Trucrux Inc

Testing Display

Test Display #

Trucrux IMX8MM provides a MIPI display interface,

To test the display, first check the display node. To check the display node run

root@imx8mm-trux-q01:~# fbset

mode "720x1280"
geometry 720 1280 720 1280 32
timings 0 0 0 0 0 0 0
accel true
rgba 8/16,8/8,8/0,0/0

Graphics are 2D. To test graphics

root@imx8mm-trux-q01: cd /opt/imx-gpu-sdk/GLES2
root@imx8mm-trux-q01: ./GLES<2D graphic file>

Below are the 2D graphics files.

NOTE: The MIPI-DSI Panel used by Trucrux is a Formike “KWH101KQ14-C01” panel with a custom-made driver card.

TouchScreen #

After reboot Search for the below log-in dmesg

input: Goodix Capacitive TouchScreen as /devices/platform/soc@0/soc@0:bus@30800000/30a40000.i2c/i2c-2/2-0014/input/input2

If the above log is available run

root@imx8mm-trux-q01:~# evtest /dev/input/event2

Now touch on the screen you should see the events generated by the touch screen.

Adding Custom MIPI Panel #

NOTE: Trucrux imx8mm provides a MIPI port to connect displays and panels

Adding Driver #

1) Add panel driver file in drivers/gpu/drm/panel/, e.g. panel-custom-lcd.c

2) Add the below command line in drivers/gpu/drm/panel/Makefile to add the driver file in the build process.

obj-$(CONFIG_DRM_PANEL_CUSTOM_LCD) += panel-custom-lcd.o

3) Add the below command line in drivers/gpu/drm/panel/Kconfig to enable and disable the driver from the virtual kernel.

     tristate "Name of custom Panel”
     depends on OF
     depends on DRM_MIPI_DSI
       Say Y if you want to enable support for panels based on the 
       custom panel controller.
Adding node in dtsi file #

1) Open arch/arm64/boot/dts/freescale/imx8mm-trux-8MDVP.dts and navigate to &mipi_dsi node and change the compatible of panel@0 as per custom driver.