1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef CAMERA_H_
18 #define CAMERA_H_
19 
20 #include <hardware/hardware.h>
21 #include <hardware/camera3.h>
22 #include <utils/Mutex.h>
23 #include <utils/Vector.h>
24 #include "Metadata.h"
25 #include <sync/sync.h>
26 #include "Stream.h"
27 
28 #define CAMERA_SYNC_TIMEOUT_MS 5000
29 
30 namespace usb_camera_hal {
31 // Camera represents a physical camera on a device.
32 // This is constructed when the HAL module is loaded, one per physical camera.
33 // It is opened by the framework, and must be closed before it can be opened
34 // again.
35 // This is an abstract class, containing all logic and data shared between all
36 // camera devices.
37 class Camera {
38     public:
39         // id is used to distinguish cameras. 0 <= id < NUM_CAMERAS.
40         // module is a handle to the HAL module, used when the device is opened.
41         explicit Camera(int id);
42         virtual ~Camera();
43 
44         // Common Camera Device Operations (see <hardware/camera_common.h>)
45         int open(const hw_module_t *module, hw_device_t **device);
46         int getInfo(struct camera_info *info);
47         int close();
48 
49         // Camera v3 Device Operations (see <hardware/camera3.h>)
50         int initialize(const camera3_callback_ops_t *callback_ops);
51         int configureStreams(camera3_stream_configuration_t *stream_list);
52         const camera_metadata_t *constructDefaultRequestSettings(int type);
53         int processCaptureRequest(camera3_capture_request_t *request);
54         int flush();
55         void dump(int fd);
56 
57         // Update static camera characteristics. This method could be called by
58         // HAL hotplug thread when camera is plugged.
59         void updateInfo();
60 
61     protected:
62         // Initialize static camera characteristics.
63         virtual int initStaticInfo() = 0;
64         // Verify settings are valid for a capture
65         virtual bool isValidCaptureSettings(const camera_metadata_t *) = 0;
66         // Separate open method for individual devices
67         virtual int openDevice() = 0;
68         // Separate initialization method for individual devices when opened
69         virtual int initDevice() = 0;
70         // Flush camera pipeline for each individual device
71         virtual int flushDevice() = 0;
72         // Separate close method for individual devices
73         virtual int closeDevice() = 0;
74         // Capture and file an output buffer for an input buffer.
75         virtual int processCaptureBuffer(const camera3_stream_buffer_t *in,
76                 camera3_stream_buffer_t *out) = 0;
77         // Accessor method used by initDevice() to set the templates' metadata
78         int setTemplate(int type, camera_metadata_t *settings);
79         // Prettyprint template names
80         const char* templateToString(int type);
81         // Process an output buffer
82 
83         // Identifier used by framework to distinguish cameras
84         const int mId;
85         // Metadata containing persistent camera characteristics
86         Metadata mMetadata;
87         // camera_metadata structure containing static characteristics
88         camera_metadata_t *mStaticInfo;
89 
90     private:
91         // Camera device handle returned to framework for use
92         camera3_device_t mDevice;
93         // Reuse a stream already created by this device. Must be called with mDeviceLock held.
94         Stream *reuseStreamLocked(camera3_stream_t *astream);
95         // Destroy all streams in a stream array, and the array itself. Must be called with
96         // mDeviceLock held.
97         void destroyStreamsLocked(android::Vector<Stream *> &streams);
98         // Verify a set of streams is valid in aggregate. Must be called with mDeviceLock held.
99         bool isValidStreamSetLocked(const android::Vector<Stream *> &streams);
100         // Calculate usage and max_bufs of each stream. Must be called with mDeviceLock held.
101         void setupStreamsLocked(android::Vector<Stream *> &streams);
102         // Update new settings for re-use and clean up old settings. Must be called with
103         // mDeviceLock held.
104         void updateSettingsLocked(const camera_metadata_t *new_settings);
105         // Send a shutter notify message with start of exposure time
106         void notifyShutter(uint32_t frame_number, uint64_t timestamp);
107         // Is type a valid template type (and valid index into mTemplates)
108         bool isValidTemplateType(int type);
109 
110         // Busy flag indicates camera is in use
111         bool mBusy;
112         // Camera device operations handle shared by all devices
113         const static camera3_device_ops_t sOps;
114         // Methods used to call back into the framework
115         const camera3_callback_ops_t *mCallbackOps;
116         // Lock protecting the Camera object for modifications
117         android::Mutex mDeviceLock;
118         // Lock protecting only static camera characteristics, which may
119         // be accessed without the camera device open
120         android::Mutex mStaticInfoLock;
121         // Array of handles to streams currently in use by the device
122         android::Vector<Stream *> mStreams;
123         // Static array of standard camera settings templates
124         camera_metadata_t *mTemplates[CAMERA3_TEMPLATE_COUNT];
125         // Most recent request settings seen, memoized to be reused
126         camera_metadata_t *mSettings;
127         bool mIsInitialized;
128 };
129 } // namespace usb_camera_hal
130 
131 #endif // CAMERA_H_
132