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 #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         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
 104 struct 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
 111 struct snd_rawmidi_str {
 112         unsigned int substream_count;
 113         unsigned int substream_opened;
 114         struct list_head substreams;
 115 };
 116
 117 struct 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
 151 int snd_rawmidi_new(struct snd_card *card, char *id, int device,
 152                     int output_count, int input_count,
 153                     struct snd_rawmidi **rmidi);
 154 void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
 155                          const struct snd_rawmidi_ops *ops);
 156
 157 /* internal */
 158 int 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);
 162 int snd_rawmidi_free(struct snd_rawmidi *rmidi);
 163
 164 /* callbacks */
 165
 166 int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
 167                         const unsigned char *buffer, int count);
 168 int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream);
 169 int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
 170                               unsigned char *buffer, int count);
 171 int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count);
 172 int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
 173                          unsigned char *buffer, int count);
 174 int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream);
 175
 176 /* main midi functions */
 177
 178 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
 179 int snd_rawmidi_kernel_open(struct snd_rawmidi *rmidi, int subdevice,
 180                             int mode, struct snd_rawmidi_file *rfile);
 181 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
 182 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
 183                               struct snd_rawmidi_params *params);
 184 int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
 185                              struct snd_rawmidi_params *params);
 186 int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream);
 187 int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream);
 188 int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream);
 189 long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
 190                              unsigned char *buf, long count);
 191 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
 192                               const unsigned char *buf, long count);
 193
 194 /* set up the tied devices */
 195 static 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 */