Re: [PATCH] fix tulip suspend/resume

[Adam Belay <abelay@novell.com>]

On Tue, 2005-06-07 at 14:29 +1000, Benjamin Herrenschmidt wrote:
> > What PM toplevel core changes are you referring to?  I've look over the
> > changes to pm_ops and they seem to make sense.  Still I almost wonder if
> > we should make the entire thing arch specific code, and then have this
> > code call things like device_suspend().  If mac hardware required that
> > many new hooks, then other platforms might require even more.
> 
> That is exactly the debate. Patrick thinks the whole thing should be
> arch code and kernel/power/* just provices "library" routines to call
> (like the freezer, swsusp stuff, etc...), Pavel wants to share as much
> code as possible in a single place.
> 
> I have no real strong preference, I tend to be a bit more on Patrick's
> side here. I can do either way, but we need to decide. On one case, I
> would do a patch removing most of kernel/power/main.c and disk.c (they
> are mostly redundant anyway) and replacing with a simple mecanism where
> the arch provides a table of state names + function to call for sysfs.
> On the other case, just merge my patch adding all the new hooks.
> 
> Ben.

I'd tend to agree with Pat then.  The original pm_ops seem to be
designed around ACPI and after looking at the spec I don't think they're
correct. (e.g. it looks like _PTS and _GTS should be run after
device_suspend() instead of before, so *prepare may not be needed).  In
short, this tends to be tricky.  It's probably best to have platforms
handle it on their own with kernel/power as a library.

Thanks,
Adam