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Date:   Wed, 21 Aug 2019 13:24:13 +0200
From:   Alexandre Belloni <alexandre.belloni@bootlin.com>
To:     Mark Brown <broonie@kernel.org>
Cc:     Li Yang <leoyang.li@nxp.com>, nandor.han@vaisala.com,
        Biwen Li <biwen.li@nxp.com>, a.zummo@towertech.it,
        linux-rtc@vger.kernel.org, lkml <linux-kernel@vger.kernel.org>
Subject: Re: [v2] rtc: pcf85363/pcf85263: fix error that failed to run
 hwclock -w
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On 21/08/2019 12:21:42+0100, Mark Brown wrote:
> On Tue, Aug 20, 2019 at 01:33:14PM -0500, Li Yang wrote:
> 
> > Some of the RTC hardware has the capability of address wrapping which
> > means if you access a continuous address range across a certain
> > boundary(could be the boundary of a regmap region) the hardware
> > actually wrap the access to a lower address.  But the address
> > violation check of regmap rejects such access.  According to
> > Alexcandre, the address wrapping is essential to the functionality of
> 
> It's *essential*?  Will innovation never cease?
> 

To be clear, for some RTCs, its is the only way to accurately set the
time.


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