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Subject: Re: [PATCH v8 1/6] ARM: imx6q: provide documentation for new
 fsl,pmic-stby-poweroff property
From:   Lucas Stach <l.stach@pengutronix.de>
To:     Robin Gong <yibin.gong@nxp.com>,
        Oleksij Rempel <o.rempel@pengutronix.de>,
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Date:   Mon, 06 Aug 2018 18:49:32 +0200
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Am Montag, den 06.08.2018, 02:34 +0000 schrieb Robin Gong:
> > > > Not all boards follow the reference design, that's a fact of
> > > > life.
> > > > 
> > > > Please look at the i.MX6Q reference manual. The sequence
> > > > implemented
> > > > in this patchset can be found as a valid way to power off the
> > > > system
> > > > in
> > > > "60.4.3 Power mode transitions" "Normal ON to OFF with external
> > > > PMIC", so there is hardly any way to argue that this is a board
> > > > specific quirk. This is one of the Freescale/NXP recommended
> > > > sequences to
> > 
> > turn off the system.
> > 
> > > Okay, but could you add one more comment for this solution? RTC
> > > alarm
> > > and ONOFF Button wakeup feature can't be support in this case.
> > 
> > Enough to add it in to changelog? or should it go to the binding
> > documentation?
> 
> The binding doc is better.

Sorry, I disagree.

A binding is a way to describe a specific hardware layout, it isn't the
right place to advice a hardware designer on the implications of a
specific hardware implementation. The NXP hardware design guide is a
more suitable place for this information.

We also don't mention in random bindings that the system won't be able
to brew a fresh cup of coffee.

Regards,
Lucas