imx6solo kernel reset gpio

[1182614726]

大家好，

            目前使用imx6solo芯片，bsp 为 yocto L4.1.15-2.1.10.

            目前发现，在uboot控制的GPIO为高电平，在kernel初始化时，测量会出现一个3ms的低电平。这个gpio是控制背光的pwm，导致logo在显示过渡阶段会出现闪烁。

            请问这是怎么回事呢？是在kernel启动阶段复位了gpio吗？或者有什么办法可以不让kernel复位gpio吗？

            谢谢各位大神鼎力相助。

[Yuri]

Hello,

  Generally the kernel does not change pin states, except those 

pins, that are needed for device (driver) operation. Such initialization 

in implemented in init section of corresponding drivers.

Have a great day,
Yuri

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[1182614726]

Hi Yuri，

            now bsp can display logo from uboot to kernel via lvds. So I want keep the backligt allows on. but now the backlight pwm pin when goes into kernel state，it will use for backlight child-system. because we will to change brightness after QT. So can you help me how to do？

[Yuri]

Hi,

  check Your backlight driver regarding pwm initialization - if it provides the reset.  

~Yuri.

[1182614726]

Hi Yuri,

           Thank you very much! I have remove the brightness update in backlight driver, now the problem has been solved!

            ^_^