pwmconfig: Use smaller steps for low PWM values. Inspired from a patch

from the openSuse sensors package. This is a good idea because the
PWM/speed relation isn't linear, and it is frequent that the speed
changes are concentrated in the low PWM range.


git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@4380 7894878c-1315-0410-8ee3-d5d059ff63e0

CHANGES

@@ -8,6 +8,7 @@ SVN HEAD
            Add dme1737 support
   Man page sensors.conf.5: Update the chip statement section
   Program isadump: Detect when address bit 7 is a busy flag
+  Program pwmconfig: Use smaller steps for low PWM values
   Program rrd: Support non-i2c devices (hwmon class)
                Add missing shell declarations
                Update URI

prog/pwm/pwmconfig

@@ -248,6 +248,10 @@ echo
 PLOTTER=gnuplot
 STEP=15
 PDELAY=2
+# Use a smaller step for low PWM values as this is typically where the
+# more important fan speed changes are happening.
+STEP2=2
+STEP2_BELOW=31
 
 function pwmdetail()
 {
@@ -315,7 +319,12 @@ function pwmdetail()
 			fi
 			break
 		fi
-		let pwm=$pwm-$STEP
+		if [ $pwm -lt $STEP2_BELOW ]
+		then
+			let pwm=$pwm-$STEP2
+		else
+			let pwm=$pwm-$STEP
+		fi
 	done
 	pwmdisable $P	
 	if [ "$PLOT" = "y" ]