I'd have thought that if you want speed, then doing it through any sort of
system call interface is going to be too slow, be it a purpose made system
call, or be it a write() on a special /proc file.
By the way... I'm currently adding such support to my Configuration Manager
and can now read arbitrary ranges of vendor registers from PCI or PnP devices
through the usual mechanism. I'm also intending to add a facility to do the be
able to set arbitrary ranges of registers.
Furthermore, I'm looking at making it possible to have the configuration
'file' open multiple times, thus meaning someone can open it and keep it open
for as long as they wish to use it. I'm also thinking of reinstating the old
ioctl() interface to it.
Watch this space...
David Howells