From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932961AbcCCXOp (ORCPT ); Thu, 3 Mar 2016 18:14:45 -0500 Received: from mail-wm0-f54.google.com ([74.125.82.54]:36676 "EHLO mail-wm0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758613AbcCCXOm (ORCPT ); Thu, 3 Mar 2016 18:14:42 -0500 From: Eric Auger Subject: Re: [PATCH V14 8/9] vfio, platform: add support for ACPI while detecting the reset driver To: Sinan Kaya , dmaengine@vger.kernel.org, marc.zyngier@arm.com, mark.rutland@arm.com, timur@codeaurora.org, devicetree@vger.kernel.org, cov@codeaurora.org, vinod.koul@intel.com, jcm@redhat.com References: <1454646882-24369-1-git-send-email-okaya@codeaurora.org> <1454646882-24369-9-git-send-email-okaya@codeaurora.org> <56D08843.5020306@linaro.org> <56D7323B.4040100@codeaurora.org> Cc: shankerd@codeaurora.org, vikrams@codeaurora.org, agross@codeaurora.org, arnd@arndb.de, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Message-ID: <56D8C539.9000203@linaro.org> Date: Fri, 4 Mar 2016 00:14:01 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <56D7323B.4040100@codeaurora.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sinan, On 03/02/2016 07:34 PM, Sinan Kaya wrote: > On 2/26/2016 12:15 PM, Eric Auger wrote: >>> -module_init(reset ## _module_init); \ >>>> +#define module_vfio_reset_handler(compat, acpihid, reset) \ >>>> +MODULE_ALIAS("vfio-reset:" compat); \ >> Here you need to handle alias for hid case I think > > I'm wondering what happens when Compat or ACPI string is NULL. > > MODULE_ALIAS("vfio-reset:" NULL) > > Would the kernel like it? > > I'd rather create an alias only when the string is not NULL. Given > this is a macro, I believe it won't work. Indeed I think we should create an alias only for the supported case or 2 aliases if both are supported. > > Can you think of any other way in the code to create the alias? > To be honest I did not find any elegant solution either. Personally I would move the MODULE_ALIAS for compat/acpihid outside of module_vfio_reset_handler macro, directly in the reset module. But maybe someone will propose a better solution? Best Regards Eric