5V voltage incorrect on lm93

Hi,
I have been hunting down an issue related to the IN10 input of the
LM93. I have observed that there is a rather large error between the
actual voltage and the voltage level displayed by sensors(1) (~ .12V).

Please find attached a small patch that fixes this problem. The data
sheet is very ambiguous and I and another engineer made the same mistake calculating the voltage per DAC step the first time we read the spec sheet.

The confusion stems from an entry in the "maximum voltage" column that is higher than the value in the "absolute maximum range" column. For 5V only, the value in the "register reading at maximum voltage" is for the voltage in the "absolute maximum range", NOT the "maximum voltage". Whew!

I have tested this patch and it fixes the problem I just outlined. This patch is against lm_sensors 2.9.0.

David
-------------- next part --------------

@@ -689,7 +689,7 @@
 };
 static const unsigned long lm93_vin_val_max[16] = {
 	1236, 1236, 1236, 1600, 2000, 2000, 1600, 1600,
-	4400, 6667, 3333, 2625, 1312, 1312, 1236, 3600,
+	4400, 6500, 3333, 2625, 1312, 1312, 1236, 3600,
 };
 /*
 static const unsigned long lm93_vin_val_nom[16] = {

Hi David:

Sorry it took me so long to get to this, I've been swamped...

Right. I seem to remember wondering: "why would just that one channel have a non-linear scale?" I should have asked you to test that one specifically back when I first wrote the driver. You might also be able to get clarification directly from NatSemi.

Thanks, I've committed it to CVS.

Regards,

Mark M. Hoffman
[email protected]