1 files changed, 22 insertions, 2 deletions
diff --git a/services/camera/libcameraservice/device3/Camera3InputStream.cpp b/services/camera/libcameraservice/device3/Camera3InputStream.cpp
index 5aa9a3e..e1c492b 100644
--- a/services/camera/libcameraservice/device3/Camera3InputStream.cpp
+++ b/services/camera/libcameraservice/device3/Camera3InputStream.cpp
@@ -199,13 +199,33 @@ status_t Camera3InputStream::configureQueueLocked() {
     assert(mMaxSize == 0);
     assert(camera3_stream::format != HAL_PIXEL_FORMAT_BLOB);
 
-    mTotalBufferCount = BufferQueue::MIN_UNDEQUEUED_BUFFERS +
-                        camera3_stream::max_buffers;
     mDequeuedBufferCount = 0;
     mFrameCount = 0;
 
     if (mConsumer.get() == 0) {
         sp<BufferQueue> bq = new BufferQueue();
+
+        int minUndequeuedBuffers = 0;
+        res = bq->query(NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS, &minUndequeuedBuffers);
+        if (res != OK || minUndequeuedBuffers < 0) {
+            ALOGE("%s: Stream %d: Could not query min undequeued buffers (error %d, bufCount %d)",
+                  __FUNCTION__, mId, res, minUndequeuedBuffers);
+            return res;
+        }
+        size_t minBufs = static_cast<size_t>(minUndequeuedBuffers);
+        /*
+         * We promise never to 'acquire' more than camera3_stream::max_buffers
+         * at any one time.
+         *
+         * Boost the number up to meet the minimum required buffer count.
+         *
+         * (Note that this sets consumer-side buffer count only,
+         * and not the sum of producer+consumer side as in other camera streams).
+         */
+        mTotalBufferCount = camera3_stream::max_buffers > minBufs ?
+            camera3_stream::max_buffers : minBufs;
+        // TODO: somehow set the total buffer count when producer connects?
+
         mConsumer = new BufferItemConsumer(bq, camera3_stream::usage,
                                            mTotalBufferCount);
         mConsumer->setName(String8::format("Camera3-InputStream-%d", mId));