Re: [rtc-linux] [PATCH 2/2] rtc: Add boot_timesource sysfsattribute

From: Alessandro Zummo
Date: Fri Sep 04 2009 - 12:25:43 EST

On Fri, 4 Sep 2009 12:26:08 -0400
Matthew Garrett <mjg@xxxxxxxxxx> wrote:

> CONFIG_RTC_HCTOSYS allows the kernel to read the system time from the RTC
> at boot and resume, avoiding the need for userspace to do so. Unfortunately
> userspace currently has no way to know whether this configuration option
> is enabled and thus cannot sensibly choose whether to run hwclock itself or
> not. Add a boot_timesource sysfs attribute which indicates whether a given
> RTC set the system clock.

This feature is meant to be in addition of the regular
hwclock call to read the system time.

Have you tested if there are drawbacks by not reading it? Like
TZ, DST and similar?


Best regards,

Alessandro Zummo,
Tower Technologies - Torino, Italy

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