xref: /aosp_15_r20/frameworks/av/services/audioflinger/datapath/SpdifStreamOut.h (revision ec779b8e0859a360c3d303172224686826e6e0e1)
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_format_t format);
40 
41     status_t open(
42             audio_io_handle_t handle,
43             audio_devices_t devices,
44             struct audio_config *config,
45             audio_output_flags_t *flags,
46             const char *address,
47             const std::vector<playback_track_metadata_v7_t>& sourceMetadata) override;
48 
49     /**
50     * Write audio buffer to driver. Returns number of bytes written, or a
51     * negative status_t. If at least one frame was written successfully prior to the error,
52     * it is suggested that the driver return that successful (short) byte count
53     * and then return an error in the subsequent call.
54     *
55     * If set_callback() has previously been called to enable non-blocking mode
56     * the write() is not allowed to block. It must write only the number of
57     * bytes that currently fit in the driver/hardware buffer and then return
58     * this byte count. If this is less than the requested write size the
59     * callback function must be called when more space is available in the
60     * driver/hardware buffer.
61     */
62     ssize_t write(const void* buffer, size_t bytes) override;
63 
64     /**
65      * @return frame size from the perspective of the application and the AudioFlinger.
66      */
getFrameSize()67     [[nodiscard]] size_t getFrameSize() const override { return sizeof(int8_t); }
68 
69     /**
70      * @return audio_config_base_t from the perspective of the application and the AudioFlinger.
71      */
getAudioProperties()72     [[nodiscard]] audio_config_base_t getAudioProperties() const override {
73         return mApplicationConfig;
74     }
75 
76     /**
77      * @return format from the perspective of the application and the AudioFlinger.
78      */
getFormat()79     [[nodiscard]] virtual audio_format_t getFormat() const { return mApplicationConfig.format; }
80 
81     /**
82      * The HAL may be running at a higher sample rate if, for example, playing wrapped EAC3.
83      * @return sample rate from the perspective of the application and the AudioFlinger.
84      */
getSampleRate()85     [[nodiscard]] virtual uint32_t getSampleRate() const { return mApplicationConfig.sample_rate; }
86 
87     /**
88      * The HAL is in stereo mode when playing multi-channel compressed audio over HDMI.
89      * @return channel mask from the perspective of the application and the AudioFlinger.
90      */
getChannelMask()91     [[nodiscard]] virtual audio_channel_mask_t getChannelMask() const {
92         return mApplicationConfig.channel_mask;
93     }
94 
95     status_t flush() override;
96     status_t standby() override;
97 
98 private:
99 
100     class MySPDIFEncoder : public SPDIFEncoder
101     {
102     public:
MySPDIFEncoder(SpdifStreamOut * spdifStreamOut,audio_format_t format)103         MySPDIFEncoder(SpdifStreamOut *spdifStreamOut, audio_format_t format)
104           :  SPDIFEncoder(format)
105           , mSpdifStreamOut(spdifStreamOut)
106         {
107         }
108 
writeOutput(const void * buffer,size_t bytes)109         ssize_t writeOutput(const void* buffer, size_t bytes) override
110         {
111             return mSpdifStreamOut->writeDataBurst(buffer, bytes);
112         }
113     protected:
114         SpdifStreamOut * const mSpdifStreamOut;
115     };
116 
117     MySPDIFEncoder mSpdifEncoder;
118     audio_config_base_t mApplicationConfig = AUDIO_CONFIG_BASE_INITIALIZER;
119 
120     ssize_t writeDataBurst(const void* data, size_t bytes);
121 
122 #ifdef TEE_SINK
123     NBAIO_Tee mTee;
124 #endif
125 
126 };
127 
128 } // namespace android
129