diff --git a/audio/aidl/aidl_api/android.hardware.audio.effect/current/android/hardware/audio/effect/BassBoost.aidl b/audio/aidl/aidl_api/android.hardware.audio.effect/current/android/hardware/audio/effect/BassBoost.aidl
index 979ebb8..09ad015 100644
--- a/audio/aidl/aidl_api/android.hardware.audio.effect/current/android/hardware/audio/effect/BassBoost.aidl
+++ b/audio/aidl/aidl_api/android.hardware.audio.effect/current/android/hardware/audio/effect/BassBoost.aidl
@@ -36,6 +36,8 @@
 union BassBoost {
   android.hardware.audio.effect.VendorExtension vendor;
   int strengthPm;
+  const int MIN_PER_MILLE_STRENGTH = 0;
+  const int MAX_PER_MILLE_STRENGTH = 1000;
   @VintfStability
   union Id {
     int vendorExtensionTag;
diff --git a/audio/aidl/android/hardware/audio/effect/BassBoost.aidl b/audio/aidl/android/hardware/audio/effect/BassBoost.aidl
index 810c188..9e5d8aa 100644
--- a/audio/aidl/android/hardware/audio/effect/BassBoost.aidl
+++ b/audio/aidl/android/hardware/audio/effect/BassBoost.aidl
@@ -59,6 +59,16 @@
     }
 
     /**
+     * Minimal possible per mille strength.
+     */
+    const int MIN_PER_MILLE_STRENGTH = 0;
+
+    /**
+     * Maximum possible per mille strength.
+     */
+    const int MAX_PER_MILLE_STRENGTH = 1000;
+
+    /**
      * The per mille strength of the bass boost effect.
      *
      * If the implementation does not support per mille accuracy for setting the strength, it is