include/sound/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
  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         spinlock_t lock;
  67         wait_queue_head_t sleep;
  68         /* event handler (new bytes, input only) */
  69         void (*event)(struct snd_rawmidi_substream *substream);
  70         /* defers calls to event [input] or ops->trigger [output] */
  71         struct work_struct event_work;
  72         /* private data */
  73         void *private_data;
  74         void (*private_free)(struct snd_rawmidi_substream *substream);
  75 };
  76
  77 struct snd_rawmidi_substream {
  78         struct list_head list;          /* list of all substream for given stream */
  79         int stream;                     /* direction */
  80         int number;                     /* substream number */
  81         bool opened;                    /* open flag */
  82         bool append;                    /* append flag (merge more streams) */
  83         bool active_sensing;            /* send active sensing when close */
  84         int use_count;                  /* use counter (for output) */
  85         size_t bytes;
  86         struct snd_rawmidi *rmidi;
  87         struct snd_rawmidi_str *pstr;
  88         char name[32];
  89         struct snd_rawmidi_runtime *runtime;
  90         struct pid *pid;
  91         /* hardware layer */
  92         const struct snd_rawmidi_ops *ops;
  93 };
  94
  95 struct snd_rawmidi_file {
  96         struct snd_rawmidi *rmidi;
  97         struct snd_rawmidi_substream *input;
  98         struct snd_rawmidi_substream *output;
  99 };
 100
 101 struct snd_rawmidi_str {
 102         unsigned int substream_count;
 103         unsigned int substream_opened;
 104         struct list_head substreams;
 105 };
 106
 107 struct snd_rawmidi {
 108         struct snd_card *card;
 109         struct list_head list;
 110         unsigned int device;            /* device number */
 111         unsigned int info_flags;        /* SNDRV_RAWMIDI_INFO_XXXX */
 112         char id[64];
 113         char name[80];
 114
 115 #ifdef CONFIG_SND_OSSEMUL
 116         int ossreg;
 117 #endif
 118
 119         const struct snd_rawmidi_global_ops *ops;
 120
 121         struct snd_rawmidi_str streams[2];
 122
 123         void *private_data;
 124         void (*private_free) (struct snd_rawmidi *rmidi);
 125
 126         struct mutex open_mutex;
 127         wait_queue_head_t open_wait;
 128
 129         struct device dev;
 130
 131         struct snd_info_entry *proc_entry;
 132
 133 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
 134         struct snd_seq_device *seq_dev;
 135 #endif
 136 };
 137
 138 /* main rawmidi functions */
 139
 140 int snd_rawmidi_new(struct snd_card *card, char *id, int device,
 141                     int output_count, int input_count,
 142                     struct snd_rawmidi **rmidi);
 143 void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
 144                          const struct snd_rawmidi_ops *ops);
 145
 146 /* callbacks */
 147
 148 int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
 149                         const unsigned char *buffer, int count);
 150 int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream);
 151 int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
 152                               unsigned char *buffer, int count);
 153 int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count);
 154 int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
 155                          unsigned char *buffer, int count);
 156 int __snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
 157                               unsigned char *buffer, int count);
 158 int __snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream,
 159                                int count);
 160 int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream);
 161
 162 /* main midi functions */
 163
 164 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
 165 int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
 166                             int mode, struct snd_rawmidi_file *rfile);
 167 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
 168 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
 169                               struct snd_rawmidi_params *params);
 170 int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
 171                              struct snd_rawmidi_params *params);
 172 int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream);
 173 int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream);
 174 int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream);
 175 long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
 176                              unsigned char *buf, long count);
 177 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
 178                               const unsigned char *buf, long count);
 179
 180 #endif /* __SOUND_RAWMIDI_H */