查看“Soundcard configuration”的源代码

== Overview ==
本文介绍了如何在将ST音频外围设备以及分配给'''Linux® OS'''的外部音频组件以及 [[:Category:Getting_started_with_STM32MP1_boards|STM32MP1 boards]] 时进行配置。 在这种情况下，它们由ALSA框架控制。

在[[ALSA_overview|ALSA framework]]的ASoC层中，音频硬件组件被描述为[[ALSA_overview#Component_descriptions|CPU DAIs and codec]]，它们链接在一起以创建DAI链接。声卡是收集一组DAI链接的软件组件。
以下STM32 MPU板的每个部分都描述了一个或多个声卡。 
提供了每个声卡的示意图，以及其静态和动态配置的方式。

=== Sound card schematic ===

声卡原理图概述了构成声卡的硬件和软件组件及其关系。 

下面给出的示例声卡示意图强调了声卡和设备树部分之间的链接。

[[File:alsa_soundcard_config_overview.png.png|center|link=]]

=== Static configuration ===

* Device tree

设备树允许描述，配置和连接音频硬件组件以定义声卡。用户必须遵循音频图形卡绑定<ref name="Audio graph card bindings">{{CodeSource | Linux kernel | Documentation/devicetree/bindings/sound/audio-graph-card.txt}}</ref> 来配置声卡和设备图绑定<ref name="Device graph bindings">{{CodeSource | Linux kernel | Documentation/devicetree/bindings/graph.txt}}</ref> 来连接音频组件。 用户还必须参考音频组件（编解码器和CPU DAI）绑定，以正确配置这些组件。 音频组件的绑定可以在以下各节的设备树样本中以及[[Soundcard configuration#References|References chapter]]中找到。

STMicroelectronics组态工具 [[STM32CubeMX]], 允许生成CPU DAI设备树节点。 {{Warning|STM32CubeMX不允许配置声卡和编解码器节点，这取决于板。声卡节点和编解码器节点必须通过用户部分手动填充。}}

* asound.conf <ref name="asound.conf">[https://www.alsa-project.org/main/index.php/Asoundrc asound.conf]</ref>
 
可选的asound.conf<ref name="asound.conf"></ref> 系统全局自定义设置文件提供了额外的功能，例如路由和音频样本转换。可以在/ etc目录中找到它。
* 声卡配置文件<ref name="asound.conf"></ref>

alsa-lib层在 /usr/share/alsa/cards 目录中提供卡配置文件。 这些文件允许在标准设备（例如"front", "hdmi" 或 "iec958"设备）上映射ALSA硬件设备。声卡设备树节点中定义的标签定义了卡的名称。 根据 /usr/share/alsa/cards/aliases.conf 映射，从此卡名称中检索卡配置。

=== Dynamic configuration ===

编解码器和CPU DAI驱动程序还提供ALSA控件，允许动态配置声卡。 可以在运行时通过 [[ALSA_overview#How_to_use|amixer]]实用程序更改控件，以修改音频路径中的某些设置。 例如，此类控件可用于修改编解码器中某个块的音频音量或静音状态。

可以使用[[ALSA_overview#How_to_use|alsactl]]实用程序将这些控件的自定义配置保存在asound.state配置文件中。可以在启动时通过[[ALSA_overview#How_to_use|alsactl]]恢复此配置。STM32MPU声卡带有专用的 asound.state 配置文件，可提供相关的控制设置。

== STM32MP15 evaluation board sound card configuration ==

=== Sound card overview ===

{{
ImageMap|
Image:mp15_ev_main_soundcard.png {{!}} frame {{!}} center{{!}} STM32MP15 Evaluation board sound card
rect 187 154 257 202 [[SAI internal peripheral]]
rect 187 252 257 300 [[SAI internal peripheral]]
rect 187 350 257 398 [[SAI internal peripheral]]
rect 187 448 257 496 [[SPDIFRX internal peripheral]]
rect 265 160 386 196 [[SAI Linux driver]]
rect 265 258 386 294 [[SAI Linux driver]]
rect 265 356 386 392 [[SAI Linux driver]]
rect 265 454 386 490 [[SPDIFRX Linux driver]]
rect 448 153 518 201 [[Audio_codecs_hardware_components]]
rect 448 251 518 299 [[Audio_codecs_hardware_components]]
rect 187 546 247 594 [[DFSDM internal peripheral]]
rect 187 742 247 790 [[DFSDM internal peripheral]]
rect 187 840 247 888 [[DFSDM internal peripheral]]
rect 187 644 247 692 [[DFSDM internal peripheral]]
rect 252 552 384 588 [[DFSDM Linux driver]]
rect 252 650 384 686 [[DFSDM Linux driver]]
rect 252 748 384 784 [[DFSDM Linux driver]]
rect 252 847 384 883 [[DFSDM Linux driver]]
rect 448 545 523 593 [[Audio_codecs_hardware_components#ST_MP34DT01-M]]
rect 448 644 523 692 [[Audio_codecs_hardware_components#ST_MP34DT01-M]]
rect 448 741 523 789 [[Audio_codecs_hardware_components#ST_MP34DT01-M]]
rect 448 839 523 887 [[Audio_codecs_hardware_components#ST_MP34DT01-M]]
}}

=== Static configuration ===

以下摘录来自STM32MP15评估板设备树。这里仅显示与声卡关联的节点以及最相关的属性。例如，使用{{green|green}}字体强调链接节点以形成第一个DAI链接的属性。

 / * '''SOUNDCARD''' */
 	sound {
 		compatible = "audio-graph-card<ref name="Audio graph card bindings" />";
 		label = "STM32MP1-EV";			{{highlight|/* Sound card identified as STM32MP1EV in ALSA */}}
 		routing =
 			"AIF1CLK" , "MCLK1",
 			"AIF2CLK" , "MCLK1",
 			"IN1LN" , "MICBIAS2",
 			"DMIC2DAT" , "MICBIAS1",
 			"DMIC1DAT" , "MICBIAS1";
 		dais = <&sai2a_port &sai2b_port &sai4a_port &spdifrx_port
 			&dfsdm0_port &dfsdm1_port &dfsdm2_port &dfsdm3_port>;
 	};
 
 / * '''CODECS''' */
 	spdif_out: spdif-out {
 		compatible = "linux,spdif-dit<ref name="spdif-dit">{{CodeSource | Linux kernel | Documentation/devicetree/bindings/sound/spdif-transmitter.txt}}</ref>";
 
 		spdif_out_port: port@0 {
 			spdif_out_endpoint: endpoint {
 				remote-endpoint = <&sai4a_endpoint>;
 			};
 		};
 	};
 
 	spdif_in: spdif-in {
 		compatible = "linux,spdif-dir<ref name="spdif-dir">{{CodeSource | Linux kernel | Documentation/devicetree/bindings/sound/spdif-receiver.txt}}</ref>";
 		spdif_in_port: port@0 {
 			spdif_in_endpoint: endpoint {
 				remote-endpoint = <&spdifrx_endpoint>;
 			};
 		};
 	};
 
 	dmic0: dmic@0 {
 		compatible = "[[Audio_codecs_hardware_components#ST_MP34DT01-M|dmic-codec]]";
 		port {
 			dmic0_endpoint: endpoint {
 				remote-endpoint = <&dfsdm_endpoint0>;
 			};
 		};
 	};
 
 	dmic1: dmic@1 {
 		compatible = "[[Audio_codecs_hardware_components#ST_MP34DT01-M|dmic-codec]]";
 		port {
 			dmic1_endpoint: endpoint {
 				remote-endpoint = <&dfsdm_endpoint1>;
 			};
 		};
 	};
 
 	dmic2: dmic@2 {
 		compatible = "[[Audio_codecs_hardware_components#ST_MP34DT01-M|dmic-codec]]";
 		port {
 			dmic2_endpoint: endpoint {
 				remote-endpoint = <&dfsdm_endpoint2>;
 			};
 		};
 	};
 
 	dmic3: dmic@3 {
 		compatible = "[[Audio_codecs_hardware_components#ST_MP34DT01-M|dmic-codec]]";
 		port {
 			dmic3_endpoint: endpoint {
 				remote-endpoint = <&dfsdm_endpoint3>;
 			};
 		};
 	};
 };
 
 &i2c2 {
 	wm8994: wm8994@1b {
 		compatible = "[[Audio_codecs_hardware_components#Wolfson_wm8994|wlf,wm8994]]";
 		...
 		clocks = <&sai2a>;
 		clock-names = "MCLK1";
 
 		ports {
 			#address-cells = <1>;
 			#size-cells = <0>;
 
 			<span id="dt_mp15_ev_main_8994_tx_port">{{green|wm8994_tx_port}}</span>: port@0 {
 				wm8994_tx_endpoint: endpoint {
 					remote-endpoint = <&[[#dt_mp15_ev_main_sai2a_ep|{{green|sai2a_endpoint}}]]>;
 				};
 			};
 
 			wm8994_rx_port: port@1 {
 				wm8994_rx_endpoint: endpoint {
 					remote-endpoint = <&sai2b_endpoint>;
 				};
 			};
 		};
 	};
 };
 
 /* '''CPU DAIS''' */
 &sai2 {
 	clocks = <&rcc SAI2>, <&rcc PLL3_Q>, <&rcc PLL4_Q>;
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&sai2a_pins_a>, <&sai2b_pins_a>;
 	pinctrl-1 = <&sai2a_sleep_pins_a>, <&sai2b_sleep_pins_a>;
 	clock-names = "pclk", "x8k", "x11k";
 
 	sai2a: audio-controller@4400b004 {
 		compatible = "[[SAI device tree configuration|st,stm32-sai-sub-a]]";
 		dma-names = "{{highlight|tx}}";				{{highlight|/* SAI set as transmitter */}}
 		clocks = <&rcc SAI2_K>;
 		clock-names = "sai_ck";
 
 		<span id="dt_mp15_ev_main_sai2a_port">{{green|sai2a_port}}</span>: port@0 {
 			<span id="dt_mp15_ev_main_sai2a_ep">{{green|sai2a_endpoint}}: endpoint {
 				remote-endpoint = <&[[#dt_mp15_ev_main_8994_tx_port|{{green|wm8994_tx_endpoint}}]]>;
 				format = "i2s";
 				mclk-fs = {{highlight|<256>}};		{{highlight|/* SAI is master clock provider */}}
 			};
 		};
 	};
 
 	sai2b: audio-controller@4400b024 {
 		compatible = "[[SAI device tree configuration|st,stm32-sai-sub-b]]";
 		dma-names = "{{highlight|rx}}";				{{highlight|/* SAI set as receiver */}}
 		clocks = <&rcc SAI2_K>, <&sai2a>;
 		clock-names = "sai_ck", "MCLK";
 
 		sai2b_port: port@0 {
 			sai2b_endpoint: endpoint {
 				remote-endpoint = <&wm8994_rx_endpoint>;
 				format = "i2s";
 				mclk-fs = {{highlight|<256>}};		{{highlight|/* SAI is master clock provider */}}
 			};
 		};
 	};
 };
 
 &sai4 {
 	clocks = <&rcc SAI4>, <&rcc PLL3_Q>, <&rcc PLL4_Q>;
 	clock-names = "pclk", "x8k", "x11k";
 
 	sai4a: audio-controller@50027004 {
 		compatible = "[[SAI device tree configuration|st,stm32-sai-sub-a]]";
 		dma-names = "tx";
 		{{highlight|st,iec60958}};					{{highlight|/* SAI configured for S/PDIF protocol*/}}
 		pinctrl-names = "default", "sleep";
 		pinctrl-0 = <&sai4a_pins_a>;
 		pinctrl-1 = <&sai4a_sleep_pins_a>;
  		clocks = <&rcc SAI4_K>;
 		clock-names = "sai_ck";
 
 		sai4a_port: port@0 {
 			sai4a_endpoint: endpoint {
 				remote-endpoint = <&spdif_out_endpoint>;
 			};
 		};
 	};
 };
 
 &spdifrx {
  	compatible = "[[SPDIFRX device tree configuration|st,stm32h7-spdifrx]]";
  	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&spdifrx_pins_a>;
 	pinctrl-1 = <&spdifrx_sleep_pins_a>;
 
 	spdifrx_port: port@0 {
 		spdifrx_endpoint: endpoint {
 			remote-endpoint = <&spdif_in_endpoint>;
 		};
 	};
 
 &dfsdm {
 	compatible = "st,stm32mp1-dfsdm";
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&dfsdm_clkout_pins_a
 		     &dfsdm_data1_pins_a &dfsdm_data3_pins_a>;
 	pinctrl-1 = <&dfsdm_clkout_sleep_pins_a
 		     &dfsdm_data1_sleep_pins_a &dfsdm_data3_sleep_pins_a>;
 	spi-max-frequency = <2048000>;
 
 	clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
 	clock-names = "dfsdm", "audio";
  
 	dfsdm0: filter@0 {
 		compatible = "[[DFSDM device tree configuration|st,stm32-dfsdm-dmic]]";
 		st,adc-channels = <{{highlight|3>}}; 	 	 	{{highlight|/* Use channel 3, shared with mic U3 */}}
 		st,adc-channel-names = "{{highlight|dmic_u1}}"; 	{{highlight|/* Left mic U1 associated with Right mic U3, for stereo */}}
 		st,adc-channel-types = "SPI_R"; 	{{highlight|/* Rising edge for left channel */}}
 		st,adc-channel-clk-src = "CLKOUT"; 	{{highlight|/* CKOUT clocks the microphones */}}
 		st,filter-order = <3>;
 
 		asoc_pdm0: dfsdm-dai {
 			compatible = "[[DFSDM device tree configuration|st,stm32h7-dfsdm-dai]]";
 			#sound-dai-cells = <0>;
 			io-channels = <&dfsdm0 0>;
 			cpu_port0: port {
 				dfsdm_endpoint0: endpoint {
 					remote-endpoint = <&dmic0_endpoint>;
 				};
 			};
 		};
 	};
 
 	dfsdm1: filter@1 {
 		compatible = "[[DFSDM device tree configuration|st,stm32-dfsdm-dmic]]";
 		st,adc-channels = <1>;
 		st,adc-channel-names = "dmic_u2";
 		st,adc-channel-types = "SPI_F";
 		st,adc-channel-clk-src = "CLKOUT";
 		st,filter-order = <3>;
 
 		asoc_pdm1: dfsdm-dai {
 			compatible = "[[DFSDM device tree configuration|st,stm32h7-dfsdm-dai]]";
 			#sound-dai-cells = <0>;
 			io-channels = <&dfsdm1 0>;
 			cpu_port1: port {
 				dfsdm_endpoint1: endpoint {
 					remote-endpoint = <&dmic1_endpoint>;
 				};
 			};
 		};
 	};
 
 	dfsdm2: filter@2 {
 		compatible = "[[DFSDM device tree configuration|st,stm32-dfsdm-dmic]]";
 		st,adc-channels = <{{highlight|3}}>; 	 	 	{{highlight|/* Use channel 3, shared with mic U1 */}}
 		st,adc-channel-names = "{{highlight|dmic_u3}}"; 	{{highlight|/* Right mic U3 associated with Left mic U1, for stereo */}}
 		st,adc-channel-types = "SPI_F"; 	{{highlight|/* Falling edge for Right channel */}}
 		st,adc-channel-clk-src = "CLKOUT";
 		st,filter-order = <3>;
 
 		asoc_pdm2: dfsdm-dai {
 			compatible = "[[DFSDM device tree configuration|st,stm32h7-dfsdm-dai]]";
 			#sound-dai-cells = <0>;
 			io-channels = <&dfsdm2 0>;
 			cpu_port2: port {
 				dfsdm_endpoint2: endpoint {
 					remote-endpoint = <&dmic2_endpoint>;
 				};
 			};
 		};
 	};
 
 	dfsdm3: filter@3 {
 		compatible = "[[DFSDM device tree configuration|st,stm32-dfsdm-dmic]]";
 		st,adc-channels = <1>;
 		st,adc-channel-names = "dmic_u4";
 		st,adc-channel-types = "SPI_R";
 		st,adc-channel-clk-src = "CLKOUT";
 		st,filter-order = <3>;
 
 		asoc_pdm3: dfsdm-dai {
 			compatible = "[[DFSDM device tree configuration|st,stm32h7-dfsdm-dai]]";
 			#sound-dai-cells = <0>;
 			io-channels = <&dfsdm3 0>;
 			cpu_port3: port {
 				dfsdm_endpoint3: endpoint {
 					remote-endpoint = <&dmic3_endpoint>;
 				};
 			};
 		};
 	};
 };

用于STMP32MP15评估板的特定于卡的alsa-lib配置文件为/usr/share/alsa/cards/STM32MP1EV.conf。

=== Dynamic configuration ===

下表概述了允许配置STM32MPU评估板“sound”声卡的控件。

{| class="st-table"
! audio device
! CPU DAI
! codec
|-
| playback_codec
| no controls available
| [[#Wolfson wm8994 output configuration|configure codec output path]]
|-
| record_codec
| no controls available
| [[#Wolfson wm8994 input configuration|configure codec input path]]
|-
| playback_spdif
| [[ALSA_overview#IEC_controls|configure iec958]]
| no controls available
|-
| record_spdif
| [[#SPDFIRX input configuration|configure SPDFIRX input path]]
| no controls available
|}

==== Wolfson wm8994 output configuration ====

:在wm8994编解码器上的控制命令，将aif1接口配置为耳机输出（HPOUT1L/R）路径：

<div style="margin-left: 2em;">
 amixer -c STM32MP1EV cset name='AIF1DAC1 Volume' '96' '96'
 amixer -c STM32MP1EV cset name='Headphone Volume' '63' '63'
 amixer -c STM32MP1EV cset name='DAC1 Volume' '50' '50'
 amixer -c STM32MP1EV cset name='DAC1L Mixer AIF1.1 Switch' 'on'
 amixer -c STM32MP1EV cset name='DAC1R Mixer AIF1.1 Switch' 'on'
 amixer -c STM32MP1EV cset name='DAC1 Switch' 'on' 'on'
 amixer -c STM32MP1EV cset name='Left Output Mixer DAC Switch' 'on'
 amixer -c STM32MP1EV cset name='Right Output Mixer DAC Switch' 'on'
 amixer -c STM32MP1EV cset name='Headphone Switch' 'on' 'on'
</div>

:在wm8994编解码器上的控制命令，用于将aif1接口配置为扬声器输出（SPKOUTL/RP）路径：

<div style="margin-left: 2em;">
 amixer -c STM32MP1EV cset name='AIF1DAC1 Volume' '96' '96'
 amixer -c STM32MP1EV cset name='DAC1L Mixer AIF1.1 Switch' 'on'
 amixer -c STM32MP1EV cset name='DAC1R Mixer AIF1.1 Switch' 'on'
 amixer -c STM32MP1EV cset name='DAC1 Switch' 'on','on'
 amixer -c STM32MP1EV cset name='DAC1 Volume' '96','96'
 amixer -c STM32MP1EV cset name='SPKL DAC1 Volume' '50' '50'
 amixer -c STM32MP1EV cset name='SPKR DAC1 Volume' '50' '50'
 amixer -c STM32MP1EV cset name='SPKL DAC1 Switch' 'on'
 amixer -c STM32MP1EV cset name='SPKR DAC1 Switch' 'on'
 amixer -c STM32MP1EV cset name='SPKL Output Switch' 'on'
 amixer -c STM32MP1EV cset name='SPKR Output Switch' 'on'
 amixer -c STM32MP1EV cset name='Speaker Mode' 'Class AB'
 amixer -c STM32MP1EV cset name='Speaker Volume' '50' '50'
 amixer -c STM32MP1EV cset name='Speaker Mixer Volume' 3
 amixer -c STM32MP1EV cset name='Speaker Reference' 0
 amixer -c STM32MP1EV cset name='Speaker Switch' 'on'
</div>

==== Wolfson wm8994 input configuration ====

:在wm8994编解码器上的控制命令，用于将耳机麦克风输入（IN1LN）配置为aif2接口：

<div style="margin-left: 2em;">
 amixer -c STM32MP1EV cset name='IN1L PGA IN1LN Switch' 'on'
 amixer -c STM32MP1EV cset name='IN1L PGA IN1LP Switch' 'off'
 amixer -c STM32MP1EV cset name='IN1L Volume' '25'
 amixer -c STM32MP1EV cset name='IN1L Switch' 'on'
 amixer -c STM32MP1EV cset name='MIXINL IN1L Switch' 'on'
 amixer -c STM32MP1EV cset name='MIXINL IN1L Volume' '1'
 amixer -c STM32MP1EV cset name='MIXINL IN1LP Volume' '0'
 amixer -c STM32MP1EV cset name='AIF1ADCL Source' 'Left'
 amixer -c STM32MP1EV cset name='ADCL Mux' 'ADC'
 amixer -c STM32MP1EV cset name='DAC2 Left Sidetone Volume' '12'
 amixer -c STM32MP1EV cset name='DAC2 Right Sidetone Volume' '12'
 amixer -c STM32MP1EV cset name='AIF2DAC2L Mixer Left Sidetone Switch' 'on'
 amixer -c STM32MP1EV cset name='AIF2DAC2R Mixer Right Sidetone Switch' 'on'
 amixer -c STM32MP1EV cset name='DAC2 Volume' '96' '96'
 amixer -c STM32MP1EV cset name='DAC2 Switch' 'on' 'on'
 amixer -c STM32MP1EV cset name='AIF2ADC Volume' '96' '96'
 amixer -c STM32MP1EV cset name='AIF2ADC Mux' 'AIF2ADCDAT'
 amixer -c STM32MP1EV cset name='AIF2 Boost Volume' '1'
 amixer -c STM32MP1EV cset name='ADC OSR' 'Low Power'
</div>

==== SPDFIRX input configuration ====

:用于在SPDFIRX上配置rx1输入路径的控制命令：

<div style="margin-left: 2em;">
 amixer -c STM32MP1EV cset name='SPDIFRX input' 1
</div>

== STM32MP15 disco board sound card configuration ==

=== Sound card overview ===

{{
ImageMap|
Image:Mp15_dk_main_soundcard.png {{!}} frame {{!}} center{{!}} STM32MP15 Disco 主板声卡
rect 187 154 256 202 [[SAI internal peripheral]]
rect 187 252 256 300 [[SAI internal peripheral]]
rect 187 350 256 398 [[SPI internal peripheral]]
rect 265 160 386 195 [[SAI Linux driver]]
rect 265 258 385 293 [[SAI Linux driver]]
rect 265 356 385 391 [[I2S Linux driver]]
rect 448 153 517 201 [[Audio_codecs_hardware_components]]
rect 448 251 517 299 [[Audio_codecs_hardware_components]]
rect 448 350 517 398 [[Audio_codecs_hardware_components]]
}}

=== Static configuration ===
下面摘录自STM32MP15 DISCO主板设备树。 此处仅显示与声卡关联的节点以及最相关的属性。例如，使用{{green|green}}字体强调链接节点以形成第一DAI链接的属性。
 / {
 / * '''SOUNDCARD''' */
 	sound {
 		compatible = "audio-graph-card";
 		label = "STM32MP1-DK";			{{highlight|/* Sound card identified as STM32MP1DK in ALSA */}}
 		routing =
 			"Playback" , "MCLK",
 			"Capture" , "MCLK",
 			"MICL" , "Mic Bias";
 		dais = <&[[#dt_mp15_dk_main_sai2a_port|{{green|sai2a_port}}]] &sai2b_port &i2s2_port>;
 		status = "okay";
 	};
 };
 
  / * '''CODECS''' */
 &i2c1 {
 	cs42l51: cs42l51@4a {
 		compatible = "[[Audio_codecs_hardware_components#Cirrus_cs42l51|cirrus,cs42l51]]";
 		...
 
 		clocks = <&sai2a>;
 		clock-names = "MCLK";
 
 		cs42l51_port: port {
 			#address-cells = <1>;
 			#size-cells = <0>;
 
 			<span id="dt_mp15_dk_main_cs42l51_tx_endpoint">{{green|cs42l51_tx_endpoint}}</span>: endpoint@0 {
 				reg = <0>;
 				remote-endpoint = <&[[#dt_mp15_dk_main_sai2a_ep|{{green|sai2a_endpoint}}]];
 				frame-master;				{{highlight|/* codec is master */}}
 				bitclock-master;
 			};
 
 			cs42l51_rx_endpoint: endpoint@1 {
 				reg = <1>;
 				remote-endpoint = <&sai2b_endpoint>;
 				frame-master;				{{highlight|/* codec is master */}}
 				bitclock-master;
 			};
 		};
 	};
 
 	hdmi-transmitter@39 {
 		compatible = "[[Audio_codecs_hardware_components#Silab_sil9022|sil,sii9022]]";
 		...
 
 		ports {
 			#address-cells = <1>;
 			#size-cells = <0>;
 
 			port@0 {
 				reg = <0>;
 				sii9022_in: endpoint {
 					remote-endpoint = <&ltdc_ep0_out>;
 				};
 			};
 
 			port@1 {
 				reg = <1>;
 				sii9022_tx_endpoint: endpoint {
 					remote-endpoint = <&i2s2_endpoint>;
 				};
 			};
 		};
 	};
 };
 
 
 
 /* '''CPU DAIS''' */
 &sai2 {
 	clocks = <&rcc SAI2>, <&rcc PLL3_Q>, <&rcc PLL3_Q>;
 	clock-names = "pclk", "x8k", "x11k";
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&sai2a_pins_a>, <&sai2b_pins_b>;
 	pinctrl-1 = <&sai2a_sleep_pins_a>, <&sai2b_sleep_pins_b>;
 	status = "okay";
 
 	sai2a: audio-controller@4400b004 {
 		compatible = "[[SAI device tree configuration|st,stm32-sai-sub-a]]";
 		#clock-cells = <0>;
 		dma-names = "{{highlight|tx}}";				{{highlight|/* SAI set as transmitter */}}
 		clocks = <&rcc SAI2_K>;
 		clock-names = "sai_ck";
 
 		<span id="dt_mp15_dk_main_sai2a_port">{{green|sai2a_port}}</span>: port {
 			<span id="dt_mp15_dk_main_sai2a_ep">{{green|sai2a_endpoint}}: endpoint {
 				remote-endpoint = <&[[#dt_mp15_dk_main_cs42l51_tx_endpoint|{{green|cs42l51_tx_endpoint}}]]>;
 				format = "i2s";
 				mclk-fs = <256>;
 				dai-tdm-slot-num = <2>;
 				dai-tdm-slot-width = <32>;
 			};
 		};
 	};
 
 	sai2b: audio-controller@4400b024 {
 		dma-names = "{{highlight|rx}}";				{{highlight|/* SAI set as receiver */}}
 		st,sync = {{highlight|<&sai2a 2>}};			{{highlight|/* SAI2B is slave of SAI2A */}}
 		clocks = <&rcc SAI2_K>, <&sai2a>;
 		clock-names = "sai_ck", "MCLK";
 
 		sai2b_port: port {
 			sai2b_endpoint: endpoint {
 				remote-endpoint = <&cs42l51_rx_endpoint>;
 				format = "i2s";
 				mclk-fs = <256>;
 				dai-tdm-slot-num = <2>;
 				dai-tdm-slot-width = <32>;
 			};
 		};
 	};
 };
 
 &i2s2 {
 	clocks = <&rcc SPI2>, <&rcc SPI2_K>, <&rcc PLL3_Q>, <&rcc PLL4_Q>;
 	clock-names = "pclk", "i2sclk", "x8k", "x11k";
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&i2s2_pins_a>;
 	pinctrl-1 = <&i2s2_pins_sleep_a>;
 	status = "okay";
 
 	i2s2_port: port {
 		i2s2_endpoint: endpoint {
 			remote-endpoint = <&sii9022_tx_endpoint>;
 			format = "i2s";
 			mclk-fs = <256>;
 		};
 	};
 };

STMP32MP15 Disco板的特定于卡的alsa-lib配置文件为/usr/share/alsa/cards/STM32MP1DK.conf

=== Dynamic configuration ===

The table below gives an overview of the controls allowing the configuration of the STM32MPU disco board sound card.

{| class="st-table"
! audio device
! CPU DAI
! codec
|-
| playback_codec
| no controls available
| [[#Cirrus cs42l51 output configuration|configure codec output path]]
|-
| record_codec
| no controls available
| [[#Cirrus cs42l51 input configuration|configure codec input path]]
|-
| playback_hdmi
| no controls available
| no controls available
|}

==== Cirrus cs42l51 output configuration ====

:Control commands to configure the aif interface to headset output (AOUTA/B) path, on the cs42l51 codec:

<div style="margin-left: 2em;">
 amixer -c STM32MP1DK cset name='PCM Playback Switch' 'on','on'
 amixer -c STM32MP1DK cset name='PCM Playback Volume' '63','63'
 amixer -c STM32MP1DK cset name='Analog Playback Volume' '204','204'
 amixer -c STM32MP1DK cset name='PCM channel mixer' 'L R'
</div>

==== Cirrus cs42l51 input configuration ====

:Control commands to configure headset microphone input (MICIN1/AIN3A) to the aif interface, on the cs42l51 codec:

<div style="margin-left: 2em;">
 amixer -c STM32MP1DK cset name='PGA-ADC Mux Left' '3'
 amixer -c STM32MP1DK cset name='Mic Boost Volume' '1','1'
</div>

== References ==
<references />