diff mbox series

[edk2,v2,1/1] EmbeddedPkg/Drivers: add virtual keyboard driver

Message ID 1520515702-29405-1-git-send-email-haojian.zhuang@linaro.org
State Superseded
Headers show
Series add virtual keyboard driver | expand

Commit Message

Haojian Zhuang March 8, 2018, 1:28 p.m. UTC
This driver is used to simulate a keyboard. For example, user
could read GPIO setting or data from RAM address. If the value
matches the expected pattern, it could trigger a key pressed
event.

User needs to implement hooks of PLATFORM_VIRTUAL_KBD_PROTOCOL.
There're 4 hooks in this protocol.
Register(): Quote the interface that user needs. For example, user
needs to locate GPIO protocol if he wants to simulate a GPIO value
as a key.
Reset(): Do the initialization before reading value.
Query(): Read value. If the value matches the expected pattern,
trigger a key pressed event.
Clear(): Clean the value if necessary.

Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
---
 EmbeddedPkg/EmbeddedPkg.dec                                   |    1 +
 EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboardDxe.inf |   60 +
 EmbeddedPkg/Drivers/VirtualKeyboardDxe/ComponentName.h        |  154 +++
 EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboard.h      |  544 +++++++++
 EmbeddedPkg/Include/Protocol/PlatformVirtualKeyboard.h        |   65 ++
 EmbeddedPkg/Drivers/VirtualKeyboardDxe/ComponentName.c        |  188 ++++
 EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboard.c      | 1149 ++++++++++++++++++++
 7 files changed, 2161 insertions(+)
diff mbox series

Patch

diff --git a/EmbeddedPkg/EmbeddedPkg.dec b/EmbeddedPkg/EmbeddedPkg.dec
index e48ce2e95bf7..eb135340b173 100644
--- a/EmbeddedPkg/EmbeddedPkg.dec
+++ b/EmbeddedPkg/EmbeddedPkg.dec
@@ -80,6 +80,7 @@  [Protocols.common]
   gUsbDeviceProtocolGuid =  { 0x021bd2ca, 0x51d2, 0x11e3, {0x8e, 0x56, 0xb7, 0x54, 0x17, 0xc7,  0x0b, 0x44 }}
   gPlatformGpioProtocolGuid = { 0x52ce9845, 0x5af4, 0x43e2, {0xba, 0xfd, 0x23, 0x08, 0x12, 0x54, 0x7a, 0xc2 }}
   gAndroidBootImgProtocolGuid = { 0x9859bb19, 0x407c, 0x4f8b, {0xbc, 0xe1, 0xf8, 0xda, 0x65, 0x65, 0xf4, 0xa5 }}
+  gPlatformVirtualKeyboardProtocolGuid = { 0x0e3606d2, 0x1dc3, 0x4e6f, { 0xbe, 0x65, 0x39, 0x49, 0x82, 0xa2, 0x65, 0x47 }}
 
 [Ppis]
   gEdkiiEmbeddedGpioPpiGuid = { 0x21c3b115, 0x4e0b, 0x470c, { 0x85, 0xc7, 0xe1, 0x05, 0xa5, 0x75, 0xc9, 0x7b }}
diff --git a/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboardDxe.inf b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboardDxe.inf
new file mode 100644
index 000000000000..deb54dab6592
--- /dev/null
+++ b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboardDxe.inf
@@ -0,0 +1,60 @@ 
+## @file
+# Virtual Keyboard driver.
+#
+# Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
+#
+# 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.
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010019
+  BASE_NAME                      = VirtualKeyboardDxe
+  FILE_GUID                      = 88079b18-b42b-44aa-a6f2-b83911075e89
+  MODULE_TYPE                    = UEFI_DRIVER
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = InitializeVirtualKeyboard
+
+#
+# The following information is for reference only and not required by the build tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64 IPF ARM AARCH64
+#
+#  DRIVER_BINDING                = gVirtualKeyboardDriverBinding
+#  COMPONENT_NAME                = gVirtualKeyboardComponentName
+#
+
+[Sources.common]
+  ComponentName.c
+  VirtualKeyboard.c
+
+[Packages]
+  EmbeddedPkg/EmbeddedPkg.dec
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+  BaseLib
+  BaseMemoryLib
+  DebugLib
+  IoLib
+  ReportStatusCodeLib
+  UefiDriverEntryPoint
+  UefiBootServicesTableLib
+  UefiLib
+
+[Protocols]
+  gEfiDriverBindingProtocolGuid
+  gEfiSimpleTextInProtocolGuid
+  gEfiSimpleTextInputExProtocolGuid
+  gPlatformVirtualKeyboardProtocolGuid
+
+[Depex]
+  TRUE
diff --git a/EmbeddedPkg/Drivers/VirtualKeyboardDxe/ComponentName.h b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/ComponentName.h
new file mode 100644
index 000000000000..94bef285086a
--- /dev/null
+++ b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/ComponentName.h
@@ -0,0 +1,154 @@ 
+/** @file
+
+Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
+
+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.
+
+**/
+
+#ifndef _VIRTUAL_KEYBOARD_COMPONENT_NAME_H_
+#define _VIRTUAL_KEYBOARD_COMPONENT_NAME_H_
+
+
+extern EFI_COMPONENT_NAME_PROTOCOL   gVirtualKeyboardComponentName;
+extern EFI_COMPONENT_NAME2_PROTOCOL  gVirtualKeyboardComponentName2;
+
+//
+// EFI Component Name Functions
+//
+/**
+  Retrieves a Unicode string that is the user readable name of the driver.
+
+  This function retrieves the user readable name of a driver in the form of a
+  Unicode string. If the driver specified by This has a user readable name in
+  the language specified by Language, then a pointer to the driver name is
+  returned in DriverName, and EFI_SUCCESS is returned. If the driver specified
+  by This does not support the language specified by Language,
+  then EFI_UNSUPPORTED is returned.
+
+  @param  This[in]              A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
+                                EFI_COMPONENT_NAME_PROTOCOL instance.
+
+  @param  Language[in]          A pointer to a Null-terminated ASCII string
+                                array indicating the language. This is the
+                                language of the driver name that the caller is
+                                requesting, and it must match one of the
+                                languages specified in SupportedLanguages. The
+                                number of languages supported by a driver is up
+                                to the driver writer. Language is specified
+                                in RFC 4646 or ISO 639-2 language code format.
+
+  @param  DriverName[out]       A pointer to the Unicode string to return.
+                                This Unicode string is the name of the
+                                driver specified by This in the language
+                                specified by Language.
+
+  @retval EFI_SUCCESS           The Unicode string for the Driver specified by
+                                This and the language specified by Language was
+                                returned in DriverName.
+
+  @retval EFI_INVALID_PARAMETER Language is NULL.
+
+  @retval EFI_INVALID_PARAMETER DriverName is NULL.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This does not support
+                                the language specified by Language.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardComponentNameGetDriverName (
+  IN  EFI_COMPONENT_NAME_PROTOCOL  *This,
+  IN  CHAR8                        *Language,
+  OUT CHAR16                       **DriverName
+  );
+
+
+/**
+  Retrieves a Unicode string that is the user readable name of the controller
+  that is being managed by a driver.
+
+  This function retrieves the user readable name of the controller specified by
+  ControllerHandle and ChildHandle in the form of a Unicode string. If the
+  driver specified by This has a user readable name in the language specified by
+  Language, then a pointer to the controller name is returned in ControllerName,
+  and EFI_SUCCESS is returned.  If the driver specified by This is not currently
+  managing the controller specified by ControllerHandle and ChildHandle,
+  then EFI_UNSUPPORTED is returned.  If the driver specified by This does not
+  support the language specified by Language, then EFI_UNSUPPORTED is returned.
+
+  @param  This[in]              A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
+                                EFI_COMPONENT_NAME_PROTOCOL instance.
+
+  @param  ControllerHandle[in]  The handle of a controller that the driver
+                                specified by This is managing.  This handle
+                                specifies the controller whose name is to be
+                                returned.
+
+  @param  ChildHandle[in]       The handle of the child controller to retrieve
+                                the name of.  This is an optional parameter that
+                                may be NULL.  It will be NULL for device
+                                drivers.  It will also be NULL for a bus drivers
+                                that wish to retrieve the name of the bus
+                                controller.  It will not be NULL for a bus
+                                driver that wishes to retrieve the name of a
+                                child controller.
+
+  @param  Language[in]          A pointer to a Null-terminated ASCII string
+                                array indicating the language.  This is the
+                                language of the driver name that the caller is
+                                requesting, and it must match one of the
+                                languages specified in SupportedLanguages. The
+                                number of languages supported by a driver is up
+                                to the driver writer. Language is specified in
+                                RFC 4646 or ISO 639-2 language code format.
+
+  @param  ControllerName[out]   A pointer to the Unicode string to return.
+                                This Unicode string is the name of the
+                                controller specified by ControllerHandle and
+                                ChildHandle in the language specified by
+                                Language from the point of view of the driver
+                                specified by This.
+
+  @retval EFI_SUCCESS           The Unicode string for the user readable name in
+                                the language specified by Language for the
+                                driver specified by This was returned in
+                                DriverName.
+
+  @retval EFI_INVALID_PARAMETER ControllerHandle is NULL.
+
+  @retval EFI_INVALID_PARAMETER ChildHandle is not NULL and it is not a valid
+                                EFI_HANDLE.
+
+  @retval EFI_INVALID_PARAMETER Language is NULL.
+
+  @retval EFI_INVALID_PARAMETER ControllerName is NULL.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This is not currently
+                                managing the controller specified by
+                                ControllerHandle and ChildHandle.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This does not support
+                                the language specified by Language.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardComponentNameGetControllerName (
+  IN  EFI_COMPONENT_NAME_PROTOCOL                     *This,
+  IN  EFI_HANDLE                                      ControllerHandle,
+  IN  EFI_HANDLE                                      ChildHandle        OPTIONAL,
+  IN  CHAR8                                           *Language,
+  OUT CHAR16                                          **ControllerName
+  );
+
+
+#endif
diff --git a/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboard.h b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboard.h
new file mode 100644
index 000000000000..6dc8264521a6
--- /dev/null
+++ b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboard.h
@@ -0,0 +1,544 @@ 
+/** @file
+
+Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
+
+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.
+
+**/
+
+#ifndef _VIRTUAL_KEYBOARD_H_
+#define _VIRTUAL_KEYBOARD_H_
+
+
+#include <Guid/StatusCodeDataTypeId.h>
+#include <Protocol/DevicePath.h>
+#include <Protocol/PlatformVirtualKeyboard.h>
+#include <Protocol/SimpleTextIn.h>
+#include <Protocol/SimpleTextInEx.h>
+
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/IoLib.h>
+#include <Library/PcdLib.h>
+#include <Library/ReportStatusCodeLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiDriverEntryPoint.h>
+#include <Library/UefiLib.h>
+
+//
+// Driver Binding Externs
+//
+extern EFI_DRIVER_BINDING_PROTOCOL  gVirtualKeyboardDriverBinding;
+extern EFI_COMPONENT_NAME_PROTOCOL  gVirtualKeyboardComponentName;
+extern EFI_COMPONENT_NAME2_PROTOCOL gVirtualKeyboardComponentName2;
+
+
+//
+// VIRTUAL Keyboard Defines
+//
+#define CHAR_SCANCODE                        0xe0
+#define CHAR_ESC                             0x1b
+
+#define KEYBOARD_TIMEOUT                     65536   // 0.07s
+#define KEYBOARD_WAITFORVALUE_TIMEOUT        1000000 // 1s
+#define KEYBOARD_BAT_TIMEOUT                 4000000 // 4s
+#define KEYBOARD_TIMER_INTERVAL              500000  // 0.5s
+
+#define QUEUE_MAX_COUNT                      32
+
+#define KEYBOARD_SCAN_CODE_MAX_COUNT         32
+
+//
+// VIRTUAL Keyboard Device Structure
+//
+#define VIRTUAL_KEYBOARD_DEV_SIGNATURE SIGNATURE_32 ('V', 'K', 'B', 'D')
+#define VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE SIGNATURE_32 ('v', 'k', 'c', 'n')
+
+typedef struct _VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY {
+  UINTN                                      Signature;
+  EFI_KEY_DATA                               KeyData;
+  EFI_KEY_NOTIFY_FUNCTION                    KeyNotificationFn;
+  LIST_ENTRY                                 NotifyEntry;
+} VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY;
+
+typedef struct {
+  UINTN                                      Front;
+  UINTN                                      Rear;
+  EFI_KEY_DATA                               Buffer[QUEUE_MAX_COUNT];
+} SIMPLE_QUEUE;
+
+typedef struct {
+  UINT8                                      Buffer[KEYBOARD_SCAN_CODE_MAX_COUNT];
+  UINTN                                      Head;
+  UINTN                                      Tail;
+} SCAN_CODE_QUEUE;
+
+typedef struct {
+  UINTN                                      Signature;
+  EFI_HANDLE                                 Handle;
+  PLATFORM_VIRTUAL_KBD_PROTOCOL              *PlatformVirtual;
+  EFI_SIMPLE_TEXT_INPUT_PROTOCOL             SimpleTextIn;
+  EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL          SimpleTextInputEx;
+
+  //
+  // Buffer storing EFI_KEY_DATA
+  //
+  SIMPLE_QUEUE                               Queue;
+  SIMPLE_QUEUE                               QueueForNotify;
+
+  //
+  // Notification Function List
+  //
+  LIST_ENTRY                                 NotifyList;
+  EFI_EVENT                                  KeyNotifyProcessEvent;
+  EFI_EVENT                                  TimerEvent;
+} VIRTUAL_KEYBOARD_DEV;
+
+#define VIRTUAL_KEYBOARD_DEV_FROM_THIS(a)  CR (a, VIRTUAL_KEYBOARD_DEV, SimpleTextIn, VIRTUAL_KEYBOARD_DEV_SIGNATURE)
+#define TEXT_INPUT_EX_VIRTUAL_KEYBOARD_DEV_FROM_THIS(a) \
+  CR (a, \
+      VIRTUAL_KEYBOARD_DEV, \
+      SimpleTextInputEx, \
+      VIRTUAL_KEYBOARD_DEV_SIGNATURE \
+      )
+
+//
+// Global Variables
+//
+extern EFI_DRIVER_BINDING_PROTOCOL   gVirtualKeyboardDriverBinding;
+
+//
+// Driver Binding Protocol functions
+//
+
+/**
+  Check whether the driver supports this device.
+
+  @param  This                   The Udriver binding protocol.
+  @param  Controller             The controller handle to check.
+  @param  RemainingDevicePath    The remaining device path.
+
+  @retval EFI_SUCCESS            The driver supports this controller.
+  @retval other                  This device isn't supported.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardDriverBindingSupported (
+  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
+  IN EFI_HANDLE                   Controller,
+  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
+  );
+
+/**
+  Starts the device with this driver.
+
+  @param  This                   The driver binding instance.
+  @param  Controller             Handle of device to bind driver to.
+  @param  RemainingDevicePath    Optional parameter use to pick a specific child
+                                 device to start.
+
+  @retval EFI_SUCCESS            The controller is controlled by the driver.
+  @retval Other                  This controller cannot be started.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardDriverBindingStart (
+  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
+  IN EFI_HANDLE                   Controller,
+  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
+  );
+
+/**
+  Stop the device handled by this driver.
+
+  @param  This                   The driver binding protocol.
+  @param  Controller             The controller to release.
+  @param  NumberOfChildren       The number of handles in ChildHandleBuffer.
+  @param  ChildHandleBuffer      The array of child handle.
+
+  @retval EFI_SUCCESS            The device was stopped.
+  @retval EFI_DEVICE_ERROR       The device could not be stopped due to a device error.
+  @retval Others                 Fail to uninstall protocols attached on the device.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardDriverBindingStop (
+  IN  EFI_DRIVER_BINDING_PROTOCOL  *This,
+  IN  EFI_HANDLE                   Controller,
+  IN  UINTN                        NumberOfChildren,
+  IN  EFI_HANDLE                   *ChildHandleBuffer
+  );
+
+/**
+  Retrieves a Unicode string that is the user readable name of the driver.
+
+  This function retrieves the user readable name of a driver in the form of a
+  Unicode string. If the driver specified by This has a user readable name in
+  the language specified by Language, then a pointer to the driver name is
+  returned in DriverName, and EFI_SUCCESS is returned. If the driver specified
+  by This does not support the language specified by Language,
+  then EFI_UNSUPPORTED is returned.
+
+  @param  This[in]              A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
+                                EFI_COMPONENT_NAME_PROTOCOL instance.
+
+  @param  Language[in]          A pointer to a Null-terminated ASCII string
+                                array indicating the language. This is the
+                                language of the driver name that the caller is
+                                requesting, and it must match one of the
+                                languages specified in SupportedLanguages. The
+                                number of languages supported by a driver is up
+                                to the driver writer. Language is specified
+                                in RFC 4646 or ISO 639-2 language code format.
+
+  @param  DriverName[out]       A pointer to the Unicode string to return.
+                                This Unicode string is the name of the
+                                driver specified by This in the language
+                                specified by Language.
+
+  @retval EFI_SUCCESS           The Unicode string for the Driver specified by
+                                This and the language specified by Language was
+                                returned in DriverName.
+
+  @retval EFI_INVALID_PAVIRTUALETER Language is NULL.
+
+  @retval EFI_INVALID_PAVIRTUALETER DriverName is NULL.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This does not support
+                                the language specified by Language.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardComponentNameGetDriverName (
+  IN  EFI_COMPONENT_NAME_PROTOCOL  *This,
+  IN  CHAR8                        *Language,
+  OUT CHAR16                       **DriverName
+  );
+
+
+/**
+  Retrieves a Unicode string that is the user readable name of the controller
+  that is being managed by a driver.
+
+  This function retrieves the user readable name of the controller specified by
+  ControllerHandle and ChildHandle in the form of a Unicode string. If the
+  driver specified by This has a user readable name in the language specified by
+  Language, then a pointer to the controller name is returned in ControllerName,
+  and EFI_SUCCESS is returned.  If the driver specified by This is not currently
+  managing the controller specified by ControllerHandle and ChildHandle,
+  then EFI_UNSUPPORTED is returned.  If the driver specified by This does not
+  support the language specified by Language, then EFI_UNSUPPORTED is returned.
+
+  @param  This[in]              A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
+                                EFI_COMPONENT_NAME_PROTOCOL instance.
+
+  @param  ControllerHandle[in]  The handle of a controller that the driver
+                                specified by This is managing.  This handle
+                                specifies the controller whose name is to be
+                                returned.
+
+  @param  ChildHandle[in]       The handle of the child controller to retrieve
+                                the name of.  This is an optional parameter that
+                                may be NULL.  It will be NULL for device
+                                drivers.  It will also be NULL for a bus drivers
+                                that wish to retrieve the name of the bus
+                                controller.  It will not be NULL for a bus
+                                driver that wishes to retrieve the name of a
+                                child controller.
+
+  @param  Language[in]          A pointer to a Null-terminated ASCII string
+                                array indicating the language.  This is the
+                                language of the driver name that the caller is
+                                requesting, and it must match one of the
+                                languages specified in SupportedLanguages. The
+                                number of languages supported by a driver is up
+                                to the driver writer. Language is specified in
+                                RFC 4646 or ISO 639-2 language code format.
+
+  @param  ControllerName[out]   A pointer to the Unicode string to return.
+                                This Unicode string is the name of the
+                                controller specified by ControllerHandle and
+                                ChildHandle in the language specified by
+                                Language from the point of view of the driver
+                                specified by This.
+
+  @retval EFI_SUCCESS           The Unicode string for the user readable name in
+                                the language specified by Language for the
+                                driver specified by This was returned in
+                                DriverName.
+
+  @retval EFI_INVALID_PAVIRTUALETER ControllerHandle is NULL.
+
+  @retval EFI_INVALID_PAVIRTUALETER ChildHandle is not NULL and it is not a valid
+                                EFI_HANDLE.
+
+  @retval EFI_INVALID_PAVIRTUALETER Language is NULL.
+
+  @retval EFI_INVALID_PAVIRTUALETER ControllerName is NULL.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This is not currently
+                                managing the controller specified by
+                                ControllerHandle and ChildHandle.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This does not support
+                                the language specified by Language.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardComponentNameGetControllerName (
+  IN  EFI_COMPONENT_NAME_PROTOCOL      *This,
+  IN  EFI_HANDLE                       ControllerHandle,
+  IN  EFI_HANDLE                       ChildHandle        OPTIONAL,
+  IN  CHAR8                            *Language,
+  OUT CHAR16                           **ControllerName
+  );
+
+
+//
+// Simple Text Input Protocol functions
+//
+/**
+  Reset the Keyboard and do BAT test for it, if (ExtendedVerification == TRUE) then do some extra keyboard validations.
+
+  @param  This                  Pointer of simple text Protocol.
+  @param  ExtendedVerification  Whether perform the extra validation of keyboard. True: perform; FALSE: skip.
+
+  @retval EFI_SUCCESS           The command byte is written successfully.
+  @retval EFI_DEVICE_ERROR      Errors occurred during resetting keyboard.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardReset (
+  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This,
+  IN  BOOLEAN                         ExtendedVerification
+  );
+
+/**
+  Reset the input device and optionaly run diagnostics
+
+  @param  This                  Protocol instance pointer.
+  @param  ExtendedVerification  Driver may perform diagnostics on reset.
+
+  @retval EFI_SUCCESS           The device was reset.
+  @retval EFI_DEVICE_ERROR      The device is not functioning properly and could
+                                not be reset.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardResetEx (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
+  IN BOOLEAN                            ExtendedVerification
+  );
+
+/**
+  Set certain state for the input device.
+
+  @param  This              Protocol instance pointer.
+  @param  KeyToggleState    A pointer to the EFI_KEY_TOGGLE_STATE to set the
+                            state for the input device.
+
+  @retval EFI_SUCCESS           The device state was set successfully.
+  @retval EFI_DEVICE_ERROR      The device is not functioning correctly and could
+                                not have the setting adjusted.
+  @retval EFI_UNSUPPORTED       The device does not have the ability to set its state.
+  @retval EFI_INVALID_PAVIRTUALETER KeyToggleState is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardSetState (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
+  IN EFI_KEY_TOGGLE_STATE               *KeyToggleState
+  );
+
+/**
+  Register a notification function for a particular keystroke for the input device.
+
+  @param  This                    Protocol instance pointer.
+  @param  KeyData                 A pointer to a buffer that is filled in with the keystroke
+                                  information data for the key that was pressed.
+  @param  KeyNotificationFunction Points to the function to be called when the key
+                                  sequence is typed specified by KeyData.
+  @param  NotifyHandle            Points to the unique handle assigned to the registered notification.
+
+
+  @retval EFI_SUCCESS             The notification function was registered successfully.
+  @retval EFI_OUT_OF_RESOURCES    Unable to allocate resources for necesssary data structures.
+  @retval EFI_INVALID_PAVIRTUALETER   KeyData or NotifyHandle is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardRegisterKeyNotify (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
+  IN EFI_KEY_DATA                       *KeyData,
+  IN EFI_KEY_NOTIFY_FUNCTION            KeyNotificationFunction,
+  OUT VOID                              **NotifyHandle
+  );
+
+/**
+  Remove a registered notification function from a particular keystroke.
+
+  @param  This                 Protocol instance pointer.
+  @param  NotificationHandle   The handle of the notification function being unregistered.
+
+  @retval EFI_SUCCESS             The notification function was unregistered successfully.
+  @retval EFI_INVALID_PAVIRTUALETER   The NotificationHandle is invalid.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardUnregisterKeyNotify (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
+  IN VOID                               *NotificationHandle
+  );
+
+//
+// Private worker functions
+//
+/**
+  Free keyboard notify list.
+
+  @param  ListHead   The list head
+
+  @retval EFI_SUCCESS           Free the notify list successfully
+  @retval EFI_INVALID_PAVIRTUALETER ListHead is invalid.
+
+**/
+EFI_STATUS
+VirtualKeyboardFreeNotifyList (
+  IN OUT LIST_ENTRY           *ListHead
+  );
+
+/**
+  Check if key is registered.
+
+  @param  RegsiteredData    A pointer to a buffer that is filled in with the keystroke
+                            state data for the key that was registered.
+  @param  InputData         A pointer to a buffer that is filled in with the keystroke
+                            state data for the key that was pressed.
+
+  @retval TRUE              Key be pressed matches a registered key.
+  @retval FLASE             Match failed.
+
+**/
+BOOLEAN
+IsKeyRegistered (
+  IN EFI_KEY_DATA  *RegsiteredData,
+  IN EFI_KEY_DATA  *InputData
+  );
+
+/**
+  Waiting on the keyboard event, if there's any key pressed by the user, signal the event
+
+  @param  Event       The event that be siganlled when any key has been stroked.
+  @param  Context     Pointer of the protocol EFI_SIMPLE_TEXT_INPUT_PROTOCOL.
+
+**/
+VOID
+EFIAPI
+VirtualKeyboardWaitForKey (
+  IN  EFI_EVENT  Event,
+  IN  VOID       *Context
+  );
+
+/**
+  Waiting on the keyboard event, if there's any key pressed by the user, signal the event
+
+  @param  Event    The event that be siganlled when any key has been stroked.
+  @param  Context  Pointer of the protocol EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL.
+
+**/
+VOID
+EFIAPI
+VirtualKeyboardWaitForKeyEx (
+  IN  EFI_EVENT  Event,
+  IN  VOID       *Context
+  );
+
+/**
+  Timer event handler: read a series of key stroke from 8042
+  and put them into memory key buffer.
+  It is registered as running under TPL_NOTIFY
+
+  @param  Event   The timer event
+  @param  Context A VIRTUAL_KEYBOARD_DEV pointer
+
+**/
+VOID
+EFIAPI
+VirtualKeyboardTimerHandler (
+  IN EFI_EVENT    Event,
+  IN VOID         *Context
+  );
+
+/**
+  Process key notify.
+
+  @param  Event                 Indicates the event that invoke this function.
+  @param  Context               Indicates the calling context.
+**/
+VOID
+EFIAPI
+KeyNotifyProcessHandler (
+  IN  EFI_EVENT                 Event,
+  IN  VOID                      *Context
+  );
+
+/**
+  Read out the scan code of the key that has just been stroked.
+
+  @param  This        Pointer of simple text Protocol.
+  @param  Key         Pointer for store the key that read out.
+
+  @retval EFI_SUCCESS The key is read out successfully.
+  @retval other       The key reading failed.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardReadKeyStroke (
+  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This,
+  OUT EFI_INPUT_KEY                   *Key
+  );
+
+/**
+  Reads the next keystroke from the input device. The WaitForKey Event can
+  be used to test for existance of a keystroke via WaitForEvent () call.
+
+  @param  This         Protocol instance pointer.
+  @param  KeyData      A pointer to a buffer that is filled in with the keystroke
+                       state data for the key that was pressed.
+
+  @retval  EFI_SUCCESS           The keystroke information was returned.
+  @retval  EFI_NOT_READY         There was no keystroke data availiable.
+  @retval  EFI_DEVICE_ERROR      The keystroke information was not returned due to
+                                 hardware errors.
+  @retval  EFI_INVALID_PAVIRTUALETER KeyData is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardReadKeyStrokeEx (
+  IN  EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL *This,
+  OUT EFI_KEY_DATA                      *KeyData
+  );
+
+#endif /* _VIRTUAL_KEYBOARD_H_ */
diff --git a/EmbeddedPkg/Include/Protocol/PlatformVirtualKeyboard.h b/EmbeddedPkg/Include/Protocol/PlatformVirtualKeyboard.h
new file mode 100644
index 000000000000..c64d21e45c08
--- /dev/null
+++ b/EmbeddedPkg/Include/Protocol/PlatformVirtualKeyboard.h
@@ -0,0 +1,65 @@ 
+/** @file
+
+  Copyright (c) 2018, Linaro. 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.
+
+**/
+
+#ifndef __PLATFORM_VIRTUAL_KEYBOARD_H__
+#define __PLATFORM_VIRTUAL_KEYBOARD_H__
+
+//
+// Protocol interface structure
+//
+typedef struct _PLATFORM_VIRTUAL_KBD_PROTOCOL  PLATFORM_VIRTUAL_KBD_PROTOCOL;
+
+typedef struct _VIRTUAL_KBD_KEY                VIRTUAL_KBD_KEY;
+
+#define VIRTUAL_KEYBOARD_KEY_SIGNATURE         SIGNATURE_32 ('v', 'k', 'b', 'd')
+
+struct _VIRTUAL_KBD_KEY {
+  UINTN                    Signature;
+  EFI_INPUT_KEY            Key;
+};
+
+typedef
+EFI_STATUS
+(EFIAPI *PLATFORM_VIRTUAL_KBD_REGISTER) (
+  IN VOID
+  );
+
+typedef
+EFI_STATUS
+(EFIAPI *PLATFORM_VIRTUAL_KBD_RESET) (
+  IN VOID
+  );
+
+typedef
+BOOLEAN
+(EFIAPI *PLATFORM_VIRTUAL_KBD_QUERY) (
+  IN VIRTUAL_KBD_KEY                           *VirtualKey
+  );
+
+typedef
+EFI_STATUS
+(EFIAPI *PLATFORM_VIRTUAL_KBD_CLEAR) (
+  IN VIRTUAL_KBD_KEY                           *VirtualKey
+  );
+
+struct _PLATFORM_VIRTUAL_KBD_PROTOCOL {
+  PLATFORM_VIRTUAL_KBD_REGISTER                Register;
+  PLATFORM_VIRTUAL_KBD_RESET                   Reset;
+  PLATFORM_VIRTUAL_KBD_QUERY                   Query;
+  PLATFORM_VIRTUAL_KBD_CLEAR                   Clear;
+};
+
+extern EFI_GUID gPlatformVirtualKeyboardProtocolGuid;
+
+#endif /* __PLATFORM_VIRTUAL_KEYBOARD_H__ */
diff --git a/EmbeddedPkg/Drivers/VirtualKeyboardDxe/ComponentName.c b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/ComponentName.c
new file mode 100644
index 000000000000..9ba706c37b8d
--- /dev/null
+++ b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/ComponentName.c
@@ -0,0 +1,188 @@ 
+/** @file
+
+Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
+
+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 "VirtualKeyboard.h"
+
+//
+// EFI Component Name Protocol
+//
+GLOBAL_REMOVE_IF_UNREFERENCED EFI_COMPONENT_NAME_PROTOCOL  gVirtualKeyboardComponentName = {
+  VirtualKeyboardComponentNameGetDriverName,
+  VirtualKeyboardComponentNameGetControllerName,
+  "eng"
+};
+
+//
+// EFI Component Name 2 Protocol
+//
+GLOBAL_REMOVE_IF_UNREFERENCED EFI_COMPONENT_NAME2_PROTOCOL gVirtualKeyboardComponentName2 = {
+  (EFI_COMPONENT_NAME2_GET_DRIVER_NAME) VirtualKeyboardComponentNameGetDriverName,
+  (EFI_COMPONENT_NAME2_GET_CONTROLLER_NAME) VirtualKeyboardComponentNameGetControllerName,
+  "en"
+};
+
+
+GLOBAL_REMOVE_IF_UNREFERENCED EFI_UNICODE_STRING_TABLE mVirtualKeyboardDriverNameTable[] = {
+  {
+    "eng;en",
+    L"Virtual Keyboard Driver"
+  },
+  {
+    "zh-CHS",
+    L"虚拟键盘驱动程序"
+  },
+  {
+    NULL,
+    NULL
+  }
+};
+
+/**
+  Retrieves a Unicode string that is the user readable name of the driver.
+
+  This function retrieves the user readable name of a driver in the form of a
+  Unicode string. If the driver specified by This has a user readable name in
+  the language specified by Language, then a pointer to the driver name is
+  returned in DriverName, and EFI_SUCCESS is returned. If the driver specified
+  by This does not support the language specified by Language,
+  then EFI_UNSUPPORTED is returned.
+
+  @param  This[in]              A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
+                                EFI_COMPONENT_NAME_PROTOCOL instance.
+
+  @param  Language[in]          A pointer to a Null-terminated ASCII string
+                                array indicating the language. This is the
+                                language of the driver name that the caller is
+                                requesting, and it must match one of the
+                                languages specified in SupportedLanguages. The
+                                number of languages supported by a driver is up
+                                to the driver writer. Language is specified
+                                in RFC 4646 or ISO 639-2 language code format.
+
+  @param  DriverName[out]       A pointer to the Unicode string to return.
+                                This Unicode string is the name of the
+                                driver specified by This in the language
+                                specified by Language.
+
+  @retval EFI_SUCCESS           The Unicode string for the Driver specified by
+                                This and the language specified by Language was
+                                returned in DriverName.
+
+  @retval EFI_INVALID_PARAMETER Language is NULL.
+
+  @retval EFI_INVALID_PARAMETER DriverName is NULL.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This does not support
+                                the language specified by Language.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardComponentNameGetDriverName (
+  IN  EFI_COMPONENT_NAME_PROTOCOL  *This,
+  IN  CHAR8                        *Language,
+  OUT CHAR16                       **DriverName
+  )
+{
+  return LookupUnicodeString2 (
+           Language,
+           This->SupportedLanguages,
+           mVirtualKeyboardDriverNameTable,
+           DriverName,
+           (BOOLEAN)(This == &gVirtualKeyboardComponentName)
+           );
+}
+
+/**
+  Retrieves a Unicode string that is the user readable name of the controller
+  that is being managed by a driver.
+
+  This function retrieves the user readable name of the controller specified by
+  ControllerHandle and ChildHandle in the form of a Unicode string. If the
+  driver specified by This has a user readable name in the language specified by
+  Language, then a pointer to the controller name is returned in ControllerName,
+  and EFI_SUCCESS is returned.  If the driver specified by This is not currently
+  managing the controller specified by ControllerHandle and ChildHandle,
+  then EFI_UNSUPPORTED is returned.  If the driver specified by This does not
+  support the language specified by Language, then EFI_UNSUPPORTED is returned.
+
+  @param  This[in]              A pointer to the EFI_COMPONENT_NAME2_PROTOCOL or
+                                EFI_COMPONENT_NAME_PROTOCOL instance.
+
+  @param  ControllerHandle[in]  The handle of a controller that the driver
+                                specified by This is managing.  This handle
+                                specifies the controller whose name is to be
+                                returned.
+
+  @param  ChildHandle[in]       The handle of the child controller to retrieve
+                                the name of.  This is an optional parameter that
+                                may be NULL.  It will be NULL for device
+                                drivers.  It will also be NULL for a bus drivers
+                                that wish to retrieve the name of the bus
+                                controller.  It will not be NULL for a bus
+                                driver that wishes to retrieve the name of a
+                                child controller.
+
+  @param  Language[in]          A pointer to a Null-terminated ASCII string
+                                array indicating the language.  This is the
+                                language of the driver name that the caller is
+                                requesting, and it must match one of the
+                                languages specified in SupportedLanguages. The
+                                number of languages supported by a driver is up
+                                to the driver writer. Language is specified in
+                                RFC 4646 or ISO 639-2 language code format.
+
+  @param  ControllerName[out]   A pointer to the Unicode string to return.
+                                This Unicode string is the name of the
+                                controller specified by ControllerHandle and
+                                ChildHandle in the language specified by
+                                Language from the point of view of the driver
+                                specified by This.
+
+  @retval EFI_SUCCESS           The Unicode string for the user readable name in
+                                the language specified by Language for the
+                                driver specified by This was returned in
+                                DriverName.
+
+  @retval EFI_INVALID_PARAMETER ControllerHandle is NULL.
+
+  @retval EFI_INVALID_PARAMETER ChildHandle is not NULL and it is not a valid
+                                EFI_HANDLE.
+
+  @retval EFI_INVALID_PARAMETER Language is NULL.
+
+  @retval EFI_INVALID_PARAMETER ControllerName is NULL.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This is not currently
+                                managing the controller specified by
+                                ControllerHandle and ChildHandle.
+
+  @retval EFI_UNSUPPORTED       The driver specified by This does not support
+                                the language specified by Language.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardComponentNameGetControllerName (
+  IN  EFI_COMPONENT_NAME_PROTOCOL                     *This,
+  IN  EFI_HANDLE                                      ControllerHandle,
+  IN  EFI_HANDLE                                      ChildHandle        OPTIONAL,
+  IN  CHAR8                                           *Language,
+  OUT CHAR16                                          **ControllerName
+  )
+{
+  return EFI_UNSUPPORTED;
+}
diff --git a/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboard.c b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboard.c
new file mode 100644
index 000000000000..6609bc8dbe9b
--- /dev/null
+++ b/EmbeddedPkg/Drivers/VirtualKeyboardDxe/VirtualKeyboard.c
@@ -0,0 +1,1149 @@ 
+/** @file
+  VirtualKeyboard driver
+
+Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2018, Linaro Ltd. All rights reserved.<BR>
+
+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 "VirtualKeyboard.h"
+
+//
+// RAM Keyboard Driver Binding Protocol Instance
+//
+EFI_DRIVER_BINDING_PROTOCOL gVirtualKeyboardDriverBinding = {
+  VirtualKeyboardDriverBindingSupported,
+  VirtualKeyboardDriverBindingStart,
+  VirtualKeyboardDriverBindingStop,
+  0x10,
+  NULL,
+  NULL
+};
+
+//
+// EFI Driver Binding Protocol Functions
+//
+
+/**
+  Check whether the driver supports this device.
+
+  @param  This                   The Udriver binding protocol.
+  @param  Controller             The controller handle to check.
+  @param  RemainingDevicePath    The remaining device path.
+
+  @retval EFI_SUCCESS            The driver supports this controller.
+  @retval other                  This device isn't supported.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardDriverBindingSupported (
+  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
+  IN EFI_HANDLE                   Controller,
+  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
+  )
+{
+  EFI_STATUS                      Status;
+  PLATFORM_VIRTUAL_KBD_PROTOCOL   *PlatformVirtual;
+
+  Status = gBS->OpenProtocol (
+                  Controller,
+                  &gPlatformVirtualKeyboardProtocolGuid,
+                  (VOID **) &PlatformVirtual,
+                  This->DriverBindingHandle,
+                  Controller,
+                  EFI_OPEN_PROTOCOL_BY_DRIVER
+                  );
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+  gBS->CloseProtocol (
+         Controller,
+         &gPlatformVirtualKeyboardProtocolGuid,
+         This->DriverBindingHandle,
+         Controller
+         );
+  return Status;
+}
+
+/**
+  Starts the device with this driver.
+
+  @param  This                   The driver binding instance.
+  @param  Controller             Handle of device to bind driver to.
+  @param  RemainingDevicePath    Optional parameter use to pick a specific child
+                                 device to start.
+
+  @retval EFI_SUCCESS            The controller is controlled by the driver.
+  @retval Other                  This controller cannot be started.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardDriverBindingStart (
+  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
+  IN EFI_HANDLE                   Controller,
+  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
+  )
+{
+  EFI_STATUS                                Status;
+  VIRTUAL_KEYBOARD_DEV                      *VirtualKeyboardPrivate;
+  PLATFORM_VIRTUAL_KBD_PROTOCOL             *PlatformVirtual;
+
+  Status = gBS->OpenProtocol (
+                  Controller,
+                  &gPlatformVirtualKeyboardProtocolGuid,
+                  (VOID **) &PlatformVirtual,
+                  This->DriverBindingHandle,
+                  Controller,
+                  EFI_OPEN_PROTOCOL_BY_DRIVER
+                  );
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  //
+  // Allocate the private device structure
+  //
+  VirtualKeyboardPrivate = (VIRTUAL_KEYBOARD_DEV *) AllocateZeroPool (sizeof (VIRTUAL_KEYBOARD_DEV));
+  if (VirtualKeyboardPrivate == NULL) {
+    Status = EFI_OUT_OF_RESOURCES;
+    goto Done;
+  }
+
+  //
+  // Initialize the private device structure
+  //
+  VirtualKeyboardPrivate->Signature                  = VIRTUAL_KEYBOARD_DEV_SIGNATURE;
+  VirtualKeyboardPrivate->Handle                     = Controller;
+  VirtualKeyboardPrivate->PlatformVirtual            = PlatformVirtual;
+  VirtualKeyboardPrivate->Queue.Front                = 0;
+  VirtualKeyboardPrivate->Queue.Rear                 = 0;
+  VirtualKeyboardPrivate->QueueForNotify.Front       = 0;
+  VirtualKeyboardPrivate->QueueForNotify.Rear        = 0;
+
+  VirtualKeyboardPrivate->SimpleTextIn.Reset         = VirtualKeyboardReset;
+  VirtualKeyboardPrivate->SimpleTextIn.ReadKeyStroke = VirtualKeyboardReadKeyStroke;
+
+  VirtualKeyboardPrivate->SimpleTextInputEx.Reset               = VirtualKeyboardResetEx;
+  VirtualKeyboardPrivate->SimpleTextInputEx.ReadKeyStrokeEx     = VirtualKeyboardReadKeyStrokeEx;
+  VirtualKeyboardPrivate->SimpleTextInputEx.SetState            = VirtualKeyboardSetState;
+
+  VirtualKeyboardPrivate->SimpleTextInputEx.RegisterKeyNotify   = VirtualKeyboardRegisterKeyNotify;
+  VirtualKeyboardPrivate->SimpleTextInputEx.UnregisterKeyNotify = VirtualKeyboardUnregisterKeyNotify;
+  InitializeListHead (&VirtualKeyboardPrivate->NotifyList);
+
+  Status = PlatformVirtual->Register ();
+  if (EFI_ERROR (Status)) {
+    goto Done;
+  }
+
+  //
+  // Report that the keyboard is being enabled
+  //
+  REPORT_STATUS_CODE (
+    EFI_PROGRESS_CODE,
+    EFI_PERIPHERAL_KEYBOARD | EFI_P_PC_ENABLE
+    );
+
+  //
+  // Setup the WaitForKey event
+  //
+  Status = gBS->CreateEvent (
+                  EVT_NOTIFY_WAIT,
+                  TPL_NOTIFY,
+                  VirtualKeyboardWaitForKey,
+                  &(VirtualKeyboardPrivate->SimpleTextIn),
+                  &((VirtualKeyboardPrivate->SimpleTextIn).WaitForKey)
+                  );
+  if (EFI_ERROR (Status)) {
+    (VirtualKeyboardPrivate->SimpleTextIn).WaitForKey = NULL;
+    goto Done;
+  }
+  Status = gBS->CreateEvent (
+                  EVT_NOTIFY_WAIT,
+                  TPL_NOTIFY,
+                  VirtualKeyboardWaitForKeyEx,
+                  &(VirtualKeyboardPrivate->SimpleTextInputEx),
+                  &(VirtualKeyboardPrivate->SimpleTextInputEx.WaitForKeyEx)
+                  );
+  if (EFI_ERROR (Status)) {
+    VirtualKeyboardPrivate->SimpleTextInputEx.WaitForKeyEx = NULL;
+    goto Done;
+  }
+
+  //
+  // Setup a periodic timer, used for reading keystrokes at a fixed interval
+  //
+  Status = gBS->CreateEvent (
+                  EVT_TIMER | EVT_NOTIFY_SIGNAL,
+                  TPL_NOTIFY,
+                  VirtualKeyboardTimerHandler,
+                  VirtualKeyboardPrivate,
+                  &VirtualKeyboardPrivate->TimerEvent
+                  );
+  if (EFI_ERROR (Status)) {
+    Status = EFI_OUT_OF_RESOURCES;
+    goto Done;
+  }
+
+  Status = gBS->SetTimer (
+                  VirtualKeyboardPrivate->TimerEvent,
+                  TimerPeriodic,
+                  KEYBOARD_TIMER_INTERVAL
+                  );
+  if (EFI_ERROR (Status)) {
+    Status = EFI_OUT_OF_RESOURCES;
+    goto Done;
+  }
+
+  Status = gBS->CreateEvent (
+                  EVT_NOTIFY_SIGNAL,
+                  TPL_CALLBACK,
+                  KeyNotifyProcessHandler,
+                  VirtualKeyboardPrivate,
+                  &VirtualKeyboardPrivate->KeyNotifyProcessEvent
+                  );
+  if (EFI_ERROR (Status)) {
+    Status = EFI_OUT_OF_RESOURCES;
+    goto Done;
+  }
+
+  //
+  // Reset the keyboard device
+  //
+  Status = VirtualKeyboardPrivate->SimpleTextInputEx.Reset (
+                                     &VirtualKeyboardPrivate->SimpleTextInputEx,
+                                     FALSE
+                                     );
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "[KBD]Reset Failed. Status - %r\n", Status));
+    goto Done;
+  }
+  //
+  // Install protocol interfaces for the keyboard device.
+  //
+  Status = gBS->InstallMultipleProtocolInterfaces (
+                  &Controller,
+                  &gEfiSimpleTextInProtocolGuid,
+                  &VirtualKeyboardPrivate->SimpleTextIn,
+                  &gEfiSimpleTextInputExProtocolGuid,
+                  &VirtualKeyboardPrivate->SimpleTextInputEx,
+                  NULL
+                  );
+
+Done:
+  if (EFI_ERROR (Status)) {
+    if (VirtualKeyboardPrivate != NULL) {
+      if ((VirtualKeyboardPrivate->SimpleTextIn).WaitForKey != NULL) {
+        gBS->CloseEvent ((VirtualKeyboardPrivate->SimpleTextIn).WaitForKey);
+      }
+
+      if ((VirtualKeyboardPrivate->SimpleTextInputEx).WaitForKeyEx != NULL) {
+        gBS->CloseEvent (
+               (VirtualKeyboardPrivate->SimpleTextInputEx).WaitForKeyEx
+               );
+      }
+
+      if (VirtualKeyboardPrivate->KeyNotifyProcessEvent != NULL) {
+        gBS->CloseEvent (VirtualKeyboardPrivate->KeyNotifyProcessEvent);
+      }
+
+      VirtualKeyboardFreeNotifyList (&VirtualKeyboardPrivate->NotifyList);
+
+      if (VirtualKeyboardPrivate->TimerEvent != NULL) {
+        gBS->CloseEvent (VirtualKeyboardPrivate->TimerEvent);
+      }
+      FreePool (VirtualKeyboardPrivate);
+    }
+  }
+
+  gBS->CloseProtocol (
+         Controller,
+         &gPlatformVirtualKeyboardProtocolGuid,
+         This->DriverBindingHandle,
+         Controller
+         );
+
+  return Status;
+}
+
+/**
+  Stop the device handled by this driver.
+
+  @param  This                   The driver binding protocol.
+  @param  Controller             The controller to release.
+  @param  NumberOfChildren       The number of handles in ChildHandleBuffer.
+  @param  ChildHandleBuffer      The array of child handle.
+
+  @retval EFI_SUCCESS            The device was stopped.
+  @retval EFI_DEVICE_ERROR       The device could not be stopped due to a
+                                 device error.
+  @retval Others                 Fail to uninstall protocols attached on the
+                                 device.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardDriverBindingStop (
+  IN  EFI_DRIVER_BINDING_PROTOCOL  *This,
+  IN  EFI_HANDLE                   Controller,
+  IN  UINTN                        NumberOfChildren,
+  IN  EFI_HANDLE                   *ChildHandleBuffer
+  )
+{
+  return EFI_SUCCESS;
+}
+
+
+/**
+  Enqueue the key.
+
+  @param  Queue                 The queue to be enqueued.
+  @param  KeyData               The key data to be enqueued.
+
+  @retval EFI_NOT_READY         The queue is full.
+  @retval EFI_SUCCESS           Successfully enqueued the key data.
+
+**/
+EFI_STATUS
+Enqueue (
+  IN SIMPLE_QUEUE         *Queue,
+  IN EFI_KEY_DATA         *KeyData
+  )
+{
+  if ((Queue->Rear + 1) % QUEUE_MAX_COUNT == Queue->Front) {
+    return EFI_NOT_READY;
+  }
+
+  CopyMem (&Queue->Buffer[Queue->Rear], KeyData, sizeof (EFI_KEY_DATA));
+  Queue->Rear = (Queue->Rear + 1) % QUEUE_MAX_COUNT;
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Dequeue the key.
+
+  @param  Queue                 The queue to be dequeued.
+  @param  KeyData               The key data to be dequeued.
+
+  @retval EFI_NOT_READY         The queue is empty.
+  @retval EFI_SUCCESS           Successfully dequeued the key data.
+
+**/
+EFI_STATUS
+Dequeue (
+  IN SIMPLE_QUEUE         *Queue,
+  IN EFI_KEY_DATA         *KeyData
+  )
+{
+  if (Queue->Front == Queue->Rear) {
+    return EFI_NOT_READY;
+  }
+
+  CopyMem (KeyData, &Queue->Buffer[Queue->Front], sizeof (EFI_KEY_DATA));
+  Queue->Front  = (Queue->Front + 1) % QUEUE_MAX_COUNT;
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Check whether the queue is empty.
+
+  @param  Queue                 The queue to be checked.
+
+  @retval EFI_NOT_READY         The queue is empty.
+  @retval EFI_SUCCESS           The queue is not empty.
+
+**/
+EFI_STATUS
+CheckQueue (
+  IN SIMPLE_QUEUE         *Queue
+  )
+{
+  if (Queue->Front == Queue->Rear) {
+    return EFI_NOT_READY;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Check key buffer to get the key stroke status.
+
+  @param  This         Pointer of the protocol EFI_SIMPLE_TEXT_IN_PROTOCOL.
+
+  @retval EFI_SUCCESS  A key is being pressed now.
+  @retval Other        No key is now pressed.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardCheckForKey (
+  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This
+  )
+{
+  VIRTUAL_KEYBOARD_DEV     *VirtualKeyboardPrivate;
+
+  VirtualKeyboardPrivate = VIRTUAL_KEYBOARD_DEV_FROM_THIS (This);
+
+  return CheckQueue (&VirtualKeyboardPrivate->Queue);
+}
+
+/**
+  Free keyboard notify list.
+
+  @param  ListHead   The list head
+
+  @retval EFI_SUCCESS           Free the notify list successfully
+  @retval EFI_INVALID_PARAMETER ListHead is invalid.
+
+**/
+EFI_STATUS
+VirtualKeyboardFreeNotifyList (
+  IN OUT LIST_ENTRY           *ListHead
+  )
+{
+  VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY *NotifyNode;
+
+  if (ListHead == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+  while (!IsListEmpty (ListHead)) {
+    NotifyNode = CR (
+                   ListHead->ForwardLink,
+                   VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY,
+                   NotifyEntry,
+                   VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE
+                   );
+    RemoveEntryList (ListHead->ForwardLink);
+    gBS->FreePool (NotifyNode);
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Judge whether is a registed key
+
+  @param RegsiteredData       A pointer to a buffer that is filled in with
+                              the keystroke state data for the key that was
+                              registered.
+  @param InputData            A pointer to a buffer that is filled in with
+                              the keystroke state data for the key that was
+                              pressed.
+
+  @retval TRUE                Key be pressed matches a registered key.
+  @retval FLASE               Match failed.
+
+**/
+BOOLEAN
+IsKeyRegistered (
+  IN EFI_KEY_DATA  *RegsiteredData,
+  IN EFI_KEY_DATA  *InputData
+  )
+
+{
+  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;
+
+}
+
+/**
+  Event notification function for SIMPLE_TEXT_IN.WaitForKey event
+  Signal the event if there is key available
+
+  @param Event    the event object
+  @param Context  waitting context
+
+**/
+VOID
+EFIAPI
+VirtualKeyboardWaitForKey (
+  IN  EFI_EVENT               Event,
+  IN  VOID                    *Context
+  )
+{
+  //
+  // Stall 1ms to give a chance to let other driver interrupt this routine
+  // for their timer event.
+  // e.g. UI setup or Shell, other drivers which are driven by timer event
+  // will have a bad performance during this period,
+  // e.g. usb keyboard driver.
+  // Add a stall period can greatly increate other driver performance during
+  // the WaitForKey is recursivly invoked. 1ms delay will make little impact
+  // to the thunk keyboard driver, and user can not feel the delay at all when
+  // input.
+  //
+  gBS->Stall (1000);
+  //
+  // Use TimerEvent callback function to check whether there's any key pressed
+  //
+  VirtualKeyboardTimerHandler (NULL, VIRTUAL_KEYBOARD_DEV_FROM_THIS (Context));
+
+  if (!EFI_ERROR (VirtualKeyboardCheckForKey (Context))) {
+    gBS->SignalEvent (Event);
+  }
+}
+
+/**
+  Event notification function for SIMPLE_TEXT_INPUT_EX_PROTOCOL.WaitForKeyEx
+  event. Signal the event if there is key available
+
+  @param Event    event object
+  @param Context  waiting context
+
+**/
+VOID
+EFIAPI
+VirtualKeyboardWaitForKeyEx (
+  IN  EFI_EVENT               Event,
+  IN  VOID                    *Context
+  )
+
+{
+  VIRTUAL_KEYBOARD_DEV                     *VirtualKeyboardPrivate;
+
+  VirtualKeyboardPrivate = TEXT_INPUT_EX_VIRTUAL_KEYBOARD_DEV_FROM_THIS (Context);
+  VirtualKeyboardWaitForKey (Event, &VirtualKeyboardPrivate->SimpleTextIn);
+
+}
+
+//
+// EFI Simple Text In Protocol Functions
+//
+/**
+  Reset the Keyboard and do BAT test for it, if (ExtendedVerification == TRUE)
+  then do some extra keyboard validations.
+
+  @param  This                  Pointer of simple text Protocol.
+  @param  ExtendedVerification  Whether perform the extra validation of
+                                keyboard. True: perform; FALSE: skip.
+
+  @retval EFI_SUCCESS           The command byte is written successfully.
+  @retval EFI_DEVICE_ERROR      Errors occurred during resetting keyboard.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardReset (
+  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This,
+  IN  BOOLEAN                         ExtendedVerification
+  )
+{
+  VIRTUAL_KEYBOARD_DEV *VirtualKeyboardPrivate;
+  EFI_STATUS           Status;
+  EFI_TPL              OldTpl;
+
+  VirtualKeyboardPrivate = VIRTUAL_KEYBOARD_DEV_FROM_THIS (This);
+
+  //
+  // Raise TPL to avoid mouse operation impact
+  //
+  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
+
+  if (VirtualKeyboardPrivate->PlatformVirtual &&
+      VirtualKeyboardPrivate->PlatformVirtual->Reset) {
+    Status = VirtualKeyboardPrivate->PlatformVirtual->Reset ();
+  } else {
+    Status = EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // resume priority of task level
+  //
+  gBS->RestoreTPL (OldTpl);
+
+  return Status;
+}
+
+/**
+  Reset the input device and optionaly run diagnostics
+
+  @param  This                  Protocol instance pointer.
+  @param  ExtendedVerification  Driver may perform diagnostics on reset.
+
+  @retval EFI_SUCCESS           The device was reset.
+  @retval EFI_DEVICE_ERROR      The device is not functioning properly and
+                                could not be reset.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardResetEx (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
+  IN BOOLEAN                            ExtendedVerification
+  )
+{
+  VIRTUAL_KEYBOARD_DEV                  *VirtualKeyboardPrivate;
+  EFI_STATUS                            Status;
+  EFI_TPL                               OldTpl;
+
+  VirtualKeyboardPrivate = TEXT_INPUT_EX_VIRTUAL_KEYBOARD_DEV_FROM_THIS (This);
+
+  Status = VirtualKeyboardPrivate->SimpleTextIn.Reset (
+                                     &VirtualKeyboardPrivate->SimpleTextIn,
+                                     ExtendedVerification
+                                     );
+  if (EFI_ERROR (Status)) {
+    return EFI_DEVICE_ERROR;
+  }
+
+  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
+
+  gBS->RestoreTPL (OldTpl);
+
+  return EFI_SUCCESS;
+
+}
+
+/**
+  Reads the next keystroke from the input device. The WaitForKey Event can
+  be used to test for existance of a keystroke via WaitForEvent () call.
+
+  @param  VirtualKeyboardPrivate   Virtualkeyboard driver private structure.
+  @param  KeyData                  A pointer to a buffer that is filled in
+                                   with the keystroke state data for the key
+                                   that was pressed.
+
+  @retval EFI_SUCCESS              The keystroke information was returned.
+  @retval EFI_NOT_READY            There was no keystroke data availiable.
+  @retval EFI_DEVICE_ERROR         The keystroke information was not returned
+                                   due to hardware errors.
+  @retval EFI_INVALID_PARAMETER    KeyData is NULL.
+
+**/
+EFI_STATUS
+KeyboardReadKeyStrokeWorker (
+  IN VIRTUAL_KEYBOARD_DEV  *VirtualKeyboardPrivate,
+  OUT EFI_KEY_DATA      *KeyData
+  )
+{
+  EFI_STATUS                            Status;
+  EFI_TPL                               OldTpl;
+  if (KeyData == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Use TimerEvent callback function to check whether there's any key pressed
+  //
+
+  //
+  // Stall 1ms to give a chance to let other driver interrupt this routine for
+  // their timer event.
+  // e.g. OS loader, other drivers which are driven by timer event will have a
+  // bad performance during this period,
+  // e.g. usb keyboard driver.
+  // Add a stall period can greatly increate other driver performance during
+  // the WaitForKey is recursivly invoked. 1ms delay will make little impact
+  // to the thunk keyboard driver, and user can not feel the delay at all when
+  // input.
+  //
+  gBS->Stall (1000);
+
+  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
+
+  VirtualKeyboardTimerHandler (NULL, VirtualKeyboardPrivate);
+  //
+  // If there's no key, just return
+  //
+  Status = CheckQueue (&VirtualKeyboardPrivate->Queue);
+  if (EFI_ERROR (Status)) {
+    gBS->RestoreTPL (OldTpl);
+    return EFI_NOT_READY;
+  }
+
+  Status = Dequeue (&VirtualKeyboardPrivate->Queue, KeyData);
+
+  gBS->RestoreTPL (OldTpl);
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Read out the scan code of the key that has just been stroked.
+
+  @param  This        Pointer of simple text Protocol.
+  @param  Key         Pointer for store the key that read out.
+
+  @retval EFI_SUCCESS The key is read out successfully.
+  @retval other       The key reading failed.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardReadKeyStroke (
+  IN  EFI_SIMPLE_TEXT_INPUT_PROTOCOL  *This,
+  OUT EFI_INPUT_KEY                   *Key
+  )
+{
+  VIRTUAL_KEYBOARD_DEV     *VirtualKeyboardPrivate;
+  EFI_STATUS               Status;
+  EFI_KEY_DATA             KeyData;
+
+  VirtualKeyboardPrivate = VIRTUAL_KEYBOARD_DEV_FROM_THIS (This);
+
+  Status = KeyboardReadKeyStrokeWorker (VirtualKeyboardPrivate, &KeyData);
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  //
+  // Convert the Ctrl+[a-z] to Ctrl+[1-26]
+  //
+  if ((KeyData.KeyState.KeyShiftState & (EFI_LEFT_CONTROL_PRESSED | EFI_RIGHT_CONTROL_PRESSED)) != 0) {
+    if (KeyData.Key.UnicodeChar >= L'a' &&
+        KeyData.Key.UnicodeChar <= L'z') {
+      KeyData.Key.UnicodeChar = (CHAR16) (KeyData.Key.UnicodeChar - L'a' + 1);
+    } else if (KeyData.Key.UnicodeChar >= L'A' &&
+               KeyData.Key.UnicodeChar <= L'Z') {
+      KeyData.Key.UnicodeChar = (CHAR16) (KeyData.Key.UnicodeChar - L'A' + 1);
+    }
+  }
+
+  CopyMem (Key, &KeyData.Key, sizeof (EFI_INPUT_KEY));
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Reads the next keystroke from the input device. The WaitForKey Event can
+  be used to test for existance of a keystroke via WaitForEvent () call.
+
+  @param  This         Protocol instance pointer.
+  @param  KeyData      A pointer to a buffer that is filled in with the
+                       keystroke state data for the key that was pressed.
+
+  @retval  EFI_SUCCESS           The keystroke information was returned.
+  @retval  EFI_NOT_READY         There was no keystroke data availiable.
+  @retval  EFI_DEVICE_ERROR      The keystroke information was not returned
+                                 due to hardware errors.
+  @retval  EFI_INVALID_PARAMETER KeyData is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardReadKeyStrokeEx (
+  IN  EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL *This,
+  OUT EFI_KEY_DATA                      *KeyData
+  )
+{
+  VIRTUAL_KEYBOARD_DEV                  *VirtualKeyboardPrivate;
+
+  if (KeyData == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  VirtualKeyboardPrivate = TEXT_INPUT_EX_VIRTUAL_KEYBOARD_DEV_FROM_THIS (This);
+
+  return KeyboardReadKeyStrokeWorker (VirtualKeyboardPrivate, KeyData);
+
+}
+
+/**
+  Set certain state for the input device.
+
+  @param  This              Protocol instance pointer.
+  @param  KeyToggleState    A pointer to the EFI_KEY_TOGGLE_STATE to set the
+                            state for the input device.
+
+  @retval EFI_SUCCESS           The device state was set successfully.
+  @retval EFI_DEVICE_ERROR      The device is not functioning correctly and
+                                could not have the setting adjusted.
+  @retval EFI_UNSUPPORTED       The device does not have the ability to set
+                                its state.
+  @retval EFI_INVALID_PARAMETER KeyToggleState is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardSetState (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
+  IN EFI_KEY_TOGGLE_STATE               *KeyToggleState
+  )
+{
+  if (KeyToggleState == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Register a notification function for a particular keystroke for the
+  input device.
+
+  @param  This                    Protocol instance pointer.
+  @param  KeyData                 A pointer to a buffer that is filled in with
+                                  the keystroke information data for the key
+                                  that was pressed.
+  @param  KeyNotificationFunction Points to the function to be called when the
+                                  key sequence is typed specified by KeyData.
+  @param  NotifyHandle            Points to the unique handle assigned to the
+                                  registered notification.
+
+
+  @retval EFI_SUCCESS             The notification function was registered
+                                  successfully.
+  @retval EFI_OUT_OF_RESOURCES    Unable to allocate resources for necesssary
+                                  data structures.
+  @retval EFI_INVALID_PARAMETER   KeyData or NotifyHandle is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardRegisterKeyNotify (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
+  IN EFI_KEY_DATA                       *KeyData,
+  IN EFI_KEY_NOTIFY_FUNCTION            KeyNotificationFunction,
+  OUT VOID                              **NotifyHandle
+  )
+{
+  EFI_STATUS                            Status;
+  VIRTUAL_KEYBOARD_DEV                  *VirtualKeyboardPrivate;
+  EFI_TPL                               OldTpl;
+  VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY *NewNotify;
+  LIST_ENTRY                            *Link;
+  VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY *CurrentNotify;
+
+  if (KeyData == NULL ||
+      NotifyHandle == NULL ||
+      KeyNotificationFunction == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  VirtualKeyboardPrivate = TEXT_INPUT_EX_VIRTUAL_KEYBOARD_DEV_FROM_THIS (This);
+
+  //
+  // Enter critical section
+  //
+  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
+
+  //
+  // Return EFI_SUCCESS if the (KeyData, NotificationFunction) is already
+  // registered.
+  //
+  for (Link = VirtualKeyboardPrivate->NotifyList.ForwardLink;
+       Link != &VirtualKeyboardPrivate->NotifyList;
+       Link = Link->ForwardLink) {
+    CurrentNotify = CR (
+                      Link,
+                      VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY,
+                      NotifyEntry,
+                      VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE
+                      );
+    if (IsKeyRegistered (&CurrentNotify->KeyData, KeyData)) {
+      if (CurrentNotify->KeyNotificationFn == KeyNotificationFunction) {
+        *NotifyHandle = CurrentNotify;
+        Status = EFI_SUCCESS;
+        goto Exit;
+      }
+    }
+  }
+
+  //
+  // Allocate resource to save the notification function
+  //
+
+  NewNotify = (VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY *) AllocateZeroPool (sizeof (VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY));
+  if (NewNotify == NULL) {
+    Status = EFI_OUT_OF_RESOURCES;
+    goto Exit;
+  }
+
+  NewNotify->Signature         = VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE;
+  NewNotify->KeyNotificationFn = KeyNotificationFunction;
+  CopyMem (&NewNotify->KeyData, KeyData, sizeof (EFI_KEY_DATA));
+  InsertTailList (&VirtualKeyboardPrivate->NotifyList, &NewNotify->NotifyEntry);
+
+  *NotifyHandle                = NewNotify;
+  Status                       = EFI_SUCCESS;
+
+Exit:
+  //
+  // Leave critical section and return
+  //
+  gBS->RestoreTPL (OldTpl);
+  return Status;
+
+}
+
+/**
+  Remove a registered notification function from a particular keystroke.
+
+  @param  This                 Protocol instance pointer.
+  @param  NotificationHandle   The handle of the notification function
+                               being unregistered.
+
+  @retval EFI_SUCCESS             The notification function was unregistered
+                                  successfully.
+  @retval EFI_INVALID_PARAMETER   The NotificationHandle is invalid.
+
+**/
+EFI_STATUS
+EFIAPI
+VirtualKeyboardUnregisterKeyNotify (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *This,
+  IN VOID                               *NotificationHandle
+  )
+{
+  EFI_STATUS                            Status;
+  VIRTUAL_KEYBOARD_DEV                  *VirtualKeyboardPrivate;
+  EFI_TPL                               OldTpl;
+  LIST_ENTRY                            *Link;
+  VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY *CurrentNotify;
+
+  //
+  // Check incoming notification handle
+  //
+  if (NotificationHandle == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (((VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY *) NotificationHandle)->Signature !=
+      VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  VirtualKeyboardPrivate = TEXT_INPUT_EX_VIRTUAL_KEYBOARD_DEV_FROM_THIS (This);
+
+  //
+  // Enter critical section
+  //
+  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
+
+  for (Link = VirtualKeyboardPrivate->NotifyList.ForwardLink;
+       Link != &VirtualKeyboardPrivate->NotifyList;
+       Link = Link->ForwardLink) {
+    CurrentNotify = CR (
+                      Link,
+                      VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY,
+                      NotifyEntry,
+                      VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE
+                      );
+    if (CurrentNotify == NotificationHandle) {
+      //
+      // Remove the notification function from NotifyList and free resources
+      //
+      RemoveEntryList (&CurrentNotify->NotifyEntry);
+
+      Status = EFI_SUCCESS;
+      goto Exit;
+    }
+  }
+
+  //
+  // Can not find the specified Notification Handle
+  //
+  Status = EFI_INVALID_PARAMETER;
+
+Exit:
+  //
+  // Leave critical section and return
+  //
+  gBS->RestoreTPL (OldTpl);
+  return Status;
+}
+
+/**
+  Timer event handler: read a series of scancodes from 8042
+  and put them into memory scancode buffer.
+  it read as much scancodes to either fill
+  the memory buffer or empty the keyboard buffer.
+  It is registered as running under TPL_NOTIFY
+
+  @param Event       The timer event
+  @param Context     A KEYBOARD_CONSOLE_IN_DEV pointer
+
+**/
+VOID
+EFIAPI
+VirtualKeyboardTimerHandler (
+  IN EFI_EVENT    Event,
+  IN VOID         *Context
+  )
+{
+  EFI_TPL                                OldTpl;
+  LIST_ENTRY                             *Link;
+  EFI_KEY_DATA                           KeyData;
+  VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY  *CurrentNotify;
+  VIRTUAL_KEYBOARD_DEV                   *VirtualKeyboardPrivate;
+  VIRTUAL_KBD_KEY                        VirtualKey;
+
+  VirtualKeyboardPrivate = Context;
+
+  //
+  // Enter critical section
+  //
+  OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
+
+  if (VirtualKeyboardPrivate->PlatformVirtual &&
+      VirtualKeyboardPrivate->PlatformVirtual->Query) {
+    if (VirtualKeyboardPrivate->PlatformVirtual->Query (&VirtualKey) ==
+        FALSE) {
+      goto Exit;
+    }
+    // Found key
+    KeyData.Key.ScanCode = VirtualKey.Key.ScanCode;
+    KeyData.Key.UnicodeChar = VirtualKey.Key.UnicodeChar;
+    KeyData.KeyState.KeyShiftState  = EFI_SHIFT_STATE_VALID;
+    KeyData.KeyState.KeyToggleState = EFI_TOGGLE_STATE_VALID;
+    if (VirtualKeyboardPrivate->PlatformVirtual->Clear) {
+      VirtualKeyboardPrivate->PlatformVirtual->Clear (&VirtualKey);
+    }
+  } else {
+    goto Exit;
+  }
+
+  //
+  // Signal KeyNotify process event if this key pressed matches any key registered.
+  //
+  for (Link = VirtualKeyboardPrivate->NotifyList.ForwardLink;
+       Link != &VirtualKeyboardPrivate->NotifyList;
+       Link = Link->ForwardLink) {
+    CurrentNotify = CR (
+                      Link,
+                      VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY,
+                      NotifyEntry,
+                      VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE
+                      );
+    if (IsKeyRegistered (&CurrentNotify->KeyData, &KeyData)) {
+      //
+      // The key notification function needs to run at TPL_CALLBACK
+      // while current TPL is TPL_NOTIFY. It will be invoked in
+      // KeyNotifyProcessHandler() which runs at TPL_CALLBACK.
+      //
+      Enqueue (&VirtualKeyboardPrivate->QueueForNotify, &KeyData);
+      gBS->SignalEvent (VirtualKeyboardPrivate->KeyNotifyProcessEvent);
+    }
+  }
+
+  Enqueue (&VirtualKeyboardPrivate->Queue, &KeyData);
+
+Exit:
+  //
+  // Leave critical section and return
+  //
+  gBS->RestoreTPL (OldTpl);
+}
+
+/**
+  Process key notify.
+
+  @param  Event                 Indicates the event that invoke this function.
+  @param  Context               Indicates the calling context.
+**/
+VOID
+EFIAPI
+KeyNotifyProcessHandler (
+  IN  EFI_EVENT                 Event,
+  IN  VOID                      *Context
+  )
+{
+  EFI_STATUS                            Status;
+  VIRTUAL_KEYBOARD_DEV                  *VirtualKeyboardPrivate;
+  EFI_KEY_DATA                          KeyData;
+  LIST_ENTRY                            *Link;
+  LIST_ENTRY                            *NotifyList;
+  VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY *CurrentNotify;
+  EFI_TPL                               OldTpl;
+
+  VirtualKeyboardPrivate = (VIRTUAL_KEYBOARD_DEV *) Context;
+
+  //
+  // Invoke notification functions.
+  //
+  NotifyList = &VirtualKeyboardPrivate->NotifyList;
+  while (TRUE) {
+    //
+    // Enter critical section
+    //
+    OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
+    Status = Dequeue (&VirtualKeyboardPrivate->QueueForNotify, &KeyData);
+    //
+    // Leave critical section
+    //
+    gBS->RestoreTPL (OldTpl);
+    if (EFI_ERROR (Status)) {
+      break;
+    }
+    for (Link = GetFirstNode (NotifyList);
+         !IsNull (NotifyList, Link);
+         Link = GetNextNode (NotifyList, Link)) {
+      CurrentNotify = CR (Link,
+                        VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY,
+                        NotifyEntry,
+                        VIRTUAL_KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE
+                        );
+      if (IsKeyRegistered (&CurrentNotify->KeyData, &KeyData)) {
+        CurrentNotify->KeyNotificationFn (&KeyData);
+      }
+    }
+  }
+}
+
+/**
+  The user Entry Point for module VirtualKeyboard. The user code starts with
+  this function.
+
+  @param[in] ImageHandle    The firmware allocated handle for the EFI image.
+  @param[in] SystemTable    A pointer to the EFI System Table.
+
+  @retval EFI_SUCCESS       The entry point is executed successfully.
+  @retval other             Some error occurs when executing this entry point.
+
+**/
+EFI_STATUS
+EFIAPI
+InitializeVirtualKeyboard(
+  IN EFI_HANDLE           ImageHandle,
+  IN EFI_SYSTEM_TABLE     *SystemTable
+  )
+{
+  EFI_STATUS              Status;
+
+  //
+  // Install driver model protocol(s).
+  //
+  Status = EfiLibInstallDriverBindingComponentName2 (
+             ImageHandle,
+             SystemTable,
+             &gVirtualKeyboardDriverBinding,
+             ImageHandle,
+             &gVirtualKeyboardComponentName,
+             &gVirtualKeyboardComponentName2
+             );
+  ASSERT_EFI_ERROR (Status);
+
+  return Status;
+}