reworked usb serial communication (#1766)

firmware/application/usb_serial_host_to_device.hpp

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2023 Bernd Herzog
+ *
+ * This file is part of PortaPack.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#pragma once
+
+#include "ch.h"
+#include "hal.h"
+
+#define USB_BULK_BUFFER_SIZE 64
+
+void init_host_to_device();
+void serial_bulk_transfer_complete(void* user_data, unsigned int bytes_transferred);
+void schedule_host_to_device_transfer();
+void complete_host_to_device_transfer();