AudioDxe: Re-enable automatic switch to protocol GET mode on failure

It is still needed on some systems such as Acer E5 where DisconnectHda
does not work.

Changelog.md

@@ -11,6 +11,7 @@ OpenCore Changelog
 - Modified NVRAM logout hook to handle XML entities in string vars
 - Fixed CPU frequency calculation on AMD 0Fh family
 - Added kext blocker `Exclude` strategy for mkext
+- Re-enabled AudioDxe failover to protocol GET mode for systems such as Acer E5 where it works when DisconnectHda doesn't
 
 #### v0.9.7
 - Updated recovery_urls.txt

OpenCorePkg.dec

@@ -740,7 +740,7 @@
   ##   TRUE  - Use EFI_OPEN_PROTOCOL_GET_PROTOCOL if EFI_OPEN_PROTOCOL_BY_DRIVER fails.<BR>
   ##   FALSE - Do not use EFI_OPEN_PROTOCOL_GET_PROTOCOL.<BR>
   ## @Prompt Try EFI_OPEN_PROTOCOL_GET_PROTOCOL if EFI_OPEN_PROTOCOL_BY_DRIVER fails.
-  gOpenCorePkgTokenSpaceGuid.PcdAudioControllerTryProtocolGetMode|FALSE|BOOLEAN|0x00000007
+  gOpenCorePkgTokenSpaceGuid.PcdAudioControllerTryProtocolGetMode|TRUE|BOOLEAN|0x00000007
 
   ## Indicates if AudioDxe will use Pin Capabilities to identify outputs.<BR><BR>
   ##   TRUE  - Use Pin Capabilities to identify outputs.<BR>

Staging/AudioDxe/HdaController/HdaController.c

@@ -1104,7 +1104,8 @@ HdaControllerDriverBindingStart (
         //
         // No longer applied just if protocol gVMwareHdaProtocolGuid is found, since it also
         // allows sound on other devices where HDA controller is already connected, e.g. Macs.
-        // Now on Pcd because it appears never to be needed if DisconnectHda is applied.
+        // On many systems DisconnectHda can be used to avoid the need for this fallback, but
+        // on some - such as Acer E5 - DisconnectHda does not work but this method does.
         //
         DEBUG ((DEBUG_INFO, "HDA: %r using DRIVER mode, trying GET mode\n", Status));
         OpenMode = EFI_OPEN_PROTOCOL_GET_PROTOCOL;