remote-display-pi/configuration.nix

{ hardware, stable, config, pkgs, lib, ... }:

let
  interface = "wlan0";
  hostname = "nixpi";
in {
  time.timeZone = "Europe/Berlin";

  # Select internationalisation properties.
  i18n.defaultLocale = "en_US.UTF-8";

  i18n.extraLocaleSettings = {
    LC_ADDRESS = "de_DE.UTF-8";
    LC_IDENTIFICATION = "de_DE.UTF-8";
    LC_MEASUREMENT = "de_DE.UTF-8";
    LC_MONETARY = "de_DE.UTF-8";
    LC_NAME = "de_DE.UTF-8";
    LC_NUMERIC = "de_DE.UTF-8";
    LC_PAPER = "de_DE.UTF-8";
    LC_TELEPHONE = "de_DE.UTF-8";
    LC_TIME = "de_DE.UTF-8";
  };

  sound.enable = true;
  hardware.pulseaudio.enable = true;

  # Create gpio group
  users.groups.gpio = {};

  # Change permissions gpio devices
  services.udev.extraRules = ''
    SUBSYSTEM=="bcm2835-gpiomem", KERNEL=="gpiomem", GROUP="gpio",MODE="0660"
    SUBSYSTEM=="gpio", KERNEL=="gpiochip*", ACTION=="add", RUN+="${pkgs.bash}/bin/bash -c 'chown root:gpio  /sys/class/gpio/export /sys/class/gpio/unexport ; chmod 220 /sys/class/gpio/export /sys/class/gpio/unexport'"
    SUBSYSTEM=="gpio", KERNEL=="gpio*", ACTION=="add",RUN+="${pkgs.bash}/bin/bash -c 'chown root:gpio /sys%p/active_low /sys%p/direction /sys%p/edge /sys%p/value ; chmod 660 /sys%p/active_low /sys%p/direction /sys%p/edge /sys%p/value'"
    SUBSYSTEM=="spidev", KERNEL=="spidev0.0", GROUP="spi", MODE="0660"
  '';

  hardware = {
    raspberry-pi."4" = {
#      audio.enable = true;
      apply-overlays-dtmerge.enable = true;
    };
    deviceTree = {
      enable = true;
      filter = "*rpi-4-*.dtb";
      overlays = [
        {
          name = "spi";
          dtboFile = ./spi0-0cs.dtbo;
        }
      ];
    };
  };

  users.groups.spi = {};

  console.keyMap = "de";

  services.xserver = {
    layout = "de";
    displayManager.startx.enable = true;
    xkbVariant = "";
    videoDrivers = [ "fbdev" ];
    enable = true;
  };


  boot = {
    kernelPackages = pkgs.linuxKernel.packages.linux_rpi4;
    kernelParams = [ "quiet" ];

    initrd.availableKernelModules = [ "xhci_pci" "usbhid" "usb_storage" ];
    loader = {
      grub.enable = false;
      generic-extlinux-compatible.enable = true;
    };
  };

  fileSystems = {
    "/" = {
      device = "/dev/disk/by-label/NIXOS_SD";
      fsType = "ext4";
      options = [ "noatime" ];
    };
  };

  networking = {
    hostName = hostname;
    wireless = {
      enable = true;
      userControlled.enable = false;
      networks = (import ./networks.nix);
      interfaces = [ interface ];
    };
  };

  services.openssh.enable = true;

  programs.xonsh.enable = true;
  users = {
    mutableUsers = false;
    users."pi" = {
      shell = pkgs.xonsh;
      isNormalUser = true;
      hashedPassword = "$y$j9T$ODBtPwWjIx50Bjhctw9kW/$jhfsHaAyh8zOXBV7cCK9l2M0yWyE3VLiL0h55XXV5J2";
      extraGroups = [ "wheel" "gpio" "spi" "dialout" ];
      openssh.authorizedKeys.keys = (import ./authorizedKeys.nix);
    };
  };

  hardware.enableRedistributableFirmware = true;
  system.stateVersion = "23.11";
  hardware.bluetooth.enable = false;

  environment.systemPackages = with pkgs; [
    wget
    hyfetch
    usbutils
    pciutils
    lm_sensors
    btop
    file
    raspberrypi-eeprom
    libraspberrypi
    xorg.xinit
    xorg.xorgserver
    xorg.xf86inputevdev
    xorg.xf86inputsynaptics
    xorg.xf86inputlibinput
    xorg.xf86videofbdev
    tigervnc
    jq
    (writeShellScriptBin "connectvnc" "startx `which vncviewer` -fullscreen -viewonly grimmauld-nixos:5900 -passwd /root/.vnc/passwd --") # fixme: change address
  ];

  hardware.opengl.enable = true;
  hardware.opengl.driSupport = true;

  nix.settings.experimental-features = [ "nix-command" "flakes" ];
  nixpkgs.config.allowUnfree = true;

  boot.tmp.cleanOnBoot = true;
  zramSwap.enable = true;
}