tinydrm

raspbian buster tinydrm (start kernel 4.19.58-y)

Out-of-tree tinydrm modules

Not everyone is able or want to spend time on getting a driver included in Linux, but many can write drivers that works and wants to share it.

This repo is dedicated to the maker community and people that make things work.

First

sudo apt update
sudo apt upgrade
sudo reboot

Install Raspberry Pi Kernel Headers

sudo apt install git bc bison flex libssl-dev libncurses5-dev
sudo apt-get install raspberrypi-kernel-headers

tinydrm

git clone https://github.com/birdtechstep/tinydrm.git
cd tinydrm
make

sudo cp core/tinydrm.ko /lib/modules/`uname -r`/kernel/drivers/gpu/drm/tinydrm/core/
sudo cp mipi-dbi.ko /lib/modules/`uname -r`/kernel/drivers/gpu/drm/tinydrm/
sudo cp ili9488.ko /lib/modules/`uname -r`/kernel/drivers/gpu/drm/tinydrm/
sudo depmod

Dual Display Set

sudo nano /usr/share/X11/xorg.conf.d/99-fbturbo.conf

# This is a minimal sample config file, which can be copied to
# /etc/X11/xorg.conf in order to make the Xorg server pick up
# and load xf86-video-fbturbo driver installed in the system.
#
# When troubleshooting, check /var/log/Xorg.0.log for the debugging
# output and error messages.
#
# Run "man fbturbo" to get additional information about the extra
# configuration options for tuning the driver.

Section "Device"
        Identifier      "Allwinner A10/A13 FBDEV"
        Driver          "fbturbo"
        Option          "fbdev" "/dev/fb0"

        Option          "SwapbuffersWait" "true"
EndSection

Section "Device"
        Identifier      "FBDEV 1"
        Driver          "fbturbo"
        Option          "fbdev" "/dev/fb1"
EndSection

Section "Screen"
        Identifier      "HDMI"
        Device          "Allwinner A10/A13 FBDEV"
        Monitor         "Monitor name 0"
EndSection

Section "Screen"
        Identifier      "TFT LCD"
        Device          "FBDEV 1"
        Monitor         "Monitor name 1"
EndSection

Section "ServerLayout"
        Identifier      "Default Layout"
        Screen          0 "TFT LCD"
        Screen          1 "HDMI" RightOf "TFT LCD"
EndSection

Set Input cell

[ 1 0 0 ]
[ 0 1 0 ]
[ 0 0 1 ]

Option "TransformationMatrix" "c0 0 c1 0 c2 c3 0 0 1"

• c0 = touch_area_width / total_width

• c2 = touch_area_height / total_height

• c1 = touch_area_x_offset / total_width

• c3 = touch_area_y_offset / total_height

Example

X 480/1366+480 = 480/1846 = 0.2600216684723727

Y 320/768 = 320/768 = 0.4166666666666667

X Offset 1366/1846 = 0.7399783315276273

Option "TransformationMatrix" "0.2600216684723727 0 0.7399783315276273 0 0.4166666666666667 0 0 0 1"

sudo nano /usr/share/X11/xorg.conf.d/40-libinput.conf

add Option

Section "InputClass"
        Identifier "libinput touchscreen catchall"
        MatchIsTouchscreen "on"
        MatchDevicePath "/dev/input/event*"
        Driver "libinput"
        Option "TransformationMatrix" "0.2600216684723727 0 0.7399783315276273 0 0.4166666666666667 0 0 0 1"
EndSection

test video on fb1

sudo apt install -y mplayer
wget http://fredrik.hubbe.net/plugger/test.mpg
mplayer -nolirc -vo fbdev2:/dev/fb1 -zoom -x 480 -y 320 test.mpg

BIRD TECHSTEP

Donation

If this project help you reduce time to develop, you can give me a cup of coffee :)