From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754594Ab0I1NF5 (ORCPT ); Tue, 28 Sep 2010 09:05:57 -0400 Received: from mga01.intel.com ([192.55.52.88]:6580 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753069Ab0I1NF4 (ORCPT ); Tue, 28 Sep 2010 09:05:56 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.57,247,1283756400"; d="scan'208";a="841620498" Date: Tue, 28 Sep 2010 15:06:11 +0200 From: Samuel Ortiz To: Hemanth V Cc: Arun Murthy , lars@metafoo.de, Andrew Morton , kernel@pengutronix.de, philipp.zabel@gmail.com, robert.jarzmik@free.fr, marek.vasut@gmail.com, eric.y.miao@gmail.com, rpurdie@rpsys.net, kgene.kim@samsung.com, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org, STEricsson_nomadik_linux@list.st.com Subject: Re: [PATCH 1/7] pwm: Add pwm core driver Message-ID: <20100928130610.GB20749@sortiz-mobl> References: <1285670134-18063-1-git-send-email-arun.murthy@stericsson.com> <1285670134-18063-2-git-send-email-arun.murthy@stericsson.com> <040c01cb5f0c$29bcb3b0$LocalHost@wipblrx0099946> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <040c01cb5f0c$29bcb3b0$LocalHost@wipblrx0099946> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 28, 2010 at 06:23:24PM +0530, Hemanth V wrote: > ----- Original Message ----- From: "Arun Murthy" > > > > >The existing pwm based led and backlight driver makes use of the > >pwm(include/linux/pwm.h). So all the board specific pwm drivers will > >be exposing the same set of function name as in include/linux/pwm.h. > >As a result build fails in case of multi soc environments where each soc > >has a pwm device in it. > > This seems very specific to ST environment, No it's not. It's an issue Arun has hit while enabling one of the ST MFD chip, but he's tackling a generic issue. > looking at the driver list from > ( [PATCH 4/7] pwm: Align existing pwm drivers with pwm-core ) it seems > most multi SOC environments might support PWM in either one of the SOC. > > arch/arm/plat-mxc/pwm.c > arch/arm/plat-pxa/pwm.c > arch/arm/plat-samsung/pwm.c > arch/mips/jz4740/pwm.c > drivers/mfd/twl6030-pwm.c > > Unless people have examples of other SOCs which might use this, > the better approach might be to go for a custom driver rather than changing > the framework. I wouldn't call the current pwm code a framework. It's a bunch of header definitions that happens to work in the specific case of 1 pwm per sub architecture. What Arun is proposing is an actual framework. And it seems to be clean and simple enough. Cheers, Samuel. -- Intel Open Source Technology Centre http://oss.intel.com/