Re: [PATCH 0/4] NE2000 driver updates

Jeff Muizelaar
2003-05-15T02:49:13Z

Adam Belay wrote:

>On Tue, May 13, 2003 at 10:01:12PM -0400, Jeff Muizelaar wrote:
>
>
>
>Hi Jeff,
>
>I agree that an isa interface with sysfs would be useful. This patch looks like
>a great start. I'm considering the following aditional changes...
>
>1.) Perhaps the contents of /drivers/eisa and /drivers/isa should be held in the
>same directory. Comments?
>
Maybe. Though, eisa is still a sane bus, where we get ids and slot
numbers etc. The isa code is pretty much a free for all.

>2.) Some collaboration between isapnp, eisa, and isa would be nice. This is
>because all three of these interfaces could potentially be detecting the same
>devices, resulting in nasty conflicts.
>
Yes, agreed. Probably the easiest way to this is something like an
isa_reserve_(region/resources) that checks if either eisa or pnp know
about anything at the place where we are going to probe. This keeps isa
autoprobe from blindly stealing everything it can get it's hands on, and
lets the higher level buses have priority over it.

This also brings up the question of whether something from eisa/pnp
should also be registered on the isa bus.

>3.) A sysfs interface that would export isa information would be useful.
>
>4.) Perhaps the isa drivers could match against the name of the legacy probing
>driver or maybe the system should be designed to not use device_ids at all.
>
>
Yeah, basically all we need is something that says "this is my device,
give it to me later".

>
>Also a few things to consider...
>
>Is isa limited to one dma, one irq, and one ioport? I haven't seen more then
>this anywere but it would be nice to know for registration purposes.
>
>What is the best action to take if a legacy probing technique detects an area
>that conflicts with a previous legacy probe from another driver. At the very
>least, it would be nice if isa was aware of such things.
>
Right now, it is basically first come, first serve. request_region keeps
people from stepping on each other toes. So, once a driver finds a
region it likes it keeps it and nobody else can touch it. I think it is
probably best to keep it this way.

-Jeff