xref: /linux/include/sound/rawmidi.h (revision 413d6ed3eac387a2876893c337174f0c5b99d01d)
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 	int use_count;			/* use counter (for output) */
85 	size_t bytes;
86 	struct snd_rawmidi *rmidi;
87 	struct snd_rawmidi_str *pstr;
88 	char name[32];
89 	struct snd_rawmidi_runtime *runtime;
90 	struct pid *pid;
91 	/* hardware layer */
92 	const struct snd_rawmidi_ops *ops;
93 };
94 
95 struct snd_rawmidi_file {
96 	struct snd_rawmidi *rmidi;
97 	struct snd_rawmidi_substream *input;
98 	struct snd_rawmidi_substream *output;
99 };
100 
101 struct snd_rawmidi_str {
102 	unsigned int substream_count;
103 	unsigned int substream_opened;
104 	struct list_head substreams;
105 };
106 
107 struct snd_rawmidi {
108 	struct snd_card *card;
109 	struct list_head list;
110 	unsigned int device;		/* device number */
111 	unsigned int info_flags;	/* SNDRV_RAWMIDI_INFO_XXXX */
112 	char id[64];
113 	char name[80];
114 
115 #ifdef CONFIG_SND_OSSEMUL
116 	int ossreg;
117 #endif
118 
119 	const struct snd_rawmidi_global_ops *ops;
120 
121 	struct snd_rawmidi_str streams[2];
122 
123 	void *private_data;
124 	void (*private_free) (struct snd_rawmidi *rmidi);
125 
126 	struct mutex open_mutex;
127 	wait_queue_head_t open_wait;
128 
129 	struct device dev;
130 
131 	struct snd_info_entry *proc_entry;
132 
133 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
134 	struct snd_seq_device *seq_dev;
135 #endif
136 };
137 
138 /* main rawmidi functions */
139 
140 int snd_rawmidi_new(struct snd_card *card, char *id, int device,
141 		    int output_count, int input_count,
142 		    struct snd_rawmidi **rmidi);
143 void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
144 			 const struct snd_rawmidi_ops *ops);
145 
146 /* callbacks */
147 
148 int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
149 			const unsigned char *buffer, int count);
150 int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream);
151 int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
152 			      unsigned char *buffer, int count);
153 int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count);
154 int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
155 			 unsigned char *buffer, int count);
156 int __snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
157 			      unsigned char *buffer, int count);
158 int __snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream,
159 			       int count);
160 int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream);
161 
162 /* main midi functions */
163 
164 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
165 int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
166 			    int mode, struct snd_rawmidi_file *rfile);
167 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
168 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
169 			      struct snd_rawmidi_params *params);
170 int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
171 			     struct snd_rawmidi_params *params);
172 int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream);
173 int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream);
174 int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream);
175 long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
176 			     unsigned char *buf, long count);
177 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
178 			      const unsigned char *buf, long count);
179 
180 #endif /* __SOUND_RAWMIDI_H */
181