nixos/uvcvideo.dynctrl: Init

2 files changed, 110 insertions, 0 deletions

diff --git a/nixos/modules/hardware/video/uvcvideo/default.nix b/nixos/modules/hardware/video/uvcvideo/default.nix
new file mode 100644
index 000000000000..7e3e94fdf2bd
--- /dev/null
+++ b/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 environement and register all dynamic controls from
+          specified <command>packages</command> to the <command>uvcvideo</command> driver.
+        '';
+      };
+
+      packages = mkOption {
+        type = types.listOf types.path;
+        example = literalExample "[ 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
+    ];
+
+  };
+}
diff --git a/nixos/modules/hardware/video/uvcvideo/uvcdynctrl-udev-rules.nix b/nixos/modules/hardware/video/uvcvideo/uvcdynctrl-udev-rules.nix
new file mode 100644
index 000000000000..832e61966120
--- /dev/null
+++ b/nixos/modules/hardware/video/uvcvideo/uvcdynctrl-udev-rules.nix
@@ -0,0 +1,46 @@
+{ lib
+, stdenv
+, buildEnv
+, libwebcam
+, makeWrapper
+, runCommand
+, drivers ? []
+, udevDebug ? false
+}:
+
+let
+  version = "0.0.0";
+
+  dataPath = buildEnv {
+    name = "uvcdynctrl-with-drivers-data-path";
+    paths = drivers ++ [ libwebcam ];
+    pathsToLink = [ "/share/uvcdynctrl/data" ];
+    ignoreCollisions = false;
+  };
+
+  dataDir = "${dataPath}/share/uvcdynctrl/data";
+  udevDebugVarValue = if udevDebug then "1" else "0";
+in
+
+runCommand "uvcdynctrl-udev-rules-${version}"
+{
+  inherit dataPath;
+  buildInputs = [
+    makeWrapper
+    libwebcam
+  ];
+  dontPatchELF = true;
+  dontStrip = true;
+}
+''
+  mkdir -p "$out/lib/udev"
+  makeWrapper "${libwebcam}/lib/udev/uvcdynctrl" "$out/lib/udev/uvcdynctrl" \
+    --set NIX_UVCDYNCTRL_DATA_DIR "${dataDir}" \
+    --set NIX_UVCDYNCTRL_UDEV_DEBUG "${udevDebugVarValue}"
+
+  mkdir -p "$out/lib/udev/rules.d"
+  cat "${libwebcam}/lib/udev/rules.d/80-uvcdynctrl.rules" | \
+    sed -r "s#RUN\+\=\"([^\"]+)\"#RUN\+\=\"$out/lib/udev/uvcdynctrl\"#g" > \
+    "$out/lib/udev/rules.d/80-uvcdynctrl.rules"
+''
+