The patch [1], which is required for DRM to work properly, has been
merged into Linux version 5.14-rc3. There's a 5.14.12 now in stable, so
I took that one.
After Linux boots, /dev/fb0 will be accessible. You can control the
brightness of the display after enabling the framebuffer by running the
following commands:
~ # echo 0 0 > /sys/class/graphics/fb0/pan
~ # echo 255 >/sys/class/backlight/40016c00.dsi.0/brightness
The brightness ranges from 0 to 255, as you can see running the
command:
~ # cat /sys/class/backlight/40016c00.dsi.0/max_brightness
[1] 24b5b1978cd5 ("clk: stm32f4: fix post divisor setup for I2S/SAI PLLs")
Signed-off-by: Dario Binacchi <dariobin@libero.it>
Acked-by: Christophe Priouzeau <christophe.priouzeau@foss.st.com>
[Arnout: add explanation to readme.txt]
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
830e5227d4