xref: /openbmc/linux/sound/usb/line6/playback.h (revision 3cf3cdea)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Line 6 Linux USB driver
4  *
5  * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
6  */
7 
8 #ifndef PLAYBACK_H
9 #define PLAYBACK_H
10 
11 #include <sound/pcm.h>
12 
13 #include "driver.h"
14 
15 /*
16  * When the TonePort is used with jack in full duplex mode and the outputs are
17  * not connected, the software monitor produces an ugly noise since everything
18  * written to the output buffer (i.e., the input signal) will be repeated in
19  * the next period (sounds like a delay effect). As a workaround, the output
20  * buffer is cleared after the data have been read, but there must be a better
21  * solution. Until one is found, this workaround can be used to fix the
22  * problem.
23  */
24 #define USE_CLEAR_BUFFER_WORKAROUND 1
25 
26 extern const struct snd_pcm_ops snd_line6_playback_ops;
27 
28 extern int line6_create_audio_out_urbs(struct snd_line6_pcm *line6pcm);
29 extern int line6_submit_audio_out_all_urbs(struct snd_line6_pcm *line6pcm);
30 
31 #endif
32