ALSA: hda - Modularize HD-audio driver

Split the monolithc HD-audio driver into several pieces:
 - snd-hda-intel   HD-audio PCI controller driver; loaded via udev
 - snd-hda-codec   HD-audio codec bus driver
 - snd-hda-codec-* Specific HD-audio codec drivers

When built as modules, snd-hda-codec (that is invoked by snd-hda-intel)
looks up the codec vendor ID and loads the corresponding codec module
automatically via request_module().

When built in a kernel, each codec drivers are statically hooked up
before probing the PCI.

This patch adds appropriate EXPORT_SYMBOL_GPL()'s and the module
information for each driver, and driver-linking codes between
codec-bus and codec drivers.

TODO:
  - Avoid EXPORT_SYMBOL*() when built-in kernel
  - Restore __devinit appropriately depending on the condition

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/patch_sigmatel.c b/sound/pci/hda/patch_sigmatel.c
index 70181d50..9e07f44 100644
--- a/sound/pci/hda/patch_sigmatel.c
+++ b/sound/pci/hda/patch_sigmatel.c
@@ -33,7 +33,6 @@
 #include <sound/jack.h>
 #include "hda_codec.h"
 #include "hda_local.h"
-#include "hda_patch.h"
 #include "hda_beep.h"
 
 enum {
@@ -5455,7 +5454,7 @@
 /*
  * patch entries
  */
-struct hda_codec_preset snd_hda_preset_sigmatel[] = {
+static struct hda_codec_preset snd_hda_preset_sigmatel[] = {
  	{ .id = 0x83847690, .name = "STAC9200", .patch = patch_stac9200 },
  	{ .id = 0x83847882, .name = "STAC9220 A1", .patch = patch_stac922x },
  	{ .id = 0x83847680, .name = "STAC9221 A1", .patch = patch_stac922x },
@@ -5519,3 +5518,27 @@
 	{ .id = 0x111d76b7, .name = "92HD71B5X", .patch = patch_stac92hd71bxx },
 	{} /* terminator */
 };
+
+MODULE_ALIAS("snd-hda-codec-id:8384*");
+MODULE_ALIAS("snd-hda-codec-id:111d*");
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("IDT/Sigmatel HD-audio codec");
+
+static struct hda_codec_preset_list sigmatel_list = {
+	.preset = snd_hda_preset_sigmatel,
+	.owner = THIS_MODULE,
+};
+
+static int __init patch_sigmatel_init(void)
+{
+	return snd_hda_add_codec_preset(&sigmatel_list);
+}
+
+static void __exit patch_sigmatel_exit(void)
+{
+	snd_hda_delete_codec_preset(&sigmatel_list);
+}
+
+module_init(patch_sigmatel_init)
+module_exit(patch_sigmatel_exit)