ALSA: usb/6fire - Driver for TerraTec DMX 6Fire USB

What is working: Everything except SPDIF
- Hardware Master volume
- PCM 44-192kHz@24 bits, 6 channels out, 4 channels in (analog)
- MIDI in/out
- firmware loading after cold start
- phono/line switching

Signed-off-by: Torsten Schenk <torsten.schenk@zoho.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/6fire/midi.c b/sound/usb/6fire/midi.c
new file mode 100644
index 0000000..13f4509
--- /dev/null
+++ b/sound/usb/6fire/midi.c
@@ -0,0 +1,203 @@
+/*
+ * Linux driver for TerraTec DMX 6Fire USB
+ *
+ * Rawmidi driver
+ *
+ * Author:	Torsten Schenk <torsten.schenk@zoho.com>
+ * Created:	Jan 01, 2011
+ * Version:	0.3.0
+ * Copyright:	(C) Torsten Schenk
+ *
+ * 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.
+ */
+
+#include <sound/rawmidi.h>
+
+#include "midi.h"
+#include "chip.h"
+#include "comm.h"
+
+static void usb6fire_midi_out_handler(struct urb *urb)
+{
+	struct midi_runtime *rt = urb->context;
+	int ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rt->out_lock, flags);
+
+	if (rt->out) {
+		ret = snd_rawmidi_transmit(rt->out, rt->out_buffer + 4,
+				MIDI_BUFSIZE - 4);
+		if (ret > 0) { /* more data available, send next packet */
+			rt->out_buffer[1] = ret + 2;
+			rt->out_buffer[3] = rt->out_serial++;
+			urb->transfer_buffer_length = ret + 4;
+
+			ret = usb_submit_urb(urb, GFP_ATOMIC);
+			if (ret < 0)
+				snd_printk(KERN_ERR PREFIX "midi out urb "
+						"submit failed: %d\n", ret);
+		} else /* no more data to transmit */
+			rt->out = NULL;
+	}
+	spin_unlock_irqrestore(&rt->out_lock, flags);
+}
+
+static void usb6fire_midi_in_received(
+		struct midi_runtime *rt, u8 *data, int length)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&rt->in_lock, flags);
+	if (rt->in)
+		snd_rawmidi_receive(rt->in, data, length);
+	spin_unlock_irqrestore(&rt->in_lock, flags);
+}
+
+static int usb6fire_midi_out_open(struct snd_rawmidi_substream *alsa_sub)
+{
+	return 0;
+}
+
+static int usb6fire_midi_out_close(struct snd_rawmidi_substream *alsa_sub)
+{
+	return 0;
+}
+
+static void usb6fire_midi_out_trigger(
+		struct snd_rawmidi_substream *alsa_sub, int up)
+{
+	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
+	struct urb *urb = &rt->out_urb;
+	__s8 ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rt->out_lock, flags);
+	if (up) { /* start transfer */
+		if (rt->out) { /* we are already transmitting so just return */
+			spin_unlock_irqrestore(&rt->out_lock, flags);
+			return;
+		}
+
+		ret = snd_rawmidi_transmit(alsa_sub, rt->out_buffer + 4,
+				MIDI_BUFSIZE - 4);
+		if (ret > 0) {
+			rt->out_buffer[1] = ret + 2;
+			rt->out_buffer[3] = rt->out_serial++;
+			urb->transfer_buffer_length = ret + 4;
+
+			ret = usb_submit_urb(urb, GFP_ATOMIC);
+			if (ret < 0)
+				snd_printk(KERN_ERR PREFIX "midi out urb "
+						"submit failed: %d\n", ret);
+			else
+				rt->out = alsa_sub;
+		}
+	} else if (rt->out == alsa_sub)
+		rt->out = NULL;
+	spin_unlock_irqrestore(&rt->out_lock, flags);
+}
+
+static void usb6fire_midi_out_drain(struct snd_rawmidi_substream *alsa_sub)
+{
+	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
+	int retry = 0;
+
+	while (rt->out && retry++ < 100)
+		msleep(10);
+}
+
+static int usb6fire_midi_in_open(struct snd_rawmidi_substream *alsa_sub)
+{
+	return 0;
+}
+
+static int usb6fire_midi_in_close(struct snd_rawmidi_substream *alsa_sub)
+{
+	return 0;
+}
+
+static void usb6fire_midi_in_trigger(
+		struct snd_rawmidi_substream *alsa_sub, int up)
+{
+	struct midi_runtime *rt = alsa_sub->rmidi->private_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rt->in_lock, flags);
+	if (up)
+		rt->in = alsa_sub;
+	else
+		rt->in = NULL;
+	spin_unlock_irqrestore(&rt->in_lock, flags);
+}
+
+static struct snd_rawmidi_ops out_ops = {
+	.open = usb6fire_midi_out_open,
+	.close = usb6fire_midi_out_close,
+	.trigger = usb6fire_midi_out_trigger,
+	.drain = usb6fire_midi_out_drain
+};
+
+static struct snd_rawmidi_ops in_ops = {
+	.open = usb6fire_midi_in_open,
+	.close = usb6fire_midi_in_close,
+	.trigger = usb6fire_midi_in_trigger
+};
+
+int __devinit usb6fire_midi_init(struct sfire_chip *chip)
+{
+	int ret;
+	struct midi_runtime *rt = kzalloc(sizeof(struct midi_runtime),
+			GFP_KERNEL);
+	struct comm_runtime *comm_rt = chip->comm;
+
+	if (!rt)
+		return -ENOMEM;
+
+	rt->chip = chip;
+	rt->in_received = usb6fire_midi_in_received;
+	rt->out_buffer[0] = 0x80; /* 'send midi' command */
+	rt->out_buffer[1] = 0x00; /* size of data */
+	rt->out_buffer[2] = 0x00; /* always 0 */
+	spin_lock_init(&rt->in_lock);
+	spin_lock_init(&rt->out_lock);
+
+	comm_rt->init_urb(comm_rt, &rt->out_urb, rt->out_buffer, rt,
+			usb6fire_midi_out_handler);
+
+	ret = snd_rawmidi_new(chip->card, "6FireUSB", 0, 1, 1, &rt->instance);
+	if (ret < 0) {
+		kfree(rt);
+		snd_printk(KERN_ERR PREFIX "unable to create midi.\n");
+		return ret;
+	}
+	rt->instance->private_data = rt;
+	strcpy(rt->instance->name, "DMX6FireUSB MIDI");
+	rt->instance->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
+			SNDRV_RAWMIDI_INFO_INPUT |
+			SNDRV_RAWMIDI_INFO_DUPLEX;
+	snd_rawmidi_set_ops(rt->instance, SNDRV_RAWMIDI_STREAM_OUTPUT,
+			&out_ops);
+	snd_rawmidi_set_ops(rt->instance, SNDRV_RAWMIDI_STREAM_INPUT,
+			&in_ops);
+
+	chip->midi = rt;
+	return 0;
+}
+
+void usb6fire_midi_abort(struct sfire_chip *chip)
+{
+	struct midi_runtime *rt = chip->midi;
+
+	if (rt)
+		usb_poison_urb(&rt->out_urb);
+}
+
+void usb6fire_midi_destroy(struct sfire_chip *chip)
+{
+	kfree(chip->midi);
+	chip->midi = NULL;
+}