MdeModulePkg/TerminalDxe: Fix driver model bug

TerminalDxe driver contains bugs in its DriverBindingStart():
1. It cannot be started AGAIN using a different terminal type;
2. It doesn't install SimpleTextInput/SimpleTextOut when
   ConIn/ConOut doesn't contain its device path. The check is
   duplicated of the same logic in ConPlatform driver and can
   be removed.

The patch optimized the code to remove the unnecessary
gEfiCallerIdGuid protocol installation.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>

MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c

@@ -264,154 +264,6 @@ TerminalDriverBindingSupported (
   return Status;
 }
 
-/**
-  Build the terminal device path for the child device according to the
-  terminal type.
-
-  @param  ParentDevicePath         Parent device path.
-  @param  RemainingDevicePath      A specific child device.
-
-  @return The child device path built.
-
-**/
-EFI_DEVICE_PATH_PROTOCOL*
-EFIAPI
-BuildTerminalDevpath  (
-  IN EFI_DEVICE_PATH_PROTOCOL       *ParentDevicePath,
-  IN EFI_DEVICE_PATH_PROTOCOL       *RemainingDevicePath
-  )
-{
-  EFI_DEVICE_PATH_PROTOCOL          *TerminalDevicePath;
-  TERMINAL_TYPE                     TerminalType;
-  VENDOR_DEVICE_PATH                *Node;
-  EFI_STATUS                        Status;
-
-  TerminalDevicePath = NULL;
-
-  //
-  // Use the RemainingDevicePath to determine the terminal type
-  //
-  Node = (VENDOR_DEVICE_PATH *) RemainingDevicePath;
-  if (Node == NULL) {
-    TerminalType = PcdGet8 (PcdDefaultTerminalType);
-
-  } else if (CompareGuid (&Node->Guid, &gEfiPcAnsiGuid)) {
-
-    TerminalType = TerminalTypePcAnsi;
-
-  } else if (CompareGuid (&Node->Guid, &gEfiVT100Guid)) {
-
-    TerminalType = TerminalTypeVt100;
-
-  } else if (CompareGuid (&Node->Guid, &gEfiVT100PlusGuid)) {
-
-    TerminalType = TerminalTypeVt100Plus;
-
-  } else if (CompareGuid (&Node->Guid, &gEfiVTUTF8Guid)) {
-
-    TerminalType = TerminalTypeVtUtf8;
-
-  } else if (CompareGuid (&Node->Guid, &gEfiTtyTermGuid)) {
-
-    TerminalType = TerminalTypeTtyTerm;
-
-  } else {
-    return NULL;
-  }
-
-  //
-  // Build the device path for the child device
-  //
-  Status = SetTerminalDevicePath (
-            TerminalType,
-            ParentDevicePath,
-            &TerminalDevicePath
-            );
-  if (EFI_ERROR (Status)) {
-    return NULL;
-  }
-  return TerminalDevicePath;
-}
-
-/**
-  Compare a device path data structure to that of all the nodes of a
-  second device path instance.
-
-  @param  Multi          A pointer to a multi-instance device path data structure.
-  @param  Single         A pointer to a single-instance device path data structure.
-
-  @retval TRUE           If the Single is contained within Multi.
-  @retval FALSE          The Single is not match within Multi.
-
-**/
-BOOLEAN
-MatchDevicePaths (
-  IN  EFI_DEVICE_PATH_PROTOCOL  *Multi,
-  IN  EFI_DEVICE_PATH_PROTOCOL  *Single
-  )
-{
-  EFI_DEVICE_PATH_PROTOCOL  *DevicePath;
-  EFI_DEVICE_PATH_PROTOCOL  *DevicePathInst;
-  UINTN                     Size;
-
-  DevicePath      = Multi;
-  DevicePathInst  = GetNextDevicePathInstance (&DevicePath, &Size);
-  //
-  // Search for the match of 'Single' in 'Multi'
-  //
-  while (DevicePathInst != NULL) {
-    //
-    // If the single device path is found in multiple device paths,
-    // return success
-    //
-    if (CompareMem (Single, DevicePathInst, Size) == 0) {
-      FreePool (DevicePathInst);
-      return TRUE;
-    }
-
-    FreePool (DevicePathInst);
-    DevicePathInst = GetNextDevicePathInstance (&DevicePath, &Size);
-  }
-
-  return FALSE;
-}
-
-/**
-  Check whether the terminal device path is in the global variable.
-
-  @param  VariableName          Pointer to one global variable.
-  @param  TerminalDevicePath    Pointer to the terminal device's device path.
-
-  @retval TRUE                  The devcie is in the global variable.
-  @retval FALSE                 The devcie is not in the global variable.
-
-**/
-BOOLEAN
-IsTerminalInConsoleVariable (
-  IN CHAR16                    *VariableName,
-  IN EFI_DEVICE_PATH_PROTOCOL  *TerminalDevicePath
-  )
-{
-  EFI_DEVICE_PATH_PROTOCOL  *Variable;
-  BOOLEAN                   ReturnFlag;
-
-  //
-  // Get global variable and its size according to the name given.
-  //
-  GetEfiGlobalVariable2 (VariableName, (VOID**)&Variable, NULL);
-  if (Variable == NULL) {
-    return FALSE;
-  }
-
-  //
-  // Check whether the terminal device path is one of the variable instances.
-  //
-  ReturnFlag = MatchDevicePaths (Variable, TerminalDevicePath);
-
-  FreePool (Variable);
-
-  return ReturnFlag;
-}
 
 /**
   Free notify functions list.
@@ -616,31 +468,19 @@ TerminalDriverBindingStart (
   EFI_STATUS                          Status;
   EFI_SERIAL_IO_PROTOCOL              *SerialIo;
   EFI_DEVICE_PATH_PROTOCOL            *ParentDevicePath;
-  VENDOR_DEVICE_PATH                  *Node;
+  EFI_DEVICE_PATH_PROTOCOL            *Vendor;
+  EFI_HANDLE                          SerialIoHandle;
   EFI_SERIAL_IO_MODE                  *Mode;
   UINTN                               SerialInTimeOut;
   TERMINAL_DEV                        *TerminalDevice;
-  TERMINAL_TYPE                       TerminalType;
+  UINT8                               TerminalType;
   EFI_OPEN_PROTOCOL_INFORMATION_ENTRY *OpenInfoBuffer;
   UINTN                               EntryCount;
   UINTN                               Index;
-  EFI_DEVICE_PATH_PROTOCOL            *DevicePath;
   EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL     *SimpleTextOutput;
   EFI_SIMPLE_TEXT_INPUT_PROTOCOL      *SimpleTextInput;
-  BOOLEAN                             ConInSelected;
+  EFI_UNICODE_STRING_TABLE            *ControllerNameTable;
-  BOOLEAN                             ConOutSelected;
-  BOOLEAN                             NullRemaining;
-  BOOLEAN                             SimTxtInInstalled;
-  BOOLEAN                             SimTxtOutInstalled;
-  BOOLEAN                             FirstEnter;
 
-  TerminalDevice     = NULL;
-  ConInSelected      = FALSE;
-  ConOutSelected     = FALSE;
-  NullRemaining      = FALSE;
-  SimTxtInInstalled  = FALSE;
-  SimTxtOutInstalled = FALSE;
-  FirstEnter         = FALSE;
   //
   // Get the Device Path Protocol to build the device path of the child device
   //
@@ -652,9 +492,7 @@ TerminalDriverBindingStart (
                   Controller,
                   EFI_OPEN_PROTOCOL_BY_DRIVER
                   );
-  if (EFI_ERROR (Status) && Status != EFI_ALREADY_STARTED) {
+  ASSERT ((Status == EFI_SUCCESS) || (Status == EFI_ALREADY_STARTED));
-    return Status;
-  }
 
   //
   // Open the Serial I/O Protocol BY_DRIVER.  It might already be started.
@@ -667,95 +505,37 @@ TerminalDriverBindingStart (
                   Controller,
                   EFI_OPEN_PROTOCOL_BY_DRIVER
                   );
-  if (EFI_ERROR (Status) && Status != EFI_ALREADY_STARTED) {
+  ASSERT ((Status == EFI_SUCCESS) || (Status == EFI_ALREADY_STARTED));
-    return Status;
-  }
-
-  if (Status != EFI_ALREADY_STARTED) {
-    //
-    // the serial I/O protocol never be opened before, it is the first
-    // time to start the serial Io controller
-    //
-    FirstEnter = TRUE;
-  }
-
-  //
-  // Serial I/O is not already open by this driver, then tag the handle
-  // with the Terminal Driver GUID and update the ConInDev, ConOutDev, and
-  // StdErrDev variables with the list of possible terminal types on this
-  // serial port.
-  //
-  Status = gBS->OpenProtocol (
-                  Controller,
-                  &gEfiCallerIdGuid,
-                  NULL,
-                  This->DriverBindingHandle,
-                  Controller,
-                  EFI_OPEN_PROTOCOL_TEST_PROTOCOL
-                  );
-  if (EFI_ERROR (Status)) {
-    Status = gBS->InstallMultipleProtocolInterfaces (
-                    &Controller,
-                    &gEfiCallerIdGuid,
-                    DuplicateDevicePath (ParentDevicePath),
-                    NULL
-                    );
-    if (EFI_ERROR (Status)) {
-      goto Error;
-    }
 
   if (!IsHotPlugDevice (ParentDevicePath)) {
     //
     // if the serial device is a hot plug device, do not update the
     // ConInDev, ConOutDev, and StdErrDev variables.
     //
-      TerminalUpdateConsoleDevVariable (L"ConInDev", ParentDevicePath);
+    TerminalUpdateConsoleDevVariable (EFI_CON_IN_DEV_VARIABLE_NAME, ParentDevicePath);
-      TerminalUpdateConsoleDevVariable (L"ConOutDev", ParentDevicePath);
+    TerminalUpdateConsoleDevVariable (EFI_CON_OUT_DEV_VARIABLE_NAME, ParentDevicePath);
-      TerminalUpdateConsoleDevVariable (L"ErrOutDev", ParentDevicePath);
+    TerminalUpdateConsoleDevVariable (EFI_ERR_OUT_DEV_VARIABLE_NAME, ParentDevicePath);
-    }
   }
 
   //
-  // Check the requirement for the SimpleTxtIn and SimpleTxtOut protocols
+  // Do not create any child for END remaining device path.
-  //
-  // Simple In/Out Protocol will not be installed onto the handle if the
-  // device path to the handle is not present in the ConIn/ConOut
-  // environment variable. But If RemainingDevicePath is NULL, then always
-  // produce both Simple In and Simple Text Output Protocols. This is required
-  // for the connect all sequences to make sure all possible consoles are
-  // produced no matter what the current values of ConIn, ConOut, or StdErr are.
   //
+  if ((RemainingDevicePath != NULL) && IsDevicePathEnd (RemainingDevicePath)) {
+    return EFI_SUCCESS;
+  }
+
+  if (Status == EFI_ALREADY_STARTED) {
+
     if (RemainingDevicePath == NULL) {
-    NullRemaining = TRUE;
-  }
-
-  DevicePath = BuildTerminalDevpath (ParentDevicePath, RemainingDevicePath);
-  if (DevicePath != NULL) {
-    ConInSelected  = IsTerminalInConsoleVariable (L"ConIn", DevicePath);
-    ConOutSelected = IsTerminalInConsoleVariable (L"ConOut", DevicePath);
-    FreePool (DevicePath);
-  } else {
-    goto Error;
-  }
       //
-  // Not create the child terminal handle if both Simple In/In Ex and
+      // If RemainingDevicePath is NULL or is the End of Device Path Node
-  // Simple text Out protocols are not required to be published
       //
-  if ((!ConInSelected)&&(!ConOutSelected)&&(!NullRemaining)) {
+      return EFI_SUCCESS;
-    goto Error;
     }
 
     //
-  // create the child terminal handle during first entry
+    // This driver can only produce one child per serial port.
-  //
+    // Change its terminal type as remaining device path requests.
-  if (FirstEnter) {
-    //
-    // First enther the start function
-    //
-    FirstEnter = FALSE;
-    //
-    // Make sure a child handle does not already exist.  This driver can only
-    // produce one child per serial port.
     //
     Status = gBS->OpenProtocolInformation (
                     Controller,
@@ -764,40 +544,60 @@ TerminalDriverBindingStart (
                     &EntryCount
                     );
     if (!EFI_ERROR (Status)) {
-      Status = EFI_SUCCESS;
+      Status = EFI_NOT_FOUND;
       for (Index = 0; Index < EntryCount; Index++) {
         if ((OpenInfoBuffer[Index].Attributes & EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER) != 0) {
-          Status = EFI_ALREADY_STARTED;
+          Status = gBS->OpenProtocol (
-        }
+                          OpenInfoBuffer[Index].ControllerHandle,
-      }
+                          &gEfiSimpleTextInProtocolGuid,
-
+                          (VOID **) &SimpleTextInput,
-      FreePool (OpenInfoBuffer);
+                          This->DriverBindingHandle,
-      if (EFI_ERROR (Status)) {
+                          Controller,
-          goto Error;
+                          EFI_OPEN_PROTOCOL_GET_PROTOCOL
-      }
+                          );
-    }
+          if (!EFI_ERROR (Status)) {
-
+            TerminalDevice = TERMINAL_CON_IN_DEV_FROM_THIS (SimpleTextInput);
+            TerminalType = TerminalTypeFromGuid (&((VENDOR_DEVICE_PATH *) RemainingDevicePath)->Guid);
+            ASSERT (TerminalType < ARRAY_SIZE (mTerminalType));
+            if (TerminalDevice->TerminalType != TerminalType) {
+              Status = InitializeControllerNameTable (TerminalType, &ControllerNameTable);
+              if (!EFI_ERROR (Status)) {
+                StopTerminalStateMachine (TerminalDevice);
                 //
-    // If RemainingDevicePath is NULL, use default terminal type
+                // Update the device path
                 //
-    if (RemainingDevicePath == NULL) {
+                Vendor = TerminalDevice->DevicePath;
-      TerminalType = PcdGet8 (PcdDefaultTerminalType);
+                Status = gBS->LocateDevicePath (&gEfiSerialIoProtocolGuid, &Vendor, &SerialIoHandle);
-    } else if (!IsDevicePathEnd (RemainingDevicePath)) {
+                ASSERT_EFI_ERROR (Status);
-      //
+                CopyGuid (&((VENDOR_DEVICE_PATH *) Vendor)->Guid, mTerminalType[TerminalType]);
-      // If RemainingDevicePath isn't the End of Device Path Node,
+                Status = gBS->ReinstallProtocolInterface (
-      // Use the RemainingDevicePath to determine the terminal type
+                                TerminalDevice->Handle,
-      //
+                                &gEfiDevicePathProtocolGuid,
-      Node = (VENDOR_DEVICE_PATH *)RemainingDevicePath;
+                                TerminalDevice->DevicePath,
-      TerminalType = TerminalTypeFromGuid (&Node->Guid);
+                                TerminalDevice->DevicePath
+                                );
+                if (!EFI_ERROR (Status)) {
+                  TerminalDevice->TerminalType = TerminalType;
+                  StartTerminalStateMachine (TerminalDevice);
+                  FreeUnicodeStringTable (TerminalDevice->ControllerNameTable);
+                  TerminalDevice->ControllerNameTable = ControllerNameTable;
                 } else {
                   //
-      // If RemainingDevicePath is the End of Device Path Node,
+                  // Restore the device path on failure
-      // skip enumerate any device and return EFI_SUCESSS
                   //
-      return EFI_SUCCESS;
+                  CopyGuid (&((VENDOR_DEVICE_PATH *) Vendor)->Guid, mTerminalType[TerminalDevice->TerminalType]);
+                  FreeUnicodeStringTable (ControllerNameTable);
+                }
+              }
+            }
+          }
+          break;
+        }
+      }
+      FreePool (OpenInfoBuffer);
+    }
+    return Status;
   }
-
-    ASSERT (TerminalType < ARRAY_SIZE (mTerminalType));
 
   //
   // Initialize the Terminal Dev
@@ -805,12 +605,44 @@ TerminalDriverBindingStart (
   TerminalDevice = AllocateCopyPool (sizeof (TERMINAL_DEV), &mTerminalDevTemplate);
   if (TerminalDevice == NULL) {
     Status = EFI_OUT_OF_RESOURCES;
-      goto Error;
+    goto CloseProtocols;
   }
 
-    TerminalDevice->TerminalType  = TerminalType;
+  if (RemainingDevicePath == NULL) {
+    //
+    // If RemainingDevicePath is NULL, use default terminal type
+    //
+    TerminalDevice->TerminalType = PcdGet8 (PcdDefaultTerminalType);
+  } else {
+    //
+    // End of Device Path Node is handled in above.
+    //
+    ASSERT (!IsDevicePathEnd (RemainingDevicePath));
+    //
+    // If RemainingDevicePath isn't the End of Device Path Node,
+    // Use the RemainingDevicePath to determine the terminal type
+    //
+    TerminalDevice->TerminalType = TerminalTypeFromGuid (&((VENDOR_DEVICE_PATH *) RemainingDevicePath)->Guid);
+  }
+  ASSERT (TerminalDevice->TerminalType < ARRAY_SIZE (mTerminalType));
   TerminalDevice->SerialIo = SerialIo;
 
+  //
+  // Build the component name for the child device
+  //
+  Status = InitializeControllerNameTable (TerminalDevice->TerminalType, &TerminalDevice->ControllerNameTable);
+  if (EFI_ERROR (Status)) {
+    goto FreeResources;
+  }
+
+  //
+  // Build the device path for the child device
+  //
+  Status = SetTerminalDevicePath (TerminalDevice->TerminalType, ParentDevicePath, &TerminalDevice->DevicePath);
+  if (EFI_ERROR (Status)) {
+    goto FreeResources;
+  }
+
   InitializeListHead (&TerminalDevice->NotifyList);
   Status = gBS->CreateEvent (
                   EVT_NOTIFY_WAIT,
@@ -819,9 +651,7 @@ TerminalDriverBindingStart (
                   TerminalDevice,
                   &TerminalDevice->SimpleInputEx.WaitForKeyEx
                   );
-    if (EFI_ERROR (Status)) {
+  ASSERT_EFI_ERROR (Status);
-      goto Error;
-    }
 
   Status = gBS->CreateEvent (
                   EVT_NOTIFY_WAIT,
@@ -830,33 +660,39 @@ TerminalDriverBindingStart (
                   TerminalDevice,
                   &TerminalDevice->SimpleInput.WaitForKey
                   );
-    if (EFI_ERROR (Status)) {
+  ASSERT_EFI_ERROR (Status);
-      goto Error;
+  Status = gBS->CreateEvent (
-    }
+                  EVT_NOTIFY_SIGNAL,
+                  TPL_CALLBACK,
+                  KeyNotifyProcessHandler,
+                  TerminalDevice,
+                  &TerminalDevice->KeyNotifyProcessEvent
+                  );
+  ASSERT_EFI_ERROR (Status);
+
   //
   // Allocates and initializes the FIFO buffer to be zero, used for accommodating
   // the pre-read pending characters.
   //
   TerminalDevice->RawFiFo = AllocateZeroPool (sizeof (RAW_DATA_FIFO));
   if (TerminalDevice->RawFiFo == NULL) {
-      goto Error;
+    goto FreeResources;
   }
   TerminalDevice->UnicodeFiFo = AllocateZeroPool (sizeof (UNICODE_FIFO));
   if (TerminalDevice->UnicodeFiFo == NULL) {
-      goto Error;
+    goto FreeResources;
   }
   TerminalDevice->EfiKeyFiFo = AllocateZeroPool (sizeof (EFI_KEY_FIFO));
   if (TerminalDevice->EfiKeyFiFo == NULL) {
-      goto Error;
+    goto FreeResources;
   }
   TerminalDevice->EfiKeyFiFoForNotify = AllocateZeroPool (sizeof (EFI_KEY_FIFO));
   if (TerminalDevice->EfiKeyFiFoForNotify == NULL) {
-      goto Error;
+    goto FreeResources;
   }
 
   //
-    // Set the timeout value of serial buffer for
+  // Set the timeout value of serial buffer for keystroke response performance issue
-    // keystroke response performance issue
   //
   Mode = TerminalDevice->SerialIo->Mode;
 
@@ -886,95 +722,49 @@ TerminalDriverBindingStart (
   } else {
     TerminalDevice->SerialInTimeOut = SerialInTimeOut;
   }
-    //
-    // Set Simple Text Output Protocol from template.
-    //
-    SimpleTextOutput = CopyMem (
-                         &TerminalDevice->SimpleTextOutput,
-                         &mTerminalDevTemplate.SimpleTextOutput,
-                         sizeof (mTerminalDevTemplate.SimpleTextOutput)
-                         );
-    SimpleTextOutput->Mode = &TerminalDevice->SimpleTextOutputMode;
 
+  SimpleTextOutput = &TerminalDevice->SimpleTextOutput;
+  SimpleTextInput = &TerminalDevice->SimpleInput;
+
+  //
+  // Initialize SimpleTextOut instance
+  //
+  SimpleTextOutput->Mode = &TerminalDevice->SimpleTextOutputMode;
   TerminalDevice->TerminalConsoleModeData = InitializeTerminalConsoleTextMode (
     &SimpleTextOutput->Mode->MaxMode
   );
   if (TerminalDevice->TerminalConsoleModeData == NULL) {
-      goto ReportError;
+    goto FreeResources;
   }
-
   //
   // For terminal devices, cursor is always visible
   //
-    TerminalDevice->SimpleTextOutputMode.CursorVisible = TRUE;
+  SimpleTextOutput->Mode->CursorVisible = TRUE;
-    Status = TerminalConOutSetAttribute (
+  Status = SimpleTextOutput->SetAttribute (SimpleTextOutput, EFI_TEXT_ATTR (EFI_LIGHTGRAY, EFI_BLACK));
-               SimpleTextOutput,
+  if (!EFI_ERROR (Status)) {
-               EFI_TEXT_ATTR (EFI_LIGHTGRAY, EFI_BLACK)
+    Status = SimpleTextOutput->Reset (SimpleTextOutput, FALSE);
-               );
+  }
   if (EFI_ERROR (Status)) {
     goto ReportError;
   }
 
   //
-    // Build the component name for the child device
+  // Initialize SimpleTextInput instance
   //
-    Status = InitializeControllerNameTable (TerminalDevice->TerminalType, &TerminalDevice->ControllerNameTable);
+  Status = SimpleTextInput->Reset (SimpleTextInput, FALSE);
-    if (EFI_ERROR (Status)) {
-      goto Error;
-    }
-
-    //
-    // Build the device path for the child device
-    //
-    Status = SetTerminalDevicePath (
-              TerminalDevice->TerminalType,
-              ParentDevicePath,
-              &TerminalDevice->DevicePath
-              );
-    if (EFI_ERROR (Status)) {
-      goto Error;
-    }
-
-    Status = TerminalConOutReset (SimpleTextOutput, FALSE);
   if (EFI_ERROR (Status)) {
     goto ReportError;
   }
 
-    Status = TerminalConOutSetMode (SimpleTextOutput, 0);
+  Status = gBS->InstallMultipleProtocolInterfaces (
-    if (EFI_ERROR (Status)) {
-      goto ReportError;
-    }
-
-    Status = TerminalConOutEnableCursor (SimpleTextOutput, TRUE);
-    if (EFI_ERROR (Status)) {
-      goto ReportError;
-    }
-
-    StartTerminalStateMachine (TerminalDevice);
-
-    Status = gBS->CreateEvent (
-                    EVT_NOTIFY_SIGNAL,
-                    TPL_CALLBACK,
-                    KeyNotifyProcessHandler,
-                    TerminalDevice,
-                    &TerminalDevice->KeyNotifyProcessEvent
-                    );
-    ASSERT_EFI_ERROR (Status);
-
-    Status = gBS->InstallProtocolInterface (
                   &TerminalDevice->Handle,
-                    &gEfiDevicePathProtocolGuid,
+                  &gEfiSimpleTextInProtocolGuid,      &TerminalDevice->SimpleInput,
-                    EFI_NATIVE_INTERFACE,
+                  &gEfiSimpleTextInputExProtocolGuid, &TerminalDevice->SimpleInputEx,
-                    TerminalDevice->DevicePath
+                  &gEfiSimpleTextOutProtocolGuid,     &TerminalDevice->SimpleTextOutput,
+                  &gEfiDevicePathProtocolGuid,        TerminalDevice->DevicePath,
+                  NULL
                   );
-    if (EFI_ERROR (Status)) {
+  if (!EFI_ERROR (Status)) {
-      goto Error;
-    }
-
-    //
-    // Register the Parent-Child relationship via
-    // EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.
-    //
     Status = gBS->OpenProtocol (
                     Controller,
                     &gEfiSerialIoProtocolGuid,
@@ -983,196 +773,30 @@ TerminalDriverBindingStart (
                     TerminalDevice->Handle,
                     EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
                     );
-    if (EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
-      goto Error;
+    StartTerminalStateMachine (TerminalDevice);
+    return Status;
   }
-  }
-
-  //
-  // Find the child handle, and get its TerminalDevice private data
-  //
-  Status = gBS->OpenProtocolInformation (
-                  Controller,
-                  &gEfiSerialIoProtocolGuid,
-                  &OpenInfoBuffer,
-                  &EntryCount
-                  );
-  if (!EFI_ERROR (Status)) {
-    Status = EFI_NOT_FOUND;
-    ASSERT (OpenInfoBuffer != NULL);
-    for (Index = 0; Index < EntryCount; Index++) {
-      if ((OpenInfoBuffer[Index].Attributes & EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER) != 0) {
-        //
-        // Find the child terminal handle.
-        // Test whether the SimpleTxtIn and SimpleTxtOut have been published
-        //
-        Status = gBS->OpenProtocol (
-                        OpenInfoBuffer[Index].ControllerHandle,
-                        &gEfiSimpleTextInProtocolGuid,
-                        (VOID **) &SimpleTextInput,
-                        This->DriverBindingHandle,
-                        OpenInfoBuffer[Index].ControllerHandle,
-                        EFI_OPEN_PROTOCOL_GET_PROTOCOL
-                        );
-        if (!EFI_ERROR (Status)) {
-          SimTxtInInstalled = TRUE;
-          TerminalDevice = TERMINAL_CON_IN_DEV_FROM_THIS (SimpleTextInput);
-        }
-
-        Status = gBS->OpenProtocol (
-                        OpenInfoBuffer[Index].ControllerHandle,
-                        &gEfiSimpleTextOutProtocolGuid,
-                        (VOID **) &SimpleTextOutput,
-                        This->DriverBindingHandle,
-                        OpenInfoBuffer[Index].ControllerHandle,
-                        EFI_OPEN_PROTOCOL_GET_PROTOCOL
-                        );
-        if (!EFI_ERROR (Status)) {
-          SimTxtOutInstalled = TRUE;
-          TerminalDevice = TERMINAL_CON_OUT_DEV_FROM_THIS (SimpleTextOutput);
-        }
-        Status = EFI_SUCCESS;
-        break;
-      }
-    }
-
-    FreePool (OpenInfoBuffer);
-    if (EFI_ERROR (Status)) {
-      goto ReportError;
-    }
-  } else {
-    goto ReportError;
-  }
-
-  ASSERT (TerminalDevice != NULL);
-  //
-  // Only do the reset if the device path is in the Conout variable
-  //
-  if (ConInSelected && !SimTxtInInstalled) {
-    Status = TerminalDevice->SimpleInput.Reset (
-                                          &TerminalDevice->SimpleInput,
-                                          FALSE
-                                          );
-    if (EFI_ERROR (Status)) {
-      //
-      // Need to report Error Code first
-      //
-      goto ReportError;
-    }
-  }
-
-  //
-  // Only output the configure string to remote terminal if the device path
-  // is in the Conout variable
-  //
-  if (ConOutSelected && !SimTxtOutInstalled) {
-    Status = TerminalDevice->SimpleTextOutput.SetAttribute (
-                                                        &TerminalDevice->SimpleTextOutput,
-                                                        EFI_TEXT_ATTR (EFI_LIGHTGRAY, EFI_BLACK)
-                                                        );
-    if (EFI_ERROR (Status)) {
-      goto ReportError;
-    }
-
-    Status = TerminalDevice->SimpleTextOutput.Reset (
-                                                &TerminalDevice->SimpleTextOutput,
-                                                FALSE
-                                                );
-    if (EFI_ERROR (Status)) {
-      goto ReportError;
-    }
-
-    Status = TerminalDevice->SimpleTextOutput.SetMode (
-                                                &TerminalDevice->SimpleTextOutput,
-                                                0
-                                                );
-    if (EFI_ERROR (Status)) {
-      goto ReportError;
-    }
-
-    Status = TerminalDevice->SimpleTextOutput.EnableCursor (
-                                                &TerminalDevice->SimpleTextOutput,
-                                                TRUE
-                                                );
-    if (EFI_ERROR (Status)) {
-      goto ReportError;
-    }
-  }
-
-  //
-  // Simple In/Out Protocol will not be installed onto the handle if the
-  // device path to the handle is not present in the ConIn/ConOut
-  // environment variable. But If RemainingDevicePath is NULL, then always
-  // produce both Simple In and Simple Text Output Protocols. This is required
-  // for the connect all sequences to make sure all possible consoles are
-  // produced no matter what the current values of ConIn, ConOut, or StdErr are.
-  //
-  if (!SimTxtInInstalled && (ConInSelected || NullRemaining)) {
-    Status = gBS->InstallMultipleProtocolInterfaces (
-                    &TerminalDevice->Handle,
-                    &gEfiSimpleTextInProtocolGuid,
-                    &TerminalDevice->SimpleInput,
-                    &gEfiSimpleTextInputExProtocolGuid,
-                    &TerminalDevice->SimpleInputEx,
-                    NULL
-                    );
-    if (EFI_ERROR (Status)) {
-      goto Error;
-    }
-  }
-
-  if (!SimTxtOutInstalled && (ConOutSelected || NullRemaining)) {
-    Status = gBS->InstallProtocolInterface (
-                    &TerminalDevice->Handle,
-                    &gEfiSimpleTextOutProtocolGuid,
-                    EFI_NATIVE_INTERFACE,
-                    &TerminalDevice->SimpleTextOutput
-                    );
-    if (EFI_ERROR (Status)) {
-      goto Error;
-    }
-  }
-
-  return EFI_SUCCESS;
 
 ReportError:
-  //
-  // Report error code before exiting
-  //
-  DevicePath = ParentDevicePath;
   REPORT_STATUS_CODE_WITH_DEVICE_PATH (
     EFI_ERROR_CODE | EFI_ERROR_MINOR,
     (EFI_PERIPHERAL_REMOTE_CONSOLE | EFI_P_EC_CONTROLLER_ERROR),
-    DevicePath
+    ParentDevicePath
     );
 
-Error:
+FreeResources:
-  //
+  ASSERT (TerminalDevice != NULL);
-  // Use the Stop() function to free all resources allocated in Start()
-  //
-  if (TerminalDevice != NULL) {
-
-    if (TerminalDevice->Handle != NULL) {
-      This->Stop (This, Controller, 1, &TerminalDevice->Handle);
-    } else {
-
-      if (TerminalDevice->TwoSecondTimeOut != NULL) {
-        gBS->CloseEvent (TerminalDevice->TwoSecondTimeOut);
-      }
-
-      if (TerminalDevice->TimerEvent != NULL) {
-        gBS->CloseEvent (TerminalDevice->TimerEvent);
-      }
 
   if (TerminalDevice->SimpleInput.WaitForKey != NULL) {
     gBS->CloseEvent (TerminalDevice->SimpleInput.WaitForKey);
   }
-
   if (TerminalDevice->SimpleInputEx.WaitForKeyEx != NULL) {
     gBS->CloseEvent (TerminalDevice->SimpleInputEx.WaitForKeyEx);
   }
-
+  if (TerminalDevice->KeyNotifyProcessEvent != NULL) {
-      TerminalFreeNotifyList (&TerminalDevice->NotifyList);
+    gBS->CloseEvent (TerminalDevice->KeyNotifyProcessEvent);
+  }
 
   if (TerminalDevice->RawFiFo != NULL) {
     FreePool (TerminalDevice->RawFiFo);
@@ -1200,11 +824,32 @@ Error:
   }
 
   FreePool (TerminalDevice);
-    }
-  }
 
-  This->Stop (This, Controller, 0, NULL);
+CloseProtocols:
 
+  //
+  // Remove Parent Device Path from
+  // the Console Device Environment Variables
+  //
+  TerminalRemoveConsoleDevVariable (EFI_CON_IN_DEV_VARIABLE_NAME, ParentDevicePath);
+  TerminalRemoveConsoleDevVariable (EFI_CON_OUT_DEV_VARIABLE_NAME, ParentDevicePath);
+  TerminalRemoveConsoleDevVariable (EFI_ERR_OUT_DEV_VARIABLE_NAME, ParentDevicePath);
+
+  Status = gBS->CloseProtocol (
+                  Controller,
+                  &gEfiSerialIoProtocolGuid,
+                  This->DriverBindingHandle,
+                  Controller
+                  );
+  ASSERT_EFI_ERROR (Status);
+
+  Status = gBS->CloseProtocol (
+                  Controller,
+                  &gEfiDevicePathProtocolGuid,
+                  This->DriverBindingHandle,
+                  Controller
+                  );
+  ASSERT_EFI_ERROR (Status);
   return Status;
 }
 
@@ -1239,16 +884,6 @@ TerminalDriverBindingStop (
   TERMINAL_DEV                     *TerminalDevice;
   EFI_DEVICE_PATH_PROTOCOL         *ParentDevicePath;
   EFI_SERIAL_IO_PROTOCOL           *SerialIo;
-  EFI_DEVICE_PATH_PROTOCOL         *DevicePath;
-
-  Status = gBS->HandleProtocol (
-                  Controller,
-                  &gEfiDevicePathProtocolGuid,
-                  (VOID **) &DevicePath
-                  );
-  if (EFI_ERROR (Status)) {
-    return Status;
-  }
 
   //
   // Complete all outstanding transactions to Controller.
@@ -1260,38 +895,21 @@ TerminalDriverBindingStop (
     //
     Status = gBS->OpenProtocol (
                     Controller,
-                    &gEfiCallerIdGuid,
+                    &gEfiDevicePathProtocolGuid,
                     (VOID **) &ParentDevicePath,
                     This->DriverBindingHandle,
                     Controller,
                     EFI_OPEN_PROTOCOL_GET_PROTOCOL
                     );
-    if (!EFI_ERROR (Status)) {
+    ASSERT_EFI_ERROR (Status);
+
     //
     // Remove Parent Device Path from
     // the Console Device Environment Variables
     //
-      TerminalRemoveConsoleDevVariable (L"ConInDev", ParentDevicePath);
+    TerminalRemoveConsoleDevVariable (EFI_CON_IN_DEV_VARIABLE_NAME, ParentDevicePath);
-      TerminalRemoveConsoleDevVariable (L"ConOutDev", ParentDevicePath);
+    TerminalRemoveConsoleDevVariable (EFI_CON_OUT_DEV_VARIABLE_NAME, ParentDevicePath);
-      TerminalRemoveConsoleDevVariable (L"ErrOutDev", ParentDevicePath);
+    TerminalRemoveConsoleDevVariable (EFI_ERR_OUT_DEV_VARIABLE_NAME, ParentDevicePath);
-
-      //
-      // Uninstall the Terminal Driver's GUID Tag from the Serial controller
-      //
-      Status = gBS->UninstallMultipleProtocolInterfaces (
-                      Controller,
-                      &gEfiCallerIdGuid,
-                      ParentDevicePath,
-                      NULL
-                      );
-
-      //
-      // Free the ParentDevicePath that was duplicated in Start()
-      //
-      if (!EFI_ERROR (Status)) {
-        FreePool (ParentDevicePath);
-      }
-    }
 
     gBS->CloseProtocol (
           Controller,