blob: 334842daa90459c8f4aeced7a7c0fcbd42ffdf29 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0-or-later */
* Abstract layer for MIDI v1.0 stream
* Copyright (c) by Jaroslav Kysela <>
#include <sound/asound.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>
#include <linux/device.h>
#include <sound/seq_device.h>
* Raw MIDI interface
struct snd_rawmidi;
struct snd_rawmidi_substream;
struct snd_seq_port_info;
struct pid;
struct snd_rawmidi_ops {
int (*open) (struct snd_rawmidi_substream * substream);
int (*close) (struct snd_rawmidi_substream * substream);
void (*trigger) (struct snd_rawmidi_substream * substream, int up);
void (*drain) (struct snd_rawmidi_substream * substream);
struct snd_rawmidi_global_ops {
int (*dev_register) (struct snd_rawmidi * rmidi);
int (*dev_unregister) (struct snd_rawmidi * rmidi);
void (*get_port_info)(struct snd_rawmidi *rmidi, int number,
struct snd_seq_port_info *info);
struct snd_rawmidi_runtime {
struct snd_rawmidi_substream *substream;
unsigned int drain: 1, /* drain stage */
oss: 1; /* OSS compatible mode */
/* midi stream buffer */
unsigned char *buffer; /* buffer for MIDI data */
size_t buffer_size; /* size of buffer */
size_t appl_ptr; /* application pointer */
size_t hw_ptr; /* hardware pointer */
size_t avail_min; /* min avail for wakeup */
size_t avail; /* max used buffer for wakeup */
size_t xruns; /* over/underruns counter */
int buffer_ref; /* buffer reference count */
/* misc */
spinlock_t lock;
wait_queue_head_t sleep;
/* event handler (new bytes, input only) */
void (*event)(struct snd_rawmidi_substream *substream);
/* defers calls to event [input] or ops->trigger [output] */
struct work_struct event_work;
/* private data */
void *private_data;
void (*private_free)(struct snd_rawmidi_substream *substream);
struct snd_rawmidi_substream {
struct list_head list; /* list of all substream for given stream */
int stream; /* direction */
int number; /* substream number */
bool opened; /* open flag */
bool append; /* append flag (merge more streams) */
bool active_sensing; /* send active sensing when close */
int use_count; /* use counter (for output) */
size_t bytes;
struct snd_rawmidi *rmidi;
struct snd_rawmidi_str *pstr;
char name[32];
struct snd_rawmidi_runtime *runtime;
struct pid *pid;
/* hardware layer */
const struct snd_rawmidi_ops *ops;
struct snd_rawmidi_file {
struct snd_rawmidi *rmidi;
struct snd_rawmidi_substream *input;
struct snd_rawmidi_substream *output;
struct snd_rawmidi_str {
unsigned int substream_count;
unsigned int substream_opened;
struct list_head substreams;
struct snd_rawmidi {
struct snd_card *card;
struct list_head list;
unsigned int device; /* device number */
unsigned int info_flags; /* SNDRV_RAWMIDI_INFO_XXXX */
char id[64];
char name[80];
int ossreg;
const struct snd_rawmidi_global_ops *ops;
struct snd_rawmidi_str streams[2];
void *private_data;
void (*private_free) (struct snd_rawmidi *rmidi);
struct mutex open_mutex;
wait_queue_head_t open_wait;
struct device dev;
struct snd_info_entry *proc_entry;
struct snd_seq_device *seq_dev;
/* main rawmidi functions */
int snd_rawmidi_new(struct snd_card *card, char *id, int device,
int output_count, int input_count,
struct snd_rawmidi **rmidi);
void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
const struct snd_rawmidi_ops *ops);
/* callbacks */
int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
const unsigned char *buffer, int count);
int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream);
int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
unsigned char *buffer, int count);
int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count);
int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
unsigned char *buffer, int count);
int __snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
unsigned char *buffer, int count);
int __snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream,
int count);
int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream);
/* main midi functions */
int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
int mode, struct snd_rawmidi_file *rfile);
int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
struct snd_rawmidi_params *params);
int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
struct snd_rawmidi_params *params);
int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream);
int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream);
int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream);
long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
unsigned char *buf, long count);
long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
const unsigned char *buf, long count);
#endif /* __SOUND_RAWMIDI_H */