When I started looking into building an image for the Raspberry Pi 2 that supports the new touchscreen I noticed that I couldn’t just use the current release of Yocto named fido. In the fido branch of meta-raspberrypi both the firmware and the kernel is too old to support the new screen, so I had to manually bump those versions in order to get it working. In addition to this I also needed a small addition to config.txt on the boot partition of the sdcard, this addition “dtoverlay=rpi-ft5406” makes sure that an additional device-tree snippet is added to the device-tree passed to the kernel at boot.
The status right now is that qmlscene works well with touch input and the eglfs-backend, I’m not using X11 in my image.
Apparently there are some patches being prepared for the newer kernel to get into meta-raspberrypi, but they’re still not in master. If they don’t become available soon I might just put my modifications into a separate layer for now, along with my adaptations to meta-qt5 and an image recipe. Hopefully I’ll get some time to clean things up and write a how-to post in the coming days, until then feel free to ask questions in the comments.