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sr_dev_close(): Factor out SR_ERR_DEV_CLOSED check.
[libsigrok.git] / src / hardware / hung-chang-dso-2100 / api.c
1 /*
2  * This file is part of the libsigrok project.
3  *
4  * Copyright (C) 2015 Daniel Glöckner <daniel-gl@gmx.net>
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 <ieee1284.h>
22 #include <string.h>
23 #include "protocol.h"
24
25 static const uint32_t scanopts[] = {
26         SR_CONF_CONN,
27 };
28
29 static const uint32_t drvopts[] = {
30         SR_CONF_OSCILLOSCOPE,
31 };
32
33 static const uint32_t devopts[] = {
34         SR_CONF_CONN | SR_CONF_GET,
35         SR_CONF_LIMIT_FRAMES | SR_CONF_GET | SR_CONF_SET,
36         SR_CONF_SAMPLERATE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
37         SR_CONF_TRIGGER_SOURCE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
38         SR_CONF_TRIGGER_SLOPE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
39         SR_CONF_BUFFERSIZE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
40 };
41
42 static const uint32_t cgopts[] = {
43         SR_CONF_VDIV | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
44         SR_CONF_COUPLING | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
45         SR_CONF_PROBE_FACTOR | SR_CONF_GET | SR_CONF_SET,
46 };
47
48 static const uint64_t samplerates[] = {
49         SR_MHZ(100), SR_MHZ(50),  SR_MHZ(25),   SR_MHZ(20),
50         SR_MHZ(10),  SR_MHZ(5),   SR_KHZ(2500), SR_MHZ(2),
51         SR_MHZ(1),   SR_KHZ(500), SR_KHZ(250),  SR_KHZ(200),
52         SR_KHZ(100), SR_KHZ(50),  SR_KHZ(25),   SR_KHZ(20),
53         SR_KHZ(10),  SR_KHZ(5),   SR_HZ(2500),  SR_KHZ(2),
54         SR_KHZ(1),   SR_HZ(500),  SR_HZ(250),   SR_HZ(200),
55         SR_HZ(100),  SR_HZ(50),   SR_HZ(25),    SR_HZ(20)
56 };
57
58 /* must be in sync with readout_steps[] in protocol.c */
59 static const uint64_t buffersizes[] = {
60         2 * 500, 3 * 500, 4 * 500, 5 * 500,
61         6 * 500, 7 * 500, 8 * 500, 9 * 500, 10 * 500,
62         12 * 500 - 2, 14 * 500 - 2, 16 * 500 - 2,
63         18 * 500 - 2, 20 * 500 - 2, 10240 - 2
64 };
65
66 static const uint64_t vdivs[][2] = {
67         { 10, 1000 },
68         { 20, 1000 },
69         { 50, 1000 },
70         { 100, 1000 },
71         { 200, 1000 },
72         { 500, 1000 },
73         { 1, 1 },
74         { 2, 1 },
75         { 5, 1 },
76 };
77
78 /* Bits 4 and 5 enable relays that add /10 filters to the chain
79  * Bits 0 and 1 select an output from a resistor array */
80 static const uint8_t vdivs_map[] = {
81         0x01, 0x02, 0x03, 0x21, 0x22, 0x23, 0x31, 0x32, 0x33
82 };
83
84
85 static const char *trigger_sources[] = {
86         "A", "B", "EXT"
87 };
88
89 static const uint8_t trigger_sources_map[] = {
90         0x00, 0x80, 0x40
91 };
92
93 static const char *trigger_slopes[] = {
94         "f", "r"
95 };
96
97 static const char *coupling[] = {
98         "DC", "AC", "GND"
99 };
100
101 static const uint8_t coupling_map[] = {
102         0x00, 0x08, 0x04
103 };
104
105 static GSList *scan_port(GSList *devices, struct parport *port)
106 {
107         struct sr_dev_inst *sdi;
108         struct sr_channel *ch;
109         struct sr_channel_group *cg;
110         struct dev_context *devc;
111         int i;
112
113         if (ieee1284_open(port, 0, &i) != E1284_OK) {
114                 sr_err("Can't open parallel port %s", port->name);
115                 goto fail1;
116         }
117
118         if ((i & (CAP1284_RAW | CAP1284_BYTE)) != (CAP1284_RAW | CAP1284_BYTE)) {
119                 sr_err("Parallel port %s does not provide low-level bidirection access",
120                        port->name);
121                 goto fail2;
122         }
123
124         if (ieee1284_claim(port) != E1284_OK) {
125                 sr_err("Parallel port %s already in use", port->name);
126                 goto fail2;
127         }
128
129         if (!hung_chang_dso_2100_check_id(port))
130                 goto fail3;
131
132         sdi = g_malloc0(sizeof(struct sr_dev_inst));
133         sdi->status = SR_ST_INACTIVE;
134         sdi->vendor = g_strdup("Hung-Chang");
135         sdi->model = g_strdup("DSO-2100");
136         sdi->inst_type = 0; /* FIXME */
137         sdi->conn = port;
138         ieee1284_ref(port);
139
140         for (i = 0; i < NUM_CHANNELS; i++) {
141                 cg = g_malloc0(sizeof(struct sr_channel_group));
142                 cg->name = g_strdup(trigger_sources[i]);
143                 ch = sr_channel_new(sdi, i, SR_CHANNEL_ANALOG, FALSE, trigger_sources[i]);
144                 cg->channels = g_slist_append(cg->channels, ch);
145                 sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
146         }
147
148         devc = g_malloc0(sizeof(struct dev_context));
149         devc->enabled_channel = g_slist_append(NULL, NULL);
150         devc->channel = 0;
151         devc->rate = 0;
152         devc->probe[0] = 10;
153         devc->probe[1] = 10;
154         devc->cctl[0] = 0x31; /* 1V/div, DC coupling, trigger on channel A*/
155         devc->cctl[1] = 0x31; /* 1V/div, DC coupling, no tv sync trigger */
156         devc->edge = 0;
157         devc->tlevel = 0x80;
158         devc->pos[0] = 0x80;
159         devc->pos[1] = 0x80;
160         devc->offset[0] = 0x80;
161         devc->offset[1] = 0x80;
162         devc->gain[0] = 0x80;
163         devc->gain[1] = 0x80;
164         devc->frame_limit = 0;
165         devc->last_step = 0; /* buffersize = 1000 */
166         sdi->priv = devc;
167
168         devices = g_slist_append(devices, sdi);
169
170 fail3:
171         ieee1284_release(port);
172 fail2:
173         ieee1284_close(port);
174 fail1:
175         return devices;
176 }
177
178 static GSList *scan(struct sr_dev_driver *di, GSList *options)
179 {
180         struct parport_list ports;
181         struct sr_config *src;
182         const char *conn = NULL;
183         GSList *devices, *option;
184         gboolean port_found;
185         int i;
186
187
188         for (option = options; option; option = option->next) {
189                 src = option->data;
190                 if (src->key == SR_CONF_CONN) {
191                         conn = g_variant_get_string(src->data, NULL);
192                         break;
193                 }
194         }
195
196         if (!conn)
197                 return NULL;
198
199         if (ieee1284_find_ports(&ports, 0) != E1284_OK)
200                 return NULL;
201
202         devices = NULL;
203         port_found = FALSE;
204         for (i = 0; i < ports.portc; i++)
205                 if (!strcmp(ports.portv[i]->name, conn)) {
206                         port_found = TRUE;
207                         devices = scan_port(devices, ports.portv[i]);
208                 }
209
210         if (!port_found) {
211                 sr_err("Parallel port %s not found. Valid names are:", conn);
212                 for (i = 0; i < ports.portc; i++)
213                         sr_err("\t%s", ports.portv[i]->name);
214         }
215
216         ieee1284_free_ports(&ports);
217
218         return std_scan_complete(di, devices);
219 }
220
221 static void clear_private(void *priv)
222 {
223         struct dev_context *devc = priv;
224
225         g_slist_free(devc->enabled_channel);
226 }
227
228 static int dev_clear(const struct sr_dev_driver *di)
229 {
230         struct drv_context *drvc = di->context;
231         struct sr_dev_inst *sdi;
232         GSList *l;
233
234         if (drvc) {
235                 for (l = drvc->instances; l; l = l->next) {
236                         sdi = l->data;
237                         ieee1284_unref(sdi->conn);
238                 }
239         }
240
241         return std_dev_clear(di, clear_private);
242 }
243
244 static int dev_open(struct sr_dev_inst *sdi)
245 {
246         struct dev_context *devc = sdi->priv;
247         int i;
248
249         if (sdi->status != SR_ST_INACTIVE)
250                 goto fail1;
251
252         if (ieee1284_open(sdi->conn, 0, &i) != E1284_OK)
253                 goto fail1;
254
255         if (ieee1284_claim(sdi->conn) != E1284_OK)
256                 goto fail2;
257
258         if (ieee1284_data_dir(sdi->conn, 1) != E1284_OK)
259                 goto fail3;
260
261         if (hung_chang_dso_2100_move_to(sdi, 1))
262                 goto fail3;
263
264         devc->samples = g_try_malloc(1000 * sizeof(*devc->samples));
265         if (!devc->samples)
266                 goto fail3;
267
268         sdi->status = SR_ST_ACTIVE;
269
270         return SR_OK;
271
272 fail3:
273         hung_chang_dso_2100_reset_port(sdi->conn);
274         ieee1284_release(sdi->conn);
275 fail2:
276         ieee1284_close(sdi->conn);
277 fail1:
278         return SR_ERR;
279 }
280
281 static int dev_close(struct sr_dev_inst *sdi)
282 {
283         struct dev_context *devc = sdi->priv;
284
285         g_free(devc->samples);
286         hung_chang_dso_2100_reset_port(sdi->conn);
287         ieee1284_release(sdi->conn);
288         ieee1284_close(sdi->conn);
289
290         sdi->status = SR_ST_INACTIVE;
291
292         return SR_OK;
293 }
294
295 static int find_in_array(GVariant *data, const GVariantType *type,
296                          const void *arr, int n)
297 {
298         const char * const *sarr;
299         const char *s;
300         const uint64_t *u64arr;
301         const uint8_t *u8arr;
302         uint64_t u64;
303         uint8_t u8;
304         int i;
305
306         if (!g_variant_is_of_type(data, type))
307                 return -1;
308
309         switch (g_variant_classify(data)) {
310         case G_VARIANT_CLASS_STRING:
311                 s = g_variant_get_string(data, NULL);
312                 sarr = arr;
313
314                 for (i = 0; i < n; i++)
315                         if (!strcmp(s, sarr[i]))
316                                 return i;
317                 break;
318         case G_VARIANT_CLASS_UINT64:
319                 u64 = g_variant_get_uint64(data);
320                 u64arr = arr;
321
322                 for (i = 0; i < n; i++)
323                         if (u64 == u64arr[i])
324                                 return i;
325                 break;
326         case G_VARIANT_CLASS_BYTE:
327                 u8 = g_variant_get_byte(data);
328                 u8arr = arr;
329
330                 for (i = 0; i < n; i++)
331                         if (u8 == u8arr[i])
332                                 return i;
333         default:
334                 break;
335         }
336
337         return -1;
338 }
339
340 static int reverse_map(uint8_t u, const uint8_t *arr, int n)
341 {
342         GVariant *v = g_variant_new_byte(u);
343         int i = find_in_array(v, G_VARIANT_TYPE_BYTE, arr, n);
344         g_variant_unref(v);
345         return i;
346 }
347
348 static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
349                 const struct sr_channel_group *cg)
350 {
351         struct dev_context *devc = sdi->priv;
352         struct parport *port;
353         int ret, i, ch = -1;
354
355         if (cg) /* sr_config_get will validate cg using config_list */
356                 ch = ((struct sr_channel *)cg->channels->data)->index;
357
358         ret = SR_OK;
359         switch (key) {
360         case SR_CONF_CONN:
361                 port = sdi->conn;
362                 *data = g_variant_new_string(port->name);
363                 break;
364         case SR_CONF_LIMIT_FRAMES:
365                 *data = g_variant_new_uint64(devc->frame_limit);
366                 break;
367         case SR_CONF_SAMPLERATE:
368                 *data = g_variant_new_uint64(samplerates[devc->rate]);
369                 break;
370         case SR_CONF_TRIGGER_SOURCE:
371                 i = reverse_map(devc->cctl[0] & 0xC0, trigger_sources_map,
372                                 ARRAY_SIZE(trigger_sources_map));
373                 if (i == -1)
374                         ret = SR_ERR;
375                 else
376                         *data = g_variant_new_string(trigger_sources[i]);
377                 break;
378         case SR_CONF_TRIGGER_SLOPE:
379                 if (devc->edge >= ARRAY_SIZE(trigger_slopes))
380                         ret = SR_ERR;
381                 else
382                         *data = g_variant_new_string(trigger_slopes[devc->edge]);
383                 break;
384         case SR_CONF_BUFFERSIZE:
385                 *data = g_variant_new_uint64(buffersizes[devc->last_step]);
386                 break;
387         case SR_CONF_VDIV:
388                 if (ch == -1) {
389                         ret = SR_ERR_CHANNEL_GROUP;
390                 } else {
391                         i = reverse_map(devc->cctl[ch] & 0x33, vdivs_map,
392                                         ARRAY_SIZE(vdivs_map));
393                         if (i == -1)
394                                 ret = SR_ERR;
395                         else
396                                 *data = g_variant_new("(tt)", vdivs[i][0],
397                                                       vdivs[i][1]);
398                 }
399                 break;
400         case SR_CONF_COUPLING:
401                 if (ch == -1) {
402                         ret = SR_ERR_CHANNEL_GROUP;
403                 } else {
404                         i = reverse_map(devc->cctl[ch] & 0x0C, coupling_map,
405                                         ARRAY_SIZE(coupling_map));
406                         if (i == -1)
407                                 ret = SR_ERR;
408                         else
409                                 *data = g_variant_new_string(coupling[i]);
410                 }
411                 break;
412         case SR_CONF_PROBE_FACTOR:
413                 if (ch == -1)
414                         ret = SR_ERR_CHANNEL_GROUP;
415                 else
416                         *data = g_variant_new_uint64(devc->probe[ch]);
417                 break;
418         default:
419                 ret = SR_ERR_NA;
420         }
421
422         return ret;
423 }
424
425 static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
426                 const struct sr_channel_group *cg)
427 {
428         struct dev_context *devc = sdi->priv;
429         int ret, i, ch = -1;
430         uint64_t u, v;
431
432         if (cg) /* sr_config_set will validate cg using config_list */
433                 ch = ((struct sr_channel *)cg->channels->data)->index;
434
435         ret = SR_OK;
436         switch (key) {
437         case SR_CONF_LIMIT_FRAMES:
438                 devc->frame_limit = g_variant_get_uint64(data);
439                 break;
440         case SR_CONF_SAMPLERATE:
441                 i = find_in_array(data, G_VARIANT_TYPE_UINT64,
442                                   samplerates, ARRAY_SIZE(samplerates));
443                 if (i == -1)
444                         ret = SR_ERR_ARG;
445                 else
446                         devc->rate = i;
447                 break;
448         case SR_CONF_TRIGGER_SOURCE:
449                 i = find_in_array(data, G_VARIANT_TYPE_STRING,
450                                   trigger_sources, ARRAY_SIZE(trigger_sources));
451                 if (i == -1)
452                         ret = SR_ERR_ARG;
453                 else
454                         devc->cctl[0] = (devc->cctl[0] & 0x3F)
455                                       | trigger_sources_map[i];
456                 break;
457         case SR_CONF_TRIGGER_SLOPE:
458                 i = find_in_array(data, G_VARIANT_TYPE_STRING,
459                                   trigger_slopes, ARRAY_SIZE(trigger_slopes));
460                 if (i == -1)
461                         ret = SR_ERR_ARG;
462                 else
463                         devc->edge = i;
464                 break;
465         case SR_CONF_BUFFERSIZE:
466                 i = find_in_array(data, G_VARIANT_TYPE_UINT64,
467                                   buffersizes, ARRAY_SIZE(buffersizes));
468                 if (i == -1)
469                         ret = SR_ERR_ARG;
470                 else
471                         devc->last_step = i;
472                 break;
473         case SR_CONF_VDIV:
474                 if (ch == -1) {
475                         ret = SR_ERR_CHANNEL_GROUP;
476                 } else if (!g_variant_is_of_type(data, G_VARIANT_TYPE("(tt)"))) {
477                         ret = SR_ERR_ARG;
478                 } else {
479                         g_variant_get(data, "(tt)", &u, &v);
480                         for (i = 0; i < (int)ARRAY_SIZE(vdivs); i++)
481                                 if (vdivs[i][0] == u && vdivs[i][1] == v)
482                                         break;
483                         if (i == ARRAY_SIZE(vdivs))
484                                 ret = SR_ERR_ARG;
485                         else
486                                 devc->cctl[ch] = (devc->cctl[ch] & 0xCC)
487                                                | vdivs_map[i];
488                 }
489                 break;
490         case SR_CONF_COUPLING:
491                 if (ch == -1) {
492                         ret = SR_ERR_CHANNEL_GROUP;
493                 } else {
494                         i = find_in_array(data, G_VARIANT_TYPE_STRING,
495                                           coupling, ARRAY_SIZE(coupling));
496                         if (i == -1)
497                                 ret = SR_ERR_ARG;
498                         else
499                                 devc->cctl[ch] = (devc->cctl[ch] & 0xF3)
500                                                | coupling_map[i];
501                 }
502                 break;
503         case SR_CONF_PROBE_FACTOR:
504                 if (ch == -1) {
505                         ret = SR_ERR_CHANNEL_GROUP;
506                 } else {
507                         u = g_variant_get_uint64(data);
508                         if (!u)
509                                 ret = SR_ERR_ARG;
510                         else
511                                 devc->probe[ch] = u;
512                 }
513                 break;
514         default:
515                 ret = SR_ERR_NA;
516         }
517
518         return ret;
519 }
520
521 static int config_channel_set(const struct sr_dev_inst *sdi,
522                               struct sr_channel *ch,
523                               unsigned int changes)
524 {
525         struct dev_context *devc = sdi->priv;
526         uint8_t v;
527
528         if (changes & SR_CHANNEL_SET_ENABLED) {
529                 if (ch->enabled) {
530                         v = devc->channel | (1 << ch->index);
531                         if (v & (v - 1))
532                                 return SR_ERR;
533                         devc->channel = v;
534                         devc->enabled_channel->data = ch;
535                 } else {
536                         devc->channel &= ~(1 << ch->index);
537                 }
538         }
539         return SR_OK;
540 }
541
542 static int config_commit(const struct sr_dev_inst *sdi)
543 {
544         uint8_t state = hung_chang_dso_2100_read_mbox(sdi->conn, 0.02);
545         int ret;
546
547         switch (state) {
548         case 0x03:
549         case 0x14:
550         case 0x21:
551                 /* we will travel the complete config path on our way to state 1 */
552                 break;
553         case 0x00:
554                 state = 0x01;
555                 /* Fallthrough */
556         default:
557                 ret = hung_chang_dso_2100_move_to(sdi, 1);
558                 if (ret != SR_OK)
559                         return ret;
560                 /* Fallthrough */
561         case 0x01:
562                 hung_chang_dso_2100_write_mbox(sdi->conn, 4);
563         }
564         ret = hung_chang_dso_2100_move_to(sdi, 1);
565         if (ret != SR_OK)
566                 return ret;
567         return hung_chang_dso_2100_move_to(sdi, state);
568 }
569
570 static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
571                 const struct sr_channel_group *cg)
572 {
573         GVariantBuilder gvb;
574         GVariant *gvar, *rational[2];
575         GSList *l;
576         int i;
577
578         switch (key) {
579                 case SR_CONF_SCAN_OPTIONS:
580         case SR_CONF_DEVICE_OPTIONS:
581                 break;
582         case SR_CONF_SAMPLERATE:
583         case SR_CONF_TRIGGER_SOURCE:
584         case SR_CONF_TRIGGER_SLOPE:
585         case SR_CONF_BUFFERSIZE:
586                 if (!sdi || cg)
587                         return SR_ERR_NA;
588                 break;
589         case SR_CONF_VDIV:
590         case SR_CONF_COUPLING:
591                 if (!sdi)
592                         return SR_ERR_NA;
593                 if (!cg)
594                         return SR_ERR_CHANNEL_GROUP;
595                 l = g_slist_find(sdi->channel_groups, cg);
596                 if (!l)
597                         return SR_ERR_ARG;
598                 break;
599         default:
600                 return SR_ERR_NA;
601         }
602
603         switch (key) {
604         case SR_CONF_SCAN_OPTIONS:
605                 *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
606                                 scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
607                 break;
608         case SR_CONF_DEVICE_OPTIONS:
609                 if (!sdi)
610                         *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
611                                         drvopts, ARRAY_SIZE(drvopts), sizeof(uint32_t));
612                 else if (!cg)
613                         *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
614                                         devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
615                 else
616                         *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
617                                         cgopts, ARRAY_SIZE(cgopts), sizeof(uint32_t));
618                 break;
619         case SR_CONF_SAMPLERATE:
620                 g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
621                 gvar = g_variant_new_fixed_array(G_VARIANT_TYPE("t"),
622                                 samplerates, ARRAY_SIZE(samplerates), sizeof(uint64_t));
623                 g_variant_builder_add(&gvb, "{sv}", "samplerates", gvar);
624                 *data = g_variant_builder_end(&gvb);
625                 break;
626         case SR_CONF_TRIGGER_SOURCE:
627                 *data = g_variant_new_strv(trigger_sources, ARRAY_SIZE(trigger_sources));
628                 break;
629         case SR_CONF_TRIGGER_SLOPE:
630                 *data = g_variant_new_strv(trigger_slopes, ARRAY_SIZE(trigger_slopes));
631                 break;
632         case SR_CONF_BUFFERSIZE:
633                 *data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT64,
634                                 buffersizes, ARRAY_SIZE(buffersizes), sizeof(uint64_t));
635                 break;
636         case SR_CONF_VDIV:
637                 g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
638                 for (i = 0; i < (int)ARRAY_SIZE(vdivs); i++) {
639                         rational[0] = g_variant_new_uint64(vdivs[i][0]);
640                         rational[1] = g_variant_new_uint64(vdivs[i][1]);
641                         gvar = g_variant_new_tuple(rational, 2);
642                         g_variant_builder_add_value(&gvb, gvar);
643                 }
644                 *data = g_variant_builder_end(&gvb);
645                 break;
646         case SR_CONF_COUPLING:
647                 *data = g_variant_new_strv(coupling, ARRAY_SIZE(coupling));
648                 break;
649         }
650
651         return SR_OK;
652 }
653
654 static int dev_acquisition_start(const struct sr_dev_inst *sdi)
655 {
656         struct dev_context *devc = sdi->priv;
657         int ret;
658
659         if (devc->channel) {
660                 static const float res_array[] = {0.5, 1, 2, 5};
661                 static const uint8_t relays[] = {100, 10, 10, 1};
662                 devc->factor = devc->probe[devc->channel - 1] / 32.0;
663                 devc->factor *= res_array[devc->cctl[devc->channel - 1] & 0x03];
664                 devc->factor /= relays[(devc->cctl[devc->channel - 1] >> 4) & 0x03];
665         }
666         devc->frame = 0;
667         devc->state_known = TRUE;
668         devc->step = 0;
669         devc->adc2 = FALSE;
670         devc->retries = MAX_RETRIES;
671
672         ret = hung_chang_dso_2100_move_to(sdi, 0x21);
673         if (ret != SR_OK)
674                 return ret;
675
676         std_session_send_df_header(sdi);
677
678         sr_session_source_add(sdi->session, -1, 0, 8,
679                               hung_chang_dso_2100_poll, (void *)sdi);
680
681         return SR_OK;
682 }
683
684 static int dev_acquisition_stop(struct sr_dev_inst *sdi)
685 {
686         std_session_send_df_end(sdi);
687         sr_session_source_remove(sdi->session, -1);
688         hung_chang_dso_2100_move_to(sdi, 1);
689
690         return SR_OK;
691 }
692
693 static struct sr_dev_driver hung_chang_dso_2100_driver_info = {
694         .name = "hung-chang-dso-2100",
695         .longname = "Hung-Chang DSO-2100",
696         .api_version = 1,
697         .init = std_init,
698         .cleanup = std_cleanup,
699         .scan = scan,
700         .dev_list = std_dev_list,
701         .dev_clear = dev_clear,
702         .config_get = config_get,
703         .config_set = config_set,
704         .config_channel_set = config_channel_set,
705         .config_commit = config_commit,
706         .config_list = config_list,
707         .dev_open = dev_open,
708         .dev_close = dev_close,
709         .dev_acquisition_start = dev_acquisition_start,
710         .dev_acquisition_stop = dev_acquisition_stop,
711         .context = NULL,
712 };
713 SR_REGISTER_DEV_DRIVER(hung_chang_dso_2100_driver_info);