From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Walleij Subject: Re: [PATCH] gpio: palmas: add dt support Date: Tue, 2 Apr 2013 11:01:14 +0200 Message-ID: References: <1363876214-25933-1-git-send-email-ldewangan@nvidia.com> <5153DC24.7040309@nvidia.com> <515459D8.4010001@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: In-Reply-To: <515459D8.4010001-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Stephen Warren Cc: Laxman Dewangan , "grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org" , "rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-tegra@vger.kernel.org On Thu, Mar 28, 2013 at 3:55 PM, Stephen Warren wrote: > On 03/27/2013 11:59 PM, Laxman Dewangan wrote: >> On Wednesday 27 March 2013 06:30 PM, Linus Walleij wrote: >>> On Thu, Mar 21, 2013 at 3:30 PM, Laxman Dewangan >>> wrote: >>> >>>> +#ifdef CONFIG_OF >>>> +static struct of_device_id of_palmas_gpio_match[] = { >>>> + { .compatible = "ti,palmas-gpio"}, >>>> + { }, >>>> +}; >>>> +MODULE_DEVICE_TABLE(of, of_palmas_gpio_match); >>>> +#endif >>> >>> But please drop the #ifdef here unless it causes compile errors >>> (I don't think it will.) >>> >> >> I am using this table as >> >> driver.of_match_table = of_match_ptr(of_palmas_gpio_match), >> of_match_ptr is macro which is NULL in case of CONFIG_OF not defined. >> So if I remove ifdefs then it may create build warning as unused variable. > > I think Linus's point is that you can simply remove the use of > of_match_ptr(). The only disadvantage of doing so is that the table will > always be included in the object file, but it's so small that it's > probably not worth worrying about. Oh I wasn't that smart :-) But what you're saying seems true. The of_match_ptr() is something I haven't quite seen before and don't quite understand the semantics of, why would we use that? Yours, Linus Walleij From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760885Ab3DBJBR (ORCPT ); Tue, 2 Apr 2013 05:01:17 -0400 Received: from mail-ie0-f175.google.com ([209.85.223.175]:50607 "EHLO mail-ie0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760511Ab3DBJBP (ORCPT ); Tue, 2 Apr 2013 05:01:15 -0400 MIME-Version: 1.0 In-Reply-To: <515459D8.4010001@nvidia.com> References: <1363876214-25933-1-git-send-email-ldewangan@nvidia.com> <5153DC24.7040309@nvidia.com> <515459D8.4010001@nvidia.com> Date: Tue, 2 Apr 2013 11:01:14 +0200 Message-ID: Subject: Re: [PATCH] gpio: palmas: add dt support From: Linus Walleij To: Stephen Warren Cc: Laxman Dewangan , "grant.likely@secretlab.ca" , "rob.herring@calxeda.com" , "linux-kernel@vger.kernel.org" , "linux-tegra@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 28, 2013 at 3:55 PM, Stephen Warren wrote: > On 03/27/2013 11:59 PM, Laxman Dewangan wrote: >> On Wednesday 27 March 2013 06:30 PM, Linus Walleij wrote: >>> On Thu, Mar 21, 2013 at 3:30 PM, Laxman Dewangan >>> wrote: >>> >>>> +#ifdef CONFIG_OF >>>> +static struct of_device_id of_palmas_gpio_match[] = { >>>> + { .compatible = "ti,palmas-gpio"}, >>>> + { }, >>>> +}; >>>> +MODULE_DEVICE_TABLE(of, of_palmas_gpio_match); >>>> +#endif >>> >>> But please drop the #ifdef here unless it causes compile errors >>> (I don't think it will.) >>> >> >> I am using this table as >> >> driver.of_match_table = of_match_ptr(of_palmas_gpio_match), >> of_match_ptr is macro which is NULL in case of CONFIG_OF not defined. >> So if I remove ifdefs then it may create build warning as unused variable. > > I think Linus's point is that you can simply remove the use of > of_match_ptr(). The only disadvantage of doing so is that the table will > always be included in the object file, but it's so small that it's > probably not worth worrying about. Oh I wasn't that smart :-) But what you're saying seems true. The of_match_ptr() is something I haven't quite seen before and don't quite understand the semantics of, why would we use that? Yours, Linus Walleij