Re: [PATCH v2 00/10] rtc: max77686: Extend driver and add max77802 support

From: Javier Martinez Canillas
Date: Mon Jan 25 2016 - 18:45:54 EST


Hello Alexandre,

On 01/25/2016 01:06 PM, Alexandre Belloni wrote:
Hi,

On 21/01/2016 at 17:23:23 -0300, Javier Martinez Canillas wrote :
On a recent disussion [0] with Krzysztof Kozlowski and Laxman Dewangan,
we came to the conclusion that the max77686 and max77802 RTC are almost
the same with only a few differences so there shouldn't be two separate
drivers and is better to extend max77686 driver and delete rtc-max77802.

By making the driver more generic, other RTC IP blocks from Maxim PMICs
could be supported as well like the max77620.

This is a v2 of a series that do this, that address issues pointed out
by Krzysztof Kozlowski. The v1 can be found at [1].

I've tested this patch-set on an Exynos5800 Peach Pi Chromebook that has
a max77802 PMIC and the RTC was working correctly but I don't have a
machine with max77686 so I will really appreaciate if someone can test
that no regressions were introduced.

On an IRC conversation, Alexandre suggested to use the field support in
the regmap API to avoid needing a translation table. I spent some time
to look at it and I'm not so sure if it fits that well in this case.

It's true that we could model each register as if it has a single field
and provide a different reg address but I'm not sure if that would make
things more clear or cause more confusion for future code archaeologists.


Yeah, Mark suggested that regmap_field may be what we were looking for
but I'm not convinced it really fits.


Ok.
In any case, I think this series are a move in the right direction since
removes code duplication and a complete driver and also allows others to
reuse the driver for another RTC chip. We can later simplify and use the
regmap field API or extend the regmap core if that could make things even
simpler but I propose to do it as a follow up.


I don't have any objection or other comment on that series. So
basically, I'm waiting for v3 and I'll apply it.



Great, I'll post a v3 tomorrow then. Thanks!

Best regards,
--
Javier Martinez Canillas
Open Source Group
Samsung Research America