diff --git a/audio/aidl/common/include/Utils.h b/audio/aidl/common/include/Utils.h
index d87bbd4..32c36b8 100644
--- a/audio/aidl/common/include/Utils.h
+++ b/audio/aidl/common/include/Utils.h
@@ -19,6 +19,7 @@
 #include <algorithm>
 #include <array>
 #include <initializer_list>
+#include <regex>
 #include <type_traits>
 
 #include <aidl/android/media/audio/common/AudioChannelLayout.h>
@@ -133,6 +134,18 @@
            kValidAudioModes.end();
 }
 
+static inline bool maybeVendorExtension(const std::string& s) {
+    // Only checks whether the string starts with the "vendor prefix".
+    static const std::string vendorPrefix = "VX_";
+    return s.size() > vendorPrefix.size() && s.substr(0, vendorPrefix.size()) == vendorPrefix;
+}
+
+static inline bool isVendorExtension(const std::string& s) {
+    // Must be the same as defined in {Playback|Record}TrackMetadata.aidl
+    static const std::regex vendorExtension("VX_[A-Z0-9]{3,}_[_A-Z0-9]+");
+    return std::regex_match(s.begin(), s.end(), vendorExtension);
+}
+
 // The helper functions defined below are only applicable to the case when an enum type
 // specifies zero-based bit positions, not bit masks themselves. This is why instantiation
 // is restricted to certain enum types.
diff --git a/audio/common/all-versions/default/HidlUtils.h b/audio/common/all-versions/default/HidlUtils.h
index ad9dee2..844a651 100644
--- a/audio/common/all-versions/default/HidlUtils.h
+++ b/audio/common/all-versions/default/HidlUtils.h
@@ -81,7 +81,7 @@
 #endif
 
 #if MAJOR_VERSION >= 7
-    static constexpr char sAudioTagSeparator = ';';
+    static constexpr char sAudioTagSeparator = AUDIO_ATTRIBUTES_TAGS_SEPARATOR;
 
     static status_t audioChannelMaskFromHal(audio_channel_mask_t halChannelMask, bool isInput,
                                             AudioChannelMask* channelMask);