linux/sound/firewire/fireface/ff-midi.c
Takashi Sakamoto f0f9f497d4 ALSA: fireface: support rx MIDI functionality for Fireface UCX
In latter model of Fireface series, asynchronous transaction includes
a prefix byte to indicate the way to decode included MIDI bytes.

Upper 4 bits of the prefix byte indicates port number, and the rest 4
bits indicate the way to decode rest of bytes for MIDI messages.

Basically the rest bits indicates the number of bytes for MIDI message.
However, if the last byte of each MIDi message is included, the rest
bits are 0xf. For example:

message: f0 00 00 66 14 20 00 00 f7
offset: content (big endian, port 0)
 '0030: 0x02f00000
 '0030: 0x03006614
 '0030: 0x03200000
 '0030: 0x0ff70000

This commit supports encoding scheme for the above and allows
applications to transfer MIDI messages via ALSA rawmidi interface.
An unused member (running_status) is reused to keep state of
transmission of system exclusive messages.

For your information, this is a dump of config rom.

$ sudo ./hinawa-config-rom-printer /dev/fw1
{ 'bus-info': { 'bmc': False,
                'chip_ID': 13225063715,
                'cmc': False,
                'cyc_clk_acc': 0,
                'imc': False,
                'isc': True,
                'max_rec': 512,
                'name': '1394',
                'node_vendor_ID': 2613},
  'root-directory': [ [ 'NODE_CAPABILITIES',
                        { 'addressing': {'64': True, 'fix': True, 'prv': False},
                          'misc': {'int': False, 'ms': False, 'spt': True},
                          'state': { 'atn': False,
                                     'ded': False,
                                     'drq': True,
                                     'elo': False,
                                     'init': False,
                                     'lst': True,
                                     'off': False},
                          'testing': {'bas': False, 'ext': False}}],
                      ['VENDOR', 2613],
                      ['DESCRIPTOR', 'RME!'],
                      ['EUI_64', 2873037108442403],
                      [ 'UNIT',
                        [ ['SPECIFIER_ID', 2613],
                          ['VERSION', 4],
                          ['MODEL', 1054720],
                          ['DESCRIPTOR', 'Fireface UCX']]]]}

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-22 17:20:56 +01:00

130 lines
3.3 KiB
C

/*
* ff-midi.c - a part of driver for RME Fireface series
*
* Copyright (c) 2015-2017 Takashi Sakamoto
*
* Licensed under the terms of the GNU General Public License, version 2.
*/
#include "ff.h"
static int midi_capture_open(struct snd_rawmidi_substream *substream)
{
/* Do nothing. */
return 0;
}
static int midi_playback_open(struct snd_rawmidi_substream *substream)
{
struct snd_ff *ff = substream->rmidi->private_data;
/* Initialize internal status. */
ff->on_sysex[substream->number] = 0;
ff->rx_midi_error[substream->number] = false;
WRITE_ONCE(ff->rx_midi_substreams[substream->number], substream);
return 0;
}
static int midi_capture_close(struct snd_rawmidi_substream *substream)
{
/* Do nothing. */
return 0;
}
static int midi_playback_close(struct snd_rawmidi_substream *substream)
{
struct snd_ff *ff = substream->rmidi->private_data;
cancel_work_sync(&ff->rx_midi_work[substream->number]);
WRITE_ONCE(ff->rx_midi_substreams[substream->number], NULL);
return 0;
}
static void midi_capture_trigger(struct snd_rawmidi_substream *substream,
int up)
{
struct snd_ff *ff = substream->rmidi->private_data;
unsigned long flags;
spin_lock_irqsave(&ff->lock, flags);
if (up)
WRITE_ONCE(ff->tx_midi_substreams[substream->number],
substream);
else
WRITE_ONCE(ff->tx_midi_substreams[substream->number], NULL);
spin_unlock_irqrestore(&ff->lock, flags);
}
static void midi_playback_trigger(struct snd_rawmidi_substream *substream,
int up)
{
struct snd_ff *ff = substream->rmidi->private_data;
unsigned long flags;
spin_lock_irqsave(&ff->lock, flags);
if (up || !ff->rx_midi_error[substream->number])
schedule_work(&ff->rx_midi_work[substream->number]);
spin_unlock_irqrestore(&ff->lock, flags);
}
static void set_midi_substream_names(struct snd_rawmidi_str *stream,
const char *const name)
{
struct snd_rawmidi_substream *substream;
list_for_each_entry(substream, &stream->substreams, list) {
snprintf(substream->name, sizeof(substream->name),
"%s MIDI %d", name, substream->number + 1);
}
}
int snd_ff_create_midi_devices(struct snd_ff *ff)
{
static const struct snd_rawmidi_ops midi_capture_ops = {
.open = midi_capture_open,
.close = midi_capture_close,
.trigger = midi_capture_trigger,
};
static const struct snd_rawmidi_ops midi_playback_ops = {
.open = midi_playback_open,
.close = midi_playback_close,
.trigger = midi_playback_trigger,
};
struct snd_rawmidi *rmidi;
struct snd_rawmidi_str *stream;
int err;
err = snd_rawmidi_new(ff->card, ff->card->driver, 0,
ff->spec->midi_out_ports, ff->spec->midi_in_ports,
&rmidi);
if (err < 0)
return err;
snprintf(rmidi->name, sizeof(rmidi->name),
"%s MIDI", ff->card->shortname);
rmidi->private_data = ff;
rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
&midi_capture_ops);
stream = &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT];
set_midi_substream_names(stream, ff->card->shortname);
rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
&midi_playback_ops);
stream = &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT];
set_midi_substream_names(stream, ff->card->shortname);
rmidi->info_flags |= SNDRV_RAWMIDI_INFO_DUPLEX;
return 0;
}