xref: /linux/include/sound/rawmidi.h (revision 1c4b5ecb7ea190fa3e9f9d6891e6c90b60e04f24)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef __SOUND_RAWMIDI_H
3 #define __SOUND_RAWMIDI_H
4 
5 /*
6  *  Abstract layer for MIDI v1.0 stream
7  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
8  */
9 
10 #include <sound/asound.h>
11 #include <linux/interrupt.h>
12 #include <linux/spinlock.h>
13 #include <linux/wait.h>
14 #include <linux/mutex.h>
15 #include <linux/workqueue.h>
16 #include <linux/device.h>
17 
18 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
19 #include <sound/seq_device.h>
20 #endif
21 
22 /*
23  *  Raw MIDI interface
24  */
25 
26 #define SNDRV_RAWMIDI_DEVICES		8
27 
28 #define SNDRV_RAWMIDI_LFLG_OUTPUT	(1<<0)
29 #define SNDRV_RAWMIDI_LFLG_INPUT	(1<<1)
30 #define SNDRV_RAWMIDI_LFLG_OPEN		(3<<0)
31 #define SNDRV_RAWMIDI_LFLG_APPEND	(1<<2)
32 
33 struct snd_rawmidi;
34 struct snd_rawmidi_substream;
35 struct snd_seq_port_info;
36 struct pid;
37 
38 struct snd_rawmidi_ops {
39 	int (*open) (struct snd_rawmidi_substream * substream);
40 	int (*close) (struct snd_rawmidi_substream * substream);
41 	void (*trigger) (struct snd_rawmidi_substream * substream, int up);
42 	void (*drain) (struct snd_rawmidi_substream * substream);
43 };
44 
45 struct snd_rawmidi_global_ops {
46 	int (*dev_register) (struct snd_rawmidi * rmidi);
47 	int (*dev_unregister) (struct snd_rawmidi * rmidi);
48 	void (*get_port_info)(struct snd_rawmidi *rmidi, int number,
49 			      struct snd_seq_port_info *info);
50 };
51 
52 struct snd_rawmidi_runtime {
53 	struct snd_rawmidi_substream *substream;
54 	unsigned int drain: 1,	/* drain stage */
55 		     oss: 1;	/* OSS compatible mode */
56 	/* midi stream buffer */
57 	unsigned char *buffer;	/* buffer for MIDI data */
58 	size_t buffer_size;	/* size of buffer */
59 	size_t appl_ptr;	/* application pointer */
60 	size_t hw_ptr;		/* hardware pointer */
61 	size_t avail_min;	/* min avail for wakeup */
62 	size_t avail;		/* max used buffer for wakeup */
63 	size_t xruns;		/* over/underruns counter */
64 	int buffer_ref;		/* buffer reference count */
65 	/* misc */
66 	spinlock_t lock;
67 	wait_queue_head_t sleep;
68 	/* event handler (new bytes, input only) */
69 	void (*event)(struct snd_rawmidi_substream *substream);
70 	/* defers calls to event [input] or ops->trigger [output] */
71 	struct work_struct event_work;
72 	/* private data */
73 	void *private_data;
74 	void (*private_free)(struct snd_rawmidi_substream *substream);
75 };
76 
77 struct snd_rawmidi_substream {
78 	struct list_head list;		/* list of all substream for given stream */
79 	int stream;			/* direction */
80 	int number;			/* substream number */
81 	bool opened;			/* open flag */
82 	bool append;			/* append flag (merge more streams) */
83 	bool active_sensing;		/* send active sensing when close */
84 	unsigned int framing;		/* whether to frame input data */
85 	unsigned int clock_type;	/* clock source to use for input framing */
86 	int use_count;			/* use counter (for output) */
87 	size_t bytes;
88 	struct snd_rawmidi *rmidi;
89 	struct snd_rawmidi_str *pstr;
90 	char name[32];
91 	struct snd_rawmidi_runtime *runtime;
92 	struct pid *pid;
93 	/* hardware layer */
94 	const struct snd_rawmidi_ops *ops;
95 };
96 
97 struct snd_rawmidi_file {
98 	struct snd_rawmidi *rmidi;
99 	struct snd_rawmidi_substream *input;
100 	struct snd_rawmidi_substream *output;
101 	unsigned int user_pversion;	/* supported protocol version */
102 };
103 
104 struct snd_rawmidi_str {
105 	unsigned int substream_count;
106 	unsigned int substream_opened;
107 	struct list_head substreams;
108 };
109 
110 struct snd_rawmidi {
111 	struct snd_card *card;
112 	struct list_head list;
113 	unsigned int device;		/* device number */
114 	unsigned int info_flags;	/* SNDRV_RAWMIDI_INFO_XXXX */
115 	char id[64];
116 	char name[80];
117 
118 #ifdef CONFIG_SND_OSSEMUL
119 	int ossreg;
120 #endif
121 
122 	const struct snd_rawmidi_global_ops *ops;
123 
124 	struct snd_rawmidi_str streams[2];
125 
126 	void *private_data;
127 	void (*private_free) (struct snd_rawmidi *rmidi);
128 
129 	struct mutex open_mutex;
130 	wait_queue_head_t open_wait;
131 
132 	struct device dev;
133 
134 	struct snd_info_entry *proc_entry;
135 
136 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
137 	struct snd_seq_device *seq_dev;
138 #endif
139 };
140 
141 /* main rawmidi functions */
142 
143 int snd_rawmidi_new(struct snd_card *card, char *id, int device,
144 		    int output_count, int input_count,
145 		    struct snd_rawmidi **rmidi);
146 void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
147 			 const struct snd_rawmidi_ops *ops);
148 
149 /* callbacks */
150 
151 int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
152 			const unsigned char *buffer, int count);
153 int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream);
154 int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
155 			      unsigned char *buffer, int count);
156 int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count);
157 int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
158 			 unsigned char *buffer, int count);
159 int __snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
160 			      unsigned char *buffer, int count);
161 int __snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream,
162 			       int count);
163 int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream);
164 
165 /* main midi functions */
166 
167 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
168 int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
169 			    int mode, struct snd_rawmidi_file *rfile);
170 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
171 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
172 			      struct snd_rawmidi_params *params);
173 int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
174 			     struct snd_rawmidi_params *params);
175 int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream);
176 int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream);
177 int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream);
178 long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
179 			     unsigned char *buf, long count);
180 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
181 			      const unsigned char *buf, long count);
182 
183 #endif /* __SOUND_RAWMIDI_H */
184