xanecs · July 12, 2021 17:02 · Sep 30, 2016 · Sep 30, 2016 · Sep 30, 2016
diff --git a/elementaryOS_on_C720.md → _elementaryOS_on_C720.md b/elementaryOS_on_C720.md → _elementaryOS_on_C720.md
diff --git a/README.md → elementaryOS_on_C720.md b/README.md → elementaryOS_on_C720.md
diff --git a/README.md b/README.md
@@ -0,0 +1,129 @@
+This guide will show you how to install and configure elementaryOS Loki on your Acer C720 or C720p.
+I'm assuming you have installed some sort of Linux on your Chromebook before and already know your way around
+in Developer Mode. If not, read and follow
+https://www.chromium.org/chromium-os/developer-information-for-chrome-os-devices/acer-c720-chromebook sections
+"Developer Mode" and "Legacy Boot".
+
+# Installation
+Nothing special here: Download the ISO from https://elementary.io (put in $0 as an amount to download the ISO for free,
+although you should consider donating)
+
+Put in a USB drive, locate its device address (e. g. /dev/sdX on Linux, /dev/diskX on macOS).
+Then unmount it and use dd to write the iso to the drive:
+```bash
+sudo umount /dev/sdX #Linux
+sudo diskutil unmountDisk # macOS
+
+sudo dd if=Downloads/elementary.iso of=/dev/sdX bs=1M # Linux
+sudo dd if=Downloads/elementary.iso of=/dev/rdiskX bs=1m # macOS
+```
+
+After that's done, plug the drive into your Chromebook, turn it on, wait for the scary white screen, then press `CTRL + L`
+to enter the SeaBIOS, press ESC and the number corresponding to your USB drive.
+
+Click through the installer and reboot.
+
+# Fixing Chromebook specifics
+
+## Touchpad
+Surprisingly works well out of the box. Only "issue" is that you need to physically depress the touchpad to do a click.
+
+**To change this** go to **System Settings** > **Mouse & Touchpad** and enable **Tap to click**.
+
+## Suspend and Resume
+Will not work out of the box. To get it working, do the following:
+
+Edit `/etc/default/grub` and change *GRUB_CMDLINE_LINUX_DEFAULT* to
+
+```
+GRUB_CMDLINE_LINUX_DEFAULT="tpm_tis.force=1 quiet splash"
+```
+
+Download `ehci-pci.sh` from below, then move it to */lib/systemd/system-sleep/ehci-pci.sh*
+and change its access rights to *755*
+
+```bash
+sudo mv Downloas/ehci-pci.sh /lib/systemd/system-sleep/ehci-pci.sh
+sudo chmod 755 /lib/systemd/system-sleep/ehci-pci.sh
+```
+
+Next you'll want to prevent the Touchpad from waking up the system from sleep as the screen often accidentally
+presses against the touchpad and causes this.
+
+To do this download `disable-touchpad-wakeup.conf` from below and move it to */etc/tmpfiles.d/disable-touchpad-wakeup.conf*
+
+```bash
+sudo mv Downloads/disable-touchpad-wakeup.conf /etc/tmpfiles.d/disable-touchpad-wakeup.conf
+```
+
+## Power saving
+While elementaryOS is not bad at being a low-power distro it still leaves a lot of room for improvement.
+
+### Wifi Powersave
+Enable the powersave mode of the wifi card by downloading `ath9k.conf` from below and
+moving it to */etc/modprobe.d/ath9k.conf*
+
+```bash
+sudo mv Downloads/ath9k.conf /etc/modprobe.d/ath9k.conf
+```
+
+### Audio Powersave
+Tell the audio card to turn off after 1 second of silence.  
+Download `audio_powersave.conf` from below and move it to */etc/modprobe.d/audio_powersave.conf*
+
+```bash
+sudo mv Downloads/audio_powersave.conf /etc/modprobe.d/audio_powersave.conf
+```
+
+### NMI Watchdog
+Disable a kernel debugging feature.  
+
+Download `disable_watchdog.conf` from below and move it to */etc/sysctl.d/disable_watchdog.conf*
+
+```bash
+sudo mv Downloads/disable_watchdog.conf /etc/sysctl.d/disable_watchdog.conf
+```
+
+### Dirty Writeback
+Write to disk less often
+
+Download `dirty.conf` from below and move it to */etc/sysctl.d/dirty.conf*
+
+```bash
+sudo mv Downloads/dirty.conf /etc/sysctl.d/dirty.conf
+```
+
+### Laptop mode
+Queue disk writes over several seconds, write them at once, then turn of the SSD.
+This is potentially risky, as the higher you set this setting, the more seconds of work you may loose in case of a
+system crash. Most people recommend a setting of about 5 (meaning 5 seconds) but you can turn this up to 5 minutes or more.
+When the battery is low, this setting will be overridden, so no danger here.
+
+Download `laptop.conf` from below and move it to */etc/sysctl.d/laptop.conf*
+
+```bash
+sudo mv Downloads/laptop.conf /etc/sysctl.d/laptop.conf
+```
+
+### SATA Power management
+**WARNING** This feature will cause issues if you have fitted your chromebook with a *Transcend* SSD.
+These contain a firmware bug that will cause your chromebook to freeze or crash if it puts the SATA interface into low power
+mode. If you have one of those SSDs, skip this step.
+
+Download `hd_powersave.conf` from below and move it to */etc/udev/rules.d/hd_powersave.conf*
+
+```bash
+sudo mv Downloads/hd_powersave.conf /etc/udev/rules.d/hd_powersave.conf
+```
+
+### PCI Power management
+
+Download `pci_powersave.conf` from below and move it to */etc/udev/rules.d/pci_powersave.conf*
+
+```bash
+sudo mv Downloads/pci_powersave.conf /etc/udev/rules.d/pci_powersave.conf
+```
+
+---
+
+Now reboot and you should be good to go.
diff --git a/ath9k.conf b/ath9k.conf
@@ -0,0 +1,4 @@
+options ath9k btcoex_enable=1 ps_enable=1
+
+# If you don't need bluetooth change this to
+# options ath9k ps_enable=1 bluetooth_ant_diversity=1
diff --git a/audio_powersave.conf b/audio_powersave.conf
@@ -0,0 +1 @@
+options snd_hda_intel power_save=1
diff --git a/dirty.conf b/dirty.conf
@@ -0,0 +1 @@
+vm.dirty_writeback_centisecs = 1500
diff --git a/disable-touchpad-wakeup.conf b/disable-touchpad-wakeup.conf
@@ -0,0 +1 @@
+w /proc/acpi/wakeup - - - - TPAD
diff --git a/disable_watchdog.conf b/disable_watchdog.conf
@@ -0,0 +1 @@
+kernel.nmi_watchdog = 0
diff --git a/ehci-pci.sh b/ehci-pci.sh
@@ -0,0 +1,15 @@
+#!/bin/bash
+
+# Place into /lib/systemd/system-sleep/ehci-pci.sh 
+#
+# Change access rights to 755:
+# sudo chmod 755 /lib/systemd/system-sleep/ehci-pci.sh
+
+case $1/$2 in
+        pre/*)
+        echo -n "0000:00:1d.0" | tee /sys/bus/pci/drivers/ehci-pci/unbind
+        ;;
+        post/*)
+        echo -n "0000:00:1d.0" | tee /sys/bus/pci/drivers/ehci-pci/bind
+        ;;
+esac
diff --git a/hd_powersave.conf b/hd_powersave.conf
@@ -0,0 +1 @@
+ACTION=="add", SUBSYSTEM=="scsi_host", KERNEL=="host*", ATTR{link_power_management_policy}="min_power"
diff --git a/laptop.conf b/laptop.conf
@@ -0,0 +1 @@
+vm.laptop_mode=5
diff --git a/pci_powersave.conf b/pci_powersave.conf
@@ -0,0 +1 @@
+ACTION=="add", SUBSYSTEM=="pci", ATTR{power/control}="auto"
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		ACTION=="add", SUBSYSTEM=="scsi_host", KERNEL=="host*", ATTR{link_power_management_policy}="min_power"
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		ACTION=="add", SUBSYSTEM=="pci", ATTR{power/control}="auto"