Message-ID: <b58f5e31-f13f-6d90-774c-2017ee3de121@kontron.de>
Date:   Wed, 1 Feb 2023 17:26:08 +0100
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Subject: Re: [PATCH 0/7] Enable backup switch mode on RTCs via devicetree
Content-Language: en-US
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>
From:   Frieder Schrempf <frieder.schrempf@kontron.de>
In-Reply-To: <Y9qQHpySbrFcBB0P@mail.local>
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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.