add separate init script and tweak ondemand params

debian/raspi-config.init

@@ -0,0 +1,37 @@
+#!/bin/sh
+### BEGIN INIT INFO
+# Provides:          raspi-config
+# Required-Start: udev mountkernfs $remote_fs
+# Required-Stop:
+# Default-Start: S
+# Default-Stop:
+# Short-Description: Switch to ondemand cpu governor (unless shift key is pressed)
+# Description:
+### END INIT INFO
+
+. /lib/lsb/init-functions
+
+case "$1" in
+  start)
+    log_daemon_msg "Checking if shift key is held down"
+    timeout 1 thd --dump /dev/input/event* | grep -q "LEFTSHIFT\|RIGHTSHIFT"
+    if [ $? -eq 0 ]; then
+      printf " Yes. Not enabling ondemand scaling governor"
+      log_end_msg 0
+    else
+      printf " No. Switching to ondemand scaling governor"
+      SYS_CPUFREQ_GOVERNOR=/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
+      if [ -e $SYS_CPUFREQ_GOVERNOR ]; then
+        echo "ondemand" > $SYS_CPUFREQ_GOVERNOR
+        echo 50 > /sys/devices/system/cpu/cpufreq/ondemand/up_threshold
+        echo 100000 > /sys/devices/system/cpu/cpufreq/ondemand/sampling_rate
+        echo 50 > /sys/devices/system/cpu/cpufreq/ondemand/sampling_down_factor
+      fi
+      log_end_msg 0
+    fi
+    ;;
+  *)
+    echo "Usage: $0 start" >&2
+    exit 3
+    ;;
+esac