uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

nixos/modules/services/hardware/sane.nix

@@ -0,0 +1,197 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  pkg = pkgs.sane-backends.override {
+    scanSnapDriversUnfree = config.hardware.sane.drivers.scanSnap.enable;
+    scanSnapDriversPackage = config.hardware.sane.drivers.scanSnap.package;
+  };
+
+  sanedConf = pkgs.writeTextFile {
+    name = "saned.conf";
+    destination = "/etc/sane.d/saned.conf";
+    text = ''
+      localhost
+      ${config.services.saned.extraConfig}
+    '';
+  };
+
+  netConf = pkgs.writeTextFile {
+    name = "net.conf";
+    destination = "/etc/sane.d/net.conf";
+    text = ''
+      ${lib.optionalString config.services.saned.enable "localhost"}
+      ${config.hardware.sane.netConf}
+    '';
+  };
+
+  env = {
+    SANE_CONFIG_DIR = config.hardware.sane.configDir;
+    LD_LIBRARY_PATH = [ "${saneConfig}/lib/sane" ];
+  };
+
+  backends = [ pkg netConf ] ++ optional config.services.saned.enable sanedConf ++ config.hardware.sane.extraBackends;
+  saneConfig = pkgs.mkSaneConfig { paths = backends; inherit (config.hardware.sane) disabledDefaultBackends; };
+
+  enabled = config.hardware.sane.enable || config.services.saned.enable;
+
+in
+
+{
+
+  ###### interface
+
+  options = {
+
+    hardware.sane.enable = mkOption {
+      type = types.bool;
+      default = false;
+      description = ''
+        Enable support for SANE scanners.
+
+        <note><para>
+          Users in the "scanner" group will gain access to the scanner, or the "lp" group if it's also a printer.
+        </para></note>
+      '';
+    };
+
+    hardware.sane.snapshot = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Use a development snapshot of SANE scanner drivers.";
+    };
+
+    hardware.sane.extraBackends = mkOption {
+      type = types.listOf types.path;
+      default = [];
+      description = ''
+        Packages providing extra SANE backends to enable.
+
+        <note><para>
+          The example contains the package for HP scanners.
+        </para></note>
+      '';
+      example = literalExpression "[ pkgs.hplipWithPlugin ]";
+    };
+
+    hardware.sane.disabledDefaultBackends = mkOption {
+      type = types.listOf types.str;
+      default = [];
+      example = [ "v4l" ];
+      description = ''
+        Names of backends which are enabled by default but should be disabled.
+        See <literal>$SANE_CONFIG_DIR/dll.conf</literal> for the list of possible names.
+      '';
+    };
+
+    hardware.sane.configDir = mkOption {
+      type = types.str;
+      internal = true;
+      description = "The value of SANE_CONFIG_DIR.";
+    };
+
+    hardware.sane.netConf = mkOption {
+      type = types.lines;
+      default = "";
+      example = "192.168.0.16";
+      description = ''
+        Network hosts that should be probed for remote scanners.
+      '';
+    };
+
+    hardware.sane.drivers.scanSnap.enable = mkOption {
+      type = types.bool;
+      default = false;
+      example = true;
+      description = ''
+        Whether to enable drivers for the Fujitsu ScanSnap scanners.
+
+        The driver files are unfree and extracted from the Windows driver image.
+      '';
+    };
+
+    hardware.sane.drivers.scanSnap.package = mkOption {
+      type = types.package;
+      default = pkgs.sane-drivers.epjitsu;
+      defaultText = literalExpression "pkgs.sane-drivers.epjitsu";
+      description = ''
+        Epjitsu driver package to use. Useful if you want to extract the driver files yourself.
+
+        The process is described in the <literal>/etc/sane.d/epjitsu.conf</literal> file in
+        the <literal>sane-backends</literal> package.
+      '';
+    };
+
+    services.saned.enable = mkOption {
+      type = types.bool;
+      default = false;
+      description = ''
+        Enable saned network daemon for remote connection to scanners.
+
+        saned would be runned from <literal>scanner</literal> user; to allow
+        access to hardware that doesn't have <literal>scanner</literal> group
+        you should add needed groups to this user.
+      '';
+    };
+
+    services.saned.extraConfig = mkOption {
+      type = types.lines;
+      default = "";
+      example = "192.168.0.0/24";
+      description = ''
+        Extra saned configuration lines.
+      '';
+    };
+
+  };
+
+
+  ###### implementation
+
+  config = mkMerge [
+    (mkIf enabled {
+      hardware.sane.configDir = mkDefault "${saneConfig}/etc/sane.d";
+
+      environment.systemPackages = backends;
+      environment.sessionVariables = env;
+      services.udev.packages = backends;
+
+      users.groups.scanner.gid = config.ids.gids.scanner;
+    })
+
+    (mkIf config.services.saned.enable {
+      networking.firewall.connectionTrackingModules = [ "sane" ];
+
+      systemd.services."saned@" = {
+        description = "Scanner Service";
+        environment = mapAttrs (name: val: toString val) env;
+        serviceConfig = {
+          User = "scanner";
+          Group = "scanner";
+          ExecStart = "${pkg}/bin/saned";
+        };
+      };
+
+      systemd.sockets.saned = {
+        description = "saned incoming socket";
+        wantedBy = [ "sockets.target" ];
+        listenStreams = [ "0.0.0.0:6566" "[::]:6566" ];
+        socketConfig = {
+          # saned needs to distinguish between IPv4 and IPv6 to open matching data sockets.
+          BindIPv6Only = "ipv6-only";
+          Accept = true;
+          MaxConnections = 64;
+        };
+      };
+
+      users.users.scanner = {
+        uid = config.ids.uids.scanner;
+        group = "scanner";
+        extraGroups = [ "lp" ] ++ optionals config.services.avahi.enable [ "avahi" ];
+      };
+    })
+  ];
+
+}