[PATCH 13/29] ALSA: dice: Add support for MIDI capture/playback

[Takashi Sakamoto <o-takashi@sakamocchi.jp>]

This commit adds a support for MIDI capture/playback

When MIDI substrams already start streaming and PCM substreams are going to
join at different sampling rate, streams are stopped once. Then sampling rate
is changed and streams are restarted.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 sound/firewire/dice/Makefile      |   4 +-
 sound/firewire/dice/dice-midi.c   | 176 ++++++++++++++++++++++++++++++++++++++
 sound/firewire/dice/dice-stream.c |   2 +
 sound/firewire/dice/dice.c        |   4 +
 sound/firewire/dice/dice.h        |   3 +
 5 files changed, 187 insertions(+), 2 deletions(-)
 create mode 100644 sound/firewire/dice/dice-midi.c

diff --git a/sound/firewire/dice/Makefile b/sound/firewire/dice/Makefile
index 9a48289..9ef228e 100644
--- a/sound/firewire/dice/Makefile
+++ b/sound/firewire/dice/Makefile
@@ -1,3 +1,3 @@
-snd-dice-objs := dice-transaction.o dice-stream.o dice-proc.o dice-pcm.o \
-		 dice-hwdep.o dice.o
+snd-dice-objs := dice-transaction.o dice-stream.o dice-proc.o dice-midi.o \
+		 dice-pcm.o dice-hwdep.o dice.o
 obj-m += snd-dice.o
diff --git a/sound/firewire/dice/dice-midi.c b/sound/firewire/dice/dice-midi.c
new file mode 100644
index 0000000..4f4eae7
--- /dev/null
+++ b/sound/firewire/dice/dice-midi.c
@@ -0,0 +1,176 @@
+/*
+ * dice_midi.c - a part of driver for Dice based devices
+ *
+ * Copyright (c) 2014 Takashi Sakamoto
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+#include "dice.h"
+
+static int capture_open(struct snd_rawmidi_substream *substream)
+{
+	struct snd_dice *dice = substream->rmidi->private_data;
+	int err;
+
+	err = snd_dice_stream_lock_try(dice);
+	if (err < 0)
+		goto end;
+
+	atomic_inc(&dice->substreams_counter);
+	err = snd_dice_stream_start_duplex(dice, 0);
+	if (err < 0)
+		snd_dice_stream_lock_release(dice);
+end:
+	return err;
+}
+
+static int playback_open(struct snd_rawmidi_substream *substream)
+{
+	struct snd_dice *dice = substream->rmidi->private_data;
+	int err;
+
+	err = snd_dice_stream_lock_try(dice);
+	if (err < 0)
+		goto end;
+
+	atomic_inc(&dice->substreams_counter);
+	err = snd_dice_stream_start_duplex(dice, 0);
+	if (err < 0)
+		snd_dice_stream_lock_release(dice);
+end:
+	return err;
+}
+
+static int capture_close(struct snd_rawmidi_substream *substream)
+{
+	struct snd_dice *dice = substream->rmidi->private_data;
+
+	atomic_dec(&dice->substreams_counter);
+	snd_dice_stream_stop_duplex(dice);
+
+	snd_dice_stream_lock_release(dice);
+	return 0;
+}
+
+static int playback_close(struct snd_rawmidi_substream *substream)
+{
+	struct snd_dice *dice = substream->rmidi->private_data;
+
+	atomic_dec(&dice->substreams_counter);
+	snd_dice_stream_stop_duplex(dice);
+
+	snd_dice_stream_lock_release(dice);
+	return 0;
+}
+
+static void capture_trigger(struct snd_rawmidi_substream *substrm, int up)
+{
+	struct snd_dice *dice = substrm->rmidi->private_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dice->lock, flags);
+
+	if (up)
+		amdtp_stream_midi_trigger(&dice->tx_stream,
+					  substrm->number, substrm);
+	else
+		amdtp_stream_midi_trigger(&dice->tx_stream,
+					  substrm->number, NULL);
+
+	spin_unlock_irqrestore(&dice->lock, flags);
+}
+
+static void playback_trigger(struct snd_rawmidi_substream *substrm, int up)
+{
+	struct snd_dice *dice = substrm->rmidi->private_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dice->lock, flags);
+
+	if (up)
+		amdtp_stream_midi_trigger(&dice->rx_stream,
+					  substrm->number, substrm);
+	else
+		amdtp_stream_midi_trigger(&dice->rx_stream,
+					  substrm->number, NULL);
+
+	spin_unlock_irqrestore(&dice->lock, flags);
+}
+
+static struct snd_rawmidi_ops capture_ops = {
+	.open		= capture_open,
+	.close		= capture_close,
+	.trigger	= capture_trigger,
+};
+
+static struct snd_rawmidi_ops playback_ops = {
+	.open		= playback_open,
+	.close		= playback_close,
+	.trigger	= playback_trigger,
+};
+
+static void set_midi_substream_names(struct snd_dice *dice,
+				     struct snd_rawmidi_str *str)
+{
+	struct snd_rawmidi_substream *subs;
+
+	list_for_each_entry(subs, &str->substreams, list) {
+		snprintf(subs->name, sizeof(subs->name),
+			 "%s MIDI %d", dice->card->shortname, subs->number + 1);
+	}
+}
+
+int snd_dice_create_midi(struct snd_dice *dice)
+{
+	struct snd_rawmidi *rmidi;
+	struct snd_rawmidi_str *str;
+	unsigned int i, midi_in_ports, midi_out_ports;
+	int err;
+
+	midi_in_ports = midi_out_ports = 0;
+	for (i = 0; i < 3; i++) {
+		midi_in_ports = max(dice->tx_midi_ports[i], midi_in_ports);
+		midi_out_ports = max(dice->rx_midi_ports[i], midi_out_ports);
+	}
+
+	if (midi_in_ports + midi_out_ports == 0)
+		return 0;
+
+	/* create midi ports */
+	err = snd_rawmidi_new(dice->card, dice->card->driver, 0,
+			      midi_out_ports, midi_in_ports,
+			      &rmidi);
+	if (err < 0)
+		return err;
+
+	snprintf(rmidi->name, sizeof(rmidi->name),
+		 "%s MIDI", dice->card->shortname);
+	rmidi->private_data = dice;
+
+	if (midi_in_ports > 0) {
+		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
+
+		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
+				    &capture_ops);
+
+		str = &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT];
+
+		set_midi_substream_names(dice, str);
+	}
+
+	if (midi_out_ports > 0) {
+		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
+
+		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
+				    &playback_ops);
+
+		str = &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT];
+
+		set_midi_substream_names(dice, str);
+	}
+
+	if ((midi_out_ports > 0) && (midi_in_ports > 0))
+		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_DUPLEX;
+
+	return 0;
+}
diff --git a/sound/firewire/dice/dice-stream.c b/sound/firewire/dice/dice-stream.c
index bc3715b..37d1aab 100644
--- a/sound/firewire/dice/dice-stream.c
+++ b/sound/firewire/dice/dice-stream.c
@@ -220,6 +220,8 @@ int snd_dice_stream_start_duplex(struct snd_dice *dice, unsigned int rate)
 			"fail to get sampling rate\n");
 		goto end;
 	}
+	if (rate == 0)
+		rate = curr_rate;
 	if (rate != curr_rate)
 		stop_stream(dice, master);
 
diff --git a/sound/firewire/dice/dice.c b/sound/firewire/dice/dice.c
index 2390cc6..b6b2c92 100644
--- a/sound/firewire/dice/dice.c
+++ b/sound/firewire/dice/dice.c
@@ -279,6 +279,10 @@ static int dice_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
 
 	snd_dice_create_proc(dice);
 
+	err = snd_dice_create_midi(dice);
+	if (err < 0)
+		goto error;
+
 	err = snd_dice_stream_init_duplex(dice);
 	if (err < 0)
 		goto error;
diff --git a/sound/firewire/dice/dice.h b/sound/firewire/dice/dice.h
index 8ea5cb4..dbfb988 100644
--- a/sound/firewire/dice/dice.h
+++ b/sound/firewire/dice/dice.h
@@ -32,6 +32,7 @@
 #include <sound/initval.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
+#include <sound/rawmidi.h>
 
 #include "../amdtp.h"
 #include "../iso-resources.h"
@@ -183,4 +184,6 @@ int snd_dice_create_hwdep(struct snd_dice *dice);
 
 void snd_dice_create_proc(struct snd_dice *dice);
 
+int snd_dice_create_midi(struct snd_dice *dice);
+
 #endif
-- 
1.9.1