meta-digi-dey provides the lvgl-demo_9.3.0.bb recipe for the LVGL example included in the dey-image-lvgl image.
This recipe uses the lv-conf.inc file, which handles logic associated with LVGL’s driver configurations.
Both of these files abstract the LVGL demo, allowing you to change some of its parameters via the Yocto configuration without having to modify the C sources directly.
Change LVGL back-end
You can select the LVGL rendering back-end in your conf/local.conf file via the LVGL_BACKEND variable, which can be set to:
-
wayland(default), recommended for environments with the XWayland desktop back-end. -
fbdev, which renders the application directly to the system’s framebuffer.
For example, the following line configures the demo to use the fbdev back-end:
LVGL_BACKEND = "fbdev"
Build the firmware
After changing the parameters, you can build a full image or a software update package.
Digi Embedded Yocto provides two recipes to build firmware with the LVGL demo:
-
The dey-image-lvgl.bb recipe creates the images with the demo.
$ bitbake dey-image-lvgl -
The dey-image-lvgl-swu.bb recipe generates the corresponding software update package.
$ bitbake dey-image-lvgl-swu
You can use these recipes or your own to create your firmware. To develop your own apps using LVGL, see Develop your own LVGL applications.