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    SubjectRe: [PATCH] rtc: Add support for century bits to m41t62 (rv4162) RTC devices
    On 03/10/2019 14:21:50+0200, Lukasz Majewski wrote:
    > >
    > > See the datasheet:
    > >
    > > "During any year which is a multiple of 4, the RV-4162 RTC will
    > > automatically insert leap day, February 29. Therefore, the
    > > application software must correct for this during the exception years
    > > (2100, 2200, etc.) as noted above."
    >
    > I'm wondering what the phrase "application software" means here?
    >
    > If it is the userland SW, then we shall at least be able to set 2099 in
    > this device and then count on software correction.
    >
    > If the "application software" is the kernel driver - the date
    > correction shall be done there (maybe some lookup table?).
    >
    > Personally, I do prefer the first option - this means that with this
    > patch we can set the time to e.g. 2234 year and then rely on userland
    > software (or libc) to do the correction.
    >

    It is not possible to ensure this correction is properly done in
    software, there is no point in letting the user set those bits.


    --
    Alexandre Belloni, Bootlin
    Embedded Linux and Kernel engineering
    https://bootlin.com

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