First Signs Of Wayland Running On Android

A developer for Collabora has been bringing Wayland and the reference Weston compositor to Google's Android mobile Linux platform.

Pekka Paalanen announced the "first light" of Wayland on Android via the wayland-devel mailing list this morning and subsequently blogged about the initial work.

Aside from the first bits of success for Wayland on Android (it's not yet in a usable state for Android), what makes this work even more interesting is that Android has a vastly different graphics stack from the standard Linux desktop. There isn't KMS, DRI, Mesa, or any other common components on Google's Linux platform compared to say Ubuntu or Fedora. The graphics drivers that Pekka had to work with are also closed-source and so he wasn't able to modify the source to the driver to make it work with Wayland, yet he has made progress with Android 4.0 on his Samsung Galaxy Nexus.

While the Android graphics is very different, it's not too different from what's needed by Wayland's Weston compositor. Pekka ended up writing an Android-specific back-end for Weston that can utilize the Android APIs. He's also made workarounds and other changes to make Wayland work on Android's code-base. The blog post goes over in extensive details about this effort.

So far this Wayland/Weston Android back-end only does OpenGL ES 2.0 via EGL for the server, no input device support, and other missing functionality. The "simple-shm" is the only client currently running for now as EGL/GL isn't being exposed to the Wayland clients. There's also Cairo porting and other dependencies that need to be brought to Android.

Right now this work is living in separate Git repositories from mainline Wayland/Weston. "This is the beginning of pushing a Wayland stack into Android. Next I need to clean up, send stuff upstream, add input support, find out about that pageflip, reinvent signal handling and timerfd, and then move on to the second major task: supporting Wayland GL clients. I hope it is possible to implement the Wayland platform in the wrapper-libEGL."

Embedded below is a video by Pekka showing Weston on the Android-powered Samsung phone.

Publicly, Google hasn't expressed any interest in having Wayland on Android. However, Google has been investigating and playing with some code for Wayland on Chrome OS and also ensuring that the Chrome/Chromium web-browser will be well-supported natively on Wayland.