aaudio: fix IsochronousClockModel drift calculation
Correct an error that caused the timing window to jump
forward in time by one burst when a late timestamp was detected.
Bug: 133513175
Bug: 122680738
Bug: 123643363
Test: aaudio_loopback -tm -s20
Change-Id: I65c05d2ab123bcd347cb900de055c49c0c9beada
diff --git a/media/libaaudio/src/client/IsochronousClockModel.cpp b/media/libaaudio/src/client/IsochronousClockModel.cpp
index 747d0e1..d26b352 100644
--- a/media/libaaudio/src/client/IsochronousClockModel.cpp
+++ b/media/libaaudio/src/client/IsochronousClockModel.cpp
@@ -108,17 +108,24 @@
case STATE_RUNNING:
if (nanosDelta < expectedNanosDelta) {
// Earlier than expected timestamp.
- // This data is probably more accurate so use it.
- // or we may be drifting due to a slow HW clock.
-// ALOGD("processTimestamp() - STATE_RUNNING - %d < %d micros - EARLY",
-// (int) (nanosDelta / 1000), (int)(expectedNanosDelta / 1000));
+ // This data is probably more accurate, so use it.
+ // Or we may be drifting due to a fast HW clock.
+// int microsDelta = (int) (nanosDelta / 1000);
+// int expectedMicrosDelta = (int) (expectedNanosDelta / 1000);
+// ALOGD("processTimestamp() - STATE_RUNNING - %7d < %7d so %4d micros EARLY",
+// microsDelta, expectedMicrosDelta, (expectedMicrosDelta - microsDelta));
+
setPositionAndTime(framePosition, nanoTime);
} else if (nanosDelta > (expectedNanosDelta + mMaxLatenessInNanos)) {
// Later than expected timestamp.
-// ALOGD("processTimestamp() - STATE_RUNNING - %d > %d + %d micros - LATE",
-// (int) (nanosDelta / 1000), (int)(expectedNanosDelta / 1000),
-// (int) (mMaxLatenessInNanos / 1000));
- setPositionAndTime(framePosition - mFramesPerBurst, nanoTime - mMaxLatenessInNanos);
+// int microsDelta = (int) (nanosDelta / 1000);
+// int expectedMicrosDeadline = (int) ((expectedNanosDelta + mMaxLatenessInNanos) / 1000);
+// ALOGD("processTimestamp() - STATE_RUNNING - %7d > %7d so %4d micros LATE",
+// microsDelta, expectedMicrosDeadline, (microsDelta - expectedMicrosDeadline));
+
+ // When we are late it may be because of preemption in the kernel or
+ // we may be drifting due to a slow HW clock.
+ setPositionAndTime(framePosition, nanoTime - mMaxLatenessInNanos);
}
break;
default:
