };
  77
  78 static const uint32_t devopts_cg_analog_group[] = {
  79         SR_CONF_AMPLITUDE | SR_CONF_GET | SR_CONF_SET,
  80         SR_CONF_OFFSET | SR_CONF_GET | SR_CONF_SET,
  81 };
  82
  83 static const uint32_t devopts_cg_analog_channel[] = {
  84         SR_CONF_MEASURED_QUANTITY | SR_CONF_GET | SR_CONF_SET,
  85         SR_CONF_PATTERN_MODE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
  86         SR_CONF_AMPLITUDE | SR_CONF_GET | SR_CONF_SET,
  87         SR_CONF_OFFSET | SR_CONF_GET | SR_CONF_SET,
  88 };
  89
  90 static const int32_t trigger_matches[] = {
  91         SR_TRIGGER_ZERO,
  92         SR_TRIGGER_ONE,
  93         SR_TRIGGER_RISING,
  94         SR_TRIGGER_FALLING,
  95         SR_TRIGGER_EDGE,
  96 };
  97
  98 static const uint64_t samplerates[] = {
  99         SR_HZ(1),
 100         SR_GHZ(1),
 101         SR_HZ(1),
 102 };
 103
 104 static GSList *scan(struct sr_dev_driver *di, GSList *options)
 105 {
 106         struct dev_context *devc;
 107         struct sr_dev_inst *sdi;
 108         struct sr_channel *ch;
 109         struct sr_channel_group *cg, *acg;
 110         struct sr_config *src;
 111         struct analog_gen *ag;
 112         GSList *l;
 113         int num_logic_channels, num_analog_channels, pattern, i;
 114         uint64_t limit_frames;
 115         char channel_name[16];
 116
 117         num_logic_channels = DEFAULT_NUM_LOGIC_CHANNELS;
 118         num_analog_channels = DEFAULT_NUM_ANALOG_CHANNELS;
 119         limit_frames = DEFAULT_LIMIT_FRAMES;
 120         for (l = options; l; l = l->next) {
 121                 src = l->data;
 122                 switch (src->key) {
 123                 case SR_CONF_NUM_LOGIC_CHANNELS:
 124                         num_logic_channels = g_variant_get_int32(src->data);
 125                         break;
 126                 case SR_CONF_NUM_ANALOG_CHANNELS:
 127                         num_analog_channels = g_variant_get_int32(src->data);
 128                         break;
 129                 case SR_CONF_LIMIT_FRAMES:
 130                         limit_frames = g_variant_get_uint64(src->data);
 131                         break;
 132                 }
 133         }
 134
 135         sdi = g_malloc0(sizeof(struct sr_dev_inst));
 136         sdi->status = SR_ST_INACTIVE;
 137         sdi->model = g_strdup("Demo device");
 138
 139         devc = g_malloc0(sizeof(struct dev_context));
 140         devc->cur_samplerate = SR_KHZ(200);
 141         devc->num_logic_channels = num_logic_channels;
 142         devc->logic_unitsize = (devc->num_logic_channels + 7) / 8;
 143         devc->all_logic_channels_mask = 1UL << 0;
 144         devc->all_logic_channels_mask <<= devc->num_logic_channels;
 145         devc->all_logic_channels_mask--;
 146         devc->logic_pattern = DEFAULT_LOGIC_PATTERN;
 147         devc->num_analog_channels = num_analog_channels;
 148         devc->limit_frames = limit_frames;
 149         devc->capture_ratio = 20;
 150         devc->stl = NULL;
 151
 152         if (num_logic_channels > 0) {
 153                 /* Logic channels, all in one channel group. */
 154                 cg = g_malloc0(sizeof(struct sr_channel_group));
 155                 cg->name = g_strdup("Logic");
 156                 for (i = 0; i < num_logic_channels; i++) {
 157                         sprintf(channel_name, "D%d", i);
 158                         ch = sr_channel_new(sdi, i, SR_CHANNEL_LOGIC, TRUE, channel_name);
 159                         cg->channels = g_slist_append(cg->channels, ch);
 160                 }
 161                 sdi->channel_groups = g_slist_append(NULL, cg);
 162         }
 163
 164         /* Analog channels, channel groups and pattern generators. */
 165         devc->ch_ag = g_hash_table_new(g_direct_hash, g_direct_equal);
 166         if (num_analog_channels > 0) {
 167                 /*
 168                  * Have the waveform for analog patterns pre-generated. It's
 169                  * supposed to be periodic, so the generator just needs to
 170                  * access the prepared sample data (DDS style).
 171                  */
 172                 demo_generate_analog_pattern(devc);
 173
 174                 pattern = 0;
 175                 /* An "Analog" channel group with all analog channels in it. */
 176                 acg = g_malloc0(sizeof(struct sr_channel_group));
 177                 acg->name = g_strdup("Analog");
 178                 sdi->channel_groups = g_slist_append(sdi->channel_groups, acg);
 179
 180                 for (i = 0; i < num_analog_channels; i++) {
 181                         snprintf(channel_name, 16, "A%d", i);
 182                         ch = sr_channel_new(sdi, i + num_logic_channels, SR_CHANNEL_ANALOG,
 183                                         TRUE, channel_name);
 184                         acg->channels = g_slist_append(acg->channels, ch);
 185
 186                         /* Every analog channel gets its own channel group as well. */
 187                         cg = g_malloc0(sizeof(struct sr_channel_group));
 188                         cg->name = g_strdup(channel_name);
 189                         cg->channels = g_slist_append(NULL, ch);
 190                         sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
 191
 192                         /* Every channel gets a generator struct. */
 193                         ag = g_malloc(sizeof(struct analog_gen));
 194                         ag->ch = ch;
 195                         ag->mq = SR_MQ_VOLTAGE;
 196                         ag->mq_flags = SR_MQFLAG_DC;
 197                         ag->unit = SR_UNIT_VOLT;
 198                         ag->amplitude = DEFAULT_ANALOG_AMPLITUDE;
 199                         ag->offset = DEFAULT_ANALOG_OFFSET;
 200                         sr_analog_init(&ag->packet, &ag->encoding, &ag->meaning, &ag->spec, 2);
 201                         ag->packet.meaning->channels = cg->channels;
 202                         ag->packet.meaning->mq = ag->mq;
 203                         ag->packet.meaning->mqflags = ag->mq_flags;
 204                         ag->packet.meaning->unit = ag->unit;
 205                         ag->packet.encoding->digits = DEFAULT_ANALOG_ENCODING_DIGITS;
 206                         ag->packet.spec->spec_digits = DEFAULT_ANALOG_SPEC_DIGITS;
 207                         ag->packet.data = devc->analog_patterns[pattern];
 208                         ag->pattern = pattern;
 209                         ag->avg_val = 0.0f;
 210                         ag->num_avgs = 0;
 211                         g_hash_table_insert(devc->ch_ag, ch, ag);
 212
 213                         if (++pattern == ARRAY_SIZE(analog_pattern_str))
 214                                 pattern = 0;
 215                 }
 216         }
 217
 218         sdi->priv = devc;
 219
 220         return std_scan_complete(di, g_slist_append(NULL, sdi));
 221 }
 222
 223 static void clear_helper(struct dev_context *devc)
 224 {
 225         GHashTableIter iter;
 226         void *value;
 227
 228         demo_free_analog_pattern(devc);
 229
 230         /* Analog generators. */
 231         g_hash_table_iter_init(&iter, devc->ch_ag);
 232         while (g_hash_table_iter_next(&iter, NULL, &value))
 233                 g_free(value);
 234         g_hash_table_unref(devc->ch_ag);
 235 }
 236
 237 static int dev_clear(const struct sr_dev_driver *di)
 238 {
 239         return std_dev_clear_with_callback(di, (std_dev_clear_callback)clear_helper);
 240 }
 241
 242 static int config_get(uint32_t key, GVariant **data,
 243         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 244 {
 245         struct dev_context *devc;
 246         struct sr_channel *ch;
 247         struct analog_gen *ag;
 248         GVariant *mq_arr[2];
 249         int pattern;
 250
 251         if (!sdi)
 252                 return SR_ERR_ARG;
 253
 254         devc = sdi->priv;
 255         switch (key) {
 256         case SR_CONF_SAMPLERATE:
 257                 *data = g_variant_new_uint64(devc->cur_samplerate);
 258                 break;
 259         case SR_CONF_LIMIT_SAMPLES:
 260                 *data = g_variant_new_uint64(devc->limit_samples);
 261                 break;
 262         case SR_CONF_LIMIT_MSEC:
 263                 *data = g_variant_new_uint64(devc->limit_msec);
 264                 break;
 265         case SR_CONF_LIMIT_FRAMES:
 266                 *data = g_variant_new_uint64(devc->limit_frames);
 267                 break;
 268         case SR_CONF_AVERAGING:
 269                 *data = g_variant_new_boolean(devc->avg);
 270                 break;
 271         case SR_CONF_AVG_SAMPLES:
 272                 *data = g_variant_new_uint64(devc->avg_samples);
 273                 break;
 274         case SR_CONF_MEASURED_QUANTITY:
 275                 if (!cg)
 276                         return SR_ERR_CHANNEL_GROUP;
 277                 /* Any channel in the group will do. */
 278                 ch = cg->channels->data;
 279                 if (ch->type != SR_CHANNEL_ANALOG)
 280                         return SR_ERR_ARG;
 281                 ag = g_hash_table_lookup(devc->ch_ag, ch);
 282                 mq_arr[0] = g_variant_new_uint32(ag->mq);
 283                 mq_arr[1] = g_variant_new_uint64(ag->mq_flags);
 284                 *data = g_variant_new_tuple(mq_arr, 2);
 285                 break;
 286         case SR_CONF_PATTERN_MODE:
 287                 if (!cg)
 288                         return SR_ERR_CHANNEL_GROUP;
 289                 /* Any channel in the group will do. */
 290                 ch = cg->channels->data;
 291                 if (ch->type == SR_CHANNEL_LOGIC) {
 292                         pattern = devc->logic_pattern;
 293                         *data = g_variant_new_string(logic_pattern_str[pattern]);
 294                 } else if (ch->type == SR_CHANNEL_ANALOG) {
 295                         ag = g_hash_table_lookup(devc->ch_ag, ch);
 296                         pattern = ag->pattern;
 297                         *data = g_variant_new_string(analog_pattern_str[pattern]);
 298                 } else
 299                         return SR_ERR_BUG;
 300                 break;
 301         case SR_CONF_AMPLITUDE:
 302                 if (!cg)
 303                         return SR_ERR_CHANNEL_GROUP;
 304                 /* Any channel in the group will do. */
 305                 ch = cg->channels->data;
 306                 if (ch->type != SR_CHANNEL_ANALOG)
 307                         return SR_ERR_ARG;
 308                 ag = g_hash_table_lookup(devc->ch_ag, ch);
 309                 *data = g_variant_new_double(ag->amplitude);
 310                 break;
 311         case SR_CONF_OFFSET:
 312                 if (!cg)
 313                         return SR_ERR_CHANNEL_GROUP;
 314                 /* Any channel in the group will do. */
 315                 ch = cg->channels->data;
 316                 if (ch->type != SR_CHANNEL_ANALOG)
 317                         return SR_ERR_ARG;
 318                 ag = g_hash_table_lookup(devc->ch_ag, ch);
 319                 *data = g_variant_new_double(ag->offset);
 320                 break;
 321         case SR_CONF_CAPTURE_RATIO:
 322                 *data = g_variant_new_uint64(devc->capture_ratio);
 323                 break;
 324         default:
 325                 return SR_ERR_NA;
 326         }
 327
 328         return SR_OK;
 329 }
 330
 331 static int config_set(uint32_t key, GVariant *data,
 332         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 333 {
 334         struct dev_context *devc;
 335         struct analog_gen *ag;
 336         struct sr_channel *ch;
 337         GVariant *mq_tuple_child;
 338         GSList *l;
 339         int logic_pattern, analog_pattern;
 340
 341         devc = sdi->priv;
 342
 343         switch (key) {
 344         case SR_CONF_SAMPLERATE:
 345                 devc->cur_samplerate = g_variant_get_uint64(data);
 346                 break;
 347         case SR_CONF_LIMIT_SAMPLES:
 348                 devc->limit_msec = 0;
 349                 devc->limit_samples = g_variant_get_uint64(data);
 350                 break;
 351         case SR_CONF_LIMIT_MSEC:
 352                 devc->limit_msec = g_variant_get_uint64(data);
 353                 devc->limit_samples = 0;
 354                 break;
 355         case SR_CONF_LIMIT_FRAMES:
 356                 devc->limit_frames = g_variant_get_uint64(data);
 357                 break;
 358         case SR_CONF_AVERAGING:
 359                 devc->avg = g_variant_get_boolean(data);
 360                 sr_dbg("%s averaging", devc->avg ? "Enabling" : "Disabling");
 361                 break;
 362         case SR_CONF_AVG_SAMPLES:
 363                 devc->avg_samples = g_variant_get_uint64(data);
 364                 sr_dbg("Setting averaging rate to %" PRIu64, devc->avg_samples);
 365                 break;
 366         case SR_CONF_MEASURED_QUANTITY:
 367                 if (!cg)
 368                         return SR_ERR_CHANNEL_GROUP;
 369                 for (l = cg->channels; l; l = l->next) {
 370                         ch = l->data;
 371                         if (ch->type != SR_CHANNEL_ANALOG)
 372                                 return SR_ERR_ARG;
 373                         ag = g_hash_table_lookup(devc->ch_ag, ch);
 374                         mq_tuple_child = g_variant_get_child_value(data, 0);
 375                         ag->mq = g_variant_get_uint32(mq_tuple_child);
 376                         mq_tuple_child = g_variant_get_child_value(data, 1);
 377                         ag->mq_flags = g_variant_get_uint64(mq_tuple_child);
 378                         g_variant_unref(mq_tuple_child);
 379                 }
 380                 break;
 381         case SR_CONF_PATTERN_MODE:
 382                 if (!cg)
 383                         return SR_ERR_CHANNEL_GROUP;
 384                 logic_pattern = std_str_idx(data, ARRAY_AND_SIZE(logic_pattern_str));
 385                 analog_pattern = std_str_idx(data, ARRAY_AND_SIZE(analog_pattern_str));
 386                 if (logic_pattern < 0 && analog_pattern < 0)
 387                         return SR_ERR_ARG;
 388                 for (l = cg->channels; l; l = l->next) {
 389                         ch = l->data;
 390                         if (ch->type == SR_CHANNEL_LOGIC) {
 391                                 if (logic_pattern == -1)
 392                                         return SR_ERR_ARG;
 393                                 sr_dbg("Setting logic pattern to %s",
 394                                                 logic_pattern_str[logic_pattern]);
 395                                 devc->logic_pattern = logic_pattern;
 396                                 /* Might as well do this now, these are static. */
 397                                 if (logic_pattern == PATTERN_ALL_LOW)
 398                                         memset(devc->logic_data, 0x00, LOGIC_BUFSIZE);
 399                                 else if (logic_pattern == PATTERN_ALL_HIGH)
 400                                         memset(devc->logic_data, 0xff, LOGIC_BUFSIZE);
 401                         } else if (ch->type == SR_CHANNEL_ANALOG) {
 402                                 if (analog_pattern == -1)
 403                                         return SR_ERR_ARG;
 404                                 sr_dbg("Setting analog pattern for channel %s to %s",
 405                                                 ch->name, analog_pattern_str[analog_pattern]);
 406                                 ag = g_hash_table_lookup(devc->ch_ag, ch);
 407                                 ag->pattern = analog_pattern;
 408                         } else
 409                                 return SR_ERR_BUG;
 410                 }
 411                 break;
 412         case SR_CONF_AMPLITUDE:
 413                 if (!cg)
 414                         return SR_ERR_CHANNEL_GROUP;
 415                 for (l = cg->channels; l; l = l->next) {
 416                         ch = l->data;
 417                         if (ch->type != SR_CHANNEL_ANALOG)
 418                                 return SR_ERR_ARG;
 419                         ag = g_hash_table_lookup(devc->ch_ag, ch);
 420                         ag->amplitude = g_variant_get_double(data);
 421                 }
 422                 break;
 423         case SR_CONF_OFFSET:
 424                 if (!cg)
 425                         return SR_ERR_CHANNEL_GROUP;
 426                 for (l = cg->channels; l; l = l->next) {
 427                         ch = l->data;
 428                         if (ch->type != SR_CHANNEL_ANALOG)
 429                                 return SR_ERR_ARG;
 430                         ag = g_hash_table_lookup(devc->ch_ag, ch);
 431                         ag->offset = g_variant_get_double(data);
 432                 }
 433                 break;
 434         case SR_CONF_CAPTURE_RATIO:
 435                 devc->capture_ratio = g_variant_get_uint64(data);
 436                 break;
 437         default:
 438                 return SR_ERR_NA;
 439         }
 440
 441         return SR_OK;
 442 }
 443
 444 static int config_list(uint32_t key, GVariant **data,
 445         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 446 {
 447         struct sr_channel *ch;
 448
 449         if (!cg) {
 450                 switch (key) {
 451                 case SR_CONF_SCAN_OPTIONS:
 452                 case SR_CONF_DEVICE_OPTIONS:
 453                         return STD_CONFIG_LIST(key, data, sdi, cg, scanopts, drvopts, devopts);
 454                 case SR_CONF_SAMPLERATE:
 455                         *data = std_gvar_samplerates_steps(ARRAY_AND_SIZE(samplerates));
 456                         break;
 457                 case SR_CONF_TRIGGER_MATCH:
 458                         *data = std_gvar_array_i32(ARRAY_AND_SIZE(trigger_matches));
 459                         break;
 460                 default:
 461                         return SR_ERR_NA;
 462                 }
 463         } else {
 464                 ch = cg->channels->data;
 465                 switch (key) {
 466                 case SR_CONF_DEVICE_OPTIONS:
 467                         if (ch->type == SR_CHANNEL_LOGIC)
 468                                 *data = std_gvar_array_u32(ARRAY_AND_SIZE(devopts_cg_logic));
 469                         else if (ch->type == SR_CHANNEL_ANALOG) {
 470                                 if (strcmp(cg->name, "Analog") == 0)
 471                                         *data = std_gvar_array_u32(ARRAY_AND_SIZE(devopts_cg_analog_group));
 472                                 else
 473                                         *data = std_gvar_array_u32(ARRAY_AND_SIZE(devopts_cg_analog_channel));
 474                         }
 475                         else
 476                                 return SR_ERR_BUG;
 477                         break;
 478                 case SR_CONF_PATTERN_MODE:
 479                         /* The analog group (with all 4 channels) shall not have a pattern property. */
 480                         if (strcmp(cg->name, "Analog") == 0)
 481                                 return SR_ERR_NA;
 482
 483                         if (ch->type == SR_CHANNEL_LOGIC)
 484                                 *data = g_variant_new_strv(ARRAY_AND_SIZE(logic_pattern_str));
 485                         else if (ch->type == SR_CHANNEL_ANALOG)
 486                                 *data = g_variant_new_strv(ARRAY_AND_SIZE(analog_pattern_str));
 487                         else
 488                                 return SR_ERR_BUG;
 489                         break;
 490                 default:
 491                         return SR_ERR_NA;
 492                 }
 493         }
 494
 495         return SR_OK;
 496 }
 497
 498 static int dev_acquisition_start(const struct sr_dev_inst *sdi)
 499 {
 500         struct dev_context *devc;
 501         GSList *l;
 502         struct sr_channel *ch;
 503         int bitpos;
 504         uint8_t mask;
 505         struct sr_trigger *trigger;
 506
 507         devc = sdi->priv;
 508         devc->sent_samples = 0;
 509         devc->sent_frame_samples = 0;
 510
 511         /* Setup triggers */
 512         if ((trigger = sr_session_trigger_get(sdi->session))) {
 513                 int pre_trigger_samples = 0;
 514                 if (devc->limit_samples > 0)
 515                         pre_trigger_samples = (devc->capture_ratio * devc->limit_samples) / 100;
 516                 devc->stl = soft_trigger_logic_new(sdi, trigger, pre_trigger_samples);
 517                 if (!devc->stl)
 518                         return SR_ERR_MALLOC;
 519
 520                 /* Disable all analog channels since using them when there are logic
 521                  * triggers set up would require having pre-trigger sample buffers
 522                  * for analog sample data.
 523                  */
 524                 for (l = sdi->channels; l; l = l->next) {
 525                         ch = l->data;
 526                         if (ch->type == SR_CHANNEL_ANALOG)
 527                                 ch->enabled = FALSE;
 528                 }
 529         }
 530         devc->trigger_fired = FALSE;
 531
 532         /*
 533          * Determine the numbers of logic and analog channels that are
 534          * involved in the acquisition. Determine an offset and a mask to
 535          * remove excess logic data content before datafeed submission.
 536          */
 537         devc->enabled_logic_channels = 0;
 538         devc->enabled_analog_channels = 0;
 539         for (l = sdi->channels; l; l = l->next) {
 540                 ch = l->data;
 541                 if (!ch->enabled)
 542                         continue;
 543                 if (ch->type == SR_CHANNEL_ANALOG) {
 544                         devc->enabled_analog_channels++;
 545                         continue;
 546                 }
 547                 if (ch->type != SR_CHANNEL_LOGIC)
 548                         continue;
 549                 /*
 550                  * TODO: Need we create a channel map here, such that the
 551                  * session datafeed packets will have a dense representation
 552                  * of the enabled channels' data? For example store channels
 553                  * D3 and D5 in bit positions 0 and 1 respectively, when all
 554                  * other channels are disabled? The current implementation
 555                  * generates a sparse layout, might provide data for logic
 556                  * channels that are disabled while it might suppress data
 557                  * from enabled channels at the same time.
 558                  */
 559                 devc->enabled_logic_channels++;
 560         }
 561         devc->first_partial_logic_index = devc->enabled_logic_channels / 8;
 562         bitpos = devc->enabled_logic_channels % 8;
 563         mask = (1 << bitpos) - 1;
 564         devc->first_partial_logic_mask = mask;
 565         sr_dbg("num logic %zu, partial off %zu, mask 0x%02x.",
 566                 devc->enabled_logic_channels,
 567                 devc->first_partial_logic_index,
 568                 devc->first_partial_logic_mask);
 569
 570         sr_session_source_add(sdi->session, -1, 0, 100,
 571                         demo_prepare_data, (struct sr_dev_inst *)sdi);
 572
 573         std_session_send_df_header(sdi);
 574
 575         if (devc->limit_frames > 0)
 576                 std_session_send_df_frame_begin(sdi);
 577
 578         /* We use this timestamp to decide how many more samples to send. */
 579         devc->start_us = g_get_monotonic_time();
 580         devc->spent_us = 0;
 581         devc->step = 0;
 582
 583         return SR_OK;
 584 }
 585
 586 static int dev_acquisition_stop(struct sr_dev_inst *sdi)
 587 {
 588         struct dev_context *devc;
 589
 590         sr_session_source_remove(sdi->session, -1);
 591
 592         devc = sdi->priv;
 593         if (devc->limit_frames > 0)
 594                 std_session_send_df_frame_end(sdi);
 595
 596         std_session_send_df_end(sdi);
 597
 598         if (devc->stl) {
 599                 soft_trigger_logic_free(devc->stl);
 600                 devc->stl = NULL;
 601         }
 602
 603         return SR_OK;
 604 }
 605
 606 static struct sr_dev_driver demo_driver_info = {
 607         .name = "demo",
 608         .longname = "Demo driver and pattern generator",
 609         .api_version = 1,
 610         .init = std_init,
 611         .cleanup = std_cleanup,
 612         .scan = scan,
 613         .dev_list = std_dev_list,
 614         .dev_clear = dev_clear,
 615         .config_get = config_get,
 616         .config_set = config_set,
 617         .config_list = config_list,
 618         .dev_open = std_dummy_dev_open,
 619         .dev_close = std_dummy_dev_close,
 620         .dev_acquisition_start = dev_acquisition_start,
 621         .dev_acquisition_stop = dev_acquisition_stop,
 622         .context = NULL,
 623 };
 624 SR_REGISTER_DEV_DRIVER(demo_driver_info);