Audio HAL: fixes for issues discovered after client conversion
Several issues addressed:
-- added IDevice.supportsAudioPatches to query whether
create/removeAudioPatch is actually supported by HAL;
-- IStreamOutCallback proxy needs to be owned by IStreamOut
implementation. In order for the client to reset the reference,
added method IStreamOut.clearCallback;
-- IDevice.open{Input|Output}Stream need to return a "suggested" audio
config from HAL;
-- code for converting between system/audio.h and HIDL
data structures has been moved to
android.hardware.audio.common@2.0-util library for reuse;
-- added a workaround for the issue with QC effects HAL trying to write
into the input parameters buffer, which is r/o by Binder design.
Bug: 30222631
Change-Id: I64af24d79c12d6ac3b0f87d085a821913e29237b
Test: tried using with WIP HIDL client on N5X
diff --git a/audio/2.0/IStreamOut.hal b/audio/2.0/IStreamOut.hal
index 55a852d..4ba3b2f 100644
--- a/audio/2.0/IStreamOut.hal
+++ b/audio/2.0/IStreamOut.hal
@@ -90,11 +90,25 @@
* Calling this function implies that all future 'write' and 'drain'
* must be non-blocking and use the callback to signal completion.
*
+ * 'clearCallback' method needs to be called in order to release the local
+ * callback proxy on the server side and thus dereference the callback
+ * implementation on the client side.
+ *
* @return retval operation completion status.
*/
setCallback(IStreamOutCallback callback) generates (Result retval);
/*
+ * Clears the callback previously set via 'setCallback' method.
+ *
+ * Warning: failure to call this method results in callback implementation
+ * on the client side being held until the HAL server termination.
+ *
+ * @return retval operation completion status: OK or NOT_SUPPORTED.
+ */
+ clearCallback() generates (Result retval);
+
+ /*
* Returns whether HAL supports pausing and resuming of streams.
*
* @return supportsPause true if pausing is supported.