Keith Packard Sends Out Latest Patches For RandR 1.6, Linux VR Improvements

Keith Packard working under contract for Valve on improving the VR HMD / SteamVR support for the Linux display stack has sent out his latest - near final - patches for the RandR 1.6 additions.

Keith sent out early Friday the latest Resize and Rotate (RandR) X extension updates for dealing with DRM leases and non-desktop output code. The DRM leases is about allowing a "lease" on VR HMD outputs to a VR (SteamVR) compositor.

The non-desktop output code is about ensuring the VR HMD HDMI/DP interface isn't treated as a normal "desktop" output, as is currently the case when using the open-source Radeon driver with the HTC Vive, and ends up becoming part of an extended desktop.

When the HTC Vive is treated as part of the desktop currently with the open-source Radeon Linux driver stack.

From the kernel side, Linux 4.15 introduces the non-desktop quirking and DRM lease infrastructure.

The patches sent out today by Keith deal with the X.Org Server changes and the RandR protocol update.

The work will hopefully land soon as Keith has been planning it to be a key part of X.Org Server 1.20. Originally xorg-server 1.20 was supposed to come in early 2018, but that's looking less and less likely with these patches not yet being merged and the code freeze / release candidates not yet appearing in sight. Thus it's looking risky whether X.Org Server 1.20 with these VR HMD improvements will get picked up by Ubuntu 18.04 LTS.

While the kernel bits are in place and the X.Org bits outstanding, also waiting on the X.Org work to be merged first are the Mesa updates worked on by Keith.

I detailed the overall state of SteamVR on Linux at length just a few days back in SteamVR On Linux Is Still In Frustratingly Rough Shape.