=====Laptop Hacks=====

Ho boy, this got difficult really quickly - in 2011 I had everything working on my laptop (Dell XPS-15 L502X) with the LXDE spin of fedora plus fluxbox. After a quick spurt of travel using all the laptoppy things like conserving battery life, suspend/resume and lid up and down I left it alone, using it like a desktop on AC power but updating through various fedora's. Quite unbeknownst to me, ''systemd'' came in and the laptoppy stuff got broken - I had to re-discover how to do everything again. Now I know and understand some of it and hopefully recording it here will help me next time.

Maybe it'll help you too - but you will almost certainly need to some make tweaks for your particular setup.

Why go through all this? Why not just use a full DE like KDE or gnome to take care of it? With KDE the best I could get was about 4 hours of battery life. By doing the hard work and understanding what's going on I can get up to 6.5 hours! Not bad.

====Who's doing the work?====

Several players:

  * acpid: for suspend
  * DBus: for power connect/disconnect
  * acpi: to get battery status
  * systemctl: but, of course!
  * ???: DBus? lid opening & closing - just seems to work

====Suspend====

Install ''acpid'' and ''acpi'' and then:

  systemctl enable acpid
  systemctl start acpid

Put this into ''/etc/acpi/events/sleepconf'':

  event=button/sleep
  action=systemctl suspend

====Tweaking touchpad====

Seems the synaptics driver is deprecated in favour of libinput - put tweaks in /etc/X11/xorg.conf.d/30-touchpad.conf:

  Section "InputClass"
      Identifier "touchpad"
      Driver "libinput"
      MatchIsTouchpad "on"
      Option "Tapping" "on"
      Option "TappingButtonMap" "lmr"
      Option "ScrollMethod" "edge"
  EndSection

====Power Disconnect/Connect events====

These events come through DBus, so I run this in my ''.xsession''.

  # if there's a battery then listen on dbus for a/c connect/disconnect:
  upower -e |grep -q battery && {
      power-monitor &
      xfce4-power-manager &
  }

Where, ''power-monitor'' is this bit of python which keeps an eye on remaining battery life (and hibernate as it gets low) but also runs the ''low-power'' script when the power/battery status changes:

  #!/bin/env python
  
  # needs to run as normal user under X (so that battery-alarm can popup)
  # requires dbus-python
  
  import gobject, os, sys
  gobject.threads_init()
  
  from dbus import glib
  glib.init_threads()
  import dbus
  bus = dbus.SystemBus()
  
  sys.dont_write_bytecode = True
  
  def backtick(command):
      """
      Equivalent of Bourne shell's backtick
      See http://www.python.org/doc/2.5.1/lib/node534.html
      """
      from subprocess import Popen, PIPE
      #print "backtick: command='%s'\n" % command
      value = Popen(["sh", "-c", command], stdout=PIPE).communicate()[0].rstrip()
      #print "returning '%s'\n" % value
      return(value)
  
  # power connection events
  def ac(*args, **kwargs):
      print("[" + backtick("date '+%Y%m%d:%H%M%S'") + "] power-monitor: ac: args = ")
      print args
      try:
          if args[1]['Online'] == 0:
              print("power-monitor: ac: unplugged - calling low-power true")
              os.system("low-power true")
          else:
              print("power-monitor: ac: plugged in - calling low-power false")
              os.system("low-power false")
      except:
          pass
  
  # warn user or suspend
  def check_battery(*args, **kwargs):
      battery_status = backtick("acpi -b")
      print("[" + backtick("date '+%Y%m%d:%H%M%S'") + "] power-monitor: " + battery_status)
      if "Discharging" in battery_status:
          percent = int( backtick("acpi -b | awk '{print $4}' | tr -d '%,'"))
          if percent < 5:
              print("power-monitor: check-battery: systemctl hibernate")
              os.system("pkill battery-alarm; sudo systemctl hibernate")
          if percent < 10:
              print("power-monitor: check-battery: battery-alarm")
              os.system("battery-alarm&")
      gobject.timeout_add(60 * 1000, check_battery)
  
  # get path from 'upower -e':
  bus.add_signal_receiver(ac, signal_name="PropertiesChanged", dbus_interface="org.freedesktop.DBus.Properties", path="/org/freedesktop/UPower/devices/line_power_ADP0")
  
  check_battery()
  
  l = gobject.MainLoop()
  l.run()
  
Put this in ''$HOME/bin/low-power'':

  #!/usr/bin/env bash 
  
  POWER="OFF"
  [[ "${1:-}" && "$1" == "false" ]] && POWER="ON"
  
  echo "$0: POWER=$POWER"
  
  case "$POWER" in
      OFF)
          battery-status
  
          #sudo $( which 01-pm-power-display) true
          sudo $( which brightness ) 20
          sudo $( which 02-pm-power-tweaks) true
          sudo $( which 03-pm-power-hda) true
  
          sudo powertop --auto-tune
          sleep 3
  
          battery-status
          ;;
      ON)
          #sudo $( which 01-pm-power-display) false
          sudo $( which brightness ) 100
          sudo $( which 02-pm-power-tweaks) false
          sudo $( which 03-pm-power-hda) false
          ;;
  esac
  
  pkill -0 i3blocks && pkill  -RTMIN+9 i3blocks
      
Put this in ''$HOME/bin/03-pm-power-hda'' to maximise battery or performance on the hard disc:

  #!/bin/sh
  logger -t $0 "$0 $@"
  
  case "$1" in
          true)
                  # called by pm-powersave on power disconnect
                  logger -t $0 "power disconnect: hdparm -B1 -S5 /dev/sda"
                  hdparm -B1 -S5 /dev/sda
                  ;;
          false)
                  # called by pm-powersave on power connect
                  logger -t $0 "power connect: hdparm -B128 -S60 /dev/sda"
                  hdparm -B128 -S60 /dev/sda
                  ;;
  esac
  exit 0

Put this in ''$HOME/bin/02-pm-power-tweaks'' for general tweaking - most of this originates from ''powertop'':

  #!/usr/bin/env bash
  # BH
  
  logger -t $0 "$0 $@"
  case "$1" in
  true)
      logger -t $0 "power disconnect"
      systemctl stop bluetooth.target
      rfkill block bluetooth
      BT_PID=$(ps -ef |grep '[/]usr/libexec/bluetooth/bluetoothd' | awk '{print $2}')
      [[ "$BT_PID" ]] && kill -9 $BT_PID
  
      echo 5 > /proc/sys/vm/laptop_mode
      echo 0 > /proc/sys/kernel/nmi_watchdog
      # echo 1 > /sys/devices/system/cpu/sched_smt_power_savings
      echo powersave > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
      echo 1500 > /proc/sys/vm/dirty_writeback_centisecs
      for i in /sys/bus/usb/devices/*/power/autosuspend; do echo 1 > $i; done
      for i in /sys/bus/usb/devices/*/power/level; do echo auto > $i; done
      echo min_power > /sys/class/scsi_host/host0/link_power_management_policy
      echo min_power > /sys/class/scsi_host/host1/link_power_management_policy
      echo Y > /sys/module/snd_hda_intel/parameters/power_save_controller
      echo 1 > /sys/module/snd_hda_intel/parameters/power_save
      for i in /sys/bus/pci/devices/*/power/control; do echo auto > $i; done
      iw dev wlp3s0 set power_save on
      ;;
  false)
      logger -t $0 "power connect"
      echo 0 > /proc/sys/vm/laptop_mode
      echo 1 > /proc/sys/kernel/nmi_watchdog
      # echo 0 > /sys/devices/system/cpu/sched_smt_power_savings
      echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
      echo 500 > /proc/sys/vm/dirty_writeback_centisecs
      for i in /sys/bus/usb/devices/*/power/autosuspend; do echo 2 > $i; done
      # for i in /sys/bus/usb/devices/*/power/level; do echo auto > $i; done
      echo max_performance > /sys/class/scsi_host/host0/link_power_management_policy
      echo max_performance > /sys/class/scsi_host/host1/link_power_management_policy
      #echo Y > /sys/module/snd_hda_intel/parameters/power_save_controller
      #echo 1 > /sys/module/snd_hda_intel/parameters/power_save
      #for i in /sys/bus/pci/devices/*/power/control; do echo auto > $i; done
  
      modprobe bluetooth
      rfkill unblock bluetooth
  
      systemctl start bluetooth.target
  
      modprobe uvcvideo r8169 mii
      iw dev wlp3s0 set power_save off
      ;;
  esac
  
  exit 0
  
To run stuff on 'resume', put this in ''/etc/systemd/system/bhepple-resume.service'':

  [Unit]
  Description=Run on 'resume'
  After=suspend.target
  
  [Service]
  User=root
  Type=oneshot
  ExecStart=/sbin/hdparm -y /dev/sda # puts aux disc into standby - should test that it's not '/' !!
  
  [Install]
  WantedBy=suspend.target

and run ''systemctl enable bhepple-resume.service''

brightness is this:

  #!/bin/bash
  
  # since xbacklight isn't working (nouveau?)
  # https://bbs.archlinux.org/viewtopic.php?id=134972 and modified:
  
  # needs to be run as root
  
  NEW_VALUE=${1:-0}
  
  # base dir for backlight class
  basedir="/sys/class/backlight/"
  
  # get the backlight handler
  handler=$basedir$(ls $basedir |head -n 1)"/"
  
  # get current brightness
  old_brightness=$(cat $handler"brightness")
  
  # get max brightness
  max_brightness=$(cat $handler"max_brightness")
  
  # get current brightness %
  old_brightness_p=$(( 100 * $old_brightness / $max_brightness ))
  
  # calculate new brightness %
  if [[ $NEW_VALUE == [+-]* ]]; then
      new_brightness_p=$(($old_brightness_p + $NEW_VALUE))
  else
      new_brightness_p=$NEW_VALUE
  fi
  
  # calculate new brightness value
  new_brightness=$(( $max_brightness * $new_brightness_p / 100 ))
  
  (( new_brightness <= max_brightness && new_brightness >= 0 )) && {
      # set the new brightness value
      echo $new_brightness > $handler"brightness"
  }
  
====Disable nouveau====

I find it slow & buggy so ''/etc/modprobe.d/blacklist.conf'' gets:

  blacklist nouveau
  
and ''/etc/default/grub'' gets:

  rdblacklist=nouveau
  
Run this to get grub updated:

  grub2-mkconfig >/boot/grub2/grub.cfg