[PATCH] MdeModulePkg ConSplitterDxe: Support toggle state sync

[Star Zeng <star.zeng@intel.com>]

Register key notify for toggle state (CapsLock, NumLock and ScrollLock)
sync between multiple keyboards.
The implementation for this feature requires keyboard driver supports
EFI_KEY_STATE_EXPOSED, and turns on physical TextInEx partial key
report for toggle state sync.
The virtual TextInEx will report the partial key after it is required
by calling SetState(X | KEY_STATE_VALID_EXPOSED) explicitly.

Cc: Ruiyu Ni <Ruiyu.ni@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Feng Tian <feng.tian@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
---
 .../Universal/Console/ConSplitterDxe/ConSplitter.c | 208 ++++++++++++++++++++-
 .../Universal/Console/ConSplitterDxe/ConSplitter.h |   5 +-
 2 files changed, 206 insertions(+), 7 deletions(-)

diff --git a/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.c b/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.c
index 493bcbafdf39..203ad7b06e20 100644
--- a/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.c
+++ b/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.c
@@ -67,6 +67,8 @@ GLOBAL_REMOVE_IF_UNREFERENCED TEXT_IN_SPLITTER_PRIVATE_DATA  mConIn = {
     (LIST_ENTRY *) NULL,
     (LIST_ENTRY *) NULL
   },
+  0,
+  FALSE,
 
   {
     ConSplitterSimplePointerReset,
@@ -301,6 +303,157 @@ EFI_DRIVER_BINDING_PROTOCOL           gConSplitterAbsolutePointerDriverBinding =
 };
 
 /**
+  Sync current toggle state to new console input device.
+
+  @param TextInEx       Simple Text Input Ex Input protocol pointer.
+
+**/
+VOID
+ToggleStateSyncToNewConInDev (
+  IN EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  *TextInEx
+  )
+{
+  //
+  // Sync current toggle state to this new console input device.
+  //
+  TextInEx->SetState (TextInEx, &mConIn.PhysicalKeyToggleState);
+}
+
+/**
+  Key notify for toggle state sync.
+
+  @param KeyData        A pointer to a buffer that is filled in with
+                        the keystroke information for the key that was
+                        pressed.
+
+  @retval EFI_SUCCESS   Toggle state sync successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+ToggleStateSyncKeyNotify (
+  IN EFI_KEY_DATA   *KeyData
+  )
+{
+  UINTN     Index;
+
+  if (((KeyData->KeyState.KeyToggleState & KEY_STATE_VALID_EXPOSED) == KEY_STATE_VALID_EXPOSED) &&
+      (KeyData->KeyState.KeyToggleState != mConIn.PhysicalKeyToggleState)) {
+    //
+    // There is toggle state change, sync to other console input devices.
+    //
+    for (Index = 0; Index < mConIn.CurrentNumberOfExConsoles; Index++) {
+      mConIn.TextInExList[Index]->SetState (
+                                    mConIn.TextInExList[Index],
+                                    &KeyData->KeyState.KeyToggleState
+                                    );
+    }
+    mConIn.PhysicalKeyToggleState = KeyData->KeyState.KeyToggleState;
+    DEBUG ((EFI_D_INFO, "Current toggle state is 0x%02x\n", mConIn.PhysicalKeyToggleState));
+  }
+
+  return EFI_SUCCESS;
+}
+
+/**
+  Initialization for toggle state sync.
+
+  @param Private                    Text In Splitter pointer.
+
+**/
+VOID
+ToggleStateSyncInitialization (
+  IN TEXT_IN_SPLITTER_PRIVATE_DATA  *Private
+  )
+{
+  EFI_KEY_DATA      KeyData;
+  VOID              *NotifyHandle;
+
+  //
+  // Initialize PhysicalKeyToggleState that will be synced to new console
+  // input device to turn on physical TextInEx partial key report for
+  // toggle state sync.
+  //
+  Private->PhysicalKeyToggleState = KEY_STATE_VALID_EXPOSED;
+
+  //
+  // Initialize VirtualKeyStateExported to let the virtual TextInEx not report
+  // the partial key even though the physical TextInEx turns on the partial
+  // key report. The virtual TextInEx will report the partial key after it is
+  // required by calling SetState(X | KEY_STATE_VALID_EXPOSED) explicitly.
+  //
+  Private->VirtualKeyStateExported = FALSE;
+
+  //
+  // Register key notify for toggle state sync.
+  //
+  KeyData.Key.ScanCode = SCAN_NULL;
+  KeyData.Key.UnicodeChar = CHAR_NULL;
+  KeyData.KeyState.KeyShiftState = 0;
+  KeyData.KeyState.KeyToggleState = 0;
+  Private->TextInEx.RegisterKeyNotify (
+                      &Private->TextInEx,
+                      &KeyData,
+                      ToggleStateSyncKeyNotify,
+                      &NotifyHandle
+                      );
+}
+
+/**
+  Reinitialization for toggle state sync.
+
+  @param Private                    Text In Splitter pointer.
+
+**/
+VOID
+ToggleStateSyncReInitialization (
+  IN TEXT_IN_SPLITTER_PRIVATE_DATA  *Private
+  )
+{
+  UINTN             Index;
+
+  //
+  // Reinitialize PhysicalKeyToggleState that will be synced to new console
+  // input device to turn on physical TextInEx partial key report for
+  // toggle state sync.
+  //
+  Private->PhysicalKeyToggleState = KEY_STATE_VALID_EXPOSED;
+
+  //
+  // Reinitialize VirtualKeyStateExported to let the virtual TextInEx not report
+  // the partial key even though the physical TextInEx turns on the partial
+  // key report. The virtual TextInEx will report the partial key after it is
+  // required by calling SetState(X | KEY_STATE_VALID_EXPOSED) explicitly.
+  //
+  Private->VirtualKeyStateExported = FALSE;
+
+  for (Index = 0; Index < Private->CurrentNumberOfExConsoles; Index++) {
+    Private->TextInExList[Index]->SetState (
+                                    Private->TextInExList[Index],
+                                    &Private->PhysicalKeyToggleState
+                                    );
+  }
+}
+
+/**
+  Toggle state sync hook SetState.
+
+  @param KeyToggleState     Pointer to key toggle state.
+
+**/
+VOID
+ToggleStateSyncHookSetState (
+  IN OUT EFI_KEY_TOGGLE_STATE   *KeyToggleState
+  )
+{
+  //
+  // Always turn on physical TextInEx partial key report for
+  // toggle state sync.
+  //
+  *KeyToggleState |= EFI_KEY_STATE_EXPOSED;
+}
+
+/**
   The Entry Point for module ConSplitter. The user code starts with this function.
 
   Installs driver module protocols and. Creates virtual device handles for ConIn,
@@ -538,6 +691,8 @@ ConSplitterTextInConstructor (
 
   InitializeListHead (&ConInPrivate->NotifyList);
 
+  ToggleStateSyncInitialization (ConInPrivate);
+
   ConInPrivate->AbsolutePointer.Mode = &ConInPrivate->AbsolutePointerMode;
   //
   // Allocate buffer for Absolute Pointer device
@@ -1890,6 +2045,8 @@ ConSplitterTextInExAddDevice (
   Private->TextInExList[Private->CurrentNumberOfExConsoles] = TextInEx;
   Private->CurrentNumberOfExConsoles++;
 
+  ToggleStateSyncToNewConInDev (TextInEx);
+
   //
   // Extra CheckEvent added to reduce the double CheckEvent().
   //
@@ -3321,6 +3478,10 @@ ConSplitterTextInReset (
     }
   }
 
+  if (!EFI_ERROR (ReturnStatus)) {
+    ToggleStateSyncReInitialization (Private);
+  }
+
   return ReturnStatus;
 }
 
@@ -3363,8 +3524,18 @@ ConSplitterTextInPrivateReadKeyStroke (
                                           &CurrentKey
                                           );
     if (!EFI_ERROR (Status)) {
-      *Key = CurrentKey;
-      return Status;
+      //
+      // If it is partial keystroke, skip it.
+      //
+      if ((CurrentKey.ScanCode == CHAR_NULL) && (CurrentKey.UnicodeChar == SCAN_NULL)) {
+        //
+        // Try to read key from this physical console input device again.
+        //
+        Index--;
+      } else {
+        *Key = CurrentKey;
+        return Status;
+      }
     }
   }
 
@@ -3542,6 +3713,10 @@ ConSplitterTextInResetEx (
     }
   }
 
+  if (!EFI_ERROR (ReturnStatus)) {
+    ToggleStateSyncReInitialization (Private);
+  }
+
   return ReturnStatus;
 
 }
@@ -3607,8 +3782,22 @@ ConSplitterTextInReadKeyStrokeEx (
                                           &CurrentKeyData
                                           );
     if (!EFI_ERROR (Status)) {
-      CopyMem (KeyData, &CurrentKeyData, sizeof (CurrentKeyData));
-      return Status;
+      //
+      // If it is partial keystroke, check if virtual KeyState has been required to be exposed.
+      //
+      if ((CurrentKeyData.Key.ScanCode == CHAR_NULL) && (CurrentKeyData.Key.UnicodeChar == SCAN_NULL)) {
+        if (Private->VirtualKeyStateExported) {
+          CopyMem (KeyData, &CurrentKeyData, sizeof (CurrentKeyData));
+          return Status;
+        }
+        //
+        // Try to read key from this physical console input device again.
+        //
+        Index--;
+      } else {
+        CopyMem (KeyData, &CurrentKeyData, sizeof (CurrentKeyData));
+        return Status;
+      }
     }
   }
 
@@ -3641,6 +3830,7 @@ ConSplitterTextInSetState (
   TEXT_IN_SPLITTER_PRIVATE_DATA *Private;
   EFI_STATUS                    Status;
   UINTN                         Index;
+  EFI_KEY_TOGGLE_STATE          PhysicalKeyToggleState;
 
   if (KeyToggleState == NULL) {
     return EFI_INVALID_PARAMETER;
@@ -3648,6 +3838,9 @@ ConSplitterTextInSetState (
 
   Private = TEXT_IN_EX_SPLITTER_PRIVATE_DATA_FROM_THIS (This);
 
+  PhysicalKeyToggleState = *KeyToggleState;
+  ToggleStateSyncHookSetState (&PhysicalKeyToggleState);
+
   //
   // if no physical console input device exists, return EFI_SUCCESS;
   // otherwise return the status of setting state of physical console input device
@@ -3655,13 +3848,16 @@ ConSplitterTextInSetState (
   for (Index = 0; Index < Private->CurrentNumberOfExConsoles; Index++) {
     Status = Private->TextInExList[Index]->SetState (
                                              Private->TextInExList[Index],
-                                             KeyToggleState
+                                             &PhysicalKeyToggleState
                                              );
     if (EFI_ERROR (Status)) {
       return Status;
     }
   }
 
+  Private->PhysicalKeyToggleState = PhysicalKeyToggleState;
+  Private->VirtualKeyStateExported = (((*KeyToggleState) & EFI_KEY_STATE_EXPOSED) != 0);
+
   return EFI_SUCCESS;
 
 }
@@ -3765,7 +3961,7 @@ ConSplitterTextInRegisterKeyNotify (
     }
   }
 
-  InsertTailList (&mConIn.NotifyList, &NewNotify->NotifyEntry);
+  InsertTailList (&Private->NotifyList, &NewNotify->NotifyEntry);
 
   *NotifyHandle                = NewNotify;
 
diff --git a/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.h b/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.h
index e32abbaea133..99ac5b55d302 100644
--- a/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.h
+++ b/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.h
@@ -1,7 +1,7 @@
 /** @file
   Private data structures for the Console Splitter driver
 
-Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2016, Intel Corporation. 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
@@ -88,6 +88,7 @@ typedef struct {
   UINTN   Rows;
 } TEXT_OUT_SPLITTER_QUERY_DATA;
 
+#define KEY_STATE_VALID_EXPOSED (EFI_TOGGLE_STATE_VALID | EFI_KEY_STATE_EXPOSED)
 
 #define TEXT_IN_EX_SPLITTER_NOTIFY_SIGNATURE    SIGNATURE_32 ('T', 'i', 'S', 'n')
 
@@ -128,6 +129,8 @@ typedef struct {
   EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL  **TextInExList;
   UINTN                              TextInExListCount;
   LIST_ENTRY                         NotifyList;
+  EFI_KEY_TOGGLE_STATE               PhysicalKeyToggleState;
+  BOOLEAN                            VirtualKeyStateExported;
 
 
   EFI_SIMPLE_POINTER_PROTOCOL        SimplePointer;
-- 
2.7.0.windows.1