Soundcard configuration

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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 STM32MP1 boards 时进行配置。 在这种情况下，它们由ALSA框架控制。

在ALSA framework的ASoC层中，音频硬件组件被描述为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。

Alsa soundcard config overview.png.png

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[1] 来配置声卡和设备图绑定[2] 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References chapter中找到。

STMicroelectronics组态工具 STM32CubeMX, 允许生成CPU DAI设备树节点。

Warning.png 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 [3]

可选的asound.conf[3] 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[3]

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 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

SAI internal peripheral SAI internal peripheral SAI internal peripheral SPDIFRX internal peripheral SAI Linux driver SAI Linux driver SAI Linux driver SPDIFRX Linux driver Audio codecs hardware components Audio codecs hardware components DFSDM internal peripheral DFSDM internal peripheral DFSDM internal peripheral DFSDM internal peripheral DFSDM Linux driver DFSDM Linux driver DFSDM Linux driver DFSDM Linux driver Audio codecs hardware components#ST MP34DT01-M Audio codecs hardware components#ST MP34DT01-M Audio codecs hardware components#ST MP34DT01-M Audio codecs hardware components#ST MP34DT01-M
STM32MP15 Evaluation board sound card

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[1]";
		label = "STM32MP1-EV";			/* 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[4]";

		spdif_out_port: port@0 {
			spdif_out_endpoint: endpoint {
				remote-endpoint = <&sai4a_endpoint>;
			};
		};
	};

	spdif_in: spdif-in {
		compatible = "linux,spdif-dir[5]";
		spdif_in_port: port@0 {
			spdif_in_endpoint: endpoint {
				remote-endpoint = <&spdifrx_endpoint>;
			};
		};
	};

	dmic0: dmic@0 {
		compatible = "dmic-codec";
		port {
			dmic0_endpoint: endpoint {
				remote-endpoint = <&dfsdm_endpoint0>;
			};
		};
	};

	dmic1: dmic@1 {
		compatible = "dmic-codec";
		port {
			dmic1_endpoint: endpoint {
				remote-endpoint = <&dfsdm_endpoint1>;
			};
		};
	};

	dmic2: dmic@2 {
		compatible = "dmic-codec";
		port {
			dmic2_endpoint: endpoint {
				remote-endpoint = <&dfsdm_endpoint2>;
			};
		};
	};

	dmic3: dmic@3 {
		compatible = "dmic-codec";
		port {
			dmic3_endpoint: endpoint {
				remote-endpoint = <&dfsdm_endpoint3>;
			};
		};
	};
};

&i2c2 {
	wm8994: wm8994@1b {
		compatible = "wlf,wm8994";
		...
		clocks = <&sai2a>;
		clock-names = "MCLK1";

		ports {
			#address-cells = <1>;
			#size-cells = <0>;

			wm8994_tx_port: port@0 {
				wm8994_tx_endpoint: endpoint {
					remote-endpoint = <&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 = "st,stm32-sai-sub-a";
		dma-names = "tx";				/* SAI set as transmitter */
		clocks = <&rcc SAI2_K>;
		clock-names = "sai_ck";

		sai2a_port: port@0 {
			sai2a_endpoint: endpoint {
				remote-endpoint = <&wm8994_tx_endpoint>;
				format = "i2s";
				mclk-fs = <256>;		/* SAI is master clock provider */
			};
		};
	};

	sai2b: audio-controller@4400b024 {
		compatible = "st,stm32-sai-sub-b";
		dma-names = "rx";				/* 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 = <256>;		/* 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 = "st,stm32-sai-sub-a";
		dma-names = "tx";
		st,iec60958;					/* 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 = "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 = "st,stm32-dfsdm-dmic";
		st,adc-channels = <3>; 	 	 	/* Use channel 3, shared with mic U3 */
		st,adc-channel-names = "dmic_u1"; 	/* Left mic U1 associated with Right mic U3, for stereo */
		st,adc-channel-types = "SPI_R"; 	/* Rising edge for left channel */
		st,adc-channel-clk-src = "CLKOUT"; 	/* CKOUT clocks the microphones */
		st,filter-order = <3>;

		asoc_pdm0: dfsdm-dai {
			compatible = "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 = "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 = "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 = "st,stm32-dfsdm-dmic";
		st,adc-channels = <3>; 	 	 	/* Use channel 3, shared with mic U1 */
		st,adc-channel-names = "dmic_u3"; 	/* Right mic U3 associated with Left mic U1, for stereo */
		st,adc-channel-types = "SPI_F"; 	/* Falling edge for Right channel */
		st,adc-channel-clk-src = "CLKOUT";
		st,filter-order = <3>;

		asoc_pdm2: dfsdm-dai {
			compatible = "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 = "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 = "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。

audio device CPU DAI codec
playback_codec no controls available configure codec output path
record_codec no controls available configure codec input path
playback_spdif configure iec958 no controls available
record_spdif 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：
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'
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：
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'

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：
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'

SPDFIRX input configuration

用于在SPDFIRX上配置rx1输入路径的控制命令：
amixer -c STM32MP1EV cset name='SPDIFRX input' 1

STM32MP15 disco board sound card configuration

Sound card overview

SAI internal peripheral SAI internal peripheral SPI internal peripheral SAI Linux driver SAI Linux driver I2S Linux driver Audio codecs hardware components Audio codecs hardware components Audio codecs hardware components
STM32MP15 Disco 主板声卡

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";			/* Sound card identified as STM32MP1DK in ALSA */
		routing =
			"Playback" , "MCLK",
			"Capture" , "MCLK",
			"MICL" , "Mic Bias";
		dais = <&sai2a_port &sai2b_port &i2s2_port>;
		status = "okay";
	};
};

 / * CODECS */
&i2c1 {
	cs42l51: cs42l51@4a {
		compatible = "cirrus,cs42l51";
		...

		clocks = <&sai2a>;
		clock-names = "MCLK";

		cs42l51_port: port {
			#address-cells = <1>;
			#size-cells = <0>;

			cs42l51_tx_endpoint: endpoint@0 {
				reg = <0>;
				remote-endpoint = <&sai2a_endpoint;
				frame-master;				/* codec is master */
				bitclock-master;
			};

			cs42l51_rx_endpoint: endpoint@1 {
				reg = <1>;
				remote-endpoint = <&sai2b_endpoint>;
				frame-master;				/* codec is master */
				bitclock-master;
			};
		};
	};

	hdmi-transmitter@39 {
		compatible = "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 = "st,stm32-sai-sub-a";
		#clock-cells = <0>;
		dma-names = "tx";				/* SAI set as transmitter */
		clocks = <&rcc SAI2_K>;
		clock-names = "sai_ck";

		sai2a_port: port {
			sai2a_endpoint: endpoint {
				remote-endpoint = <&cs42l51_tx_endpoint>;
				format = "i2s";
				mclk-fs = <256>;
				dai-tdm-slot-num = <2>;
				dai-tdm-slot-width = <32>;
			};
		};
	};

	sai2b: audio-controller@4400b024 {
		dma-names = "rx";				/* SAI set as receiver */
		st,sync = <&sai2a 2>;			/* 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

下表概述了允许配置STM32MPU DISCO主板声卡的控件。

audio device CPU DAI codec
playback_codec no controls available configure codec output path
record_codec no controls available configure codec input path
playback_hdmi no controls available no controls available

Cirrus cs42l51 output configuration

控制命令，用于在cs42l51编解码器上将aif接口配置为耳机输出（AOUTA / B）路径：
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'

Cirrus cs42l51 input configuration

控制命令，用于在cs42l51编解码器上将耳机麦克风输入（MICIN1 / AIN3A）配置到aif接口：
amixer -c STM32MP1DK cset name='PGA-ADC Mux Left' '3'
amixer -c STM32MP1DK cset name='Mic Boost Volume' '1','1'

References

  1. ↑ 1.01.1 Documentation/devicetree/bindings/sound/audio-graph-card.txt| |}} Documentation/devicetree/bindings/sound/audio-graph-card.txt
  2. ↑ Documentation/devicetree/bindings/graph.txt| |}} Documentation/devicetree/bindings/graph.txt
  3. ↑ 3.03.13.2 asound.conf
  4. ↑ Documentation/devicetree/bindings/sound/spdif-transmitter.txt| |}} Documentation/devicetree/bindings/sound/spdif-transmitter.txt
  5. ↑ Documentation/devicetree/bindings/sound/spdif-receiver.txt| |}} Documentation/devicetree/bindings/sound/spdif-receiver.txt
取自“http://wiki.100ask.org/index.php?title=Soundcard_configuration&oldid=7453”