AnsweredAssumed Answered

Regarding i.MX6DQ display blanking/unblanking with L3.0.101.

Question asked by Satoshi Shimoda on Oct 16, 2015
Latest reply on Oct 19, 2015 by Qiang Li - Mpu Se

Hi community,


I have some questions about i.MX6DQ Linux BSP (L3.0.101) frame buffer.



You know /dev/fb0 is unblanked when i.MX6DQ Linux BSP (L3.0.101_4.1.1) is boot, but /dev/fb2 is blanked if fb0=ldb and fb2=hdmi.

(with 'video=mxcfb0:dev=ldb video=mxcfb1:dev=hdmi,1920x1080M@60,if=RGB' boot parameter)

Then, we want to be unblanked both display (lvds and hdmi) when boot i.MX6DQ Linux BSP, not only /dev/fb0.

I checked Dual display LVDS + HDMI on iMX6 , but it seems to has been unresolved.

So what should we modify to realize it?

Change a device driver? or a boot parameter?



We can unblank a hdmi display with the following command.

  echo 0 > /sys/class/graphics/fb2/blank

After unblanking both display (/dev/fb0:lvds, /dev/fb2:hdmi) by the above command, I executed the following command.

  echo 1 > /sys/class/graphics/fb0/blank

Then, not only fb2 (hdmi display) was blanked but also fb0 (lvds display).

How should we do to blank only fb2 in this case?



Best Regards,

Satoshi Shimoda