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/hardware/video/uvcvideo/default.nix

@@ -0,0 +1,64 @@
+
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  cfg = config.services.uvcvideo;
+
+  uvcdynctrl-udev-rules = packages: pkgs.callPackage ./uvcdynctrl-udev-rules.nix {
+    drivers = packages;
+    udevDebug = false;
+  };
+
+in
+
+{
+
+  options = {
+    services.uvcvideo.dynctrl = {
+
+      enable = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Whether to enable <command>uvcvideo</command> dynamic controls.
+
+          Note that enabling this brings the <command>uvcdynctrl</command> tool
+          into your environment and register all dynamic controls from
+          specified <command>packages</command> to the <command>uvcvideo</command> driver.
+        '';
+      };
+
+      packages = mkOption {
+        type = types.listOf types.path;
+        example = literalExpression "[ pkgs.tiscamera ]";
+        description = ''
+          List of packages containing <command>uvcvideo</command> dynamic controls
+          rules. All files found in
+          <filename><replaceable>pkg</replaceable>/share/uvcdynctrl/data</filename>
+          will be included.
+
+          Note that these will serve as input to the <command>libwebcam</command>
+          package which through its own <command>udev</command> rule will register
+          the dynamic controls from specified packages to the <command>uvcvideo</command>
+          driver.
+        '';
+        apply = map getBin;
+      };
+    };
+  };
+
+  config = mkIf cfg.dynctrl.enable {
+
+    services.udev.packages = [
+      (uvcdynctrl-udev-rules cfg.dynctrl.packages)
+    ];
+
+    environment.systemPackages = [
+      pkgs.libwebcam
+    ];
+
+  };
+}