hwdriver.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2013 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 <stdlib.h>
  21 #include <stdio.h>
  22 #include <sys/types.h>
  23 #include <dirent.h>
  24 #include <string.h>
  25 #include <glib.h>
  26 #include "config.h" /* Needed for HAVE_LIBUSB_1_0 and others. */
  27 #include "libsigrok.h"
  28 #include "libsigrok-internal.h"
  29
  30 /* Message logging helpers with subsystem-specific prefix string. */
  31 #define LOG_PREFIX "hwdriver: "
  32 #define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
  33 #define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
  34 #define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
  35 #define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
  36 #define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
  37 #define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)
  38
  39 /**
  40  * @file
  41  *
  42  * Hardware driver handling in libsigrok.
  43  */
  44
  45 /**
  46  * @defgroup grp_driver Hardware drivers
  47  *
  48  * Hardware driver handling in libsigrok.
  49  *
  50  * @{
  51  */
  52
  53 static struct sr_config_info sr_config_info_data[] = {
  54         {SR_CONF_CONN, SR_T_CHAR, "conn",
  55                 "Connection", NULL},
  56         {SR_CONF_SERIALCOMM, SR_T_CHAR, "serialcomm",
  57                 "Serial communication", NULL},
  58         {SR_CONF_SAMPLERATE, SR_T_UINT64, "samplerate",
  59                 "Sample rate", NULL},
  60         {SR_CONF_CAPTURE_RATIO, SR_T_UINT64, "captureratio",
  61                 "Pre-trigger capture ratio", NULL},
  62         {SR_CONF_PATTERN_MODE, SR_T_CHAR, "pattern",
  63                 "Pattern generator mode", NULL},
  64         {SR_CONF_TRIGGER_TYPE, SR_T_CHAR, "triggertype",
  65                 "Trigger types", NULL},
  66         {SR_CONF_RLE, SR_T_BOOL, "rle",
  67                 "Run Length Encoding", NULL},
  68         {SR_CONF_TRIGGER_SLOPE, SR_T_UINT64, "triggerslope",
  69                 "Trigger slope", NULL},
  70         {SR_CONF_TRIGGER_SOURCE, SR_T_CHAR, "triggersource",
  71                 "Trigger source", NULL},
  72         {SR_CONF_HORIZ_TRIGGERPOS, SR_T_FLOAT, "horiz_triggerpos",
  73                 "Horizontal trigger position", NULL},
  74         {SR_CONF_BUFFERSIZE, SR_T_UINT64, "buffersize",
  75                 "Buffer size", NULL},
  76         {SR_CONF_TIMEBASE, SR_T_RATIONAL_PERIOD, "timebase",
  77                 "Time base", NULL},
  78         {SR_CONF_FILTER, SR_T_CHAR, "filter",
  79                 "Filter targets", NULL},
  80         {SR_CONF_VDIV, SR_T_RATIONAL_VOLT, "vdiv",
  81                 "Volts/div", NULL},
  82         {SR_CONF_COUPLING, SR_T_CHAR, "coupling",
  83                 "Coupling", NULL},
  84         {SR_CONF_DATALOG, SR_T_BOOL, "datalog",
  85                 "Datalog", NULL},
  86         {SR_CONF_SPL_WEIGHT_FREQ, SR_T_CHAR, "spl_weight_freq",
  87                 "Sound pressure level frequency weighting", NULL},
  88         {SR_CONF_SPL_WEIGHT_TIME, SR_T_CHAR, "spl_weight_time",
  89                 "Sound pressure level time weighting", NULL},
  90         {SR_CONF_HOLD_MAX, SR_T_BOOL, "hold_max",
  91                 "Hold max", NULL},
  92         {SR_CONF_HOLD_MIN, SR_T_BOOL, "hold_min",
  93                 "Hold min", NULL},
  94         {SR_CONF_SPL_MEASUREMENT_RANGE, SR_T_UINT64_RANGE, "spl_meas_range",
  95                 "Sound pressure level measurement range", NULL},
  96         {SR_CONF_POWER_OFF, SR_T_BOOL, "power_off",
  97                 "Power off", NULL},
  98         {SR_CONF_DATA_SOURCE, SR_T_CHAR, "data_source",
  99                 "Data source", NULL},
 100         {0, 0, NULL, NULL, NULL},
 101 };
 102
 103 /** @cond PRIVATE */
 104 #ifdef HAVE_HW_BRYMEN_DMM
 105 extern SR_PRIV struct sr_dev_driver brymen_bm857_driver_info;
 106 #endif
 107 #ifdef HAVE_HW_CEM_DT_885X
 108 extern SR_PRIV struct sr_dev_driver cem_dt_885x_driver_info;
 109 #endif
 110 #ifdef HAVE_HW_COLEAD_SLM
 111 extern SR_PRIV struct sr_dev_driver colead_slm_driver_info;
 112 #endif
 113 #ifdef HAVE_HW_DEMO
 114 extern SR_PRIV struct sr_dev_driver demo_driver_info;
 115 #endif
 116 #ifdef HAVE_HW_IKALOGIC_SCANALOGIC2
 117 extern SR_PRIV struct sr_dev_driver ikalogic_scanalogic2_driver_info;
 118 #endif
 119 #ifdef HAVE_HW_IKALOGIC_SCANAPLUS
 120 extern SR_PRIV struct sr_dev_driver ikalogic_scanaplus_driver_info;
 121 #ifdef HAVE_HW_KECHENG_KC_330B
 122 extern SR_PRIV struct sr_dev_driver kecheng_kc_330b_driver_info;
 123 #endif
 124 #ifdef HAVE_HW_LASCAR_EL_USB
 125 extern SR_PRIV struct sr_dev_driver lascar_el_usb_driver_info;
 126 #endif
 127 #ifdef HAVE_HW_MIC_985XX
 128 extern SR_PRIV struct sr_dev_driver mic_98581_driver_info;
 129 extern SR_PRIV struct sr_dev_driver mic_98583_driver_info;
 130 #endif
 131 #ifdef HAVE_HW_NEXUS_OSCIPRIME
 132 extern SR_PRIV struct sr_dev_driver nexus_osciprime_driver_info;
 133 #endif
 134 #ifdef HAVE_HW_OLS
 135 extern SR_PRIV struct sr_dev_driver ols_driver_info;
 136 #endif
 137 #ifdef HAVE_HW_RIGOL_DS1XX2
 138 extern SR_PRIV struct sr_dev_driver rigol_ds1xx2_driver_info;
 139 #endif
 140 #ifdef HAVE_HW_TONDAJ_SL_814
 141 extern SR_PRIV struct sr_dev_driver tondaj_sl_814_driver_info;
 142 #endif
 143 #ifdef HAVE_HW_VICTOR_DMM
 144 extern SR_PRIV struct sr_dev_driver victor_dmm_driver_info;
 145 #endif
 146 #ifdef HAVE_HW_ZEROPLUS_LOGIC_CUBE
 147 extern SR_PRIV struct sr_dev_driver zeroplus_logic_cube_driver_info;
 148 #endif
 149 #ifdef HAVE_HW_ASIX_SIGMA
 150 extern SR_PRIV struct sr_dev_driver asix_sigma_driver_info;
 151 #endif
 152 #ifdef HAVE_HW_CHRONOVU_LA8
 153 extern SR_PRIV struct sr_dev_driver chronovu_la8_driver_info;
 154 #endif
 155 #ifdef HAVE_HW_LINK_MSO19
 156 extern SR_PRIV struct sr_dev_driver link_mso19_driver_info;
 157 #endif
 158 #ifdef HAVE_HW_ALSA
 159 extern SR_PRIV struct sr_dev_driver alsa_driver_info;
 160 #endif
 161 #ifdef HAVE_HW_FX2LAFW
 162 extern SR_PRIV struct sr_dev_driver fx2lafw_driver_info;
 163 #endif
 164 #ifdef HAVE_HW_HANTEK_DSO
 165 extern SR_PRIV struct sr_dev_driver hantek_dso_driver_info;
 166 #endif
 167 #ifdef HAVE_HW_AGILENT_DMM
 168 extern SR_PRIV struct sr_dev_driver agdmm_driver_info;
 169 #endif
 170 #ifdef HAVE_HW_FLUKE_DMM
 171 extern SR_PRIV struct sr_dev_driver flukedmm_driver_info;
 172 #endif
 173 #ifdef HAVE_HW_SERIAL_DMM
 174 extern SR_PRIV struct sr_dev_driver digitek_dt4000zc_driver_info;
 175 extern SR_PRIV struct sr_dev_driver tekpower_tp4000zc_driver_info;
 176 extern SR_PRIV struct sr_dev_driver metex_me31_driver_info;
 177 extern SR_PRIV struct sr_dev_driver peaktech_3410_driver_info;
 178 extern SR_PRIV struct sr_dev_driver mastech_mas345_driver_info;
 179 extern SR_PRIV struct sr_dev_driver va_va18b_driver_info;
 180 extern SR_PRIV struct sr_dev_driver metex_m3640d_driver_info;
 181 extern SR_PRIV struct sr_dev_driver peaktech_4370_driver_info;
 182 extern SR_PRIV struct sr_dev_driver pce_pce_dm32_driver_info;
 183 extern SR_PRIV struct sr_dev_driver radioshack_22_168_driver_info;
 184 extern SR_PRIV struct sr_dev_driver radioshack_22_805_driver_info;
 185 extern SR_PRIV struct sr_dev_driver radioshack_22_812_driver_info;
 186 extern SR_PRIV struct sr_dev_driver tecpel_dmm_8060_ser_driver_info;
 187 extern SR_PRIV struct sr_dev_driver tecpel_dmm_8061_ser_driver_info;
 188 extern SR_PRIV struct sr_dev_driver voltcraft_m3650d_driver_info;
 189 extern SR_PRIV struct sr_dev_driver voltcraft_vc820_ser_driver_info;
 190 extern SR_PRIV struct sr_dev_driver voltcraft_vc830_ser_driver_info;
 191 extern SR_PRIV struct sr_dev_driver voltcraft_vc840_ser_driver_info;
 192 extern SR_PRIV struct sr_dev_driver uni_t_ut60a_ser_driver_info;
 193 extern SR_PRIV struct sr_dev_driver uni_t_ut60e_ser_driver_info;
 194 extern SR_PRIV struct sr_dev_driver uni_t_ut61d_ser_driver_info;
 195 extern SR_PRIV struct sr_dev_driver uni_t_ut61e_ser_driver_info;
 196 #endif
 197 #ifdef HAVE_HW_UNI_T_DMM
 198 extern SR_PRIV struct sr_dev_driver tecpel_dmm_8060_driver_info;
 199 extern SR_PRIV struct sr_dev_driver tecpel_dmm_8061_driver_info;
 200 extern SR_PRIV struct sr_dev_driver uni_t_ut60a_driver_info;
 201 extern SR_PRIV struct sr_dev_driver uni_t_ut60e_driver_info;
 202 extern SR_PRIV struct sr_dev_driver uni_t_ut61d_driver_info;
 203 extern SR_PRIV struct sr_dev_driver uni_t_ut61e_driver_info;
 204 extern SR_PRIV struct sr_dev_driver voltcraft_vc820_driver_info;
 205 extern SR_PRIV struct sr_dev_driver voltcraft_vc830_driver_info;
 206 extern SR_PRIV struct sr_dev_driver voltcraft_vc840_driver_info;
 207 #endif
 208 /** @endcond */
 209
 210 static struct sr_dev_driver *drivers_list[] = {
 211 #ifdef HAVE_HW_BRYMEN_DMM
 212         &brymen_bm857_driver_info,
 213 #endif
 214 #ifdef HAVE_HW_CEM_DT_885X
 215         &cem_dt_885x_driver_info,
 216 #endif
 217 #ifdef HAVE_HW_COLEAD_SLM
 218         &colead_slm_driver_info,
 219 #endif
 220 #ifdef HAVE_HW_DEMO
 221         &demo_driver_info,
 222 #endif
 223 #ifdef HAVE_HW_IKALOGIC_SCANALOGIC2
 224         &ikalogic_scanalogic2_driver_info,
 225 #endif
 226 #ifdef HAVE_HW_IKALOGIC_SCANAPLUS
 227         &ikalogic_scanaplus_driver_info,
 228 #ifdef HAVE_HW_KECHENG_KC_330B
 229         &kecheng_kc_330b_driver_info,
 230 #endif
 231 #ifdef HAVE_HW_LASCAR_EL_USB
 232         &lascar_el_usb_driver_info,
 233 #endif
 234 #ifdef HAVE_HW_MIC_985XX
 235         &mic_98581_driver_info,
 236         &mic_98583_driver_info,
 237 #endif
 238 #ifdef HAVE_HW_NEXUS_OSCIPRIME
 239         &nexus_osciprime_driver_info,
 240 #endif
 241 #ifdef HAVE_HW_OLS
 242         &ols_driver_info,
 243 #endif
 244 #ifdef HAVE_HW_RIGOL_DS1XX2
 245         &rigol_ds1xx2_driver_info,
 246 #endif
 247 #ifdef HAVE_HW_TONDAJ_SL_814
 248         &tondaj_sl_814_driver_info,
 249 #endif
 250 #ifdef HAVE_HW_VICTOR_DMM
 251         &victor_dmm_driver_info,
 252 #endif
 253 #ifdef HAVE_HW_ZEROPLUS_LOGIC_CUBE
 254         &zeroplus_logic_cube_driver_info,
 255 #endif
 256 #ifdef HAVE_HW_ASIX_SIGMA
 257         &asix_sigma_driver_info,
 258 #endif
 259 #ifdef HAVE_HW_CHRONOVU_LA8
 260         &chronovu_la8_driver_info,
 261 #endif
 262 #ifdef HAVE_HW_LINK_MSO19
 263         &link_mso19_driver_info,
 264 #endif
 265 #ifdef HAVE_HW_ALSA
 266         &alsa_driver_info,
 267 #endif
 268 #ifdef HAVE_HW_FX2LAFW
 269         &fx2lafw_driver_info,
 270 #endif
 271 #ifdef HAVE_HW_HANTEK_DSO
 272         &hantek_dso_driver_info,
 273 #endif
 274 #ifdef HAVE_HW_AGILENT_DMM
 275         &agdmm_driver_info,
 276 #endif
 277 #ifdef HAVE_HW_FLUKE_DMM
 278         &flukedmm_driver_info,
 279 #endif
 280 #ifdef HAVE_HW_SERIAL_DMM
 281         &digitek_dt4000zc_driver_info,
 282         &tekpower_tp4000zc_driver_info,
 283         &metex_me31_driver_info,
 284         &peaktech_3410_driver_info,
 285         &mastech_mas345_driver_info,
 286         &va_va18b_driver_info,
 287         &metex_m3640d_driver_info,
 288         &peaktech_4370_driver_info,
 289         &pce_pce_dm32_driver_info,
 290         &radioshack_22_168_driver_info,
 291         &radioshack_22_805_driver_info,
 292         &radioshack_22_812_driver_info,
 293         &tecpel_dmm_8060_ser_driver_info,
 294         &tecpel_dmm_8061_ser_driver_info,
 295         &voltcraft_m3650d_driver_info,
 296         &voltcraft_vc820_ser_driver_info,
 297         &voltcraft_vc830_ser_driver_info,
 298         &voltcraft_vc840_ser_driver_info,
 299         &uni_t_ut60a_ser_driver_info,
 300         &uni_t_ut60e_ser_driver_info,
 301         &uni_t_ut61d_ser_driver_info,
 302         &uni_t_ut61e_ser_driver_info,
 303 #endif
 304 #ifdef HAVE_HW_UNI_T_DMM
 305         &tecpel_dmm_8060_driver_info,
 306         &tecpel_dmm_8061_driver_info,
 307         &uni_t_ut60a_driver_info,
 308         &uni_t_ut60e_driver_info,
 309         &uni_t_ut61d_driver_info,
 310         &uni_t_ut61e_driver_info,
 311         &voltcraft_vc820_driver_info,
 312         &voltcraft_vc830_driver_info,
 313         &voltcraft_vc840_driver_info,
 314 #endif
 315         NULL,
 316 };
 317
 318 /**
 319  * Return the list of supported hardware drivers.
 320  *
 321  * @return Pointer to the NULL-terminated list of hardware driver pointers.
 322  */
 323 SR_API struct sr_dev_driver **sr_driver_list(void)
 324 {
 325
 326         return drivers_list;
 327 }
 328
 329 /**
 330  * Initialize a hardware driver.
 331  *
 332  * This usually involves memory allocations and variable initializations
 333  * within the driver, but _not_ scanning for attached devices.
 334  * The API call sr_driver_scan() is used for that.
 335  *
 336  * @param ctx A libsigrok context object allocated by a previous call to
 337  *            sr_init(). Must not be NULL.
 338  * @param driver The driver to initialize. This must be a pointer to one of
 339  *               the entries returned by sr_driver_list(). Must not be NULL.
 340  *
 341  * @return SR_OK upon success, SR_ERR_ARG upon invalid parameters,
 342  *         SR_ERR_BUG upon internal errors, or another negative error code
 343  *         upon other errors.
 344  */
 345 SR_API int sr_driver_init(struct sr_context *ctx, struct sr_dev_driver *driver)
 346 {
 347         int ret;
 348
 349         if (!ctx) {
 350                 sr_err("Invalid libsigrok context, can't initialize.");
 351                 return SR_ERR_ARG;
 352         }
 353
 354         if (!driver) {
 355                 sr_err("Invalid driver, can't initialize.");
 356                 return SR_ERR_ARG;
 357         }
 358
 359         sr_spew("Initializing driver '%s'.", driver->name);
 360         if ((ret = driver->init(ctx)) < 0)
 361                 sr_err("Failed to initialize the driver: %d.", ret);
 362
 363         return ret;
 364 }
 365
 366 /**
 367  * Tell a hardware driver to scan for devices.
 368  *
 369  * In addition to the detection, the devices that are found are also
 370  * initialized automatically. On some devices, this involves a firmware upload,
 371  * or other such measures.
 372  *
 373  * The order in which the system is scanned for devices is not specified. The
 374  * caller should not assume or rely on any specific order.
 375  *
 376  * Before calling sr_driver_scan(), the user must have previously initialized
 377  * the driver by calling sr_driver_init().
 378  *
 379  * @param driver The driver that should scan. This must be a pointer to one of
 380  *               the entries returned by sr_driver_list(). Must not be NULL.
 381  * @param options A list of 'struct sr_hwopt' options to pass to the driver's
 382  *                scanner. Can be NULL/empty.
 383  *
 384  * @return A GSList * of 'struct sr_dev_inst', or NULL if no devices were
 385  *         found (or errors were encountered). This list must be freed by the
 386  *         caller using g_slist_free(), but without freeing the data pointed
 387  *         to in the list.
 388  */
 389 SR_API GSList *sr_driver_scan(struct sr_dev_driver *driver, GSList *options)
 390 {
 391         GSList *l;
 392
 393         if (!driver) {
 394                 sr_err("Invalid driver, can't scan for devices.");
 395                 return NULL;
 396         }
 397
 398         if (!driver->priv) {
 399                 sr_err("Driver not initialized, can't scan for devices.");
 400                 return NULL;
 401         }
 402
 403         l = driver->scan(options);
 404
 405         sr_spew("Scan of '%s' found %d devices.", driver->name,
 406                 g_slist_length(l));
 407
 408         return l;
 409 }
 410
 411 /** @private */
 412 SR_PRIV void sr_hw_cleanup_all(void)
 413 {
 414         int i;
 415         struct sr_dev_driver **drivers;
 416
 417         drivers = sr_driver_list();
 418         for (i = 0; drivers[i]; i++) {
 419                 if (drivers[i]->cleanup)
 420                         drivers[i]->cleanup();
 421         }
 422 }
 423
 424 /** A floating reference can be passed in for data. */
 425 SR_PRIV struct sr_config *sr_config_new(int key, GVariant *data)
 426 {
 427         struct sr_config *src;
 428
 429         if (!(src = g_try_malloc(sizeof(struct sr_config))))
 430                 return NULL;
 431         src->key = key;
 432         src->data = g_variant_ref_sink(data);
 433
 434         return src;
 435 }
 436
 437 SR_PRIV void sr_config_free(struct sr_config *src)
 438 {
 439
 440         if (!src || !src->data) {
 441                 sr_err("%s: invalid data!", __func__);
 442                 return;
 443         }
 444
 445         g_variant_unref(src->data);
 446         g_free(src);
 447
 448 }
 449
 450 /**
 451  * Returns information about the given driver or device instance.
 452  *
 453  * @param driver The sr_dev_driver struct to query.
 454  * @param key The configuration key (SR_CONF_*).
 455  * @param data Pointer to a GVariant where the value will be stored. Must
 456  *             not be NULL. The caller is given ownership of the GVariant
 457  *             and must thus decrease the refcount after use. However if
 458  *             this function returns an error code, the field should be
 459  *             considered unused, and should not be unreferenced.
 460  * @param sdi (optional) If the key is specific to a device, this must
 461  *            contain a pointer to the struct sr_dev_inst to be checked.
 462  *            Otherwise it must be NULL.
 463  *
 464  * @return SR_OK upon success or SR_ERR in case of error. Note SR_ERR_ARG
 465  *         may be returned by the driver indicating it doesn't know that key,
 466  *         but this is not to be flagged as an error by the caller; merely
 467  *         as an indication that it's not applicable.
 468  */
 469 SR_API int sr_config_get(const struct sr_dev_driver *driver, int key,
 470                 GVariant **data, const struct sr_dev_inst *sdi)
 471 {
 472         int ret;
 473
 474         if (!driver || !data)
 475                 return SR_ERR;
 476
 477         if (!driver->config_get)
 478                 return SR_ERR_ARG;
 479
 480         if ((ret = driver->config_get(key, data, sdi)) == SR_OK) {
 481                 /* Got a floating reference from the driver. Sink it here,
 482                  * caller will need to unref when done with it. */
 483                 g_variant_ref_sink(*data);
 484         }
 485
 486         return ret;
 487 }
 488
 489 /**
 490  * Set a configuration key in a device instance.
 491  *
 492  * @param sdi The device instance.
 493  * @param key The configuration key (SR_CONF_*).
 494  * @param data The new value for the key, as a GVariant with GVariantType
 495  *        appropriate to that key. A floating reference can be passed
 496  *        in; its refcount will be sunk and unreferenced after use.
 497  *
 498  * @return SR_OK upon success or SR_ERR in case of error. Note SR_ERR_ARG
 499  *         may be returned by the driver indicating it doesn't know that key,
 500  *         but this is not to be flagged as an error by the caller; merely
 501  *         as an indication that it's not applicable.
 502  */
 503 SR_API int sr_config_set(const struct sr_dev_inst *sdi, int key, GVariant *data)
 504 {
 505         int ret;
 506
 507         g_variant_ref_sink(data);
 508
 509         if (!sdi || !sdi->driver || !data)
 510                 ret = SR_ERR;
 511         else if (!sdi->driver->config_set)
 512                 ret = SR_ERR_ARG;
 513         else
 514                 ret = sdi->driver->config_set(key, data, sdi);
 515
 516         g_variant_unref(data);
 517
 518         return ret;
 519 }
 520
 521 /**
 522  * List all possible values for a configuration key.
 523  *
 524  * @param driver The sr_dev_driver struct to query.
 525  * @param key The configuration key (SR_CONF_*).
 526  * @param data A pointer to a GVariant where the list will be stored. The
 527  *             caller is given ownership of the GVariant and must thus
 528  *             unref the GVariant after use. However if this function
 529  *             returns an error code, the field should be considered
 530  *             unused, and should not be unreferenced.
 531  * @param sdi (optional) If the key is specific to a device, this must
 532  *            contain a pointer to the struct sr_dev_inst to be checked.
 533  *
 534  * @return SR_OK upon success or SR_ERR in case of error. Note SR_ERR_ARG
 535  *         may be returned by the driver indicating it doesn't know that key,
 536  *         but this is not to be flagged as an error by the caller; merely
 537  *         as an indication that it's not applicable.
 538  */
 539 SR_API int sr_config_list(const struct sr_dev_driver *driver, int key,
 540                 GVariant **data, const struct sr_dev_inst *sdi)
 541 {
 542         int ret;
 543
 544         if (!driver || !data)
 545                 ret = SR_ERR;
 546         else if (!driver->config_list)
 547                 ret = SR_ERR_ARG;
 548         else if ((ret = driver->config_list(key, data, sdi)) == SR_OK)
 549                 g_variant_ref_sink(*data);
 550
 551         return ret;
 552 }
 553
 554 /**
 555  * Get information about a configuration key.
 556  *
 557  * @param key The configuration key.
 558  *
 559  * @return A pointer to a struct sr_config_info, or NULL if the key
 560  *         was not found.
 561  */
 562 SR_API const struct sr_config_info *sr_config_info_get(int key)
 563 {
 564         int i;
 565
 566         for (i = 0; sr_config_info_data[i].key; i++) {
 567                 if (sr_config_info_data[i].key == key)
 568                         return &sr_config_info_data[i];
 569         }
 570
 571         return NULL;
 572 }
 573
 574 /**
 575  * Get information about an configuration key, by name.
 576  *
 577  * @param optname The configuration key.
 578  *
 579  * @return A pointer to a struct sr_config_info, or NULL if the key
 580  *         was not found.
 581  */
 582 SR_API const struct sr_config_info *sr_config_info_name_get(const char *optname)
 583 {
 584         int i;
 585
 586         for (i = 0; sr_config_info_data[i].key; i++) {
 587                 if (!strcmp(sr_config_info_data[i].id, optname))
 588                         return &sr_config_info_data[i];
 589         }
 590
 591         return NULL;
 592 }
 593
 594 /* Unnecessary level of indirection follows. */
 595
 596 /** @private */
 597 SR_PRIV int sr_source_remove(int fd)
 598 {
 599         return sr_session_source_remove(fd);
 600 }
 601
 602 /** @private */
 603 SR_PRIV int sr_source_add(int fd, int events, int timeout,
 604                           sr_receive_data_callback_t cb, void *cb_data)
 605 {
 606         return sr_session_source_add(fd, events, timeout, cb, cb_data);
 607 }
 608
 609 /** @} */