updated the Bus Driver that is able to create all or one of its child handles on each call to Start() not to create new child handle if RemainingDeviepath is the End of Device Path Node, per UEFI 2.3.

The others changes include:
1. Check RemainingDevicePath at beginning of Supported(), make sure it has been verified before Start() is called.
2. Check IO protocol firstly rather than EfiDevicePathProtocolGuid, reduce the times entering into Start() function because EfiDevicePathProtocolGuid existed on most of handle.
3. If no any child device is created on last time, and RemainingDevicePath is valid Uart Devcie path, go on creating child device handle based on this RemainingDevicePath.


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9262 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 50 insertions, 29 deletions

diff --git a/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c b/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c
index 5e3b689..b68d45f 100644
--- a/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c
+++ b/MdeModulePkg/Universal/Console/TerminalDxe/Terminal.c
@@ -2,7 +2,7 @@
   Produces Simple Text Input Protocol, Simple Text Input Extended Protocol and

   Simple Text Output Protocol upon Serial IO Protocol.

 

-Copyright (c) 2006 - 2008, Intel Corporation. <BR>

+Copyright (c) 2006 - 2009, Intel Corporation. <BR>

 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

@@ -124,34 +124,46 @@ TerminalDriverBindingSupported (
   // device path that describes a terminal communications protocol.

   //

   if (RemainingDevicePath != NULL) {

-

-    Node = (VENDOR_DEVICE_PATH *) RemainingDevicePath;

-

-    if (Node->Header.Type != MESSAGING_DEVICE_PATH ||

-        Node->Header.SubType != MSG_VENDOR_DP ||

-        DevicePathNodeLength(&Node->Header) != sizeof(VENDOR_DEVICE_PATH)) {

-

-      return EFI_UNSUPPORTED;

-

-    }

     //

-    // only supports PC ANSI, VT100, VT100+ and VT-UTF8 terminal types

+    // Check if RemainingDevicePath is the End of Device Path Node, 

+    // if yes, go on checking other conditions

     //

-    if (!CompareGuid (&Node->Guid, &gEfiPcAnsiGuid) &&

-        !CompareGuid (&Node->Guid, &gEfiVT100Guid) &&

-        !CompareGuid (&Node->Guid, &gEfiVT100PlusGuid) &&

-        !CompareGuid (&Node->Guid, &gEfiVTUTF8Guid)) {

-

-      return EFI_UNSUPPORTED;

+    if (!IsDevicePathEnd (RemainingDevicePath)) {

+      //

+      // If RemainingDevicePath isn't the End of Device Path Node,

+      // check its validation

+      //

+      Node = (VENDOR_DEVICE_PATH *) RemainingDevicePath;

+  

+      if (Node->Header.Type != MESSAGING_DEVICE_PATH ||

+          Node->Header.SubType != MSG_VENDOR_DP ||

+          DevicePathNodeLength(&Node->Header) != sizeof(VENDOR_DEVICE_PATH)) {

+  

+        return EFI_UNSUPPORTED;

+  

+      }

+      //

+      // only supports PC ANSI, VT100, VT100+ and VT-UTF8 terminal types

+      //

+      if (!CompareGuid (&Node->Guid, &gEfiPcAnsiGuid) &&

+          !CompareGuid (&Node->Guid, &gEfiVT100Guid) &&

+          !CompareGuid (&Node->Guid, &gEfiVT100PlusGuid) &&

+          !CompareGuid (&Node->Guid, &gEfiVTUTF8Guid)) {

+  

+        return EFI_UNSUPPORTED;

+      }

     }

   }

   //

   // Open the IO Abstraction(s) needed to perform the supported test

+  // The Controller must support the Serial I/O Protocol.

+  // This driver is a bus driver with at most 1 child device, so it is

+  // ok for it to be already started.

   //

   Status = gBS->OpenProtocol (

                   Controller,

-                  &gEfiDevicePathProtocolGuid,

-                  (VOID **) &ParentDevicePath,

+                  &gEfiSerialIoProtocolGuid,

+                  (VOID **) &SerialIo,

                   This->DriverBindingHandle,

                   Controller,

                   EFI_OPEN_PROTOCOL_BY_DRIVER

@@ -164,22 +176,23 @@ TerminalDriverBindingSupported (
     return Status;

   }

 

+  //

+  // Close the I/O Abstraction(s) used to perform the supported test

+  //

   gBS->CloseProtocol (

         Controller,

-        &gEfiDevicePathProtocolGuid,

+        &gEfiSerialIoProtocolGuid,

         This->DriverBindingHandle,

         Controller

         );

 

   //

-  // The Controller must support the Serial I/O Protocol.

-  // This driver is a bus driver with at most 1 child device, so it is

-  // ok for it to be already started.

+  // Open the EFI Device Path protocol needed to perform the supported test

   //

   Status = gBS->OpenProtocol (

                   Controller,

-                  &gEfiSerialIoProtocolGuid,

-                  (VOID **) &SerialIo,

+                  &gEfiDevicePathProtocolGuid,

+                  (VOID **) &ParentDevicePath,

                   This->DriverBindingHandle,

                   Controller,

                   EFI_OPEN_PROTOCOL_BY_DRIVER

@@ -191,12 +204,13 @@ TerminalDriverBindingSupported (
   if (EFI_ERROR (Status)) {

     return Status;

   }

+

   //

-  // Close the I/O Abstraction(s) used to perform the supported test

+  // Close protocol, don't use device path protocol in the Support() function

   //

   gBS->CloseProtocol (

         Controller,

-        &gEfiSerialIoProtocolGuid,

+        &gEfiDevicePathProtocolGuid,

         This->DriverBindingHandle,

         Controller

         );

@@ -353,8 +367,9 @@ TerminalDriverBindingStart (
 

     CopyMem (&DefaultNode->Guid, gTerminalType[TerminalType], sizeof (EFI_GUID));

     RemainingDevicePath = (EFI_DEVICE_PATH_PROTOCOL *) DefaultNode;

-  } else {

+  } else if (!IsDevicePathEnd (RemainingDevicePath)) {

     //

+    // If RemainingDevicePath isn't the End of Device Path Node, 

     // Use the RemainingDevicePath to determine the terminal type

     //

     Node = (VENDOR_DEVICE_PATH *)RemainingDevicePath;

@@ -369,6 +384,12 @@ TerminalDriverBindingStart (
     } else {

       goto Error;

     }

+  } else {

+    //

+    // If RemainingDevicePath is the End of Device Path Node,

+    // skip enumerate any device and return EFI_SUCESSS

+    // 

+    return EFI_SUCCESS;

   }

 

   //