linux-kernel - [PATCH] RTC/PCF85063: fix reading/setting time/date

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Date:	Mon,  7 Dec 2015 14:49:31 +0100
From:	Juergen Borleis <jbe@...gutronix.de>
To:	rtc-linux@...glegroups.com
Cc:	Alessandro Zummo <a.zummo@...ertech.it>,
	Alexandre Belloni <alexandre.belloni@...e-electrons.com>,
	linux-kernel@...r.kernel.org, kernel@...gutronix.de
Subject: [PATCH] RTC/PCF85063: fix reading/setting time/date

The PCF85063 RTC needs special treatment while setting or reading the
time/date:

 - while reading the 7 time/date registers they are blocked from updating by
   the one second pulse internally. So reading all time/date registers should
   happen in one turn to ensure reading is an atomic operation

 - to let setting the time/date be an atomic operation as well, the clock
   dividers must be kept in reset state to avoid a one second pulse during
   writing the 7 time/date registers

Patch 1 and 2 change reading the time/date. I have kept them separately for
easier review. Squasching both into one patch render it more or less
unreadable.
Patch 3 changes setting the time/date.

Comments are welcome
Juergen

Please keep me on CC as I'm not subscribed to the list.

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