1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * bebob_yamaha.c - a part of driver for BeBoB based devices
4 *
5 * Copyright (c) 2013-2014 Takashi Sakamoto
6 */
7
8 #include "./bebob.h"
9
10 /*
11 * NOTE:
12 * Yamaha GO44 is not designed to be used as stand-alone mixer. So any streams
13 * must be accompanied. If changing the state, a LED on the device starts to
14 * blink and its sync status is false. In this state, the device sounds nothing
15 * even if streaming. To start streaming at the current sampling rate is only
16 * way to recover this state. GO46 is better for stand-alone mixer.
17 *
18 * Both of them have a capability to change its sampling rate up to 192.0kHz.
19 * At 192.0kHz, the device reports 4 PCM-in, 1 MIDI-in, 6 PCM-out, 1 MIDI-out.
20 * But Yamaha's driver reduce 2 PCM-in, 1 MIDI-in, 2 PCM-out, 1 MIDI-out to use
21 * 'Extended Stream Format Information Command - Single Request' in 'Additional
22 * AVC commands' defined by BridgeCo.
23 * This ALSA driver don't do this because a bit tiresome. Then isochronous
24 * streaming with many asynchronous transactions brings sounds with noises.
25 * Unfortunately current 'ffado-mixer' generated many asynchronous transaction
26 * to observe device's state, mainly check cmp connection and signal format. I
27 * recommend users to close ffado-mixer at 192.0kHz if mixer is needless.
28 *
29 * Terratec PHASE 24 FW and PHASE X24 FW are internally the same as
30 * Yamaha GO 44 and GO 46. Yamaha and Terratec had cooperated for these models.
31 */
32
33 static const enum snd_bebob_clock_type clk_src_types[] = {
34 SND_BEBOB_CLOCK_TYPE_INTERNAL,
35 SND_BEBOB_CLOCK_TYPE_EXTERNAL, /* S/PDIF */
36 };
37 static int
38 clk_src_get(struct snd_bebob *bebob, unsigned int *id)
39 {
40 int err;
41
42 err = avc_audio_get_selector(bebob->unit, 0, 4, id);
43 if (err < 0)
44 return err;
45
46 if (*id >= ARRAY_SIZE(clk_src_types))
47 return -EIO;
48
49 return 0;
50 }
51 static const struct snd_bebob_clock_spec clock_spec = {
52 .num = ARRAY_SIZE(clk_src_types),
53 .types = clk_src_types,
54 .get = &clk_src_get,
55 };
56 static const struct snd_bebob_rate_spec rate_spec = {
57 .get = &snd_bebob_stream_get_rate,
58 .set = &snd_bebob_stream_set_rate,
59 };
60 const struct snd_bebob_spec yamaha_terratec_spec = {
61 .clock = &clock_spec,
62 .rate = &rate_spec,
63 .meter = NULL
64 };