+static void
+parse_interface_config(libusb_device *dev, struct usbdev_data *data)
+{
+ struct libusb_config_descriptor *config;
+ const struct libusb_interface *iface;
+ const struct libusb_interface_descriptor *alt;
+ int i;
+
+ data->interface = -1;
+ if (libusb_get_config_descriptor(dev, 0, &config))
+ return;
+
+ data->config = config;
+ if (!config->bNumInterfaces)
+ return;
+
+ iface = &config->interface[0];
+ if (!iface->num_altsetting)
+ return;
+
+ alt = &iface->altsetting[0];
+ data->interface = alt->bInterfaceNumber;
+ data->dev_class = alt->bInterfaceClass;
+
+ for (i = 0; i < alt->bNumEndpoints; i++) {
+ const struct libusb_endpoint_descriptor *ep = &alt->endpoint[i];
+ bool out = false;
+
+ if (data->msg_endpoint && data->response_endpoint)
+ break;
+
+ if ((ep->bmAttributes & LIBUSB_TRANSFER_TYPE_MASK) !=
+ LIBUSB_TRANSFER_TYPE_BULK)
+ continue;
+
+ out = (ep->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK) ==
+ LIBUSB_ENDPOINT_OUT;
+
+ if (!data->msg_endpoint && out)
+ data->msg_endpoint = ep->bEndpointAddress;
+ if (!data->response_endpoint && !out)
+ data->response_endpoint = ep->bEndpointAddress;
+ }
+}
+