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Message-ID: <847cc6c8-e097-aa3a-2cd7-a6929bec18e9@linaro.org>
Date:   Tue, 4 Apr 2023 12:06:14 +0200
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Subject: Re: [PATCH v5 2/2] dt-bindings: rtc: add max313xx RTCs
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To:     Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc:     Ibrahim Tilki <Ibrahim.Tilki@analog.com>, a.zummo@towertech.it,
        jdelvare@suse.com, linux@roeck-us.net, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, linux-rtc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org,
        devicetree@vger.kernel.org,
        Zeynep Arslanbenzer <Zeynep.Arslanbenzer@analog.com>
References: <20230403154342.3108-1-Ibrahim.Tilki@analog.com>
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 <dd6f0842-519f-1bc9-f7f5-459863dc3dcd@linaro.org>
 <202304040710049c9cc01a@mail.local>
 <996b49ab-5e2e-76bc-efb1-38c6384871f6@linaro.org>
 <2023040407444619bf5596@mail.local>
 <0fd972bd-c5e7-65cc-6992-09c4c3e88f95@linaro.org>
 <202304040956056c59af98@mail.local>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <202304040956056c59af98@mail.local>
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On 04/04/2023 11:56, Alexandre Belloni wrote:
> On 04/04/2023 10:14:33+0200, Krzysztof Kozlowski wrote:
>> On 04/04/2023 09:44, Alexandre Belloni wrote:
>>>>
>>>>> charging will always
>>>>> enable a diode, select a resistor and then have or not an extra diode.
>>>>> Figure2 of the MAX31329 datasheet is great.
>>>>
>>>> So the diode is in the max313xx? Then why enabling it is a property of
>>>> DT? Either this should be inferred from compatible or is even a policy,
>>>> not a DT property. Just because device has a register for something, is
>>>> not an argument that "something" should be in DT.
>>>
>>> Well, it depends on the battery that is installed on the board so it
>>> makes sense to have it in DT.
>>
>> OK, that would be a good reason, but I wonder why? Why choosing diode or
>> not depends on the battery? Wouldn't you always want to have the diode?
>>
> 
> It limits the maximum current used to charge the battery or supercap to
> not exceed what is allowed.

and I still wonder why someone would like to allow exceeding what is
allowed. IOW, what is the use case to disable the diode?

Best regards,
Krzysztof