Nt32Pkg/WinNtSerialIoDxe/WinNtSerialIo.c

   1 /**@file
   2
   3 Copyright (c) 2006 - 2010, Intel Corporation
   4 All rights reserved. This program and the accompanying materials
   5 are licensed and made available under the terms and conditions of the BSD License
   6 which accompanies this distribution.  The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12 Module Name:
  13
  14   WinNtSerialIo.c
  15
  16 Abstract:
  17
  18   Our DriverBinding member functions operate on the handles
  19   created by the NT Bus driver.
  20
  21   Handle(1) - WinNtIo - DevicePath(1)
  22
  23   If a serial port is added to the system this driver creates a new handle.
  24   The new handle is required, since the serial device must add an UART device
  25   pathnode.
  26
  27   Handle(2) - SerialIo - DevicePath(1)\UART
  28
  29   The driver then adds a gEfiWinNtSerialPortGuid as a protocol to Handle(1).
  30   The instance data for this protocol is the private data used to create
  31   Handle(2).
  32
  33   Handle(1) - WinNtIo - DevicePath(1) - WinNtSerialPort
  34
  35   If the driver is unloaded Handle(2) is removed from the system and
  36   gEfiWinNtSerialPortGuid is removed from Handle(1).
  37
  38   Note: Handle(1) is any handle created by the Win NT Bus driver that is passed
  39   into the DriverBinding member functions of this driver. This driver requires
  40   a Handle(1) to contain a WinNtIo protocol, a DevicePath protocol, and
  41   the TypeGuid in the WinNtIo must be gEfiWinNtSerialPortGuid.
  42
  43   If Handle(1) contains a gEfiWinNtSerialPortGuid protocol then the driver is
  44   loaded on the device.
  45
  46 **/
  47
  48 #include "WinNtSerialIo.h"
  49
  50 EFI_DRIVER_BINDING_PROTOCOL gWinNtSerialIoDriverBinding = {
  51   WinNtSerialIoDriverBindingSupported,
  52   WinNtSerialIoDriverBindingStart,
  53   WinNtSerialIoDriverBindingStop,
  54   0xa,
  55   NULL,
  56   NULL
  57 };
  58
  59 //
  60 // List of supported baud rate
  61 //
  62 UINT64 mBaudRateCurrentSupport[] = {50, 75, 110, 134, 150, 300, 600, 1200, 1800, 2000, 2400, 3600, 4800, 7200, 9600, 19200, 38400, 57600, 115200, SERIAL_PORT_MAX_BAUD_RATE + 1};
  63
  64 /**
  65   The user Entry Point for module WinNtSerialIo. The user code starts with this function.
  66
  67   @param[in] ImageHandle    The firmware allocated handle for the EFI image.
  68   @param[in] SystemTable    A pointer to the EFI System Table.
  69
  70   @retval EFI_SUCCESS       The entry point is executed successfully.
  71   @retval other             Some error occurs when executing this entry point.
  72
  73 **/
  74 EFI_STATUS
  75 EFIAPI
  76 InitializeWinNtSerialIo(
  77   IN EFI_HANDLE           ImageHandle,
  78   IN EFI_SYSTEM_TABLE     *SystemTable
  79   )
  80 {
  81   EFI_STATUS              Status;
  82
  83   //
  84   // Install driver model protocol(s).
  85   //
  86   Status = EfiLibInstallDriverBindingComponentName2 (
  87              ImageHandle,
  88              SystemTable,
  89              &gWinNtSerialIoDriverBinding,
  90              ImageHandle,
  91              &gWinNtSerialIoComponentName,
  92              &gWinNtSerialIoComponentName2
  93              );
  94   ASSERT_EFI_ERROR (Status);
  95
  96
  97   return Status;
  98 }
  99
 100 EFI_STATUS
 101 EFIAPI
 102 WinNtSerialIoDriverBindingSupported (
 103   IN  EFI_DRIVER_BINDING_PROTOCOL   *This,
 104   IN  EFI_HANDLE                    Handle,
 105   IN  EFI_DEVICE_PATH_PROTOCOL      *RemainingDevicePath
 106   )
 107 /*++
 108
 109 Routine Description:
 110
 111 Arguments:
 112
 113 Returns:
 114
 115   None
 116
 117 --*/
 118 // TODO:    This - add argument and description to function comment
 119 // TODO:    Handle - add argument and description to function comment
 120 // TODO:    RemainingDevicePath - add argument and description to function comment
 121 // TODO:    EFI_SUCCESS - add return value to function comment
 122 // TODO:    EFI_SUCCESS - add return value to function comment
 123 {
 124   EFI_STATUS                Status;
 125   EFI_DEVICE_PATH_PROTOCOL  *ParentDevicePath;
 126   EFI_WIN_NT_IO_PROTOCOL    *WinNtIo;
 127   UART_DEVICE_PATH          *UartNode;
 128
 129   //
 130   // Check RemainingDevicePath validation
 131   //
 132   if (RemainingDevicePath != NULL) {
 133     //
 134     // Check if RemainingDevicePath is the End of Device Path Node,
 135     // if yes, go on checking other conditions
 136     //
 137     if (!IsDevicePathEnd (RemainingDevicePath)) {
 138       //
 139       // If RemainingDevicePath isn't the End of Device Path Node,
 140       // check its validation
 141       //
 142       Status = EFI_UNSUPPORTED;
 143
 144       UartNode  = (UART_DEVICE_PATH *) RemainingDevicePath;
 145       if (UartNode->Header.Type != MESSAGING_DEVICE_PATH ||
 146           UartNode->Header.SubType != MSG_UART_DP ||
 147           DevicePathNodeLength((EFI_DEVICE_PATH_PROTOCOL *)UartNode) != sizeof(UART_DEVICE_PATH)) {
 148         goto Error;
 149       }
 150       if ( UartNode->BaudRate > SERIAL_PORT_MAX_BAUD_RATE) {
 151         goto Error;
 152       }
 153       if (UartNode->Parity < NoParity || UartNode->Parity > SpaceParity) {
 154         goto Error;
 155       }
 156       if (UartNode->DataBits < 5 || UartNode->DataBits > 8) {
 157         goto Error;
 158       }
 159       if (UartNode->StopBits < OneStopBit || UartNode->StopBits > TwoStopBits) {
 160         goto Error;
 161       }
 162       if ((UartNode->DataBits == 5) && (UartNode->StopBits == TwoStopBits)) {
 163         goto Error;
 164       }
 165       if ((UartNode->DataBits >= 6) && (UartNode->DataBits <= 8) && (UartNode->StopBits == OneFiveStopBits)) {
 166         goto Error;
 167       }
 168     }
 169   }
 170
 171   //
 172   // Open the IO Abstraction(s) needed to perform the supported test
 173   //
 174   Status = gBS->OpenProtocol (
 175                   Handle,
 176                   &gEfiWinNtIoProtocolGuid,
 177                   (VOID **) &WinNtIo,
 178                   This->DriverBindingHandle,
 179                   Handle,
 180                   EFI_OPEN_PROTOCOL_BY_DRIVER
 181                   );
 182   if (Status == EFI_ALREADY_STARTED) {
 183     return EFI_SUCCESS;
 184   }
 185
 186   if (EFI_ERROR (Status)) {
 187     return Status;
 188   }
 189
 190   //
 191   // Close the I/O Abstraction(s) used to perform the supported test
 192   //
 193   gBS->CloseProtocol (
 194         Handle,
 195         &gEfiWinNtIoProtocolGuid,
 196         This->DriverBindingHandle,
 197         Handle
 198         );
 199
 200   //
 201   // Open the EFI Device Path protocol needed to perform the supported test
 202   //
 203   Status = gBS->OpenProtocol (
 204                   Handle,
 205                   &gEfiDevicePathProtocolGuid,
 206                   (VOID **) &ParentDevicePath,
 207                   This->DriverBindingHandle,
 208                   Handle,
 209                   EFI_OPEN_PROTOCOL_BY_DRIVER
 210                   );
 211   if (Status == EFI_ALREADY_STARTED) {
 212     return EFI_SUCCESS;
 213   }
 214
 215   if (EFI_ERROR (Status)) {
 216     return Status;
 217   }
 218
 219   //
 220   // Close protocol, don't use device path protocol in the Support() function
 221   //
 222   gBS->CloseProtocol (
 223         Handle,
 224         &gEfiDevicePathProtocolGuid,
 225         This->DriverBindingHandle,
 226         Handle
 227         );
 228
 229   //
 230   // Make sure that the WinNt Thunk Protocol is valid
 231   //
 232   if (WinNtIo->WinNtThunk->Signature != EFI_WIN_NT_THUNK_PROTOCOL_SIGNATURE) {
 233     Status = EFI_UNSUPPORTED;
 234     goto Error;
 235   }
 236
 237   //
 238   // Check the GUID to see if this is a handle type the driver supports
 239   //
 240   if (!CompareGuid (WinNtIo->TypeGuid, &gEfiWinNtSerialPortGuid)) {
 241     Status = EFI_UNSUPPORTED;
 242     goto Error;
 243   }
 244
 245   return EFI_SUCCESS;
 246
 247 Error:
 248   return Status;
 249 }
 250
 251 EFI_STATUS
 252 EFIAPI
 253 WinNtSerialIoDriverBindingStart (
 254   IN  EFI_DRIVER_BINDING_PROTOCOL   *This,
 255   IN  EFI_HANDLE                    Handle,
 256   IN  EFI_DEVICE_PATH_PROTOCOL      *RemainingDevicePath
 257   )
 258 /*++
 259
 260 Routine Description:
 261
 262 Arguments:
 263
 264 Returns:
 265
 266   None
 267
 268 --*/
 269 // TODO:    This - add argument and description to function comment
 270 // TODO:    Handle - add argument and description to function comment
 271 // TODO:    RemainingDevicePath - add argument and description to function comment
 272 // TODO:    EFI_SUCCESS - add return value to function comment
 273 // TODO:    EFI_SUCCESS - add return value to function comment
 274 {
 275   EFI_STATUS                          Status;
 276   EFI_WIN_NT_IO_PROTOCOL              *WinNtIo;
 277   WIN_NT_SERIAL_IO_PRIVATE_DATA       *Private;
 278   HANDLE                              NtHandle;
 279   UART_DEVICE_PATH                    Node;
 280   EFI_DEVICE_PATH_PROTOCOL            *ParentDevicePath;
 281   EFI_OPEN_PROTOCOL_INFORMATION_ENTRY *OpenInfoBuffer;
 282   UINTN                               EntryCount;
 283   UINTN                               Index;
 284   EFI_SERIAL_IO_PROTOCOL              *SerialIo;
 285   UART_DEVICE_PATH                    *UartNode;
 286
 287   Private   = NULL;
 288   NtHandle  = INVALID_HANDLE_VALUE;
 289
 290   //
 291   // Grab the protocols we need
 292   //
 293   Status = gBS->OpenProtocol (
 294                   Handle,
 295                   &gEfiDevicePathProtocolGuid,
 296                   (VOID **) &ParentDevicePath,
 297                   This->DriverBindingHandle,
 298                   Handle,
 299                   EFI_OPEN_PROTOCOL_BY_DRIVER
 300                   );
 301   if (EFI_ERROR (Status) && Status != EFI_ALREADY_STARTED) {
 302     return Status;
 303   }
 304
 305   //
 306   // Grab the IO abstraction we need to get any work done
 307   //
 308   Status = gBS->OpenProtocol (
 309                   Handle,
 310                   &gEfiWinNtIoProtocolGuid,
 311                   (VOID **) &WinNtIo,
 312                   This->DriverBindingHandle,
 313                   Handle,
 314                   EFI_OPEN_PROTOCOL_BY_DRIVER
 315                   );
 316   if (EFI_ERROR (Status) && Status != EFI_ALREADY_STARTED) {
 317     gBS->CloseProtocol (
 318           Handle,
 319           &gEfiDevicePathProtocolGuid,
 320           This->DriverBindingHandle,
 321           Handle
 322           );
 323     return Status;
 324   }
 325
 326   if (Status == EFI_ALREADY_STARTED) {
 327
 328     if (RemainingDevicePath == NULL || IsDevicePathEnd (RemainingDevicePath)) {
 329       //
 330       // If RemainingDevicePath is NULL or is the End of Device Path Node
 331       //
 332       return EFI_SUCCESS;
 333     }
 334
 335     //
 336     // Make sure a child handle does not already exist.  This driver can only
 337     // produce one child per serial port.
 338     //
 339     Status = gBS->OpenProtocolInformation (
 340                     Handle,
 341                     &gEfiWinNtIoProtocolGuid,
 342                     &OpenInfoBuffer,
 343                     &EntryCount
 344                     );
 345     if (EFI_ERROR (Status)) {
 346       return Status;
 347     }
 348
 349     Status = EFI_ALREADY_STARTED;
 350     for (Index = 0; Index < EntryCount; Index++) {
 351       if (OpenInfoBuffer[Index].Attributes & EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER) {
 352         Status = gBS->OpenProtocol (
 353                         OpenInfoBuffer[Index].ControllerHandle,
 354                         &gEfiSerialIoProtocolGuid,
 355                         (VOID **) &SerialIo,
 356                         This->DriverBindingHandle,
 357                         Handle,
 358                         EFI_OPEN_PROTOCOL_GET_PROTOCOL
 359                         );
 360         if (!EFI_ERROR (Status)) {
 361           UartNode = (UART_DEVICE_PATH *) RemainingDevicePath;
 362           Status = SerialIo->SetAttributes (
 363                               SerialIo,
 364                               UartNode->BaudRate,
 365                               SerialIo->Mode->ReceiveFifoDepth,
 366                               SerialIo->Mode->Timeout,
 367                               (EFI_PARITY_TYPE)UartNode->Parity,
 368                               UartNode->DataBits,
 369                               (EFI_STOP_BITS_TYPE)UartNode->StopBits
 370                               );
 371         }
 372         break;
 373       }
 374     }
 375
 376     FreePool (OpenInfoBuffer);
 377     return Status;
 378   }
 379
 380   if (RemainingDevicePath == NULL) {
 381     //
 382     // Build the device path by appending the UART node to the ParentDevicePath
 383     // from the WinNtIo handle. The Uart setings are zero here, since
 384     // SetAttribute() will update them to match the default setings.
 385     //
 386     ZeroMem (&Node, sizeof (UART_DEVICE_PATH));
 387     Node.Header.Type     = MESSAGING_DEVICE_PATH;
 388     Node.Header.SubType  = MSG_UART_DP;
 389     SetDevicePathNodeLength ((EFI_DEVICE_PATH_PROTOCOL *) &Node, sizeof (UART_DEVICE_PATH));
 390
 391   } else if (!IsDevicePathEnd (RemainingDevicePath)) {
 392     //
 393     // If RemainingDevicePath isn't the End of Device Path Node,
 394     // only scan the specified device by RemainingDevicePath
 395     //
 396     //
 397     // Match the configuration of the RemainingDevicePath. IsHandleSupported()
 398     // already checked to make sure the RemainingDevicePath contains settings
 399     // that we can support.
 400     //
 401     CopyMem (&Node, RemainingDevicePath, sizeof (UART_DEVICE_PATH));
 402
 403   } else {
 404     //
 405     // If RemainingDevicePath is the End of Device Path Node,
 406     // skip enumerate any device and return EFI_SUCESSS
 407     //
 408     return EFI_SUCCESS;
 409   }
 410
 411   //
 412   // Check to see if we can access the hardware device. If it's Open in NT we
 413   // will not get access.
 414   //
 415   NtHandle = WinNtIo->WinNtThunk->CreateFile (
 416                                     WinNtIo->EnvString,
 417                                     GENERIC_READ | GENERIC_WRITE,
 418                                     0,
 419                                     NULL,
 420                                     OPEN_EXISTING,
 421                                     0,
 422                                     NULL
 423                                     );
 424   if (NtHandle == INVALID_HANDLE_VALUE) {
 425     Status = EFI_DEVICE_ERROR;
 426     goto Error;
 427   }
 428
 429   //
 430   // Construct Private data
 431   //
 432   Private = AllocatePool (sizeof (WIN_NT_SERIAL_IO_PRIVATE_DATA));
 433   if (Private == NULL) {
 434     goto Error;
 435   }
 436
 437   //
 438   // This signature must be valid before any member function is called
 439   //
 440   Private->Signature              = WIN_NT_SERIAL_IO_PRIVATE_DATA_SIGNATURE;
 441   Private->NtHandle               = NtHandle;
 442   Private->ControllerHandle       = Handle;
 443   Private->Handle                 = NULL;
 444   Private->WinNtThunk             = WinNtIo->WinNtThunk;
 445   Private->ParentDevicePath       = ParentDevicePath;
 446   Private->ControllerNameTable    = NULL;
 447
 448   Private->SoftwareLoopbackEnable = FALSE;
 449   Private->HardwareLoopbackEnable = FALSE;
 450   Private->HardwareFlowControl    = FALSE;
 451   Private->Fifo.First             = 0;
 452   Private->Fifo.Last              = 0;
 453   Private->Fifo.Surplus           = SERIAL_MAX_BUFFER_SIZE;
 454
 455   CopyMem (&Private->UartDevicePath, &Node, sizeof (UART_DEVICE_PATH));
 456
 457   AddUnicodeString2 (
 458     "eng",
 459     gWinNtSerialIoComponentName.SupportedLanguages,
 460     &Private->ControllerNameTable,
 461     WinNtIo->EnvString,
 462     TRUE
 463     );
 464   AddUnicodeString2 (
 465     "en",
 466     gWinNtSerialIoComponentName2.SupportedLanguages,
 467     &Private->ControllerNameTable,
 468     WinNtIo->EnvString,
 469     FALSE
 470     );
 471
 472
 473   Private->SerialIo.Revision      = SERIAL_IO_INTERFACE_REVISION;
 474   Private->SerialIo.Reset         = WinNtSerialIoReset;
 475   Private->SerialIo.SetAttributes = WinNtSerialIoSetAttributes;
 476   Private->SerialIo.SetControl    = WinNtSerialIoSetControl;
 477   Private->SerialIo.GetControl    = WinNtSerialIoGetControl;
 478   Private->SerialIo.Write         = WinNtSerialIoWrite;
 479   Private->SerialIo.Read          = WinNtSerialIoRead;
 480   Private->SerialIo.Mode          = &Private->SerialIoMode;
 481
 482   //
 483   // Build the device path by appending the UART node to the ParentDevicePath
 484   // from the WinNtIo handle. The Uart setings are zero here, since
 485   // SetAttribute() will update them to match the current setings.
 486   //
 487   Private->DevicePath = AppendDevicePathNode (
 488                           ParentDevicePath,
 489                           (EFI_DEVICE_PATH_PROTOCOL *) &Private->UartDevicePath
 490                           );
 491   if (Private->DevicePath == NULL) {
 492     Status = EFI_OUT_OF_RESOURCES;
 493     goto Error;
 494   }
 495
 496   //
 497   // Fill in Serial I/O Mode structure based on either the RemainingDevicePath or defaults.
 498   //
 499   Private->SerialIoMode.ControlMask       = SERIAL_CONTROL_MASK;
 500   Private->SerialIoMode.Timeout           = SERIAL_TIMEOUT_DEFAULT;
 501   Private->SerialIoMode.BaudRate          = Private->UartDevicePath.BaudRate;
 502   Private->SerialIoMode.ReceiveFifoDepth  = SERIAL_FIFO_DEFAULT;
 503   Private->SerialIoMode.DataBits          = Private->UartDevicePath.DataBits;
 504   Private->SerialIoMode.Parity            = Private->UartDevicePath.Parity;
 505   Private->SerialIoMode.StopBits          = Private->UartDevicePath.StopBits;
 506
 507   //
 508   // Issue a reset to initialize the COM port
 509   //
 510   Status = Private->SerialIo.Reset (&Private->SerialIo);
 511   if (EFI_ERROR (Status)) {
 512     goto Error;
 513   }
 514
 515   //
 516   // Create new child handle
 517   //
 518   Status = gBS->InstallMultipleProtocolInterfaces (
 519                   &Private->Handle,
 520                   &gEfiSerialIoProtocolGuid,
 521                   &Private->SerialIo,
 522                   &gEfiDevicePathProtocolGuid,
 523                   Private->DevicePath,
 524                   NULL
 525                   );
 526   if (EFI_ERROR (Status)) {
 527     goto Error;
 528   }
 529
 530   //
 531   // Open For Child Device
 532   //
 533   Status = gBS->OpenProtocol (
 534                   Handle,
 535                   &gEfiWinNtIoProtocolGuid,
 536                   (VOID **) &WinNtIo,
 537                   This->DriverBindingHandle,
 538                   Private->Handle,
 539                   EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
 540                   );
 541   if (EFI_ERROR (Status)) {
 542     goto Error;
 543   }
 544
 545   return EFI_SUCCESS;
 546
 547 Error:
 548   //
 549   // Use the Stop() function to free all resources allocated in Start()
 550   //
 551   if (Private != NULL) {
 552     if (Private->Handle != NULL) {
 553       This->Stop (This, Handle, 1, &Private->Handle);
 554     } else {
 555       if (NtHandle != INVALID_HANDLE_VALUE) {
 556         Private->WinNtThunk->CloseHandle (NtHandle);
 557       }
 558
 559       if (Private->DevicePath != NULL) {
 560         FreePool (Private->DevicePath);
 561       }
 562
 563       FreeUnicodeStringTable (Private->ControllerNameTable);
 564
 565       FreePool (Private);
 566     }
 567   }
 568
 569   This->Stop (This, Handle, 0, NULL);
 570
 571   return Status;
 572 }
 573
 574 EFI_STATUS
 575 EFIAPI
 576 WinNtSerialIoDriverBindingStop (
 577   IN  EFI_DRIVER_BINDING_PROTOCOL   *This,
 578   IN  EFI_HANDLE                    Handle,
 579   IN  UINTN                         NumberOfChildren,
 580   IN  EFI_HANDLE                    *ChildHandleBuffer
 581   )
 582 /*++
 583
 584 Routine Description:
 585
 586   TODO: Add function description
 587
 588 Arguments:
 589
 590   This              - TODO: add argument description
 591   Handle            - TODO: add argument description
 592   NumberOfChildren  - TODO: add argument description
 593   ChildHandleBuffer - TODO: add argument description
 594
 595 Returns:
 596
 597   EFI_DEVICE_ERROR - TODO: Add description for return value
 598   EFI_SUCCESS - TODO: Add description for return value
 599
 600 --*/
 601 {
 602   EFI_STATUS                    Status;
 603   UINTN                         Index;
 604   BOOLEAN                       AllChildrenStopped;
 605   EFI_SERIAL_IO_PROTOCOL        *SerialIo;
 606   WIN_NT_SERIAL_IO_PRIVATE_DATA *Private;
 607   EFI_WIN_NT_IO_PROTOCOL        *WinNtIo;
 608
 609   //
 610   // Complete all outstanding transactions to Controller.
 611   // Don't allow any new transaction to Controller to be started.
 612   //
 613
 614   if (NumberOfChildren == 0) {
 615     //
 616     // Close the bus driver
 617     //
 618     Status = gBS->CloseProtocol (
 619                     Handle,
 620                     &gEfiWinNtIoProtocolGuid,
 621                     This->DriverBindingHandle,
 622                     Handle
 623                     );
 624     Status = gBS->CloseProtocol (
 625                     Handle,
 626                     &gEfiDevicePathProtocolGuid,
 627                     This->DriverBindingHandle,
 628                     Handle
 629                     );
 630     return Status;
 631   }
 632
 633   AllChildrenStopped = TRUE;
 634
 635   for (Index = 0; Index < NumberOfChildren; Index++) {
 636     Status = gBS->OpenProtocol (
 637                     ChildHandleBuffer[Index],
 638                     &gEfiSerialIoProtocolGuid,
 639                     (VOID **) &SerialIo,
 640                     This->DriverBindingHandle,
 641                     Handle,
 642                     EFI_OPEN_PROTOCOL_GET_PROTOCOL
 643                     );
 644     if (!EFI_ERROR (Status)) {
 645       Private = WIN_NT_SERIAL_IO_PRIVATE_DATA_FROM_THIS (SerialIo);
 646
 647       ASSERT (Private->Handle == ChildHandleBuffer[Index]);
 648
 649       Status = gBS->CloseProtocol (
 650                       Handle,
 651                       &gEfiWinNtIoProtocolGuid,
 652                       This->DriverBindingHandle,
 653                       ChildHandleBuffer[Index]
 654                       );
 655
 656       Status = gBS->UninstallMultipleProtocolInterfaces (
 657                       ChildHandleBuffer[Index],
 658                       &gEfiSerialIoProtocolGuid,
 659                       &Private->SerialIo,
 660                       &gEfiDevicePathProtocolGuid,
 661                       Private->DevicePath,
 662                       NULL
 663                       );
 664
 665       if (EFI_ERROR (Status)) {
 666         gBS->OpenProtocol (
 667               Handle,
 668               &gEfiWinNtIoProtocolGuid,
 669               (VOID **) &WinNtIo,
 670               This->DriverBindingHandle,
 671               ChildHandleBuffer[Index],
 672               EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
 673               );
 674       } else {
 675         Private->WinNtThunk->CloseHandle (Private->NtHandle);
 676
 677         FreePool (Private->DevicePath);
 678
 679         FreeUnicodeStringTable (Private->ControllerNameTable);
 680
 681         FreePool (Private);
 682       }
 683     }
 684
 685     if (EFI_ERROR (Status)) {
 686       AllChildrenStopped = FALSE;
 687     }
 688   }
 689
 690   if (!AllChildrenStopped) {
 691     return EFI_DEVICE_ERROR;
 692   }
 693
 694   return EFI_SUCCESS;
 695 }
 696
 697 //
 698 // Serial IO Protocol member functions
 699 //
 700
 701 EFI_STATUS
 702 EFIAPI
 703 WinNtSerialIoReset (
 704   IN EFI_SERIAL_IO_PROTOCOL *This
 705   )
 706 /*++
 707
 708 Routine Description:
 709
 710   TODO: Add function description
 711
 712 Arguments:
 713
 714   This  - TODO: add argument description
 715
 716 Returns:
 717
 718   TODO: add return values
 719
 720 --*/
 721 {
 722   WIN_NT_SERIAL_IO_PRIVATE_DATA *Private;
 723   EFI_TPL                       Tpl;
 724
 725   Tpl     = gBS->RaiseTPL (TPL_NOTIFY);
 726
 727   Private = WIN_NT_SERIAL_IO_PRIVATE_DATA_FROM_THIS (This);
 728
 729   Private->WinNtThunk->PurgeComm (
 730                         Private->NtHandle,
 731                         PURGE_TXCLEAR | PURGE_RXCLEAR
 732                         );
 733
 734   gBS->RestoreTPL (Tpl);
 735
 736   return This->SetAttributes (
 737                 This,
 738                 This->Mode->BaudRate,
 739                 This->Mode->ReceiveFifoDepth,
 740                 This->Mode->Timeout,
 741                 (EFI_PARITY_TYPE)This->Mode->Parity,
 742                 (UINT8) This->Mode->DataBits,
 743                 (EFI_STOP_BITS_TYPE)This->Mode->StopBits
 744                 );
 745 }
 746
 747 EFI_STATUS
 748 EFIAPI
 749 WinNtSerialIoSetAttributes (
 750   IN EFI_SERIAL_IO_PROTOCOL *This,
 751   IN UINT64                 BaudRate,
 752   IN UINT32                 ReceiveFifoDepth,
 753   IN UINT32                 Timeout,
 754   IN EFI_PARITY_TYPE        Parity,
 755   IN UINT8                  DataBits,
 756   IN EFI_STOP_BITS_TYPE     StopBits
 757   )
 758 /*++
 759
 760 Routine Description:
 761
 762   This function is used to set the attributes.
 763
 764 Arguments:
 765
 766   This              - A pointer to the EFI_SERIAL_IO_PROTOCOL structrue.
 767   BaudRate          - The Baud rate of the serial device.
 768   ReceiveFifoDepth  - The request depth of fifo on receive side.
 769   Timeout           - the request timeout for a single charact.
 770   Parity            - The type of parity used in serial device.
 771   DataBits          - Number of deata bits used in serial device.
 772   StopBits          - Number of stop bits used in serial device.
 773
 774 Returns:
 775   Status code
 776
 777   None
 778
 779 --*/
 780 // TODO:    EFI_SUCCESS - add return value to function comment
 781 // TODO:    EFI_DEVICE_ERROR - add return value to function comment
 782 // TODO:    EFI_DEVICE_ERROR - add return value to function comment
 783 // TODO:    EFI_DEVICE_ERROR - add return value to function comment
 784 // TODO:    EFI_SUCCESS - add return value to function comment
 785 // TODO:    EFI_DEVICE_ERROR - add return value to function comment
 786 // TODO:    EFI_SUCCESS - add return value to function comment
 787 {
 788   EFI_STATUS                    Status;
 789   UINTN                         Index;
 790   WIN_NT_SERIAL_IO_PRIVATE_DATA *Private;
 791   COMMTIMEOUTS                  PortTimeOuts;
 792   DWORD                         ConvertedTime;
 793   BOOL                          Result;
 794   EFI_DEVICE_PATH_PROTOCOL      *NewDevicePath;
 795   EFI_TPL                       Tpl;
 796
 797   Private = WIN_NT_SERIAL_IO_PRIVATE_DATA_FROM_THIS (This);
 798
 799   //
 800   //  Some of our arguments have defaults if a null value is passed in, and
 801   //   we must set the default values if a null argument is passed in.
 802   //
 803   if (BaudRate == 0) {
 804     BaudRate = PcdGet64 (PcdUartDefaultBaudRate);
 805   }
 806
 807   if (ReceiveFifoDepth == 0) {
 808     ReceiveFifoDepth = SERIAL_FIFO_DEFAULT;
 809   }
 810
 811   if (Timeout == 0) {
 812     Timeout = SERIAL_TIMEOUT_DEFAULT;
 813   }
 814
 815   if (Parity == DefaultParity) {
 816     Parity = (EFI_PARITY_TYPE) (PcdGet8 (PcdUartDefaultParity));
 817   }
 818
 819   if (DataBits == 0) {
 820     DataBits = PcdGet8 (PcdUartDefaultDataBits);
 821   }
 822
 823   if (StopBits == DefaultStopBits) {
 824     StopBits = (EFI_STOP_BITS_TYPE) PcdGet8 (PcdUartDefaultStopBits);
 825   }
 826
 827   //
 828   // Make sure all parameters are valid
 829   //
 830   if ((BaudRate > SERIAL_PORT_MAX_BAUD_RATE) || (BaudRate < SERIAL_PORT_MIN_BAUD_RATE)) {
 831     return EFI_INVALID_PARAMETER;
 832   }
 833
 834   //
 835   //The lower baud rate supported by the serial device will be selected without exceeding the unsupported BaudRate parameter
 836   //
 837
 838   for (Index = 1; Index < (sizeof (mBaudRateCurrentSupport) / sizeof (mBaudRateCurrentSupport[0])); Index++) {
 839     if (BaudRate < mBaudRateCurrentSupport[Index]) {
 840       BaudRate = mBaudRateCurrentSupport[Index-1];
 841       break;
 842       }
 843   }
 844
 845   if ((ReceiveFifoDepth < 1) || (ReceiveFifoDepth > SERIAL_PORT_MAX_RECEIVE_FIFO_DEPTH)) {
 846     return EFI_INVALID_PARAMETER;
 847   }
 848
 849   if ((Timeout < SERIAL_PORT_MIN_TIMEOUT) || (Timeout > SERIAL_PORT_MAX_TIMEOUT)) {
 850     return EFI_INVALID_PARAMETER;
 851   }
 852
 853   if ((Parity < NoParity) || (Parity > SpaceParity)) {
 854     return EFI_INVALID_PARAMETER;
 855   }
 856
 857   if ((StopBits < OneStopBit) || (StopBits > TwoStopBits)) {
 858     return EFI_INVALID_PARAMETER;
 859   }
 860
 861   //
 862   // Now we only support DataBits=7,8.
 863   //
 864   if ((DataBits < 7) || (DataBits > 8)) {
 865     return EFI_INVALID_PARAMETER;
 866   }
 867
 868   //
 869   // Now we only support DataBits=7,8.
 870   // for DataBits = 6,7,8, StopBits can not set OneFiveStopBits.
 871   //
 872   if (StopBits == OneFiveStopBits) {
 873     return EFI_INVALID_PARAMETER;
 874   }
 875
 876   //
 877   // See if the new attributes already match the current attributes
 878   //
 879   if (Private->UartDevicePath.BaudRate       == BaudRate         &&
 880       Private->UartDevicePath.DataBits       == DataBits         &&
 881       Private->UartDevicePath.Parity         == Parity           &&
 882       Private->UartDevicePath.StopBits       == StopBits         &&
 883       Private->SerialIoMode.ReceiveFifoDepth == ReceiveFifoDepth &&
 884       Private->SerialIoMode.Timeout          == Timeout             ) {
 885     return EFI_SUCCESS;
 886   }
 887
 888   Tpl     = gBS->RaiseTPL (TPL_NOTIFY);
 889
 890   //
 891   //  Get current values from NT
 892   //
 893   ZeroMem (&Private->NtDCB, sizeof (DCB));
 894   Private->NtDCB.DCBlength = sizeof (DCB);
 895
 896   if (!Private->WinNtThunk->GetCommState (Private->NtHandle, &Private->NtDCB)) {
 897     Private->NtError = Private->WinNtThunk->GetLastError ();
 898     DEBUG ((EFI_D_ERROR, "SerialSetAttributes: GetCommState %d\n", Private->NtError));
 899     gBS->RestoreTPL (Tpl);
 900     return EFI_DEVICE_ERROR;
 901   }
 902
 903   //
 904   // Map EFI com setting to NT
 905   //
 906   Private->NtDCB.BaudRate         = ConvertBaud2Nt (BaudRate);
 907   Private->NtDCB.ByteSize         = ConvertData2Nt (DataBits);
 908   Private->NtDCB.Parity           = ConvertParity2Nt (Parity);
 909   Private->NtDCB.StopBits         = ConvertStop2Nt (StopBits);
 910
 911   Private->NtDCB.fBinary          = TRUE;
 912   Private->NtDCB.fParity          = Private->NtDCB.Parity == NOPARITY ? FALSE : TRUE;
 913   Private->NtDCB.fOutxCtsFlow     = FALSE;
 914   Private->NtDCB.fOutxDsrFlow     = FALSE;
 915   Private->NtDCB.fDtrControl      = DTR_CONTROL_ENABLE;
 916   Private->NtDCB.fDsrSensitivity  = FALSE;
 917   Private->NtDCB.fOutX            = FALSE;
 918   Private->NtDCB.fInX             = FALSE;
 919   Private->NtDCB.fRtsControl      = RTS_CONTROL_ENABLE;
 920   Private->NtDCB.fNull            = FALSE;
 921
 922   //
 923   //  Set new values
 924   //
 925   Result = Private->WinNtThunk->SetCommState (Private->NtHandle, &Private->NtDCB);
 926   if (!Result) {
 927     Private->NtError = Private->WinNtThunk->GetLastError ();
 928     DEBUG ((EFI_D_ERROR, "SerialSetAttributes: SetCommState %d\n", Private->NtError));
 929     gBS->RestoreTPL (Tpl);
 930     return EFI_DEVICE_ERROR;
 931   }
 932
 933   //
 934   //  Set com port read/write timeout values
 935   //
 936   ConvertedTime = ConvertTime2Nt (Timeout);
 937   PortTimeOuts.ReadIntervalTimeout = MAXDWORD;
 938   PortTimeOuts.ReadTotalTimeoutMultiplier = 0;
 939   PortTimeOuts.ReadTotalTimeoutConstant = ConvertedTime;
 940   PortTimeOuts.WriteTotalTimeoutMultiplier = ConvertedTime == 0 ? 1 : ConvertedTime;
 941   PortTimeOuts.WriteTotalTimeoutConstant = 0;
 942
 943   if (!Private->WinNtThunk->SetCommTimeouts (Private->NtHandle, &PortTimeOuts)) {
 944     Private->NtError = Private->WinNtThunk->GetLastError ();
 945     DEBUG ((EFI_D_ERROR, "SerialSetAttributes: SetCommTimeouts %d\n", Private->NtError));
 946     gBS->RestoreTPL (Tpl);
 947     return EFI_DEVICE_ERROR;
 948   }
 949
 950   //
 951   //  Update mode
 952   //
 953   Private->SerialIoMode.BaudRate          = BaudRate;
 954   Private->SerialIoMode.ReceiveFifoDepth  = ReceiveFifoDepth;
 955   Private->SerialIoMode.Timeout           = Timeout;
 956   Private->SerialIoMode.Parity            = Parity;
 957   Private->SerialIoMode.DataBits          = DataBits;
 958   Private->SerialIoMode.StopBits          = StopBits;
 959
 960   //
 961   // See if Device Path Node has actually changed
 962   //
 963   if (Private->UartDevicePath.BaudRate     == BaudRate &&
 964       Private->UartDevicePath.DataBits     == DataBits &&
 965       Private->UartDevicePath.Parity       == Parity   &&
 966       Private->UartDevicePath.StopBits     == StopBits    ) {
 967     gBS->RestoreTPL(Tpl);
 968     return EFI_SUCCESS;
 969   }
 970
 971   //
 972   // Update the device path
 973   //
 974   Private->UartDevicePath.BaudRate  = BaudRate;
 975   Private->UartDevicePath.DataBits  = DataBits;
 976   Private->UartDevicePath.Parity    = (UINT8) Parity;
 977   Private->UartDevicePath.StopBits  = (UINT8) StopBits;
 978
 979   NewDevicePath = AppendDevicePathNode (
 980                     Private->ParentDevicePath,
 981                     (EFI_DEVICE_PATH_PROTOCOL *) &Private->UartDevicePath
 982                     );
 983   if (NewDevicePath == NULL) {
 984     gBS->RestoreTPL (Tpl);
 985     return EFI_DEVICE_ERROR;
 986   }
 987
 988   if (Private->Handle != NULL) {
 989     Status = gBS->ReinstallProtocolInterface (
 990                     Private->Handle,
 991                     &gEfiDevicePathProtocolGuid,
 992                     Private->DevicePath,
 993                     NewDevicePath
 994                     );
 995     if (EFI_ERROR (Status)) {
 996       gBS->RestoreTPL (Tpl);
 997       return Status;
 998     }
 999   }
1000
1001   if (Private->DevicePath != NULL) {
1002     FreePool (Private->DevicePath);
1003   }
1004
1005   Private->DevicePath = NewDevicePath;
1006
1007   gBS->RestoreTPL (Tpl);
1008
1009   return EFI_SUCCESS;
1010 }
1011
1012 EFI_STATUS
1013 EFIAPI
1014 WinNtSerialIoSetControl (
1015   IN EFI_SERIAL_IO_PROTOCOL *This,
1016   IN UINT32                 Control
1017   )
1018 /*++
1019
1020 Routine Description:
1021
1022   TODO: Add function description
1023
1024 Arguments:
1025
1026   This    - TODO: add argument description
1027   Control - TODO: add argument description
1028
1029 Returns:
1030
1031   EFI_DEVICE_ERROR - TODO: Add description for return value
1032   EFI_DEVICE_ERROR - TODO: Add description for return value
1033   EFI_SUCCESS - TODO: Add description for return value
1034
1035 --*/
1036 {
1037   WIN_NT_SERIAL_IO_PRIVATE_DATA *Private;
1038   BOOL                          Result;
1039   DCB                           Dcb;
1040   EFI_TPL                       Tpl;
1041
1042   //
1043   // first determine the parameter is invalid
1044   //
1045   if (Control & (~(EFI_SERIAL_REQUEST_TO_SEND | EFI_SERIAL_DATA_TERMINAL_READY |
1046                    EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE | EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE |
1047                    EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE))) {
1048     return EFI_UNSUPPORTED;
1049   }
1050
1051   Tpl     = gBS->RaiseTPL (TPL_NOTIFY);
1052
1053   Private = WIN_NT_SERIAL_IO_PRIVATE_DATA_FROM_THIS (This);
1054
1055   Result  = Private->WinNtThunk->GetCommState (Private->NtHandle, &Dcb);
1056
1057   if (!Result) {
1058     Private->NtError = Private->WinNtThunk->GetLastError ();
1059     DEBUG ((EFI_D_ERROR, "SerialSetControl: GetCommState %d\n", Private->NtError));
1060     gBS->RestoreTPL (Tpl);
1061     return EFI_DEVICE_ERROR;
1062   }
1063
1064   Dcb.fRtsControl                 = RTS_CONTROL_DISABLE;
1065   Dcb.fDtrControl                 = DTR_CONTROL_DISABLE;
1066   Private->HardwareFlowControl    = FALSE;
1067   Private->SoftwareLoopbackEnable = FALSE;
1068   Private->HardwareLoopbackEnable = FALSE;
1069
1070   if (Control & EFI_SERIAL_REQUEST_TO_SEND) {
1071     Dcb.fRtsControl = RTS_CONTROL_ENABLE;
1072   }
1073
1074   if (Control & EFI_SERIAL_DATA_TERMINAL_READY) {
1075     Dcb.fDtrControl = DTR_CONTROL_ENABLE;
1076   }
1077
1078   if (Control & EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE) {
1079     Private->HardwareFlowControl = TRUE;
1080   }
1081
1082   if (Control & EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE) {
1083     Private->SoftwareLoopbackEnable = TRUE;
1084   }
1085
1086   if (Control & EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE) {
1087     Private->HardwareLoopbackEnable = TRUE;
1088   }
1089
1090   Result = Private->WinNtThunk->SetCommState (
1091                                   Private->NtHandle,
1092                                   &Dcb
1093                                   );
1094
1095   if (!Result) {
1096     Private->NtError = Private->WinNtThunk->GetLastError ();
1097     DEBUG ((EFI_D_ERROR, "SerialSetControl: SetCommState %d\n", Private->NtError));
1098     gBS->RestoreTPL (Tpl);
1099     return EFI_DEVICE_ERROR;
1100   }
1101
1102   gBS->RestoreTPL (Tpl);
1103
1104   return EFI_SUCCESS;
1105 }
1106
1107 EFI_STATUS
1108 EFIAPI
1109 WinNtSerialIoGetControl (
1110   IN  EFI_SERIAL_IO_PROTOCOL  *This,
1111   OUT UINT32                  *Control
1112   )
1113 /*++
1114
1115 Routine Description:
1116
1117   TODO: Add function description
1118
1119 Arguments:
1120
1121   This    - TODO: add argument description
1122   Control - TODO: add argument description
1123
1124 Returns:
1125
1126   EFI_DEVICE_ERROR - TODO: Add description for return value
1127   EFI_DEVICE_ERROR - TODO: Add description for return value
1128   EFI_DEVICE_ERROR - TODO: Add description for return value
1129   EFI_SUCCESS - TODO: Add description for return value
1130
1131 --*/
1132 {
1133   WIN_NT_SERIAL_IO_PRIVATE_DATA *Private;
1134   DWORD                         ModemStatus;
1135   DWORD                         Errors;
1136   UINT32                        Bits;
1137   DCB                           Dcb;
1138   EFI_TPL                       Tpl;
1139
1140   Tpl     = gBS->RaiseTPL (TPL_NOTIFY);
1141
1142   Private = WIN_NT_SERIAL_IO_PRIVATE_DATA_FROM_THIS (This);
1143
1144   //
1145   //  Get modem status
1146   //
1147   if (!Private->WinNtThunk->GetCommModemStatus (Private->NtHandle, &ModemStatus)) {
1148     Private->NtError = Private->WinNtThunk->GetLastError ();
1149     gBS->RestoreTPL (Tpl);
1150     return EFI_DEVICE_ERROR;
1151   }
1152
1153   Bits = 0;
1154   if (ModemStatus & MS_CTS_ON) {
1155     Bits |= EFI_SERIAL_CLEAR_TO_SEND;
1156   }
1157
1158   if (ModemStatus & MS_DSR_ON) {
1159     Bits |= EFI_SERIAL_DATA_SET_READY;
1160   }
1161
1162   if (ModemStatus & MS_RING_ON) {
1163     Bits |= EFI_SERIAL_RING_INDICATE;
1164   }
1165
1166   if (ModemStatus & MS_RLSD_ON) {
1167     Bits |= EFI_SERIAL_CARRIER_DETECT;
1168   }
1169
1170   //
1171   // Get ctrl status
1172   //
1173   if (!Private->WinNtThunk->GetCommState (Private->NtHandle, &Dcb)) {
1174     Private->NtError = Private->WinNtThunk->GetLastError ();
1175     DEBUG ((EFI_D_ERROR, "SerialGetControl: GetCommState %d\n", Private->NtError));
1176     gBS->RestoreTPL (Tpl);
1177     return EFI_DEVICE_ERROR;
1178   }
1179
1180   if (Dcb.fDtrControl == DTR_CONTROL_ENABLE) {
1181     Bits |= EFI_SERIAL_DATA_TERMINAL_READY;
1182   }
1183
1184   if (Dcb.fRtsControl == RTS_CONTROL_ENABLE) {
1185     Bits |= EFI_SERIAL_REQUEST_TO_SEND;
1186   }
1187
1188   if (Private->HardwareFlowControl) {
1189     Bits |= EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE;
1190   }
1191
1192   if (Private->SoftwareLoopbackEnable) {
1193     Bits |= EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE;
1194   }
1195
1196   if (Private->HardwareLoopbackEnable) {
1197     Bits |= EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE;
1198   }
1199
1200   //
1201   //  Get input buffer status
1202   //
1203   if (!Private->WinNtThunk->ClearCommError (Private->NtHandle, &Errors, &Private->NtComStatus)) {
1204     Private->NtError = Private->WinNtThunk->GetLastError ();
1205     DEBUG ((EFI_D_ERROR, "SerialGetControl: ClearCommError %d\n", Private->NtError));
1206     gBS->RestoreTPL (Tpl);
1207     return EFI_DEVICE_ERROR;
1208   }
1209
1210   if (Private->NtComStatus.cbInQue == 0) {
1211     Bits |= EFI_SERIAL_INPUT_BUFFER_EMPTY;
1212   }
1213
1214   *Control = Bits;
1215
1216   gBS->RestoreTPL (Tpl);
1217
1218   return EFI_SUCCESS;
1219 }
1220
1221 EFI_STATUS
1222 EFIAPI
1223 WinNtSerialIoWrite (
1224   IN EFI_SERIAL_IO_PROTOCOL   *This,
1225   IN OUT UINTN                *BufferSize,
1226   IN VOID                     *Buffer
1227   )
1228 /*++
1229
1230 Routine Description:
1231
1232   TODO: Add function description
1233
1234 Arguments:
1235
1236   This        - TODO: add argument description
1237   BufferSize  - TODO: add argument description
1238   Buffer      - TODO: add argument description
1239
1240 Returns:
1241
1242   EFI_DEVICE_ERROR - TODO: Add description for return value
1243   EFI_SUCCESS - TODO: Add description for return value
1244
1245 --*/
1246 {
1247   WIN_NT_SERIAL_IO_PRIVATE_DATA *Private;
1248   UINT8                         *ByteBuffer;
1249   UINTN                         TotalBytesWritten;
1250   DWORD                         BytesToGo;
1251   DWORD                         BytesWritten;
1252   BOOL                          Result;
1253   UINT32                        Index;
1254   UINT32                        Control;
1255   EFI_TPL                       Tpl;
1256
1257   Tpl               = gBS->RaiseTPL (TPL_NOTIFY);
1258
1259   Private           = WIN_NT_SERIAL_IO_PRIVATE_DATA_FROM_THIS (This);
1260
1261   ByteBuffer        = (UINT8 *) Buffer;
1262   TotalBytesWritten = 0;
1263
1264   if (Private->SoftwareLoopbackEnable || Private->HardwareLoopbackEnable) {
1265     for (Index = 0; Index < *BufferSize; Index++) {
1266       if (IsaSerialFifoAdd (&Private->Fifo, ByteBuffer[Index]) == EFI_SUCCESS) {
1267         TotalBytesWritten++;
1268       } else {
1269         break;
1270       }
1271     }
1272   } else {
1273     BytesToGo = (DWORD) (*BufferSize);
1274
1275     do {
1276       if (Private->HardwareFlowControl) {
1277         //
1278         // Send RTS
1279         //
1280         WinNtSerialIoGetControl (&Private->SerialIo, &Control);
1281         Control |= EFI_SERIAL_REQUEST_TO_SEND;
1282         WinNtSerialIoSetControl (&Private->SerialIo, Control);
1283       }
1284
1285       //
1286       //  Do the write
1287       //
1288       Result = Private->WinNtThunk->WriteFile (
1289                                       Private->NtHandle,
1290                                       &ByteBuffer[TotalBytesWritten],
1291                                       BytesToGo,
1292                                       &BytesWritten,
1293                                       NULL
1294                                       );
1295
1296       if (Private->HardwareFlowControl) {
1297         //
1298         // Assert RTS
1299         //
1300         WinNtSerialIoGetControl (&Private->SerialIo, &Control);
1301         Control &= ~ (UINT32) EFI_SERIAL_REQUEST_TO_SEND;
1302         WinNtSerialIoSetControl (&Private->SerialIo, Control);
1303       }
1304
1305       TotalBytesWritten += BytesWritten;
1306       BytesToGo -= BytesWritten;
1307       if (!Result) {
1308         Private->NtError = Private->WinNtThunk->GetLastError ();
1309         DEBUG ((EFI_D_ERROR, "SerialWrite: FileWrite %d\n", Private->NtError));
1310         *BufferSize = TotalBytesWritten;
1311         gBS->RestoreTPL (Tpl);
1312         return EFI_DEVICE_ERROR;
1313       }
1314     } while (BytesToGo > 0);
1315   }
1316
1317   *BufferSize = TotalBytesWritten;
1318
1319   gBS->RestoreTPL (Tpl);
1320
1321   return EFI_SUCCESS;
1322 }
1323
1324 EFI_STATUS
1325 EFIAPI
1326 WinNtSerialIoRead (
1327   IN  EFI_SERIAL_IO_PROTOCOL  *This,
1328   IN  OUT UINTN               *BufferSize,
1329   OUT VOID                    *Buffer
1330   )
1331 /*++
1332
1333 Routine Description:
1334
1335   TODO: Add function description
1336
1337 Arguments:
1338
1339   This        - TODO: add argument description
1340   BufferSize  - TODO: add argument description
1341   Buffer      - TODO: add argument description
1342
1343 Returns:
1344
1345   EFI_DEVICE_ERROR - TODO: Add description for return value
1346
1347 --*/
1348 {
1349   WIN_NT_SERIAL_IO_PRIVATE_DATA *Private;
1350   BOOL                          Result;
1351   DWORD                         BytesRead;
1352   EFI_STATUS                    Status;
1353   UINT32                        Index;
1354   UINT8                         Data;
1355   UINT32                        Control;
1356   EFI_TPL                       Tpl;
1357
1358   Tpl     = gBS->RaiseTPL (TPL_NOTIFY);
1359
1360   Private = WIN_NT_SERIAL_IO_PRIVATE_DATA_FROM_THIS (This);
1361
1362   //
1363   //  Do the read
1364   //
1365   if (Private->SoftwareLoopbackEnable || Private->HardwareLoopbackEnable) {
1366     for (Index = 0, BytesRead = 0; Index < *BufferSize; Index++) {
1367       if (IsaSerialFifoRemove (&Private->Fifo, &Data) == EFI_SUCCESS) {
1368         ((UINT8 *) Buffer)[Index] = Data;
1369         BytesRead++;
1370       } else {
1371         break;
1372       }
1373     }
1374   } else {
1375     if (Private->HardwareFlowControl) {
1376       WinNtSerialIoGetControl (&Private->SerialIo, &Control);
1377       Control |= EFI_SERIAL_DATA_TERMINAL_READY;
1378       WinNtSerialIoSetControl (&Private->SerialIo, Control);
1379     }
1380
1381     Result = Private->WinNtThunk->ReadFile (
1382                                     Private->NtHandle,
1383                                     Buffer,
1384                                     (DWORD) *BufferSize,
1385                                     &BytesRead,
1386                                     NULL
1387                                     );
1388
1389     if (Private->HardwareFlowControl) {
1390       WinNtSerialIoGetControl (&Private->SerialIo, &Control);
1391       Control &= ~ (UINT32) EFI_SERIAL_DATA_TERMINAL_READY;
1392       WinNtSerialIoSetControl (&Private->SerialIo, Control);
1393     }
1394
1395     if (!Result) {
1396       Private->NtError = Private->WinNtThunk->GetLastError ();
1397       gBS->RestoreTPL (Tpl);
1398       return EFI_DEVICE_ERROR;
1399     }
1400   }
1401
1402   if (BytesRead != *BufferSize) {
1403     Status = EFI_TIMEOUT;
1404   } else {
1405     Status = EFI_SUCCESS;
1406   }
1407
1408   *BufferSize = (UINTN) BytesRead;
1409
1410   gBS->RestoreTPL (Tpl);
1411
1412   return Status;
1413 }
1414
1415 BOOLEAN
1416 IsaSerialFifoFull (
1417   IN SERIAL_DEV_FIFO *Fifo
1418   )
1419 /*++
1420
1421   Routine Description:
1422   Detect whether specific FIFO is full or not
1423
1424   Arguments:
1425   Fifo  SERIAL_DEV_FIFO *: A pointer to the Data Structure SERIAL_DEV_FIFO
1426
1427   Returns:
1428   TRUE:  the FIFO is full
1429   FALSE: the FIFO is not full
1430
1431 --*/
1432 {
1433   if (Fifo->Surplus == 0) {
1434     return TRUE;
1435   }
1436
1437   return FALSE;
1438 }
1439
1440 BOOLEAN
1441 IsaSerialFifoEmpty (
1442   IN SERIAL_DEV_FIFO *Fifo
1443   )
1444 /*++
1445
1446   Routine Description:
1447   Detect whether specific FIFO is empty or not
1448
1449   Arguments:
1450     Fifo  SERIAL_DEV_FIFO *: A pointer to the Data Structure SERIAL_DEV_FIFO
1451
1452   Returns:
1453     TRUE:  the FIFO is empty
1454     FALSE: the FIFO is not empty
1455
1456 --*/
1457 {
1458   if (Fifo->Surplus == SERIAL_MAX_BUFFER_SIZE) {
1459     return TRUE;
1460   }
1461
1462   return FALSE;
1463 }
1464
1465 EFI_STATUS
1466 IsaSerialFifoAdd (
1467   IN SERIAL_DEV_FIFO *Fifo,
1468   IN UINT8           Data
1469   )
1470 /*++
1471
1472   Routine Description:
1473   Add data to specific FIFO
1474
1475   Arguments:
1476     Fifo  SERIAL_DEV_FIFO *: A pointer to the Data Structure SERIAL_DEV_FIFO
1477     Data  UINT8: the data added to FIFO
1478
1479   Returns:
1480     EFI_SUCCESS:  Add data to specific FIFO successfully
1481     EFI_OUT_RESOURCE: Failed to add data because FIFO is already full
1482
1483 --*/
1484 // TODO:    EFI_OUT_OF_RESOURCES - add return value to function comment
1485 {
1486   //
1487   // if FIFO full can not add data
1488   //
1489   if (IsaSerialFifoFull (Fifo)) {
1490     return EFI_OUT_OF_RESOURCES;
1491   }
1492
1493   //
1494   // FIFO is not full can add data
1495   //
1496   Fifo->Data[Fifo->Last] = Data;
1497   Fifo->Surplus--;
1498   Fifo->Last++;
1499   if (Fifo->Last >= SERIAL_MAX_BUFFER_SIZE) {
1500     Fifo->Last = 0;
1501   }
1502
1503   return EFI_SUCCESS;
1504 }
1505
1506 EFI_STATUS
1507 IsaSerialFifoRemove (
1508   IN  SERIAL_DEV_FIFO *Fifo,
1509   OUT UINT8           *Data
1510   )
1511 /*++
1512
1513   Routine Description:
1514   Remove data from specific FIFO
1515
1516   Arguments:
1517     Fifo  SERIAL_DEV_FIFO *: A pointer to the Data Structure SERIAL_DEV_FIFO
1518     Data  UINT8*: the data removed from FIFO
1519
1520   Returns:
1521     EFI_SUCCESS:  Remove data from specific FIFO successfully
1522     EFI_OUT_RESOURCE: Failed to remove data because FIFO is empty
1523
1524 --*/
1525 // TODO:    EFI_OUT_OF_RESOURCES - add return value to function comment
1526 {
1527   //
1528   // if FIFO is empty, no data can remove
1529   //
1530   if (IsaSerialFifoEmpty (Fifo)) {
1531     return EFI_OUT_OF_RESOURCES;
1532   }
1533
1534   //
1535   // FIFO is not empty, can remove data
1536   //
1537   *Data = Fifo->Data[Fifo->First];
1538   Fifo->Surplus++;
1539   Fifo->First++;
1540   if (Fifo->First >= SERIAL_MAX_BUFFER_SIZE) {
1541     Fifo->First = 0;
1542   }
1543
1544   return EFI_SUCCESS;
1545 }