Re: LANANA: To Pending Device Number Registrants

[David Brownell]

> For identifying this is probably the right approach. However identifying is 
> not enough, as the ioctl discussion has shown. Capabilities are needed. How 
> can the device registry provide that information ? 

My feedback on "device registry 0.1" was that I really liked the
approach of _modeling_ devices by attributes ... which reminded me
of the good things in "attribute based naming" a la X.500/LDAP
models.  I suspect 0.2 went too far, using XML to expose those
attributes to userspace ... :)

If each device had a directory node, those directory nodes could be
grouped as a "registry" ... the directory contents would list the various
bus-specific or type-specific capabilities/attributes.  Would those
directory nodes be the /dev/... or /devfs/... nodes?  I suspect not.

>    If we register it together 
> with the device, we might spend a lot of resources needlessly and can't deal 
> with devices whose capabilities change dynamically.

So obviously such a registry should query the drivers/busses directly.

> In addition how do we export the information ? Proc ?

I think Tim has some ideas here, given a patch I scanned recently...

- Dave