From 9fbfd38b204a3f04272183c0258a3ded03a5aae8 Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Sun, 11 Oct 2015 12:30:16 +0900 Subject: ALSA: firewire-digi00x: add support for MIDI ports corresponding to isochronous packet streaming This commit adds MIDI functionality to capture/playback MIDI messages from/to physical MIDI ports. These messages are transferred in isochronous packets. When no substreams request AMDTP streams to run, this driver starts the streams at current sampling rate. When other substreams start at different sampling rate, the streams are stopped temporarily, then start again at requested sampling rate. This operation can generate missing MIDI bytes, thus it's preferable to start PCM substreams at favorite sampling rate in advance. Digi 002/003 console also has a set of MIDI port for physical controls. These ports are added in later commits. Signed-off-by: Takashi Sakamoto Signed-off-by: Takashi Iwai --- sound/firewire/digi00x/digi00x-stream.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'sound/firewire/digi00x/digi00x-stream.c') diff --git a/sound/firewire/digi00x/digi00x-stream.c b/sound/firewire/digi00x/digi00x-stream.c index e9be162fc895..4d3b4ebbdd49 100644 --- a/sound/firewire/digi00x/digi00x-stream.c +++ b/sound/firewire/digi00x/digi00x-stream.c @@ -285,6 +285,8 @@ int snd_dg00x_stream_start_duplex(struct snd_dg00x *dg00x, unsigned int rate) err = snd_dg00x_stream_get_local_rate(dg00x, &curr_rate); if (err < 0) goto error; + if (rate == 0) + rate = curr_rate; if (curr_rate != rate || amdtp_streaming_error(&dg00x->tx_stream) || amdtp_streaming_error(&dg00x->rx_stream)) { -- cgit v1.2.3-59-g8ed1b