android_kernel_xiaomi_sm8350/drivers/usb/gadget/u_audio.h
Bryan Wu c6994e6f06 USB: gadget: add USB Audio Gadget driver
Funtions added:
 - setup all the USB audio class device descriptors
 - handle class specific setup request
 - receive data from USB host by ISO transfer
 - play audio data by ALSA sound card
 - open and setup playback PCM interface
 - set default playback PCM parameters
 - provide playback functions for USB audio driver
 - provide PCM parameters set/get functions

Test on:
 - Host: Ubuntu 8.10, kernel 2.6.27
 - Gadget: EZKIT-BF548 with ASoC AD1980 codec

Todo:
 - add real Mute control code
 - add real Volume control code
 - maybe find another way to replace dynamic buffer handling
   with static buffer allocation
 - test on Windows system
 - provide control interface to handle mute/volume control
 - provide capture interface in the future
 - test on BF527, other USB device controler and other audio codec

Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:44:47 -07:00

57 lines
1.1 KiB
C

/*
* u_audio.h -- interface to USB gadget "ALSA AUDIO" utilities
*
* Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
* Copyright (C) 2008 Analog Devices, Inc
*
* Enter bugs at http://blackfin.uclinux.org/
*
* Licensed under the GPL-2 or later.
*/
#ifndef __U_AUDIO_H
#define __U_AUDIO_H
#include <linux/device.h>
#include <linux/err.h>
#include <linux/usb/audio.h>
#include <linux/usb/composite.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include "gadget_chips.h"
/*
* This represents the USB side of an audio card device, managed by a USB
* function which provides control and stream interfaces.
*/
struct gaudio_snd_dev {
struct gaudio *card;
struct file *filp;
struct snd_pcm_substream *substream;
int access;
int format;
int channels;
int rate;
};
struct gaudio {
struct usb_function func;
struct usb_gadget *gadget;
/* ALSA sound device interfaces */
struct gaudio_snd_dev control;
struct gaudio_snd_dev playback;
struct gaudio_snd_dev capture;
/* TODO */
};
int gaudio_setup(struct gaudio *card);
void gaudio_cleanup(struct gaudio *card);
#endif /* __U_AUDIO_H */