+ GSList *resources = NULL;
+ GDir *dir;
+ const char *dev_name;
+ char *resource;
+
+ (void)drvc;
+
+ if (!(dir = g_dir_open("/sys/class/usbmisc/", 0, NULL)))
+ if (!(dir = g_dir_open("/sys/class/usb/", 0, NULL)))
+ return NULL;
+ while ((dev_name = g_dir_read_name(dir))) {
+ if (strncmp(dev_name, "usbtmc", 6))
+ continue;
+ resource = g_strconcat("/dev/", dev_name, NULL);
+ resources = g_slist_append(resources, resource);
+ }
+ g_dir_close(dir);
+
+ return resources;
+}
+
+static int scpi_usbtmc_dev_inst_new(void *priv, struct drv_context *drvc,
+ const char *resource, char **params, const char *serialcomm)
+{
+ struct usbtmc_scpi *uscpi = priv;
+
+ (void)drvc;
+ (void)params;
+ (void)serialcomm;
+
+ if (!(uscpi->usbtmc = sr_usbtmc_dev_inst_new(resource)))
+ return SR_ERR;
+
+ return SR_OK;
+}
+
+static int scpi_usbtmc_open(void *priv)
+{
+ struct usbtmc_scpi *uscpi = priv;
+ struct sr_usbtmc_dev_inst *usbtmc = uscpi->usbtmc;