On Wed, 30 Oct 2013 15:02:40 -0500, Rob Herring <robherring2@xxxxxxxxx> wrote: > On Wed, Oct 30, 2013 at 3:26 AM, Thierry Reding > <thierry.reding@xxxxxxxxx> wrote: > > On Wed, Oct 30, 2013 at 01:12:49AM -0500, Rob Herring wrote: > >> From: Rob Herring <rob.herring@xxxxxxxxxxx> > >> > >> This series adds a couple of boilerplate helpers to match with DT for > >> initcalls and platform device creation and probe. The goal here is to > >> remove more platform code out of arch/arm and eventually the machine > >> descriptors. > > > > I fear that this is a step backwards because it makes it easier for > > people to do the wrong thing. We've been doing the same with interrupt > > controllers and clocks. With those there's at least the argument that > > they need to be available really early and therefore cannot use the > > regular driver model. But for everything else, shouldn't we enforce > > proper drivers to be written? > > You think both are a step backwards or just the initcall one? For > initcalls, there are things which are not drivers, but just one time > init. The example on highbank is highbank_pm_init. In some cases like > cpuidle, they have been converted to platform drivers, but then we > have platform code to create devices if we are on the relevant > platform. There is not really a real device node that exists for some > of these drivers and we need to create the device rather than the > device getting created by scanning the buses in the DT. > > I think this is less error prone because we've had cases of > unconditional initcalls which break multi-platform kernels. In that situation, it would probably be better to simply do what you need to do at initcall level and not register a struct device at all. If the situation is you absolutely need to create a device because the DT does not provide what you need (and the DT cannot be changed) then I strongly recommend separating the driver code and the registration code into separate blocks because it enforces separation between device enumaration and device driver probing. g. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
