Messages in this thread | | | Date | Tue, 14 Jun 2016 16:39:48 +0200 | From | Alexandre Belloni <> | Subject | Re: [PATCH] rtc: ds1307: Fix relying on reset value for weekday |
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On 07/06/2016 at 14:59:05 +0530, Keerthy wrote : > Hi Alexandre, > > On Wednesday 01 June 2016 06:06 PM, Keerthy wrote: > > > > > > On Wednesday 01 June 2016 05:48 PM, Alexandre Belloni wrote: > > > Hi, > > > > > > On 01/06/2016 at 16:19:07 +0530, Keerthy wrote : > > > > The reset value of weekday is 0x1. This is wrong since > > > > the reset values of the day/month/year make up to Jan 1 2001. > > > > When computed weekday comes out to be Monday. On a scale > > > > of 1-7(Sunday - Saturday) it should be 0x2. So we should not > > > > be relying on the reset value. > > > > > > > > > > Hum, what are the chances that the reset value is actually the correct > > > date/time? > > > Won't that be corrected after the first call to set_time? Until then, > > > the date is not correct so, do we care anyway? > > > > Yes if an alarm is programmed without set_time. > > > > ex: rtcwake -d /dev/rtc0 -s 5 > > > > Even the basic rtctest under tools/testing/selftests/timers/rtctest.c fails > > as the wday is wrong and no alarm fires. > > > > Instead of relying on some one to call set_time before programming alarm > > its better to fix the wday to reflect the current day right? > > > > > > > > > > Maybe I'm missing something here. > > Let me know if you feel this is a valid fix. >
Well, this is probably a valid fix and I'll take it as is if I don't find the time to make something more generic.
-- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com
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