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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         devc = sdi->priv;
259         scpi_cmd(sdi, devc->device->commands, SCPI_CMD_REMOTE);
260         devc->beeper_was_set = FALSE;
261         if (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                         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                 scpi_cmd(sdi, devc->device->commands, SCPI_CMD_BEEPER_ENABLE);
286         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, const struct sr_dev_inst *sdi,
303                 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 = 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, const struct sr_dev_inst *sdi,
432                 const struct sr_channel_group *cg)
433 {
434         struct dev_context *devc;
435         double d;
436         int ret;
437
438         if (!sdi)
439                 return SR_ERR_ARG;
440
441         if (cg)
442                 /* Channel group specified. */
443                 select_channel(sdi, cg->channels->data);
444
445         devc = sdi->priv;
446
447         switch (key) {
448         case SR_CONF_ENABLED:
449                 if (g_variant_get_boolean(data))
450                         ret = scpi_cmd(sdi, devc->device->commands,
451                                         SCPI_CMD_SET_OUTPUT_ENABLE);
452                 else
453                         ret = scpi_cmd(sdi, devc->device->commands,
454                                         SCPI_CMD_SET_OUTPUT_DISABLE);
455                 break;
456         case SR_CONF_VOLTAGE_TARGET:
457                 d = g_variant_get_double(data);
458                 ret = scpi_cmd(sdi, devc->device->commands,
459                                 SCPI_CMD_SET_VOLTAGE_TARGET, d);
460                 break;
461         case SR_CONF_OUTPUT_FREQUENCY_TARGET:
462                 d = g_variant_get_double(data);
463                 ret = scpi_cmd(sdi, devc->device->commands,
464                                 SCPI_CMD_SET_FREQUENCY_TARGET, d);
465                 break;
466         case SR_CONF_CURRENT_LIMIT:
467                 d = g_variant_get_double(data);
468                 ret = scpi_cmd(sdi, devc->device->commands,
469                                 SCPI_CMD_SET_CURRENT_LIMIT, d);
470                 break;
471         case SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED:
472                 if (g_variant_get_boolean(data))
473                         ret = scpi_cmd(sdi, devc->device->commands,
474                                         SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLE);
475                 else
476                         ret = scpi_cmd(sdi, devc->device->commands,
477                                         SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_DISABLE);
478                 break;
479         case SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD:
480                 d = g_variant_get_double(data);
481                 ret = scpi_cmd(sdi, devc->device->commands,
482                                 SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_THRESHOLD, d);
483                 break;
484         case SR_CONF_OVER_CURRENT_PROTECTION_ENABLED:
485                 if (g_variant_get_boolean(data))
486                         ret = scpi_cmd(sdi, devc->device->commands,
487                                         SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLE);
488                 else
489                         ret = scpi_cmd(sdi, devc->device->commands,
490                                         SCPI_CMD_SET_OVER_CURRENT_PROTECTION_DISABLE);
491                 break;
492         case SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD:
493                 d = g_variant_get_double(data);
494                 ret = scpi_cmd(sdi, devc->device->commands,
495                                 SCPI_CMD_SET_OVER_CURRENT_PROTECTION_THRESHOLD, d);
496                 break;
497         case SR_CONF_OVER_TEMPERATURE_PROTECTION:
498                 if (g_variant_get_boolean(data))
499                         ret = scpi_cmd(sdi, devc->device->commands,
500                                         SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_ENABLE);
501                 else
502                         ret = scpi_cmd(sdi, devc->device->commands,
503                                         SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_DISABLE);
504                 break;
505         default:
506                 ret = SR_ERR_NA;
507         }
508
509         return ret;
510 }
511
512 static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
513                 const struct sr_channel_group *cg)
514 {
515         struct dev_context *devc;
516         struct sr_channel *ch;
517         const struct channel_spec *ch_spec;
518         GVariant *gvar;
519         GVariantBuilder gvb;
520         int i;
521         const char *s[16];
522
523         devc = (sdi) ? sdi->priv : NULL;
524
525         if (!cg) {
526                 /* No channel group: global options. */
527                 switch (key) {
528                 case SR_CONF_SCAN_OPTIONS:
529                 case SR_CONF_DEVICE_OPTIONS:
530                         return std_opts_config_list(key, data, sdi, cg,
531                                 scanopts, ARRAY_SIZE(scanopts),
532                                 drvopts, ARRAY_SIZE(drvopts),
533                                 (devc) ? devc->device->devopts : NULL,
534                                 (devc) ? devc->device->num_devopts : 0);
535                         break;
536                 case SR_CONF_CHANNEL_CONFIG:
537                         /* Not used. */
538                         i = 0;
539                         if (devc->device->features & PPS_INDEPENDENT)
540                                 s[i++] = "Independent";
541                         if (devc->device->features & PPS_SERIES)
542                                 s[i++] = "Series";
543                         if (devc->device->features & PPS_PARALLEL)
544                                 s[i++] = "Parallel";
545                         if (i == 0) {
546                                 /*
547                                  * Shouldn't happen: independent-only devices
548                                  * shouldn't advertise this option at all.
549                                  */
550                                 return SR_ERR_NA;
551                         }
552                         *data = g_variant_new_strv(s, i);
553                         break;
554                 default:
555                         return SR_ERR_NA;
556                 }
557         } else {
558                 /* Channel group specified. */
559                 /*
560                  * Per-channel-group options depending on a channel are actually
561                  * done with the first channel. Channel groups in PPS can have
562                  * more than one channel, but they will typically be of equal
563                  * specification for use in series or parallel mode.
564                  */
565                 ch = cg->channels->data;
566
567                 switch (key) {
568                 case SR_CONF_DEVICE_OPTIONS:
569                         *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
570                                         devc->device->devopts_cg, devc->device->num_devopts_cg,
571                                         sizeof(uint32_t));
572                         break;
573                 case SR_CONF_VOLTAGE_TARGET:
574                         ch_spec = &(devc->device->channels[ch->index]);
575                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
576                         /* Min, max, write resolution. */
577                         for (i = 0; i < 3; i++) {
578                                 gvar = g_variant_new_double(ch_spec->voltage[i]);
579                                 g_variant_builder_add_value(&gvb, gvar);
580                         }
581                         *data = g_variant_builder_end(&gvb);
582                         break;
583                 case SR_CONF_OUTPUT_FREQUENCY_TARGET:
584                         ch_spec = &(devc->device->channels[ch->index]);
585                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
586                         /* Min, max, write resolution. */
587                         for (i = 0; i < 3; i++) {
588                                 gvar = g_variant_new_double(ch_spec->frequency[i]);
589                                 g_variant_builder_add_value(&gvb, gvar);
590                         }
591                         *data = g_variant_builder_end(&gvb);
592                         break;
593                 case SR_CONF_CURRENT_LIMIT:
594                         g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
595                         /* Min, max, step. */
596                         for (i = 0; i < 3; i++) {
597                                 ch_spec = &(devc->device->channels[ch->index]);
598                                 gvar = g_variant_new_double(ch_spec->current[i]);
599                                 g_variant_builder_add_value(&gvb, gvar);
600                         }
601                         *data = g_variant_builder_end(&gvb);
602                         break;
603                 default:
604                         return SR_ERR_NA;
605                 }
606         }
607
608         return SR_OK;
609 }
610
611 static int dev_acquisition_start(const struct sr_dev_inst *sdi)
612 {
613         struct dev_context *devc;
614         struct sr_scpi_dev_inst *scpi;
615         struct sr_channel *ch;
616         struct pps_channel *pch;
617         int cmd, ret;
618
619         devc = sdi->priv;
620         scpi = sdi->conn;
621
622         if ((ret = sr_scpi_source_add(sdi->session, scpi, G_IO_IN, 10,
623                         scpi_pps_receive_data, (void *)sdi)) != SR_OK)
624                 return ret;
625         std_session_send_df_header(sdi);
626
627         /* Prime the pipe with the first channel's fetch. */
628         ch = sr_next_enabled_channel(sdi, NULL);
629         pch = ch->priv;
630         if ((ret = select_channel(sdi, ch)) < 0)
631                 return ret;
632         if (pch->mq == SR_MQ_VOLTAGE)
633                 cmd = SCPI_CMD_GET_MEAS_VOLTAGE;
634         else if (pch->mq == SR_MQ_FREQUENCY)
635                 cmd = SCPI_CMD_GET_MEAS_FREQUENCY;
636         else if (pch->mq == SR_MQ_CURRENT)
637                 cmd = SCPI_CMD_GET_MEAS_CURRENT;
638         else if (pch->mq == SR_MQ_POWER)
639                 cmd = SCPI_CMD_GET_MEAS_POWER;
640         else
641                 return SR_ERR;
642         scpi_cmd(sdi, devc->device->commands, cmd, pch->hwname);
643
644         return SR_OK;
645 }
646
647 static int dev_acquisition_stop(struct sr_dev_inst *sdi)
648 {
649         struct sr_scpi_dev_inst *scpi;
650         float f;
651
652         scpi = sdi->conn;
653
654         /*
655          * A requested value is certainly on the way. Retrieve it now,
656          * to avoid leaving the device in a state where it's not expecting
657          * commands.
658          */
659         sr_scpi_get_float(scpi, NULL, &f);
660         sr_scpi_source_remove(sdi->session, scpi);
661
662         std_session_send_df_end(sdi);
663
664         return SR_OK;
665 }
666
667 static struct sr_dev_driver scpi_pps_driver_info = {
668         .name = "scpi-pps",
669         .longname = "SCPI PPS",
670         .api_version = 1,
671         .init = std_init,
672         .cleanup = std_cleanup,
673         .scan = scan_scpi_pps,
674         .dev_list = std_dev_list,
675         .dev_clear = dev_clear,
676         .config_get = config_get,
677         .config_set = config_set,
678         .config_list = config_list,
679         .dev_open = dev_open,
680         .dev_close = dev_close,
681         .dev_acquisition_start = dev_acquisition_start,
682         .dev_acquisition_stop = dev_acquisition_stop,
683         .context = NULL,
684 };
685
686 static struct sr_dev_driver hp_ib_pps_driver_info = {
687         .name = "hpib-pps",
688         .longname = "HP-IB PPS",
689         .api_version = 1,
690         .init = std_init,
691         .cleanup = std_cleanup,
692         .scan = scan_hpib_pps,
693         .dev_list = std_dev_list,
694         .dev_clear = dev_clear,
695         .config_get = config_get,
696         .config_set = config_set,
697         .config_list = config_list,
698         .dev_open = dev_open,
699         .dev_close = dev_close,
700         .dev_acquisition_start = dev_acquisition_start,
701         .dev_acquisition_stop = dev_acquisition_stop,
702         .context = NULL,
703 };
704 SR_REGISTER_DEV_DRIVER(scpi_pps_driver_info);
705 SR_REGISTER_DEV_DRIVER(hp_ib_pps_driver_info);