1 files changed, 64 insertions, 0 deletions
diff --git a/sound/firewire/bebob/bebob_yamaha_terratec.c b/sound/firewire/bebob/bebob_yamaha_terratec.c
new file mode 100644
index 000000000..ce1975e6a
--- /dev/null
+++ b/sound/firewire/bebob/bebob_yamaha_terratec.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * bebob_yamaha.c - a part of driver for BeBoB based devices
+ *
+ * Copyright (c) 2013-2014 Takashi Sakamoto
+ */
+
+#include "./bebob.h"
+
+/*
+ * NOTE:
+ * Yamaha GO44 is not designed to be used as stand-alone mixer. So any streams
+ * must be accompanied. If changing the state, a LED on the device starts to
+ * blink and its sync status is false. In this state, the device sounds nothing
+ * even if streaming. To start streaming at the current sampling rate is only
+ * way to recover this state. GO46 is better for stand-alone mixer.
+ *
+ * Both of them have a capability to change its sampling rate up to 192.0kHz.
+ * At 192.0kHz, the device reports 4 PCM-in, 1 MIDI-in, 6 PCM-out, 1 MIDI-out.
+ * But Yamaha's driver reduce 2 PCM-in, 1 MIDI-in, 2 PCM-out, 1 MIDI-out to use
+ * 'Extended Stream Format Information Command - Single Request' in 'Additional
+ * AVC commands' defined by BridgeCo.
+ * This ALSA driver don't do this because a bit tiresome. Then isochronous
+ * streaming with many asynchronous transactions brings sounds with noises.
+ * Unfortunately current 'ffado-mixer' generated many asynchronous transaction
+ * to observe device's state, mainly check cmp connection and signal format. I
+ * recommend users to close ffado-mixer at 192.0kHz if mixer is needless.
+ *
+ * Terratec PHASE 24 FW and PHASE X24 FW are internally the same as
+ * Yamaha GO 44 and GO 46. Yamaha and Terratec had cooperated for these models.
+ */
+
+static const enum snd_bebob_clock_type clk_src_types[] = {
+	SND_BEBOB_CLOCK_TYPE_INTERNAL,
+	SND_BEBOB_CLOCK_TYPE_EXTERNAL,	/* S/PDIF */
+};
+static int
+clk_src_get(struct snd_bebob *bebob, unsigned int *id)
+{
+	int err;
+
+	err = avc_audio_get_selector(bebob->unit, 0, 4, id);
+	if (err < 0)
+		return err;
+
+	if (*id >= ARRAY_SIZE(clk_src_types))
+		return -EIO;
+
+	return 0;
+}
+static const struct snd_bebob_clock_spec clock_spec = {
+	.num	= ARRAY_SIZE(clk_src_types),
+	.types	= clk_src_types,
+	.get	= &clk_src_get,
+};
+static const struct snd_bebob_rate_spec rate_spec = {
+	.get	= &snd_bebob_stream_get_rate,
+	.set	= &snd_bebob_stream_set_rate,
+};
+const struct snd_bebob_spec yamaha_terratec_spec = {
+	.clock	= &clock_spec,
+	.rate	= &rate_spec,
+	.meter	= NULL
+};