/* * bebob_yamaha.c - a part of driver for BeBoB based devices * * Copyright (c) 2013-2014 Takashi Sakamoto * * Licensed under the terms of the GNU General Public License, version 2. */ #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 };