commit c8f69a08a409fd163873d725c63f8d60259ae21d
author Phil Burk <philburk@google.com> Thu May 11 15:53:06 2017 -0700
committer Phil Burk <philburk@google.com> Tue May 16 10:34:05 2017 -0700
tree da3c5a871c2a78e109d02cf1c08cfb496d4aa3e6
parent feb0d87f693abd8fd2fa7ebfcdf7d91f0b95c131

aaudio: control MMAP mode using system properties

To facilitate testing of MMAP mode.

Bug: 38268547
Test: set properties, see framesPerBurst in write_sine_callback.cpp
Change-Id: I6e15c563215017f6a5020d89ac312ff8331afc4f
Signed-off-by: Phil Burk <philburk@google.com>

media/libaaudio/src/utility/AAudioUtilities.cpp

diff --git a/media/libaaudio/src/utility/AAudioUtilities.cpp b/media/libaaudio/src/utility/AAudioUtilities.cpp
index be2bd10..168ed86 100644
--- a/media/libaaudio/src/utility/AAudioUtilities.cpp
+++ b/media/libaaudio/src/utility/AAudioUtilities.cpp
@@ -18,6 +18,7 @@
 //#define LOG_NDEBUG 0
 #include <utils/Log.h>
 
+#include <cutils/properties.h>
 #include <stdint.h>
 #include <sys/types.h>
 #include <utils/Errors.h>
@@ -322,3 +323,52 @@
     *sizeInBytes = numFrames * bytesPerFrame;
     return AAUDIO_OK;
 }
+
+static int32_t AAudioProperty_getMMapProperty(const char *propName,
+                                              int32_t defaultValue,
+                                              const char * caller) {
+    int32_t prop = property_get_int32(AAUDIO_PROP_MMAP_ENABLED, defaultValue);
+    switch (prop) {
+        case AAUDIO_USE_NEVER:
+        case AAUDIO_USE_ALWAYS:
+        case AAUDIO_USE_AUTO:
+            break;
+        default:
+            ALOGE("%s: invalid = %d", caller, prop);
+            prop = defaultValue;
+            break;
+    }
+    return prop;
+}
+
+int32_t AAudioProperty_getMMapEnabled() {
+    return AAudioProperty_getMMapProperty(AAUDIO_PROP_MMAP_ENABLED,
+                                          AAUDIO_USE_NEVER, __func__);
+}
+
+int32_t AAudioProperty_getMMapExclusiveEnabled() {
+    return AAudioProperty_getMMapProperty(AAUDIO_PROP_MMAP_EXCLUSIVE_ENABLED,
+                                          AAUDIO_USE_NEVER, __func__);
+}
+
+int32_t AAudioProperty_getMixerBursts() {
+    const int32_t defaultBursts = 2; // arbitrary
+    const int32_t maxBursts = 1024; // arbitrary
+    int32_t prop = property_get_int32(AAUDIO_PROP_MIXER_BURSTS, defaultBursts); // use 2 for double buffered
+    if (prop < 1 || prop > maxBursts) {
+        ALOGE("AAudioProperty_getMixerBursts: invalid = %d", prop);
+        prop = defaultBursts;
+    }
+    return prop;
+}
+
+int32_t AAudioProperty_getHardwareBurstMinMicros() {
+    const int32_t defaultMicros = 1000; // arbitrary
+    const int32_t maxMicros = 1000 * 1000; // arbitrary
+    int32_t prop = property_get_int32(AAUDIO_PROP_HW_BURST_MIN_USEC, defaultMicros);
+    if (prop < 1 || prop > maxMicros) {
+        ALOGE("AAudioProperty_getHardwareBurstMinMicros: invalid = %d", prop);
+        prop = defaultMicros;
+    }
+    return prop;
+}