Android HDMI dual display using allwinner A20 - linux-kernel

we developed out custom android for our own board developed by our company. Initially I am having issues in displaying similar content on hdmi but i solved that issue . Now we are trying to display different content on hdmi but
/sys/devices/virtual/disp/disp/hdmi status is showing 0 (HDMI not Connected !)
while we are having similar display on hdmi port. We are using android 4.2. I need guidance, where to look in the android code or do i have to change my driver for hdmi ( because i am using driver for marsboard A20) ?
Thanks.

First of you need to see in product fex file that whether HDMI support is enable in your device or not.
You will find product fex file in lichee/tools/pack/chips/sun7i/config/android//sys_config.fex.
Check values of screen0_output_type and screen1_output_type attributes.

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http://www.nrgsoft.com/blog/?p=11
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