[alsa-devel] [PATCH 05/15] ALSA: dice: Add support for MIDI capture/playback

Takashi Sakamoto o-takashi at sakamocchi.jp
Mon Dec 8 16:10:39 CET 2014


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 at sakamocchi.jp>
---
 sound/firewire/dice/Makefile      |   4 +-
 sound/firewire/dice/dice-midi.c   | 157 ++++++++++++++++++++++++++++++++++++++
 sound/firewire/dice/dice-stream.c |   2 +
 sound/firewire/dice/dice.c        |   4 +
 sound/firewire/dice/dice.h        |   3 +
 5 files changed, 168 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..fe43ce7
--- /dev/null
+++ b/sound/firewire/dice/dice-midi.c
@@ -0,0 +1,157 @@
+/*
+ * 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 midi_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)
+		return err;
+
+	mutex_lock(&dice->mutex);
+
+	dice->substreams_counter++;
+	err = snd_dice_stream_start_duplex(dice, 0);
+
+	mutex_unlock(&dice->mutex);
+
+	if (err < 0)
+		snd_dice_stream_lock_release(dice);
+
+	return err;
+}
+
+static int midi_close(struct snd_rawmidi_substream *substream)
+{
+	struct snd_dice *dice = substream->rmidi->private_data;
+
+	mutex_lock(&dice->mutex);
+
+	dice->substreams_counter--;
+	snd_dice_stream_stop_duplex(dice);
+
+	mutex_unlock(&dice->mutex);
+
+	snd_dice_stream_lock_release(dice);
+	return 0;
+}
+
+static void midi_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 midi_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		= midi_open,
+	.close		= midi_close,
+	.trigger	= midi_capture_trigger,
+};
+
+static struct snd_rawmidi_ops playback_ops = {
+	.open		= midi_open,
+	.close		= midi_close,
+	.trigger	= midi_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 20765a0..fa9cf76 100644
--- a/sound/firewire/dice/dice-stream.c
+++ b/sound/firewire/dice/dice-stream.c
@@ -218,6 +218,8 @@ 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 85bcfaf..90d8f40 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 f30326e..ecf5dc8 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
-- 
2.1.0



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