ALSA: usb-audio: header file cleanups

Rename snd-usb-lib to snd-usbmidi-lib as MIDI functions are the only
thing it actually contains. Introduce a new header file to only declare
these functions.

Introduced usbmixer.h for all functions exported by usbmixer.c.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/usbmidi.h b/sound/usb/usbmidi.h
new file mode 100644
index 0000000..2089ec9
--- /dev/null
+++ b/sound/usb/usbmidi.h
@@ -0,0 +1,48 @@
+#ifndef __USBMIDI_H
+#define __USBMIDI_H
+
+/* maximum number of endpoints per interface */
+#define MIDI_MAX_ENDPOINTS 2
+
+/* data for QUIRK_MIDI_FIXED_ENDPOINT */
+struct snd_usb_midi_endpoint_info {
+	int8_t   out_ep;	/* ep number, 0 autodetect */
+	uint8_t  out_interval;	/* interval for interrupt endpoints */
+	int8_t   in_ep;
+	uint8_t  in_interval;
+	uint16_t out_cables;	/* bitmask */
+	uint16_t in_cables;	/* bitmask */
+};
+
+/* for QUIRK_MIDI_YAMAHA, data is NULL */
+
+/* for QUIRK_MIDI_MIDIMAN, data points to a snd_usb_midi_endpoint_info
+ * structure (out_cables and in_cables only) */
+
+/* for QUIRK_COMPOSITE, data points to an array of snd_usb_audio_quirk
+ * structures, terminated with .ifnum = -1 */
+
+/* for QUIRK_AUDIO_FIXED_ENDPOINT, data points to an audioformat structure */
+
+/* for QUIRK_AUDIO/MIDI_STANDARD_INTERFACE, data is NULL */
+
+/* for QUIRK_AUDIO_EDIROL_UA700_UA25/UA1000, data is NULL */
+
+/* for QUIRK_IGNORE_INTERFACE, data is NULL */
+
+/* for QUIRK_MIDI_NOVATION and _RAW, data is NULL */
+
+/* for QUIRK_MIDI_EMAGIC, data points to a snd_usb_midi_endpoint_info
+ * structure (out_cables and in_cables only) */
+
+/* for QUIRK_MIDI_CME, data is NULL */
+
+int snd_usbmidi_create(struct snd_card *card,
+		       struct usb_interface *iface,
+		       struct list_head *midi_list,
+		       const struct snd_usb_audio_quirk *quirk);
+void snd_usbmidi_input_stop(struct list_head* p);
+void snd_usbmidi_input_start(struct list_head* p);
+void snd_usbmidi_disconnect(struct list_head *p);
+
+#endif /* __USBMIDI_H */