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-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
