src/hardware/dcttech-usbrelay/api.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2021 Gerhard Sittig <gerhard.sittig@gmx.net>
   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 <config.h>
  21
  22 #include <hidapi.h>
  23 #include <string.h>
  24
  25 #include "protocol.h"
  26
  27 static const uint32_t scanopts[] = {
  28         SR_CONF_CONN,
  29 };
  30
  31 static const uint32_t drvopts[] = {
  32         SR_CONF_MULTIPLEXER,
  33 };
  34
  35 static const uint32_t devopts[] = {
  36         SR_CONF_CONN | SR_CONF_GET,
  37         SR_CONF_ENABLED | SR_CONF_SET, /* Enable/disable all relays at once. */
  38 };
  39
  40 static const uint32_t devopts_cg[] = {
  41         SR_CONF_ENABLED | SR_CONF_GET | SR_CONF_SET,
  42 };
  43
  44 static struct sr_dev_driver dcttech_usbrelay_driver_info;
  45
  46 static struct sr_dev_inst *probe_device(struct hid_device_info *dev,
  47         size_t relay_count)
  48 {
  49         hid_device *hid;
  50         int ret;
  51         char serno[SERNO_LENGTH + 1];
  52         uint8_t curr_state;
  53         uint8_t report[1 + REPORT_BYTECOUNT];
  54         GString *txt;
  55         size_t snr_pos;
  56         char c;
  57         struct sr_dev_inst *sdi;
  58         struct dev_context *devc;
  59         struct channel_group_context *cgc;
  60         size_t idx, nr;
  61         struct sr_channel_group *cg;
  62
  63         /* Open device, need to communicate to identify. */
  64         hid = hid_open_path(dev->path);
  65         if (!hid) {
  66                 sr_err("Cannot open %s: %ls.", dev->path, hid_error(NULL));
  67                 return NULL;
  68         }
  69
  70         /* Get an HID report. */
  71         hid_set_nonblocking(hid, 0);
  72         memset(&report, 0, sizeof(report));
  73         report[0] = REPORT_NUMBER;
  74         ret = hid_get_feature_report(hid, report, sizeof(report));
  75         hid_close(hid);
  76         if (sr_log_loglevel_get() >= SR_LOG_SPEW) {
  77                 txt = sr_hexdump_new(report, sizeof(report));
  78                 sr_spew("raw report, rc %d, bytes %s", ret, txt->str);
  79                 sr_hexdump_free(txt);
  80         }
  81         if (ret < 0) {
  82                 sr_err("Cannot read %s: %ls.", dev->path, hid_error(NULL));
  83                 return NULL;
  84         }
  85         if (ret != sizeof(report)) {
  86                 sr_err("Unexpected HID report length: %s.", dev->path);
  87                 return NULL;
  88         }
  89
  90         /*
  91          * Serial number must be all printable characters. Relay state
  92          * is for information only, gets re-retrieved before configure
  93          * API calls (get/set).
  94          */
  95         memset(serno, 0, sizeof(serno));
  96         for (snr_pos = 0; snr_pos < SERNO_LENGTH; snr_pos++) {
  97                 c = report[1 + snr_pos];
  98                 serno[snr_pos] = c;
  99                 if (c < 0x20 || c > 0x7e) {
 100                         sr_dbg("non-printable serno");
 101                         return NULL;
 102                 }
 103         }
 104         curr_state = report[1 + STATE_INDEX];
 105         sr_spew("report data, serno[%s], relays 0x%02x.", serno, curr_state);
 106
 107         /* Create a device instance. */
 108         sdi = g_malloc0(sizeof(*sdi));
 109         sdi->vendor = g_strdup_printf("%ls", dev->manufacturer_string);
 110         sdi->model = g_strdup_printf("%ls", dev->product_string);
 111         sdi->serial_num = g_strdup(serno);
 112         sdi->connection_id = g_strdup(dev->path);
 113         sdi->driver = &dcttech_usbrelay_driver_info;
 114         sdi->inst_type = SR_INST_USB;
 115
 116         /* Create channels (groups). */
 117         devc = g_malloc0(sizeof(*devc));
 118         sdi->priv = devc;
 119         devc->hid_path = g_strdup(dev->path);
 120         devc->relay_count = relay_count;
 121         devc->relay_mask = (1U << relay_count) - 1;
 122         for (idx = 0; idx < devc->relay_count; idx++) {
 123                 nr = idx + 1;
 124                 cg = g_malloc0(sizeof(*cg));
 125                 cg->name = g_strdup_printf("R%zu", nr);
 126                 cgc = g_malloc0(sizeof(*cgc));
 127                 cg->priv = cgc;
 128                 cgc->number = nr;
 129                 sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
 130         }
 131
 132         return sdi;
 133 }
 134
 135 static GSList *scan(struct sr_dev_driver *di, GSList *options)
 136 {
 137         const char *conn;
 138         GSList *devices;
 139         struct drv_context *drvc;
 140         struct hid_device_info *devs, *curdev;
 141         int ret;
 142         wchar_t *ws;
 143         char nonws[32];
 144         char *s, *endp;
 145         unsigned long relay_count;
 146         struct sr_dev_inst *sdi;
 147
 148         /* Get optional conn= spec when provided. */
 149         conn = NULL;
 150         (void)sr_serial_extract_options(options, &conn, NULL);
 151         if (conn && !*conn)
 152                 conn = NULL;
 153         /*
 154          * TODO Accept different types of conn= specs? Either paths that
 155          * hidapi(3) can open. Or bus.addr specs that we can check for
 156          * during USB enumeration. Derive want_path, want_bus, want_addr
 157          * here from the optional conn= spec.
 158          */
 159
 160         devices = NULL;
 161         drvc = di->context;
 162         drvc->instances = NULL;
 163
 164         /*
 165          * The firmware is V-USB based. The USB VID:PID identification
 166          * is shared across several projects. Need to inspect the vendor
 167          * and product _strings_ to actually identify the device.
 168          *
 169          * The USB serial number need not be present nor reliable. The
 170          * HID report contains a five character string which may serve
 171          * as an identification for boards (is said to differ between
 172          * boards). The last byte encodes the current relays state.
 173          */
 174         devs = hid_enumerate(VENDOR_ID, PRODUCT_ID);
 175         for (curdev = devs; curdev; curdev = curdev->next) {
 176                 if (!curdev->vendor_id || !curdev->product_id)
 177                         continue;
 178                 if (!curdev->manufacturer_string || !curdev->product_string)
 179                         continue;
 180                 if (!*curdev->manufacturer_string || !*curdev->product_string)
 181                         continue;
 182                 if (conn && strcmp(curdev->path, conn) != 0) {
 183                         sr_dbg("skipping %s, conn= mismatch", curdev->path);
 184                         continue;
 185                 }
 186                 sr_dbg("checking %04hx:%04hx, vendor %ls, product %ls.",
 187                         curdev->vendor_id, curdev->product_id,
 188                         curdev->manufacturer_string, curdev->product_string);
 189
 190                 /* Check USB details retrieved by enumeration. */
 191                 ws = curdev->manufacturer_string;
 192                 if (!ws || !wcslen(ws))
 193                         continue;
 194                 snprintf(nonws, sizeof(nonws), "%ls", ws);
 195                 if (strcmp(nonws, VENDOR_STRING) != 0)
 196                         continue;
 197                 ws = curdev->product_string;
 198                 if (!ws || !wcslen(ws))
 199                         continue;
 200                 snprintf(nonws, sizeof(nonws), "%ls", ws);
 201                 s = nonws;
 202                 if (!g_str_has_prefix(s, PRODUCT_STRING_PREFIX))
 203                         continue;
 204                 s += strlen(PRODUCT_STRING_PREFIX);
 205                 ret = sr_atoul_base(s, &relay_count, &endp, 10);
 206                 if (ret != SR_OK || !endp || *endp)
 207                         continue;
 208                 sr_info("Found: HID path %s, relay count %lu.",
 209                         curdev->path, relay_count);
 210
 211                 /* Identify device by communicating to it. */
 212                 sdi = probe_device(curdev, relay_count);
 213                 if (!sdi) {
 214                         sr_warn("Failed to communicate to %s.", curdev->path);
 215                         continue;
 216                 }
 217                 devices = g_slist_append(devices, sdi);
 218         }
 219         hid_free_enumeration(devs);
 220
 221         return devices;
 222 }
 223
 224 static int dev_open(struct sr_dev_inst *sdi)
 225 {
 226         struct dev_context *devc;
 227
 228         devc = sdi->priv;
 229
 230         if (devc->hid_dev) {
 231                 hid_close(devc->hid_dev);
 232                 devc->hid_dev = NULL;
 233         }
 234
 235         devc->hid_dev = hid_open_path(devc->hid_path);
 236         if (!devc->hid_dev)
 237                 return SR_ERR_IO;
 238
 239         (void)dcttech_usbrelay_update_state(sdi);
 240
 241         return SR_OK;
 242 }
 243
 244 static int dev_close(struct sr_dev_inst *sdi)
 245 {
 246         struct dev_context *devc;
 247
 248         devc = sdi->priv;
 249
 250         if (devc->hid_dev) {
 251                 hid_close(devc->hid_dev);
 252                 devc->hid_dev = NULL;
 253         }
 254
 255         return SR_OK;
 256 }
 257
 258 static int config_get(uint32_t key, GVariant **data,
 259         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 260 {
 261         gboolean on;
 262         int ret;
 263
 264         if (!cg) {
 265                 switch (key) {
 266                 case SR_CONF_CONN:
 267                         if (!sdi->connection_id)
 268                                 return SR_ERR_NA;
 269                         *data = g_variant_new_string(sdi->connection_id);
 270                         return SR_OK;
 271                 default:
 272                         return SR_ERR_NA;
 273                 }
 274         }
 275
 276         switch (key) {
 277         case SR_CONF_ENABLED:
 278                 ret = dcttech_usbrelay_query_cg(sdi, cg, &on);
 279                 if (ret != SR_OK)
 280                         return ret;
 281                 *data = g_variant_new_boolean(on);
 282                 return SR_OK;
 283         default:
 284                 return SR_ERR_NA;
 285         }
 286 }
 287
 288 static int config_set(uint32_t key, GVariant *data,
 289         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 290 {
 291         gboolean on;
 292
 293         if (!cg) {
 294                 switch (key) {
 295                 case SR_CONF_ENABLED:
 296                         /* Enable/disable all channels at the same time. */
 297                         on = g_variant_get_boolean(data);
 298                         return dcttech_usbrelay_switch_cg(sdi, cg, on);
 299                 default:
 300                         return SR_ERR_NA;
 301                 }
 302         } else {
 303                 switch (key) {
 304                 case SR_CONF_ENABLED:
 305                         on = g_variant_get_boolean(data);
 306                         return dcttech_usbrelay_switch_cg(sdi, cg, on);
 307                 default:
 308                         return SR_ERR_NA;
 309                 }
 310         }
 311
 312         return SR_OK;
 313 }
 314
 315 static int config_list(uint32_t key, GVariant **data,
 316         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 317 {
 318
 319         if (!cg) {
 320                 switch (key) {
 321                 case SR_CONF_SCAN_OPTIONS:
 322                 case SR_CONF_DEVICE_OPTIONS:
 323                         return STD_CONFIG_LIST(key, data, sdi, cg,
 324                                 scanopts, drvopts, devopts);
 325                 default:
 326                         return SR_ERR_NA;
 327                 }
 328         }
 329
 330         switch (key) {
 331         case SR_CONF_DEVICE_OPTIONS:
 332                 *data = std_gvar_array_u32(ARRAY_AND_SIZE(devopts_cg));
 333                 return SR_OK;
 334         default:
 335                 return SR_ERR_NA;
 336         }
 337 }
 338
 339 static struct sr_dev_driver dcttech_usbrelay_driver_info = {
 340         .name = "dcttech-usbrelay",
 341         .longname = "dcttech usbrelay",
 342         .api_version = 1,
 343         .init = std_init,
 344         .cleanup = std_cleanup,
 345         .scan = scan,
 346         .dev_list = std_dev_list,
 347         .dev_clear = std_dev_clear,
 348         .config_get = config_get,
 349         .config_set = config_set,
 350         .config_list = config_list,
 351         .dev_open = dev_open,
 352         .dev_close = dev_close,
 353         .dev_acquisition_start = std_dummy_dev_acquisition_start,
 354         .dev_acquisition_stop = std_dummy_dev_acquisition_stop,
 355         .context = NULL,
 356 };
 357 SR_REGISTER_DEV_DRIVER(dcttech_usbrelay_driver_info);