|
From: Gaster, B. <ben...@su...> - 2002-06-18 10:07:06
|
Hello! =20 I have modified the bitkeeper Kyro framebuffer driver to provide additional ioctl calls for the creation of overlay surfaces (to handle YUV to RGB colour conversion). Currently two calls are required for creation of an overlay surface and a creation of viewport (a scaling window mapping the overlay surface on to the RGB output) which returns a pointer to the viewport surface. Currently the pointer returned can only be written to in Kernel space which I assume is due to the pointer into the PCI address space is mapped only in kernel space and not in user space. I presume that it is possible to map the pages to be written by a particular user process but I not sure how to do this and weather it is the best approach.=20 =20 I suppose it would be possible to extend the framebuffer driver to provide an additional driver interface for overlay surfaces and thus use mmap to create a memory mapped region but this seems like over kill for the functionally that I'm after. =20 What do other people think? =20 ben. |