Re: [PATCH 1/1] regulator: max77802: set opmode to normal if off is read from hw
From: Tomasz Figa
Date: Wed Aug 27 2014 - 14:52:58 EST
On 27.08.2014 20:47, Mark Brown wrote:
> On Wed, Aug 27, 2014 at 08:39:39PM +0200, Tomasz Figa wrote:
>> On 27.08.2014 20:37, Mark Brown wrote:
>>> That's essentially the situation the patch is trying to fix - if we boot
>>> and the regulator is off there's no way to figure out what the operating
>>> mode would have been so we have to pick something. If you've got an
>>> idea for something better to do...
>> Probably the only way to correctly handle this is to specify the right
>> operating mode in DT (after defining a binding for it).
> I'm not convinced that's worth it - chances are that if anything changed
> the mode it was a previously running Linux which will most likely be
> doing the same things when it starts running anyway.
The previously running Linux would have changed the opmode accidentally,
due to hardware design of PMIC chip, which doesn't allow powering off a
regulator in other way than setting opmode to OFF.
If you provide the "active" opmode to that Linux, after a warm reboot it
will be able to power on such regulator to correct opmode, without
defaulting it incorrectly to NORMAL.
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