ALSA: firewire-lib: schedule work again when MIDI substream has rest …

…of MIDI messages Currently, when two MIDI trigger callbacks can be called immediately, transactions for the second MIDI messages can be postpone till next trigger callback. This is not good for real-time message transmission. This commit schedules work again at response handling callback if the MIDI substream still includes untransferred MIDI messages. Signed-off-by: Takashi Sakamoto <[email protected]> Signed-off-by: Takashi Iwai <[email protected]>
olifre · Oct 9, 2015 · e8a40d9 · e8a40d9
1 parent d3ef9cb
commit e8a40d9
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/sound/firewire/lib.c b/sound/firewire/lib.c
@@ -78,6 +78,9 @@ static void async_midi_port_callback(struct fw_card *card, int rcode,
 		snd_rawmidi_transmit_ack(substream, port->consume_bytes);
 
 	port->idling = true;
+
+	if (!snd_rawmidi_transmit_empty(substream))
+		schedule_work(&port->work);
 }
 
 static void midi_port_work(struct work_struct *work)