From ba5655198654bcf65ee6d13f4b5f34786ca6a26e Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Thu, 1 Mar 2007 00:36:00 +0000
Subject: [PATCH] * ALSA support: save/restore the volume settings, create
 device nodes   in /dev/snd.

svn path=/nixos/trunk/; revision=8124
---
 system/options.nix                    |  9 +++++++
 system/system.nix                     |  3 ++-
 system/upstart.nix                    |  6 +++++
 upstart-jobs/alsa.nix                 | 38 +++++++++++++++++++++++++++
 upstart-jobs/udev-rules/50-udev.rules |  9 +++++++
 5 files changed, 64 insertions(+), 1 deletion(-)
 create mode 100644 upstart-jobs/alsa.nix

diff --git a/system/options.nix b/system/options.nix
index 8987ab2969a..b422815c33f 100644
--- a/system/options.nix
+++ b/system/options.nix
@@ -749,4 +749,13 @@
   }
 
   
+  {
+    name = ["sound" "enable"];
+    default = true;
+    description = "
+      Whether to enable ALSA sound.
+    ";
+  }
+
+  
 ]
diff --git a/system/system.nix b/system/system.nix
index b68ca907032..e032bad07ab 100644
--- a/system/system.nix
+++ b/system/system.nix
@@ -197,7 +197,8 @@ rec {
     nixosRebuild
     nixosCheckout
     setuidWrapper
-  ];
+  ]
+  ++ (if config.get ["sound" "enable"] then [pkgs.alsaUtils] else []);
 
 
   # We don't want to put all of `startPath' and `path' in $PATH, since
diff --git a/system/upstart.nix b/system/upstart.nix
index 7cd384ede53..3fa061e41c4 100644
--- a/system/upstart.nix
+++ b/system/upstart.nix
@@ -131,6 +131,12 @@ import ../upstart-jobs/gather.nix {
       inherit (pkgs) glibc pwdutils;
     })
 
+  # ALSA sound support.
+  ++ optional ["sound" "enable"]
+    (import ../upstart-jobs/alsa.nix {
+      inherit (pkgs) kernel module_init_tools alsaUtils;
+    })
+
   # Handles the reboot/halt events.
   ++ (map
     (event: makeJob (import ../upstart-jobs/halt.nix {
diff --git a/upstart-jobs/alsa.nix b/upstart-jobs/alsa.nix
new file mode 100644
index 00000000000..620401de914
--- /dev/null
+++ b/upstart-jobs/alsa.nix
@@ -0,0 +1,38 @@
+{kernel, module_init_tools, alsaUtils}:
+
+let
+
+  soundState = "/var/state/asound.state";
+
+in
+  
+{
+  name = "alsa";
+  
+  job = "
+start on hardware-scan
+stop on shutdown
+
+script
+
+    # Load some additional modules.
+    export MODULE_DIR=${kernel}/lib/modules/
+    for mod in snd_pcm_oss; do
+        ${module_init_tools}/sbin/modprobe $mod || true
+    done
+
+    # Restore the sound state.
+    ${alsaUtils}/sbin/alsactl -f ${soundState} restore
+
+end script
+
+stop script
+
+    # Save the sound state.
+    ${alsaUtils}/sbin/alsactl -f ${soundState} store
+
+end script
+
+  ";
+
+}
diff --git a/upstart-jobs/udev-rules/50-udev.rules b/upstart-jobs/udev-rules/50-udev.rules
index ff2ed86888b..a4f1d73250a 100644
--- a/upstart-jobs/udev-rules/50-udev.rules
+++ b/upstart-jobs/udev-rules/50-udev.rules
@@ -28,3 +28,12 @@ KERNEL=="uinput",               NAME="input/%k", MODE="0600"
 
 # Create a symlink for the CD-ROM device.
 KERNEL=="hd[a-z]", BUS=="ide", SYSFS{removable}=="1", SYSFS{device/media}=="cdrom", SYMLINK+="cdrom cdrom-%k"
+
+
+# ALSA sound devices.
+KERNEL=="controlC[0-9]*",       NAME="snd/%k"
+KERNEL=="hwC[D0-9]*",           NAME="snd/%k"
+KERNEL=="pcmC[D0-9cp]*",        NAME="snd/%k"
+KERNEL=="midiC[D0-9]*",         NAME="snd/%k"
+KERNEL=="timer",                NAME="snd/%k"
+KERNEL=="seq",                  NAME="snd/%k"