I am getting in a mental pickle regarding LVGL (V9) and NuttX, in
conjunction with the SAMA5D2 with it's built in LCD Controller peripheral.
In the past - bare metal - I have simply set up two buffers so one can
be written to while the other is copied out to the actual display. But
now NuttX is "in the way" ;-)
The NuttX support for V9 LVGL allows you to set it up to use a NuttX LCD
device - but I am pretty sure that us expecting a NuttX device driver
such as /dev/lcd0. The default configuration for the SAMA5 - I believe -
is to create /dev/fb0. I have that device driver registered and it works
- e.g. using the framebuffer example without issue.
I can get LVGL to use /dev/fb0 but the display "tears" and I think that
is because LVGL writes to the same single buffer set up for the SAMA5D2
LCDC, but I can't work out how to get it all to work with 2 buffers. Or
it's for some other reason maybe, but I can't fathom what it might be.
Should I, somehow, convert the framebuffer to a "simpler" driver that
lvgl can work with to create 2 buffers? How?
Or does it need some work at the SAMA5D2 end of things? What?
Or do I need a "custom" lvgl fb interface of some sorts instead? Any
examples?
Thoughts and suggestions would be much appreciated!
Thanks,
Tim
