rawmidi.h

  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 */