xref: /openbmc/linux/sound/usb/line6/playback.h (revision e3b9f1e8)
1 /*
2  * Line 6 Linux USB driver
3  *
4  * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
5  *
6  *	This program is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU General Public License as
8  *	published by the Free Software Foundation, version 2.
9  *
10  */
11 
12 #ifndef PLAYBACK_H
13 #define PLAYBACK_H
14 
15 #include <sound/pcm.h>
16 
17 #include "driver.h"
18 
19 /*
20  * When the TonePort is used with jack in full duplex mode and the outputs are
21  * not connected, the software monitor produces an ugly noise since everything
22  * written to the output buffer (i.e., the input signal) will be repeated in
23  * the next period (sounds like a delay effect). As a workaround, the output
24  * buffer is cleared after the data have been read, but there must be a better
25  * solution. Until one is found, this workaround can be used to fix the
26  * problem.
27  */
28 #define USE_CLEAR_BUFFER_WORKAROUND 1
29 
30 extern const struct snd_pcm_ops snd_line6_playback_ops;
31 
32 extern int line6_create_audio_out_urbs(struct snd_line6_pcm *line6pcm);
33 extern int line6_submit_audio_out_all_urbs(struct snd_line6_pcm *line6pcm);
34 
35 #endif
36