linux-kernel - Re: [PATCH 4/4] regulator: arizona-ldo1: Do not control clocking from regulator

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Message-ID: <20140609184314.GB5099@sirena.org.uk>
Date:	Mon, 9 Jun 2014 19:43:14 +0100
From:	Mark Brown <broonie@...nel.org>
To:	Richard Fitzgerald <rf@...nsource.wolfsonmicro.com>
Cc:	sameo@...ux.intel.com, lee.jones@...aro.org,
	ckeepax@...nsource.wolfsonmicro.com, lgirdwood@...il.com,
	perex@...ex.cz, tiwai@...e.de, alsa-devel@...a-project.org,
	patches@...nsource.wolfsonmicro.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 4/4] regulator: arizona-ldo1: Do not control clocking
 from regulator

On Mon, Jun 09, 2014 at 04:04:35PM +0100, Richard Fitzgerald wrote:
> Using the driver for the internal regulator to also control
> the clock frequency of blocks inside the codec is an
> unexpected side-effect for a regulator, and also means that
> the core clocks won't be changed as expected if an external
> regulator is used to power the codec.

IIRC this was deliberately coded in this fashion on advice from the
hardware engineers - there was more going on with that register than
there might at first appear and some actual sync with the LDO.  I
believe there was some different process to follow (possibly just
setting this mode all the time) when using an external regulator, though
it's also possible the hardware guys were just unsure at the time.

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