I set two monitors for imx6 before Multiple monitors, now their display functions work well.
But the touchscreen can move the cursor between two monitors, so I follow Using a touchscreen in a multi-head setup and try to set it.
But I find the screen shown by 'xrandr' is only one as follow:
Screen 0: minimum 240 x 240, current 1024 x 768, maximum 8192 x 8192
DISP3 BG connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
U:1024x768p-59 59.91 +
What's this 'DISP3 BG'? Why there is only one screen?
The GPU is vivante maybe (I see the default xorg.conf is vivante). the latest configuration has uploaded on the last topic above.
Then I try to find the registration of this 'DISP3 BG'. It's on 'drivers/video/fbdev/mxc/mxc_ipuv3_fb.c' (also i find it on 'drivers/media/platform/mxc/capture/mxc_v4l2_capture.c' and 'drivers/video/fbdev/mx3fb.c').
Later I print some graphics information:
root@imx6qsabresd:~# cat /sys/class/graphics/fb*/fsl_disp_dev_property
root@imx6qsabresd:~# cat /sys/class/graphics/fb*/fsl_disp_property
I think maybe the fb2 should be the MEM_BG_SYNC no the MEM_DC_SYNC so that xrandr can detect two screens.
What should I do?
Current xrand is supported however there are some features that are not working well, as example this and the acceleration by GPU, this is marked as a bug.