Hi, On 07/10/2015 at 01:19:09 +0200, Marek Vasut wrote : > >>/* The calculated value from the ADC is in Kelvin, we > >>* want Celsius for hwmon so the offset is > >>- * -272.15 * scale > >>+ * -273.15 * scale > >>*/ > >>- *val = -1075; > >>- *val2 = 691699; > >>+ *val = -1079; > >>+ *val2 = 644268; > >> > > > >i think it would be nice to break down the calculation of these magic values in > >a second patch. > > Indeed, I agree. I hope Alexandre can send another patch for that soon :-) > On my side, I'm not sure this is worth more than a comment. If necessary, I can write that the datasheet specifies that the scale is 4/1.012 here also. Else you end up with something like that (naive implementation): #define SCALE (4 * 1000 / 1012) val = -273150000 * SCALE / 1000000; val2 = 273150000 * SCALE + 1000000 * val; I don't feel this is any clearer because we can't use floating points in the kernel anyway. -- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
