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_CENTER_3XX
 111 extern SR_PRIV struct sr_dev_driver center_309_driver_info;
 112 extern SR_PRIV struct sr_dev_driver voltcraft_k204_driver_info;
 113 #endif
 114 #ifdef HAVE_HW_COLEAD_SLM
 115 extern SR_PRIV struct sr_dev_driver colead_slm_driver_info;
 116 #endif
 117 #ifdef HAVE_HW_DEMO
 118 extern SR_PRIV struct sr_dev_driver demo_driver_info;
 119 #endif
 120 #ifdef HAVE_HW_IKALOGIC_SCANALOGIC2
 121 extern SR_PRIV struct sr_dev_driver ikalogic_scanalogic2_driver_info;
 122 #endif
 123 #ifdef HAVE_HW_IKALOGIC_SCANAPLUS
 124 extern SR_PRIV struct sr_dev_driver ikalogic_scanaplus_driver_info;
 125 #endif
 126 #ifdef HAVE_HW_KECHENG_KC_330B
 127 extern SR_PRIV struct sr_dev_driver kecheng_kc_330b_driver_info;
 128 #endif
 129 #ifdef HAVE_HW_LASCAR_EL_USB
 130 extern SR_PRIV struct sr_dev_driver lascar_el_usb_driver_info;
 131 #endif
 132 #ifdef HAVE_HW_MIC_985XX
 133 extern SR_PRIV struct sr_dev_driver mic_98581_driver_info;
 134 extern SR_PRIV struct sr_dev_driver mic_98583_driver_info;
 135 #endif
 136 #ifdef HAVE_HW_OLS
 137 extern SR_PRIV struct sr_dev_driver ols_driver_info;
 138 #endif
 139 #ifdef HAVE_HW_RIGOL_DS1XX2
 140 extern SR_PRIV struct sr_dev_driver rigol_ds1xx2_driver_info;
 141 #endif
 142 #ifdef HAVE_HW_TONDAJ_SL_814
 143 extern SR_PRIV struct sr_dev_driver tondaj_sl_814_driver_info;
 144 #endif
 145 #ifdef HAVE_HW_UNI_T_UT32X
 146 extern SR_PRIV struct sr_dev_driver uni_t_ut32x_driver_info;
 147 #endif
 148 #ifdef HAVE_HW_VICTOR_DMM
 149 extern SR_PRIV struct sr_dev_driver victor_dmm_driver_info;
 150 #endif
 151 #ifdef HAVE_HW_ZEROPLUS_LOGIC_CUBE
 152 extern SR_PRIV struct sr_dev_driver zeroplus_logic_cube_driver_info;
 153 #endif
 154 #ifdef HAVE_HW_ASIX_SIGMA
 155 extern SR_PRIV struct sr_dev_driver asix_sigma_driver_info;
 156 #endif
 157 #ifdef HAVE_HW_CHRONOVU_LA8
 158 extern SR_PRIV struct sr_dev_driver chronovu_la8_driver_info;
 159 #endif
 160 #ifdef HAVE_HW_LINK_MSO19
 161 extern SR_PRIV struct sr_dev_driver link_mso19_driver_info;
 162 #endif
 163 #ifdef HAVE_HW_ALSA
 164 extern SR_PRIV struct sr_dev_driver alsa_driver_info;
 165 #endif
 166 #ifdef HAVE_HW_FX2LAFW
 167 extern SR_PRIV struct sr_dev_driver fx2lafw_driver_info;
 168 #endif
 169 #ifdef HAVE_HW_HANTEK_DSO
 170 extern SR_PRIV struct sr_dev_driver hantek_dso_driver_info;
 171 #endif
 172 #ifdef HAVE_HW_AGILENT_DMM
 173 extern SR_PRIV struct sr_dev_driver agdmm_driver_info;
 174 #endif
 175 #ifdef HAVE_HW_FLUKE_DMM
 176 extern SR_PRIV struct sr_dev_driver flukedmm_driver_info;
 177 #endif
 178 #ifdef HAVE_HW_SERIAL_DMM
 179 extern SR_PRIV struct sr_dev_driver digitek_dt4000zc_driver_info;
 180 extern SR_PRIV struct sr_dev_driver tekpower_tp4000zc_driver_info;
 181 extern SR_PRIV struct sr_dev_driver metex_me31_driver_info;
 182 extern SR_PRIV struct sr_dev_driver peaktech_3410_driver_info;
 183 extern SR_PRIV struct sr_dev_driver mastech_mas345_driver_info;
 184 extern SR_PRIV struct sr_dev_driver va_va18b_driver_info;
 185 extern SR_PRIV struct sr_dev_driver metex_m3640d_driver_info;
 186 extern SR_PRIV struct sr_dev_driver peaktech_4370_driver_info;
 187 extern SR_PRIV struct sr_dev_driver pce_pce_dm32_driver_info;
 188 extern SR_PRIV struct sr_dev_driver radioshack_22_168_driver_info;
 189 extern SR_PRIV struct sr_dev_driver radioshack_22_805_driver_info;
 190 extern SR_PRIV struct sr_dev_driver radioshack_22_812_driver_info;
 191 extern SR_PRIV struct sr_dev_driver tecpel_dmm_8061_ser_driver_info;
 192 extern SR_PRIV struct sr_dev_driver voltcraft_m3650d_driver_info;
 193 extern SR_PRIV struct sr_dev_driver voltcraft_vc820_ser_driver_info;
 194 extern SR_PRIV struct sr_dev_driver voltcraft_vc830_ser_driver_info;
 195 extern SR_PRIV struct sr_dev_driver voltcraft_vc840_ser_driver_info;
 196 extern SR_PRIV struct sr_dev_driver uni_t_ut60a_ser_driver_info;
 197 extern SR_PRIV struct sr_dev_driver uni_t_ut60e_ser_driver_info;
 198 extern SR_PRIV struct sr_dev_driver uni_t_ut61d_ser_driver_info;
 199 extern SR_PRIV struct sr_dev_driver uni_t_ut61e_ser_driver_info;
 200 #endif
 201 #ifdef HAVE_HW_UNI_T_DMM
 202 extern SR_PRIV struct sr_dev_driver tecpel_dmm_8061_driver_info;
 203 extern SR_PRIV struct sr_dev_driver uni_t_ut60a_driver_info;
 204 extern SR_PRIV struct sr_dev_driver uni_t_ut60e_driver_info;
 205 extern SR_PRIV struct sr_dev_driver uni_t_ut61d_driver_info;
 206 extern SR_PRIV struct sr_dev_driver uni_t_ut61e_driver_info;
 207 extern SR_PRIV struct sr_dev_driver voltcraft_vc820_driver_info;
 208 extern SR_PRIV struct sr_dev_driver voltcraft_vc830_driver_info;
 209 extern SR_PRIV struct sr_dev_driver voltcraft_vc840_driver_info;
 210 #endif
 211 /** @endcond */
 212
 213 static struct sr_dev_driver *drivers_list[] = {
 214 #ifdef HAVE_HW_BRYMEN_DMM
 215         &brymen_bm857_driver_info,
 216 #endif
 217 #ifdef HAVE_HW_CEM_DT_885X
 218         &cem_dt_885x_driver_info,
 219 #endif
 220 #ifdef HAVE_HW_CENTER_3XX
 221         &center_309_driver_info,
 222         &voltcraft_k204_driver_info,
 223 #endif
 224 #ifdef HAVE_HW_COLEAD_SLM
 225         &colead_slm_driver_info,
 226 #endif
 227 #ifdef HAVE_HW_DEMO
 228         &demo_driver_info,
 229 #endif
 230 #ifdef HAVE_HW_IKALOGIC_SCANALOGIC2
 231         &ikalogic_scanalogic2_driver_info,
 232 #endif
 233 #ifdef HAVE_HW_IKALOGIC_SCANAPLUS
 234         &ikalogic_scanaplus_driver_info,
 235 #endif
 236 #ifdef HAVE_HW_KECHENG_KC_330B
 237         &kecheng_kc_330b_driver_info,
 238 #endif
 239 #ifdef HAVE_HW_LASCAR_EL_USB
 240         &lascar_el_usb_driver_info,
 241 #endif
 242 #ifdef HAVE_HW_MIC_985XX
 243         &mic_98581_driver_info,
 244         &mic_98583_driver_info,
 245 #endif
 246 #ifdef HAVE_HW_OLS
 247         &ols_driver_info,
 248 #endif
 249 #ifdef HAVE_HW_RIGOL_DS1XX2
 250         &rigol_ds1xx2_driver_info,
 251 #endif
 252 #ifdef HAVE_HW_TONDAJ_SL_814
 253         &tondaj_sl_814_driver_info,
 254 #endif
 255 #ifdef HAVE_HW_UNI_T_UT32X
 256         &uni_t_ut32x_driver_info,
 257 #endif
 258 #ifdef HAVE_HW_VICTOR_DMM
 259         &victor_dmm_driver_info,
 260 #endif
 261 #ifdef HAVE_HW_ZEROPLUS_LOGIC_CUBE
 262         &zeroplus_logic_cube_driver_info,
 263 #endif
 264 #ifdef HAVE_HW_ASIX_SIGMA
 265         &asix_sigma_driver_info,
 266 #endif
 267 #ifdef HAVE_HW_CHRONOVU_LA8
 268         &chronovu_la8_driver_info,
 269 #endif
 270 #ifdef HAVE_HW_LINK_MSO19
 271         &link_mso19_driver_info,
 272 #endif
 273 #ifdef HAVE_HW_ALSA
 274         &alsa_driver_info,
 275 #endif
 276 #ifdef HAVE_HW_FX2LAFW
 277         &fx2lafw_driver_info,
 278 #endif
 279 #ifdef HAVE_HW_HANTEK_DSO
 280         &hantek_dso_driver_info,
 281 #endif
 282 #ifdef HAVE_HW_AGILENT_DMM
 283         &agdmm_driver_info,
 284 #endif
 285 #ifdef HAVE_HW_FLUKE_DMM
 286         &flukedmm_driver_info,
 287 #endif
 288 #ifdef HAVE_HW_SERIAL_DMM
 289         &digitek_dt4000zc_driver_info,
 290         &tekpower_tp4000zc_driver_info,
 291         &metex_me31_driver_info,
 292         &peaktech_3410_driver_info,
 293         &mastech_mas345_driver_info,
 294         &va_va18b_driver_info,
 295         &metex_m3640d_driver_info,
 296         &peaktech_4370_driver_info,
 297         &pce_pce_dm32_driver_info,
 298         &radioshack_22_168_driver_info,
 299         &radioshack_22_805_driver_info,
 300         &radioshack_22_812_driver_info,
 301         &tecpel_dmm_8061_ser_driver_info,
 302         &voltcraft_m3650d_driver_info,
 303         &voltcraft_vc820_ser_driver_info,
 304         &voltcraft_vc830_ser_driver_info,
 305         &voltcraft_vc840_ser_driver_info,
 306         &uni_t_ut60a_ser_driver_info,
 307         &uni_t_ut60e_ser_driver_info,
 308         &uni_t_ut61d_ser_driver_info,
 309         &uni_t_ut61e_ser_driver_info,
 310 #endif
 311 #ifdef HAVE_HW_UNI_T_DMM
 312         &tecpel_dmm_8061_driver_info,
 313         &uni_t_ut60a_driver_info,
 314         &uni_t_ut60e_driver_info,
 315         &uni_t_ut61d_driver_info,
 316         &uni_t_ut61e_driver_info,
 317         &voltcraft_vc820_driver_info,
 318         &voltcraft_vc830_driver_info,
 319         &voltcraft_vc840_driver_info,
 320 #endif
 321         NULL,
 322 };
 323
 324 /**
 325  * Return the list of supported hardware drivers.
 326  *
 327  * @return Pointer to the NULL-terminated list of hardware driver pointers.
 328  */
 329 SR_API struct sr_dev_driver **sr_driver_list(void)
 330 {
 331
 332         return drivers_list;
 333 }
 334
 335 /**
 336  * Initialize a hardware driver.
 337  *
 338  * This usually involves memory allocations and variable initializations
 339  * within the driver, but _not_ scanning for attached devices.
 340  * The API call sr_driver_scan() is used for that.
 341  *
 342  * @param ctx A libsigrok context object allocated by a previous call to
 343  *            sr_init(). Must not be NULL.
 344  * @param driver The driver to initialize. This must be a pointer to one of
 345  *               the entries returned by sr_driver_list(). Must not be NULL.
 346  *
 347  * @return SR_OK upon success, SR_ERR_ARG upon invalid parameters,
 348  *         SR_ERR_BUG upon internal errors, or another negative error code
 349  *         upon other errors.
 350  */
 351 SR_API int sr_driver_init(struct sr_context *ctx, struct sr_dev_driver *driver)
 352 {
 353         int ret;
 354
 355         if (!ctx) {
 356                 sr_err("Invalid libsigrok context, can't initialize.");
 357                 return SR_ERR_ARG;
 358         }
 359
 360         if (!driver) {
 361                 sr_err("Invalid driver, can't initialize.");
 362                 return SR_ERR_ARG;
 363         }
 364
 365         sr_spew("Initializing driver '%s'.", driver->name);
 366         if ((ret = driver->init(ctx)) < 0)
 367                 sr_err("Failed to initialize the driver: %d.", ret);
 368
 369         return ret;
 370 }
 371
 372 /**
 373  * Tell a hardware driver to scan for devices.
 374  *
 375  * In addition to the detection, the devices that are found are also
 376  * initialized automatically. On some devices, this involves a firmware upload,
 377  * or other such measures.
 378  *
 379  * The order in which the system is scanned for devices is not specified. The
 380  * caller should not assume or rely on any specific order.
 381  *
 382  * Before calling sr_driver_scan(), the user must have previously initialized
 383  * the driver by calling sr_driver_init().
 384  *
 385  * @param driver The driver that should scan. This must be a pointer to one of
 386  *               the entries returned by sr_driver_list(). Must not be NULL.
 387  * @param options A list of 'struct sr_hwopt' options to pass to the driver's
 388  *                scanner. Can be NULL/empty.
 389  *
 390  * @return A GSList * of 'struct sr_dev_inst', or NULL if no devices were
 391  *         found (or errors were encountered). This list must be freed by the
 392  *         caller using g_slist_free(), but without freeing the data pointed
 393  *         to in the list.
 394  */
 395 SR_API GSList *sr_driver_scan(struct sr_dev_driver *driver, GSList *options)
 396 {
 397         GSList *l;
 398
 399         if (!driver) {
 400                 sr_err("Invalid driver, can't scan for devices.");
 401                 return NULL;
 402         }
 403
 404         if (!driver->priv) {
 405                 sr_err("Driver not initialized, can't scan for devices.");
 406                 return NULL;
 407         }
 408
 409         l = driver->scan(options);
 410
 411         sr_spew("Scan of '%s' found %d devices.", driver->name,
 412                 g_slist_length(l));
 413
 414         return l;
 415 }
 416
 417 /** @private */
 418 SR_PRIV void sr_hw_cleanup_all(void)
 419 {
 420         int i;
 421         struct sr_dev_driver **drivers;
 422
 423         drivers = sr_driver_list();
 424         for (i = 0; drivers[i]; i++) {
 425                 if (drivers[i]->cleanup)
 426                         drivers[i]->cleanup();
 427         }
 428 }
 429
 430 /** A floating reference can be passed in for data. */
 431 SR_PRIV struct sr_config *sr_config_new(int key, GVariant *data)
 432 {
 433         struct sr_config *src;
 434
 435         if (!(src = g_try_malloc(sizeof(struct sr_config))))
 436                 return NULL;
 437         src->key = key;
 438         src->data = g_variant_ref_sink(data);
 439
 440         return src;
 441 }
 442
 443 SR_PRIV void sr_config_free(struct sr_config *src)
 444 {
 445
 446         if (!src || !src->data) {
 447                 sr_err("%s: invalid data!", __func__);
 448                 return;
 449         }
 450
 451         g_variant_unref(src->data);
 452         g_free(src);
 453
 454 }
 455
 456 /**
 457  * Returns information about the given driver or device instance.
 458  *
 459  * @param driver The sr_dev_driver struct to query.
 460  * @param key The configuration key (SR_CONF_*).
 461  * @param data Pointer to a GVariant where the value will be stored. Must
 462  *             not be NULL. The caller is given ownership of the GVariant
 463  *             and must thus decrease the refcount after use. However if
 464  *             this function returns an error code, the field should be
 465  *             considered unused, and should not be unreferenced.
 466  * @param sdi (optional) If the key is specific to a device, this must
 467  *            contain a pointer to the struct sr_dev_inst to be checked.
 468  *            Otherwise it must be NULL.
 469  *
 470  * @return SR_OK upon success or SR_ERR in case of error. Note SR_ERR_ARG
 471  *         may be returned by the driver indicating it doesn't know that key,
 472  *         but this is not to be flagged as an error by the caller; merely
 473  *         as an indication that it's not applicable.
 474  */
 475 SR_API int sr_config_get(const struct sr_dev_driver *driver, int key,
 476                 GVariant **data, const struct sr_dev_inst *sdi)
 477 {
 478         int ret;
 479
 480         if (!driver || !data)
 481                 return SR_ERR;
 482
 483         if (!driver->config_get)
 484                 return SR_ERR_ARG;
 485
 486         if ((ret = driver->config_get(key, data, sdi)) == SR_OK) {
 487                 /* Got a floating reference from the driver. Sink it here,
 488                  * caller will need to unref when done with it. */
 489                 g_variant_ref_sink(*data);
 490         }
 491
 492         return ret;
 493 }
 494
 495 /**
 496  * Set a configuration key in a device instance.
 497  *
 498  * @param sdi The device instance.
 499  * @param key The configuration key (SR_CONF_*).
 500  * @param data The new value for the key, as a GVariant with GVariantType
 501  *        appropriate to that key. A floating reference can be passed
 502  *        in; its refcount will be sunk and unreferenced after use.
 503  *
 504  * @return SR_OK upon success or SR_ERR in case of error. Note SR_ERR_ARG
 505  *         may be returned by the driver indicating it doesn't know that key,
 506  *         but this is not to be flagged as an error by the caller; merely
 507  *         as an indication that it's not applicable.
 508  */
 509 SR_API int sr_config_set(const struct sr_dev_inst *sdi, int key, GVariant *data)
 510 {
 511         int ret;
 512
 513         g_variant_ref_sink(data);
 514
 515         if (!sdi || !sdi->driver || !data)
 516                 ret = SR_ERR;
 517         else if (!sdi->driver->config_set)
 518                 ret = SR_ERR_ARG;
 519         else
 520                 ret = sdi->driver->config_set(key, data, sdi);
 521
 522         g_variant_unref(data);
 523
 524         return ret;
 525 }
 526
 527 /**
 528  * List all possible values for a configuration key.
 529  *
 530  * @param driver The sr_dev_driver struct to query.
 531  * @param key The configuration key (SR_CONF_*).
 532  * @param data A pointer to a GVariant where the list will be stored. The
 533  *             caller is given ownership of the GVariant and must thus
 534  *             unref the GVariant after use. However if this function
 535  *             returns an error code, the field should be considered
 536  *             unused, and should not be unreferenced.
 537  * @param sdi (optional) If the key is specific to a device, this must
 538  *            contain a pointer to the struct sr_dev_inst to be checked.
 539  *
 540  * @return SR_OK upon success or SR_ERR in case of error. Note SR_ERR_ARG
 541  *         may be returned by the driver indicating it doesn't know that key,
 542  *         but this is not to be flagged as an error by the caller; merely
 543  *         as an indication that it's not applicable.
 544  */
 545 SR_API int sr_config_list(const struct sr_dev_driver *driver, int key,
 546                 GVariant **data, const struct sr_dev_inst *sdi)
 547 {
 548         int ret;
 549
 550         if (!driver || !data)
 551                 ret = SR_ERR;
 552         else if (!driver->config_list)
 553                 ret = SR_ERR_ARG;
 554         else if ((ret = driver->config_list(key, data, sdi)) == SR_OK)
 555                 g_variant_ref_sink(*data);
 556
 557         return ret;
 558 }
 559
 560 /**
 561  * Get information about a configuration key.
 562  *
 563  * @param key The configuration key.
 564  *
 565  * @return A pointer to a struct sr_config_info, or NULL if the key
 566  *         was not found.
 567  */
 568 SR_API const struct sr_config_info *sr_config_info_get(int key)
 569 {
 570         int i;
 571
 572         for (i = 0; sr_config_info_data[i].key; i++) {
 573                 if (sr_config_info_data[i].key == key)
 574                         return &sr_config_info_data[i];
 575         }
 576
 577         return NULL;
 578 }
 579
 580 /**
 581  * Get information about an configuration key, by name.
 582  *
 583  * @param optname The configuration key.
 584  *
 585  * @return A pointer to a struct sr_config_info, or NULL if the key
 586  *         was not found.
 587  */
 588 SR_API const struct sr_config_info *sr_config_info_name_get(const char *optname)
 589 {
 590         int i;
 591
 592         for (i = 0; sr_config_info_data[i].key; i++) {
 593                 if (!strcmp(sr_config_info_data[i].id, optname))
 594                         return &sr_config_info_data[i];
 595         }
 596
 597         return NULL;
 598 }
 599
 600 /* Unnecessary level of indirection follows. */
 601
 602 /** @private */
 603 SR_PRIV int sr_source_remove(int fd)
 604 {
 605         return sr_session_source_remove(fd);
 606 }
 607
 608 /** @private */
 609 SR_PRIV int sr_source_add(int fd, int events, int timeout,
 610                           sr_receive_data_callback_t cb, void *cb_data)
 611 {
 612         return sr_session_source_add(fd, events, timeout, cb, cb_data);
 613 }
 614
 615 /** @} */