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  	wait_queue_head_t sleep;
67  	/* event handler (new bytes, input only) */
68  	void (*event)(struct snd_rawmidi_substream *substream);
69  	/* defers calls to event [input] or ops->trigger [output] */
70  	struct work_struct event_work;
71  	/* private data */
72  	void *private_data;
73  	void (*private_free)(struct snd_rawmidi_substream *substream);
74  };
75  
76  struct snd_rawmidi_substream {
77  	struct list_head list;		/* list of all substream for given stream */
78  	int stream;			/* direction */
79  	int number;			/* substream number */
80  	bool opened;			/* open flag */
81  	bool append;			/* append flag (merge more streams) */
82  	bool active_sensing;		/* send active sensing when close */
83  	unsigned int framing;		/* whether to frame input data */
84  	unsigned int clock_type;	/* clock source to use for input framing */
85  	int use_count;			/* use counter (for output) */
86  	size_t bytes;
87  	spinlock_t lock;
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_proceed(struct snd_rawmidi_substream *substream);
160  
161  /* main midi functions */
162  
163  int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
164  int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
165  			    int mode, struct snd_rawmidi_file *rfile);
166  int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
167  int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
168  			      struct snd_rawmidi_params *params);
169  int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
170  			     struct snd_rawmidi_params *params);
171  int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream);
172  int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream);
173  int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream);
174  long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
175  			     unsigned char *buf, long count);
176  long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
177  			      const unsigned char *buf, long count);
178  
179  #endif /* __SOUND_RAWMIDI_H */
180