Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754507AbaGOAxP (ORCPT ); Mon, 14 Jul 2014 20:53:15 -0400 Received: from mail.active-venture.com ([67.228.131.205]:54221 "EHLO mail.active-venture.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753516AbaGOAxN (ORCPT ); Mon, 14 Jul 2014 20:53:13 -0400 X-Originating-IP: 108.223.40.66 Message-ID: <53C47B76.4080306@roeck-us.net> Date: Mon, 14 Jul 2014 17:53:10 -0700 From: Guenter Roeck User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Chen Gang , Richard Weinberger CC: 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, arnd@arndb.de, Geert Uytterhoeven Subject: Re: [PATCH] drivers: Let several drivers depends on HAS_IOMEM for 'devm_ioremap_resource' References: <201407130545.23004.marex@denx.de> <53C25551.1050909@nod.at> <53C288F0.3070001@metafoo.de> <53C28C4A.70907@nod.at> <53C29015.5070607@metafoo.de> <53C291C8.6050303@nod.at> <53C296C2.30304@metafoo.de> <20140713192202.GA19090@kroah.com> <53C2DF12.6040507@nod.at> <20140713201753.GA29955@kroah.com> <53C39569.9020802@nod.at> <53C3994C.1010309@metafoo.de> <53C39B66.4060500@nod.at> <5A40E1FC-CA61-4AFF-B205-4BAC175AA7AC@gmail.com> <53C47725.8000005@gmail.com> In-Reply-To: <53C47725.8000005@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/14/2014 05:34 PM, Chen Gang wrote: > On 07/14/2014 05:22 PM, Chen Gang wrote: >> >> 在 2014年7月14日，下午4:57，Richard Weinberger 写道： >> >>> Am 14.07.2014 10:48, schrieb Lars-Peter Clausen: >>>> On 07/14/2014 10:31 AM, Richard Weinberger wrote: >>>>> Am 13.07.2014 22:17, schrieb Greg Kroah-Hartman: >>>>>> On Sun, Jul 13, 2014 at 09:33:38PM +0200, Richard Weinberger wrote: >>>>>>> Maybe we could add COMPILE_TEST to the version string too? >>>>>>> Just to detect such kernels fast in user bug reports... >>>>>> >>>>>> What kind of bug report are you going to get? >>>>> >>>>> User manages to enable CONFIG_FOO by selecting COMPILE_TEST and >>>>> complains that it does not work. :) >>>> >>>> These drivers are typically drivers for some SoC peripheral and the device will simply physically not exist on a platform that does not provide HAS_IOMEM. This is not really any >>>> different from making the driver selectable via COMPILE_TEST for any other platform. To hit the issue you'd have to instantiate a device driver instance for a device that >>>> physically does not exist. This will always result in a failure. >>> >>> Okay, you have convinced me. :) >>> > > After search the history patches, I found one related patch which made > by myself (when I am in Asianux): > > "https://lkml.org/lkml/2013/7/1/641" > > For me, it is a long discussion, and forced many members have to join > in. Please help check again. > One thing you could try would be to return NULL (or where appropriate an error) in the #else case of CONFIG_HAS_IOMEM and CONFIG_HAS_IOPORT, ie dont take COMPILE_TEST into account at all. Obviously that means you won't be able to dump a warning message in the COMPILE_TEST case, but at least the code would compile. The rejection of above patch would make a good case for this approach. Guenter -- 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/