问1：在vpss驱动手册中看到，如果DM8168程序通过HDMI与VGA都能显示，应该怎么做？
通过
cat /sys/devices/platform/vpss/graphics0/nodes
cat /sys/devices/platform/vpss/graphics1/nodes
cat /sys/devices/platform/vpss/graphics2/nodes
看到默认
/dev/fb0 ---hdmi---------display0(Sysfs Name)
/dev/fb1 ---hdcomp-------display3(Sysfs Name)
/dev/fb2 ---sd-----------display2(Sysfs Name)
fb0 默认对应hdmi输出,fb1对应vga输出
VGA的电路引脚连线
AT9---RGB_HS
AP9---RGB_VS
AT21--IOUTA(R)
AR21--IOUTB(G)
AP21--IOUTC(B)
HDMI可以显示图像，为什么VGA没有图像显示呢？
谢谢！
另外如果想关闭的话，不能关闭display0，display1，display3，提示-sh: echo: write error: Invalid argument，请问为什么？
root@HDMTerm:~#
root@HDMTerm:~# echo 0 > /sys/devices/platform/vpss/display0/enabled
-sh: echo: write error: Invalid argument
root@HDMTerm:~# echo 0 > /sys/devices/platform/vpss/display1/enabled
-sh: echo: write error: Invalid argument
root@HDMTerm:~# echo 0 > /sys/devices/platform/vpss/display2/enabled
root@HDMTerm:~# echo 0 > /sys/devices/platform/vpss/display3/enabled
-sh: echo: write error: Invalid argument
root@HDMTerm:~# echo 1 > /sys/devices/platform/vpss/display1/enabled
root@HDMTerm:~# echo 1 > /sys/devices/platform/vpss/display2/enabled
root@HDMTerm:~# echo 1 > /sys/devices/platform/vpss/display3/enabled
root@HDMTerm:~# echo 1 > /sys/devices/platform/vpss/display0/enabled
root@HDMTerm:~# echo 1 > /sys/devices/platform/vpss/display4/enabled
