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  * Enter bugs at http://blackfin.uclinux.org/
9  */
10 
11 #ifndef __U_UAC1_LEGACY_H
12 #define __U_UAC1_LEGACY_H
13 
14 #include <linux/device.h>
15 #include <linux/err.h>
16 #include <linux/usb/audio.h>
17 #include <linux/usb/composite.h>
18 
19 #include <sound/core.h>
20 #include <sound/pcm.h>
21 #include <sound/pcm_params.h>
22 
23 #define FILE_PCM_PLAYBACK	"/dev/snd/pcmC0D0p"
24 #define FILE_PCM_CAPTURE	"/dev/snd/pcmC0D0c"
25 #define FILE_CONTROL		"/dev/snd/controlC0"
26 
27 #define UAC1_OUT_EP_MAX_PACKET_SIZE	200
28 #define UAC1_REQ_COUNT			256
29 #define UAC1_AUDIO_BUF_SIZE		48000
30 
31 /*
32  * This represents the USB side of an audio card device, managed by a USB
33  * function which provides control and stream interfaces.
34  */
35 
36 struct gaudio_snd_dev {
37 	struct gaudio			*card;
38 	struct file			*filp;
39 	struct snd_pcm_substream	*substream;
40 	int				access;
41 	int				format;
42 	int				channels;
43 	int				rate;
44 };
45 
46 struct gaudio {
47 	struct usb_function		func;
48 	struct usb_gadget		*gadget;
49 
50 	/* ALSA sound device interfaces */
51 	struct gaudio_snd_dev		control;
52 	struct gaudio_snd_dev		playback;
53 	struct gaudio_snd_dev		capture;
54 
55 	/* TODO */
56 };
57 
58 struct f_uac1_legacy_opts {
59 	struct usb_function_instance	func_inst;
60 	int				req_buf_size;
61 	int				req_count;
62 	int				audio_buf_size;
63 	char				*fn_play;
64 	char				*fn_cap;
65 	char				*fn_cntl;
66 	unsigned			bound:1;
67 	unsigned			fn_play_alloc:1;
68 	unsigned			fn_cap_alloc:1;
69 	unsigned			fn_cntl_alloc:1;
70 	struct mutex			lock;
71 	int				refcnt;
72 };
73 
74 int gaudio_setup(struct gaudio *card);
75 void gaudio_cleanup(struct gaudio *the_card);
76 
77 size_t u_audio_playback(struct gaudio *card, void *buf, size_t count);
78 int u_audio_get_playback_channels(struct gaudio *card);
79 int u_audio_get_playback_rate(struct gaudio *card);
80 
81 #endif /* __U_UAC1_LEGACY_H */
82