[参考译文] TAS2505：TAS2505 器件在播放 PCM 音频数据时产生噪声。

Other Parts Discussed in Thread: AM62A7

https://e2e.ti.com/support/audio-group/audio/f/audio-forum/1576261/tas2505-the-tas2505-device-produces-noise-when-playing-pcm-audio-data

工具/软件：

SoC：AM62A7

版本 10_00_00_08

clk_mcasp1_fixed: clk_mcasp1_fixed { #clock-cells = <0>; compatible = "fixed-clock"; // clock-frequency = <24576000>; clock-frequency = <12288000>; };
clk_mcasp1: clk_mcasp1 {
#clock-cells = <0>;
// compatible = "gpio-gate-clock";
compatible = "fixed-clock";
clocks = <&clk_mcasp1_fixed>;
//enable-gpios = <&main_gpio1 27 0>; /* BeagleBone Black Clk enable on GPIO1_27 */
};

sound { status = "okay"; compatible = "simple-audio-card"; simple-audio-card,name = "AM62Ax-tas2505"; simple-audio-card,dai-link@0 { format = "i2s"; bitclock-master = <&sound0_master>; frame-master = <&sound0_master>; sound0_master: cpu { sound-dai = <&mcasp1>; system-clock-direction-out; };
codec {
clocks = <&clk_mcasp1>;
sound-dai = <&tas2505>;
};
};
};

main_mcasp1_pins_default: main-mcasp1-default-pins { pinctrl-single,pins = < 
    AM62AX_IOPAD(0x090, PIN_INPUT, 2) /* (L19) GPMC0_BE0n_CLE.MCASP1_ACLKX */ 
    AM62AX_IOPAD(0x098, PIN_INPUT, 2) /* (R18) GPMC0_WAIT0.MCASP1_AFSX */ 
    AM62AX_IOPAD(0x08c, PIN_OUTPUT, 2) /* (K19) GPMC0_WEn.MCASP1_AXR0*/ 
    AM62AX_IOPAD(0x084, PIN_INPUT, 2) /* (L18) GPMC0_ADVn_ALE.MCASP1_AXR2 */ >; 
};

&mcasp1	{ 
    #sound-dai-cells = <0>; 
    pinctrl-names = "default"; 
    pinctrl-0 = <&main_mcasp1_pins_default>; 
    status = "okay"; op-mode = <0>;	/* MCASP_IIS_MODE */ 
    tdm-slots = <2>; 
    serial-dir = <  / 0: INACTIVE, 1: TX, 2: RX / 1 0 2 0 >;
     tx-num-evt = <32>; 
     rx-num-evt = <32>; 
};

根据提供的寄存器、原理图和器件树、有一些可闻噪声会干扰正常的 PCM 音频播放。

PCLK=5.6M MCLK=44.1k