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