hardware/victor-dmm/api.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2012 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 <glib.h>
  21 #include <libusb.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include "libsigrok.h"
  25 #include "libsigrok-internal.h"
  26 #include "protocol.h"
  27
  28 #define VICTOR_VID 0x1244
  29 #define VICTOR_PID 0xd237
  30 #define VICTOR_VENDOR "Victor"
  31 #define VICTOR_INTERFACE 0
  32 #define VICTOR_ENDPOINT LIBUSB_ENDPOINT_IN | 1
  33
  34 SR_PRIV struct sr_dev_driver victor_dmm_driver_info;
  35 static struct sr_dev_driver *di = &victor_dmm_driver_info;
  36 static int hw_dev_close(struct sr_dev_inst *sdi);
  37 static int hw_dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data);
  38
  39 static const int hwcaps[] = {
  40         SR_HWCAP_MULTIMETER,
  41         SR_HWCAP_LIMIT_MSEC,
  42         SR_HWCAP_LIMIT_SAMPLES,
  43         SR_HWCAP_CONTINUOUS,
  44         0
  45 };
  46
  47 /* Properly close and free all devices. */
  48 static int clear_instances(void)
  49 {
  50         struct sr_dev_inst *sdi;
  51         struct drv_context *drvc;
  52         struct dev_context *devc;
  53         GSList *l;
  54
  55         if (!(drvc = di->priv))
  56                 /* Can get called on an unused driver, doesn't matter. */
  57                 return SR_OK;
  58
  59         for (l = drvc->instances; l; l = l->next) {
  60                 if (!(sdi = l->data))
  61                         continue;
  62                 if (!(devc = sdi->priv))
  63                         continue;
  64                 hw_dev_close(sdi);
  65                 sr_usb_dev_inst_free(devc->usb);
  66                 sr_dev_inst_free(sdi);
  67         }
  68
  69         g_slist_free(drvc->instances);
  70         drvc->instances = NULL;
  71
  72         return SR_OK;
  73 }
  74
  75 static int hw_init(struct sr_context *sr_ctx)
  76 {
  77         struct drv_context *drvc;
  78
  79         if (!(drvc = g_try_malloc0(sizeof(struct drv_context)))) {
  80                 sr_err("Driver context malloc failed.");
  81                 return SR_ERR_MALLOC;
  82         }
  83         drvc->sr_ctx = sr_ctx;
  84         di->priv = drvc;
  85
  86         return SR_OK;
  87 }
  88
  89 static GSList *hw_scan(GSList *options)
  90 {
  91         struct drv_context *drvc;
  92         struct dev_context *devc;
  93         struct sr_dev_inst *sdi;
  94         struct sr_probe *probe;
  95         struct libusb_device_descriptor des;
  96         libusb_device **devlist;
  97         GSList *devices;
  98         int ret, devcnt, i;
  99
 100         (void)options;
 101
 102         if (!(drvc = di->priv)) {
 103                 sr_err("Driver was not initialized.");
 104                 return NULL;
 105         }
 106
 107         /* USB scan is always authoritative. */
 108         clear_instances();
 109
 110         devices = NULL;
 111         libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
 112         for (i = 0; devlist[i]; i++) {
 113                 if ((ret = libusb_get_device_descriptor(devlist[i], &des)) != 0) {
 114                         sr_warn("Failed to get device descriptor: %s",
 115                                         libusb_error_name(ret));
 116                         continue;
 117                 }
 118
 119                 if (des.idVendor != VICTOR_VID || des.idProduct != VICTOR_PID)
 120                         continue;
 121
 122                 devcnt = g_slist_length(drvc->instances);
 123                 if (!(sdi = sr_dev_inst_new(devcnt, SR_ST_INACTIVE,
 124                                 VICTOR_VENDOR, NULL, NULL)))
 125                         return NULL;
 126                 sdi->driver = di;
 127
 128                 if (!(devc = g_try_malloc0(sizeof(struct dev_context))))
 129                         return NULL;
 130                 sdi->priv = devc;
 131
 132                 if (!(probe = sr_probe_new(0, SR_PROBE_ANALOG, TRUE, "P1")))
 133                         return NULL;
 134                 sdi->probes = g_slist_append(NULL, probe);
 135
 136                 if (!(devc->usb = sr_usb_dev_inst_new(libusb_get_bus_number(devlist[i]),
 137                                 libusb_get_device_address(devlist[i]), NULL)))
 138                         return NULL;
 139
 140                 drvc->instances = g_slist_append(drvc->instances, sdi);
 141                 devices = g_slist_append(devices, sdi);
 142         }
 143         libusb_free_device_list(devlist, 1);
 144
 145         return devices;
 146 }
 147
 148 static GSList *hw_dev_list(void)
 149 {
 150         struct drv_context *drvc;
 151
 152         if (!(drvc = di->priv)) {
 153                 sr_err("Driver was not initialized.");
 154                 return NULL;
 155         }
 156
 157         return drvc->instances;
 158 }
 159
 160 static int hw_dev_open(struct sr_dev_inst *sdi)
 161 {
 162         struct dev_context *devc;
 163         struct drv_context *drvc = di->priv;
 164         libusb_device **devlist;
 165         int ret, i;
 166
 167         if (!di->priv) {
 168                 sr_err("Driver was not initialized.");
 169                 return SR_ERR;
 170         }
 171
 172         devc = sdi->priv;
 173         libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
 174         for (i = 0; devlist[i]; i++) {
 175                 if (libusb_get_bus_number(devlist[i]) != devc->usb->bus
 176                                 || libusb_get_device_address(devlist[i]) != devc->usb->address)
 177                         continue;
 178                 if ((ret = libusb_open(devlist[i], &devc->usb->devhdl))) {
 179                         sr_err("Failed to open device: %s.", libusb_error_name(ret));
 180                         return SR_ERR;
 181                 }
 182                 break;
 183         }
 184         libusb_free_device_list(devlist, 1);
 185         if (!devlist[i]) {
 186                 sr_err("Device not found.");
 187                 return SR_ERR;
 188         }
 189
 190         /* The device reports as HID class, so the kernel would have
 191          * claimed it. */
 192         if (libusb_kernel_driver_active(devc->usb->devhdl, 0) == 1) {
 193                 if ((ret = libusb_detach_kernel_driver(devc->usb->devhdl, 0)) < 0) {
 194                         sr_err("Failed to detach kernel driver: %s.",
 195                                libusb_error_name(ret));
 196                         return SR_ERR;
 197                 }
 198         }
 199
 200         if ((ret = libusb_claim_interface(devc->usb->devhdl,
 201                         VICTOR_INTERFACE))) {
 202                 sr_err("Failed to claim interface: %s.", libusb_error_name(ret));
 203                 return SR_ERR;
 204         }
 205         sdi->status = SR_ST_ACTIVE;
 206
 207         return SR_OK;
 208 }
 209
 210 static int hw_dev_close(struct sr_dev_inst *sdi)
 211 {
 212         struct dev_context *devc;
 213
 214         if (!di->priv) {
 215                 sr_err("Driver was not initialized.");
 216                 return SR_ERR;
 217         }
 218
 219         devc = sdi->priv;
 220         if (!devc->usb->devhdl)
 221                 /*  Nothing to do. */
 222                 return SR_OK;
 223
 224         libusb_release_interface(devc->usb->devhdl, VICTOR_INTERFACE);
 225         libusb_close(devc->usb->devhdl);
 226         devc->usb->devhdl = NULL;
 227         sdi->status = SR_ST_INACTIVE;
 228
 229         return SR_OK;
 230 }
 231
 232 static int hw_cleanup(void)
 233 {
 234         struct drv_context *drvc;
 235
 236         if (!(drvc = di->priv))
 237                 /* Can get called on an unused driver, doesn't matter. */
 238                 return SR_OK;
 239
 240         clear_instances();
 241         g_free(drvc);
 242         di->priv = NULL;
 243
 244         return SR_OK;
 245 }
 246
 247 static int hw_info_get(int info_id, const void **data,
 248                        const struct sr_dev_inst *sdi)
 249 {
 250         (void)sdi;
 251
 252         switch (info_id) {
 253         case SR_DI_HWCAPS:
 254                 *data = hwcaps;
 255                 break;
 256         default:
 257                 sr_err("Unknown info_id: %d.", info_id);
 258                 return SR_ERR_ARG;
 259         }
 260
 261         return SR_OK;
 262 }
 263
 264 static int hw_dev_config_set(const struct sr_dev_inst *sdi, int hwcap,
 265                              const void *value)
 266 {
 267         struct dev_context *devc;
 268         gint64 now;
 269         int ret;
 270
 271         if (!di->priv) {
 272                 sr_err("Driver was not initialized.");
 273                 return SR_ERR;
 274         }
 275
 276         if (sdi->status != SR_ST_ACTIVE) {
 277                 sr_err("Device inactive, can't set config options.");
 278                 return SR_ERR;
 279         }
 280
 281         devc = sdi->priv;
 282         ret = SR_OK;
 283         switch (hwcap) {
 284         case SR_HWCAP_LIMIT_MSEC:
 285                 devc->limit_msec = *(const int64_t *)value;
 286                 now = g_get_monotonic_time() / 1000;
 287                 devc->end_time = now + devc->limit_msec;
 288                 sr_dbg("Setting time limit to %" PRIu64 "ms.",
 289                        devc->limit_msec);
 290                 break;
 291         case SR_HWCAP_LIMIT_SAMPLES:
 292                 devc->limit_samples = *(const uint64_t *)value;
 293                 sr_dbg("Setting sample limit to %" PRIu64 ".",
 294                        devc->limit_samples);
 295                 break;
 296         default:
 297                 sr_err("Unknown hardware capability: %d.", hwcap);
 298                 ret = SR_ERR_ARG;
 299         }
 300
 301         return ret;
 302 }
 303
 304 static void receive_transfer(struct libusb_transfer *transfer)
 305 {
 306         struct dev_context *devc;
 307         struct sr_dev_inst *sdi;
 308         int ret;
 309
 310         sdi = transfer->user_data;
 311         devc = sdi->priv;
 312         if (transfer->status == LIBUSB_TRANSFER_NO_DEVICE) {
 313                 /* USB device was unplugged. */
 314                 hw_dev_acquisition_stop(sdi, sdi);
 315         } else if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
 316                 sr_dbg("Got %d-byte packet.", transfer->actual_length);
 317                 if (transfer->actual_length == DMM_DATA_SIZE) {
 318                         victor_dmm_receive_data(sdi, transfer->buffer);
 319                         if (devc->limit_samples) {
 320                                 if (devc->num_samples >= devc->limit_samples)
 321                                         hw_dev_acquisition_stop(sdi, sdi);
 322                         }
 323                 }
 324         }
 325         /* Anything else is either an error or a timeout, which is fine:
 326          * we were just going to send another transfer request anyway. */
 327
 328         if (sdi->status == SR_ST_ACTIVE) {
 329                 /* Send the same request again. */
 330                 if ((ret = libusb_submit_transfer(transfer) != 0)) {
 331                         sr_err("Unable to resubmit transfer: %s.",
 332                                libusb_error_name(ret));
 333                         g_free(transfer->buffer);
 334                         libusb_free_transfer(transfer);
 335                         hw_dev_acquisition_stop(sdi, sdi);
 336                 }
 337         } else {
 338                 /* This was the last transfer we're going to receive, so
 339                  * clean up now. */
 340                 g_free(transfer->buffer);
 341                 libusb_free_transfer(transfer);
 342         }
 343 }
 344
 345 static int handle_events(int fd, int revents, void *cb_data)
 346 {
 347         struct dev_context *devc;
 348         struct drv_context *drvc = di->priv;
 349         struct sr_datafeed_packet packet;
 350         struct sr_dev_inst *sdi;
 351         struct timeval tv;
 352         gint64 now;
 353         int i;
 354
 355         (void)fd;
 356         (void)revents;
 357
 358         sdi = cb_data;
 359         devc = sdi->priv;
 360
 361         if (devc->limit_msec) {
 362                 now = g_get_monotonic_time() / 1000;
 363                 if (now > devc->end_time)
 364                         hw_dev_acquisition_stop(sdi, sdi);
 365         }
 366
 367         if (sdi->status == SR_ST_STOPPING) {
 368                 for (i = 0; devc->usbfd[i] != -1; i++)
 369                         sr_source_remove(devc->usbfd[i]);
 370
 371                 hw_dev_close(sdi);
 372
 373                 packet.type = SR_DF_END;
 374                 sr_session_send(cb_data, &packet);
 375         }
 376
 377         memset(&tv, 0, sizeof(struct timeval));
 378         libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx, &tv,
 379                                                NULL);
 380
 381         return TRUE;
 382 }
 383
 384 static int hw_dev_acquisition_start(const struct sr_dev_inst *sdi,
 385                                     void *cb_data)
 386 {
 387         struct sr_datafeed_packet packet;
 388         struct sr_datafeed_header header;
 389         struct sr_datafeed_meta_analog meta;
 390         struct dev_context *devc;
 391         struct drv_context *drvc = di->priv;
 392         const struct libusb_pollfd **pfd;
 393         struct libusb_transfer *transfer;
 394         int ret, i;
 395         unsigned char *buf;
 396
 397         if (!di->priv) {
 398                 sr_err("Driver was not initialized.");
 399                 return SR_ERR;
 400         }
 401
 402         sr_dbg("Starting acquisition.");
 403
 404         devc = sdi->priv;
 405         devc->cb_data = cb_data;
 406
 407         /* Send header packet to the session bus. */
 408         sr_dbg("Sending SR_DF_HEADER.");
 409         packet.type = SR_DF_HEADER;
 410         packet.payload = (uint8_t *)&header;
 411         header.feed_version = 1;
 412         sr_session_send(devc->cb_data, &packet);
 413
 414         /* Send metadata about the SR_DF_ANALOG packets to come. */
 415         packet.type = SR_DF_META_ANALOG;
 416         packet.payload = &meta;
 417         meta.num_probes = 1;
 418         sr_session_send(devc->cb_data, &packet);
 419
 420         pfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
 421         for (i = 0; pfd[i]; i++) {
 422                 /* Handle USB events every 100ms, for decent latency. */
 423                 sr_source_add(pfd[i]->fd, pfd[i]->events, 100,
 424                                 handle_events, (void *)sdi);
 425                 /* We'll need to remove this fd later. */
 426                 devc->usbfd[i] = pfd[i]->fd;
 427         }
 428         devc->usbfd[i] = -1;
 429
 430         buf = g_try_malloc(DMM_DATA_SIZE);
 431         transfer = libusb_alloc_transfer(0);
 432         /* Each transfer request gets 100ms to arrive before it's restarted.
 433          * The device only sends 1 transfer/second no matter how many
 434          * times you ask, but we want to keep step with the USB events
 435          * handling above. */
 436         libusb_fill_interrupt_transfer(transfer, devc->usb->devhdl,
 437                         VICTOR_ENDPOINT, buf, DMM_DATA_SIZE, receive_transfer,
 438                         cb_data, 100);
 439         if ((ret = libusb_submit_transfer(transfer) != 0)) {
 440                 sr_err("Unable to submit transfer: %s.", libusb_error_name(ret));
 441                 libusb_free_transfer(transfer);
 442                 g_free(buf);
 443                 return SR_ERR;
 444         }
 445
 446         return SR_OK;
 447 }
 448
 449 static int hw_dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
 450 {
 451         (void)cb_data;
 452
 453         if (!di->priv) {
 454                 sr_err("Driver was not initialized.");
 455                 return SR_ERR;
 456         }
 457
 458         if (sdi->status != SR_ST_ACTIVE) {
 459                 sr_err("Device not active, can't stop acquisition.");
 460                 return SR_ERR;
 461         }
 462
 463         sdi->status = SR_ST_STOPPING;
 464
 465         return SR_OK;
 466 }
 467
 468 SR_PRIV struct sr_dev_driver victor_dmm_driver_info = {
 469         .name = "victor-dmm",
 470         .longname = "Victor DMMs",
 471         .api_version = 1,
 472         .init = hw_init,
 473         .cleanup = hw_cleanup,
 474         .scan = hw_scan,
 475         .dev_list = hw_dev_list,
 476         .dev_clear = clear_instances,
 477         .dev_open = hw_dev_open,
 478         .dev_close = hw_dev_close,
 479         .info_get = hw_info_get,
 480         .dev_config_set = hw_dev_config_set,
 481         .dev_acquisition_start = hw_dev_acquisition_start,
 482         .dev_acquisition_stop = hw_dev_acquisition_stop,
 483         .priv = NULL,
 484 };