Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753374AbaAZXqb (ORCPT ); Sun, 26 Jan 2014 18:46:31 -0500 Received: from mail-ie0-f177.google.com ([209.85.223.177]:59102 "EHLO mail-ie0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753076AbaAZXq3 (ORCPT ); Sun, 26 Jan 2014 18:46:29 -0500 MIME-Version: 1.0 In-Reply-To: <20140126231452.GE18840@core.coreip.homeip.net> References: <1390720540-13350-1-git-send-email-badarkhe.manish@gmail.com> <52E50C24.8030305@gmail.com> <20140126214542.GC18840@core.coreip.homeip.net> <52E582D0.9070501@gmail.com> <20140126231452.GE18840@core.coreip.homeip.net> Date: Mon, 27 Jan 2014 03:46:28 +0400 Message-ID: Subject: Re: [PATCH] max8925_power: Use "IS_ENABLED(CONFIG_OF)" for DT code. From: Dmitry Eremin-Solenikov To: Dmitry Torokhov Cc: Tomasz Figa , Manish Badarkhe , "linux-samsung-soc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , David Woodhouse 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 Mon, Jan 27, 2014 at 3:14 AM, Dmitry Torokhov wrote: > On Mon, Jan 27, 2014 at 02:31:59AM +0400, Dmitry Eremin-Solenikov wrote: >> On Mon, Jan 27, 2014 at 1:49 AM, Tomasz Figa wrote: >> > On 26.01.2014 22:45, Dmitry Torokhov wrote: >> >> >> >> On Sun, Jan 26, 2014 at 07:31:50PM +0530, Manish Badarkhe wrote: >> >>> >> >>> Hi Tomasz, >> >>> >> >>> Thank you for your review comments. >> >>> >> >>> On Sun, Jan 26, 2014 at 6:52 PM, Tomasz Figa >> >>> wrote: >> >>>> >> >>>> >> >>>> Hi Manish, >> >>>> >> >>>> >> >>>> On 26.01.2014 08:15, Manish Badarkhe wrote: >> >>>>> >> >>>>> >> >>>>> Instead of "#if define CONFIG_OF" use "IS_ENABLED(CONFIG_OF)" >> >>>>> option for DT code to avoid if-deffery in code. >> >>>>> >> >>>>> Signed-off-by: Manish Badarkhe >> >>>>> --- >> >>>>> :100644 100644 b4513f2... d353fbc... M drivers/power/max8925_power.c >> >>>>> drivers/power/max8925_power.c | 14 +++++--------- >> >>>>> 1 file changed, 5 insertions(+), 9 deletions(-) >> >>>>> >> >>>>> diff --git a/drivers/power/max8925_power.c >> >>>>> b/drivers/power/max8925_power.c >> >>>>> index b4513f2..d353fbc 100644 >> >>>>> --- a/drivers/power/max8925_power.c >> >>>>> +++ b/drivers/power/max8925_power.c >> >>>>> @@ -427,7 +427,6 @@ static int max8925_deinit_charger(struct >> >>>>> max8925_power_info *info) >> >>>>> return 0; >> >>>>> } >> >>>>> >> >>>>> -#ifdef CONFIG_OF >> >>>>> static struct max8925_power_pdata * >> >>>>> max8925_power_dt_init(struct platform_device *pdev) >> >>>>> { >> >>>>> @@ -468,13 +467,6 @@ max8925_power_dt_init(struct platform_device >> >>>>> *pdev) >> >>>>> >> >>>>> return pdata; >> >>>>> } >> >>>>> -#else >> >>>>> -static struct max8925_power_pdata * >> >>>>> -max8925_power_dt_init(struct platform_device *pdev) >> >>>>> -{ >> >>>>> - return pdev->dev.platform_data; >> >>>>> -} >> >>>>> -#endif >> >>>>> >> >>>>> static int max8925_power_probe(struct platform_device *pdev) >> >>>>> { >> >>>>> @@ -483,7 +475,11 @@ static int max8925_power_probe(struct >> >>>>> platform_device *pdev) >> >>>>> struct max8925_power_info *info; >> >>>>> int ret; >> >>>>> >> >>>>> - pdata = max8925_power_dt_init(pdev); >> >>>>> + if (IS_ENABLED(CONFIG_OF)) >> >>>>> + pdata = max8925_power_dt_init(pdev); >> >>>>> + else >> >>>>> + pdata = pdev->dev.platform_data; >> >>>>> + >> >>>> >> >>>> >> >>>> >> >>>> This does not look much better than before this patch. Instead of >> >>>> "if-deffery" outside function bodies you are adding "iffery" (if there is >> >>>> such a word) inside a function. >> >>>> What about adding >> >>>> >> >>>> if (!IS_ENABLED(CONFIG_OF)) >> >>>> return pdev->dev.platform_data; >> >>>> >> >>>> on top of max8925_power_dt_init() instead or maybe also renaming this >> >>>> function to max8925_get_pdata()? >> >>> >> >>> >> >>> Okay, I will rename function "max8925_power_dt_init()" to >> >>> "max8925_get_pdata()". >> >>> As you suggested, in the body of this function will add a logic to >> >>> retrieve data in case >> >>> of DT and non-DT platforms. >> >> >> >> >> >> Should we not always favor platform-supplied data regardless of >> >> CONFIG_OF state and fall back to DT (firmware) supplied data if platform >> >> data is absent? This way one can tweak kernel behavior without needing >> >> to change firmware. >> > >> > >> > I guess we should, but apparently this was not the original behavior before >> > this patch, so I'm not sure if we should be squashing such semantic change >> > with this simple refactor. >> >> Hmm. Judging from the code, max8925_power_dt_init() function follows exactly >> opposite strategy - it uses platform_data if of_node is not populated/available. >> So (if dt_init will compile with CONFIG_OF disabled) one can always >> use _dt_init() >> function to retrieve pdata. > > Right, and I question whether this is good behavior or if it should be > corrected. I'd say, correct it. -- With best wishes Dmitry -- 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/