src/hardware/hantek-6xxx/api.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2015 Christer Ekholm <christerekholm@gmail.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 <math.h>
  22 #include "protocol.h"
  23
  24 /* Max time in ms before we want to check on USB events */
  25 #define TICK 200
  26
  27 #define RANGE(ch) (((float)vdivs[devc->voltage[ch]][0] / vdivs[devc->voltage[ch]][1]) * VDIV_MULTIPLIER)
  28
  29 static const uint32_t scanopts[] = {
  30         SR_CONF_CONN,
  31 };
  32
  33 static const uint32_t drvopts[] = {
  34         SR_CONF_OSCILLOSCOPE,
  35 };
  36
  37 static const uint32_t devopts[] = {
  38         SR_CONF_CONN | SR_CONF_GET,
  39         SR_CONF_LIMIT_SAMPLES | SR_CONF_GET | SR_CONF_SET,
  40         SR_CONF_LIMIT_MSEC | SR_CONF_GET | SR_CONF_SET,
  41         SR_CONF_SAMPLERATE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
  42         SR_CONF_NUM_VDIV | SR_CONF_GET,
  43 };
  44
  45 static const uint32_t devopts_cg[] = {
  46         SR_CONF_VDIV | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
  47         SR_CONF_COUPLING | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
  48 };
  49
  50 static const char *channel_names[] = {
  51         "CH1", "CH2",
  52 };
  53
  54 static const char *dc_coupling[] = {
  55         "DC",
  56 };
  57
  58 static const char *acdc_coupling[] = {
  59         "AC", "DC",
  60 };
  61
  62 static const struct hantek_6xxx_profile dev_profiles[] = {
  63         {
  64                 0x04b4, 0x6022, 0x1d50, 0x608e, 0x0001,
  65                 "Hantek", "6022BE", "fx2lafw-hantek-6022be.fw",
  66                 ARRAY_AND_SIZE(dc_coupling), FALSE,
  67         },
  68         {
  69                 0x8102, 0x8102, 0x1d50, 0x608e, 0x0002,
  70                 "Sainsmart", "DDS120", "fx2lafw-sainsmart-dds120.fw",
  71                 ARRAY_AND_SIZE(acdc_coupling), TRUE,
  72         },
  73         {
  74                 0x04b4, 0x602a, 0x1d50, 0x608e, 0x0003,
  75                 "Hantek", "6022BL", "fx2lafw-hantek-6022bl.fw",
  76                 ARRAY_AND_SIZE(dc_coupling), FALSE,
  77         },
  78         ALL_ZERO
  79 };
  80
  81 static const uint64_t samplerates[] = {
  82         SAMPLERATE_VALUES
  83 };
  84
  85 static const uint64_t vdivs[][2] = {
  86         VDIV_VALUES
  87 };
  88
  89 static int read_channel(const struct sr_dev_inst *sdi, uint32_t amount);
  90
  91 static struct sr_dev_inst *hantek_6xxx_dev_new(const struct hantek_6xxx_profile *prof)
  92 {
  93         struct sr_dev_inst *sdi;
  94         struct sr_channel *ch;
  95         struct sr_channel_group *cg;
  96         struct dev_context *devc;
  97         unsigned int i;
  98
  99         sdi = g_malloc0(sizeof(struct sr_dev_inst));
 100         sdi->status = SR_ST_INITIALIZING;
 101         sdi->vendor = g_strdup(prof->vendor);
 102         sdi->model = g_strdup(prof->model);
 103
 104         for (i = 0; i < ARRAY_SIZE(channel_names); i++) {
 105                 ch = sr_channel_new(sdi, i, SR_CHANNEL_ANALOG, TRUE, channel_names[i]);
 106                 cg = g_malloc0(sizeof(struct sr_channel_group));
 107                 cg->name = g_strdup(channel_names[i]);
 108                 cg->channels = g_slist_append(cg->channels, ch);
 109                 sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
 110         }
 111
 112         devc = g_malloc0(sizeof(struct dev_context));
 113
 114         for (i = 0; i < NUM_CHANNELS; i++) {
 115                 devc->ch_enabled[i] = TRUE;
 116                 devc->voltage[i] = DEFAULT_VOLTAGE;
 117                 devc->coupling[i] = DEFAULT_COUPLING;
 118         }
 119         devc->coupling_vals = prof->coupling_vals;
 120         devc->coupling_tab_size = prof->coupling_tab_size;
 121         devc->has_coupling = prof->has_coupling;
 122
 123         devc->sample_buf = NULL;
 124         devc->sample_buf_write = 0;
 125         devc->sample_buf_size = 0;
 126
 127         devc->profile = prof;
 128         devc->dev_state = IDLE;
 129         devc->samplerate = DEFAULT_SAMPLERATE;
 130
 131         sdi->priv = devc;
 132
 133         return sdi;
 134 }
 135
 136 static int configure_channels(const struct sr_dev_inst *sdi)
 137 {
 138         struct dev_context *devc;
 139         const GSList *l;
 140         int p;
 141         struct sr_channel *ch;
 142         devc = sdi->priv;
 143
 144         g_slist_free(devc->enabled_channels);
 145         devc->enabled_channels = NULL;
 146         memset(devc->ch_enabled, 0, sizeof(devc->ch_enabled));
 147
 148         for (l = sdi->channels, p = 0; l; l = l->next, p++) {
 149                 ch = l->data;
 150                 if (p < NUM_CHANNELS) {
 151                         devc->ch_enabled[p] = ch->enabled;
 152                         devc->enabled_channels = g_slist_append(devc->enabled_channels, ch);
 153                 }
 154         }
 155
 156         return SR_OK;
 157 }
 158
 159 static void clear_helper(struct dev_context *devc)
 160 {
 161         g_slist_free(devc->enabled_channels);
 162 }
 163
 164 static int dev_clear(const struct sr_dev_driver *di)
 165 {
 166         return std_dev_clear_with_callback(di, (std_dev_clear_callback)clear_helper);
 167 }
 168
 169 static GSList *scan(struct sr_dev_driver *di, GSList *options)
 170 {
 171         struct drv_context *drvc;
 172         struct dev_context *devc;
 173         struct sr_dev_inst *sdi;
 174         struct sr_usb_dev_inst *usb;
 175         struct sr_config *src;
 176         const struct hantek_6xxx_profile *prof;
 177         GSList *l, *devices, *conn_devices;
 178         struct libusb_device_descriptor des;
 179         libusb_device **devlist;
 180         int i, j;
 181         const char *conn;
 182         char connection_id[64];
 183
 184         drvc = di->context;
 185
 186         devices = 0;
 187
 188         conn = NULL;
 189         for (l = options; l; l = l->next) {
 190                 src = l->data;
 191                 if (src->key == SR_CONF_CONN) {
 192                         conn = g_variant_get_string(src->data, NULL);
 193                         break;
 194                 }
 195         }
 196         if (conn)
 197                 conn_devices = sr_usb_find(drvc->sr_ctx->libusb_ctx, conn);
 198         else
 199                 conn_devices = NULL;
 200
 201         /* Find all Hantek 60xx devices and upload firmware to all of them. */
 202         libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
 203         for (i = 0; devlist[i]; i++) {
 204                 if (conn) {
 205                         usb = NULL;
 206                         for (l = conn_devices; l; l = l->next) {
 207                                 usb = l->data;
 208                                 if (usb->bus == libusb_get_bus_number(devlist[i])
 209                                         && usb->address == libusb_get_device_address(devlist[i]))
 210                                         break;
 211                         }
 212                         if (!l)
 213                                 /* This device matched none of the ones that
 214                                  * matched the conn specification. */
 215                                 continue;
 216                 }
 217
 218                 libusb_get_device_descriptor(devlist[i], &des);
 219
 220                 usb_get_port_path(devlist[i], connection_id, sizeof(connection_id));
 221
 222                 prof = NULL;
 223                 for (j = 0; dev_profiles[j].orig_vid; j++) {
 224                         if (des.idVendor == dev_profiles[j].orig_vid
 225                                 && des.idProduct == dev_profiles[j].orig_pid) {
 226                                 /* Device matches the pre-firmware profile. */
 227                                 prof = &dev_profiles[j];
 228                                 sr_dbg("Found a %s %s.", prof->vendor, prof->model);
 229                                 sdi = hantek_6xxx_dev_new(prof);
 230                                 sdi->connection_id = g_strdup(connection_id);
 231                                 devices = g_slist_append(devices, sdi);
 232                                 devc = sdi->priv;
 233                                 if (ezusb_upload_firmware(drvc->sr_ctx, devlist[i],
 234                                                 USB_CONFIGURATION, prof->firmware) == SR_OK)
 235                                         /* Remember when the firmware on this device was updated. */
 236                                         devc->fw_updated = g_get_monotonic_time();
 237                                 else
 238                                         sr_err("Firmware upload failed.");
 239                                 /* Dummy USB address of 0xff will get overwritten later. */
 240                                 sdi->conn = sr_usb_dev_inst_new(
 241                                                 libusb_get_bus_number(devlist[i]), 0xff, NULL);
 242                                 break;
 243                         } else if (des.idVendor == dev_profiles[j].fw_vid
 244                                 && des.idProduct == dev_profiles[j].fw_pid
 245                                 && des.bcdDevice == dev_profiles[j].fw_prod_ver) {
 246                                 /* Device matches the post-firmware profile. */
 247                                 prof = &dev_profiles[j];
 248                                 sr_dbg("Found a %s %s.", prof->vendor, prof->model);
 249                                 sdi = hantek_6xxx_dev_new(prof);
 250                                 sdi->connection_id = g_strdup(connection_id);
 251                                 sdi->status = SR_ST_INACTIVE;
 252                                 devices = g_slist_append(devices, sdi);
 253                                 sdi->inst_type = SR_INST_USB;
 254                                 sdi->conn = sr_usb_dev_inst_new(
 255                                                 libusb_get_bus_number(devlist[i]),
 256                                                 libusb_get_device_address(devlist[i]), NULL);
 257                                 break;
 258                         }
 259                 }
 260                 if (!prof)
 261                         /* Not a supported VID/PID. */
 262                         continue;
 263         }
 264         libusb_free_device_list(devlist, 1);
 265
 266         return std_scan_complete(di, devices);
 267 }
 268
 269 static int dev_open(struct sr_dev_inst *sdi)
 270 {
 271         struct dev_context *devc;
 272         struct sr_usb_dev_inst *usb;
 273         int64_t timediff_us, timediff_ms;
 274         int err;
 275
 276         devc = sdi->priv;
 277         usb = sdi->conn;
 278
 279         /*
 280          * If the firmware was recently uploaded, wait up to MAX_RENUM_DELAY_MS
 281          * for the FX2 to renumerate.
 282          */
 283         err = SR_ERR;
 284         if (devc->fw_updated > 0) {
 285                 sr_info("Waiting for device to reset.");
 286                 /* Takes >= 300ms for the FX2 to be gone from the USB bus. */
 287                 g_usleep(300 * 1000);
 288                 timediff_ms = 0;
 289                 while (timediff_ms < MAX_RENUM_DELAY_MS) {
 290                         if ((err = hantek_6xxx_open(sdi)) == SR_OK)
 291                                 break;
 292                         g_usleep(100 * 1000);
 293                         timediff_us = g_get_monotonic_time() - devc->fw_updated;
 294                         timediff_ms = timediff_us / 1000;
 295                         sr_spew("Waited %" PRIi64 " ms.", timediff_ms);
 296                 }
 297                 if (timediff_ms < MAX_RENUM_DELAY_MS)
 298                         sr_info("Device came back after %"PRIu64" ms.", timediff_ms);
 299         } else {
 300                 err = hantek_6xxx_open(sdi);
 301         }
 302
 303         if (err != SR_OK) {
 304                 sr_err("Unable to open device.");
 305                 return SR_ERR;
 306         }
 307
 308         err = libusb_claim_interface(usb->devhdl, USB_INTERFACE);
 309         if (err != 0) {
 310                 sr_err("Unable to claim interface: %s.",
 311                         libusb_error_name(err));
 312                 return SR_ERR;
 313         }
 314
 315         return SR_OK;
 316 }
 317
 318 static int dev_close(struct sr_dev_inst *sdi)
 319 {
 320         hantek_6xxx_close(sdi);
 321
 322         return SR_OK;
 323 }
 324
 325 static int config_get(uint32_t key, GVariant **data,
 326         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 327 {
 328         struct dev_context *devc;
 329         struct sr_usb_dev_inst *usb;
 330         const uint64_t *vdiv;
 331         int ch_idx;
 332
 333         switch (key) {
 334         case SR_CONF_NUM_VDIV:
 335                 *data = g_variant_new_int32(ARRAY_SIZE(vdivs));
 336                 break;
 337         }
 338
 339         if (!sdi)
 340                 return SR_ERR_ARG;
 341
 342         devc = sdi->priv;
 343         if (!cg) {
 344                 switch (key) {
 345                 case SR_CONF_SAMPLERATE:
 346                         *data = g_variant_new_uint64(devc->samplerate);
 347                         break;
 348                 case SR_CONF_LIMIT_MSEC:
 349                         *data = g_variant_new_uint64(devc->limit_msec);
 350                         break;
 351                 case SR_CONF_LIMIT_SAMPLES:
 352                         *data = g_variant_new_uint64(devc->limit_samples);
 353                         break;
 354                 case SR_CONF_CONN:
 355                         if (!sdi->conn)
 356                                 return SR_ERR_ARG;
 357                         usb = sdi->conn;
 358                         if (usb->address == 255)
 359                                 /* Device still needs to re-enumerate after firmware
 360                                  * upload, so we don't know its (future) address. */
 361                                 return SR_ERR;
 362                         *data = g_variant_new_printf("%d.%d", usb->bus, usb->address);
 363                         break;
 364                 default:
 365                         return SR_ERR_NA;
 366                 }
 367         } else {
 368                 if (sdi->channel_groups->data == cg)
 369                         ch_idx = 0;
 370                 else if (sdi->channel_groups->next->data == cg)
 371                         ch_idx = 1;
 372                 else
 373                         return SR_ERR_ARG;
 374                 switch (key) {
 375                 case SR_CONF_VDIV:
 376                         vdiv = vdivs[devc->voltage[ch_idx]];
 377                         *data = g_variant_new("(tt)", vdiv[0], vdiv[1]);
 378                         break;
 379                 case SR_CONF_COUPLING:
 380                         *data = g_variant_new_string((devc->coupling[ch_idx] \
 381                                         == COUPLING_DC) ? "DC" : "AC");
 382                         break;
 383                 }
 384         }
 385
 386         return SR_OK;
 387 }
 388
 389 static int config_set(uint32_t key, GVariant *data,
 390         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 391 {
 392         struct dev_context *devc;
 393         int ch_idx, idx;
 394
 395         devc = sdi->priv;
 396         if (!cg) {
 397                 switch (key) {
 398                 case SR_CONF_SAMPLERATE:
 399                         devc->samplerate = g_variant_get_uint64(data);
 400                         hantek_6xxx_update_samplerate(sdi);
 401                         break;
 402                 case SR_CONF_LIMIT_MSEC:
 403                         devc->limit_msec = g_variant_get_uint64(data);
 404                         break;
 405                 case SR_CONF_LIMIT_SAMPLES:
 406                         devc->limit_samples = g_variant_get_uint64(data);
 407                         break;
 408                 default:
 409                         return SR_ERR_NA;
 410                 }
 411         } else {
 412                 if (sdi->channel_groups->data == cg)
 413                         ch_idx = 0;
 414                 else if (sdi->channel_groups->next->data == cg)
 415                         ch_idx = 1;
 416                 else
 417                         return SR_ERR_ARG;
 418                 switch (key) {
 419                 case SR_CONF_VDIV:
 420                         if ((idx = std_u64_tuple_idx(data, ARRAY_AND_SIZE(vdivs))) < 0)
 421                                 return SR_ERR_ARG;
 422                         devc->voltage[ch_idx] = idx;
 423                         hantek_6xxx_update_vdiv(sdi);
 424                         break;
 425                 case SR_CONF_COUPLING:
 426                         if ((idx = std_str_idx(data, devc->coupling_vals,
 427                                                 devc->coupling_tab_size)) < 0)
 428                                 return SR_ERR_ARG;
 429                         devc->coupling[ch_idx] = idx;
 430                         break;
 431                 default:
 432                         return SR_ERR_NA;
 433                 }
 434         }
 435
 436         return SR_OK;
 437 }
 438
 439 static int config_list(uint32_t key, GVariant **data,
 440         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 441 {
 442         struct dev_context *devc;
 443
 444         devc = (sdi) ? sdi->priv : NULL;
 445
 446         if (!cg) {
 447                 switch (key) {
 448                 case SR_CONF_SCAN_OPTIONS:
 449                 case SR_CONF_DEVICE_OPTIONS:
 450                         return STD_CONFIG_LIST(key, data, sdi, cg, scanopts, drvopts, devopts);
 451                 case SR_CONF_SAMPLERATE:
 452                         *data = std_gvar_samplerates(ARRAY_AND_SIZE(samplerates));
 453                         break;
 454                 default:
 455                         return SR_ERR_NA;
 456                 }
 457         } else {
 458                 switch (key) {
 459                 case SR_CONF_DEVICE_OPTIONS:
 460                         *data = std_gvar_array_u32(ARRAY_AND_SIZE(devopts_cg));
 461                         break;
 462                 case SR_CONF_COUPLING:
 463                         *data = g_variant_new_strv(devc->coupling_vals, devc->coupling_tab_size);
 464                         break;
 465                 case SR_CONF_VDIV:
 466                         *data = std_gvar_tuple_array(ARRAY_AND_SIZE(vdivs));
 467                         break;
 468                 default:
 469                         return SR_ERR_NA;
 470                 }
 471         }
 472
 473         return SR_OK;
 474 }
 475
 476 /* Minimise data amount for limit_samples and limit_msec limits. */
 477 static uint32_t data_amount(const struct sr_dev_inst *sdi)
 478 {
 479         struct dev_context *devc = sdi->priv;
 480         uint32_t data_left, data_left_2, i;
 481         int32_t time_left;
 482
 483         if (devc->limit_msec) {
 484                 time_left = devc->limit_msec - (g_get_monotonic_time() - devc->aq_started) / 1000;
 485                 data_left = devc->samplerate * MAX(time_left, 0) * NUM_CHANNELS / 1000;
 486         } else if (devc->limit_samples) {
 487                 data_left = (devc->limit_samples - devc->samp_received) * NUM_CHANNELS;
 488         } else {
 489                 data_left = devc->samplerate * NUM_CHANNELS;
 490         }
 491
 492         /* Round up to nearest power of two. */
 493         for (i = MIN_PACKET_SIZE; i < data_left; i *= 2)
 494                 ;
 495         data_left_2 = i;
 496
 497         sr_spew("data_amount: %u (rounded to power of 2: %u)", data_left, data_left_2);
 498
 499         return data_left_2;
 500 }
 501
 502 static void send_chunk(struct sr_dev_inst *sdi, unsigned char *buf,
 503                 int num_samples)
 504 {
 505         struct sr_datafeed_packet packet;
 506         struct sr_datafeed_analog analog;
 507         struct sr_analog_encoding encoding;
 508         struct sr_analog_meaning meaning;
 509         struct sr_analog_spec spec;
 510         struct dev_context *devc = sdi->priv;
 511         GSList *channels = devc->enabled_channels;
 512
 513         const float ch_bit[] = { RANGE(0) / 255, RANGE(1) / 255 };
 514         const float ch_center[] = { RANGE(0) / 2, RANGE(1) / 2 };
 515
 516         sr_analog_init(&analog, &encoding, &meaning, &spec, 0);
 517
 518         packet.type = SR_DF_ANALOG;
 519         packet.payload = &analog;
 520
 521         analog.num_samples = num_samples;
 522         analog.meaning->mq = SR_MQ_VOLTAGE;
 523         analog.meaning->unit = SR_UNIT_VOLT;
 524         analog.meaning->mqflags = 0;
 525
 526         analog.data = g_try_malloc(num_samples * sizeof(float));
 527         if (!analog.data) {
 528                 sr_err("Analog data buffer malloc failed.");
 529                 devc->dev_state = STOPPING;
 530                 return;
 531         }
 532
 533         for (int ch = 0; ch < 2; ch++) {
 534                 if (!devc->ch_enabled[ch])
 535                         continue;
 536
 537                 float vdivlog = log10f(ch_bit[ch]);
 538                 int digits = -(int)vdivlog + (vdivlog < 0.0);
 539                 analog.encoding->digits = digits;
 540                 analog.spec->spec_digits = digits;
 541                 analog.meaning->channels = g_slist_append(NULL, channels->data);
 542
 543                 for (int i = 0; i < num_samples; i++) {
 544                         /*
 545                          * The device always sends data for both channels. If a channel
 546                          * is disabled, it contains a copy of the enabled channel's
 547                          * data. However, we only send the requested channels to
 548                          * the bus.
 549                          *
 550                          * Voltage values are encoded as a value 0-255, where the
 551                          * value is a point in the range represented by the vdiv
 552                          * setting. There are 10 vertical divs, so e.g. 500mV/div
 553                          * represents 5V peak-to-peak where 0 = -2.5V and 255 = +2.5V.
 554                          */
 555                         ((float *)analog.data)[i] = ch_bit[ch] * *(buf + i * 2 + ch) - ch_center[ch];
 556                 }
 557
 558                 sr_session_send(sdi, &packet);
 559                 g_slist_free(analog.meaning->channels);
 560
 561                 channels = channels->next;
 562         }
 563         g_free(analog.data);
 564 }
 565
 566 static void send_data(struct sr_dev_inst *sdi, struct libusb_transfer *buf[], uint64_t samples)
 567 {
 568         int i = 0;
 569         uint64_t send = 0;
 570         uint32_t chunk;
 571
 572         while (send < samples) {
 573                 chunk = MIN(samples - send, (uint64_t)(buf[i]->actual_length / NUM_CHANNELS));
 574                 send += chunk;
 575                 send_chunk(sdi, buf[i]->buffer, chunk);
 576
 577                 /*
 578                  * Everything in this transfer was either copied to the buffer
 579                  * or sent to the session bus.
 580                  */
 581                 g_free(buf[i]->buffer);
 582                 libusb_free_transfer(buf[i]);
 583                 i++;
 584         }
 585 }
 586
 587 /*
 588  * Called by libusb (as triggered by handle_event()) when a transfer comes in.
 589  * Only channel data comes in asynchronously, and all transfers for this are
 590  * queued up beforehand, so this just needs to chuck the incoming data onto
 591  * the libsigrok session bus.
 592  */
 593 static void LIBUSB_CALL receive_transfer(struct libusb_transfer *transfer)
 594 {
 595         struct sr_dev_inst *sdi;
 596         struct dev_context *devc;
 597
 598         sdi = transfer->user_data;
 599         devc = sdi->priv;
 600
 601         if (devc->dev_state == FLUSH) {
 602                 g_free(transfer->buffer);
 603                 libusb_free_transfer(transfer);
 604                 devc->dev_state = CAPTURE;
 605                 devc->aq_started = g_get_monotonic_time();
 606                 read_channel(sdi, data_amount(sdi));
 607                 return;
 608         }
 609
 610         if (devc->dev_state != CAPTURE)
 611                 return;
 612
 613         if (!devc->sample_buf) {
 614                 devc->sample_buf_size = 10;
 615                 devc->sample_buf = g_try_malloc(devc->sample_buf_size * sizeof(transfer));
 616                 devc->sample_buf_write = 0;
 617         }
 618
 619         if (devc->sample_buf_write >= devc->sample_buf_size) {
 620                 devc->sample_buf_size += 10;
 621                 devc->sample_buf = g_try_realloc(devc->sample_buf,
 622                                 devc->sample_buf_size * sizeof(transfer));
 623                 if (!devc->sample_buf) {
 624                         sr_err("Sample buffer malloc failed.");
 625                         devc->dev_state = STOPPING;
 626                         return;
 627                 }
 628         }
 629
 630         devc->sample_buf[devc->sample_buf_write++] = transfer;
 631         devc->samp_received += transfer->actual_length / NUM_CHANNELS;
 632
 633         sr_spew("receive_transfer(): calculated samplerate == %" PRIu64 "ks/s",
 634                 (uint64_t)(transfer->actual_length * 1000 /
 635                 (g_get_monotonic_time() - devc->read_start_ts + 1) /
 636                 NUM_CHANNELS));
 637
 638         sr_spew("receive_transfer(): status %s received %d bytes.",
 639                 libusb_error_name(transfer->status), transfer->actual_length);
 640
 641         if (transfer->actual_length == 0)
 642                 /* Nothing to send to the bus. */
 643                 return;
 644
 645         if (devc->limit_samples && devc->samp_received >= devc->limit_samples) {
 646                 sr_info("Requested number of samples reached, stopping. %"
 647                         PRIu64 " <= %" PRIu64, devc->limit_samples,
 648                         devc->samp_received);
 649                 send_data(sdi, devc->sample_buf, devc->limit_samples);
 650                 sr_dev_acquisition_stop(sdi);
 651         } else if (devc->limit_msec && (g_get_monotonic_time() -
 652                         devc->aq_started) / 1000 >= devc->limit_msec) {
 653                 sr_info("Requested time limit reached, stopping. %d <= %d",
 654                         (uint32_t)devc->limit_msec,
 655                         (uint32_t)(g_get_monotonic_time() - devc->aq_started) / 1000);
 656                 send_data(sdi, devc->sample_buf, devc->samp_received);
 657                 g_free(devc->sample_buf);
 658                 devc->sample_buf = NULL;
 659                 sr_dev_acquisition_stop(sdi);
 660         } else {
 661                 read_channel(sdi, data_amount(sdi));
 662         }
 663 }
 664
 665 static int read_channel(const struct sr_dev_inst *sdi, uint32_t amount)
 666 {
 667         int ret;
 668         struct dev_context *devc;
 669
 670         devc = sdi->priv;
 671
 672         amount = MIN(amount, MAX_PACKET_SIZE);
 673         ret = hantek_6xxx_get_channeldata(sdi, receive_transfer, amount);
 674         devc->read_start_ts = g_get_monotonic_time();
 675         devc->read_data_amount = amount;
 676
 677         return ret;
 678 }
 679
 680 static int handle_event(int fd, int revents, void *cb_data)
 681 {
 682         const struct sr_dev_inst *sdi;
 683         struct timeval tv;
 684         struct sr_dev_driver *di;
 685         struct dev_context *devc;
 686         struct drv_context *drvc;
 687
 688         (void)fd;
 689         (void)revents;
 690
 691         sdi = cb_data;
 692         di = sdi->driver;
 693         drvc = di->context;
 694         devc = sdi->priv;
 695
 696         /* Always handle pending libusb events. */
 697         tv.tv_sec = tv.tv_usec = 0;
 698         libusb_handle_events_timeout(drvc->sr_ctx->libusb_ctx, &tv);
 699
 700         if (devc->dev_state == STOPPING) {
 701                 /* We've been told to wind up the acquisition. */
 702                 sr_dbg("Stopping acquisition.");
 703
 704                 hantek_6xxx_stop_data_collecting(sdi);
 705                 /*
 706                  * TODO: Doesn't really cancel pending transfers so they might
 707                  * come in after SR_DF_END is sent.
 708                  */
 709                 usb_source_remove(sdi->session, drvc->sr_ctx);
 710
 711                 std_session_send_df_end(sdi);
 712
 713                 devc->dev_state = IDLE;
 714
 715                 return TRUE;
 716         }
 717
 718         return TRUE;
 719 }
 720
 721 static int dev_acquisition_start(const struct sr_dev_inst *sdi)
 722 {
 723         struct dev_context *devc;
 724         struct sr_dev_driver *di = sdi->driver;
 725         struct drv_context *drvc = di->context;
 726
 727         devc = sdi->priv;
 728
 729         if (configure_channels(sdi) != SR_OK) {
 730                 sr_err("Failed to configure channels.");
 731                 return SR_ERR;
 732         }
 733
 734         if (hantek_6xxx_init(sdi) != SR_OK)
 735                 return SR_ERR;
 736
 737         std_session_send_df_header(sdi);
 738
 739         devc->samp_received = 0;
 740         devc->dev_state = FLUSH;
 741
 742         usb_source_add(sdi->session, drvc->sr_ctx, TICK,
 743                        handle_event, (void *)sdi);
 744
 745         hantek_6xxx_start_data_collecting(sdi);
 746
 747         read_channel(sdi, FLUSH_PACKET_SIZE);
 748
 749         return SR_OK;
 750 }
 751
 752 static int dev_acquisition_stop(struct sr_dev_inst *sdi)
 753 {
 754         struct dev_context *devc;
 755
 756         devc = sdi->priv;
 757         devc->dev_state = STOPPING;
 758
 759         g_free(devc->sample_buf);
 760         devc->sample_buf = NULL;
 761
 762         return SR_OK;
 763 }
 764
 765 static struct sr_dev_driver hantek_6xxx_driver_info = {
 766         .name = "hantek-6xxx",
 767         .longname = "Hantek 6xxx",
 768         .api_version = 1,
 769         .init = std_init,
 770         .cleanup = std_cleanup,
 771         .scan = scan,
 772         .dev_list = std_dev_list,
 773         .dev_clear = dev_clear,
 774         .config_get = config_get,
 775         .config_set = config_set,
 776         .config_list = config_list,
 777         .dev_open = dev_open,
 778         .dev_close = dev_close,
 779         .dev_acquisition_start = dev_acquisition_start,
 780         .dev_acquisition_stop = dev_acquisition_stop,
 781         .context = NULL,
 782 };
 783 SR_REGISTER_DEV_DRIVER(hantek_6xxx_driver_info);