#!/bin/sh
#
# /usr/local/sbin/freq
#   simple command line interface to cpufreq
#
# Michael Ossmann <mike@ossmann.com>
#   Original work
# Jean Delvare <khali@linux-fr.org>
#   ACPI support
#
# TODO: SMP support

if [ ! -r /proc/sys/cpu/0/speed ]
then
  echo "Missing cpufreq support."
  exit 1
fi

[ -n "$1" ] && case "$1" in
  "min" )
    # set frequency to minimum
    cat /proc/sys/cpu/0/speed-min > /proc/sys/cpu/0/speed
    echo "CPU 0 frequency set to $(cat /proc/sys/cpu/0/speed) MHz."
    exit 0
    ;;
  "max" )
    # set frequency to maximum
    cat /proc/sys/cpu/0/speed-max > /proc/sys/cpu/0/speed
    echo "CPU 0 frequency set to $(cat /proc/sys/cpu/0/speed) MHz."
    exit 0
    ;;
  "acpi" )
    # use ACPI to choose frequency
    if [ ! -r /proc/acpi/ac_adapter/*/state ]
    then
      echo "Missing ACPI support."
      exit 1
    fi
    if grep 'off-line' /proc/acpi/ac_adapter/*/state > /dev/null
    then
      cat /proc/sys/cpu/0/speed-min > /proc/sys/cpu/0/speed
    else
      cat /proc/sys/cpu/0/speed-max > /proc/sys/cpu/0/speed
    fi
    echo "CPU 0 frequency set to $(cat /proc/sys/cpu/0/speed) MHz."
    exit 0
    ;;
  * )
    echo "Usage: $0 [min|max|acpi]"
    echo "  min        set frequency to minimum"
    echo "  max        set frequency to maximum"
    echo "  acpi       use ACPI to choose frequency"
    echo "  default    display current frequency"
    exit 1
    ;;
esac

# display current frequency
echo "CPU 0 frequency is $(cat /proc/sys/cpu/0/speed) MHz."