sound/firewire/motu/motu-midi.c

Source file repositories/reference/linux-study-clean/sound/firewire/motu/motu-midi.c

File Facts

System
Linux kernel
Corpus path
sound/firewire/motu/motu-midi.c
Extension
.c
Size
3104 bytes
Lines
127
Domain
Driver Families
Bucket
sound/firewire
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (err >= 0) {
			++motu->substreams_counter;
			err = snd_motu_stream_start_duplex(motu);
			if (err < 0)
				--motu->substreams_counter;
		}
	}

	if (err < 0)
		snd_motu_stream_lock_release(motu);

	return err;
}

static int midi_close(struct snd_rawmidi_substream *substream)
{
	struct snd_motu *motu = substream->rmidi->private_data;

	scoped_guard(mutex, &motu->mutex) {
		--motu->substreams_counter;
		snd_motu_stream_stop_duplex(motu);
	}

	snd_motu_stream_lock_release(motu);
	return 0;
}

static void midi_capture_trigger(struct snd_rawmidi_substream *substrm, int up)
{
	struct snd_motu *motu = substrm->rmidi->private_data;

	guard(spinlock_irqsave)(&motu->lock);

	if (up)
		amdtp_motu_midi_trigger(&motu->tx_stream, substrm->number,
					substrm);
	else
		amdtp_motu_midi_trigger(&motu->tx_stream, substrm->number,
					NULL);
}

static void midi_playback_trigger(struct snd_rawmidi_substream *substrm, int up)
{
	struct snd_motu *motu = substrm->rmidi->private_data;

	guard(spinlock_irqsave)(&motu->lock);

	if (up)
		amdtp_motu_midi_trigger(&motu->rx_stream, substrm->number,
					substrm);
	else
		amdtp_motu_midi_trigger(&motu->rx_stream, substrm->number,
					NULL);
}

static void set_midi_substream_names(struct snd_motu *motu,
				     struct snd_rawmidi_str *str)
{
	struct snd_rawmidi_substream *subs;

	list_for_each_entry(subs, &str->substreams, list) {
		scnprintf(subs->name, sizeof(subs->name),
			  "%s MIDI %d", motu->card->shortname, subs->number + 1);
	}
}

int snd_motu_create_midi_devices(struct snd_motu *motu)
{
	static const struct snd_rawmidi_ops capture_ops = {
		.open		= midi_open,
		.close		= midi_close,
		.trigger	= midi_capture_trigger,
	};
	static const struct snd_rawmidi_ops playback_ops = {
		.open		= midi_open,
		.close		= midi_close,
		.trigger	= midi_playback_trigger,
	};
	struct snd_rawmidi *rmidi;
	struct snd_rawmidi_str *str;
	int err;

	/* create midi ports */
	err = snd_rawmidi_new(motu->card, motu->card->driver, 0, 1, 1, &rmidi);
	if (err < 0)
		return err;

	snprintf(rmidi->name, sizeof(rmidi->name),
		 "%s MIDI", motu->card->shortname);
	rmidi->private_data = motu;

Annotation

Implementation Notes