Disabling dGPU on Dell XPS 9560 on Ubuntu 16.10

disable-dgpu-xps9560-ubuntu-1610

# Tested with kernel: 4.9.20-040920-generic

#
# Make sure to install following packages
#
sudo apt install acpi acpi-call-dkms

#
# To manually disable, you can run the following command
#
echo '\_SB.PCI0.PEG0.PEGP._OFF' > /proc/acpi/call            # via root
echo '\_SB.PCI0.PEG0.PEGP._OFF' | sudo tee /proc/acpi/call    # via your own user

#
# To automate on startup, do the following: 
#
echo acpi_call > /etc/modules-load.d/acpi_call.conf

# Create /usr/lib/systemd/user/dgpu-off.service with the following contents:
  [Unit]
  Description=Power-off dGPU
  After=graphical.target

  [Service]
  Type=oneshot
  ExecStart=/bin/sh -c "echo '\\_SB.PCI0.PEG0.PEGP._OFF' > /proc/acpi/call"

  [Install]
  WantedBy=graphical.target

# Enable the new unit file
systemctl enable /usr/lib/systemd/user/dgpu-off.service