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