On Wednesday, September 28, 2016 01:42:20 PM Lukas Wunner wrote: > On Wed, Sep 28, 2016 at 02:33:21AM +0200, Rafael J. Wysocki wrote: > > On Tuesday, September 27, 2016 02:34:29 PM Lukas Wunner wrote: > > > I made some notes while reviewing the state machine in patch 2 of this > > > series and thought, why not rework it into something that could eventually > > > go into the Documentation/ tree? > > > > > > So here's an initial draft. There's some introductory text plus > > > a description of the state machine. Just putting this out there now > > > to ease reviewers' lives, despite the obvious WIP status. I'll try to > > > amend it as the series converges. > > > > > > This is already rst-formatted but I haven't actually run it through > > > sphinx yet. > > > > Thanks a lot for doing this! > > > > It looks good to me in general. I think it would be good to add it to the > > series at one point (if you don't mind). > > Sure thing, thanks. > > > > I'm only a bit reluctant about advertising the usage of links between > > children and parents, because that doesn't look like the right tool for > > the purpose (as I said before, I'd prefer to add a device flag causing > > the parent driver to be probed before the child one if needed). > > That wouldn't cover the unbinding of the child when the parent unbinds > though, so it would only be a subset of the functionality offered by > device links. > > I actually don't know of a use case where driver presence is needed > between parent and child. But the patches look like they should work > out of the box in such a scenario, so I was thinking, why forbid it? > Someone might just try that because they think it should obviously work, > and then they'll find out at runtime that it's forbidden. That gives > us only a score of 5 in Rusty's API rating scheme. > > However for consistency, if you do want to forbid it, I think it should > be forbidden for all ancestors of the device, not just the parent as v3 > does it. (Suspend/resume + shutdown ordering is already handled for > hierarchical dependencies, i.e. all ancestors.)
Well, there is a difference between allowing something to be done and documenting it as a good idea. :-) Thanks, Rafael
