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#include <sound/info.h>
22
23/*
24 * Raw MIDI interface
25 */
26
27#define SNDRV_RAWMIDI_DEVICES 8
28
29#define SNDRV_RAWMIDI_LFLG_OUTPUT (1<<0)
30#define SNDRV_RAWMIDI_LFLG_INPUT (1<<1)
31#define SNDRV_RAWMIDI_LFLG_OPEN (3<<0)
32#define SNDRV_RAWMIDI_LFLG_APPEND (1<<2)
33
34struct snd_rawmidi;
35struct snd_rawmidi_substream;
36struct snd_seq_port_info;
37struct pid;
38
39struct snd_rawmidi_ops {
40 int (*open) (struct snd_rawmidi_substream * substream);
41 int (*close) (struct snd_rawmidi_substream * substream);
42 void (*trigger) (struct snd_rawmidi_substream * substream, int up);
43 void (*drain) (struct snd_rawmidi_substream * substream);
44};
45
46struct snd_rawmidi_global_ops {
47 int (*dev_register) (struct snd_rawmidi * rmidi);
48 int (*dev_unregister) (struct snd_rawmidi * rmidi);
49 void (*get_port_info)(struct snd_rawmidi *rmidi, int number,
50 struct snd_seq_port_info *info);
51 long (*ioctl)(struct snd_rawmidi *rmidi, unsigned int cmd,
52 void __user *argp);
53 void (*proc_read)(struct snd_info_entry *entry,
54 struct snd_info_buffer *buf);
55};
56
57struct snd_rawmidi_runtime {
58 struct snd_rawmidi_substream *substream;
59 unsigned int drain: 1, /* drain stage */
60 oss: 1; /* OSS compatible mode */
61 /* midi stream buffer */
62 unsigned char *buffer; /* buffer for MIDI data */
63 size_t buffer_size; /* size of buffer */
64 size_t appl_ptr; /* application pointer */
65 size_t hw_ptr; /* hardware pointer */
66 size_t avail_min; /* min avail for wakeup */
67 size_t avail; /* max used buffer for wakeup */
68 size_t xruns; /* over/underruns counter */
69 size_t align; /* alignment (0 = byte stream, 3 = UMP) */
70 int buffer_ref; /* buffer reference count */
71 /* misc */
72 wait_queue_head_t sleep;
73 /* event handler (new bytes, input only) */
74 void (*event)(struct snd_rawmidi_substream *substream);
75 /* defers calls to event [input] or ops->trigger [output] */
76 struct work_struct event_work;
77 /* private data */
78 void *private_data;
79 void (*private_free)(struct snd_rawmidi_substream *substream);
80};
81
82struct snd_rawmidi_substream {
83 struct list_head list; /* list of all substream for given stream */
84 int stream; /* direction */
85 int number; /* substream number */
86 bool opened; /* open flag */
87 bool append; /* append flag (merge more streams) */
88 bool active_sensing; /* send active sensing when close */
89 unsigned int framing; /* whether to frame input data */
90 unsigned int clock_type; /* clock source to use for input framing */
91 int use_count; /* use counter (for output) */
92 bool inactive; /* inactive substream (for UMP legacy) */
93 size_t bytes;
94 spinlock_t lock;
95 struct snd_rawmidi *rmidi;
96 struct snd_rawmidi_str *pstr;
97 char name[32];
98 struct snd_rawmidi_runtime *runtime;
99 struct pid *pid;
100 /* hardware layer */
101 const struct snd_rawmidi_ops *ops;
102};
103
104struct snd_rawmidi_file {
105 struct snd_rawmidi *rmidi;
106 struct snd_rawmidi_substream *input;
107 struct snd_rawmidi_substream *output;
108 unsigned int user_pversion; /* supported protocol version */
109};
110
111struct snd_rawmidi_str {
112 unsigned int substream_count;
113 unsigned int substream_opened;
114 struct list_head substreams;
115};
116
117struct snd_rawmidi {
118 struct snd_card *card;
119 struct list_head list;
120 unsigned int device; /* device number */
121 unsigned int info_flags; /* SNDRV_RAWMIDI_INFO_XXXX */
122 unsigned int tied_device;
123 char id[64];
124 char name[80];
125
126#ifdef CONFIG_SND_OSSEMUL
127 int ossreg;
128#endif
129
130 const struct snd_rawmidi_global_ops *ops;
131
132 struct snd_rawmidi_str streams[2];
133
134 void *private_data;
135 void (*private_free) (struct snd_rawmidi *rmidi);
136
137 struct mutex open_mutex;
138 wait_queue_head_t open_wait;
139
140 struct device *dev;
141
142 struct snd_info_entry *proc_entry;
143
144#if IS_ENABLED(CONFIG_SND_SEQUENCER)
145 struct snd_seq_device *seq_dev;
146#endif
147};
148
149/* main rawmidi functions */
150
151int snd_rawmidi_new(struct snd_card *card, char *id, int device,
152 int output_count, int input_count,
153 struct snd_rawmidi **rmidi);
154void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
155 const struct snd_rawmidi_ops *ops);
156
157/* internal */
158int snd_rawmidi_init(struct snd_rawmidi *rmidi,
159 struct snd_card *card, char *id, int device,
160 int output_count, int input_count,
161 unsigned int info_flags);
162int snd_rawmidi_free(struct snd_rawmidi *rmidi);
163
164/* callbacks */
165
166int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
167 const unsigned char *buffer, int count);
168int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream);
169int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
170 unsigned char *buffer, int count);
171int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count);
172int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
173 unsigned char *buffer, int count);
174int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream);
175
176/* main midi functions */
177
178int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
179int snd_rawmidi_kernel_open(struct snd_rawmidi *rmidi, int subdevice,
180 int mode, struct snd_rawmidi_file *rfile);
181int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
182int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
183 struct snd_rawmidi_params *params);
184int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
185 struct snd_rawmidi_params *params);
186int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream);
187int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream);
188int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream);
189long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
190 unsigned char *buf, long count);
191long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
192 const unsigned char *buf, long count);
193
194/* set up the tied devices */
195static inline void snd_rawmidi_tie_devices(struct snd_rawmidi *r1,
196 struct snd_rawmidi *r2)
197{
198 /* tied_device field keeps the device+1 (so that 0 being unknown) */
199 r1->tied_device = r2->device + 1;
200 r2->tied_device = r1->device + 1;
201}
202
203#endif /* __SOUND_RAWMIDI_H */
204

source code of linux/include/sound/rawmidi.h