Re: Generic events for wake up from S1-S4

["Luis R. Rodriguez" <mcgrof@gmail.com>]

On Sat, Jul 18, 2009 at 3:37 AM, Pavel Machek<pavel@ucw.cz> wrote:
> On Wed 2009-07-15 11:00:07, Luis R. Rodriguez wrote:
>> On Wed, Jul 15, 2009 at 8:51 AM, Luis R. Rodriguez<mcgrof@gmail.com> wrote:
>> > On Tue, Jul 14, 2009 at 4:53 PM, Pavel Machek<pavel@ucw.cz> wrote:
>> >> On Tue 2009-07-14 15:11:45, Luis R. Rodriguez wrote:
>> >>> I'm working on Wake-on-Wireless support for wireless right now [1].
>> >>> Upon wake up I wanted to inform the kernel of the event which caused
>> >>> the wake up but am not clear if there is a generic API for this. Mind
>> >>> you, for WoW we'll need at least some AC power to the card so we'll
>> >>> need to at least be in S3-Hot so we'll only need events for that for
>> >>> now.
>> >>>
>> >>> Do we have some generic infrastructure to gather reasons for wake up
>> >>> from S1-S4 and pass this to userspace yet?
>> >>
>> >> I do not think generic api exists...
>>
>> Going back to this topic -- any suggestions? Will a generic netlink
>> family be OK? Or perhaps easier a udev event for some suitable
>> existing parent ?
>
> Is "who woke me" information even relevant? Yes, it may be interesting
> enough for printk, but... What will userspace do with that information?

Splashy event notification thingies?

I was just trying to avoid verbose debug info for WoW upon wakeup and
figured it be nice to report back through a generic interface.

> Imagine WoW packet comes, 5msec later WoL packet comes, 5msec later
> user opens the lid. You report WoW as wakeup reason, but it is
> inherently "racy".

Hm yeah, but I doubt someone will do that, generally we'd get one wake
up event. Can't we just report the first one and ignore the rest?

> What about simply reporting "wake event happened on this device" and
> doing that for all the devices?

That's fine too. Just think it would be nice to be more specific if possible.

  Luis