From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olof Johansson Subject: Re: [RFC PATCH dtc] C-based DT schema checker integrated into dtc Date: Mon, 4 Nov 2013 10:57:36 -0800 Message-ID: References: <1382651488-9696-1-git-send-email-swarren@wwwdotorg.org> <1432962.yW4lKnaQJE@flatron> <25161583.XICaeMWvPh@flatron> <2443024.JdDKnfkC18@wuerfel> <5277CD33.6030003@wwwdotorg.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: In-Reply-To: <5277CD33.6030003-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Stephen Warren Cc: Arnd Bergmann , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , Tomasz Figa , Mark Rutland , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Jon Loeliger , Kevin Hilman , Stephen Warren , Benoit Cousson , Pawel Moll , Tomasz Figa , Rob Herring , Grant Likely , fparent-rdvid1DuHRBWk0Htik3J/w@public.gmane.org, a.hajda-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, Sylwester Nawrocki , Kumar Gala , Alison_Chaiken-nmGgyN9QBj3QT0dZR+AlfA@public.gmane.org, David Gibson List-Id: devicetree@vger.kernel.org On Mon, Nov 4, 2013 at 8:37 AM, Stephen Warren wrote: > I had suggested that while talking to someone at the kernel summit, > basically each driver supplies functions like: > > 1) ACPI -> platform data or resources converter > 2) DT -> platform or resources data converter > 3) anything else -> platform or resources data converter > 4) probe() > > One of (1)..(3) (depending on device instantiation source) is called to > translate the data source to platform data or resources, before probe > (and could indeed handle much of deferred probe I suppose). > > (4) is called to actually initialize the device, and always has complete > pre-parsed platform data/resources available, and does no DT/ACPI/... > parsing. > > I forget who I was talking to, but it was asserted something like this > had been proposed before, and wasn't accepted. Unfortunately, I don't > entirely recall why... > > It may have been due to the fact I proposed (1) and (2) above being > separate, rather than identical, due to using some unified API to read > data from ACPI and DT. That wasn't the most interesting aspect of the > proposal though. Still, I think conceptually there could be other data > sources in the future, so we may need to allow different types of > conversion function at some point, even if the ACPI and DT > implementations can end up being the same. I think it might have been me you were talking to. I know Grant considered something like that when first doing the device tree enablement, and chose not to do it then but I am not sure what the motivations were. Given that we have cleaned up a lot of driver probing already by now, it might be suitable to try again. -Olof -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html