battery_cutoff/battery_cutoff.sh

#!/bin/sh

# Copyright 2015 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# This script controls battery power level and performs required battery
# cutoff protection by sending commands to EC with ectool.

SCRIPT_DIR="$(dirname "$(readlink -f "$0")")"

DISPLAY_MESSAGE="${SCRIPT_DIR}/display_wipe_message.sh"

# After calling display_wipe_message.sh to draw image with frecon, we must
# redirect text output to tty1 to display information on the screen.
TTY=/dev/tty1

usage_help() {
  echo "Usage: $0
    [--method shutdown|reboot|battery_cutoff]
    [--check-ac connect_ac|remove_ac]
    [--min-battery-percent <minimum battery percentage>]
    [--max-battery-percent <maximum battery percentage>]
    [--min-battery-voltage <minimum battery voltage>]
    [--max-battery-voltage <maximum battery voltage>]"
}

reset_activate_date() {
  /usr/sbin/activate_date --clean
}

has_battery() {
  ( type ectool && ectool battery ) >/dev/null 2>&1
}

get_battery_percentage() {
  local full="" current=""
  full="$(ectool battery 2>/dev/null |
    awk '/Last full charge/ {print int($4)}')"
  current="$(ectool battery 2>/dev/null |
    awk '/Remaining capacity/ {print int($3)}')"
  echo $((current * 100 / full))
}

get_battery_voltage() {
  ectool battery 2>/dev/null | awk '/Present voltage/ {print int($3)}'
}

is_ac_present() {
  ectool battery | grep -q AC_PRESENT
}

require_ac() {
  if ! is_ac_present; then
    "${DISPLAY_MESSAGE}" "connect_ac"
    while ! is_ac_present; do
      sleep 0.5
    done
  fi
}

require_remove_ac() {
  if is_ac_present; then
    "${DISPLAY_MESSAGE}" "remove_ac"
    while is_ac_present; do
      sleep 0.5
    done
  fi
}

check_battery_value() {
  local min_battery_value="$1" max_battery_value="$2"
  local get_value_cmd="$3"
  local battery_value=""
  local prev_battery_value=""

  battery_value="$(${get_value_cmd})"

  if [ -n "$min_battery_value" ] &&
     [ "$battery_value" -lt "$min_battery_value" ]; then
    require_ac
    ${DISPLAY_MESSAGE} "charging"

    # Wait for battery to charge to min_battery_value
    prev_battery_value="-1"
    # Print a new line before and after showing battery info.
    echo ""
    while [ "$battery_value" -lt "$min_battery_value" ]; do
      # Only print battery info when it changes.
      if [ "$battery_value" -ne "$prev_battery_value" ]; then
        # Keep printing battery information in the same line.
        printf '\rcurrent: %s, target: %s' \
            "$battery_value" "$min_battery_value" >"${TTY}"
        prev_battery_value="$battery_value"
      fi
      sleep 1
      battery_value="$(${get_value_cmd})"
    done
    echo ""
  fi

  if [ -n "$max_battery_value" ] &&
     [ "$battery_value" -gt "$max_battery_value" ]; then
    require_remove_ac
    ${DISPLAY_MESSAGE} "discharging"

    # Wait for battery to discharge to max_battery_value
    prev_battery_value="-1"
    # Print a new line before and after showing battery info.
    echo ""
    while [ "$battery_value" -gt "$max_battery_value" ]; do
      # Only print battery info when it changes.
      if [ "$battery_value" -ne "$prev_battery_value" ]; then
        # Keep printing battery information in the same line.
        printf '\rcurrent: %s, target: %s' \
            "$battery_value" "$max_battery_value" >"${TTY}"
        prev_battery_value="$battery_value"
      fi
      sleep 1
      battery_value="$(${get_value_cmd})"
    done
    echo ""
  fi
}

check_ac_state() {
  local cutoff_ac_state="$1"
  if [ "$cutoff_ac_state" = "connect_ac" ]; then
    require_ac
  elif [ "$cutoff_ac_state" = "remove_ac" ]; then
    require_remove_ac
  fi
}

main() {
  local cutoff_method=""
  local cutoff_ac_state=""
  local min_battery_percent="" max_battery_percent=""
  local min_battery_voltage="" max_battery_voltage=""

  local key
  while [ $# -ge 1 ]
  do
    key="$1"
    case "$key" in
      "--method" )
        cutoff_method="$2"
        shift 2
        ;;
      "--check-ac" )
        cutoff_ac_state="$2"
        shift 2
        ;;
      "--min-battery-percent" )
        min_battery_percent="$2"
        shift 2
        ;;
      "--max-battery-percent" )
        max_battery_percent="$2"
        shift 2
        ;;
      "--min-battery-voltage" )
        min_battery_voltage="$2"
        shift 2
        ;;
      "--max-battery-voltage" )
        max_battery_voltage="$2"
        shift 2
        ;;
      * )
        usage_help
        exit 1
        ;;
    esac
  done

  reset_activate_date

  if has_battery; then
    # Needed by 'ectool battery'.
    mkdir -p /var/lib/power_manager
    modprobe i2c_dev
    if [ -n "$min_battery_percent" ] || [ -n "$max_battery_percent" ]; then
      check_battery_value "$min_battery_percent" "$max_battery_percent" \
        "get_battery_percentage"
    fi
    if [ -n "$min_battery_voltage" ] || [ -n "$max_battery_voltage" ]; then
      check_battery_value "$min_battery_voltage" "$max_battery_voltage" \
        "get_battery_voltage"
    fi
  fi

  # Ask operator to plug or unplug AC before doing cut off.
  check_ac_state "$cutoff_ac_state"

  $DISPLAY_MESSAGE "cutting_off"

  # TODO (shunhsingou): In bug
  # https://bugs.chromium.org/p/chromium/issues/detail?id=589677, small amount
  # of devices fail to do cut off in factory. This may be caused by unstable
  # ectool, or shutdown fail in the tmpfs. Here we add more retries for
  # solving this problem. Remove the retry when finding the root cause.
  for i in $(seq 5)
  do
    case "$cutoff_method" in
      "shutdown" )
        shutdown -h now
      ;;
      "reboot" )
        reboot
      ;;
      "battery_cutoff" )
        crossystem battery_cutoff_request=1 && sleep 3 && reboot
      ;;
      * )
        # By default we shutdown the device without doing anything.
        shutdown -h now
    esac
    sleep 15
  done

  $DISPLAY_MESSAGE "cutoff_failed"
  sleep 1d
  exit 1
}

main "$@"