hardware/radioshack-dmm/api.c

   1 /*
   2  * This file is part of the sigrok project.
   3  *
   4  * Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
   5  * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <glib.h>
  22 #include "libsigrok.h"
  23 #include "libsigrok-internal.h"
  24 #include "radioshack-dmm.h"
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <fcntl.h>
  28 #include <string.h>
  29 #include <errno.h>
  30
  31 static const int hwopts[] = {
  32         SR_HWOPT_CONN,
  33         SR_HWOPT_SERIALCOMM,
  34         0,
  35 };
  36
  37 static const int hwcaps[] = {
  38         SR_HWCAP_MULTIMETER,
  39         SR_HWCAP_LIMIT_SAMPLES,
  40         SR_HWCAP_CONTINUOUS,
  41         0,
  42 };
  43
  44 static const char *probe_names[] = {
  45         "Probe",
  46         NULL,
  47 };
  48
  49 SR_PRIV struct sr_dev_driver radioshackdmm_driver_info;
  50 static struct sr_dev_driver *di = &radioshackdmm_driver_info;
  51
  52 static const struct radioshackdmm_profile supported_radioshackdmm[] = {
  53         { RADIOSHACK_22_812, "22-812", 100 },
  54 };
  55
  56
  57 /* Properly close and free all devices. */
  58 static int clear_instances(void)
  59 {
  60         struct sr_dev_inst *sdi;
  61         struct drv_context *drvc;
  62         struct dev_context *devc;
  63         GSList *l;
  64
  65         if (!(drvc = di->priv))
  66                 return SR_OK;
  67
  68         drvc = di->priv;
  69         for (l = drvc->instances; l; l = l->next) {
  70                 if (!(sdi = l->data))
  71                         continue;
  72                 if (!(devc = sdi->priv))
  73                         continue;
  74                 sr_serial_dev_inst_free(devc->serial);
  75                 sr_dev_inst_free(sdi);
  76         }
  77         g_slist_free(drvc->instances);
  78         drvc->instances = NULL;
  79
  80         return SR_OK;
  81 }
  82
  83 static int hw_init(void)
  84 {
  85         struct drv_context *drvc;
  86
  87         if (!(drvc = g_try_malloc0(sizeof(struct drv_context)))) {
  88                 sr_err("radioshack-dmm: driver context malloc failed.");
  89                 return SR_ERR;
  90         }
  91
  92         di->priv = drvc;
  93
  94         return SR_OK;
  95 }
  96
  97 static int serial_readline(int fd, char **buf, size_t *buflen,
  98                            uint64_t timeout_ms)
  99 {
 100         uint64_t start;
 101         int maxlen, len;
 102
 103         timeout_ms *= 1000;
 104         start = g_get_monotonic_time();
 105
 106         maxlen = *buflen;
 107         *buflen = len = 0;
 108         while(1) {
 109                 len = maxlen - *buflen - 1;
 110                 if (len < 1)
 111                         break;
 112                 len = serial_read(fd, *buf + *buflen, 1);
 113                 if (len > 0) {
 114                         *buflen += len;
 115                         *(*buf + *buflen) = '\0';
 116                         if (*buflen > 0 && *(*buf + *buflen - 1) == '\r') {
 117                                 /* Strip LF and terminate. */
 118                                 *(*buf + --*buflen) = '\0';
 119                                 break;
 120                         }
 121                 }
 122                 if (g_get_monotonic_time() - start > timeout_ms)
 123                         /* Timeout */
 124                         break;
 125                 g_usleep(2000);
 126         }
 127
 128         return SR_OK;
 129 }
 130
 131 static GSList *rs_22_812_scan(const char *conn, const char *serialcomm)
 132 {
 133         struct sr_dev_inst *sdi;
 134         struct drv_context *drvc;
 135         struct dev_context *devc;
 136         struct sr_probe *probe;
 137         GSList *devices;
 138         int fd, retry;
 139         size_t len;
 140         char buf[128], *b;
 141
 142         if ((fd = serial_open(conn, O_RDONLY|O_NONBLOCK)) == -1) {
 143                 sr_err("radioshack-dmm: unable to open %s: %s",
 144                        conn, strerror(errno));
 145                 return NULL;
 146         }
 147         if (serial_set_paramstr(fd, serialcomm) != SR_OK) {
 148                 sr_err("radioshack-dmm: unable to set serial parameters");
 149                 return NULL;
 150         }
 151
 152         sr_info("radioshack-dmm: probing port %s readonly", conn);
 153
 154         drvc = di->priv;
 155         b = buf;
 156         retry = 0;
 157         devices = NULL;
 158         /* There's no way to get an ID from the multimeter. It just sends data
 159          * periodically, so the best we can do is check if the packets match the
 160          * expected format. */
 161         while (!devices && retry < 3)
 162         {
 163                 size_t i;
 164                 size_t good_packets = 0;
 165                 retry++;
 166                 serial_flush(fd);
 167
 168                 /* Let's get a bit of data and see if we can find a packet */
 169                 len = sizeof(buf);
 170                 serial_readline(fd, &b, &len, 250);
 171                 if( (len == 0) || (len < RS_22_812_PACKET_SIZE) ) {
 172                         /* Not enough data received, is the DMM connected ? */
 173                         continue;
 174                 }
 175
 176                 /* Let's treat our buffer like a stream, and find any
 177                  * valid packets */
 178                 for( i = 0; i < len - RS_22_812_PACKET_SIZE + 1;
 179                     /* don't increment i here */ )
 180                 {
 181                         const rs_22_812_packet *packet = (void *)(&buf[i]);
 182                         if( !rs_22_812_is_packet_valid(packet) ){
 183                                 i++;
 184                                 continue;
 185                         }
 186                         good_packets++;
 187                         i += RS_22_812_PACKET_SIZE;
 188                 }
 189
 190                 /* If we dropped more than two packets worth of data, something
 191                  * is wrong */
 192                 size_t dropped = len - (good_packets * RS_22_812_PACKET_SIZE);
 193                 if(dropped > 2 * RS_22_812_PACKET_SIZE)
 194                         continue;
 195
 196                 /* Let's see if we have anything good */
 197                 if (good_packets == 0)
 198                         continue;
 199
 200                 sr_info("radioshack-dmm: found RS 22-812 on port %s", conn);
 201
 202                 if (!(sdi = sr_dev_inst_new(0, SR_ST_INACTIVE, "Radioshack",
 203                                             "22-812", "")))
 204                         return NULL;
 205                 if (!(devc = g_try_malloc0(sizeof(struct dev_context)))) {
 206                         sr_dbg("radioshack-dmm: failed to malloc devc");
 207                         return NULL;
 208                 }
 209
 210                 /* devc->profile = RADIOSHACK_22_812; */
 211                 devc->serial = sr_serial_dev_inst_new(conn, -1);
 212                 devc->serialcomm = g_strdup(serialcomm);
 213
 214                 sdi->priv = devc;
 215                 sdi->driver = di;
 216                 if (!(probe = sr_probe_new(0, SR_PROBE_ANALOG, TRUE, "P1")))
 217                         return NULL;
 218                 sdi->probes = g_slist_append(sdi->probes, probe);
 219                 drvc->instances = g_slist_append(drvc->instances, sdi);
 220                 devices = g_slist_append(devices, sdi);
 221                 break;
 222
 223         }
 224         serial_close(fd);
 225
 226         return devices;
 227 }
 228
 229 static GSList *hw_scan(GSList *options)
 230 {
 231         struct sr_hwopt *opt;
 232         GSList *l, *devices;
 233         const char *conn, *serialcomm;
 234
 235         conn = serialcomm = NULL;
 236         for (l = options; l; l = l->next) {
 237                 opt = l->data;
 238                 switch (opt->hwopt) {
 239                 case SR_HWOPT_CONN:
 240                         conn = opt->value;
 241                         break;
 242                 case SR_HWOPT_SERIALCOMM:
 243                         serialcomm = opt->value;
 244                         break;
 245                 }
 246         }
 247         if (!conn)
 248                 return NULL;
 249
 250         if (serialcomm) {
 251                 /* Use the provided comm specs. */
 252                 devices = rs_22_812_scan(conn, serialcomm);
 253         } else {
 254                 /* Then try the default 4800 8n1 */
 255                 devices = rs_22_812_scan(conn, "4800/8n1");
 256         }
 257
 258         return devices;
 259 }
 260
 261 static GSList *hw_dev_list(void)
 262 {
 263         struct drv_context *drvc;
 264
 265         drvc = di->priv;
 266
 267         return drvc->instances;
 268 }
 269
 270 static int hw_dev_open(struct sr_dev_inst *sdi)
 271 {
 272         struct dev_context *devc;
 273
 274         if (!(devc = sdi->priv)) {
 275                 sr_err("radioshack-dmm: sdi->priv was NULL.");
 276                 return SR_ERR_BUG;
 277         }
 278
 279         devc->serial->fd = serial_open(devc->serial->port, O_RDONLY);
 280         if (devc->serial->fd == -1) {
 281                 sr_err("radioshack-dmm: Couldn't open serial port '%s'.",
 282                        devc->serial->port);
 283                 return SR_ERR;
 284         }
 285         if (serial_set_paramstr(devc->serial->fd, devc->serialcomm) != SR_OK) {
 286                 sr_err("radioshack-dmm: unable to set serial parameters");
 287                 return SR_ERR;
 288         }
 289         sdi->status = SR_ST_ACTIVE;
 290
 291         return SR_OK;
 292 }
 293
 294 static int hw_dev_close(struct sr_dev_inst *sdi)
 295 {
 296         struct dev_context *devc;
 297
 298         if (!(devc = sdi->priv)) {
 299                 sr_err("radioshack-dmm: sdi->priv was NULL.");
 300                 return SR_ERR_BUG;
 301         }
 302
 303         if (devc->serial && devc->serial->fd != -1) {
 304                 serial_close(devc->serial->fd);
 305                 devc->serial->fd = -1;
 306                 sdi->status = SR_ST_INACTIVE;
 307         }
 308
 309         return SR_OK;
 310 }
 311
 312 static int hw_cleanup(void)
 313 {
 314         clear_instances();
 315
 316         return SR_OK;
 317 }
 318
 319 static int hw_info_get(int info_id, const void **data,
 320        const struct sr_dev_inst *sdi)
 321 {
 322         (void)sdi; /* Does nothing. prevents "unused parameter" warning */
 323
 324         switch (info_id) {
 325         case SR_DI_HWOPTS:
 326                 *data = hwopts;
 327                 break;
 328         case SR_DI_HWCAPS:
 329                 *data = hwcaps;
 330                 break;
 331         case SR_DI_NUM_PROBES:
 332                 *data = GINT_TO_POINTER(1);
 333                 break;
 334         case SR_DI_PROBE_NAMES:
 335                 *data = probe_names;
 336                 break;
 337         default:
 338                 return SR_ERR_ARG;
 339         }
 340
 341         return SR_OK;
 342 }
 343
 344 static int hw_dev_config_set(const struct sr_dev_inst *sdi, int hwcap,
 345                 const void *value)
 346 {
 347         struct dev_context *devc;
 348
 349         if (sdi->status != SR_ST_ACTIVE)
 350                 return SR_ERR;
 351
 352         if (!(devc = sdi->priv)) {
 353                 sr_err("radioshack-dmm: sdi->priv was NULL.");
 354                 return SR_ERR_BUG;
 355         }
 356
 357         switch (hwcap) {
 358         case SR_HWCAP_LIMIT_SAMPLES:
 359                 devc->limit_samples = *(const uint64_t *)value;
 360                 sr_dbg("radioshack-dmm: Setting sample limit to %" PRIu64 ".",
 361                        devc->limit_samples);
 362                 break;
 363         default:
 364                 sr_err("radioshack-dmm: Unknown capability: %d.", hwcap);
 365                 return SR_ERR;
 366                 break;
 367         }
 368
 369         return SR_OK;
 370 }
 371
 372 static int hw_dev_acquisition_start(const struct sr_dev_inst *sdi,
 373                 void *cb_data)
 374 {
 375         struct sr_datafeed_packet packet;
 376         struct sr_datafeed_header header;
 377         struct sr_datafeed_meta_analog meta;
 378         struct dev_context *devc;
 379
 380         if (!(devc = sdi->priv)) {
 381                 sr_err("radioshack-dmm: sdi->priv was NULL.");
 382                 return SR_ERR_BUG;
 383         }
 384
 385         sr_dbg("radioshack-dmm: Starting acquisition.");
 386
 387         devc->cb_data = cb_data;
 388
 389         /* Reset the number of samples to take. If we've already collected our
 390          * quota, but we start a new session, and don't reset this, we'll just
 391          * quit without aquiring any new samples */
 392         devc->num_samples = 0;
 393
 394         /* Send header packet to the session bus. */
 395         sr_dbg("radioshack-dmm: Sending SR_DF_HEADER.");
 396         packet.type = SR_DF_HEADER;
 397         packet.payload = (uint8_t *)&header;
 398         header.feed_version = 1;
 399         gettimeofday(&header.starttime, NULL);
 400         sr_session_send(devc->cb_data, &packet);
 401
 402         /* Send metadata about the SR_DF_ANALOG packets to come. */
 403         sr_dbg("radioshack-dmm: Sending SR_DF_META_ANALOG.");
 404         packet.type = SR_DF_META_ANALOG;
 405         packet.payload = &meta;
 406         meta.num_probes = 1;
 407         sr_session_send(devc->cb_data, &packet);
 408
 409         /* Poll every 100ms, or whenever some data comes in. */
 410         sr_source_add(devc->serial->fd, G_IO_IN, 50,
 411                       radioshack_receive_data, (void *)sdi );
 412
 413         return SR_OK;
 414 }
 415
 416 static int hw_dev_acquisition_stop(const struct sr_dev_inst *sdi,
 417                 void *cb_data)
 418 {
 419         struct sr_datafeed_packet packet;
 420         struct dev_context *devc;
 421
 422         if (sdi->status != SR_ST_ACTIVE)
 423                 return SR_ERR;
 424
 425         if (!(devc = sdi->priv)) {
 426                 sr_err("radioshack-dmm: sdi->priv was NULL.");
 427                 return SR_ERR_BUG;
 428         }
 429
 430         sr_dbg("radioshack-dmm: Stopping acquisition.");
 431
 432         sr_source_remove(devc->serial->fd);
 433         hw_dev_close((struct sr_dev_inst *)sdi);
 434
 435         /* Send end packet to the session bus. */
 436         sr_dbg("radioshack-dmm: Sending SR_DF_END.");
 437         packet.type = SR_DF_END;
 438         sr_session_send(cb_data, &packet);
 439
 440         return SR_OK;
 441 }
 442
 443 SR_PRIV struct sr_dev_driver radioshackdmm_driver_info = {
 444         .name = "radioshack-dmm",
 445         .longname = "Radioshack 22-812/22-039 DMMs",
 446         .api_version = 1,
 447         .init = hw_init,
 448         .cleanup = hw_cleanup,
 449         .scan = hw_scan,
 450         .dev_list = hw_dev_list,
 451         .dev_clear = clear_instances,
 452         .dev_open = hw_dev_open,
 453         .dev_close = hw_dev_close,
 454         .info_get = hw_info_get,
 455         .dev_config_set = hw_dev_config_set,
 456         .dev_acquisition_start = hw_dev_acquisition_start,
 457         .dev_acquisition_stop = hw_dev_acquisition_stop,
 458         .priv = NULL,
 459 };