/** @file
  Usb Debug Port library NULL instance

  Copyright (c) 2013 - 2019, Intel Corporation. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include <Base.h>

/**
  Initialize the USB3 debug port hardware.

  If no initialization is required, then return RETURN_SUCCESS.
  If the serial device was successfully initialized, then return RETURN_SUCCESS.
  If the serial device could not be initialized, then return RETURN_DEVICE_ERROR.

  @retval RETURN_SUCCESS        The serial device was initialized.
  @retval RETURN_DEVICE_ERROR   The serial device could not be initialized.

**/
RETURN_STATUS
EFIAPI
Usb3DebugPortInitialize (
  VOID
  )
{
  return RETURN_SUCCESS;
}

/**
  Write data from buffer to USB3 debug port.

  Writes NumberOfBytes data bytes from Buffer to the serial device.
  The number of bytes actually written to the serial device is returned.
  If the return value is less than NumberOfBytes, then the write operation failed.
  If Buffer is NULL, then ASSERT().
  If NumberOfBytes is zero, then return 0.

  @param  Buffer           Pointer to the data buffer to be written.
  @param  NumberOfBytes    Number of bytes to written to the serial device.

  @retval 0                NumberOfBytes is 0.
  @retval >0               The number of bytes written to the serial device.
                           If this value is less than NumberOfBytes, then the read operation failed.

**/
UINTN
EFIAPI
Usb3DebugPortWrite (
  IN UINT8     *Buffer,
  IN UINTN     NumberOfBytes
  )
{
  return 0;
}


/**
  Read data from USB3 debug port and save the datas in buffer.

  Reads NumberOfBytes data bytes from a serial device into the buffer
  specified by Buffer. The number of bytes actually read is returned.
  If the return value is less than NumberOfBytes, then the rest operation failed.
  If Buffer is NULL, then ASSERT().
  If NumberOfBytes is zero, then return 0.

  @param  Buffer           Pointer to the data buffer to store the data read from the serial device.
  @param  NumberOfBytes    Number of bytes which will be read.

  @retval 0                Read data failed, no data is to be read.
  @retval >0               Actual number of bytes read from serial device.

**/
UINTN
EFIAPI
Usb3DebugPortRead (
  OUT UINT8   *Buffer,
  IN  UINTN   NumberOfBytes
  )
{
  return 0;
}

/**
  Polls a USB3 debug port to see if there is any data waiting to be read.

  Polls a serial device to see if there is any data waiting to be read.
  If there is data waiting to be read from the serial device, then TRUE is returned.
  If there is no data waiting to be read from the serial device, then FALSE is returned.

  @retval TRUE             Data is waiting to be read from the serial device.
  @retval FALSE            There is no data waiting to be read from the serial device.

**/
BOOLEAN
EFIAPI
Usb3DebugPortPoll (
  VOID
  )
{
  return FALSE;
}