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

[Kevin Liu]

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!
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/