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         sdi->serial_num = g_strdup(serno);
 102         sdi->connection_id = g_strdup(path);
 103         devc = g_malloc0(sizeof(*devc));
 104         sdi->priv = devc;
 105         devc->hid_path = g_strdup(path);
 106         devc->relay_count = relay_count;
 107         devc->relay_mask = (1U << relay_count) - 1;
 108         for (idx = 0; idx < devc->relay_count; idx++) {
 109                 nr = idx + 1;
 110                 cg = g_malloc0(sizeof(*cg));
 111                 cg->name = g_strdup_printf("R%zu", nr);
 112                 cgc = g_malloc0(sizeof(*cgc));
 113                 cg->priv = cgc;
 114                 cgc->number = nr;
 115                 sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
 116         }
 117
 118         return sdi;
 119 }
 120
 121 static GSList *scan(struct sr_dev_driver *di, GSList *options)
 122 {
 123         const char *conn;
 124         GSList *devices;
 125         struct drv_context *drvc;
 126         struct hid_device_info *devs, *curdev;
 127         int ret;
 128         wchar_t *ws;
 129         char nonws[32];
 130         char *s, *endp;
 131         unsigned long relay_count;
 132         struct sr_dev_inst *sdi;
 133
 134         /* Get optional conn= spec when provided. */
 135         conn = NULL;
 136         (void)sr_serial_extract_options(options, &conn, NULL);
 137         if (conn && !*conn)
 138                 conn = NULL;
 139         /*
 140          * TODO Accept different types of conn= specs? Either paths that
 141          * hidapi(3) can open. Or bus.addr specs that we can check for
 142          * during USB enumeration. Derive want_path, want_bus, want_addr
 143          * here from the optional conn= spec.
 144          */
 145
 146         devices = NULL;
 147         drvc = di->context;
 148         drvc->instances = NULL;
 149
 150         /*
 151          * The firmware is V-USB based. The USB VID:PID identification
 152          * is shared across several projects. Need to inspect the vendor
 153          * and product _strings_ to actually identify the device.
 154          *
 155          * The USB serial number need not be present nor reliable. The
 156          * HID report contains a five character string which may serve
 157          * as an identification for boards (is said to differ between
 158          * boards). The last byte encodes the current relays state.
 159          */
 160         devs = hid_enumerate(VENDOR_ID, PRODUCT_ID);
 161         for (curdev = devs; curdev; curdev = curdev->next) {
 162                 if (!curdev->vendor_id || !curdev->product_id)
 163                         continue;
 164                 if (!curdev->manufacturer_string || !curdev->product_string)
 165                         continue;
 166                 if (!*curdev->manufacturer_string || !*curdev->product_string)
 167                         continue;
 168                 if (conn && strcmp(curdev->path, conn) != 0) {
 169                         sr_dbg("skipping %s, conn= mismatch", curdev->path);
 170                         continue;
 171                 }
 172                 sr_dbg("checking %04hx:%04hx, vendor %ls, product %ls.",
 173                         curdev->vendor_id, curdev->product_id,
 174                         curdev->manufacturer_string, curdev->product_string);
 175
 176                 /* Check USB details retrieved by enumeration. */
 177                 ws = curdev->manufacturer_string;
 178                 if (!ws || !wcslen(ws))
 179                         continue;
 180                 snprintf(nonws, sizeof(nonws), "%ls", ws);
 181                 if (strcmp(nonws, VENDOR_STRING) != 0)
 182                         continue;
 183                 ws = curdev->product_string;
 184                 if (!ws || !wcslen(ws))
 185                         continue;
 186                 snprintf(nonws, sizeof(nonws), "%ls", ws);
 187                 s = nonws;
 188                 if (!g_str_has_prefix(s, PRODUCT_STRING_PREFIX))
 189                         continue;
 190                 s += strlen(PRODUCT_STRING_PREFIX);
 191                 ret = sr_atoul_base(s, &relay_count, &endp, 10);
 192                 if (ret != SR_OK || !endp || *endp)
 193                         continue;
 194                 sr_info("Found: HID path %s, relay count %lu.",
 195                         curdev->path, relay_count);
 196
 197                 /* Identify device by communicating to it. */
 198                 sdi = probe_device(curdev->path, relay_count);
 199                 if (!sdi) {
 200                         sr_warn("Failed to communicate to %s.", curdev->path);
 201                         continue;
 202                 }
 203
 204                 /* Amend driver instance from USB enumeration details. */
 205                 sdi->vendor = g_strdup_printf("%ls", curdev->manufacturer_string);
 206                 sdi->model = g_strdup_printf("%ls", curdev->product_string);
 207                 sdi->driver = &dcttech_usbrelay_driver_info;
 208                 sdi->inst_type = SR_INST_USB;
 209
 210                 devices = g_slist_append(devices, sdi);
 211         }
 212         hid_free_enumeration(devs);
 213
 214         return devices;
 215 }
 216
 217 static int dev_open(struct sr_dev_inst *sdi)
 218 {
 219         struct dev_context *devc;
 220
 221         devc = sdi->priv;
 222
 223         if (devc->hid_dev) {
 224                 hid_close(devc->hid_dev);
 225                 devc->hid_dev = NULL;
 226         }
 227
 228         devc->hid_dev = hid_open_path(devc->hid_path);
 229         if (!devc->hid_dev)
 230                 return SR_ERR_IO;
 231
 232         (void)dcttech_usbrelay_update_state(sdi);
 233
 234         return SR_OK;
 235 }
 236
 237 static int dev_close(struct sr_dev_inst *sdi)
 238 {
 239         struct dev_context *devc;
 240
 241         devc = sdi->priv;
 242
 243         if (devc->hid_dev) {
 244                 hid_close(devc->hid_dev);
 245                 devc->hid_dev = NULL;
 246         }
 247
 248         return SR_OK;
 249 }
 250
 251 static int config_get(uint32_t key, GVariant **data,
 252         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 253 {
 254         gboolean on;
 255         int ret;
 256
 257         if (!cg) {
 258                 switch (key) {
 259                 case SR_CONF_CONN:
 260                         if (!sdi->connection_id)
 261                                 return SR_ERR_NA;
 262                         *data = g_variant_new_string(sdi->connection_id);
 263                         return SR_OK;
 264                 default:
 265                         return SR_ERR_NA;
 266                 }
 267         }
 268
 269         switch (key) {
 270         case SR_CONF_ENABLED:
 271                 ret = dcttech_usbrelay_query_cg(sdi, cg, &on);
 272                 if (ret != SR_OK)
 273                         return ret;
 274                 *data = g_variant_new_boolean(on);
 275                 return SR_OK;
 276         default:
 277                 return SR_ERR_NA;
 278         }
 279 }
 280
 281 static int config_set(uint32_t key, GVariant *data,
 282         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 283 {
 284         gboolean on;
 285
 286         if (!cg) {
 287                 switch (key) {
 288                 case SR_CONF_ENABLED:
 289                         /* Enable/disable all channels at the same time. */
 290                         on = g_variant_get_boolean(data);
 291                         return dcttech_usbrelay_switch_cg(sdi, cg, on);
 292                 default:
 293                         return SR_ERR_NA;
 294                 }
 295         } else {
 296                 switch (key) {
 297                 case SR_CONF_ENABLED:
 298                         on = g_variant_get_boolean(data);
 299                         return dcttech_usbrelay_switch_cg(sdi, cg, on);
 300                 default:
 301                         return SR_ERR_NA;
 302                 }
 303         }
 304
 305         return SR_OK;
 306 }
 307
 308 static int config_list(uint32_t key, GVariant **data,
 309         const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 310 {
 311
 312         if (!cg) {
 313                 switch (key) {
 314                 case SR_CONF_SCAN_OPTIONS:
 315                 case SR_CONF_DEVICE_OPTIONS:
 316                         return STD_CONFIG_LIST(key, data, sdi, cg,
 317                                 scanopts, drvopts, devopts);
 318                 default:
 319                         return SR_ERR_NA;
 320                 }
 321         }
 322
 323         switch (key) {
 324         case SR_CONF_DEVICE_OPTIONS:
 325                 *data = std_gvar_array_u32(ARRAY_AND_SIZE(devopts_cg));
 326                 return SR_OK;
 327         default:
 328                 return SR_ERR_NA;
 329         }
 330 }
 331
 332 static struct sr_dev_driver dcttech_usbrelay_driver_info = {
 333         .name = "dcttech-usbrelay",
 334         .longname = "dcttech usbrelay",
 335         .api_version = 1,
 336         .init = std_init,
 337         .cleanup = std_cleanup,
 338         .scan = scan,
 339         .dev_list = std_dev_list,
 340         .dev_clear = std_dev_clear,
 341         .config_get = config_get,
 342         .config_set = config_set,
 343         .config_list = config_list,
 344         .dev_open = dev_open,
 345         .dev_close = dev_close,
 346         .dev_acquisition_start = std_dummy_dev_acquisition_start,
 347         .dev_acquisition_stop = std_dummy_dev_acquisition_stop,
 348         .context = NULL,
 349 };
 350 SR_REGISTER_DEV_DRIVER(dcttech_usbrelay_driver_info);