Re: userspace drivers

[Robert Millan]

On Thu, Feb 06, 2003 at 05:17:18PM +0100, Niels Möller wrote:
> 
> Thinking about L4, I have no idea how ioperm should work, but intwait
> should be fairly easy to implement, it just needs to wait for a
> message from the kernel.

glad to hear. do you think it's pointful to implement it in Mach so we
can use interrupts instead of polling from now on?

i don't know how much resource-consuming is polling from userspace, it worked
for me, but maybe it isn't feasible when it comes to lots of drivers running?

> Besides functions like ioperm and intwait, I guess it would be nice
> with some other more frameworkish things, like managing who can and
> will serve each interrupt, but you don't need any of that until there
> are a dozen or so of different drivers that need to cooperate, so that
> can be an independent project.

are you sure? then i'll start a project next week or so.

> As a final question, are there any parts of the oskit that are useful
> for your driver?

you mean my parport driver? no, this driver is a realy simple thing. no
enhanced modes, etc.. all it does is the barely enough to print text :)

i looked at the parport driver in Linux, but i found it too complicated
(i have no idea on kernel programming, feel much more confortable on
userspace ;)) so just based my work on available specs.

-- 
Robert Millan

"Omnis enim res, quad dando non deficit, dum habetur et non datur,
nondum habetur, quomodo habenda est."

"For if a thing is not diminished by being shared with others, it is
not rightly owned if it is only owned and not shared." 

                Aurelius Augustinus (354-430)