On 21.06.21 08:27, Tomohito Esaki wrote: Hi, > Virtual DRM splits the overlay planes of a display controller into multiple > virtual devices to allow each plane to be accessed by each process. > > This makes it possible to overlay images output from multiple processes on a > display. For example, one process displays the camera image without compositor > while another process overlays the UI. Are you attempting to create an simple in-kernel compositor ? I don't think that's not the way to go, at least not by touching each single display driver, and not hardcoding the planes in DT. What's the actual use case you're doing that for ? Why not using some userland compositor ? If you really wanna build a kernel compositor, it should be completely independent of hw drivers. (well, almost - in case of gpus shall be used, the commands obviously need to be dispatched the actual driver) --mtx -- --- Hinweis: unverschlüsselte E-Mails können leicht abgehört und manipuliert werden ! Für eine vertrauliche Kommunikation senden Sie bitte ihren GPG/PGP-Schlüssel zu. --- Enrico Weigelt, metux IT consult Free software and Linux embedded engineering info@xxxxxxxxx -- +49-151-27565287