完整技术正文依据 RK-KF-YF-320 V1.0.0（8 页）中文原稿。适用表注明所有芯片、所有内核版本、Android 12，属于历史原稿范围，不是当前兼容性承诺。仅有中文来源，没有英文原图；原稿无位图或技术表，所有提交记录、补丁树、配置、调用及日志保留为可编辑文本。封面法律、联络、受众、修订和重复目录移除。未运行示例、应用补丁或测试硬件。
原稿疑点保留：封面日期早于部分 May 2022 提交日期；枚举 PRIMARY=57/SPDIF_1=89 的二进制注释与十进制不符；路径 frameworks/avmedia 缺少通常的目录分隔，正文“3.1”没有对应编号标题。代码/提交哈希和原日期不猜改。灰底中的调用顺序、声卡映射及路径说明已移回正文并完整翻译。补丁为原稿示例片段，含排版折行，不能视为已验证可直接应用的补丁。MultiAudioTest 和 focusChangeHint = 3 会改变应用路由/焦点策略，需针对产品审核，不应直接当量产策略。
背景介绍
Android系统多个AudioTrack同时工作默认混音,即使设备支持多个声卡,没有现成的接口可以使得各声卡同时分别输出不同的声音,系统会按照AudioPolicy中预先设置的策略选择优先级最高的声卡。Android系统虽然定义了多种类型声卡设备,但是如果设备有多个同种类型的声卡(例如,多个HDMI),Android系统现有代码无法对其进行区分。鉴于此,RK开发了一套MultiAudio代码,便于用户合理使用设备声卡,提高用户体验。
RK MultiAudio
MultiAudio能够实现如下功能:多HDMI/DP 插拔识别
PRIMARY/HDMI/SPDIF 声音分离多HDMI OUT:HDMI_0/HDMI_1/…/HDMI_N 声音分离多DP OUT:DP_0/DP_1/…/DP_N 声音分离第三方播放器通过包名指定声卡JAVA层通过接口指定声卡用户可依据自身实际需求合理利用这些功能。
SDK需要包含如下代码
system/media
commit 6c0705147c3f3e80d469096eead9bfd23dee7c69 (HEAD)
Author: shine.liu <shine.liu@rock-chips.com>
Date: Mon Nov 29 10:21:17 2021 +0800
Audio: Add define for hdmi/hdmi_1/spdif/spdif_1
Signed-off-by: shine.liu <shine.liu@rock-chips.com>
Change-Id: I2862278abf20de0e51417564a5e6c15b2b32faed
frameworks/av
commit d239c978d8b4edfbce0dbaad9a89f7460644b0a9 (HEAD)
Author: shine.liu <shine.liu@rock-chips.com>
Date: Wed Apr 27 11:20:27 2022 +0800
MultiAudio: Add route for output of spdif/hdmi/spdif_1/hdmi_1
Signed-off-by: shine.liu <shine.liu@rock-chips.com>
Change-Id: I8c24e894682bdb44243d03d5df4f7acd148d307b
frameworks/base
commit ab4cdd3f83534908b6523d006cf1edc1e33d5396 (HEAD)
Author: shine.liu <shine.liu@rock-chips.com>
Date: Wed Apr 27 10:48:57 2022 +0800
Audio: add multiaudio support for tablet
1. add support for hdmi_1/spdif_1
2. add plug in/out uevent support for hdmi/hdmi_1/spdif/spdif_1
3. fix volume ajust and save
Signed-off-by: shine.liu <shine.liu@rock-chips.com>
Change-Id: I7c09273791fe95c8853c70b9cd22cace424cc28b
device/rockchip/common
commit eb55d8057b2505ba3adc640e65a23d026f1843e3 (HEAD)
Author: shine.liu <shine.liu@rock-chips.com>
Date: Mon Nov 29 10:13:49 2021 +0800
add multiaudio support for tablet
1. audio_policy: separate hdmi and spdif from primary
2. audio_policy: add support for hdmi_1 and spdif_1
3. automake for hdmi/spdif/hdmi_1/spdif_1 hal
Signed-off-by: shine.liu <shine.liu@rock-chips.com>
Change-Id: I8a5c7287d6abf14d90eea2ed6d4e8d762e0a667c
vendor/rockchip/common
commit efacda0a974fad003eb5d9e08de44642c49a7d8f (HEAD)
Author: shine.liu <shine.liu@rock-chips.com>
Date: Thu Apr 28 11:28:49 2022 +0800
vpu: librkmultiaudio: add init version
Signed-off-by: shine.liu <shine.liu@rock-chips.com>
Change-Id: I2d3a4973f964c7c8379fa281dedde7bf7b05f3a9
hardware/interfaces
commit 6d6bdc031705c0560d20bac28ae3cfd758763bc8 (HEAD)
Author: shine.liu <shine.liu@rock-chips.com>
Date: Wed Apr 27 11:15:20 2022 +0800
Audio: Add spdif/hdmi/hdmi_1/spdif_1 in devicefactory
Signed-off-by: shine.liu <shine.liu@rock-chips.com>
Change-Id: I65802c82f85133cd4a10a78149210bba6f7ca986
hardware/rockchip/audio
commit 0ea8e9bb709a7cd576bfe585b60f97b9b250001f (HEAD)
Author: shine.liu <shine.liu@rock-chips.com>
Date: Thu May 12 16:09:57 2022 +0800
[MultiAudio]: Add multiaudio support for tablet sdk
Separating HDMI0/HDMI1/DP0/DP1 to their own hal modules so that they
can work independently at the same time
Signed-off-by: shine.liu <shine.liu@rock-chips.com>
Change-Id: I519802684fb09602954bfdea115a3de891667859
build/make
commit 0a3eb78a77087fffbc3a3e0e45f005661efcf4b1 (HEAD)
Author: shine.liu <shine.liu@rock-chips.com>
Date: Wed May 11 09:58:00 2022 +0800
envsetup: Add BOARD_SUPPORT_MULTIAUDIO env definitions
Signed-off-by: shine.liu <shine.liu@rock-chips.com>
Change-Id: I2adc1b3fc79ff88eb9a4284a4956f1e341c2e7cf
目前代码已合并至RK Android 12 SDK代码,请同步代码并确认以上提交点是否存在。
补丁
如果代码不方便同步更新,请打上如下patch所在目录对应补丁。
➜ patch tree
.
├── build
│ └── make
│ └── 0001-envsetup-Add-BOARD_SUPPORT_MULTIAUDIO-env-definition.patch
├── device
│ └── rockchip
│ └── common
│ └── 0001-add-multiaudio-support-for-tablet.patch
├── frameworks
│ ├── av
│ │ └── 0001-MultiAudio-Add-route-for-output-of-spdif-hdmi-spdif_.patch
│ └── base
│ └── 0001-Audio-add-multiaudio-support-for-tablet.patch
├── hardware
│ ├── interfaces
│ │ └── 0001-Audio-Add-spdif-hdmi-hdmi_1-spdif_1-in-devicefactory.patch
│ └── rockchip
│ └── audio
│ └── 0001-MultiAudio-Add-multiaudio-support-for-tablet-sdk.patch
├── system
│ └── media
│ └── 0001-Audio-Add-define-for-hdmi-hdmi_1-spdif-spdif_1.patch
└── vendor
└── rockchip
└── common
└── 0001-vpu-librkmultiaudio-add-init-version.patch
宏开关
SDK默认支持MultiAudio,如果想关闭或者禁用此功能,可以通过修改BOARD_SUPPORT_MULTIAUDIO来控制。device/rockchip/common
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 0ddef35..858698f 100755
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -412,7 +412,7 @@ BOARD_USER_FAKETOUCH ?= true
endif
ifeq ($(TARGET_BOARD_PLATFORM_PRODUCT), tablet)
-BOARD_SUPPORT_MULTIAUDIO ?= true
+BOARD_SUPPORT_MULTIAUDIO ?= false
endif
#for Camera autofocus support
调用及测试
声卡的选择是通过AudioSessionId来控制的,如下:
typedef enum {
PRIMARY = 57,//1110001
HDMI = 65,//1000001 //hdmi0
SPDIF = 73,//1001001 //dp0
HDMI_1 = 81,//1010001 //hdmi1
SPDIF_1 = 89,//1111001 //dp1
}multi_audio_device_t;
JAVA层通过接口调用
MediaPlayer mp = new MediaPlayer();
mp.setAudioSessionId(audioSessionId);
mp.setDataSource(...);
在 setDataSource 之前调用 setAudioSessionId。输出选择：57 为 speaker，65 为 hdmi，73 为 dp，81 为 hdmi_1，89 为 dp_1。
通过应用包名判断补丁中有测试用例供参考,如需测试,请将frameworks/av下的宏MultiAudioTest打开
diff --git a/media/libaudioclient/include/media/AudioTrack.h
b/media/libaudioclient/include/media/AudioTrack.h
index 53b0be725e..b46a941fe3 100644
--- a/media/libaudioclient/include/media/AudioTrack.h
+++ b/media/libaudioclient/include/media/AudioTrack.h
@@ -35,7 +35,7 @@
#include "android/media/IAudioTrack.h"
#include "android/media/IAudioTrackCallback.h"
-#define MultiAudioTest 0
+#define MultiAudioTest 1
namespace android {
using content::AttributionSourceState;
系统自带RockVideoPlayer和gallery3d,需要再安装一个第三方的mxplayer,并安装多屏显示应用multi-display,补丁包中带这两个应用的安装包。测试用例已经将应用和声卡绑定,实际测试有如下效果:RockVideoPlayer播放视频声音走hdmi声卡gallery3d播放视频声音走hdmi_1声卡mxplayer播放视频声音走speaker声卡并且可以同时播放。
代码实现位置在 frameworks/avmedia/libaudioclient/AudioTrack.cpp，用户可以参考这部分代码依据自身需求修改。
#if MultiAudioTest
String8 tmp = String8(mPackageName);
if (strstr(tmp.string(), "RockVideoPlayer")) {
sessionid = (audio_session_t)65;
} else if (strstr(tmp.string(), "gallery3d")) {
sessionid = (audio_session_t)81;
} else if (strstr(tmp.string(), "mxtech")) {
sessionid = (audio_session_t)57;
}
#endif
通过multi-display将不同的应用投到不同的屏幕,需要设置如下属性,鼠标可以进入不同屏幕控制视频播放。
setprop sys.mouse.presentation 1
另外Android系统有音频焦点功能,多屏多个应用同时播放视频会出现暂停现象,frameworks/base需打上如下补丁:
diff --git
a/services/core/java/com/android/server/audio/MediaFocusControl.java
b/services/core/java/com/android/server/audio/MediaFocusControl.java
index 9548ada14b8e..d82eb3311aeb 100644
--- a/services/core/java/com/android/server/audio/MediaFocusControl.java
+++ b/services/core/java/com/android/server/audio/MediaFocusControl.java
@@ -899,6 +899,7 @@ public class MediaFocusControl implements
PlayerFocusEnforcer {
+ " flags=0x" + Integer.toHexString(flags)
+ " sdk=" + sdk))
.printLog(TAG));
+ focusChangeHint = 3;
// we need a valid binder callback for clients
if (!cb.pingBinder()) {
Log.e(TAG, " AudioFocus DOA client for requestAudioFocus(),
aborting.");
调试
查看声卡
cat proc/asound/cards
rk3588_s:/ # cat proc/asound/cards
0 [rockchipes8388 ]: rockchip-es8388 - rockchip-es8388
rockchip-es8388
1 [rockchiphdmiin ]: rockchip_hdmiin - rockchip,hdmiin
rockchip,hdmiin
2 [rockchiphdmi0 ]: rockchip-hdmi0 - rockchip-hdmi0
rockchip-hdmi0
3 [rockchiphdmi1 ]: rockchip-hdmi1 - rockchip-hdmi1
rockchip-hdmi1
测试驱动是否正常
如果要测试3.1中3588的hdmi0声卡,找一个wav文件,测试命令如下:
tinyplay xxx.wav -D 2 -d 0
如果声音正常,说明hdmi0声卡驱动正常。