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