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 <sys/types.h>
  23 #include <sys/stat.h>
  24 #include <fcntl.h>
  25 #include <string.h>
  26 #include <errno.h>
  27 #include "libsigrok.h"
  28 #include "libsigrok-internal.h"
  29 #include "protocol.h"
  30
  31 #define SERIALCOMM "4800/8n1"
  32
  33 static const int hwopts[] = {
  34         SR_HWOPT_CONN,
  35         SR_HWOPT_SERIALCOMM,
  36         0,
  37 };
  38
  39 static const int hwcaps[] = {
  40         SR_HWCAP_MULTIMETER,
  41         SR_HWCAP_LIMIT_SAMPLES,
  42         SR_HWCAP_CONTINUOUS,
  43         0,
  44 };
  45
  46 static const char *probe_names[] = {
  47         "Probe",
  48         NULL,
  49 };
  50
  51 SR_PRIV struct sr_dev_driver radioshackdmm_driver_info;
  52 static struct sr_dev_driver *di = &radioshackdmm_driver_info;
  53
  54 /* Properly close and free all devices. */
  55 static int clear_instances(void)
  56 {
  57         struct sr_dev_inst *sdi;
  58         struct drv_context *drvc;
  59         struct dev_context *devc;
  60         GSList *l;
  61
  62         if (!(drvc = di->priv))
  63                 return SR_OK;
  64
  65         drvc = di->priv;
  66         for (l = drvc->instances; l; l = l->next) {
  67                 if (!(sdi = l->data))
  68                         continue;
  69                 if (!(devc = sdi->priv))
  70                         continue;
  71                 sr_serial_dev_inst_free(devc->serial);
  72                 sr_dev_inst_free(sdi);
  73         }
  74         g_slist_free(drvc->instances);
  75         drvc->instances = NULL;
  76
  77         return SR_OK;
  78 }
  79
  80 static int hw_init(void)
  81 {
  82         struct drv_context *drvc;
  83
  84         if (!(drvc = g_try_malloc0(sizeof(struct drv_context)))) {
  85                 sr_err("Driver context malloc failed.");
  86                 return SR_ERR_MALLOC;
  87         }
  88
  89         di->priv = drvc;
  90
  91         return SR_OK;
  92 }
  93
  94 static GSList *rs_22_812_scan(const char *conn, const char *serialcomm)
  95 {
  96         struct sr_dev_inst *sdi;
  97         struct drv_context *drvc;
  98         struct dev_context *devc;
  99         struct sr_probe *probe;
 100         struct sr_serial_dev_inst *serial;
 101         GSList *devices;
 102         int retry;
 103         size_t len, i, good_packets, dropped;
 104         char buf[128], *b;
 105         const struct rs_22_812_packet *rs_packet;
 106
 107         if (!(serial = sr_serial_dev_inst_new(conn, serialcomm)))
 108                 return NULL;
 109
 110         if (serial_open(serial, O_RDONLY|O_NONBLOCK) != SR_OK)
 111                 return NULL;
 112
 113         sr_info("Probing port '%s' readonly.", conn);
 114
 115         drvc = di->priv;
 116         b = buf;
 117         retry = 0;
 118         devices = NULL;
 119
 120         /*
 121          * There's no way to get an ID from the multimeter. It just sends data
 122          * periodically, so the best we can do is check if the packets match
 123          * the expected format.
 124          */
 125         while (!devices && retry < 3) {
 126                 good_packets = 0;
 127                 retry++;
 128                 serial_flush(serial);
 129
 130                 /* Let's get a bit of data and see if we can find a packet. */
 131                 len = sizeof(buf);
 132                 serial_readline(serial, &b, &len, 250);
 133                 if ((len == 0) || (len < RS_22_812_PACKET_SIZE)) {
 134                         /* Not enough data received, is the DMM connected? */
 135                         continue;
 136                 }
 137
 138                 /* Treat our buffer as stream, and find any valid packets. */
 139                 for (i = 0; i < len - RS_22_812_PACKET_SIZE + 1;) {
 140                         rs_packet = (void *)(&buf[i]);
 141                         if (!rs_22_812_packet_valid(rs_packet)) {
 142                                 i++;
 143                                 continue;
 144                         }
 145                         good_packets++;
 146                         i += RS_22_812_PACKET_SIZE;
 147                 }
 148
 149                 /* If we dropped more than two packets, something is wrong. */
 150                 dropped = len - (good_packets * RS_22_812_PACKET_SIZE);
 151                 if (dropped > 2 * RS_22_812_PACKET_SIZE)
 152                         continue;
 153
 154                 /* Let's see if we have anything good. */
 155                 if (good_packets == 0)
 156                         continue;
 157
 158                 sr_info("Found RadioShack 22-812 on port '%s'.", conn);
 159
 160                 if (!(sdi = sr_dev_inst_new(0, SR_ST_INACTIVE, "RadioShack",
 161                                             "22-812", "")))
 162                         return NULL;
 163
 164                 if (!(devc = g_try_malloc0(sizeof(struct dev_context)))) {
 165                         sr_err("Device context malloc failed.");
 166                         return NULL;
 167                 }
 168
 169                 devc->serial = serial;
 170
 171                 sdi->priv = devc;
 172                 sdi->driver = di;
 173                 if (!(probe = sr_probe_new(0, SR_PROBE_ANALOG, TRUE, "P1")))
 174                         return NULL;
 175                 sdi->probes = g_slist_append(sdi->probes, probe);
 176                 drvc->instances = g_slist_append(drvc->instances, sdi);
 177                 devices = g_slist_append(devices, sdi);
 178                 break;
 179         }
 180         serial_close(serial);
 181
 182         return devices;
 183 }
 184
 185 static GSList *hw_scan(GSList * options)
 186 {
 187         struct sr_hwopt *opt;
 188         GSList *l, *devices;
 189         const char *conn, *serialcomm;
 190
 191         conn = serialcomm = NULL;
 192         for (l = options; l; l = l->next) {
 193                 opt = l->data;
 194                 switch (opt->hwopt) {
 195                 case SR_HWOPT_CONN:
 196                         conn = opt->value;
 197                         break;
 198                 case SR_HWOPT_SERIALCOMM:
 199                         serialcomm = opt->value;
 200                         break;
 201                 }
 202         }
 203         if (!conn)
 204                 return NULL;
 205
 206         if (serialcomm)
 207                 /* Use the provided comm specs. */
 208                 devices = rs_22_812_scan(conn, serialcomm);
 209         else
 210                 /* Try the default. */
 211                 devices = rs_22_812_scan(conn, SERIALCOMM);
 212
 213         return devices;
 214 }
 215
 216 static GSList *hw_dev_list(void)
 217 {
 218         struct drv_context *drvc;
 219
 220         drvc = di->priv;
 221
 222         return drvc->instances;
 223 }
 224
 225 static int hw_dev_open(struct sr_dev_inst *sdi)
 226 {
 227         struct dev_context *devc;
 228
 229         if (!(devc = sdi->priv)) {
 230                 sr_err("sdi->priv was NULL.");
 231                 return SR_ERR_BUG;
 232         }
 233
 234         if (serial_open(devc->serial, O_RDONLY) != SR_OK)
 235                 return SR_ERR;
 236
 237         sdi->status = SR_ST_ACTIVE;
 238
 239         return SR_OK;
 240 }
 241
 242 static int hw_dev_close(struct sr_dev_inst *sdi)
 243 {
 244         struct dev_context *devc;
 245
 246         if (!(devc = sdi->priv)) {
 247                 sr_err("sdi->priv was NULL.");
 248                 return SR_ERR_BUG;
 249         }
 250
 251         if (devc->serial && devc->serial->fd != -1) {
 252                 serial_close(devc->serial);
 253                 sdi->status = SR_ST_INACTIVE;
 254         }
 255
 256         return SR_OK;
 257 }
 258
 259 static int hw_cleanup(void)
 260 {
 261         clear_instances();
 262
 263         return SR_OK;
 264 }
 265
 266 static int hw_info_get(int info_id, const void **data,
 267                        const struct sr_dev_inst *sdi)
 268 {
 269         (void)sdi;
 270
 271         switch (info_id) {
 272         case SR_DI_HWOPTS:
 273                 *data = hwopts;
 274                 break;
 275         case SR_DI_HWCAPS:
 276                 *data = hwcaps;
 277                 break;
 278         case SR_DI_NUM_PROBES:
 279                 *data = GINT_TO_POINTER(1);
 280                 break;
 281         case SR_DI_PROBE_NAMES:
 282                 *data = probe_names;
 283                 break;
 284         default:
 285                 sr_err("Unknown info_id: %d.", info_id);
 286                 return SR_ERR_ARG;
 287         }
 288
 289         return SR_OK;
 290 }
 291
 292 static int hw_dev_config_set(const struct sr_dev_inst *sdi, int hwcap,
 293                              const void *value)
 294 {
 295         struct dev_context *devc;
 296
 297         if (sdi->status != SR_ST_ACTIVE)
 298                 return SR_ERR;
 299
 300         if (!(devc = sdi->priv)) {
 301                 sr_err("sdi->priv was NULL.");
 302                 return SR_ERR_BUG;
 303         }
 304
 305         switch (hwcap) {
 306         case SR_HWCAP_LIMIT_SAMPLES:
 307                 devc->limit_samples = *(const uint64_t *)value;
 308                 sr_dbg("Setting sample limit to %" PRIu64 ".",
 309                        devc->limit_samples);
 310                 break;
 311         default:
 312                 sr_err("Unknown capability: %d.", hwcap);
 313                 return SR_ERR_ARG;
 314                 break;
 315         }
 316
 317         return SR_OK;
 318 }
 319
 320 static int hw_dev_acquisition_start(const struct sr_dev_inst *sdi,
 321                                     void *cb_data)
 322 {
 323         struct sr_datafeed_packet packet;
 324         struct sr_datafeed_header header;
 325         struct sr_datafeed_meta_analog meta;
 326         struct dev_context *devc;
 327
 328         if (!(devc = sdi->priv)) {
 329                 sr_err("sdi->priv was NULL.");
 330                 return SR_ERR_BUG;
 331         }
 332
 333         sr_dbg("Starting acquisition.");
 334
 335         devc->cb_data = cb_data;
 336
 337         /*
 338          * Reset the number of samples to take. If we've already collected our
 339          * quota, but we start a new session, and don't reset this, we'll just
 340          * quit without aquiring any new samples.
 341          */
 342         devc->num_samples = 0;
 343
 344         /* Send header packet to the session bus. */
 345         sr_dbg("Sending SR_DF_HEADER.");
 346         packet.type = SR_DF_HEADER;
 347         packet.payload = (uint8_t *) & header;
 348         header.feed_version = 1;
 349         gettimeofday(&header.starttime, NULL);
 350         sr_session_send(devc->cb_data, &packet);
 351
 352         /* Send metadata about the SR_DF_ANALOG packets to come. */
 353         sr_dbg("Sending SR_DF_META_ANALOG.");
 354         packet.type = SR_DF_META_ANALOG;
 355         packet.payload = &meta;
 356         meta.num_probes = 1;
 357         sr_session_send(devc->cb_data, &packet);
 358
 359         /* Poll every 50ms, or whenever some data comes in. */
 360         sr_source_add(devc->serial->fd, G_IO_IN, 50,
 361                       radioshack_dmm_receive_data, (void *)sdi);
 362
 363         return SR_OK;
 364 }
 365
 366 static int hw_dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
 367 {
 368         struct sr_datafeed_packet packet;
 369         struct dev_context *devc;
 370
 371         if (sdi->status != SR_ST_ACTIVE)
 372                 return SR_ERR;
 373
 374         if (!(devc = sdi->priv)) {
 375                 sr_err("sdi->priv was NULL.");
 376                 return SR_ERR_BUG;
 377         }
 378
 379         sr_dbg("Stopping acquisition.");
 380
 381         sr_source_remove(devc->serial->fd);
 382         hw_dev_close((struct sr_dev_inst *)sdi);
 383
 384         /* Send end packet to the session bus. */
 385         sr_dbg("Sending SR_DF_END.");
 386         packet.type = SR_DF_END;
 387         sr_session_send(cb_data, &packet);
 388
 389         return SR_OK;
 390 }
 391
 392 SR_PRIV struct sr_dev_driver radioshackdmm_driver_info = {
 393         .name = "radioshack-dmm",
 394         .longname = "RadioShack 22-812/22-039 DMMs",
 395         .api_version = 1,
 396         .init = hw_init,
 397         .cleanup = hw_cleanup,
 398         .scan = hw_scan,
 399         .dev_list = hw_dev_list,
 400         .dev_clear = clear_instances,
 401         .dev_open = hw_dev_open,
 402         .dev_close = hw_dev_close,
 403         .info_get = hw_info_get,
 404         .dev_config_set = hw_dev_config_set,
 405         .dev_acquisition_start = hw_dev_acquisition_start,
 406         .dev_acquisition_stop = hw_dev_acquisition_stop,
 407         .priv = NULL,
 408 };