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_CONF_MULTIMETER,
  41         SR_CONF_LIMIT_MSEC,
  42         SR_CONF_LIMIT_SAMPLES,
  43         SR_CONF_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 config_get(int id, const void **data, const struct sr_dev_inst *sdi)
 248 {
 249         (void)sdi;
 250
 251         switch (id) {
 252         case SR_DI_HWCAPS:
 253                 *data = hwcaps;
 254                 break;
 255         default:
 256                 return SR_ERR_ARG;
 257         }
 258
 259         return SR_OK;
 260 }
 261
 262 static int config_set(int id, const void *value, const struct sr_dev_inst *sdi)
 263 {
 264         struct dev_context *devc;
 265         gint64 now;
 266         int ret;
 267
 268         if (!di->priv) {
 269                 sr_err("Driver was not initialized.");
 270                 return SR_ERR;
 271         }
 272
 273         if (sdi->status != SR_ST_ACTIVE) {
 274                 sr_err("Device inactive, can't set config options.");
 275                 return SR_ERR;
 276         }
 277
 278         devc = sdi->priv;
 279         ret = SR_OK;
 280         switch (id) {
 281         case SR_CONF_LIMIT_MSEC:
 282                 devc->limit_msec = *(const int64_t *)value;
 283                 now = g_get_monotonic_time() / 1000;
 284                 devc->end_time = now + devc->limit_msec;
 285                 sr_dbg("Setting time limit to %" PRIu64 "ms.",
 286                        devc->limit_msec);
 287                 break;
 288         case SR_CONF_LIMIT_SAMPLES:
 289                 devc->limit_samples = *(const uint64_t *)value;
 290                 sr_dbg("Setting sample limit to %" PRIu64 ".",
 291                        devc->limit_samples);
 292                 break;
 293         default:
 294                 sr_err("Unknown hardware capability: %d.", id);
 295                 ret = SR_ERR_ARG;
 296         }
 297
 298         return ret;
 299 }
 300
 301 static void receive_transfer(struct libusb_transfer *transfer)
 302 {
 303         struct dev_context *devc;
 304         struct sr_dev_inst *sdi;
 305         int ret;
 306
 307         sdi = transfer->user_data;
 308         devc = sdi->priv;
 309         if (transfer->status == LIBUSB_TRANSFER_NO_DEVICE) {
 310                 /* USB device was unplugged. */
 311                 hw_dev_acquisition_stop(sdi, sdi);
 312         } else if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
 313                 sr_dbg("Got %d-byte packet.", transfer->actual_length);
 314                 if (transfer->actual_length == DMM_DATA_SIZE) {
 315                         victor_dmm_receive_data(sdi, transfer->buffer);
 316                         if (devc->limit_samples) {
 317                                 if (devc->num_samples >= devc->limit_samples)
 318                                         hw_dev_acquisition_stop(sdi, sdi);
 319                         }
 320                 }
 321         }
 322         /* Anything else is either an error or a timeout, which is fine:
 323          * we were just going to send another transfer request anyway. */
 324
 325         if (sdi->status == SR_ST_ACTIVE) {
 326                 /* Send the same request again. */
 327                 if ((ret = libusb_submit_transfer(transfer) != 0)) {
 328                         sr_err("Unable to resubmit transfer: %s.",
 329                                libusb_error_name(ret));
 330                         g_free(transfer->buffer);
 331                         libusb_free_transfer(transfer);
 332                         hw_dev_acquisition_stop(sdi, sdi);
 333                 }
 334         } else {
 335                 /* This was the last transfer we're going to receive, so
 336                  * clean up now. */
 337                 g_free(transfer->buffer);
 338                 libusb_free_transfer(transfer);
 339         }
 340 }
 341
 342 static int handle_events(int fd, int revents, void *cb_data)
 343 {
 344         struct dev_context *devc;
 345         struct drv_context *drvc = di->priv;
 346         struct sr_datafeed_packet packet;
 347         struct sr_dev_inst *sdi;
 348         struct timeval tv;
 349         gint64 now;
 350         int i;
 351
 352         (void)fd;
 353         (void)revents;
 354
 355         sdi = cb_data;
 356         devc = sdi->priv;
 357
 358         if (devc->limit_msec) {
 359                 now = g_get_monotonic_time() / 1000;
 360                 if (now > devc->end_time)
 361                         hw_dev_acquisition_stop(sdi, sdi);
 362         }
 363
 364         if (sdi->status == SR_ST_STOPPING) {
 365                 for (i = 0; devc->usbfd[i] != -1; i++)
 366                         sr_source_remove(devc->usbfd[i]);
 367
 368                 hw_dev_close(sdi);
 369
 370                 packet.type = SR_DF_END;
 371                 sr_session_send(cb_data, &packet);
 372         }
 373
 374         memset(&tv, 0, sizeof(struct timeval));
 375         libusb_handle_events_timeout_completed(drvc->sr_ctx->libusb_ctx, &tv,
 376                                                NULL);
 377
 378         return TRUE;
 379 }
 380
 381 static int hw_dev_acquisition_start(const struct sr_dev_inst *sdi,
 382                                     void *cb_data)
 383 {
 384         struct sr_datafeed_packet packet;
 385         struct sr_datafeed_header header;
 386         struct dev_context *devc;
 387         struct drv_context *drvc = di->priv;
 388         const struct libusb_pollfd **pfd;
 389         struct libusb_transfer *transfer;
 390         int ret, i;
 391         unsigned char *buf;
 392
 393         if (!di->priv) {
 394                 sr_err("Driver was not initialized.");
 395                 return SR_ERR;
 396         }
 397
 398         sr_dbg("Starting acquisition.");
 399
 400         devc = sdi->priv;
 401         devc->cb_data = cb_data;
 402
 403         /* Send header packet to the session bus. */
 404         sr_dbg("Sending SR_DF_HEADER.");
 405         packet.type = SR_DF_HEADER;
 406         packet.payload = (uint8_t *)&header;
 407         header.feed_version = 1;
 408         sr_session_send(devc->cb_data, &packet);
 409
 410         pfd = libusb_get_pollfds(drvc->sr_ctx->libusb_ctx);
 411         for (i = 0; pfd[i]; i++) {
 412                 /* Handle USB events every 100ms, for decent latency. */
 413                 sr_source_add(pfd[i]->fd, pfd[i]->events, 100,
 414                                 handle_events, (void *)sdi);
 415                 /* We'll need to remove this fd later. */
 416                 devc->usbfd[i] = pfd[i]->fd;
 417         }
 418         devc->usbfd[i] = -1;
 419
 420         buf = g_try_malloc(DMM_DATA_SIZE);
 421         transfer = libusb_alloc_transfer(0);
 422         /* Each transfer request gets 100ms to arrive before it's restarted.
 423          * The device only sends 1 transfer/second no matter how many
 424          * times you ask, but we want to keep step with the USB events
 425          * handling above. */
 426         libusb_fill_interrupt_transfer(transfer, devc->usb->devhdl,
 427                         VICTOR_ENDPOINT, buf, DMM_DATA_SIZE, receive_transfer,
 428                         cb_data, 100);
 429         if ((ret = libusb_submit_transfer(transfer) != 0)) {
 430                 sr_err("Unable to submit transfer: %s.", libusb_error_name(ret));
 431                 libusb_free_transfer(transfer);
 432                 g_free(buf);
 433                 return SR_ERR;
 434         }
 435
 436         return SR_OK;
 437 }
 438
 439 static int hw_dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
 440 {
 441         (void)cb_data;
 442
 443         if (!di->priv) {
 444                 sr_err("Driver was not initialized.");
 445                 return SR_ERR;
 446         }
 447
 448         if (sdi->status != SR_ST_ACTIVE) {
 449                 sr_err("Device not active, can't stop acquisition.");
 450                 return SR_ERR;
 451         }
 452
 453         sdi->status = SR_ST_STOPPING;
 454
 455         return SR_OK;
 456 }
 457
 458 SR_PRIV struct sr_dev_driver victor_dmm_driver_info = {
 459         .name = "victor-dmm",
 460         .longname = "Victor DMMs",
 461         .api_version = 1,
 462         .init = hw_init,
 463         .cleanup = hw_cleanup,
 464         .scan = hw_scan,
 465         .dev_list = hw_dev_list,
 466         .dev_clear = clear_instances,
 467         .config_get = config_get,
 468         .config_set = config_set,
 469         .dev_open = hw_dev_open,
 470         .dev_close = hw_dev_close,
 471         .dev_acquisition_start = hw_dev_acquisition_start,
 472         .dev_acquisition_stop = hw_dev_acquisition_stop,
 473         .priv = NULL,
 474 };