Re: [PATCH 1/3] ARM: dts: omap5-board-common: enable rtc and charging of backup battery

From: H. Nikolaus Schaller
Date: Wed Jan 13 2016 - 13:00:49 EST



Am 13.01.2016 um 18:38 schrieb Nishanth Menon <nm@xxxxxx>:

> On 01/13/2016 11:12 AM, Grygorii Strashko wrote:
>> On 01/13/2016 06:48 PM, Tony Lindgren wrote:
>
> [...]
>
>>> Care to dig up some more information on that?
>>
>> i can't find this report, sry - as i remember there was difference
>> between some OMAP4 HS and GP SoCs.
>>
>> But links on commits for old 3.4 kernel below:
>> http://omapzoom.org/?p=kernel/omap.git;a=commitdiff;h=a7a516be9338eabc9a7682e7433fa34d86c1f208
>> http://omapzoom.org/?p=kernel/omap.git;a=commitdiff;h=262669aebf4af4044a25e8292f0e27986e18445a
>>
>>>
>>> I don't have anything against adding GPIO handling to the TWL driver
>>> so it can be optionally specified. But that's clearly a separate patch
>>> and should be done by somebody who knows more about the issue and has
>>> a test case needing the GPIO logic for this pin.
>>>
>>
>>
> if it helps in anyways
> http://lists.infradead.org/pipermail/linux-arm-kernel/2013-May/170707.html

>> Yes, the TRM has some mode bits marked as reserved, but that doesn't
>> mean they don't work. It just means the documentation is squirreled
>> away in the secure TRM addendum.

Ok, now I understand why the "reserved" MUX_MODE1 could still be correct
for OMAP5. And that I just have a "squirreled away" version of the TRM which
made me wonder what is going on.

>From this discussion I read that for X15 there is a different PMIC
(Palmas derived, but not a twl6037) so that it needs something different.

So my proposal would be to keep the MUX_MODE1 (because it works
on OMAP5+TWL6037) as proposed by Tony. Maybe after adding a comment
that MUX_MODE1 is a weakly documented feature.

And the X15 board can "patch" it after using the omap5-board-common.dtsi
to whatever it needs to fix it.

BR,
Nikolaus