text: #ifndef __SOUND_RAWMIDI_H
  #define __SOUND_RAWMIDI_H
  
  /*
   *  Abstract layer for MIDI v1.0 stream
   *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
   *
   *
   *   This program is free software; you can redistribute it and/or modify
   *   it under the terms of the GNU General Public License as published by
   *   the Free Software Foundation; either version 2 of the License, or
   *   (at your option) any later version.
   *
   *   This program is distributed in the hope that it will be useful,
   *   but WITHOUT ANY WARRANTY; without even the implied warranty of
   *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *   GNU General Public License for more details.
   *
   *   You should have received a copy of the GNU General Public License
   *   along with this program; if not, write to the Free Software
   *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   *
   */
  
  #include <sound/asound.h>
  #include <linux/interrupt.h>
  #include <linux/spinlock.h>
  #include <linux/wait.h>
  #include <asm/semaphore.h>
  
  #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
  #include "seq_device.h"
  #endif
  
  /*
   *  Raw MIDI interface
   */
  
  #define SNDRV_RAWMIDI_DEVICES		8
  
  #define SNDRV_RAWMIDI_LFLG_OUTPUT	(1<<0)
  #define SNDRV_RAWMIDI_LFLG_INPUT	(1<<1)
  #define SNDRV_RAWMIDI_LFLG_OPEN		(3<<0)
  #define SNDRV_RAWMIDI_LFLG_APPEND	(1<<2)
  #define	SNDRV_RAWMIDI_LFLG_NOOPENLOCK	(1<<3)
  
  struct snd_rawmidi;
  struct snd_rawmidi_substream;
  
  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);
  };
  
  struct snd_rawmidi_runtime {
  	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 */
  	/* 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 tasklet_struct tasklet;
  	/* 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 */
  	unsigned int opened: 1,		/* open flag */
  		     append: 1,		/* append flag (merge more streams) */
  		     active_sensing: 1; /* 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;
  	/* hardware layer */
  	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];
  
  #ifdef CONFIG_SND_OSSEMUL
  	int ossreg;
  #endif
  
  	struct snd_rawmidi_global_ops *ops;
  
  	struct snd_rawmidi_str streams[2];
  
  	void *private_data;
  	void (*private_free) (struct snd_rawmidi *rmidi);
  
  	struct semaphore open_mutex;
  	wait_queue_head_t open_wait;
  
  	struct snd_info_entry *dev;
  	struct snd_info_entry *proc_entry;
  
  #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE)
  	struct snd_seq_device *seq_dev;
  #endif
  };
  
  /* 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,
  			 struct snd_rawmidi_ops *ops);
  
  /* callbacks */
  
  void snd_rawmidi_receive_reset(struct snd_rawmidi_substream *substream);
  int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
  			const unsigned char *buffer, int count);
  void snd_rawmidi_transmit_reset(struct snd_rawmidi_substream *substream);
  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);
  
  /* 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 */
  