Add details comments for the code flow to initialize Unicode Collation (2) support.

git-svn-id: https://edk2-fatdriver2.svn.sourceforge.net/svnroot/edk2-fatdriver2/trunk@29 efd2e655-3735-4b16-a529-16bfa2dd702b

1 files changed, 14 insertions, 0 deletions

diff --git a/FatPkg/EnhancedFatDxe/UnicodeCollation.c b/FatPkg/EnhancedFatDxe/UnicodeCollation.c
index 4a849af2eb..9e5db7b967 100644
--- a/FatPkg/EnhancedFatDxe/UnicodeCollation.c
+++ b/FatPkg/EnhancedFatDxe/UnicodeCollation.c
@@ -162,6 +162,12 @@ InitializeUnicodeCollationSupportWithConfig (
 /**

   Initialize Unicode Collation support.

 

+  This function searches Initialized Unicode Collation support based on PCDs:

+  PcdUnicodeCollation2Support and PcdUnicodeCollationSupport.

+  It first tries to locate Unicode Collation 2 protocol and matches it with current

+  platform language code. If for any reason the first attempt fails, it then tries to

+  use Unicode Collation Protocol.

+

   @param  AgentHandle          The handle used to open Unicode Collation (2) protocol.

 

   @retval EFI_SUCCESS          The Unicode Collation (2) protocol has been successfully located.

@@ -177,10 +183,18 @@ InitializeUnicodeCollationSupport (
   EFI_STATUS       Status;

 

   Status = EFI_UNSUPPORTED;

+

+  //

+  // First try to use RFC 3066 Unicode Collation 2 Protocol.

+  //

   if (FeaturePcdGet (PcdUnicodeCollation2Support)) {

     Status = InitializeUnicodeCollationSupportWithConfig (AgentHandle, &mRfc3066Lang);

   }

 

+  //

+  // If the attempt to use Unicode Collation 2 Protocol fails, then we fall back

+  // on the ISO 639-2 Unicode Collation Protocol.

+  //

   if (FeaturePcdGet (PcdUnicodeCollationSupport) && EFI_ERROR (Status)) {

     Status = InitializeUnicodeCollationSupportWithConfig (AgentHandle, &mIso639Lang);

   }