usbcamera: initial implementation of default usb camera HAL

* Basic skeleton of usb camera hal implementation
* Vendor tag is not supported yet
* Further usb camera hal implementation can be filled into UsbCamera.cpp
* Hot plug thread need to be implemented

Change-Id: Ida63b6d640e32192f5b60a280d9d5106d80e523f
diff --git a/modules/usbcamera/Stream.h b/modules/usbcamera/Stream.h
new file mode 100644
index 0000000..022ca9f
--- /dev/null
+++ b/modules/usbcamera/Stream.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef STREAM_H_
+#define STREAM_H_
+
+#include <hardware/camera3.h>
+#include <hardware/gralloc.h>
+#include <system/graphics.h>
+#include <utils/Mutex.h>
+#include <utils/Vector.h>
+
+namespace usb_camera_hal {
+// Stream represents a single input or output stream for a camera device.
+class Stream {
+    public:
+        Stream(int id, camera3_stream_t *s);
+        ~Stream();
+
+        // validate that a stream's parameters match this stream's parameters
+        bool isValidReuseStream(int id, camera3_stream_t *s);
+
+        void setUsage(uint32_t usage);
+        void setMaxBuffers(uint32_t max_buffers);
+
+        int getType();
+        bool isInputType();
+        bool isOutputType();
+        const char* typeToString(int type);
+        const char* formatToString(int format);
+        void dump(int fd);
+
+        // This stream is being reused. Used in stream configuration passes
+        bool mReuse;
+
+    private:
+        // The camera device id this stream belongs to
+        const int mId;
+        // Handle to framework's stream, used as a cookie for buffers
+        camera3_stream_t *mStream;
+        // Array of handles to buffers currently in use by the stream
+        android::Vector<buffer_handle_t *> mBuffers;
+        // Lock protecting the Stream object for modifications
+        android::Mutex mLock;
+};
+} // namespace usb_camera_hal
+
+#endif // STREAM_H_