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1 /*
2  *
3  * Copyright 2015, The Android Open Source Project
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 #pragma once
19 
20 #include <stdint.h>
21 #include <sys/types.h>
22 
23 #include <system/audio.h>
24 
25 #include "AudioStreamOut.h"
26 
27 #include <afutils/NBAIO_Tee.h>
28 #include <audio_utils/spdif/SPDIFEncoder.h>
29 
30 namespace android {
31 
32 /**
33  * Stream that is a PCM data burst in the HAL but looks like an encoded stream
34  * to the AudioFlinger. Wraps encoded data in an SPDIF wrapper per IEC61973-3.
35  */
36 class SpdifStreamOut : public AudioStreamOut {
37 public:
38 
39     SpdifStreamOut(AudioHwDevice *dev, audio_output_flags_t flags,
40             audio_format_t format);
41 
42     status_t open(
43             audio_io_handle_t handle,
44             audio_devices_t devices,
45             struct audio_config *config,
46             const char *address) override;
47 
48     /**
49     * Write audio buffer to driver. Returns number of bytes written, or a
50     * negative status_t. If at least one frame was written successfully prior to the error,
51     * it is suggested that the driver return that successful (short) byte count
52     * and then return an error in the subsequent call.
53     *
54     * If set_callback() has previously been called to enable non-blocking mode
55     * the write() is not allowed to block. It must write only the number of
56     * bytes that currently fit in the driver/hardware buffer and then return
57     * this byte count. If this is less than the requested write size the
58     * callback function must be called when more space is available in the
59     * driver/hardware buffer.
60     */
61     ssize_t write(const void* buffer, size_t bytes) override;
62 
63     /**
64      * @return frame size from the perspective of the application and the AudioFlinger.
65      */
getFrameSize()66     [[nodiscard]] size_t getFrameSize() const override { return sizeof(int8_t); }
67 
68     /**
69      * @return audio_config_base_t from the perspective of the application and the AudioFlinger.
70      */
getAudioProperties()71     [[nodiscard]] audio_config_base_t getAudioProperties() const override {
72         return mApplicationConfig;
73     }
74 
75     /**
76      * @return format from the perspective of the application and the AudioFlinger.
77      */
getFormat()78     [[nodiscard]] virtual audio_format_t getFormat() const { return mApplicationConfig.format; }
79 
80     /**
81      * The HAL may be running at a higher sample rate if, for example, playing wrapped EAC3.
82      * @return sample rate from the perspective of the application and the AudioFlinger.
83      */
getSampleRate()84     [[nodiscard]] virtual uint32_t getSampleRate() const { return mApplicationConfig.sample_rate; }
85 
86     /**
87      * The HAL is in stereo mode when playing multi-channel compressed audio over HDMI.
88      * @return channel mask from the perspective of the application and the AudioFlinger.
89      */
getChannelMask()90     [[nodiscard]] virtual audio_channel_mask_t getChannelMask() const {
91         return mApplicationConfig.channel_mask;
92     }
93 
94     status_t flush() override;
95     status_t standby() override;
96 
97 private:
98 
99     class MySPDIFEncoder : public SPDIFEncoder
100     {
101     public:
MySPDIFEncoder(SpdifStreamOut * spdifStreamOut,audio_format_t format)102         MySPDIFEncoder(SpdifStreamOut *spdifStreamOut, audio_format_t format)
103           :  SPDIFEncoder(format)
104           , mSpdifStreamOut(spdifStreamOut)
105         {
106         }
107 
writeOutput(const void * buffer,size_t bytes)108         ssize_t writeOutput(const void* buffer, size_t bytes) override
109         {
110             return mSpdifStreamOut->writeDataBurst(buffer, bytes);
111         }
112     protected:
113         SpdifStreamOut * const mSpdifStreamOut;
114     };
115 
116     MySPDIFEncoder mSpdifEncoder;
117     audio_config_base_t mApplicationConfig = AUDIO_CONFIG_BASE_INITIALIZER;
118 
119     ssize_t writeDataBurst(const void* data, size_t bytes);
120 
121 #ifdef TEE_SINK
122     NBAIO_Tee mTee;
123 #endif
124 
125 };
126 
127 } // namespace android
128