音频Codec芯片的时钟

[likangmao]

您好！

当前我们的处理器芯片为i.MX 6Solo/6DualLite双核，音频Codec芯片使用的TAS2505芯片， Codec芯片主时钟信号由CPU引脚GPIO_19/CCM_CLK01提供，芯片驱动加载完成后，用示波器测量发现主时钟信号无输出，设备树的配置如下所示，不知道哪里出了问题，希望得到您的帮助，谢谢！

sound {
compatible = "fsl,imx-audio-tlv320";
model = "imx-tlv320";
ssi-controller = <&ssi1>;
audio-codec = <&codec>;
audio-routing =
"SPK", "Speaker Jack",
"Headphone Jack", "HPOUT";
mux-int-port = <1>;
mux-ext-port = <4>;
codec-master;
};

codec: tas2505@18 {
compatible = "ti,tas2505";
reg = <0x18>;
clocks = <&clks IMX6QDL_CLK_CKO1>;
clock-frequency = <12000000>;
};

&ssi1 {
fsl,mode = "i2s-slave";
status = "okay";
};

&audmux {
status = "okay";
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_audmux>;
};

&iomuxc {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_hog>;

imx6qdl-wisehmi {
pinctrl_hog: hoggrp {
fsl,pins = <
MX6QDL_PAD_GPIO_19__CCM_CLKO1 0x1b0b1
>;
};

pinctrl_audmux: audmuxgrp {
fsl,pins = <
MX6QDL_PAD_CSI0_DAT7__AUD3_RXD 0x130b0
MX6QDL_PAD_CSI0_DAT4__AUD3_TXC 0x130b0
MX6QDL_PAD_CSI0_DAT5__AUD3_TXD 0x110b0
MX6QDL_PAD_CSI0_DAT6__AUD3_TXFS 0x130b0

MX6QDL_PAD_DISP0_DAT23__AUD4_RXD 0x130b0
MX6QDL_PAD_DISP0_DAT20__AUD4_TXC 0x130b0
MX6QDL_PAD_DISP0_DAT21__AUD4_TXD 0x110b0
MX6QDL_PAD_DISP0_DAT22__AUD4_TXFS 0x130b0
>;
};

[weidong_sun]

Hi Kangmao,

   See the code below, please!

codec: tas2505@18 {
compatible = "ti,tas2505";
reg = <0x18>;
clocks = <&clks IMX6QDL_CLK_CKO1>;
clock-frequency = <12000000>;
};

IMX6QDL_CLK_CKO1 should be changed to be "IMX6QDL_CLK_CKO".

try it , please!

Have a nice day!

BR,

weidong

[likangmao]

Mr Wigros Sun:

Sorry!根据您说的，我将codec的clocks由&clks IMX6QDL_CLK_CKO1改为&clks IMX6QDL_CLK_CKO，重新编译烧录后，发现主时钟信号还是无输出，现在呈上原理图及相关驱动代码，烦请帮我分析一下，不胜感激！

[weidong_sun]

hello Kangmao,

   Probably there are 2 ways you will try:

1. Enable and set rate directly in clk-imx6q.c (drivers/clk/imx/clk-imx6q.c).

or

2. play a xxx.wav file on command line, and measure the clock on GPIO_19 pin of CPU

I remember that only when playback begins, the clock will be enabled.

try it , please!

Weidong

[likangmao]

Hi Weidong:

第二种方式我已测试，发现无时钟信号输出， 第一种方式，我不太确定在clk-imx6q.c中如何改动代码，烦请提示一下，谢谢！

[weidong_sun]

Hi Kangmao

you can enable clock in clk-imx6q.c ( drivers/clk/imx/clk-imx6q.c) at first, then measure it to see if it is 12MHz

drivers/clk/imx/clk-imx6q.c

static void __init imx6q_clocks_init(struct device_node *ccm_node)

{

......

                imx_clk_set_parent(clk[IMX6QDL_CLK_CKO2_SEL], clk[IMX6QDL_CLK_OSC]);

                imx_clk_set_parent(clk[IMX6QDL_CLK_CKO], clk[IMX6QDL_CLK_CKO2]);

                clk_set_rate(clk[IMX6QDL_CLK_CKO], 12000000);

                imx_clk_prepare_enable(clk[IMX6QDL_CLK_CKO]);

... ...

}

Have a nice day!

NXP TIC weidong sun

[likangmao]

Hi weidong:

谢谢！我尽快试一下

[likangmao]

Hi WeiDong:

不好意思，按照您上次说的，修改时钟初始化的部分，进行了尝试，音频codec芯片的主时钟信号还是没有12M，不知道问题到底出在哪里了 哭！

[weidong_sun]

Hi kangmao,

   No any signal or no 12MHz?

weidong

[likangmao]

Hi WeiDong:

我用示波器测量了一下，是没有任何信号输出

[weidong_sun]

Hi Kangmao,

   I sent an email to you, giving you a detailed document on how to port audio driver to i.MX6, check it, please!

Have a nice day!

BR,

Weidong