MdePkg/Library/BaseSerialPortLibNull/BaseSerialPortLibNull.c

   1 /** @file
   2   Null Serial Port library instance with empty functions.
   3
   4   Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9
  10 #include <Base.h>
  11 #include <Library/SerialPortLib.h>
  12
  13 /**
  14   Initialize the serial device hardware.
  15
  16   If no initialization is required, then return RETURN_SUCCESS.
  17   If the serial device was successfully initialized, then return RETURN_SUCCESS.
  18   If the serial device could not be initialized, then return RETURN_DEVICE_ERROR.
  19
  20   @retval RETURN_SUCCESS        The serial device was initialized.
  21   @retval RETURN_DEVICE_ERROR   The serial device could not be initialized.
  22
  23 **/
  24 RETURN_STATUS
  25 EFIAPI
  26 SerialPortInitialize (
  27   VOID
  28   )
  29 {
  30   return RETURN_SUCCESS;
  31 }
  32
  33 /**
  34   Write data from buffer to serial device.
  35
  36   Writes NumberOfBytes data bytes from Buffer to the serial device.
  37   The number of bytes actually written to the serial device is returned.
  38   If the return value is less than NumberOfBytes, then the write operation failed.
  39   If Buffer is NULL, then ASSERT().
  40   If NumberOfBytes is zero, then return 0.
  41
  42   @param  Buffer           The pointer to the data buffer to be written.
  43   @param  NumberOfBytes    The number of bytes to written to the serial device.
  44
  45   @retval 0                NumberOfBytes is 0.
  46   @retval >0               The number of bytes written to the serial device.
  47                            If this value is less than NumberOfBytes, then the write operation failed.
  48
  49 **/
  50 UINTN
  51 EFIAPI
  52 SerialPortWrite (
  53   IN UINT8     *Buffer,
  54   IN UINTN     NumberOfBytes
  55 )
  56 {
  57   return 0;
  58 }
  59
  60
  61 /**
  62   Read data from serial device and save the datas in buffer.
  63
  64   Reads NumberOfBytes data bytes from a serial device into the buffer
  65   specified by Buffer. The number of bytes actually read is returned.
  66   If the return value is less than NumberOfBytes, then the rest operation failed.
  67   If Buffer is NULL, then ASSERT().
  68   If NumberOfBytes is zero, then return 0.
  69
  70   @param  Buffer           The pointer to the data buffer to store the data read from the serial device.
  71   @param  NumberOfBytes    The number of bytes which will be read.
  72
  73   @retval 0                Read data failed; No data is to be read.
  74   @retval >0               The actual number of bytes read from serial device.
  75
  76 **/
  77 UINTN
  78 EFIAPI
  79 SerialPortRead (
  80   OUT UINT8     *Buffer,
  81   IN  UINTN     NumberOfBytes
  82 )
  83 {
  84   return 0;
  85 }
  86
  87 /**
  88   Polls a serial device to see if there is any data waiting to be read.
  89
  90   Polls a serial device to see if there is any data waiting to be read.
  91   If there is data waiting to be read from the serial device, then TRUE is returned.
  92   If there is no data waiting to be read from the serial device, then FALSE is returned.
  93
  94   @retval TRUE             Data is waiting to be read from the serial device.
  95   @retval FALSE            There is no data waiting to be read from the serial device.
  96
  97 **/
  98 BOOLEAN
  99 EFIAPI
 100 SerialPortPoll (
 101   VOID
 102   )
 103 {
 104   return FALSE;
 105 }
 106
 107 /**
 108   Sets the control bits on a serial device.
 109
 110   @param Control                Sets the bits of Control that are settable.
 111
 112   @retval RETURN_SUCCESS        The new control bits were set on the serial device.
 113   @retval RETURN_UNSUPPORTED    The serial device does not support this operation.
 114   @retval RETURN_DEVICE_ERROR   The serial device is not functioning correctly.
 115
 116 **/
 117 RETURN_STATUS
 118 EFIAPI
 119 SerialPortSetControl (
 120   IN UINT32 Control
 121   )
 122 {
 123   return RETURN_UNSUPPORTED;
 124 }
 125
 126 /**
 127   Retrieve the status of the control bits on a serial device.
 128
 129   @param Control                A pointer to return the current control signals from the serial device.
 130
 131   @retval RETURN_SUCCESS        The control bits were read from the serial device.
 132   @retval RETURN_UNSUPPORTED    The serial device does not support this operation.
 133   @retval RETURN_DEVICE_ERROR   The serial device is not functioning correctly.
 134
 135 **/
 136 RETURN_STATUS
 137 EFIAPI
 138 SerialPortGetControl (
 139   OUT UINT32 *Control
 140   )
 141 {
 142   return RETURN_UNSUPPORTED;
 143 }
 144
 145 /**
 146   Sets the baud rate, receive FIFO depth, transmit/receice time out, parity,
 147   data bits, and stop bits on a serial device.
 148
 149   @param BaudRate           The requested baud rate. A BaudRate value of 0 will use the
 150                             device's default interface speed.
 151                             On output, the value actually set.
 152   @param ReveiveFifoDepth   The requested depth of the FIFO on the receive side of the
 153                             serial interface. A ReceiveFifoDepth value of 0 will use
 154                             the device's default FIFO depth.
 155                             On output, the value actually set.
 156   @param Timeout            The requested time out for a single character in microseconds.
 157                             This timeout applies to both the transmit and receive side of the
 158                             interface. A Timeout value of 0 will use the device's default time
 159                             out value.
 160                             On output, the value actually set.
 161   @param Parity             The type of parity to use on this serial device. A Parity value of
 162                             DefaultParity will use the device's default parity value.
 163                             On output, the value actually set.
 164   @param DataBits           The number of data bits to use on the serial device. A DataBits
 165                             vaule of 0 will use the device's default data bit setting.
 166                             On output, the value actually set.
 167   @param StopBits           The number of stop bits to use on this serial device. A StopBits
 168                             value of DefaultStopBits will use the device's default number of
 169                             stop bits.
 170                             On output, the value actually set.
 171
 172   @retval RETURN_SUCCESS            The new attributes were set on the serial device.
 173   @retval RETURN_UNSUPPORTED        The serial device does not support this operation.
 174   @retval RETURN_INVALID_PARAMETER  One or more of the attributes has an unsupported value.
 175   @retval RETURN_DEVICE_ERROR       The serial device is not functioning correctly.
 176
 177 **/
 178 RETURN_STATUS
 179 EFIAPI
 180 SerialPortSetAttributes (
 181   IN OUT UINT64             *BaudRate,
 182   IN OUT UINT32             *ReceiveFifoDepth,
 183   IN OUT UINT32             *Timeout,
 184   IN OUT EFI_PARITY_TYPE    *Parity,
 185   IN OUT UINT8              *DataBits,
 186   IN OUT EFI_STOP_BITS_TYPE *StopBits
 187   )
 188 {
 189   return RETURN_UNSUPPORTED;
 190 }
 191