Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753303AbaAZWcC (ORCPT ); Sun, 26 Jan 2014 17:32:02 -0500 Received: from mail-ig0-f177.google.com ([209.85.213.177]:55582 "EHLO mail-ig0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753054AbaAZWcA (ORCPT ); Sun, 26 Jan 2014 17:32:00 -0500 MIME-Version: 1.0 In-Reply-To: <52E582D0.9070501@gmail.com> 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> Date: Mon, 27 Jan 2014 02:31:59 +0400 Message-ID: Subject: Re: [PATCH] max8925_power: Use "IS_ENABLED(CONFIG_OF)" for DT code. From: Dmitry Eremin-Solenikov To: Tomasz Figa Cc: Dmitry Torokhov , 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 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. -- 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/