Re: [PATCH v2] mmc: sdhci: apply voltage range check only fornon-fixed regulators

From: Kevin Liu
Date: Wed Nov 14 2012 - 07:05:15 EST


2012/11/14 Philip Rakity <prakity@xxxxxxxxxx>:
>
> On Nov 14, 2012, at 8:57 AM, Kevin Liu <keyuan.liu@xxxxxxxxx> wrote:
>
>> 2012/11/14 Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>:
>>> On Wed, Nov 14, 2012 at 04:36:28PM +0800, Kevin Liu wrote:
>>>> 2012/11/14 Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>:
>>>
>>>>> Should this be regulator_set_voltage_tol()? Otherwise it'd be good to
>>>>> explain where the numbers come from.
>>>
>>>> In SD physical layer spec 3.01 chapter 6.6.1, the threshold level for
>>>> voltage range is defined as below:
>>>> Vdd(min) = 2.7V while Vdd(max) = 3.6V.
>>>> The card should work within the voltage range.
>>>
>>>> If you are afraid the voltage value is too aggressive, maybe we can
>>>> use regulator_set_voltage_tol() to set a smaller range.
>>>> But which range should be reasonable?
>>>
>>> The above makes total sense - thanks! I just wasn't aware that the
>>> range was specified in this fashion in the spec. Might be worth a
>>> comment in the code if you need to respin.
>>
>> Sure, I will update the patch. Thanks!
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>
>
> re-read spec. Please apply Kevin;s patch.
>
> Reviewed-by: Philip Rakity <prakity@xxxxxxxxxx>

Philip, thanks!
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