root/drivers/usb/gadget/function/u_uac1_legacy.h

INCLUDED FROM

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * u_uac1.h -- interface to USB gadget "ALSA AUDIO" utilities
   4  *
   5  * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
   6  * Copyright (C) 2008 Analog Devices, Inc
   7  */
   8 
   9 #ifndef __U_UAC1_LEGACY_H
  10 #define __U_UAC1_LEGACY_H
  11 
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/usb/audio.h>
  15 #include <linux/usb/composite.h>
  16 
  17 #include <sound/core.h>
  18 #include <sound/pcm.h>
  19 #include <sound/pcm_params.h>
  20 
  21 #define FILE_PCM_PLAYBACK       "/dev/snd/pcmC0D0p"
  22 #define FILE_PCM_CAPTURE        "/dev/snd/pcmC0D0c"
  23 #define FILE_CONTROL            "/dev/snd/controlC0"
  24 
  25 #define UAC1_OUT_EP_MAX_PACKET_SIZE     200
  26 #define UAC1_REQ_COUNT                  256
  27 #define UAC1_AUDIO_BUF_SIZE             48000
  28 
  29 /*
  30  * This represents the USB side of an audio card device, managed by a USB
  31  * function which provides control and stream interfaces.
  32  */
  33 
  34 struct gaudio_snd_dev {
  35         struct gaudio                   *card;
  36         struct file                     *filp;
  37         struct snd_pcm_substream        *substream;
  38         int                             access;
  39         int                             format;
  40         int                             channels;
  41         int                             rate;
  42 };
  43 
  44 struct gaudio {
  45         struct usb_function             func;
  46         struct usb_gadget               *gadget;
  47 
  48         /* ALSA sound device interfaces */
  49         struct gaudio_snd_dev           control;
  50         struct gaudio_snd_dev           playback;
  51         struct gaudio_snd_dev           capture;
  52 
  53         /* TODO */
  54 };
  55 
  56 struct f_uac1_legacy_opts {
  57         struct usb_function_instance    func_inst;
  58         int                             req_buf_size;
  59         int                             req_count;
  60         int                             audio_buf_size;
  61         char                            *fn_play;
  62         char                            *fn_cap;
  63         char                            *fn_cntl;
  64         unsigned                        bound:1;
  65         unsigned                        fn_play_alloc:1;
  66         unsigned                        fn_cap_alloc:1;
  67         unsigned                        fn_cntl_alloc:1;
  68         struct mutex                    lock;
  69         int                             refcnt;
  70 };
  71 
  72 int gaudio_setup(struct gaudio *card);
  73 void gaudio_cleanup(struct gaudio *the_card);
  74 
  75 size_t u_audio_playback(struct gaudio *card, void *buf, size_t count);
  76 int u_audio_get_playback_channels(struct gaudio *card);
  77 int u_audio_get_playback_rate(struct gaudio *card);
  78 
  79 #endif /* __U_UAC1_LEGACY_H */