Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754633AbaKDQBM (ORCPT ); Tue, 4 Nov 2014 11:01:12 -0500 Received: from mail-wi0-f182.google.com ([209.85.212.182]:64048 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754164AbaKDQBJ (ORCPT ); Tue, 4 Nov 2014 11:01:09 -0500 From: Grant Likely Subject: Re: [PATCH 0/1] Compact interface for Device-Tree To: Arnd Bergmann , "Rafael J. Wysocki" Cc: Rob Herring , Gilad Avidov , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Sagar Dharia , linux-arm-msm , David Woodhouse In-Reply-To: <40803956.DTL7dD7CLv@wuerfel> References: <1414709964-27284-1-git-send-email-gavidov@codeaurora.org> <7637604.7PK9W8ePf3@vostro.rjw.lan> <40803956.DTL7dD7CLv@wuerfel> Date: Tue, 04 Nov 2014 15:53:29 +0000 Message-Id: <20141104155329.A23A5C423D0@trevor.secretlab.ca> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 03 Nov 2014 16:06:03 +0100 , Arnd Bergmann wrote: > On Friday 31 October 2014 23:53:28 Rafael J. Wysocki wrote: > > On Saturday, November 01, 2014 05:13:45 AM Rob Herring wrote: > > > On Fri, Oct 31, 2014 at 6:59 AM, Gilad Avidov wrote: > > > > > > > > Device-Tree compact API > > > > ------------------------ > > > > > > > > Common code seen in driver’s probe reads device tree values and handling > > > > erroneous return codes from all those of_property_read_xxx() APIs. This > > > > common code is factored out by the of_property_map module which allows > > > > driver’s probe to replace that (often lengthy) code with a concise table: > > > > > > > > struct of_prop_map map[] = { > > > > {"i2c", &dev->id, OF_REQ, OF_ID, -1}, > > > > {"qcom,clk-freq-out", &dev->clk_freq_out, OF_REQ, OF_U32, 0}, > > > > {"qcom,clk-freq-in", &dev->clk_freq_in, OF_REQ, OF_U32, 0}, > > > > {"qcom,disable-dma", &dev->disable_dma, OF_OPT, OF_BOOL, 0}, > > > > {"qcom,master-id", &dev->mstr_id, OF_SGST, OF_U32, 0}, > > > > {NULL, NULL, 0, 0, 0}, > > > > }; > > > > > > > > Then call populate to read the values into the device’s variables: > > > > > > > > ret = of_prop_populate(dev, dev->of_node, map); > > > > > > Interesting idea. The main concern I have with this is there has been > > > on-going discussions about how to generalize property handling across > > > DT and ACPI to make drivers more agnostic, so I'm copying a few folks > > > involved in that. That may be a bit orthogonal to what this is doing, > > > but we may want some coordination here. > > > > Agreed. > > > > We actually have a patchset adding a unified device property API in > > linux-next (http://git.kernel.org/cgit/linux/kernel/git/rafael/linux-pm.git/log/?h=device-properties) > > and I'd prefer to see the "compactization" to happen at that level, if possible, > > rather that for of_ only. > > Agreed, this should definitely use the new generalized API. > I have prototyped a similar concept last year, which actually went much > further and also abstracted high-level properties such as interrupts, > gpios, pwm, dma-engine, etc. I still think we should do something > like that, but I've never had the time to follow up and nobody else > picked up my work from back then. > > Would others like to see that? Absolutely. I also tried to do the same thing and didn't get very far. And, yes, it should be done at the level of the device properties API. g. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/