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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 (!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         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         sdi->status = SR_ST_ACTIVE;
259
260         devc = sdi->priv;
261         scpi_cmd(sdi, devc->device->commands, SCPI_CMD_REMOTE);
262         devc->beeper_was_set = FALSE;
263         if (scpi_cmd_resp(sdi, devc->device->commands, &beeper,
264                         G_VARIANT_TYPE_BOOLEAN, SCPI_CMD_BEEPER) == SR_OK) {
265                 if (g_variant_get_boolean(beeper)) {
266                         devc->beeper_was_set = TRUE;
267                         scpi_cmd(sdi, devc->device->commands, SCPI_CMD_BEEPER_DISABLE);
268                 }
269                 g_variant_unref(beeper);
270         }
271
272         return SR_OK;
273 }
274
275 static int dev_close(struct sr_dev_inst *sdi)
276 {
277         struct sr_scpi_dev_inst *scpi;
278         struct dev_context *devc;
279
280         devc = sdi->priv;
281         scpi = sdi->conn;
282         if (scpi) {
283                 if (devc->beeper_was_set)
284                         scpi_cmd(sdi, devc->device->commands, SCPI_CMD_BEEPER_ENABLE);
285                 scpi_cmd(sdi, devc->device->commands, SCPI_CMD_LOCAL);
286                 sr_scpi_close(scpi);
287                 sdi->status = SR_ST_INACTIVE;
288         }
289
290         return SR_OK;
291 }
292
293 static void clear_helper(void *priv)
294 {
295         struct dev_context *devc;
296
297         devc = priv;
298         g_free(devc->channels);
299         g_free(devc->channel_groups);
300         g_free(devc);
301 }
302
303 static int dev_clear(const struct sr_dev_driver *di)
304 {
305         return std_dev_clear(di, clear_helper);
306 }
307
308 static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
309                 const struct sr_channel_group *cg)
310 {
311         struct dev_context *devc;
312         const GVariantType *gvtype;
313         unsigned int i;
314         int cmd, ret;
315         const char *s;
316
317         if (!sdi)
318                 return SR_ERR_ARG;
319
320         devc = sdi->priv;
321
322         if (cg) {
323                 /*
324                  * These options only apply to channel groups with a single
325                  * channel -- they're per-channel settings for the device.
326                  */
327
328                 /*
329                  * Config keys are handled below depending on whether a channel
330                  * group was provided by the frontend. However some of these
331                  * take a CG on one PPS but not on others. Check the device's
332                  * profile for that here, and NULL out the channel group as needed.
333                  */
334                 for (i = 0; i < devc->device->num_devopts; i++) {
335                         if (devc->device->devopts[i] == key) {
336                                 cg = NULL;
337                                 break;
338                         }
339                 }
340         }
341
342         gvtype = NULL;
343         cmd = -1;
344         switch (key) {
345         case SR_CONF_ENABLED:
346                 gvtype = G_VARIANT_TYPE_BOOLEAN;
347                 cmd = SCPI_CMD_GET_OUTPUT_ENABLED;
348                 break;
349         case SR_CONF_VOLTAGE:
350                 gvtype = G_VARIANT_TYPE_DOUBLE;
351                 cmd = SCPI_CMD_GET_MEAS_VOLTAGE;
352                 break;
353         case SR_CONF_VOLTAGE_TARGET:
354                 gvtype = G_VARIANT_TYPE_DOUBLE;
355                 cmd = SCPI_CMD_GET_VOLTAGE_TARGET;
356                 break;
357         case SR_CONF_OUTPUT_FREQUENCY:
358                 gvtype = G_VARIANT_TYPE_DOUBLE;
359                 cmd = SCPI_CMD_GET_MEAS_FREQUENCY;
360                 break;
361         case SR_CONF_OUTPUT_FREQUENCY_TARGET:
362                 gvtype = G_VARIANT_TYPE_DOUBLE;
363                 cmd = SCPI_CMD_GET_FREQUENCY_TARGET;
364                 break;
365         case SR_CONF_CURRENT:
366                 gvtype = G_VARIANT_TYPE_DOUBLE;
367                 cmd = SCPI_CMD_GET_MEAS_CURRENT;
368                 break;
369         case SR_CONF_CURRENT_LIMIT:
370                 gvtype = G_VARIANT_TYPE_DOUBLE;
371                 cmd = SCPI_CMD_GET_CURRENT_LIMIT;
372                 break;
373         case SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED:
374                 gvtype = G_VARIANT_TYPE_BOOLEAN;
375                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ENABLED;
376                 break;
377         case SR_CONF_OVER_VOLTAGE_PROTECTION_ACTIVE:
378                 gvtype = G_VARIANT_TYPE_BOOLEAN;
379                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ACTIVE;
380                 break;
381         case SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD:
382                 gvtype = G_VARIANT_TYPE_DOUBLE;
383                 cmd = SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_THRESHOLD;
384                 break;
385         case SR_CONF_OVER_CURRENT_PROTECTION_ENABLED:
386                 gvtype = G_VARIANT_TYPE_BOOLEAN;
387                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ENABLED;
388                 break;
389         case SR_CONF_OVER_CURRENT_PROTECTION_ACTIVE:
390                 gvtype = G_VARIANT_TYPE_BOOLEAN;
391                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ACTIVE;
392                 break;
393         case SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD:
394                 gvtype = G_VARIANT_TYPE_DOUBLE;
395                 cmd = SCPI_CMD_GET_OVER_CURRENT_PROTECTION_THRESHOLD;
396                 break;
397         case SR_CONF_OVER_TEMPERATURE_PROTECTION:
398                 gvtype = G_VARIANT_TYPE_BOOLEAN;
399                 cmd = SCPI_CMD_GET_OVER_TEMPERATURE_PROTECTION;
400                 break;
401         case SR_CONF_REGULATION:
402                 gvtype = G_VARIANT_TYPE_STRING;
403                 cmd = SCPI_CMD_GET_OUTPUT_REGULATION;
404         }
405         if (!gvtype)
406                 return SR_ERR_NA;
407
408         if (cg)
409                 select_channel(sdi, cg->channels->data);
410         ret = scpi_cmd_resp(sdi, devc->device->commands, data, gvtype, cmd);
411
412         if (cmd == SCPI_CMD_GET_OUTPUT_REGULATION) {
413                 /*
414                  * The Rigol DP800 series return CV/CC/UR, Philips PM2800
415                  * return VOLT/CURR. We always return a GVariant string in
416                  * the Rigol notation.
417                  */
418                 s = g_variant_get_string(*data, NULL);
419                 if (!strcmp(s, "VOLT")) {
420                         g_variant_unref(*data);
421                         *data = g_variant_new_string("CV");
422                 } else if (!strcmp(s, "CURR")) {
423                         g_variant_unref(*data);
424                         *data = g_variant_new_string("CC");
425                 }
426
427                 s = g_variant_get_string(*data, NULL);
428                 if (strcmp(s, "CV") && strcmp(s, "CC") && strcmp(s, "UR")) {
429                         sr_dbg("Unknown response to SCPI_CMD_GET_OUTPUT_REGULATION: %s", s);
430                         ret = SR_ERR_DATA;
431                 }
432         }
433
434         return ret;
435 }
436
437 static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
438                 const struct sr_channel_group *cg)
439 {
440         struct dev_context *devc;
441         double d;
442         int ret;
443
444         if (!sdi)
445                 return SR_ERR_ARG;
446
447         if (cg)
448                 /* Channel group specified. */
449                 select_channel(sdi, cg->channels->data);
450
451         devc = sdi->priv;
452
453         switch (key) {
454         case SR_CONF_ENABLED:
455                 if (g_variant_get_boolean(data))
456                         ret = scpi_cmd(sdi, devc->device->commands,
457                                         SCPI_CMD_SET_OUTPUT_ENABLE);
458                 else
459                         ret = scpi_cmd(sdi, devc->device->commands,
460                                         SCPI_CMD_SET_OUTPUT_DISABLE);
461                 break;
462         case SR_CONF_VOLTAGE_TARGET:
463                 d = g_variant_get_double(data);
464                 ret = scpi_cmd(sdi, devc->device->commands,
465                                 SCPI_CMD_SET_VOLTAGE_TARGET, d);
466                 break;
467         case SR_CONF_OUTPUT_FREQUENCY_TARGET:
468                 d = g_variant_get_double(data);
469                 ret = scpi_cmd(sdi, devc->device->commands,
470                                 SCPI_CMD_SET_FREQUENCY_TARGET, d);
471                 break;
472         case SR_CONF_CURRENT_LIMIT:
473                 d = g_variant_get_double(data);
474                 ret = scpi_cmd(sdi, devc->device->commands,
475                                 SCPI_CMD_SET_CURRENT_LIMIT, d);
476                 break;
477         case SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED:
478                 if (g_variant_get_boolean(data))
479                         ret = scpi_cmd(sdi, devc->device->commands,
480                                         SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLE);
481                 else
482                         ret = scpi_cmd(sdi, devc->device->commands,
483                                         SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_DISABLE);
484                 break;
485         case SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD:
486                 d = g_variant_get_double(data);
487                 ret = scpi_cmd(sdi, devc->device->commands,
488                                 SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_THRESHOLD, d);
489                 break;
490         case SR_CONF_OVER_CURRENT_PROTECTION_ENABLED:
491                 if (g_variant_get_boolean(data))
492                         ret = scpi_cmd(sdi, devc->device->commands,
493                                         SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLE);
494                 else
495                         ret = scpi_cmd(sdi, devc->device->commands,
496                                         SCPI_CMD_SET_OVER_CURRENT_PROTECTION_DISABLE);
497                 break;
498         case SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD:
499                 d = g_variant_get_double(data);
500                 ret = scpi_cmd(sdi, devc->device->commands,
501                                 SCPI_CMD_SET_OVER_CURRENT_PROTECTION_THRESHOLD, d);
502                 break;
503         case SR_CONF_OVER_TEMPERATURE_PROTECTION:
504                 if (g_variant_get_boolean(data))
505                         ret = scpi_cmd(sdi, devc->device->commands,
506                                         SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_ENABLE);
507                 else
508                         ret = scpi_cmd(sdi, devc->device->commands,
509                                         SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_DISABLE);
510                 break;
511         default:
512                 ret = SR_ERR_NA;
513         }
514
515         return ret;
516 }
517
518 static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
519                 const struct sr_channel_group *cg)
520 {
521         struct dev_context *devc;
522         struct sr_channel *ch;
523         const struct channel_spec *ch_spec;
524         GVariant *gvar;
525         GVariantBuilder gvb;
526         int ret, i;
527         const char *s[16];
528
529         /* Always available, even without sdi. */
530         if (key == SR_CONF_SCAN_OPTIONS) {
531                 *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
532                                 scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
533                 return SR_OK;
534         } else if (key == SR_CONF_DEVICE_OPTIONS && !sdi) {
535                 *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
536                                 drvopts, ARRAY_SIZE(drvopts), sizeof(uint32_t));
537                 return SR_OK;
538         }
539
540         if (!sdi)
541                 return SR_ERR_ARG;
542         devc = sdi->priv;
543
544         ret = SR_OK;
545         if (!cg) {
546                 /* No channel group: global options. */
547                 switch (key) {
548                 case SR_CONF_DEVICE_OPTIONS:
549                         *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
550                                         devc->device->devopts, devc->device->num_devopts,
551                                         sizeof(uint32_t));
552                         break;
553                 case SR_CONF_CHANNEL_CONFIG:
554                         /* Not used. */
555                         i = 0;
556                         if (devc->device->features & PPS_INDEPENDENT)
557                                 s[i++] = "Independent";
558                         if (devc->device->features & PPS_SERIES)
559                                 s[i++] = "Series";
560                         if (devc->device->features & PPS_PARALLEL)
561                                 s[i++] = "Parallel";
562                         if (i == 0) {
563                                 /*
564                                  * Shouldn't happen: independent-only devices
565                                  * shouldn't advertise this option at all.
566                                  */
567                                 return SR_ERR_NA;
568                         }
569                         *data = g_variant_new_strv(s, i);
570                         break;
571                 default:
572                         return SR_ERR_NA;
573                 }
574         } else {
575                 /* Channel group specified. */
576                 /*
577                  * Per-channel-group options depending on a channel are actually
578                  * done with the first channel. Channel groups in PPS can have
579                  * more than one channel, but they will typically be of equal
580                  * specification for use in series or parallel mode.
581                  */
582                 ch = cg->channels->data;
583
584                 switch (key) {
585                 case SR_CONF_DEVICE_OPTIONS:
586                         *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
587                                         devc->device->devopts_cg, devc->device->num_devopts_cg,
588                                         sizeof(uint32_t));
589                         break;
590                 case SR_CONF_VOLTAGE_TARGET:
591                         ch_spec = &(devc->device->channels[ch->index]);
592                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
593                         /* Min, max, write resolution. */
594                         for (i = 0; i < 3; i++) {
595                                 gvar = g_variant_new_double(ch_spec->voltage[i]);
596                                 g_variant_builder_add_value(&gvb, gvar);
597                         }
598                         *data = g_variant_builder_end(&gvb);
599                         break;
600                 case SR_CONF_OUTPUT_FREQUENCY_TARGET:
601                         ch_spec = &(devc->device->channels[ch->index]);
602                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
603                         /* Min, max, write resolution. */
604                         for (i = 0; i < 3; i++) {
605                                 gvar = g_variant_new_double(ch_spec->frequency[i]);
606                                 g_variant_builder_add_value(&gvb, gvar);
607                         }
608                         *data = g_variant_builder_end(&gvb);
609                         break;
610                 case SR_CONF_CURRENT_LIMIT:
611                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
612                         /* Min, max, step. */
613                         for (i = 0; i < 3; i++) {
614                                 ch_spec = &(devc->device->channels[ch->index]);
615                                 gvar = g_variant_new_double(ch_spec->current[i]);
616                                 g_variant_builder_add_value(&gvb, gvar);
617                         }
618                         *data = g_variant_builder_end(&gvb);
619                         break;
620                 default:
621                         return SR_ERR_NA;
622                 }
623         }
624
625         return ret;
626 }
627
628 static int dev_acquisition_start(const struct sr_dev_inst *sdi)
629 {
630         struct dev_context *devc;
631         struct sr_scpi_dev_inst *scpi;
632         struct sr_channel *ch;
633         struct pps_channel *pch;
634         int cmd, ret;
635
636         devc = sdi->priv;
637         scpi = sdi->conn;
638
639         if ((ret = sr_scpi_source_add(sdi->session, scpi, G_IO_IN, 10,
640                         scpi_pps_receive_data, (void *)sdi)) != SR_OK)
641                 return ret;
642         std_session_send_df_header(sdi);
643
644         /* Prime the pipe with the first channel's fetch. */
645         ch = sr_next_enabled_channel(sdi, NULL);
646         pch = ch->priv;
647         if ((ret = select_channel(sdi, ch)) < 0)
648                 return ret;
649         if (pch->mq == SR_MQ_VOLTAGE)
650                 cmd = SCPI_CMD_GET_MEAS_VOLTAGE;
651         else if (pch->mq == SR_MQ_FREQUENCY)
652                 cmd = SCPI_CMD_GET_MEAS_FREQUENCY;
653         else if (pch->mq == SR_MQ_CURRENT)
654                 cmd = SCPI_CMD_GET_MEAS_CURRENT;
655         else if (pch->mq == SR_MQ_POWER)
656                 cmd = SCPI_CMD_GET_MEAS_POWER;
657         else
658                 return SR_ERR;
659         scpi_cmd(sdi, devc->device->commands, cmd, pch->hwname);
660
661         return SR_OK;
662 }
663
664 static int dev_acquisition_stop(struct sr_dev_inst *sdi)
665 {
666         struct sr_scpi_dev_inst *scpi;
667         float f;
668
669         scpi = sdi->conn;
670
671         /*
672          * A requested value is certainly on the way. Retrieve it now,
673          * to avoid leaving the device in a state where it's not expecting
674          * commands.
675          */
676         sr_scpi_get_float(scpi, NULL, &f);
677         sr_scpi_source_remove(sdi->session, scpi);
678
679         std_session_send_df_end(sdi);
680
681         return SR_OK;
682 }
683
684 static struct sr_dev_driver scpi_pps_driver_info = {
685         .name = "scpi-pps",
686         .longname = "SCPI PPS",
687         .api_version = 1,
688         .init = std_init,
689         .cleanup = std_cleanup,
690         .scan = scan_scpi_pps,
691         .dev_list = std_dev_list,
692         .dev_clear = dev_clear,
693         .config_get = config_get,
694         .config_set = config_set,
695         .config_list = config_list,
696         .dev_open = dev_open,
697         .dev_close = dev_close,
698         .dev_acquisition_start = dev_acquisition_start,
699         .dev_acquisition_stop = dev_acquisition_stop,
700         .context = NULL,
701 };
702
703 static struct sr_dev_driver hp_ib_pps_driver_info = {
704         .name = "hpib-pps",
705         .longname = "HP-IB PPS",
706         .api_version = 1,
707         .init = std_init,
708         .cleanup = std_cleanup,
709         .scan = scan_hpib_pps,
710         .dev_list = std_dev_list,
711         .dev_clear = dev_clear,
712         .config_get = config_get,
713         .config_set = config_set,
714         .config_list = config_list,
715         .dev_open = dev_open,
716         .dev_close = dev_close,
717         .dev_acquisition_start = dev_acquisition_start,
718         .dev_acquisition_stop = dev_acquisition_stop,
719         .context = NULL,
720 };
721 SR_REGISTER_DEV_DRIVER(scpi_pps_driver_info);
722 SR_REGISTER_DEV_DRIVER(hp_ib_pps_driver_info);