[RK3399][Android7.1] 调试笔记 --- 解决开关按键时产生的Pop声

Platform: RK3399
OS: Android 7.1
Kernel: v4.4.83

背景：

按键音在打开和关闭的时候，会有pop声。

---

原因：

audio codec后面有个功放，功放一直打开着，当codec打开和关闭的时候，会有噪声带进到功放中。

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解决方法：

注：GPIO4_D4是用来控制功放的开关。

diff --git a/arch/arm64/boot/dts/rockchip/rk3399-ecovacs.dts b/arch/arm64/boot/dts/rockchip/rk3399-ecovacs.dts
index 80b31d9..486254b 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-ecovacs.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3399-ecovacs.dts
@@ -651,8 +651,9 @@
 		realtek,in1-differential;
 		pinctrl-names = "default";
 		pinctrl-0 = <&rt5640_hpcon &i2s_8ch_mclk>;
-		hp-con-gpio = <&gpio4 21 GPIO_ACTIVE_HIGH>;
-		//hp-det-gpio = <&gpio4 28 GPIO_ACTIVE_LOW>;
+		//Kris, 181101, Fix pop sound issue.
+		//GPIO4_D4
+		spk-ctl-gpio = <&gpio4 28 GPIO_ACTIVE_LOW>;
 		io-channels = <&saradc 4>;
 		hp-det-adc-value = <500>;
 		status =