Add audio-haptic channel max amplitude

Add max amplitude setting from device vibrator service to the
AudioTrack, to be passed on to the ExternalVibrationUtils and
applied as a hard limit to clip haptic data above that amplitude,
after scaling.

Bug: 188025353
Test: manual
Change-Id: Ic83661c37a2e6109538c5905b97bed916920437e
diff --git a/services/audioflinger/PlaybackTracks.h b/services/audioflinger/PlaybackTracks.h
index 0929055..e9e98ca 100644
--- a/services/audioflinger/PlaybackTracks.h
+++ b/services/audioflinger/PlaybackTracks.h
@@ -19,6 +19,8 @@
     #error This header file should only be included from AudioFlinger.h
 #endif
 
+#include <math.h>
+
 // Checks and monitors OP_PLAY_AUDIO
 class OpPlayAudioMonitor : public RefBase {
 public:
@@ -161,6 +163,8 @@
             }
             /** Return at what intensity to play haptics, used in mixer. */
             os::HapticScale getHapticIntensity() const { return mHapticIntensity; }
+            /** Return the maximum amplitude allowed for haptics data, used in mixer. */
+            float getHapticMaxAmplitude() const { return mHapticMaxAmplitude; }
             /** Set intensity of haptic playback, should be set after querying vibrator service. */
             void    setHapticIntensity(os::HapticScale hapticIntensity) {
                 if (os::isValidHapticScale(hapticIntensity)) {
@@ -168,6 +172,12 @@
                     setHapticPlaybackEnabled(mHapticIntensity != os::HapticScale::MUTE);
                 }
             }
+            /** Set maximum amplitude allowed for haptic data, should be set after querying
+             *  vibrator service.
+             */
+            void    setHapticMaxAmplitude(float maxAmplitude) {
+                mHapticMaxAmplitude = maxAmplitude;
+            }
             sp<os::ExternalVibration> getExternalVibration() const { return mExternalVibration; }
 
             void    setTeePatches(TeePatches teePatches);
@@ -282,6 +292,8 @@
     bool                mHapticPlaybackEnabled = false; // indicates haptic playback enabled or not
     // intensity to play haptic data
     os::HapticScale mHapticIntensity = os::HapticScale::MUTE;
+    // max amplitude allowed for haptic data
+    float mHapticMaxAmplitude = NAN;
     class AudioVibrationController : public os::BnExternalVibrationController {
     public:
         explicit AudioVibrationController(Track* track) : mTrack(track) {}