A patch for creating a stable user-space driver API has been committed to the Torvalds 2.6 kernel tree
and will appear in the Linux 2.6.23 kernel. This stable user-space driver API will make it possible to write much of a driver in user-space and only a small shell of a driver in the kernel. This user-space driver API depends upon a char device and sysfs to interact with a user-space process to handle interrupts and control memory accesses. Currently this driver API will only work out for simple devices and brings no immediate hope for binary graphics drivers.