On Wednesday, February 20, 2008 12:29 pm Linus Torvalds wrote: > On Wed, 20 Feb 2008, Rafael J. Wysocki wrote: > > I think we should export the target sleep state somehow. > > Yeah. By *not* using "->suspend()" for freezing or hibernate. > > Please, Rafael - just make the f*cking suspend-to-disk use other routines > already. 99% of all hardware needs to do exactly *nothing* on > suspend-to-disk, and the ones that really do need things tend to need to > not do a whole lot. In talking with Rafael on IRC about this, I think we're agreed that we need separate entry points. Even with a kexec based hibernate, we'll probably want ->hibernate callbacks so we don't end up shutting down the device. The current callback system looks like this (according to Rafael and the last time I looked): ->suspend(PMSG_FREEZE) ->resume() ->suspend(PMSG_SUSPEND) *enter S3 or power off* ->resume() The fact that we get suspend/resume called once before suspend again in the hibernate case is somewhat obnoxious, but it's even worse that we don't know what we're about to enter after ->suspend(PMSG_SUSPEND). So in the short term it would be nice to at least get the target state exported. And in the long term we could have: ->suspend() *enter S3* ->resume() or: ->hibernate() *kexec to another kernel to save image* *power off* ->return_from_hibernate() (or somesuch) Jesse - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
