usbd_cdc_interface.c

/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * Taken from ST Cube library and heavily modified.  See below for original
 * copyright header.
 */

/**
  ******************************************************************************
  * @file    USB_Device/CDC_Standalone/Src/usbd_cdc_interface.c
  * @author  MCD Application Team
  * @version V1.0.1
  * @date    26-February-2014
  * @brief   Source file for USBD CDC interface
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT(c) 2014 STMicroelectronics</center></h2>
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/

#include <stdbool.h>
#include <stdint.h>

#include "usbd_cdc_msc_hid.h"
#include "usbd_cdc_interface.h"
#include "pendsv.h"

#include "py/obj.h"
#include "lib/utils/interrupt_char.h"
#include "irq.h"

#if MICROPY_HW_ENABLE_USB

// CDC control commands
#define CDC_SEND_ENCAPSULATED_COMMAND               0x00
#define CDC_GET_ENCAPSULATED_RESPONSE               0x01
#define CDC_SET_COMM_FEATURE                        0x02
#define CDC_GET_COMM_FEATURE                        0x03
#define CDC_CLEAR_COMM_FEATURE                      0x04
#define CDC_SET_LINE_CODING                         0x20
#define CDC_GET_LINE_CODING                         0x21
#define CDC_SET_CONTROL_LINE_STATE                  0x22
#define CDC_SEND_BREAK                              0x23

// Used to control the connect_state variable when USB host opens the serial port
static uint8_t usbd_cdc_connect_tx_timer;

uint8_t *usbd_cdc_init(usbd_cdc_state_t *cdc_in) {
    usbd_cdc_itf_t *cdc = (usbd_cdc_itf_t*)cdc_in;

    // Reset the CDC state due to a new USB host connection
    // Note: we don't reset tx_buf_ptr_* in order to allow the output buffer to
    // be filled (by usbd_cdc_tx_always) before the USB device is connected, and
    // to retain transmit buffer state across multiple USB connections (they will