From mboxrd@z Thu Jan 1 00:00:00 1970 From: pavel@denx.de (Pavel Machek) Date: Tue, 16 Jul 2019 23:03:50 +0200 Subject: [cip-dev] [PATCH 4.4.y-cip 03/10] rtc: pcf85363: set time accurately In-Reply-To: <1563264921-42973-4-git-send-email-biju.das@bp.renesas.com> References: <1563264921-42973-1-git-send-email-biju.das@bp.renesas.com> <1563264921-42973-4-git-send-email-biju.das@bp.renesas.com> Message-ID: <20190716210350.GB14181@amd> To: cip-dev@lists.cip-project.org List-Id: cip-dev.lists.cip-project.org On Tue 2019-07-16 09:15:14, Biju Das wrote: > commit 188306ac9536ec47674ffa9dd330f69927679aeb upstream. > > As per 8.2.6 Setting and reading the time in RTC mode, first stop the clok, > then reset it before setting the date and time registers. Finally, start > the clock. > > This uses register address wrap around from 0x2f to 0x00 for > efficiency. How does wrap around work? AFAICT it is supposed to have ram at 0x40. Does it really provide increased efficiency (given regmap layer in between) and will such trick cause problems in future? If regmap is not aware of register mirrors it might get confused and provide stale values, for example... Best regards, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 181 bytes Desc: Digital signature URL: