1 /*
2  * u_uac1.h -- interface to USB gadget "ALSA AUDIO" utilities
3  *
4  * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
5  * Copyright (C) 2008 Analog Devices, Inc
6  *
7  * Enter bugs at http://blackfin.uclinux.org/
8  *
9  * Licensed under the GPL-2 or later.
10  */
11 
12 #ifndef __U_AUDIO_H
13 #define __U_AUDIO_H
14 
15 #include <linux/device.h>
16 #include <linux/err.h>
17 #include <linux/usb/audio.h>
18 #include <linux/usb/composite.h>
19 
20 #include <sound/core.h>
21 #include <sound/pcm.h>
22 #include <sound/pcm_params.h>
23 
24 #define FILE_PCM_PLAYBACK	"/dev/snd/pcmC0D0p"
25 #define FILE_PCM_CAPTURE	"/dev/snd/pcmC0D0c"
26 #define FILE_CONTROL		"/dev/snd/controlC0"
27 
28 #define UAC1_OUT_EP_MAX_PACKET_SIZE	200
29 #define UAC1_REQ_COUNT			256
30 #define UAC1_AUDIO_BUF_SIZE		48000
31 
32 /*
33  * This represents the USB side of an audio card device, managed by a USB
34  * function which provides control and stream interfaces.
35  */
36 
37 struct gaudio_snd_dev {
38 	struct gaudio			*card;
39 	struct file			*filp;
40 	struct snd_pcm_substream	*substream;
41 	int				access;
42 	int				format;
43 	int				channels;
44 	int				rate;
45 };
46 
47 struct gaudio {
48 	struct usb_function		func;
49 	struct usb_gadget		*gadget;
50 
51 	/* ALSA sound device interfaces */
52 	struct gaudio_snd_dev		control;
53 	struct gaudio_snd_dev		playback;
54 	struct gaudio_snd_dev		capture;
55 
56 	/* TODO */
57 };
58 
59 struct f_uac1_opts {
60 	struct usb_function_instance	func_inst;
61 	int				req_buf_size;
62 	int				req_count;
63 	int				audio_buf_size;
64 	char				*fn_play;
65 	char				*fn_cap;
66 	char				*fn_cntl;
67 	unsigned			bound:1;
68 	unsigned			fn_play_alloc:1;
69 	unsigned			fn_cap_alloc:1;
70 	unsigned			fn_cntl_alloc:1;
71 	struct mutex			lock;
72 	int				refcnt;
73 };
74 
75 int gaudio_setup(struct gaudio *card);
76 void gaudio_cleanup(struct gaudio *the_card);
77 
78 size_t u_audio_playback(struct gaudio *card, void *buf, size_t count);
79 int u_audio_get_playback_channels(struct gaudio *card);
80 int u_audio_get_playback_rate(struct gaudio *card);
81 
82 #endif /* __U_AUDIO_H */
83