linux-kernel - Re: [PATCH] regulator: Lookup unresolved parent supplies before regulators cleanup

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Message-ID: <56EFECC7.9030709@osg.samsung.com>
Date:	Mon, 21 Mar 2016 09:44:55 -0300
From:	Javier Martinez Canillas <javier@....samsung.com>
To:	Mark Brown <broonie@...nel.org>
Cc:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	Liam Girdwood <lgirdwood@...il.com>,
	Bjorn Andersson <bjorn.andersson@...aro.org>
Subject: Re: [PATCH] regulator: Lookup unresolved parent supplies before
 regulators cleanup

Hello Mark,

On 03/21/2016 09:37 AM, Mark Brown wrote:
> On Mon, Mar 21, 2016 at 09:13:55AM -0300, Javier Martinez Canillas wrote:
>> On 03/21/2016 08:11 AM, Mark Brown wrote:
>>> On Sun, Mar 20, 2016 at 11:39:46PM -0300, Javier Martinez Canillas wrote:
> 
>>>> This patch makes the unresolved parent supplies to be looked up before the
>>>> regulators late cleanup, so those with a child marked as always on will be
>>>> enabled regardless if a driver attempted to get the child regulator or not.
> 
>>> This doesn't make much sense to me as a fix - it feels like we're doing
>>> a fragile hack.  Surely it's better to do this as we register the
>>> devices, that way we're also protected against any similar issues with
> 
>> Sorry, not sure if I understood correctly. You mean to do it when the
>> drivers register the regulators, so at regulator_register() ?
> 
>> That's basically what was done before Bjorn's patch but that doesn't
>> handle the case of out of order registration when having circular
>> dependencies between regulators.
> 
> We used to look for the parent at registration time, we didn't look for
> the children.  What you're trying to do here is look for the children;
> we can do that at registration time.
>

Oh, now I understand what you meant. I thought you said to lookup the
parents at registration time, not the childrens. Great, I'll take a
look and give a try to your suggestion.

Thanks a lot for your help.

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