sound/usb/line6/playback.h

   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