In the last couple days I modified the mxsfb.c driver code for the iMX7 to be able to use a LCD display with 8bit serial interface (only 8bits at a time, but three times the speed).
It works so far, but I only get 6bits per color out of the interface. Two bits are always 0, even with Test Images with FF as data. No shifting is active.
Any idea where I could look for the reason?
And one other question. The lcdif driver is one of many that references older imx ICs. In this case imx23 or imx28. Is ther an overview anywhere which compatibilities there are?
Thanks and best regards,
The unit testing for the framebuffer driver concerns the correct boot logo display and examining/setting the framebuffer parameters using fbset utility:
# D: 50.000 MHz, H: 97.656 kHz, V: 319.138 Hz
geometry 320 240 320 480 32
timings 20000 64 64 32 32 64 2
rgba 8/16,8/8,8/0,0/0 <--- please check your current configuration, by default is 8 bits per coloe
The frame buffer driver source code is in drivers/video/mxc/mxsfb.c. The frame buffer driver implementation is abstracted from the actual hardware on i.MX6, not for mx23 or mx28.