diff --git a/source/linux/Foundational_Components/Graphics/Common/QT_Graphics_Framework.rst b/source/linux/Foundational_Components/Graphics/Common/QT_Graphics_Framework.rst index c0cb4df27..ad6023d89 100644 --- a/source/linux/Foundational_Components/Graphics/Common/QT_Graphics_Framework.rst +++ b/source/linux/Foundational_Components/Graphics/Common/QT_Graphics_Framework.rst @@ -31,6 +31,14 @@ provided with Qt. By default EGLFS will use the ``eglfs_kms`` backend. The default ``eglfs_kms`` configuration file for Qt5 is located at :file:`/etc/qt5/eglfs_kms_cfg.json`. +Please note that EGLFS backend is not smart enough to select a display device +automatically. One must be specified in the config file using the ``device`` +key. If one is not specified, :file:`/dev/dri/card0` will be used, which can +either point at the GPU or the Display device depending on the order in which +the devices were initialized. We recommend using the :file:`/dev/dri/by-path/*` +path for a persistent device path. If an incorrect device was chosen, an error +like the following can appear: ``Failed to create display device (err=19)``. + For more information about Qt's EGLFS and using Qt5 in embedded applications see: