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 devopts_cg[] = {
  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_helper(struct dev_context *devc)
 222 {
 223         g_slist_free(devc->enabled_channel);
 224 }
 225
 226 static int dev_clear(const struct sr_dev_driver *di)
 227 {
 228         struct drv_context *drvc = di->context;
 229         struct sr_dev_inst *sdi;
 230         GSList *l;
 231
 232         if (drvc) {
 233                 for (l = drvc->instances; l; l = l->next) {
 234                         sdi = l->data;
 235                         ieee1284_unref(sdi->conn);
 236                 }
 237         }
 238
 239         return std_dev_clear_with_callback(di, (std_dev_clear_callback)clear_helper);
 240 }
 241
 242 static int dev_open(struct sr_dev_inst *sdi)
 243 {
 244         struct dev_context *devc = sdi->priv;
 245         int i;
 246
 247         if (ieee1284_open(sdi->conn, 0, &i) != E1284_OK)
 248                 goto fail1;
 249
 250         if (ieee1284_claim(sdi->conn) != E1284_OK)
 251                 goto fail2;
 252
 253         if (ieee1284_data_dir(sdi->conn, 1) != E1284_OK)
 254                 goto fail3;
 255
 256         if (hung_chang_dso_2100_move_to(sdi, 1))
 257                 goto fail3;
 258
 259         devc->samples = g_try_malloc(1000 * sizeof(*devc->samples));
 260         if (!devc->samples)
 261                 goto fail3;
 262
 263         return SR_OK;
 264
 265 fail3:
 266         hung_chang_dso_2100_reset_port(sdi->conn);
 267         ieee1284_release(sdi->conn);
 268 fail2:
 269         ieee1284_close(sdi->conn);
 270 fail1:
 271         return SR_ERR;
 272 }
 273
 274 static int dev_close(struct sr_dev_inst *sdi)
 275 {
 276         struct dev_context *devc = sdi->priv;
 277
 278         g_free(devc->samples);
 279         hung_chang_dso_2100_reset_port(sdi->conn);
 280         ieee1284_release(sdi->conn);
 281         ieee1284_close(sdi->conn);
 282
 283         return SR_OK;
 284 }
 285
 286 static int find_in_array(GVariant *data, const GVariantType *type,
 287                          const void *arr, int n)
 288 {
 289         const char * const *sarr;
 290         const char *s;
 291         const uint64_t *u64arr;
 292         const uint8_t *u8arr;
 293         uint64_t u64;
 294         uint8_t u8;
 295         int i;
 296
 297         if (!g_variant_is_of_type(data, type))
 298                 return -1;
 299
 300         switch (g_variant_classify(data)) {
 301         case G_VARIANT_CLASS_STRING:
 302                 s = g_variant_get_string(data, NULL);
 303                 sarr = arr;
 304
 305                 for (i = 0; i < n; i++)
 306                         if (!strcmp(s, sarr[i]))
 307                                 return i;
 308                 break;
 309         case G_VARIANT_CLASS_UINT64:
 310                 u64 = g_variant_get_uint64(data);
 311                 u64arr = arr;
 312
 313                 for (i = 0; i < n; i++)
 314                         if (u64 == u64arr[i])
 315                                 return i;
 316                 break;
 317         case G_VARIANT_CLASS_BYTE:
 318                 u8 = g_variant_get_byte(data);
 319                 u8arr = arr;
 320
 321                 for (i = 0; i < n; i++)
 322                         if (u8 == u8arr[i])
 323                                 return i;
 324         default:
 325                 break;
 326         }
 327
 328         return -1;
 329 }
 330
 331 static int reverse_map(uint8_t u, const uint8_t *arr, int n)
 332 {
 333         GVariant *v = g_variant_new_byte(u);
 334         int i = find_in_array(v, G_VARIANT_TYPE_BYTE, arr, n);
 335         g_variant_unref(v);
 336         return i;
 337 }
 338
 339 static int config_get(uint32_t key, GVariant **data,
 340         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 341 {
 342         struct dev_context *devc = sdi->priv;
 343         struct parport *port;
 344         int i, ch = -1;
 345
 346         if (cg) /* sr_config_get will validate cg using config_list */
 347                 ch = ((struct sr_channel *)cg->channels->data)->index;
 348
 349         switch (key) {
 350         case SR_CONF_CONN:
 351                 port = sdi->conn;
 352                 *data = g_variant_new_string(port->name);
 353                 break;
 354         case SR_CONF_LIMIT_FRAMES:
 355                 *data = g_variant_new_uint64(devc->frame_limit);
 356                 break;
 357         case SR_CONF_SAMPLERATE:
 358                 *data = g_variant_new_uint64(samplerates[devc->rate]);
 359                 break;
 360         case SR_CONF_TRIGGER_SOURCE:
 361                 i = reverse_map(devc->cctl[0] & 0xC0, ARRAY_AND_SIZE(trigger_sources_map));
 362                 if (i == -1)
 363                         return SR_ERR;
 364                 else
 365                         *data = g_variant_new_string(trigger_sources[i]);
 366                 break;
 367         case SR_CONF_TRIGGER_SLOPE:
 368                 if (devc->edge >= ARRAY_SIZE(trigger_slopes))
 369                         return SR_ERR;
 370                 else
 371                         *data = g_variant_new_string(trigger_slopes[devc->edge]);
 372                 break;
 373         case SR_CONF_BUFFERSIZE:
 374                 *data = g_variant_new_uint64(buffersizes[devc->last_step]);
 375                 break;
 376         case SR_CONF_VDIV:
 377                 if (ch == -1) {
 378                         return SR_ERR_CHANNEL_GROUP;
 379                 } else {
 380                         i = reverse_map(devc->cctl[ch] & 0x33, ARRAY_AND_SIZE(vdivs_map));
 381                         if (i == -1)
 382                                 return SR_ERR;
 383                         else
 384                                 *data = g_variant_new("(tt)", vdivs[i][0],
 385                                                       vdivs[i][1]);
 386                 }
 387                 break;
 388         case SR_CONF_COUPLING:
 389                 if (ch == -1) {
 390                         return SR_ERR_CHANNEL_GROUP;
 391                 } else {
 392                         i = reverse_map(devc->cctl[ch] & 0x0C, ARRAY_AND_SIZE(coupling_map));
 393                         if (i == -1)
 394                                 return SR_ERR;
 395                         else
 396                                 *data = g_variant_new_string(coupling[i]);
 397                 }
 398                 break;
 399         case SR_CONF_PROBE_FACTOR:
 400                 if (ch == -1)
 401                         return SR_ERR_CHANNEL_GROUP;
 402                 else
 403                         *data = g_variant_new_uint64(devc->probe[ch]);
 404                 break;
 405         default:
 406                 return SR_ERR_NA;
 407         }
 408
 409         return SR_OK;
 410 }
 411
 412 static int config_set(uint32_t key, GVariant *data,
 413         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 414 {
 415         struct dev_context *devc = sdi->priv;
 416         int i, ch = -1;
 417         uint64_t u, v;
 418
 419         if (cg) /* sr_config_set will validate cg using config_list */
 420                 ch = ((struct sr_channel *)cg->channels->data)->index;
 421
 422         switch (key) {
 423         case SR_CONF_LIMIT_FRAMES:
 424                 devc->frame_limit = g_variant_get_uint64(data);
 425                 break;
 426         case SR_CONF_SAMPLERATE:
 427                 i = find_in_array(data, G_VARIANT_TYPE_UINT64,
 428                                   ARRAY_AND_SIZE(samplerates));
 429                 if (i == -1)
 430                         return SR_ERR_ARG;
 431                 else
 432                         devc->rate = i;
 433                 break;
 434         case SR_CONF_TRIGGER_SOURCE:
 435                 i = find_in_array(data, G_VARIANT_TYPE_STRING,
 436                                   ARRAY_AND_SIZE(trigger_sources));
 437                 if (i == -1)
 438                         return SR_ERR_ARG;
 439                 else
 440                         devc->cctl[0] = (devc->cctl[0] & 0x3F)
 441                                       | trigger_sources_map[i];
 442                 break;
 443         case SR_CONF_TRIGGER_SLOPE:
 444                 i = find_in_array(data, G_VARIANT_TYPE_STRING,
 445                                   ARRAY_AND_SIZE(trigger_slopes));
 446                 if (i == -1)
 447                         return SR_ERR_ARG;
 448                 else
 449                         devc->edge = i;
 450                 break;
 451         case SR_CONF_BUFFERSIZE:
 452                 i = find_in_array(data, G_VARIANT_TYPE_UINT64,
 453                                   ARRAY_AND_SIZE(buffersizes));
 454                 if (i == -1)
 455                         return SR_ERR_ARG;
 456                 else
 457                         devc->last_step = i;
 458                 break;
 459         case SR_CONF_VDIV:
 460                 if (ch == -1) {
 461                         return SR_ERR_CHANNEL_GROUP;
 462                 } else if (!g_variant_is_of_type(data, G_VARIANT_TYPE("(tt)"))) {
 463                         return SR_ERR_ARG;
 464                 } else {
 465                         g_variant_get(data, "(tt)", &u, &v);
 466                         for (i = 0; i < (int)ARRAY_SIZE(vdivs); i++)
 467                                 if (vdivs[i][0] == u && vdivs[i][1] == v)
 468                                         break;
 469                         if (i == ARRAY_SIZE(vdivs))
 470                                 return SR_ERR_ARG;
 471                         else
 472                                 devc->cctl[ch] = (devc->cctl[ch] & 0xCC)
 473                                                | vdivs_map[i];
 474                 }
 475                 break;
 476         case SR_CONF_COUPLING:
 477                 if (ch == -1) {
 478                         return SR_ERR_CHANNEL_GROUP;
 479                 } else {
 480                         i = find_in_array(data, G_VARIANT_TYPE_STRING,
 481                                           ARRAY_AND_SIZE(coupling));
 482                         if (i == -1)
 483                                 return SR_ERR_ARG;
 484                         else
 485                                 devc->cctl[ch] = (devc->cctl[ch] & 0xF3)
 486                                                | coupling_map[i];
 487                 }
 488                 break;
 489         case SR_CONF_PROBE_FACTOR:
 490                 if (ch == -1) {
 491                         return SR_ERR_CHANNEL_GROUP;
 492                 } else {
 493                         u = g_variant_get_uint64(data);
 494                         if (!u)
 495                                 return SR_ERR_ARG;
 496                         else
 497                                 devc->probe[ch] = u;
 498                 }
 499                 break;
 500         default:
 501                 return SR_ERR_NA;
 502         }
 503
 504         return SR_OK;
 505 }
 506
 507 static int config_channel_set(const struct sr_dev_inst *sdi,
 508         struct sr_channel *ch, unsigned int changes)
 509 {
 510         struct dev_context *devc = sdi->priv;
 511         uint8_t v;
 512
 513         if (changes & SR_CHANNEL_SET_ENABLED) {
 514                 if (ch->enabled) {
 515                         v = devc->channel | (1 << ch->index);
 516                         if (v & (v - 1))
 517                                 return SR_ERR;
 518                         devc->channel = v;
 519                         devc->enabled_channel->data = ch;
 520                 } else {
 521                         devc->channel &= ~(1 << ch->index);
 522                 }
 523         }
 524         return SR_OK;
 525 }
 526
 527 static int config_commit(const struct sr_dev_inst *sdi)
 528 {
 529         uint8_t state = hung_chang_dso_2100_read_mbox(sdi->conn, 0.02);
 530         int ret;
 531
 532         switch (state) {
 533         case 0x03:
 534         case 0x14:
 535         case 0x21:
 536                 /* we will travel the complete config path on our way to state 1 */
 537                 break;
 538         case 0x00:
 539                 state = 0x01;
 540                 /* Fallthrough */
 541         default:
 542                 ret = hung_chang_dso_2100_move_to(sdi, 1);
 543                 if (ret != SR_OK)
 544                         return ret;
 545                 /* Fallthrough */
 546         case 0x01:
 547                 hung_chang_dso_2100_write_mbox(sdi->conn, 4);
 548         }
 549         ret = hung_chang_dso_2100_move_to(sdi, 1);
 550         if (ret != SR_OK)
 551                 return ret;
 552         return hung_chang_dso_2100_move_to(sdi, state);
 553 }
 554
 555 static int config_list(uint32_t key, GVariant **data,
 556         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 557 {
 558         GSList *l;
 559
 560         switch (key) {
 561         case SR_CONF_SCAN_OPTIONS:
 562         case SR_CONF_DEVICE_OPTIONS:
 563                 break;
 564         case SR_CONF_SAMPLERATE:
 565         case SR_CONF_TRIGGER_SOURCE:
 566         case SR_CONF_TRIGGER_SLOPE:
 567         case SR_CONF_BUFFERSIZE:
 568                 if (!sdi || cg)
 569                         return SR_ERR_NA;
 570                 break;
 571         case SR_CONF_VDIV:
 572         case SR_CONF_COUPLING:
 573                 if (!sdi)
 574                         return SR_ERR_NA;
 575                 if (!cg)
 576                         return SR_ERR_CHANNEL_GROUP;
 577                 l = g_slist_find(sdi->channel_groups, cg);
 578                 if (!l)
 579                         return SR_ERR_ARG;
 580                 break;
 581         default:
 582                 return SR_ERR_NA;
 583         }
 584
 585         switch (key) {
 586         case SR_CONF_SCAN_OPTIONS:
 587                 return STD_CONFIG_LIST(key, data, sdi, cg, scanopts, NULL, NULL);
 588         case SR_CONF_DEVICE_OPTIONS:
 589                 if (!cg)
 590                         return STD_CONFIG_LIST(key, data, sdi, cg, NULL, drvopts, devopts);
 591                 *data = std_gvar_array_u32(ARRAY_AND_SIZE(devopts_cg));
 592                 break;
 593         case SR_CONF_SAMPLERATE:
 594                 *data = std_gvar_samplerates(ARRAY_AND_SIZE(samplerates));
 595                 break;
 596         case SR_CONF_TRIGGER_SOURCE:
 597                 *data = g_variant_new_strv(ARRAY_AND_SIZE(trigger_sources));
 598                 break;
 599         case SR_CONF_TRIGGER_SLOPE:
 600                 *data = g_variant_new_strv(ARRAY_AND_SIZE(trigger_slopes));
 601                 break;
 602         case SR_CONF_BUFFERSIZE:
 603                 *data = std_gvar_array_u64(ARRAY_AND_SIZE(buffersizes));
 604                 break;
 605         case SR_CONF_VDIV:
 606                 *data = std_gvar_tuple_array(ARRAY_AND_SIZE(vdivs));
 607                 break;
 608         case SR_CONF_COUPLING:
 609                 *data = g_variant_new_strv(ARRAY_AND_SIZE(coupling));
 610                 break;
 611         }
 612
 613         return SR_OK;
 614 }
 615
 616 static int dev_acquisition_start(const struct sr_dev_inst *sdi)
 617 {
 618         struct dev_context *devc = sdi->priv;
 619         int ret;
 620
 621         if (devc->channel) {
 622                 static const float res_array[] = {0.5, 1, 2, 5};
 623                 static const uint8_t relays[] = {100, 10, 10, 1};
 624                 devc->factor = devc->probe[devc->channel - 1] / 32.0;
 625                 devc->factor *= res_array[devc->cctl[devc->channel - 1] & 0x03];
 626                 devc->factor /= relays[(devc->cctl[devc->channel - 1] >> 4) & 0x03];
 627         }
 628         devc->frame = 0;
 629         devc->state_known = TRUE;
 630         devc->step = 0;
 631         devc->adc2 = FALSE;
 632         devc->retries = MAX_RETRIES;
 633
 634         ret = hung_chang_dso_2100_move_to(sdi, 0x21);
 635         if (ret != SR_OK)
 636                 return ret;
 637
 638         std_session_send_df_header(sdi);
 639
 640         sr_session_source_add(sdi->session, -1, 0, 8,
 641                               hung_chang_dso_2100_poll, (void *)sdi);
 642
 643         return SR_OK;
 644 }
 645
 646 static int dev_acquisition_stop(struct sr_dev_inst *sdi)
 647 {
 648         std_session_send_df_end(sdi);
 649         sr_session_source_remove(sdi->session, -1);
 650         hung_chang_dso_2100_move_to(sdi, 1);
 651
 652         return SR_OK;
 653 }
 654
 655 static struct sr_dev_driver hung_chang_dso_2100_driver_info = {
 656         .name = "hung-chang-dso-2100",
 657         .longname = "Hung-Chang DSO-2100",
 658         .api_version = 1,
 659         .init = std_init,
 660         .cleanup = std_cleanup,
 661         .scan = scan,
 662         .dev_list = std_dev_list,
 663         .dev_clear = dev_clear,
 664         .config_get = config_get,
 665         .config_set = config_set,
 666         .config_channel_set = config_channel_set,
 667         .config_commit = config_commit,
 668         .config_list = config_list,
 669         .dev_open = dev_open,
 670         .dev_close = dev_close,
 671         .dev_acquisition_start = dev_acquisition_start,
 672         .dev_acquisition_stop = dev_acquisition_stop,
 673         .context = NULL,
 674 };
 675 SR_REGISTER_DEV_DRIVER(hung_chang_dso_2100_driver_info);