[ALSA] Add Native Instrument usb audio device support

Add snd-usb-caiaq driver to support caiaq usb-audio devices from
Native Instrument:
	* Native Instruments RigKontrol2
	* Native Instruments Kore Controller
	* Native Instruments Audio Kontrol 1
	* Native Instruments Audio 8 DJ

Signed-off-by: Daniel Mack <daniel@caiaq.org>
Signed-off-by: Karsten Wiese <fzu@wemgehoertderstaat.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/usb/caiaq/caiaq-midi.c b/sound/usb/caiaq/caiaq-midi.c
new file mode 100644
index 0000000..793ca20
--- /dev/null
+++ b/sound/usb/caiaq/caiaq-midi.c
@@ -0,0 +1,177 @@
+/*
+ *   Copyright (c) 2006,2007 Daniel Mack
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+*/
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/interrupt.h>
+#include <linux/usb.h>
+#include <linux/input.h>
+#include <linux/spinlock.h>
+#include <sound/driver.h>
+#include <sound/core.h>
+#include <sound/rawmidi.h>
+#include <sound/pcm.h>
+
+#include "caiaq-device.h"
+#include "caiaq-midi.h"
+
+
+static int snd_usb_caiaq_midi_input_open(struct snd_rawmidi_substream *substream)
+{
+	return 0;
+}
+
+static int snd_usb_caiaq_midi_input_close(struct snd_rawmidi_substream *substream)
+{
+	return 0;
+}
+
+static void snd_usb_caiaq_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
+{
+	struct snd_usb_caiaqdev *dev = substream->rmidi->private_data;
+
+	if (!dev)
+		return;
+	
+	dev->midi_receive_substream = up ? substream : NULL;
+}
+
+
+static int snd_usb_caiaq_midi_output_open(struct snd_rawmidi_substream *substream)
+{
+	return 0;
+}
+
+static int snd_usb_caiaq_midi_output_close(struct snd_rawmidi_substream *substream)
+{
+	return 0;
+}
+
+static void snd_usb_caiaq_midi_send(struct snd_usb_caiaqdev *dev,
+				    struct snd_rawmidi_substream *substream)
+{
+	int len, ret;
+	
+	dev->midi_out_buf[0] = EP1_CMD_MIDI_WRITE;
+	dev->midi_out_buf[1] = 0; /* port */
+	len = snd_rawmidi_transmit_peek(substream, dev->midi_out_buf+3, EP1_BUFSIZE-3);
+	
+	if (len <= 0)
+		return;
+	
+	dev->midi_out_buf[2] = len;
+	dev->midi_out_urb.transfer_buffer_length = len+3;
+	
+	ret = usb_submit_urb(&dev->midi_out_urb, GFP_ATOMIC);
+	if (ret < 0)
+		log("snd_usb_caiaq_midi_send(%p): usb_submit_urb() failed, %d\n",
+				substream, ret);
+}
+
+static void snd_usb_caiaq_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
+{
+	struct snd_usb_caiaqdev *dev = substream->rmidi->private_data;
+	
+	if (dev->midi_out_substream != NULL)
+		return;
+	
+	if (!up) {
+		dev->midi_out_substream = NULL;
+		return;
+	}
+	
+	dev->midi_out_substream = substream;
+	snd_usb_caiaq_midi_send(dev, substream);
+}
+
+
+static struct snd_rawmidi_ops snd_usb_caiaq_midi_output =
+{
+	.open =		snd_usb_caiaq_midi_output_open,
+	.close =	snd_usb_caiaq_midi_output_close,
+	.trigger =      snd_usb_caiaq_midi_output_trigger,
+};
+
+static struct snd_rawmidi_ops snd_usb_caiaq_midi_input =
+{
+	.open =		snd_usb_caiaq_midi_input_open,
+	.close =	snd_usb_caiaq_midi_input_close,
+	.trigger =      snd_usb_caiaq_midi_input_trigger,
+};
+
+void snd_usb_caiaq_midi_handle_input(struct snd_usb_caiaqdev *dev, 
+				     int port, const char *buf, int len)
+{
+	if (!dev->midi_receive_substream)
+		return;
+	
+	snd_rawmidi_receive(dev->midi_receive_substream, buf, len);
+}
+
+int __devinit snd_usb_caiaq_midi_init(struct snd_usb_caiaqdev *device)
+{
+	int ret;
+	struct snd_rawmidi *rmidi;
+
+	ret = snd_rawmidi_new(device->chip.card, device->product_name, 0,
+					device->spec.num_midi_out,
+					device->spec.num_midi_in,
+					&rmidi);
+
+	if (ret < 0)
+		return ret;
+
+	strcpy(rmidi->name, device->product_name);
+
+	rmidi->info_flags = SNDRV_RAWMIDI_INFO_DUPLEX;
+	rmidi->private_data = device;
+
+	if (device->spec.num_midi_out > 0) {
+		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
+		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, 
+				    &snd_usb_caiaq_midi_output);
+	}
+
+	if (device->spec.num_midi_in > 0) {
+		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
+		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, 
+				    &snd_usb_caiaq_midi_input);
+	}
+	
+	device->rmidi = rmidi;
+
+	return 0;
+}
+
+void snd_usb_caiaq_midi_output_done(struct urb* urb)
+{
+	struct snd_usb_caiaqdev *dev = urb->context;
+      	char *buf = urb->transfer_buffer;
+	
+	if (urb->status != 0)
+		return;
+
+	if (!dev->midi_out_substream)
+		return;
+
+	snd_rawmidi_transmit_ack(dev->midi_out_substream, buf[2]);
+	dev->midi_out_substream = NULL;
+	snd_usb_caiaq_midi_send(dev, dev->midi_out_substream);
+}
+