audk/IntelFrameworkModulePkg/Bus/Isa/Ps2KeyboardDxe/Ps2KbdTextIn.c

/**@file
  PS/2 Keyboard  driver
  Routines that support SIMPLE_TEXT_IN protocol

Copyright (c) 2006 - 2007, 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 "Ps2Keyboard.h"

//
// function declarations
//
EFI_STATUS
EFIAPI
KeyboardEfiReset (
  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This,
  IN  BOOLEAN                         ExtendedVerification
  );

EFI_STATUS
EFIAPI
KeyboardReadKeyStroke (
  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This,
  OUT EFI_INPUT_KEY                   *Key
  );

VOID
EFIAPI
KeyboardWaitForKey (
  IN  EFI_EVENT               Event,
  IN  VOID                    *Context
  );

EFI_STATUS
KeyboardCheckForKey (
  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL *This
  );

STATIC
BOOLEAN
IsKeyRegistered (
  IN EFI_KEY_DATA  *RegsiteredData,
  IN EFI_KEY_DATA  *InputData
  )
/*++

Routine Description:

Arguments:

  RegsiteredData    - A pointer to a buffer that is filled in with the keystroke 
                      state data for the key that was registered.
  InputData         - A pointer to a buffer that is filled in with the keystroke 
                      state data for the key that was pressed.

Returns:
  TRUE              - Key be pressed matches a registered key.
  FLASE             - Match failed. 
  
--*/
;
STATIC
EFI_STATUS
KeyboardReadKeyStrokeWorker (
  IN  KEYBOARD_CONSOLE_IN_DEV           *ConsoleInDev,
  OUT EFI_KEY_DATA                      *KeyData
  )
/*++

  Routine Description:
    Reads the next keystroke from the input device. The WaitForKey Event can 
    be used to test for existance of a keystroke via WaitForEvent () call.

  Arguments:
    ConsoleInDev          - Ps2 Keyboard private structure
    KeyData               - A pointer to a buffer that is filled in with the keystroke 
                            state data for the key that was pressed.

  Returns:
    EFI_SUCCESS           - The keystroke information was returned.
    EFI_NOT_READY         - There was no keystroke data availiable.
    EFI_DEVICE_ERROR      - The keystroke information was not returned due to 
                            hardware errors.
    EFI_INVALID_PARAMETER - KeyData is NULL.                        

--*/
{
  EFI_STATUS                            Status;
  EFI_TPL                               OldTpl;
  LIST_ENTRY                            *Link;
  KEYBOARD_CONSOLE_IN_EX_NOTIFY         *CurrentNotify;
  EFI_KEY_DATA                          OriginalKeyData;
  if (KeyData == NULL) {
    return EFI_INVALID_PARAMETER;
  }
  
  //
  // Enter critical section
  //
  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);

  if (ConsoleInDev->KeyboardErr) {
    gBS->RestoreTPL (OldTpl);
    return EFI_DEVICE_ERROR;
  }
  //
  // If there's no key, just return
  //
  Status = KeyboardCheckForKey (&ConsoleInDev->ConIn);
  if (EFI_ERROR (Status)) {
    gBS->RestoreTPL (OldTpl);
    return EFI_NOT_READY;
  }
  CopyMem (&KeyData->Key, &ConsoleInDev->Key, sizeof (EFI_INPUT_KEY));

  ConsoleInDev->Key.ScanCode    = SCAN_NULL;          
  ConsoleInDev->Key.UnicodeChar = 0x0000;     
  CopyMem (&KeyData->KeyState, &ConsoleInDev->KeyState, sizeof (EFI_KEY_STATE));
                                          
  ConsoleInDev->KeyState.KeyShiftState  = EFI_SHIFT_STATE_VALID;
  ConsoleInDev->KeyState.KeyToggleState = EFI_TOGGLE_STATE_VALID;
  gBS->RestoreTPL (OldTpl);
  //
  //Switch the control value to their original characters. In KeyGetchar() the  CTRL-Alpha characters have been switched to 
  // their corresponding control value (ctrl-a = 0x0001 through ctrl-Z = 0x001A), here switch them back for notification function.
  //
  CopyMem (&OriginalKeyData, KeyData, sizeof (EFI_KEY_DATA));
  if (ConsoleInDev->Ctrled) {
    if (OriginalKeyData.Key.UnicodeChar >= 0x01 && OriginalKeyData.Key.UnicodeChar <= 0x1A) {
      if (ConsoleInDev->CapsLock) {
        OriginalKeyData.Key.UnicodeChar = (CHAR16)(OriginalKeyData.Key.UnicodeChar + 'A' - 1);
      } else {
        OriginalKeyData.Key.UnicodeChar = (CHAR16)(OriginalKeyData.Key.UnicodeChar + 'a' - 1);
      } 
    }
  }
  //
  // Invoke notification functions if exist
  //
  for (Link = ConsoleInDev->NotifyList.ForwardLink; Link != &ConsoleInDev->NotifyList; Link = Link->ForwardLink) {
    CurrentNotify = CR (
                      Link, 
                      KEYBOARD_CONSOLE_IN_EX_NOTIFY, 
                      NotifyEntry, 
                      KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE
                      );
    if (IsKeyRegistered (&CurrentNotify->KeyData, &OriginalKeyData)) { 
      CurrentNotify->KeyNotificationFn (&OriginalKeyData);
    }
  }

  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
KeyboardEfiReset (
  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This,
  IN  BOOLEAN                         ExtendedVerification
  )
/*++

Routine Description:

  Implement SIMPLE_TEXT_IN.Reset()
  Perform 8042 controller and keyboard initialization

Arguments:

Returns:

--*/
// GC_TODO:    This - add argument and description to function comment
// GC_TODO:    ExtendedVerification - add argument and description to function comment
// GC_TODO:    EFI_DEVICE_ERROR - add return value to function comment
// GC_TODO:    EFI_DEVICE_ERROR - add return value to function comment
// GC_TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_STATUS              Status;
  KEYBOARD_CONSOLE_IN_DEV *ConsoleIn;
  EFI_TPL                 OldTpl;

  ConsoleIn = KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This);
  if (ConsoleIn->KeyboardErr) {
    return EFI_DEVICE_ERROR;
  }

  REPORT_STATUS_CODE_WITH_DEVICE_PATH (
    EFI_PROGRESS_CODE,
    EFI_PERIPHERAL_KEYBOARD | EFI_P_PC_RESET,
    ConsoleIn->DevicePath
    );

  //
  // Enter critical section
  //
  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);

  //
  // Call InitKeyboard to initialize the keyboard
  //
  Status = InitKeyboard (ConsoleIn, ExtendedVerification);
  if (EFI_ERROR (Status)) {
    //
    // Leave critical section and return
    //
    gBS->RestoreTPL (OldTpl);
    return EFI_DEVICE_ERROR;
  }
  //
  // Clear the status of ConsoleIn.Key
  //
  ConsoleIn->Key.ScanCode     = SCAN_NULL;
  ConsoleIn->Key.UnicodeChar  = 0x0000;

  //
  // Leave critical section and return
  //
  gBS->RestoreTPL (OldTpl);

  //
  // Report the status If a stuck key was detected
  //
  if (KeyReadStatusRegister (ConsoleIn) & 0x01) {
    REPORT_STATUS_CODE_WITH_DEVICE_PATH (
      EFI_ERROR_CODE | EFI_ERROR_MINOR,
      EFI_PERIPHERAL_KEYBOARD | EFI_P_KEYBOARD_EC_STUCK_KEY,
      ConsoleIn->DevicePath
      );
  }
  //
  // Report the status If keyboard is locked
  //
  if (!(KeyReadStatusRegister (ConsoleIn) & 0x10)) {
    REPORT_STATUS_CODE_WITH_DEVICE_PATH (
      EFI_ERROR_CODE | EFI_ERROR_MINOR,
      EFI_PERIPHERAL_KEYBOARD | EFI_P_KEYBOARD_EC_LOCKED,
      ConsoleIn->DevicePath
      );
  }

  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
KeyboardReadKeyStroke (
  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This,
  OUT EFI_INPUT_KEY                   *Key
  )
/*++

Routine Description:

  Implement SIMPLE_TEXT_IN.ReadKeyStroke().
  Retrieve key values for driver user.

Arguments:

Returns:

--*/
// GC_TODO:    This - add argument and description to function comment
// GC_TODO:    Key - add argument and description to function comment
// GC_TODO:    EFI_DEVICE_ERROR - add return value to function comment
// GC_TODO:    EFI_NOT_READY - add return value to function comment
// GC_TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_STATUS              Status;
  KEYBOARD_CONSOLE_IN_DEV *ConsoleIn;
  EFI_KEY_DATA            KeyData;

  ConsoleIn = KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This);
  Status = KeyboardReadKeyStrokeWorker (ConsoleIn, &KeyData);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  CopyMem (Key, &KeyData.Key, sizeof (EFI_INPUT_KEY));
  return EFI_SUCCESS;
  
}

VOID
EFIAPI
KeyboardWaitForKey (
  IN  EFI_EVENT               Event,
  IN  VOID                    *Context
  )
/*++

Routine Description:

  Event notification function for SIMPLE_TEXT_IN.WaitForKey event
  Signal the event if there is key available

Arguments:

Returns:

--*/
// GC_TODO:    Event - add argument and description to function comment
// GC_TODO:    Context - add argument and description to function comment
{
  EFI_TPL                 OldTpl;
  KEYBOARD_CONSOLE_IN_DEV *ConsoleIn;

  ConsoleIn = KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (Context);

  //
  // Enter critical section
  //
  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);

  if (ConsoleIn->KeyboardErr) {
    //
    // Leave critical section and return
    //
    gBS->RestoreTPL (OldTpl);
    return ;
  }
  //
  // Someone is waiting on the keyboard event, if there's
  // a key pending, signal the event
  //
  if (!EFI_ERROR (KeyboardCheckForKey (Context))) {
    gBS->SignalEvent (Event);
  }
  //
  // Leave critical section and return
  //
  gBS->RestoreTPL (OldTpl);

  return ;
}

EFI_STATUS
KeyboardCheckForKey (
  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL *This
  )
/*++

Routine Description:

  GC_TODO: Add function description

Arguments:

  This  - GC_TODO: add argument description

Returns:

  EFI_SUCCESS - GC_TODO: Add description for return value

--*/
{
  KEYBOARD_CONSOLE_IN_DEV *ConsoleIn;

  ConsoleIn = KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This);

  //
  // If ready to read next key, check it
  //
  if (ConsoleIn->Key.ScanCode == SCAN_NULL && ConsoleIn->Key.UnicodeChar == 0x00) {
    return KeyGetchar (ConsoleIn);
  }

  return EFI_SUCCESS;
}

STATIC
BOOLEAN
IsKeyRegistered (
  IN EFI_KEY_DATA  *RegsiteredData,
  IN EFI_KEY_DATA  *InputData
  )
/*++

Routine Description:

Arguments:

  RegsiteredData    - A pointer to a buffer that is filled in with the keystroke 
                      state data for the key that was registered.
  InputData         - A pointer to a buffer that is filled in with the keystroke 
                      state data for the key that was pressed.

Returns:
  TRUE              - Key be pressed matches a registered key.
  FLASE             - Match failed. 
  
--*/
{
  ASSERT (RegsiteredData != NULL && InputData != NULL);
  
  if ((RegsiteredData->Key.ScanCode    != InputData->Key.ScanCode) ||
      (RegsiteredData->Key.UnicodeChar != InputData->Key.UnicodeChar)) {
    return FALSE;  
  }      
  
  //
  // Assume KeyShiftState/KeyToggleState = 0 in Registered key data means these state could be ignored.
  //
  if (RegsiteredData->KeyState.KeyShiftState != 0 &&
      RegsiteredData->KeyState.KeyShiftState != InputData->KeyState.KeyShiftState) {
    return FALSE;    
  }   
  if (RegsiteredData->KeyState.KeyToggleState != 0 &&
      RegsiteredData->KeyState.KeyToggleState != InputData->KeyState.KeyToggleState) {
    return FALSE;    
  }     
  
  return TRUE;

}

VOID
EFIAPI
KeyboardWaitForKeyEx (
  IN  EFI_EVENT               Event,
  IN  VOID                    *Context
  )
/*++

Routine Description:

  Event notification function for SIMPLE_TEXT_INPUT_EX_PROTOCOL.WaitForKeyEx event
  Signal the event if there is key available

Arguments:

Returns:

--*/
{
  KEYBOARD_CONSOLE_IN_DEV               *ConsoleInDev;

  ConsoleInDev = TEXT_INPUT_EX_KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (Context); 
  KeyboardWaitForKey (Event, &ConsoleInDev->ConIn);
  
}

EFI_STATUS
EFIAPI
KeyboardEfiResetEx (
  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
  IN BOOLEAN                            ExtendedVerification
  )
/*++

  Routine Description:
    Reset the input device and optionaly run diagnostics

  Arguments:
    This                 - Protocol instance pointer.
    ExtendedVerification - Driver may perform diagnostics on reset.

  Returns:
    EFI_SUCCESS           - The device was reset.
    EFI_DEVICE_ERROR      - The device is not functioning properly and could 
                            not be reset.

--*/
{
  EFI_STATUS                            Status;
  KEYBOARD_CONSOLE_IN_DEV               *ConsoleInDev;
  EFI_TPL                               OldTpl;

  ConsoleInDev = TEXT_INPUT_EX_KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This); 
  if (ConsoleInDev->KeyboardErr) {
    return EFI_DEVICE_ERROR;
  }

  Status = ConsoleInDev->ConIn.Reset (
                                 &ConsoleInDev->ConIn, 
                                 ExtendedVerification
                                 );
  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);

  ConsoleInDev->KeyState.KeyShiftState  = EFI_SHIFT_STATE_VALID;
  ConsoleInDev->KeyState.KeyToggleState = EFI_TOGGLE_STATE_VALID;

  gBS->RestoreTPL (OldTpl);  
  
  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
KeyboardReadKeyStrokeEx (
  IN  EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL *This,
  OUT EFI_KEY_DATA                      *KeyData
  )
/*++

  Routine Description:
    Reads the next keystroke from the input device. The WaitForKey Event can 
    be used to test for existance of a keystroke via WaitForEvent () call.

  Arguments:
    This       - Protocol instance pointer.
    KeyData    - A pointer to a buffer that is filled in with the keystroke 
                 state data for the key that was pressed.

  Returns:
    EFI_SUCCESS           - The keystroke information was returned.
    EFI_NOT_READY         - There was no keystroke data availiable.
    EFI_DEVICE_ERROR      - The keystroke information was not returned due to 
                            hardware errors.
    EFI_INVALID_PARAMETER - KeyData is NULL.                        

--*/
{
  KEYBOARD_CONSOLE_IN_DEV               *ConsoleInDev;

  if (KeyData == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  ConsoleInDev = TEXT_INPUT_EX_KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This);
  return KeyboardReadKeyStrokeWorker (ConsoleInDev, KeyData);
  
}

EFI_STATUS
EFIAPI
KeyboardSetState (
  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
  IN EFI_KEY_TOGGLE_STATE               *KeyToggleState
  )
/*++

  Routine Description:
    Set certain state for the input device.

  Arguments:
    This              - Protocol instance pointer.
    KeyToggleState    - A pointer to the EFI_KEY_TOGGLE_STATE to set the 
                        state for the input device.

  Returns:
    EFI_SUCCESS           - The device state was set successfully.
    EFI_DEVICE_ERROR      - The device is not functioning correctly and could 
                            not have the setting adjusted.
    EFI_UNSUPPORTED       - The device does not have the ability to set its state.
    EFI_INVALID_PARAMETER - KeyToggleState is NULL.                       

--*/   
{
  EFI_STATUS                            Status;
  KEYBOARD_CONSOLE_IN_DEV               *ConsoleInDev;
  EFI_TPL                               OldTpl;

  if (KeyToggleState == NULL) {
    return EFI_INVALID_PARAMETER;
  }
  
  ConsoleInDev = TEXT_INPUT_EX_KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This);

  //
  // Enter critical section
  //
  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);

  if (ConsoleInDev->KeyboardErr) {
    Status = EFI_DEVICE_ERROR;
    goto Exit;
  }

  if (((ConsoleInDev->KeyState.KeyToggleState & EFI_TOGGLE_STATE_VALID) != EFI_TOGGLE_STATE_VALID) ||
      ((*KeyToggleState & EFI_TOGGLE_STATE_VALID) != EFI_TOGGLE_STATE_VALID)) {
    Status = EFI_UNSUPPORTED;
    goto Exit;
  }
  
  //
  // Update the status light
  //
  ConsoleInDev->ScrollLock = FALSE;
  ConsoleInDev->NumLock    = FALSE;
  ConsoleInDev->CapsLock   = FALSE;

  if ((*KeyToggleState & EFI_SCROLL_LOCK_ACTIVE) == EFI_SCROLL_LOCK_ACTIVE) {
    ConsoleInDev->ScrollLock = TRUE;
  } 
  if ((*KeyToggleState & EFI_NUM_LOCK_ACTIVE) == EFI_NUM_LOCK_ACTIVE) {
    ConsoleInDev->NumLock = TRUE;
  }
  if ((*KeyToggleState & EFI_CAPS_LOCK_ACTIVE) == EFI_CAPS_LOCK_ACTIVE) {
    ConsoleInDev->CapsLock = TRUE;
  }

  Status = UpdateStatusLights (ConsoleInDev);
  if (EFI_ERROR (Status)) {
    Status = EFI_DEVICE_ERROR;    
  }

  ConsoleInDev->KeyState.KeyToggleState = *KeyToggleState;
  
Exit:   
  //
  // Leave critical section and return
  //
  gBS->RestoreTPL (OldTpl);

  return Status;

}
EFI_STATUS
EFIAPI
KeyboardRegisterKeyNotify (
  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
  IN EFI_KEY_DATA                       *KeyData,
  IN EFI_KEY_NOTIFY_FUNCTION            KeyNotificationFunction,
  OUT EFI_HANDLE                        *NotifyHandle
  )
/*++

  Routine Description:
    Register a notification function for a particular keystroke for the input device.

  Arguments:
    This                    - Protocol instance pointer.
    KeyData                 - A pointer to a buffer that is filled in with the keystroke 
                              information data for the key that was pressed.
    KeyNotificationFunction - Points to the function to be called when the key 
                              sequence is typed specified by KeyData.                        
    NotifyHandle            - Points to the unique handle assigned to the registered notification.                          

  Returns:
    EFI_SUCCESS             - The notification function was registered successfully.
    EFI_OUT_OF_RESOURCES    - Unable to allocate resources for necesssary data structures.
    EFI_INVALID_PARAMETER   - KeyData or NotifyHandle is NULL.                       
                              
--*/   
{
  EFI_STATUS                            Status;
  KEYBOARD_CONSOLE_IN_DEV               *ConsoleInDev;
  EFI_TPL                               OldTpl;
  LIST_ENTRY                            *Link;
  KEYBOARD_CONSOLE_IN_EX_NOTIFY         *CurrentNotify;  
  KEYBOARD_CONSOLE_IN_EX_NOTIFY         *NewNotify;

  if (KeyData == NULL || NotifyHandle == NULL || KeyNotificationFunction == NULL) {
    return EFI_INVALID_PARAMETER;
  }
  
  ConsoleInDev = TEXT_INPUT_EX_KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This);

  //
  // Enter critical section
  //
  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);

  //
  // Return EFI_SUCCESS if the (KeyData, NotificationFunction) is already registered.
  //
  for (Link = ConsoleInDev->NotifyList.ForwardLink; Link != &ConsoleInDev->NotifyList; Link = Link->ForwardLink) {
    CurrentNotify = CR (
                      Link, 
                      KEYBOARD_CONSOLE_IN_EX_NOTIFY, 
                      NotifyEntry, 
                      KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE
                      );
    if (IsKeyRegistered (&CurrentNotify->KeyData, KeyData)) { 
      if (CurrentNotify->KeyNotificationFn == KeyNotificationFunction) {
        *NotifyHandle = CurrentNotify->NotifyHandle;        
        Status = EFI_SUCCESS;
        goto Exit;
      }
    }
  }    
  
  //
  // Allocate resource to save the notification function
  //  
  NewNotify = (KEYBOARD_CONSOLE_IN_EX_NOTIFY *) AllocateZeroPool (sizeof (KEYBOARD_CONSOLE_IN_EX_NOTIFY));
  if (NewNotify == NULL) {
    Status = EFI_OUT_OF_RESOURCES;
    goto Exit;
  }

  NewNotify->Signature         = KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE;     
  NewNotify->KeyNotificationFn = KeyNotificationFunction;
  CopyMem (&NewNotify->KeyData, KeyData, sizeof (EFI_KEY_DATA));
  InsertTailList (&ConsoleInDev->NotifyList, &NewNotify->NotifyEntry);

  //
  // Use gSimpleTextInExNotifyGuid to get a valid EFI_HANDLE
  //  
  Status = gBS->InstallMultipleProtocolInterfaces (
                  &NewNotify->NotifyHandle,
                  &gSimpleTextInExNotifyGuid,
                  NULL,
                  NULL
                  );
  ASSERT_EFI_ERROR (Status);
  *NotifyHandle                = NewNotify->NotifyHandle;  
  Status                       = EFI_SUCCESS;

Exit:
  //
  // Leave critical section and return
  //
  gBS->RestoreTPL (OldTpl);
  return Status;  

}

EFI_STATUS
EFIAPI
KeyboardUnregisterKeyNotify (
  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
  IN EFI_HANDLE                         NotificationHandle
  )
/*++

  Routine Description:
    Remove a registered notification function from a particular keystroke.

  Arguments:
    This                    - Protocol instance pointer.    
    NotificationHandle      - The handle of the notification function being unregistered.

  Returns:
    EFI_SUCCESS             - The notification function was unregistered successfully.
    EFI_INVALID_PARAMETER   - The NotificationHandle is invalid.
    EFI_NOT_FOUND           - Can not find the matching entry in database.  
                              
--*/   
{
  EFI_STATUS                            Status;
  KEYBOARD_CONSOLE_IN_DEV               *ConsoleInDev;
  EFI_TPL                               OldTpl;
  LIST_ENTRY                            *Link;
  KEYBOARD_CONSOLE_IN_EX_NOTIFY         *CurrentNotify;    

  if (NotificationHandle == NULL) {
    return EFI_INVALID_PARAMETER;
  } 
  
  Status = gBS->OpenProtocol (
                  NotificationHandle,
                  &gSimpleTextInExNotifyGuid,
                  NULL,
                  NULL,
                  NULL,
                  EFI_OPEN_PROTOCOL_TEST_PROTOCOL
                  );
  if (EFI_ERROR (Status)) {
    return EFI_INVALID_PARAMETER;
  }

  ConsoleInDev = TEXT_INPUT_EX_KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This);
  
  //
  // Enter critical section
  //
  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);  

  for (Link = ConsoleInDev->NotifyList.ForwardLink; Link != &ConsoleInDev->NotifyList; Link = Link->ForwardLink) {
    CurrentNotify = CR (
                      Link, 
                      KEYBOARD_CONSOLE_IN_EX_NOTIFY, 
                      NotifyEntry, 
                      KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE
                      );       
    if (CurrentNotify->NotifyHandle == NotificationHandle) {
      //
      // Remove the notification function from NotifyList and free resources
      //
      RemoveEntryList (&CurrentNotify->NotifyEntry);      
      Status = gBS->UninstallMultipleProtocolInterfaces (
                      CurrentNotify->NotifyHandle,
                      &gSimpleTextInExNotifyGuid,
                      NULL,
                      NULL
                      );
      ASSERT_EFI_ERROR (Status);
      gBS->FreePool (CurrentNotify);            
      Status = EFI_SUCCESS;
      goto Exit;
    }
  }

  //
  // Can not find the specified Notification Handle
  //
  Status = EFI_NOT_FOUND;
Exit:
  //
  // Leave critical section and return
  //
  gBS->RestoreTPL (OldTpl);
  return Status;
}