Chris Worley wrote: > My video hardware and frame buffer are tightly integrated (a capture > engine that receives decoded video input on the front end of a > non-visible portion of the frame buffer, and an overlay engine that > blends the video and graphics on the back end for output). I think > this tight integration will be used by many cards in the future (video > and graphics cards will be the same, as with the ATI All-In-Wonder, > and Matrox Marvel). > > The frame buffer memory used by the video hardware must be accounted > for and managed from user space, but it should be the V4L driver that > responds with the amount of memory currently required by the video > hardware. > [...] > Should the V4L2 specification be adjusted for this consideration? Or, > how best would this be implemented? This is normally done by creating custom ioctls. These funtions are only used by the X server modules, not the user application, right? And v4l/V4L2 driver and X driver need to be designed and maintained "together" anyway. So just add whatever ioctl functions for the communication between X and the Video for Linux kernel driver you need for your system. Bill.
