Re: [RFC PATCH v10 6/7] PCI / PM: Move acpi wakeup code to pci core

[Brian Norris]

On Wed, Dec 06, 2017 at 04:17:54PM -0800, Tony Lindgren wrote:
> * Brian Norris <briannorris@xxxxxxxxxxxx> [171206 19:36]:
> > By the way, it seems pretty ambiguous how we want to handle things like
> > (a) multiple devices sharing the same WAKE#
> > (b) systems where a slot is swappable
> > 
> > For (a), the main problem is that if we have to repeat the interrupt
> > definition in multiple devices, then we have to deal with something like
> > IRQF_SHARED. That can be done, but it makes it much harder to use the
> > dedicated wakeirq helpers.
> 
> This will get messy, let's not go there :) That is unless the hardware
> really has a single interrupt wired to multiple devices. And in that
> case almost certainly a custom interrupt handler is needed.

As Rafael mentioned, the spec doesn't clearly delineate a required
hierarchy to the WAKE# pin, and it's certainly possible to share it. I'm
fine dodging that question for now, and only writing said custom
interrupt handler if/when needed.

But device tree bindings are "forever", so it seems reasonable to at
least agree how it should be defined.

Brian