Re: [patch 2.6.21-rc5-git] make /proc/acpi/wakeup more useful

David Brownell
2007-04-17T22:00:44Z

On Tuesday 17 April 2007 12:53 pm, David Brownell wrote:
> On Friday 13 April 2007 8:59 am, Pavel Machek wrote:
>
> > ...
> > > Assuming they all adopt that same "parallel tree" model, that seems
> > > like a good idea. The tools will likely need to understand how ACPI
> > > and OF differ, but there's no point in reserving more names than we
> > > really need. Though it may be that "parallel trees" should go away.
> >
> > If mapping is indeed 1-to-1 in acpi... it would be nice to just merge
> > the trees.
>
> Could you elaborate a bit ... what do you mean by "merge"?
>
> One way to merge the trees would be to relocate
>
> /sys/devices/pci* --> ... this *HAS* a PNP node
> /sys/devices/pnp*/X --> /sys/devices/acpi_system*/.../X
>
> Not having the PCI root be its PNPACPI node seems more buglike
> to me than anything else. And for other nodes...

Looks like the i8042 serial nodes will be bizarre too:

/sys/devices/pnp0/00:09
... touchpad's PNP node
/sys/devices/acpi_system:00/device:00/PNP0A03:00/device:15/PNP0F13:00
... its ACPI node
/sys/devices/platform/i8042/serio4
... its serio node

That seems like two nodes too many, but without me trying to twist
my mind around i8042 issues, I can't quite speculate why struct
serio "is-a" device rather than "has-a" device (the PNP node) as
would be the case with a more normal driver structure.

But the existence of that device_add() in serio.c sure explains why
the PNP node doesn't get associated with the input class device one
would expect from knowing that 00:09 is the touchpad.

And hmm, just this morning I saw email from Greg re-affirming that
drivers should not device_add(). Converting such legacy drivers is
simple though, right? :)

- Dave