Re: [PATCH 2.6.21-rc1] powerpc: Make of_device_uevent() compatible with ibmebus

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Sat, 2007-02-17 at 19:21 -0500, Joachim Fenkes wrote:
> Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote on 17.02.2007 
> 16:56:39:
> 
> > On Sat, 2007-02-17 at 17:28 +0100, Hoang-Nam Nguyen wrote:
> > > ibmebus has a fake root device that's not associated with an ofdt 
> node.
> > > Filter out any such devices in of_device_uevent().
> > 
> > Doh ! You are creating an of_device with no attached device-node ? That
> > is totally evil ! Why do you need that ?
> 
> The driver creates a fake "ibmebus" device so all ibmebus based devices 
> have
> a common parent device -- the vio bus does the same.
> 
> What do you think about linking this device to the device tree "/" node? 
> All
> ibmebus-based devices are linked to dt nodes residing directly beneath 
> "/",
> so the mapping would fit.

No. If you do that, it shouldn't be an of_device based device.

If you want then to be below a common parent, then create that parent of
a basic struct device type, that sort of thing. You should never
instanciate an of_device that has a NULL device node.

vio is different since it's not a "subclass" of of_device though I tend
to also disagree with the way it does things.

It's a generic problem with sysfs, I agree it somewhat sucks.

Ben.