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

1 files changed, 131 insertions, 0 deletions

diff --git a/modules/usbcamera/Camera.h b/modules/usbcamera/Camera.h
new file mode 100644
index 0000000..6419c7d
--- /dev/null
+++ b/modules/usbcamera/Camera.h
@@ -0,0 +1,131 @@
+/*
+ * 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 CAMERA_H_
+#define CAMERA_H_
+
+#include <hardware/hardware.h>
+#include <hardware/camera3.h>
+#include <utils/Mutex.h>
+#include <utils/Vector.h>
+#include "Metadata.h"
+#include <sync/sync.h>
+#include "Stream.h"
+
+#define CAMERA_SYNC_TIMEOUT_MS 5000
+
+namespace usb_camera_hal {
+// Camera represents a physical camera on a device.
+// This is constructed when the HAL module is loaded, one per physical camera.
+// It is opened by the framework, and must be closed before it can be opened
+// again.
+// This is an abstract class, containing all logic and data shared between all
+// camera devices.
+class Camera {
+    public:
+        // id is used to distinguish cameras. 0 <= id < NUM_CAMERAS.
+        // module is a handle to the HAL module, used when the device is opened.
+        Camera(int id);
+        virtual ~Camera();
+
+        // Common Camera Device Operations (see <hardware/camera_common.h>)
+        int open(const hw_module_t *module, hw_device_t **device);
+        int getInfo(struct camera_info *info);
+        int close();
+
+        // Camera v3 Device Operations (see <hardware/camera3.h>)
+        int initialize(const camera3_callback_ops_t *callback_ops);
+        int configureStreams(camera3_stream_configuration_t *stream_list);
+        const camera_metadata_t *constructDefaultRequestSettings(int type);
+        int processCaptureRequest(camera3_capture_request_t *request);
+        int flush();
+        void dump(int fd);
+
+        // Update static camera characteristics. This method could be called by
+        // HAL hotplug thread when camera is plugged.
+        void updateInfo();
+
+    protected:
+        // Initialize static camera characteristics.
+        virtual int initStaticInfo() = 0;
+        // Verify settings are valid for a capture
+        virtual bool isValidCaptureSettings(const camera_metadata_t *) = 0;
+        // Separate open method for individual devices
+        virtual int openDevice() = 0;
+        // Separate initialization method for individual devices when opened
+        virtual int initDevice() = 0;
+        // Flush camera pipeline for each individual device
+        virtual int flushDevice() = 0;
+        // Separate close method for individual devices
+        virtual int closeDevice() = 0;
+        // Capture and file an output buffer for an input buffer.
+        virtual int processCaptureBuffer(const camera3_stream_buffer_t *in,
+                camera3_stream_buffer_t *out) = 0;
+        // Accessor method used by initDevice() to set the templates' metadata
+        int setTemplate(int type, camera_metadata_t *settings);
+        // Prettyprint template names
+        const char* templateToString(int type);
+        // Process an output buffer
+
+        // Identifier used by framework to distinguish cameras
+        const int mId;
+        // Metadata containing persistent camera characteristics
+        Metadata mMetadata;
+        // camera_metadata structure containing static characteristics
+        camera_metadata_t *mStaticInfo;
+
+    private:
+        // Camera device handle returned to framework for use
+        camera3_device_t mDevice;
+        // Reuse a stream already created by this device. Must be called with mDeviceLock held.
+        Stream *reuseStreamLocked(camera3_stream_t *astream);
+        // Destroy all streams in a stream array, and the array itself. Must be called with
+        // mDeviceLock held.
+        void destroyStreamsLocked(android::Vector<Stream *> &streams);
+        // Verify a set of streams is valid in aggregate. Must be called with mDeviceLock held.
+        bool isValidStreamSetLocked(const android::Vector<Stream *> &streams);
+        // Calculate usage and max_bufs of each stream. Must be called with mDeviceLock held.
+        void setupStreamsLocked(android::Vector<Stream *> &streams);
+        // Update new settings for re-use and clean up old settings. Must be called with
+        // mDeviceLock held.
+        void updateSettingsLocked(const camera_metadata_t *new_settings);
+        // Send a shutter notify message with start of exposure time
+        void notifyShutter(uint32_t frame_number, uint64_t timestamp);
+        // Is type a valid template type (and valid index into mTemplates)
+        bool isValidTemplateType(int type);
+
+        // Busy flag indicates camera is in use
+        bool mBusy;
+        // Camera device operations handle shared by all devices
+        const static camera3_device_ops_t sOps;
+        // Methods used to call back into the framework
+        const camera3_callback_ops_t *mCallbackOps;
+        // Lock protecting the Camera object for modifications
+        android::Mutex mDeviceLock;
+        // Lock protecting only static camera characteristics, which may
+        // be accessed without the camera device open
+        android::Mutex mStaticInfoLock;
+        // Array of handles to streams currently in use by the device
+        android::Vector<Stream *> mStreams;
+        // Static array of standard camera settings templates
+        camera_metadata_t *mTemplates[CAMERA3_TEMPLATE_COUNT];
+        // Most recent request settings seen, memoized to be reused
+        camera_metadata_t *mSettings;
+        bool mIsInitialized;
+};
+} // namespace usb_camera_hal
+
+#endif // CAMERA_H_