求助：imx6ull SAI2时钟问题

zxcvbnmcg · 发表于 2021-7-6 17:37:48

调试SAI2+WM8960，aplay播放速度是4倍速，示波器查看sai2的mclk是44M，找不到问题在哪里。下面是设备树配置。从/sys/kernel/debug/clk_summry 看到的信息也是12288000.
但是pll4_audio_div是36864000，并不是786432000。

下图是sai2的时钟信息

但是看sai1和sai3是40MHz

以下是设备树的信息。
&clks {
assigned-clocks = <&clks IMX6UL_CLK_PLL4_AUDIO_DIV>;
assigned-clock-rates = <786432000>;
};

sound {
compatible = "simple-audio-card";
simple-audio-card,name = "mx6ul-wm8960";
simple-audio-card,format = "i2s";
simple-audio-card,bitclock-master = <&dailink_master>;
simple-audio-card,frame-master = <&dailink_master>;
simple-audio-card,widgets =
"Microphone", "Mic Jack",
"Line", "Line In",
"Line", "Line Out",
"Speaker", "Speaker",
"Headphone", "Headphone Jack";
simple-audio-card,routing =
"Headphone Jack", "HP_L",
"Headphone Jack", "HP_R",
"Speaker", "SPK_LP",
"Speaker", "SPK_LN",
"Speaker", "SPK_RP",
"Speaker", "SPK_RN",
"LINPUT1", "Mic Jack",
"LINPUT3", "Mic Jack",
"RINPUT1", "Mic Jack",
"RINPUT2", "Mic Jack";

simple-audio-card,cpu {
sound-dai = <&sai2>;
dai-tdm-slot-num = <2>;
};
dailink_master: simple-audio-card,codec {
dai-tdm-slot-num = <2>;
sound-dai = <&codec>;
};

}

codec: wm8960@1a {
#sound-dai-cells = <0>;
compatible = "wlf,wm8960";
reg = <0x1a>;
clocks = <&clks IMX6UL_CLK_SAI2>;
clock-names = "mclk";
wlf,shared-lrclk;
};

&sai2 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_sai2
&pinctrl_sai2_hp_det_b>;

assigned-clocks = <&clks IMX6UL_CLK_SAI2_SEL>,
<&clks IMX6UL_CLK_SAI2>;
assigned-clock-parents = <&clks IMX6UL_CLK_PLL4_AUDIO_DIV>;
assigned-clock-rates = <0>, <12288000>;
// assigned-clock-rates = <0>, <24000000>;
// fsl,sai-synchronous-rx;
fsl,sai-mclk-direction-output;
status = "okay";
};