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Date:   Tue, 8 Sep 2020 11:39:46 +0200
From:   Alexandre Belloni <alexandre.belloni@bootlin.com>
To:     Jonathan =?iso-8859-1?Q?Neusch=E4fer?= <j.neuschaefer@gmx.net>
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Subject: Re: [PATCH v2 07/10] rtc: Introduce RTC_TIMESTAMP_END_2255
Message-ID: <20200908093946.GQ230586@piout.net>
References: <20200905133230.1014581-1-j.neuschaefer@gmx.net>
 <20200905133230.1014581-8-j.neuschaefer@gmx.net>
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On 05/09/2020 15:32:27+0200, Jonathan Neusch?fer wrote:
> Some RTCs store the year as an 8-bit number relative to the year 2000.
> This results in a maximum timestamp of 2255-12-31 23:59:59.
> 
> Signed-off-by: Jonathan Neusch?fer <j.neuschaefer@gmx.net>
> ---
> 
> v2:
> - New patch
> ---
>  include/linux/rtc.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/include/linux/rtc.h b/include/linux/rtc.h
> index 22d1575e4991b..fcc086084a603 100644
> --- a/include/linux/rtc.h
> +++ b/include/linux/rtc.h
> @@ -154,6 +154,7 @@ struct rtc_device {
>  #define RTC_TIMESTAMP_END_2079		3471292799LL /* 2079-12-31 23:59:59 */
>  #define RTC_TIMESTAMP_END_2099		4102444799LL /* 2099-12-31 23:59:59 */
>  #define RTC_TIMESTAMP_END_2199		7258118399LL /* 2199-12-31 23:59:59 */
> +#define RTC_TIMESTAMP_END_2255		9025257599LL /* 2255-12-31 23:59:59 */

Honestly, I wouldn't bother adding that one unless you have examples of
other RTCs endng at the same date, I'm fine having the value and comment
directly in the probe function.

>  #define RTC_TIMESTAMP_END_9999		253402300799LL /* 9999-12-31 23:59:59 */
> 
>  extern struct rtc_device *devm_rtc_device_register(struct device *dev,
> --
> 2.28.0
> 

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