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From: Tomasz Figa <tomasz.figa@gmail.com>
To: Mark Brown <broonie@kernel.org>
Cc: Javier Martinez Canillas <javier.martinez@collabora.co.uk>,
	Doug Anderson <dianders@chromium.org>,
	Olof Johansson <olof@lixom.net>,
	Yuvaraj Kumar C D <yuvaraj.cd@gmail.com>,
	linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] regulator: max77802: set opmode to normal if off is read from hw
Date: Wed, 27 Aug 2014 20:39:39 +0200	[thread overview]
Message-ID: <53FE25EB.7060702@gmail.com> (raw)
In-Reply-To: <20140827183733.GN17528@sirena.org.uk>

On 27.08.2014 20:37, Mark Brown wrote:
> On Wed, Aug 27, 2014 at 08:32:38PM +0200, Tomasz Figa wrote:
>> On 26.08.2014 13:37, Javier Martinez Canillas wrote:
> 
>>> +		/*
>>> +		 * If the regulator is disabled and the system warm rebooted,
>>> +		 * the hardware reports OFF as the regulator operating mode.
>>> +		 * Default to operating mode NORMAL in that case.
>>> +		 */
>>> +		if (val == MAX77802_OPMODE_OFF)
>>> +			max77802->opmode[id] = MAX77802_OPMODE_NORMAL;
>>> +		else
>>> +			max77802->opmode[id] = val;
> 
>> I might be missing something, but I believe I see a flaw here. If after
>> a cold boot opmode is something else than OFF or NORMAL, the kernel
>> starts, turns the regulator off and does warm reboot, the setting is
>> lost and the regulator is switched to NORMAL mode.
> 
> 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).

  reply	other threads:[~2014-08-27 18:39 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-26 11:37 [PATCH 1/1] regulator: max77802: set opmode to normal if off is read from hw Javier Martinez Canillas
2014-08-26 15:44 ` Doug Anderson
2014-08-27  6:47 ` Yuvaraj Kumar
2014-08-27 17:51 ` Mark Brown
2014-08-27 18:32 ` Tomasz Figa
2014-08-27 18:37   ` Mark Brown
2014-08-27 18:39     ` Tomasz Figa [this message]
2014-08-27 18:47       ` Mark Brown
2014-08-27 18:52         ` Tomasz Figa
2014-08-27 19:15           ` Mark Brown
2014-08-27 19:21             ` Tomasz Figa
2014-08-27 19:44               ` Mark Brown
2014-08-27 19:58                 ` Tomasz Figa
2014-08-27 20:25                   ` Mark Brown
2014-08-27 20:41                     ` Tomasz Figa
2014-08-27 21:03                       ` Tomasz Figa
2014-08-27 22:44                         ` Javier Martinez Canillas
2014-08-28  8:28                           ` Mark Brown
2014-08-28  9:59                             ` Javier Martinez Canillas
2014-08-28 10:01                               ` Mark Brown
2014-08-27 21:03                       ` Mark Brown

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