Changeset 2496

Timestamp:

04/30/04 19:37:09 (9 years ago)

Author:

khali

Message:

Simplify temperature conversions.

Files:

• lm-sensors/trunk/kernel/chips/via686a.c (modified) (2 diffs)

lm-sensors/trunk/kernel/chips/via686a.c

@@ -270 +270 @@
 };
 
-/* Converting temps to (8-bit) hyst and over registers */
-// No interpolation here.  Just check the limits and go.
-// The +5 effectively rounds off properly and the +50 is because 
-// the temps start at -50
+/* Converting temps to (8-bit) hyst and over registers
+   No interpolation here.
+   The +50 is because the temps start at -50 */
 static inline u8 TEMP_TO_REG(long val)
 {
-        return (u8)
-            SENSORS_LIMIT(viaLUT[((val <= -500) ? 0 : (val >= 1100) ? 160 : 
-                                  ((val + 5) / 10 + 50))], 0, 255);
+        return viaLUT[val <= -500 ? 0 : val >= 1100 ? 160 : 
+                      (val < 0 ? val - 5 : val + 5) / 10 + 50];
 }
 
 /* for 8-bit temperature hyst and over registers */
-// The temp values are already *10, so we don't need to do that.
-// But we _will_ round these off to the nearest degree with (...*10+5)/10
-#define TEMP_FROM_REG(val) ((tempLUT[(val)]*10+5)/10)
+#define TEMP_FROM_REG(val) (tempLUT[(val)])
 
 /* for 10-bit temperature readings */
@@ -296 +292 @@
         u16 twoBits = val & 3;
 
-        // handle the extremes first (they won't interpolate well! ;-)
-        if (val == 0)
-                return (long) tempLUT[0];
-        if (val == 1023)
-                return (long) tempLUT[255];
-
-        if (twoBits == 0)
+        /* no interpolation for these */
+        if (twoBits == 0 || eightBits == 255)
                 return (long) tempLUT[eightBits];
-        else {
-                // do some interpolation by multipying the lower and upper
-                // bounds by 25, 50 or 75, then /100.
-                temp = ((25 * (4 - twoBits)) * tempLUT[eightBits]
-                        + (25 * twoBits) * tempLUT[eightBits + 1]);
-                // increase the magnitude by 50 to achieve rounding.
-                if (temp > 0)
-                        temp += 50;
-                else
-                        temp -= 50;
-                return (temp / 100);
-        }
+
+        /* do some linear interpolation */
+        temp = (4 - twoBits) * tempLUT[eightBits]
+             + twoBits * tempLUT[eightBits + 1];
+        /* achieve rounding */
+        return (temp < 0 ? temp - 2 : temp + 2) / 4;
 }