Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> writes: > Hi Arnd, > > On Mon, Nov 24, 2014 at 9:15 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote: >> On Monday 24 November 2014 21:10:05 Geert Uytterhoeven wrote: >>> As this minimal BSC driver isn't hardware-specific at all, I'm wondering >>> if there's a simpler way to do this? >>> - Should the driver be renamed to "simple-bus", and match "simple-bus"? >>> - Should this be moved to core code, without an explicit driver for >>> "simple-bus"? I.e. should the driver core just enable runtime PM for >>> all devices not bound to a driver, as they may represent buses with >>> child devices that do rely on runtime PM? >>> >>> Thanks for your comments and suggestions! >> >> My understanding of simple-bus is that it's something that does >> not have any power-management capabilities, and I'd rather not >> add clocks or interrupts to it. > > OK. > >> What I think makes more sense is to have a bus driver for it >> in drivers/bus, remove the "simple-bus" compatibility value >> and have the driver take care of registering the power domain >> and probing the child devices using of_platform_populate on >> itself. > > Registering power domains is already handled by the core code. > > So compared to my RFC code, I only have to > 1. Drop "simple-bus" from the compatible property in the .dtsi, > 2. Call of_platform_populate() from renesas_bsc_probe(), to > register the child devices, now the core code no longer does that. > > I find it a bit strange having to add _more_ code, as the core code handles > registering child devices fine. Doing it from my bus driver only protects > against people trying to run a kernel without my bus driver included > (which currently works fine, as long as no PM domain or clock is involved, > e.g. if the clock is forgotten in the SoC's .dtsi :-). I actually rather like the simple bus driver in it's current form, where the device and pm-domain registration is taken care of by the core. Since it's really not HW specific at all, maybe just rename it simple-pm-bus or something like that? Kevin -- 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
