Message-ID: <da83fdd0-9eae-09ce-ff6f-47cc012f9628@kontron.de>
Date:   Mon, 6 Mar 2023 14:27:06 +0100
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Subject: Re: [PATCH 0/7] Enable backup switch mode on RTCs via devicetree
Content-Language: en-US
From:   Frieder Schrempf <frieder.schrempf@kontron.de>
To:     Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Frieder Schrempf <frieder@fris.de>
Cc:     devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, linux-rtc@vger.kernel.org,
        Alessandro Zummo <a.zummo@towertech.it>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Shawn Guo <shawnguo@kernel.org>
References: <20230201143431.863784-1-frieder@fris.de>
 <Y9qQHpySbrFcBB0P@mail.local>
 <b58f5e31-f13f-6d90-774c-2017ee3de121@kontron.de>
 <7268b05b-bbb1-ec4d-6a05-f5ccbdfeed90@kontron.de>
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On 13.02.23 10:18, Frieder Schrempf wrote:
> Hi Alexandre,
> 
> On 01.02.23 17:26, Frieder Schrempf wrote:
>> On 01.02.23 17:15, Alexandre Belloni wrote:
>>> Hello,
>>>
>>> You can't do that, this breaks an important use case and it is the
>>> reason why I didn't use device tree in the beginning. What is wrong with
>>> setting BSM from userspace? You will anyway have to set the time and
>>> date from userspace for it to be saved.
>>
>> Ok, I was already afraid there is something I missed. Can you give a
>> short explanation of what use case this would break?
>>
>> There is nothing wrong with setting BSM from userspace. It's just the
>> fact that users expect BSM to be enabled in any case as there is a
>> battery on the board. It is much more effort to ensure that production,
>> user, etc. are aware of an extra step required than to let the kernel
>> deal with it behind the scenes.
> 
> Would you mind elaborating on your argument that this would break stuff?
> I currently don't see how an additional optional devicetree property
> would break anything.

Ping!?