Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756185AbaGQJ3p (ORCPT ); Thu, 17 Jul 2014 05:29:45 -0400 Received: from mail-pa0-f41.google.com ([209.85.220.41]:37289 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755515AbaGQJ3m (ORCPT ); Thu, 17 Jul 2014 05:29:42 -0400 Message-ID: <53C7977B.9090903@gmail.com> Date: Thu, 17 Jul 2014 17:29:31 +0800 From: Chen Gang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Arnd Bergmann CC: Guenter Roeck , Richard Weinberger , Lars-Peter Clausen , Greg Kroah-Hartman , dmitry.torokhov@gmail.com, linux-iio@vger.kernel.org, Benjamin Herrenschmidt , teg@jklm.no, Thierry Reding , Lennox Wu , Marek Vasut , Liqin Chen , msalter@redhat.com, linux-pwm@vger.kernel.org, devel@driverdev.osuosl.org, linux-watchdog@vger.kernel.org, linux-input@vger.kernel.org, "linux-kernel@vger.kernel.org" , knaack.h@gmx.de, Martin Schwidefsky , Mischa.Jonker@synopsys.com, jic23@kernel.org, Geert Uytterhoeven Subject: Re: [PATCH] drivers: Let several drivers depends on HAS_IOMEM for 'devm_ioremap_resource' References: <201407130545.23004.marex@denx.de> <53C53CE1.4090803@gmail.com> <53C7269E.4010702@gmail.com> <6823014.2plXDE9VA9@wuerfel> In-Reply-To: <6823014.2plXDE9VA9@wuerfel> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/17/2014 05:20 PM, Arnd Bergmann wrote: > On Thursday 17 July 2014 09:27:58 Chen Gang wrote: >> gfp_t gfp_mask, unsigned int order); >> extern void devm_free_pages(struct device *dev, unsigned long addr); >> >> +#ifdef CONFIG_HAS_IOMEM >> void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res); >> +#elif defined(CONFIG_COMPILE_TEST) >> +static inline void __iomem *devm_ioremap_resource(struct device *dev, >> + struct resource *res) >> +{ >> + pr_warn("no hardware io memory, only for COMPILE_TEST\n"); >> + return (__force void __iomem *)ERR_PTR(-ENXIO); >> +} >> +#endif /* CONFIG_HAS_IOMEM || CONFIG_COMPILE_TEST */ >> >> /* allows to add/remove a custom action to devres stack */ > > To be honest, I think it's a bad idea to introduce wrappers functions > that are only available when CONFIG_COMPILE_TEST is set. > > COMPILE_TEST is a great tool in general, but it has its limits. > In particular, the case for !CONFIG_IOMEM is completely obscure > and we won't find any bugs by allowing more drivers to be built > in those configurations, but attempting to do it would cause > endless churn by changing each instance of 'depends on HAS_IOMEM' > to 'depends on HAS_IOMEM || COMPILE_TEST'. > Architecture members and driver members really have different tastes, they are different roles. It really need additional discussion. For me, I only want to change devm_io*map*, not touch so much. Welcome any other members' idea or suggestions. > Note that s390 no has gained support for IOMEM, tile has it most > of the time (when PCI is enabled, so you get it in half the > test builds already), score should set HAS_IOMEM and doesn't > even have public compilers, and uml doesn't even compile in > latest mainline. Nothing else ever sets NO_IOMEM. > In latest gcc and binutils, can compile score cross compiler successfully for building kernel (but I am not quite sure whether the compiling result are really OK, but I guess so). And next (maybe after finish allmodconfig for microblaze), I shall try to let uml pass allmodconfig for linux-next tree. Thanks. -- Chen Gang Open, share, and attitude like air, water, and life which God blessed -- 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/