<#part sign=pgpmime> On Fri, 17 Feb 2012 00:25:51 +0100, Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> wrote: > *** Synchronous pipeline changes *** > > Goal: Create an API to apply complex changes to a video pipeline atomically. > > Needed for complex camera use cases. On the DRM/KMS side, the approach is to > use one big ioctl to configure the whole pipeline. This is the only credible approach for most desktop chips -- you must have the whole configuration available before you can make any commitment to supporting the requested modes. > One solution is a commit ioctl, through the media controller device, that > would be dispatched to entities internally with a prepare step and a commit > step. The current plan for the i915 KMS code is to use a single ioctl -- the application sends a buffer full of configuration commands down to the kernel which can then figure out whether it can be supported or not. The kernel will have to store the intermediate data until the commit arrives anyways, and you still need a central authority in the kernel controlling the final commit decision. -- keith.packard@xxxxxxxxx _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel