audk/MdePkg/Library/SerialPortLibNull/SerialPortLibNull.c

/** @file
  Null Serial Port library instance with empty functions.

  Copyright (c) 2006 - 2008, Intel Corporation
  All rights reserved. This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/


#include <Base.h>


#include <Library/SerialPortLib.h>

/**
  Programmed hardware of Serial port.

  @return    Always return RETURN_UNSUPPORTED.

**/
RETURN_STATUS
EFIAPI
SerialPortInitialize (
  VOID
  )
{
  return RETURN_UNSUPPORTED;
}

/**
  Write data to serial device.

  @param  Buffer           Point of data buffer which need to be writed.
  @param  NumberOfBytes    Number of output bytes which are cached in Buffer.

  @retval 0                No data is to be written.

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


/**
  Read data from serial device and save the datas in buffer.

  @param  Buffer           Point of data buffer, which contains the data
                           returned from the serial device.
  @param  NumberOfBytes    Number of bytes which will be read.

  @retval 0                No data is to be read.

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

/**
  Poll the serial device to see if there is any data waiting.

  If there is data waiting to be read from the serial port, then return
  TRUE.  If there is no data waiting to be read from the serial port, then
  return FALSE.

  @retval FALSE            There is no data waiting to be read.

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