[ALSA] usb-audio: add Audigy 2 NX control names

USB generic driver
Add a mixer control map for the SB Audigy 2 NX so
that we get meaningful mixer control names.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
diff --git a/sound/usb/usbmixer_maps.c b/sound/usb/usbmixer_maps.c
index 1e994c9..4918a18 100644
--- a/sound/usb/usbmixer_maps.c
+++ b/sound/usb/usbmixer_maps.c
@@ -118,6 +118,50 @@
 	{ 0 } /* terminator */
 };
 
+/* Topology of SB Audigy 2 NX
+
+          +----------------------------->EU[27]--+
+          |                                      v
+          | +----------------------------------->SU[29]---->FU[22]-->Dig_OUT[24]
+          | |                                    ^
+USB_IN[1]-+------------+              +->EU[17]->+->FU[11]-+
+            |          v              |          v         |
+Dig_IN[4]---+->FU[6]-->MU[16]->FU[18]-+->EU[21]->SU[31]----->FU[30]->Hph_OUT[20]
+            |          ^              |                    |
+Lin_IN[7]-+--->FU[8]---+              +->EU[23]->FU[28]------------->Spk_OUT[19]
+          | |                                              v
+          +--->FU[12]------------------------------------->SU[14]--->USB_OUT[15]
+            |                                              ^
+            +->FU[13]--------------------------------------+
+*/
+static struct usbmix_name_map audigy2nx_map[] = {
+	/* 1: IT pcm playback */
+	/* 4: IT digital in */
+	{ 6, "Digital In Playback" }, /* FU */
+	/* 7: IT line in */
+	{ 8, "Line Playback" }, /* FU */
+	{ 11, "What-U-Hear Capture" }, /* FU */
+	{ 12, "Line Capture" }, /* FU */
+	{ 13, "Digital In Capture" }, /* FU */
+	{ 14, "Capture Source" }, /* SU */
+	/* 15: OT pcm capture */
+	/* 16: MU w/o controls */
+	{ 17, NULL }, /* DISABLED: EU (for what?) */
+	{ 18, "Master Playback" }, /* FU */
+	/* 19: OT speaker */
+	/* 20: OT headphone */
+	{ 21, NULL }, /* DISABLED: EU (for what?) */
+	{ 22, "Digital Out Playback" }, /* FU */
+	{ 23, NULL }, /* DISABLED: EU (for what?) */
+	/* 24: OT digital out */
+	{ 27, NULL }, /* DISABLED: EU (for what?) */
+	{ 28, "Speaker Playback" }, /* FU */
+	{ 29, "Digital Out Source" }, /* SU */
+	{ 30, "Headphone Playback" }, /* FU */
+	{ 31, "Headphone Source" }, /* SU */
+	{ 0 } /* terminator */
+};
+
 /* LineX FM Transmitter entry - needed to bypass controls bug */
 static struct usbmix_name_map linex_map[] = {
 	/* 1: IT pcm */
@@ -156,6 +200,7 @@
 static struct usbmix_ctl_map usbmix_ctl_maps[] = {
 	{ 0x41e, 0x3000, extigy_map, 1 },
 	{ 0x41e, 0x3010, mp3plus_map, 0 },
+	{ 0x41e, 0x3020, audigy2nx_map, 0 },
 	{ 0x8bb, 0x2702, linex_map, 1 },
 	{ 0xc45, 0x1158, justlink_map, 0 },
 	{ 0 } /* terminator */