[PATCH 2/5] Add legacy devices to mpc8641_hpcn.dts

[Segher Boessenkool]

>>>>>> +                          8042 at 60 {
>>>>>> +                                  device_type = "8042";
>>>
>>>> Drop the device_type.  A number as a name isn't
>>>> all that great, either.
>>>
>>>   Yet it's kinda accepted years ago, see:
>>>
>>> http://playground.sun.com/1275/proposals/Closed/Accepted/381-it.txt
>>
>> That's not a published recommendation or anything like that.
>
> But still, it's what got used in what appears to be all ISA based  
> machines
> with such a keyboard controller, both PowerPC and i386 ones.

For PowerPC, I only know about CHRP, which has its own binding
for 8042.  For i386 I think you refer to the OLPC?  It does _not_
comply with this #381 (it has a different unit address text
representation, for one thing).  Also, it has "ps2-interrupt-controller"
in its "compatible" property, which is a much nicer thing to match
drivers on for the OS.

> Are you suggesting that we should declare all existing machines  
> wrong and do
> our own thing instead?

You can read in my words whatever you want, but the only thing
I suggested was what I wrote: drop the device_type.  It is
completely useless in a flat device tree whatever binding you
follow here.

And put something more useful than a bare number in the "compatible"
property.  If you feel you really need to you can _also_ put the
number there, but I think you'll find you don't really want to.

And the "name" should be "keyboard-controller" or something like
that, following the generic names recommended practice.

I would argue the 8042 node shouldn't have a device_type at all
btw, since there is no defined effect of "open"ing this node; but
that is a completely separate discussion.


Segher