From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1754152AbdGUJpj (ORCPT <rfc822;w@1wt.eu>);
        Fri, 21 Jul 2017 05:45:39 -0400
Received: from lelnx193.ext.ti.com ([198.47.27.77]:29973 "EHLO
        lelnx193.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1753679AbdGUJpi (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Fri, 21 Jul 2017 05:45:38 -0400
Subject: Re: [PATCH 03/12] ARM: normalize clk API for older platforms
To: Arnd Bergmann <arnd@arndb.de>
CC: Kevin Hilman <khilman@kernel.org>,
        Hartley Sweeten <hsweeten@visionengravers.com>,
        Alexander Sverdlin <alexander.sverdlin@gmail.com>,
        Eric Miao <eric.y.miao@gmail.com>,
        Haojian Zhuang <haojian.zhuang@gmail.com>,
        Wan ZongShun <mcuos.com@gmail.com>,
        linux-clk <linux-clk@vger.kernel.org>,
        Stephen Boyd <sboyd@codeaurora.org>,
        Michael Turquette <mturquette@baylibre.com>,
        Russell King <linux@armlinux.org.uk>,
        Alexandre Bailon <abailon@baylibre.com>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <20170720154616.3250481-1-arnd@arndb.de>
 <20170720155132.3250812-1-arnd@arndb.de>
 <b26930f6-3c57-7931-7f74-d0e07adb9cd7@ti.com>
 <CAK8P3a3C7xVmr6ZuJekhq8bdwqmoPeAkAqxJ+BUi9VrxkQpQZA@mail.gmail.com>
From: Sekhar Nori <nsekhar@ti.com>
Message-ID: <e5b9e449-62c8-948d-e6c0-fc5a575038b6@ti.com>
Date: Fri, 21 Jul 2017 15:14:46 +0530
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.2.1
MIME-Version: 1.0
In-Reply-To: <CAK8P3a3C7xVmr6ZuJekhq8bdwqmoPeAkAqxJ+BUi9VrxkQpQZA@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Friday 21 July 2017 01:47 PM, Arnd Bergmann wrote:
> On Fri, Jul 21, 2017 at 10:05 AM, Sekhar Nori <nsekhar@ti.com> wrote:
> 
>>> diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c
>>> index f5dce9b4e617..89586779526c 100644
>>> --- a/arch/arm/mach-davinci/clock.c
>>> +++ b/arch/arm/mach-davinci/clock.c
>>> @@ -218,6 +218,12 @@ int clk_set_parent(struct clk *clk, struct clk *parent)
>>>  }
>>>  EXPORT_SYMBOL(clk_set_parent);
>>>
>>> +struct clk *clk_get_parent(struct clk *clk)
>>> +{
>>> +     return clk->parent;
>>> +}
>>> +EXPORT_SYMBOL(clk_get_parent);
>>
>> For mach-davinci change:
>>
>> Acked-by: Sekhar Nori <nsekhar@ti.com>
> 
> Thanks!
> 
>>> diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
>>> index 39ef3b613912..c1c91fc6e178 100644
>>> --- a/arch/arm/mach-ep93xx/clock.c
>>> +++ b/arch/arm/mach-ep93xx/clock.c
>>> @@ -323,6 +323,27 @@ unsigned long clk_get_rate(struct clk *clk)
>>>  }
>>>  EXPORT_SYMBOL(clk_get_rate);
>>>
>>> +long clk_round_rate(struct clk *clk, unsigned long rate)
>>> +{
>>> +     WARN_ON(clk);
>>> +     return 0;
>>> +}
>>> +EXPORT_SYMBOL(clk_round_rate);
>>
>> Its probably better to WARN_ON_ONCE(). Also, since NULL clk is valid, it
>> should be probably be WARN_ON_ONCE(1).
> 
> I thought about trying to make it as correct as possible, but then went for
> the opposite approach and instead just made the functions as small as
> possible to avoid bloat while having the warning in there along with an
> obviously wrong implementation. Apparently the davinci version unlike
> the others ended up being a correct one after all (let me know if you
> want to have a NULL pointer check there).

Yeah, that would be better. Thanks!

Regards,
Sekhar