diff --git a/audio/4.0/IDevice.hal b/audio/4.0/IDevice.hal
index 23cf9fb..2f121c1 100644
--- a/audio/4.0/IDevice.hal
+++ b/audio/4.0/IDevice.hal
@@ -117,7 +117,7 @@
             AudioIoHandle ioHandle,
             DeviceAddress device,
             AudioConfig config,
-            AudioOutputFlag flags) generates (
+            bitfield<AudioOutputFlag> flags) generates (
                     Result retval,
                     IStreamOut outStream,
                     AudioConfig suggestedConfig);
@@ -140,7 +140,7 @@
             AudioIoHandle ioHandle,
             DeviceAddress device,
             AudioConfig config,
-            AudioInputFlag flags,
+            bitfield<AudioInputFlag> flags,
             AudioSource source) generates (
                     Result retval,
                     IStreamIn inStream,
diff --git a/audio/4.0/IStream.hal b/audio/4.0/IStream.hal
index 62b8d03..306152b 100644
--- a/audio/4.0/IStream.hal
+++ b/audio/4.0/IStream.hal
@@ -88,7 +88,7 @@
      *
      * @return mask channel mask.
      */
-    getChannelMask() generates (AudioChannelMask mask);
+    getChannelMask() generates (bitfield<AudioChannelMask> mask);
 
     /**
      * Return supported channel masks of the stream. Calling this method is
@@ -101,7 +101,7 @@
      * @return masks supported audio masks.
      */
     getSupportedChannelMasks(AudioFormat format)
-            generates (Result retval, vec<AudioChannelMask> masks);
+            generates (Result retval, vec<bitfield<AudioChannelMask>> masks);
 
     /**
      * Sets the channel mask of the stream. Calling this method is equivalent to
@@ -111,7 +111,7 @@
      * @param format audio format.
      * @return retval operation completion status.
      */
-    setChannelMask(AudioChannelMask mask) generates (Result retval);
+    setChannelMask(bitfield<AudioChannelMask> mask) generates (Result retval);
 
     /**
      * Return the audio format of the stream.
@@ -148,7 +148,7 @@
      * @return format audio format.
      */
     getAudioProperties() generates (
-            uint32_t sampleRateHz, AudioChannelMask mask, AudioFormat format);
+            uint32_t sampleRateHz, bitfield<AudioChannelMask> mask, AudioFormat format);
 
     /**
      * Applies audio effect to the stream.
@@ -183,7 +183,7 @@
      * @return retval operation completion status: OK or NOT_SUPPORTED.
      * @return device set of device(s) which this stream is connected to.
      */
-    getDevice() generates (Result retval, AudioDevice device);
+    getDevice() generates (Result retval, bitfield<AudioDevice> device);
 
     /**
      * Connects the stream to the device.
diff --git a/audio/common/4.0/types.hal b/audio/common/4.0/types.hal
index ab4bce8..5212dcd 100644
--- a/audio/common/4.0/types.hal
+++ b/audio/common/4.0/types.hal
@@ -678,7 +678,7 @@
  */
 struct AudioOffloadInfo {
     uint32_t sampleRateHz;
-    AudioChannelMask channelMask;
+    bitfield<AudioChannelMask> channelMask;
     AudioFormat format;
     AudioStreamType streamType;
     uint32_t bitRatePerSecond;
@@ -695,7 +695,7 @@
  */
 struct AudioConfig {
     uint32_t sampleRateHz;
-    AudioChannelMask channelMask;
+    bitfield<AudioChannelMask> channelMask;
     AudioFormat format;
     AudioOffloadInfo offloadInfo;
     uint64_t frameCount;
@@ -723,8 +723,8 @@
  * A gain stage is always attached to an audio port.
  */
 struct AudioGain {
-    AudioGainMode mode;
-    AudioChannelMask channelMask; // channels which gain an be controlled
+    bitfield<AudioGainMode> mode;
+    bitfield<AudioChannelMask> channelMask; // channels which gain an be controlled
     int32_t minValue;     // minimum gain value in millibels
     int32_t maxValue;     // maximum gain value in millibels
     int32_t defaultValue; // default gain value in millibels
@@ -822,9 +822,9 @@
  */
 struct AudioPortConfig {
     AudioPortHandle id;
-    AudioPortConfigMask configMask;
+    bitfield<AudioPortConfigMask> configMask;
     uint32_t sampleRateHz;
-    AudioChannelMask channelMask;
+    bitfield<AudioChannelMask> channelMask;
     AudioFormat format;
     AudioGainConfig gain;
     AudioPortType type;  // type is used as a discriminator for Ext union
@@ -879,7 +879,7 @@
     AudioPortRole role;
     string name;
     vec<uint32_t> sampleRates;
-    vec<AudioChannelMask> channelMasks;
+    vec<bitfield<AudioChannelMask>> channelMasks;
     vec<AudioFormat> formats;
     vec<AudioGain> gains;
     AudioPortConfig activeConfig; // current audio port configuration
diff --git a/audio/effect/4.0/IEffect.hal b/audio/effect/4.0/IEffect.hal
index a1bfd43..afc0237 100644
--- a/audio/effect/4.0/IEffect.hal
+++ b/audio/effect/4.0/IEffect.hal
@@ -82,7 +82,7 @@
      * @return retval operation completion status.
      */
     @callflow(next={"*"})
-    setDevice(AudioDevice device) generates (Result retval);
+    setDevice(bitfield<AudioDevice> device) generates (Result retval);
 
     /**
      * Set and get volume. Used by audio framework to delegate volume control to
@@ -155,7 +155,7 @@
      * @return retval operation completion status.
      */
     @callflow(next={"*"})
-    setInputDevice(AudioDevice device) generates (Result retval);
+    setInputDevice(bitfield<AudioDevice> device) generates (Result retval);
 
     /**
      * Read audio parameters configurations for input and output buffers.
diff --git a/audio/effect/4.0/IVirtualizerEffect.hal b/audio/effect/4.0/IVirtualizerEffect.hal
index b98ad3f..52038ca 100644
--- a/audio/effect/4.0/IVirtualizerEffect.hal
+++ b/audio/effect/4.0/IVirtualizerEffect.hal
@@ -47,7 +47,8 @@
     getStrength() generates (Result retval, uint16_t strength);
 
     struct SpeakerAngle {
-        AudioChannelMask mask; // speaker channel mask (1 bit set).
+        /** Speaker channel mask */
+        bitfield<AudioChannelMask> mask;
         // all angles are expressed in degrees and
         // are relative to the listener.
         int16_t azimuth; // 0 is the direction the listener faces
@@ -60,7 +61,7 @@
      * Retrieves virtual speaker angles for the given channel mask on the
      * specified device.
      */
-    getVirtualSpeakerAngles(AudioChannelMask mask, AudioDevice device)
+    getVirtualSpeakerAngles(bitfield<AudioChannelMask> mask, AudioDevice device)
             generates (Result retval, vec<SpeakerAngle> speakerAngles);
 
     /**
diff --git a/audio/effect/4.0/types.hal b/audio/effect/4.0/types.hal
index 80d627e..57f96e3 100644
--- a/audio/effect/4.0/types.hal
+++ b/audio/effect/4.0/types.hal
@@ -255,7 +255,7 @@
 struct EffectBufferConfig {
     AudioBuffer buffer;
     uint32_t samplingRateHz;
-    AudioChannelMask channels;
+    bitfield<AudioChannelMask> channels;
     AudioFormat format;
     EffectBufferAccess accessMode;
     EffectConfigParameters mask;
@@ -274,8 +274,8 @@
 };
 
 struct EffectAuxChannelsConfig {
-    AudioChannelMask mainChannels;  // channel mask for main channels
-    AudioChannelMask auxChannels;   // channel mask for auxiliary channels
+    bitfield<AudioChannelMask> mainChannels;  // channel mask for main channels
+    bitfield<AudioChannelMask> auxChannels;   // channel mask for auxiliary channels
 };
 
 struct EffectOffloadParameter {