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Subject: Re: [PATCH 0/2] Enable GPIO and I2C configs for TI's J721e platform
To:     Faiz Abbas <faiz_abbas@ti.com>, <linux-kernel@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>
CC:     <will@kernel.org>, <catalin.marinas@arm.com>, <nm@ti.com>
References: <20201002164535.9920-1-faiz_abbas@ti.com>
 <68cadd9b-63b1-caaf-080c-e2f346f4a908@ti.com>
 <ce66e552-a816-9e67-5e94-d9a20bbc2bc7@ti.com>
From:   Tero Kristo <t-kristo@ti.com>
Message-ID: <f8877ca8-fe32-29e5-cb0c-2ce0af3eb73a@ti.com>
Date:   Tue, 6 Oct 2020 16:10:48 +0300
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On 06/10/2020 16:03, Faiz Abbas wrote:
> Hi Tero,
> 
> On 06/10/20 5:21 pm, Tero Kristo wrote:
>> On 02/10/2020 19:45, Faiz Abbas wrote:
>>> The following patches enable configs in the arm64 defconfig to support
>>> GPIO and I2C support on TI's J721e platform.
>>>
>>> Faiz Abbas (2):
>>>     arm64: defconfig: Enable OMAP I2C driver
>>>     arm64: defconfig: Enable DAVINCI_GPIO driver
>>>
>>>    arch/arm64/configs/defconfig | 2 ++
>>>    1 file changed, 2 insertions(+)
>>>
>>
>> Why are you enabling these?
>>
>> Are they required for booting the board?
>>
>> If not, they shall not be enabled, as it just clutters the arm64 defconfig unnecessarily.
>>
> 
> They are required because the SD card regulators need gpio over i2c expander and also
> soc gpio support to come up in UHS modes.

Is that needed for boot support? If it is only needed with UHS cards, 
that does not seem important enough for me. We can already boot the 
board via other means.

> 
> But in general isn't any feature we add supposed to be enabled in the arm64 defconfig?

That is debatable, as it just increases the kernel size / build time for 
everybody. Personally I would merge only things that are absolutely 
necessary, for everything else we can just do local config modifications.

-Tero
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