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

[Philip Rakity]

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>
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