src/hardware/scpi-pps/api.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2014 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 <string.h>
  21 #include <strings.h>
  22 #include "scpi.h"
  23 #include "protocol.h"
  24
  25 SR_PRIV struct sr_dev_driver scpi_pps_driver_info;
  26
  27 static const uint32_t scanopts[] = {
  28         SR_CONF_CONN,
  29         SR_CONF_SERIALCOMM,
  30 };
  31
  32 static const uint32_t drvopts[] = {
  33         SR_CONF_POWER_SUPPLY,
  34 };
  35
  36 static const struct pps_channel_instance pci[] = {
  37         { SR_MQ_VOLTAGE, SCPI_CMD_GET_MEAS_VOLTAGE, "V" },
  38         { SR_MQ_CURRENT, SCPI_CMD_GET_MEAS_CURRENT, "I" },
  39         { SR_MQ_POWER, SCPI_CMD_GET_MEAS_POWER, "P" },
  40         { SR_MQ_FREQUENCY, SCPI_CMD_GET_MEAS_FREQUENCY, "F" },
  41 };
  42
  43 static int init(struct sr_dev_driver *di, struct sr_context *sr_ctx)
  44 {
  45         return std_init(sr_ctx, di, LOG_PREFIX);
  46 }
  47
  48 static struct sr_dev_inst *probe_device(struct sr_scpi_dev_inst *scpi)
  49 {
  50         struct dev_context *devc;
  51         struct sr_dev_inst *sdi;
  52         struct sr_scpi_hw_info *hw_info;
  53         struct sr_channel_group *cg;
  54         struct sr_channel *ch;
  55         const struct scpi_pps *device;
  56         struct pps_channel *pch;
  57         struct channel_spec *channels;
  58         struct channel_group_spec *channel_groups, *cgs;
  59         struct pps_channel_group *pcg;
  60         GRegex *model_re;
  61         GMatchInfo *model_mi;
  62         GSList *l;
  63         uint64_t mask;
  64         unsigned int num_channels, num_channel_groups, ch_num, ch_idx, i, j;
  65         int ret;
  66         const char *vendor;
  67         char ch_name[16];
  68
  69         if (sr_scpi_get_hw_id(scpi, &hw_info) != SR_OK) {
  70                 sr_info("Couldn't get IDN response.");
  71                 return NULL;
  72         }
  73
  74         device = NULL;
  75         for (i = 0; i < num_pps_profiles; i++) {
  76                 vendor = sr_vendor_alias(hw_info->manufacturer);
  77                 if (strcasecmp(vendor, pps_profiles[i].vendor))
  78                         continue;
  79                 model_re = g_regex_new(pps_profiles[i].model, 0, 0, NULL);
  80                 if (g_regex_match(model_re, hw_info->model, 0, &model_mi))
  81                         device = &pps_profiles[i];
  82                 g_match_info_unref(model_mi);
  83                 g_regex_unref(model_re);
  84                 if (device)
  85                         break;
  86         }
  87         if (!device) {
  88                 sr_scpi_hw_info_free(hw_info);
  89                 return NULL;
  90         }
  91
  92         sdi = g_malloc0(sizeof(struct sr_dev_inst));
  93         sdi->status = SR_ST_INACTIVE;
  94         sdi->vendor = g_strdup(vendor);
  95         sdi->model = g_strdup(hw_info->model);
  96         sdi->version = g_strdup(hw_info->firmware_version);
  97         sdi->conn = scpi;
  98         sdi->driver = &scpi_pps_driver_info;
  99         sdi->inst_type = SR_INST_SCPI;
 100         sdi->serial_num = g_strdup(hw_info->serial_number);
 101
 102         devc = g_malloc0(sizeof(struct dev_context));
 103         devc->device = device;
 104         sdi->priv = devc;
 105
 106         if (device->num_channels) {
 107                 /* Static channels and groups. */
 108                 channels = (struct channel_spec *)device->channels;
 109                 num_channels = device->num_channels;
 110                 channel_groups = (struct channel_group_spec *)device->channel_groups;
 111                 num_channel_groups = device->num_channel_groups;
 112         } else {
 113                 /* Channels and groups need to be probed. */
 114                 ret = device->probe_channels(sdi, hw_info, &channels, &num_channels,
 115                                 &channel_groups, &num_channel_groups);
 116                 if (ret != SR_OK) {
 117                         sr_err("Failed to probe for channels.");
 118                         return NULL;
 119                 }
 120                 /*
 121                  * Since these were dynamically allocated, we'll need to free them
 122                  * later.
 123                  */
 124                 devc->channels = channels;
 125                 devc->channel_groups = channel_groups;
 126         }
 127
 128         ch_idx = 0;
 129         for (ch_num = 0; ch_num < num_channels; ch_num++) {
 130                 /* Create one channel per measurable output unit. */
 131                 for (i = 0; i < ARRAY_SIZE(pci); i++) {
 132                         if (!scpi_cmd_get(devc->device->commands, pci[i].command))
 133                                 continue;
 134                         g_snprintf(ch_name, 16, "%s%s", pci[i].prefix,
 135                                         channels[ch_num].name);
 136                         ch = sr_channel_new(sdi, ch_idx++, SR_CHANNEL_ANALOG, TRUE,
 137                                         ch_name);
 138                         pch = g_malloc0(sizeof(struct pps_channel));
 139                         pch->hw_output_idx = ch_num;
 140                         pch->hwname = channels[ch_num].name;
 141                         pch->mq = pci[i].mq;
 142                         ch->priv = pch;
 143                 }
 144         }
 145
 146         for (i = 0; i < num_channel_groups; i++) {
 147                 cgs = &channel_groups[i];
 148                 cg = g_malloc0(sizeof(struct sr_channel_group));
 149                 cg->name = g_strdup(cgs->name);
 150                 for (j = 0, mask = 1; j < 64; j++, mask <<= 1) {
 151                         if (cgs->channel_index_mask & mask) {
 152                                 for (l = sdi->channels; l; l = l->next) {
 153                                         ch = l->data;
 154                                         pch = ch->priv;
 155                                         if (pch->hw_output_idx == j)
 156                                                 cg->channels = g_slist_append(cg->channels, ch);
 157                                 }
 158                         }
 159                 }
 160                 pcg = g_malloc0(sizeof(struct pps_channel_group));
 161                 pcg->features = cgs->features;
 162                 cg->priv = pcg;
 163                 sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
 164         }
 165
 166         sr_scpi_hw_info_free(hw_info);
 167         hw_info = NULL;
 168
 169         scpi_cmd(sdi, devc->device->commands, SCPI_CMD_LOCAL);
 170         sr_scpi_close(scpi);
 171
 172         return sdi;
 173 }
 174
 175 static GSList *scan(struct sr_dev_driver *di, GSList *options)
 176 {
 177         return sr_scpi_scan(di->context, options, probe_device);
 178 }
 179
 180 static GSList *dev_list(const struct sr_dev_driver *di)
 181 {
 182         return ((struct drv_context *)(di->context))->instances;
 183 }
 184
 185 static int dev_clear(const struct sr_dev_driver *di)
 186 {
 187         return std_dev_clear(di, NULL);
 188 }
 189
 190 static int dev_open(struct sr_dev_inst *sdi)
 191 {
 192         struct dev_context *devc;
 193         struct sr_scpi_dev_inst *scpi;
 194         GVariant *beeper;
 195
 196         if (sdi->status != SR_ST_INACTIVE)
 197                 return SR_ERR;
 198
 199         scpi = sdi->conn;
 200         if (sr_scpi_open(scpi) < 0)
 201                 return SR_ERR;
 202
 203         sdi->status = SR_ST_ACTIVE;
 204
 205         devc = sdi->priv;
 206         scpi_cmd(sdi, devc->device->commands, SCPI_CMD_REMOTE);
 207         devc = sdi->priv;
 208         devc->beeper_was_set = FALSE;
 209         if (scpi_cmd_resp(sdi, devc->device->commands, &beeper,
 210                         G_VARIANT_TYPE_BOOLEAN, SCPI_CMD_BEEPER) == SR_OK) {
 211                 if (g_variant_get_boolean(beeper)) {
 212                         devc->beeper_was_set = TRUE;
 213                         scpi_cmd(sdi, devc->device->commands, SCPI_CMD_BEEPER_DISABLE);
 214                 }
 215                 g_variant_unref(beeper);
 216         }
 217
 218         return SR_OK;
 219 }
 220
 221 static int dev_close(struct sr_dev_inst *sdi)
 222 {
 223         struct sr_scpi_dev_inst *scpi;
 224         struct dev_context *devc;
 225
 226         if (sdi->status != SR_ST_ACTIVE)
 227                 return SR_ERR_DEV_CLOSED;
 228
 229         devc = sdi->priv;
 230         scpi = sdi->conn;
 231         if (scpi) {
 232                 if (devc->beeper_was_set)
 233                         scpi_cmd(sdi, devc->device->commands, SCPI_CMD_BEEPER_ENABLE);
 234                 scpi_cmd(sdi, devc->device->commands, SCPI_CMD_LOCAL);
 235                 sr_scpi_close(scpi);
 236                 sdi->status = SR_ST_INACTIVE;
 237         }
 238
 239         return SR_OK;
 240 }
 241
 242 static void clear_helper(void *priv)
 243 {
 244         struct dev_context *devc;
 245
 246         devc = priv;
 247         g_free(devc->channels);
 248         g_free(devc->channel_groups);
 249         g_free(devc);
 250 }
 251
 252 static int cleanup(const struct sr_dev_driver *di)
 253 {
 254         return std_dev_clear(di, clear_helper);
 255 }
 256
 257 static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 258                 const struct sr_channel_group *cg)
 259 {
 260         struct dev_context *devc;
 261         const GVariantType *gvtype;
 262         unsigned int i;
 263         int cmd, ret;
 264         char *s;
 265
 266         if (!sdi)
 267                 return SR_ERR_ARG;
 268
 269         devc = sdi->priv;
 270
 271         if (cg) {
 272                 /*
 273                  * These options only apply to channel groups with a single
 274                  * channel -- they're per-channel settings for the device.
 275                  */
 276
 277                 /*
 278                  * Config keys are handled below depending on whether a channel
 279                  * group was provided by the frontend. However some of these
 280                  * take a CG on one PPS but not on others. Check the device's
 281                  * profile for that here, and NULL out the channel group as needed.
 282                  */
 283                 for (i = 0; i < devc->device->num_devopts; i++) {
 284                         if (devc->device->devopts[i] == key) {
 285                                 cg = NULL;
 286                                 break;
 287                         }
 288                 }
 289         }
 290
 291         gvtype = NULL;
 292         cmd = -1;
 293         switch (key) {
 294         case SR_CONF_ENABLED:
 295                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 296                 cmd = SCPI_CMD_GET_OUTPUT_ENABLED;
 297                 break;
 298         case SR_CONF_VOLTAGE:
 299                 gvtype = G_VARIANT_TYPE_DOUBLE;
 300                 cmd = SCPI_CMD_GET_MEAS_VOLTAGE;
 301                 break;
 302         case SR_CONF_VOLTAGE_TARGET:
 303                 gvtype = G_VARIANT_TYPE_DOUBLE;
 304                 cmd = SCPI_CMD_GET_VOLTAGE_TARGET;
 305                 break;
 306         case SR_CONF_OUTPUT_FREQUENCY:
 307                 gvtype = G_VARIANT_TYPE_DOUBLE;
 308                 cmd = SCPI_CMD_GET_MEAS_FREQUENCY;
 309                 break;
 310         case SR_CONF_OUTPUT_FREQUENCY_TARGET:
 311                 gvtype = G_VARIANT_TYPE_DOUBLE;
 312                 cmd = SCPI_CMD_GET_FREQUENCY_TARGET;
 313                 break;
 314         case SR_CONF_CURRENT:
 315                 gvtype = G_VARIANT_TYPE_DOUBLE;
 316                 cmd = SCPI_CMD_GET_MEAS_CURRENT;
 317                 break;
 318         case SR_CONF_CURRENT_LIMIT:
 319                 gvtype = G_VARIANT_TYPE_DOUBLE;
 320                 cmd = SCPI_CMD_GET_CURRENT_LIMIT;
 321                 break;
 322         case SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED:
 323                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 324                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ENABLED;
 325                 break;
 326         case SR_CONF_OVER_VOLTAGE_PROTECTION_ACTIVE:
 327                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 328                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ACTIVE;
 329                 break;
 330         case SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD:
 331                 gvtype = G_VARIANT_TYPE_DOUBLE;
 332                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_THRESHOLD;
 333                 break;
 334         case SR_CONF_OVER_CURRENT_PROTECTION_ENABLED:
 335                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 336                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ENABLED;
 337                 break;
 338         case SR_CONF_OVER_CURRENT_PROTECTION_ACTIVE:
 339                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 340                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ACTIVE;
 341                 break;
 342         case SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD:
 343                 gvtype = G_VARIANT_TYPE_DOUBLE;
 344                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_THRESHOLD;
 345                 break;
 346         case SR_CONF_OVER_TEMPERATURE_PROTECTION:
 347                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 348                 cmd = SCPI_CMD_GET_OVER_TEMPERATURE_PROTECTION;
 349                 break;
 350         case SR_CONF_REGULATION:
 351                 gvtype = G_VARIANT_TYPE_STRING;
 352                 cmd = SCPI_CMD_GET_OUTPUT_REGULATION;
 353         }
 354         if (!gvtype)
 355                 return SR_ERR_NA;
 356
 357         if (cg)
 358                 select_channel(sdi, cg->channels->data);
 359         ret = scpi_cmd_resp(sdi, devc->device->commands, data, gvtype, cmd);
 360
 361         if (cmd == SCPI_CMD_GET_OUTPUT_REGULATION) {
 362                 /*
 363                  * The Rigol DP800 series return CV/CC/UR, Philips PM2800
 364                  * return VOLT/CURR. We always return a GVariant string in
 365                  * the Rigol notation.
 366                  */
 367                 if ((ret = sr_scpi_get_string(sdi->conn, NULL, &s)) != SR_OK)
 368                         return ret;
 369                 if (!strcmp(s, "CV") || !strcmp(s, "VOLT")) {
 370                         *data = g_variant_new_string("CV");
 371                 } else if (!strcmp(s, "CC") || !strcmp(s, "CURR")) {
 372                         *data = g_variant_new_string("CC");
 373                 } else if (!strcmp(s, "UR")) {
 374                         *data = g_variant_new_string("UR");
 375                 } else {
 376                         sr_dbg("Unknown response to SCPI_CMD_GET_OUTPUT_REGULATION: %s", s);
 377                         ret = SR_ERR_DATA;
 378                 }
 379                 g_free(s);
 380         }
 381
 382         return ret;
 383 }
 384
 385 static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 386                 const struct sr_channel_group *cg)
 387 {
 388         struct dev_context *devc;
 389         double d;
 390         int ret;
 391
 392         if (!sdi)
 393                 return SR_ERR_ARG;
 394
 395         if (sdi->status != SR_ST_ACTIVE)
 396                 return SR_ERR_DEV_CLOSED;
 397
 398         if (cg)
 399                 /* Channel group specified. */
 400                 select_channel(sdi, cg->channels->data);
 401
 402         devc = sdi->priv;
 403         ret = SR_OK;
 404         switch (key) {
 405         case SR_CONF_ENABLED:
 406                 if (g_variant_get_boolean(data))
 407                         ret = scpi_cmd(sdi, devc->device->commands,
 408                                         SCPI_CMD_SET_OUTPUT_ENABLE);
 409                 else
 410                         ret = scpi_cmd(sdi, devc->device->commands,
 411                                         SCPI_CMD_SET_OUTPUT_DISABLE);
 412                 break;
 413         case SR_CONF_VOLTAGE_TARGET:
 414                 d = g_variant_get_double(data);
 415                 ret = scpi_cmd(sdi, devc->device->commands,
 416                                 SCPI_CMD_SET_VOLTAGE_TARGET, d);
 417                 break;
 418         case SR_CONF_OUTPUT_FREQUENCY_TARGET:
 419                 d = g_variant_get_double(data);
 420                 ret = scpi_cmd(sdi, devc->device->commands,
 421                                 SCPI_CMD_SET_FREQUENCY_TARGET, d);
 422                 break;
 423         case SR_CONF_CURRENT_LIMIT:
 424                 d = g_variant_get_double(data);
 425                 ret = scpi_cmd(sdi, devc->device->commands,
 426                                 SCPI_CMD_SET_CURRENT_LIMIT, d);
 427                 break;
 428         case SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED:
 429                 if (g_variant_get_boolean(data))
 430                         ret = scpi_cmd(sdi, devc->device->commands,
 431                                         SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLE);
 432                 else
 433                         ret = scpi_cmd(sdi, devc->device->commands,
 434                                         SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_DISABLE);
 435                 break;
 436         case SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD:
 437                 d = g_variant_get_double(data);
 438                 ret = scpi_cmd(sdi, devc->device->commands,
 439                                 SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_THRESHOLD, d);
 440                 break;
 441         case SR_CONF_OVER_CURRENT_PROTECTION_ENABLED:
 442                 if (g_variant_get_boolean(data))
 443                         ret = scpi_cmd(sdi, devc->device->commands,
 444                                         SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLE);
 445                 else
 446                         ret = scpi_cmd(sdi, devc->device->commands,
 447                                         SCPI_CMD_SET_OVER_CURRENT_PROTECTION_DISABLE);
 448                 break;
 449         case SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD:
 450                 d = g_variant_get_double(data);
 451                 ret = scpi_cmd(sdi, devc->device->commands,
 452                                 SCPI_CMD_SET_OVER_CURRENT_PROTECTION_THRESHOLD, d);
 453                 break;
 454         case SR_CONF_OVER_TEMPERATURE_PROTECTION:
 455                 if (g_variant_get_boolean(data))
 456                         ret = scpi_cmd(sdi, devc->device->commands,
 457                                         SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_ENABLE);
 458                 else
 459                         ret = scpi_cmd(sdi, devc->device->commands,
 460                                         SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_DISABLE);
 461                 break;
 462         default:
 463                 ret = SR_ERR_NA;
 464         }
 465
 466         return ret;
 467 }
 468
 469 static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 470                 const struct sr_channel_group *cg)
 471 {
 472         struct dev_context *devc;
 473         struct sr_channel *ch;
 474         const struct channel_spec *ch_spec;
 475         GVariant *gvar;
 476         GVariantBuilder gvb;
 477         int ret, i;
 478         const char *s[16];
 479
 480         /* Always available, even without sdi. */
 481         if (key == SR_CONF_SCAN_OPTIONS) {
 482                 *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 483                                 scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
 484                 return SR_OK;
 485         } else if (key == SR_CONF_DEVICE_OPTIONS && !sdi) {
 486                 *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 487                                 drvopts, ARRAY_SIZE(drvopts), sizeof(uint32_t));
 488                 return SR_OK;
 489         }
 490
 491         if (!sdi)
 492                 return SR_ERR_ARG;
 493         devc = sdi->priv;
 494
 495         ret = SR_OK;
 496         if (!cg) {
 497                 /* No channel group: global options. */
 498                 switch (key) {
 499                 case SR_CONF_DEVICE_OPTIONS:
 500                         *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 501                                         devc->device->devopts, devc->device->num_devopts,
 502                                         sizeof(uint32_t));
 503                         break;
 504                 case SR_CONF_CHANNEL_CONFIG:
 505                         /* Not used. */
 506                         i = 0;
 507                         if (devc->device->features & PPS_INDEPENDENT)
 508                                 s[i++] = "Independent";
 509                         if (devc->device->features & PPS_SERIES)
 510                                 s[i++] = "Series";
 511                         if (devc->device->features & PPS_PARALLEL)
 512                                 s[i++] = "Parallel";
 513                         if (i == 0) {
 514                                 /*
 515                                  * Shouldn't happen: independent-only devices
 516                                  * shouldn't advertise this option at all.
 517                                  */
 518                                 return SR_ERR_NA;
 519                         }
 520                         *data = g_variant_new_strv(s, i);
 521                         break;
 522                 default:
 523                         return SR_ERR_NA;
 524                 }
 525         } else {
 526                 /* Channel group specified. */
 527                 /*
 528                  * Per-channel-group options depending on a channel are actually
 529                  * done with the first channel. Channel groups in PPS can have
 530                  * more than one channel, but they will typically be of equal
 531                  * specification for use in series or parallel mode.
 532                  */
 533                 ch = cg->channels->data;
 534
 535                 switch (key) {
 536                 case SR_CONF_DEVICE_OPTIONS:
 537                         *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 538                                         devc->device->devopts_cg, devc->device->num_devopts_cg,
 539                                         sizeof(uint32_t));
 540                         break;
 541                 case SR_CONF_VOLTAGE_TARGET:
 542                         ch_spec = &(devc->device->channels[ch->index]);
 543                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
 544                         /* Min, max, write resolution. */
 545                         for (i = 0; i < 3; i++) {
 546                                 gvar = g_variant_new_double(ch_spec->voltage[i]);
 547                                 g_variant_builder_add_value(&gvb, gvar);
 548                         }
 549                         *data = g_variant_builder_end(&gvb);
 550                         break;
 551                 case SR_CONF_OUTPUT_FREQUENCY_TARGET:
 552                         ch_spec = &(devc->device->channels[ch->index]);
 553                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
 554                         /* Min, max, write resolution. */
 555                         for (i = 0; i < 3; i++) {
 556                                 gvar = g_variant_new_double(ch_spec->frequency[i]);
 557                                 g_variant_builder_add_value(&gvb, gvar);
 558                         }
 559                         *data = g_variant_builder_end(&gvb);
 560                         break;
 561                 case SR_CONF_CURRENT_LIMIT:
 562                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
 563                         /* Min, max, step. */
 564                         for (i = 0; i < 3; i++) {
 565                                 ch_spec = &(devc->device->channels[ch->index]);
 566                                 gvar = g_variant_new_double(ch_spec->current[i]);
 567                                 g_variant_builder_add_value(&gvb, gvar);
 568                         }
 569                         *data = g_variant_builder_end(&gvb);
 570                         break;
 571                 default:
 572                         return SR_ERR_NA;
 573                 }
 574         }
 575
 576         return ret;
 577 }
 578
 579 static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
 580 {
 581         struct dev_context *devc;
 582         struct sr_scpi_dev_inst *scpi;
 583         struct sr_channel *ch;
 584         struct pps_channel *pch;
 585         int cmd, ret;
 586
 587         if (sdi->status != SR_ST_ACTIVE)
 588                 return SR_ERR_DEV_CLOSED;
 589
 590         devc = sdi->priv;
 591         scpi = sdi->conn;
 592         devc->cb_data = cb_data;
 593
 594         if ((ret = sr_scpi_source_add(sdi->session, scpi, G_IO_IN, 10,
 595                         scpi_pps_receive_data, (void *)sdi)) != SR_OK)
 596                 return ret;
 597         std_session_send_df_header(sdi, LOG_PREFIX);
 598
 599         /* Prime the pipe with the first channel's fetch. */
 600         ch = sr_next_enabled_channel(sdi, NULL);
 601         pch = ch->priv;
 602         if ((ret = select_channel(sdi, ch)) < 0)
 603                 return ret;
 604         if (pch->mq == SR_MQ_VOLTAGE)
 605                 cmd = SCPI_CMD_GET_MEAS_VOLTAGE;
 606         else if (pch->mq == SR_MQ_FREQUENCY)
 607                 cmd = SCPI_CMD_GET_MEAS_FREQUENCY;
 608         else if (pch->mq == SR_MQ_CURRENT)
 609                 cmd = SCPI_CMD_GET_MEAS_CURRENT;
 610         else if (pch->mq == SR_MQ_POWER)
 611                 cmd = SCPI_CMD_GET_MEAS_POWER;
 612         else
 613                 return SR_ERR;
 614         scpi_cmd(sdi, devc->device->commands, cmd, pch->hwname);
 615
 616         return SR_OK;
 617 }
 618
 619 static int dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
 620 {
 621         struct sr_datafeed_packet packet;
 622         struct sr_scpi_dev_inst *scpi;
 623         float f;
 624
 625         (void)cb_data;
 626
 627         if (sdi->status != SR_ST_ACTIVE)
 628                 return SR_ERR_DEV_CLOSED;
 629
 630         scpi = sdi->conn;
 631
 632         /*
 633          * A requested value is certainly on the way. Retrieve it now,
 634          * to avoid leaving the device in a state where it's not expecting
 635          * commands.
 636          */
 637         sr_scpi_get_float(scpi, NULL, &f);
 638         sr_scpi_source_remove(sdi->session, scpi);
 639
 640         packet.type = SR_DF_END;
 641         sr_session_send(sdi, &packet);
 642
 643         return SR_OK;
 644 }
 645
 646 SR_PRIV struct sr_dev_driver scpi_pps_driver_info = {
 647         .name = "scpi-pps",
 648         .longname = "SCPI PPS",
 649         .api_version = 1,
 650         .init = init,
 651         .cleanup = cleanup,
 652         .scan = scan,
 653         .dev_list = dev_list,
 654         .dev_clear = dev_clear,
 655         .config_get = config_get,
 656         .config_set = config_set,
 657         .config_list = config_list,
 658         .dev_open = dev_open,
 659         .dev_close = dev_close,
 660         .dev_acquisition_start = dev_acquisition_start,
 661         .dev_acquisition_stop = dev_acquisition_stop,
 662         .context = NULL,
 663 };