Re: [PATCH 0/2] external interrupts

[Andrew Morton <akpm@osdl.org>]

Brent Casavant <bcasavan@sgi.com> wrote:
>
> On Sun, 21 Aug 2005, Pavel Machek wrote:
> 
> > > Here is a set of patches that implements an external interrupt capability
> > > in Linux, along with a device driver for a specific hardware device.  I
> > > submitted the patches several weeks ago, and they drew no comments, which
> > > I take to be a good sign.  Anyway, I'm 
> > It was not good sign in this particular case. My reaction was "this is _so_
> > overengineered tjat he's probably joking".
> 
> Laughter was not wholly unexpected, though I wasn't joking.  I'm trying
> to be realistic about the lifetime of any given hardware, and IOC4 is
> several years old at this point.  Couple that with a sincere desire to
> preserve application source compatability when (not if) new hardware
> appears, and an abstraction layer seemed to be a logical choice.  I'm
> more than happy to discuss problems in the abstraction layer's interface
> and make appropriate changes -- I'm nothing if not obliging.

Having an abstraction layer for a single client driver does seem a bit
pointless.  It would become more pointful if other client drivers were to
pop up.

Hence an option would be to merge an IOC4-specific driver which just does
what you need, no abstraction layer.  If someone later comes up with a
requirement for a driver for similar-looking hardware then we can resurrect
the abstraction layer at that stage.