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 <config.h>
  21 #include <string.h>
  22 #include <strings.h>
  23 #include "scpi.h"
  24 #include "protocol.h"
  25
  26 static struct sr_dev_driver scpi_pps_driver_info;
  27 static struct sr_dev_driver hp_ib_pps_driver_info;
  28
  29 static const uint32_t scanopts[] = {
  30         SR_CONF_CONN,
  31         SR_CONF_SERIALCOMM,
  32 };
  33
  34 static const uint32_t drvopts[] = {
  35         SR_CONF_POWER_SUPPLY,
  36 };
  37
  38 static const struct pps_channel_instance pci[] = {
  39         { SR_MQ_VOLTAGE, SCPI_CMD_GET_MEAS_VOLTAGE, "V" },
  40         { SR_MQ_CURRENT, SCPI_CMD_GET_MEAS_CURRENT, "I" },
  41         { SR_MQ_POWER, SCPI_CMD_GET_MEAS_POWER, "P" },
  42         { SR_MQ_FREQUENCY, SCPI_CMD_GET_MEAS_FREQUENCY, "F" },
  43 };
  44
  45 static struct sr_dev_inst *probe_device(struct sr_scpi_dev_inst *scpi,
  46                 int (*get_hw_id)(struct sr_scpi_dev_inst *scpi,
  47                 struct sr_scpi_hw_info **scpi_response))
  48 {
  49         struct dev_context *devc;
  50         struct sr_dev_inst *sdi;
  51         struct sr_scpi_hw_info *hw_info;
  52         struct sr_channel_group *cg;
  53         struct sr_channel *ch;
  54         const struct scpi_pps *device;
  55         struct pps_channel *pch;
  56         struct channel_spec *channels;
  57         struct channel_group_spec *channel_groups, *cgs;
  58         struct pps_channel_group *pcg;
  59         GRegex *model_re;
  60         GMatchInfo *model_mi;
  61         GSList *l;
  62         uint64_t mask;
  63         unsigned int num_channels, num_channel_groups, ch_num, ch_idx, i, j;
  64         int ret;
  65         const char *vendor;
  66         char ch_name[16];
  67
  68         if (get_hw_id(scpi, &hw_info) != SR_OK) {
  69                 sr_info("Couldn't get IDN response.");
  70                 return NULL;
  71         }
  72
  73         device = NULL;
  74         for (i = 0; i < num_pps_profiles; i++) {
  75                 vendor = sr_vendor_alias(hw_info->manufacturer);
  76                 if (g_ascii_strcasecmp(vendor, pps_profiles[i].vendor))
  77                         continue;
  78                 model_re = g_regex_new(pps_profiles[i].model, 0, 0, NULL);
  79                 if (g_regex_match(model_re, hw_info->model, 0, &model_mi))
  80                         device = &pps_profiles[i];
  81                 g_match_info_unref(model_mi);
  82                 g_regex_unref(model_re);
  83                 if (device)
  84                         break;
  85         }
  86         if (!device) {
  87                 sr_scpi_hw_info_free(hw_info);
  88                 return NULL;
  89         }
  90
  91         sdi = g_malloc0(sizeof(struct sr_dev_inst));
  92         sdi->vendor = g_strdup(vendor);
  93         sdi->model = g_strdup(hw_info->model);
  94         sdi->version = g_strdup(hw_info->firmware_version);
  95         sdi->conn = scpi;
  96         sdi->driver = &scpi_pps_driver_info;
  97         sdi->inst_type = SR_INST_SCPI;
  98         sdi->serial_num = g_strdup(hw_info->serial_number);
  99
 100         devc = g_malloc0(sizeof(struct dev_context));
 101         devc->device = device;
 102         sdi->priv = devc;
 103
 104         if (device->num_channels) {
 105                 /* Static channels and groups. */
 106                 channels = (struct channel_spec *)device->channels;
 107                 num_channels = device->num_channels;
 108                 channel_groups = (struct channel_group_spec *)device->channel_groups;
 109                 num_channel_groups = device->num_channel_groups;
 110         } else {
 111                 /* Channels and groups need to be probed. */
 112                 ret = device->probe_channels(sdi, hw_info, &channels, &num_channels,
 113                                 &channel_groups, &num_channel_groups);
 114                 if (ret != SR_OK) {
 115                         sr_err("Failed to probe for channels.");
 116                         return NULL;
 117                 }
 118                 /*
 119                  * Since these were dynamically allocated, we'll need to free them
 120                  * later.
 121                  */
 122                 devc->channels = channels;
 123                 devc->channel_groups = channel_groups;
 124         }
 125
 126         ch_idx = 0;
 127         for (ch_num = 0; ch_num < num_channels; ch_num++) {
 128                 /* Create one channel per measurable output unit. */
 129                 for (i = 0; i < ARRAY_SIZE(pci); i++) {
 130                         if (!sr_scpi_cmd_get(devc->device->commands, pci[i].command))
 131                                 continue;
 132                         g_snprintf(ch_name, 16, "%s%s", pci[i].prefix,
 133                                         channels[ch_num].name);
 134                         ch = sr_channel_new(sdi, ch_idx++, SR_CHANNEL_ANALOG, TRUE,
 135                                         ch_name);
 136                         pch = g_malloc0(sizeof(struct pps_channel));
 137                         pch->hw_output_idx = ch_num;
 138                         pch->hwname = channels[ch_num].name;
 139                         pch->mq = pci[i].mq;
 140                         ch->priv = pch;
 141                 }
 142         }
 143
 144         for (i = 0; i < num_channel_groups; i++) {
 145                 cgs = &channel_groups[i];
 146                 cg = g_malloc0(sizeof(struct sr_channel_group));
 147                 cg->name = g_strdup(cgs->name);
 148                 for (j = 0, mask = 1; j < 64; j++, mask <<= 1) {
 149                         if (cgs->channel_index_mask & mask) {
 150                                 for (l = sdi->channels; l; l = l->next) {
 151                                         ch = l->data;
 152                                         pch = ch->priv;
 153                                         if (pch->hw_output_idx == j)
 154                                                 cg->channels = g_slist_append(cg->channels, ch);
 155                                 }
 156                         }
 157                 }
 158                 pcg = g_malloc0(sizeof(struct pps_channel_group));
 159                 pcg->features = cgs->features;
 160                 cg->priv = pcg;
 161                 sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
 162         }
 163
 164         sr_scpi_hw_info_free(hw_info);
 165         hw_info = NULL;
 166
 167         sr_scpi_cmd(sdi, devc->device->commands, SCPI_CMD_LOCAL);
 168
 169         return sdi;
 170 }
 171
 172 static gchar *hpib_get_revision(struct sr_scpi_dev_inst *scpi)
 173 {
 174         int ret;
 175         gboolean matches;
 176         char *response;
 177         GRegex *version_regex;
 178
 179         ret = sr_scpi_get_string(scpi, "ROM?", &response);
 180         if (ret != SR_OK && !response)
 181                 return NULL;
 182
 183         /* Example version string: "B01 B01" */
 184         version_regex = g_regex_new("[A-Z][0-9]{2} [A-Z][0-9]{2}", 0, 0, NULL);
 185         matches = g_regex_match(version_regex, response, 0, NULL);
 186         g_regex_unref(version_regex);
 187
 188         if (!matches) {
 189                 /* Not a valid version string. Ignore it. */
 190                 g_free(response);
 191                 response = NULL;
 192         } else {
 193                 /* Replace space with dot. */
 194                 response[3] = '.';
 195         }
 196
 197         return response;
 198 }
 199
 200 /*
 201  * This function assumes the response is in the form "HP<model_number>"
 202  *
 203  * HP made many GPIB (then called HP-IB) instruments before the SCPI command
 204  * set was introduced into the standard. We haven't seen any non-HP instruments
 205  * which respond to the "ID?" query, so assume all are HP for now.
 206  */
 207 static int hpib_get_hw_id(struct sr_scpi_dev_inst *scpi,
 208                           struct sr_scpi_hw_info **scpi_response)
 209 {
 210         int ret;
 211         char *response;
 212         struct sr_scpi_hw_info *hw_info;
 213
 214         ret = sr_scpi_get_string(scpi, "ID?", &response);
 215         if ((ret != SR_OK) || !response)
 216                 return SR_ERR;
 217
 218         hw_info = g_malloc0(sizeof(struct sr_scpi_hw_info));
 219
 220         *scpi_response = hw_info;
 221         hw_info->model = response;
 222         hw_info->firmware_version = hpib_get_revision(scpi);
 223         hw_info->manufacturer = g_strdup("HP");
 224
 225         return SR_OK;
 226 }
 227
 228 static struct sr_dev_inst *probe_scpi_pps_device(struct sr_scpi_dev_inst *scpi)
 229 {
 230         return probe_device(scpi, sr_scpi_get_hw_id);
 231 }
 232
 233 static struct sr_dev_inst *probe_hpib_pps_device(struct sr_scpi_dev_inst *scpi)
 234 {
 235         return probe_device(scpi, hpib_get_hw_id);
 236 }
 237
 238 static GSList *scan_scpi_pps(struct sr_dev_driver *di, GSList *options)
 239 {
 240         return sr_scpi_scan(di->context, options, probe_scpi_pps_device);
 241 }
 242
 243 static GSList *scan_hpib_pps(struct sr_dev_driver *di, GSList *options)
 244 {
 245         return sr_scpi_scan(di->context, options, probe_hpib_pps_device);
 246 }
 247
 248 static int dev_open(struct sr_dev_inst *sdi)
 249 {
 250         struct dev_context *devc;
 251         struct sr_scpi_dev_inst *scpi;
 252         GVariant *beeper;
 253
 254         scpi = sdi->conn;
 255         if (sr_scpi_open(scpi) < 0)
 256                 return SR_ERR;
 257
 258         devc = sdi->priv;
 259         sr_scpi_cmd(sdi, devc->device->commands, SCPI_CMD_REMOTE);
 260         devc->beeper_was_set = FALSE;
 261         if (sr_scpi_cmd_resp(sdi, devc->device->commands, &beeper,
 262                         G_VARIANT_TYPE_BOOLEAN, SCPI_CMD_BEEPER) == SR_OK) {
 263                 if (g_variant_get_boolean(beeper)) {
 264                         devc->beeper_was_set = TRUE;
 265                         sr_scpi_cmd(sdi, devc->device->commands, SCPI_CMD_BEEPER_DISABLE);
 266                 }
 267                 g_variant_unref(beeper);
 268         }
 269
 270         return SR_OK;
 271 }
 272
 273 static int dev_close(struct sr_dev_inst *sdi)
 274 {
 275         struct sr_scpi_dev_inst *scpi;
 276         struct dev_context *devc;
 277
 278         devc = sdi->priv;
 279         scpi = sdi->conn;
 280
 281         if (!scpi)
 282                 return SR_ERR_BUG;
 283
 284         if (devc->beeper_was_set)
 285                 sr_scpi_cmd(sdi, devc->device->commands, SCPI_CMD_BEEPER_ENABLE);
 286         sr_scpi_cmd(sdi, devc->device->commands, SCPI_CMD_LOCAL);
 287
 288         return sr_scpi_close(scpi);
 289 }
 290
 291 static void clear_helper(struct dev_context *devc)
 292 {
 293         g_free(devc->channels);
 294         g_free(devc->channel_groups);
 295 }
 296
 297 static int dev_clear(const struct sr_dev_driver *di)
 298 {
 299         return std_dev_clear_with_callback(di, (std_dev_clear_callback)clear_helper);
 300 }
 301
 302 static int config_get(uint32_t key, GVariant **data,
 303         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 304 {
 305         struct dev_context *devc;
 306         const GVariantType *gvtype;
 307         unsigned int i;
 308         int cmd, ret;
 309         const char *s;
 310
 311         if (!sdi)
 312                 return SR_ERR_ARG;
 313
 314         devc = sdi->priv;
 315
 316         if (cg) {
 317                 /*
 318                  * These options only apply to channel groups with a single
 319                  * channel -- they're per-channel settings for the device.
 320                  */
 321
 322                 /*
 323                  * Config keys are handled below depending on whether a channel
 324                  * group was provided by the frontend. However some of these
 325                  * take a CG on one PPS but not on others. Check the device's
 326                  * profile for that here, and NULL out the channel group as needed.
 327                  */
 328                 for (i = 0; i < devc->device->num_devopts; i++) {
 329                         if (devc->device->devopts[i] == key) {
 330                                 cg = NULL;
 331                                 break;
 332                         }
 333                 }
 334         }
 335
 336         gvtype = NULL;
 337         cmd = -1;
 338         switch (key) {
 339         case SR_CONF_ENABLED:
 340                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 341                 cmd = SCPI_CMD_GET_OUTPUT_ENABLED;
 342                 break;
 343         case SR_CONF_VOLTAGE:
 344                 gvtype = G_VARIANT_TYPE_DOUBLE;
 345                 cmd = SCPI_CMD_GET_MEAS_VOLTAGE;
 346                 break;
 347         case SR_CONF_VOLTAGE_TARGET:
 348                 gvtype = G_VARIANT_TYPE_DOUBLE;
 349                 cmd = SCPI_CMD_GET_VOLTAGE_TARGET;
 350                 break;
 351         case SR_CONF_OUTPUT_FREQUENCY:
 352                 gvtype = G_VARIANT_TYPE_DOUBLE;
 353                 cmd = SCPI_CMD_GET_MEAS_FREQUENCY;
 354                 break;
 355         case SR_CONF_OUTPUT_FREQUENCY_TARGET:
 356                 gvtype = G_VARIANT_TYPE_DOUBLE;
 357                 cmd = SCPI_CMD_GET_FREQUENCY_TARGET;
 358                 break;
 359         case SR_CONF_CURRENT:
 360                 gvtype = G_VARIANT_TYPE_DOUBLE;
 361                 cmd = SCPI_CMD_GET_MEAS_CURRENT;
 362                 break;
 363         case SR_CONF_CURRENT_LIMIT:
 364                 gvtype = G_VARIANT_TYPE_DOUBLE;
 365                 cmd = SCPI_CMD_GET_CURRENT_LIMIT;
 366                 break;
 367         case SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED:
 368                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 369                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ENABLED;
 370                 break;
 371         case SR_CONF_OVER_VOLTAGE_PROTECTION_ACTIVE:
 372                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 373                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ACTIVE;
 374                 break;
 375         case SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD:
 376                 gvtype = G_VARIANT_TYPE_DOUBLE;
 377                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_THRESHOLD;
 378                 break;
 379         case SR_CONF_OVER_CURRENT_PROTECTION_ENABLED:
 380                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 381                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ENABLED;
 382                 break;
 383         case SR_CONF_OVER_CURRENT_PROTECTION_ACTIVE:
 384                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 385                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ACTIVE;
 386                 break;
 387         case SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD:
 388                 gvtype = G_VARIANT_TYPE_DOUBLE;
 389                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_THRESHOLD;
 390                 break;
 391         case SR_CONF_OVER_TEMPERATURE_PROTECTION:
 392                 gvtype = G_VARIANT_TYPE_BOOLEAN;
 393                 cmd = SCPI_CMD_GET_OVER_TEMPERATURE_PROTECTION;
 394                 break;
 395         case SR_CONF_REGULATION:
 396                 gvtype = G_VARIANT_TYPE_STRING;
 397                 cmd = SCPI_CMD_GET_OUTPUT_REGULATION;
 398         }
 399         if (!gvtype)
 400                 return SR_ERR_NA;
 401
 402         if (cg)
 403                 select_channel(sdi, cg->channels->data);
 404         ret = sr_scpi_cmd_resp(sdi, devc->device->commands, data, gvtype, cmd);
 405
 406         if (cmd == SCPI_CMD_GET_OUTPUT_REGULATION) {
 407                 /*
 408                  * The Rigol DP800 series return CV/CC/UR, Philips PM2800
 409                  * return VOLT/CURR. We always return a GVariant string in
 410                  * the Rigol notation.
 411                  */
 412                 s = g_variant_get_string(*data, NULL);
 413                 if (!strcmp(s, "VOLT")) {
 414                         g_variant_unref(*data);
 415                         *data = g_variant_new_string("CV");
 416                 } else if (!strcmp(s, "CURR")) {
 417                         g_variant_unref(*data);
 418                         *data = g_variant_new_string("CC");
 419                 }
 420
 421                 s = g_variant_get_string(*data, NULL);
 422                 if (strcmp(s, "CV") && strcmp(s, "CC") && strcmp(s, "UR")) {
 423                         sr_dbg("Unknown response to SCPI_CMD_GET_OUTPUT_REGULATION: %s", s);
 424                         ret = SR_ERR_DATA;
 425                 }
 426         }
 427
 428         return ret;
 429 }
 430
 431 static int config_set(uint32_t key, GVariant *data,
 432         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 433 {
 434         struct dev_context *devc;
 435         double d;
 436
 437         if (!sdi)
 438                 return SR_ERR_ARG;
 439
 440         if (cg)
 441                 select_channel(sdi, cg->channels->data);
 442
 443         devc = sdi->priv;
 444
 445         switch (key) {
 446         case SR_CONF_ENABLED:
 447                 if (g_variant_get_boolean(data))
 448                         return sr_scpi_cmd(sdi, devc->device->commands,
 449                                         SCPI_CMD_SET_OUTPUT_ENABLE);
 450                 else
 451                         return sr_scpi_cmd(sdi, devc->device->commands,
 452                                         SCPI_CMD_SET_OUTPUT_DISABLE);
 453                 break;
 454         case SR_CONF_VOLTAGE_TARGET:
 455                 d = g_variant_get_double(data);
 456                 return sr_scpi_cmd(sdi, devc->device->commands,
 457                                 SCPI_CMD_SET_VOLTAGE_TARGET, d);
 458                 break;
 459         case SR_CONF_OUTPUT_FREQUENCY_TARGET:
 460                 d = g_variant_get_double(data);
 461                 return sr_scpi_cmd(sdi, devc->device->commands,
 462                                 SCPI_CMD_SET_FREQUENCY_TARGET, d);
 463                 break;
 464         case SR_CONF_CURRENT_LIMIT:
 465                 d = g_variant_get_double(data);
 466                 return sr_scpi_cmd(sdi, devc->device->commands,
 467                                 SCPI_CMD_SET_CURRENT_LIMIT, d);
 468                 break;
 469         case SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED:
 470                 if (g_variant_get_boolean(data))
 471                         return sr_scpi_cmd(sdi, devc->device->commands,
 472                                         SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLE);
 473                 else
 474                         return sr_scpi_cmd(sdi, devc->device->commands,
 475                                         SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_DISABLE);
 476                 break;
 477         case SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD:
 478                 d = g_variant_get_double(data);
 479                 return sr_scpi_cmd(sdi, devc->device->commands,
 480                                 SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_THRESHOLD, d);
 481                 break;
 482         case SR_CONF_OVER_CURRENT_PROTECTION_ENABLED:
 483                 if (g_variant_get_boolean(data))
 484                         return sr_scpi_cmd(sdi, devc->device->commands,
 485                                         SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLE);
 486                 else
 487                         return sr_scpi_cmd(sdi, devc->device->commands,
 488                                         SCPI_CMD_SET_OVER_CURRENT_PROTECTION_DISABLE);
 489                 break;
 490         case SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD:
 491                 d = g_variant_get_double(data);
 492                 return sr_scpi_cmd(sdi, devc->device->commands,
 493                                 SCPI_CMD_SET_OVER_CURRENT_PROTECTION_THRESHOLD, d);
 494                 break;
 495         case SR_CONF_OVER_TEMPERATURE_PROTECTION:
 496                 if (g_variant_get_boolean(data))
 497                         return sr_scpi_cmd(sdi, devc->device->commands,
 498                                         SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_ENABLE);
 499                 else
 500                         return sr_scpi_cmd(sdi, devc->device->commands,
 501                                         SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_DISABLE);
 502                 break;
 503         default:
 504                 return SR_ERR_NA;
 505         }
 506
 507         return SR_OK;
 508 }
 509
 510 static int config_list(uint32_t key, GVariant **data,
 511         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 512 {
 513         struct dev_context *devc;
 514         struct sr_channel *ch;
 515         const struct channel_spec *ch_spec;
 516         int i;
 517         const char *s[16];
 518
 519         devc = (sdi) ? sdi->priv : NULL;
 520
 521         if (!cg) {
 522                 switch (key) {
 523                 case SR_CONF_SCAN_OPTIONS:
 524                 case SR_CONF_DEVICE_OPTIONS:
 525                         return std_opts_config_list(key, data, sdi, cg,
 526                                 ARRAY_AND_SIZE(scanopts),
 527                                 ARRAY_AND_SIZE(drvopts),
 528                                 (devc && devc->device) ? devc->device->devopts : NULL,
 529                                 (devc && devc->device) ? devc->device->num_devopts : 0);
 530                         break;
 531                 case SR_CONF_CHANNEL_CONFIG:
 532                         if (!devc || !devc->device)
 533                                 return SR_ERR_ARG;
 534                         /* Not used. */
 535                         i = 0;
 536                         if (devc->device->features & PPS_INDEPENDENT)
 537                                 s[i++] = "Independent";
 538                         if (devc->device->features & PPS_SERIES)
 539                                 s[i++] = "Series";
 540                         if (devc->device->features & PPS_PARALLEL)
 541                                 s[i++] = "Parallel";
 542                         if (i == 0) {
 543                                 /*
 544                                  * Shouldn't happen: independent-only devices
 545                                  * shouldn't advertise this option at all.
 546                                  */
 547                                 return SR_ERR_NA;
 548                         }
 549                         *data = g_variant_new_strv(s, i);
 550                         break;
 551                 default:
 552                         return SR_ERR_NA;
 553                 }
 554         } else {
 555                 /*
 556                  * Per-channel-group options depending on a channel are actually
 557                  * done with the first channel. Channel groups in PPS can have
 558                  * more than one channel, but they will typically be of equal
 559                  * specification for use in series or parallel mode.
 560                  */
 561                 ch = cg->channels->data;
 562                 if (!devc || !devc->device)
 563                         return SR_ERR_ARG;
 564                 ch_spec = &(devc->device->channels[ch->index]);
 565
 566                 switch (key) {
 567                 case SR_CONF_DEVICE_OPTIONS:
 568                         *data = std_gvar_array_u32(devc->device->devopts_cg, devc->device->num_devopts_cg);
 569                         break;
 570                 case SR_CONF_VOLTAGE_TARGET:
 571                         *data = std_gvar_min_max_step_array(ch_spec->voltage);
 572                         break;
 573                 case SR_CONF_OUTPUT_FREQUENCY_TARGET:
 574                         *data = std_gvar_min_max_step_array(ch_spec->frequency);
 575                         break;
 576                 case SR_CONF_CURRENT_LIMIT:
 577                         *data = std_gvar_min_max_step_array(ch_spec->current);
 578                         break;
 579                 default:
 580                         return SR_ERR_NA;
 581                 }
 582         }
 583
 584         return SR_OK;
 585 }
 586
 587 static int dev_acquisition_start(const struct sr_dev_inst *sdi)
 588 {
 589         struct dev_context *devc;
 590         struct sr_scpi_dev_inst *scpi;
 591         struct sr_channel *ch;
 592         struct pps_channel *pch;
 593         int ret;
 594
 595         devc = sdi->priv;
 596         scpi = sdi->conn;
 597
 598         if ((ret = sr_scpi_source_add(sdi->session, scpi, G_IO_IN, 10,
 599                         scpi_pps_receive_data, (void *)sdi)) != SR_OK)
 600                 return ret;
 601         std_session_send_df_header(sdi);
 602
 603         /* Prime the pipe with the first channel's fetch. */
 604         ch = sr_next_enabled_channel(sdi, NULL);
 605         pch = ch->priv;
 606         if ((ret = select_channel(sdi, ch)) < 0)
 607                 return ret;
 608
 609         return SR_OK;
 610 }
 611
 612 static int dev_acquisition_stop(struct sr_dev_inst *sdi)
 613 {
 614         struct sr_scpi_dev_inst *scpi;
 615         double d;
 616
 617         scpi = sdi->conn;
 618
 619         /*
 620          * A requested value is certainly on the way. Retrieve it now,
 621          * to avoid leaving the device in a state where it's not expecting
 622          * commands.
 623          *
 624          * TODO: Doesn't work for (at least) the HP 66XXB models.
 625          */
 626         sr_scpi_get_double(scpi, NULL, &d);
 627         sr_scpi_source_remove(sdi->session, scpi);
 628
 629         std_session_send_df_end(sdi);
 630
 631         return SR_OK;
 632 }
 633
 634 static struct sr_dev_driver scpi_pps_driver_info = {
 635         .name = "scpi-pps",
 636         .longname = "SCPI PPS",
 637         .api_version = 1,
 638         .init = std_init,
 639         .cleanup = std_cleanup,
 640         .scan = scan_scpi_pps,
 641         .dev_list = std_dev_list,
 642         .dev_clear = dev_clear,
 643         .config_get = config_get,
 644         .config_set = config_set,
 645         .config_list = config_list,
 646         .dev_open = dev_open,
 647         .dev_close = dev_close,
 648         .dev_acquisition_start = dev_acquisition_start,
 649         .dev_acquisition_stop = dev_acquisition_stop,
 650         .context = NULL,
 651 };
 652
 653 static struct sr_dev_driver hp_ib_pps_driver_info = {
 654         .name = "hpib-pps",
 655         .longname = "HP-IB PPS",
 656         .api_version = 1,
 657         .init = std_init,
 658         .cleanup = std_cleanup,
 659         .scan = scan_hpib_pps,
 660         .dev_list = std_dev_list,
 661         .dev_clear = dev_clear,
 662         .config_get = config_get,
 663         .config_set = config_set,
 664         .config_list = config_list,
 665         .dev_open = dev_open,
 666         .dev_close = dev_close,
 667         .dev_acquisition_start = dev_acquisition_start,
 668         .dev_acquisition_stop = dev_acquisition_stop,
 669         .context = NULL,
 670 };
 671 SR_REGISTER_DEV_DRIVER(scpi_pps_driver_info);
 672 SR_REGISTER_DEV_DRIVER(hp_ib_pps_driver_info);