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 
34 struct snd_rawmidi;
35 struct snd_rawmidi_substream;
36 struct snd_seq_port_info;
37 struct pid;
38 
39 struct 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 
46 struct 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 
57 struct 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 
82 struct 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 	size_t bytes;
93 	spinlock_t lock;
94 	struct snd_rawmidi *rmidi;
95 	struct snd_rawmidi_str *pstr;
96 	char name[32];
97 	struct snd_rawmidi_runtime *runtime;
98 	struct pid *pid;
99 	/* hardware layer */
100 	const struct snd_rawmidi_ops *ops;
101 };
102 
103 struct snd_rawmidi_file {
104 	struct snd_rawmidi *rmidi;
105 	struct snd_rawmidi_substream *input;
106 	struct snd_rawmidi_substream *output;
107 	unsigned int user_pversion;	/* supported protocol version */
108 };
109 
110 struct snd_rawmidi_str {
111 	unsigned int substream_count;
112 	unsigned int substream_opened;
113 	struct list_head substreams;
114 };
115 
116 struct snd_rawmidi {
117 	struct snd_card *card;
118 	struct list_head list;
119 	unsigned int device;		/* device number */
120 	unsigned int info_flags;	/* SNDRV_RAWMIDI_INFO_XXXX */
121 	char id[64];
122 	char name[80];
123 
124 #ifdef CONFIG_SND_OSSEMUL
125 	int ossreg;
126 #endif
127 
128 	const struct snd_rawmidi_global_ops *ops;
129 
130 	struct snd_rawmidi_str streams[2];
131 
132 	void *private_data;
133 	void (*private_free) (struct snd_rawmidi *rmidi);
134 
135 	struct mutex open_mutex;
136 	wait_queue_head_t open_wait;
137 
138 	struct device *dev;
139 
140 	struct snd_info_entry *proc_entry;
141 
142 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
143 	struct snd_seq_device *seq_dev;
144 #endif
145 };
146 
147 /* main rawmidi functions */
148 
149 int snd_rawmidi_new(struct snd_card *card, char *id, int device,
150 		    int output_count, int input_count,
151 		    struct snd_rawmidi **rmidi);
152 void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
153 			 const struct snd_rawmidi_ops *ops);
154 
155 /* internal */
156 int snd_rawmidi_init(struct snd_rawmidi *rmidi,
157 		     struct snd_card *card, char *id, int device,
158 		     int output_count, int input_count,
159 		     unsigned int info_flags);
160 int snd_rawmidi_free(struct snd_rawmidi *rmidi);
161 
162 /* callbacks */
163 
164 int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
165 			const unsigned char *buffer, int count);
166 int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream);
167 int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
168 			      unsigned char *buffer, int count);
169 int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count);
170 int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
171 			 unsigned char *buffer, int count);
172 int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream);
173 
174 /* main midi functions */
175 
176 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
177 int snd_rawmidi_kernel_open(struct snd_rawmidi *rmidi, int subdevice,
178 			    int mode, struct snd_rawmidi_file *rfile);
179 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
180 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
181 			      struct snd_rawmidi_params *params);
182 int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
183 			     struct snd_rawmidi_params *params);
184 int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream);
185 int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream);
186 int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream);
187 long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
188 			     unsigned char *buf, long count);
189 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
190 			      const unsigned char *buf, long count);
191 
192 #endif /* __SOUND_RAWMIDI_H */
193