#ifndef __SOUND_I2C_H
  #define __SOUND_I2C_H
  
  /*
   *
   *
   *   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
   *
   *
   */

  #define SND_I2C_DEVICE_ADDRTEN	(1<<0)	/* 10-bit I2C address */

  struct snd_i2c_device {

  	struct list_head list;

  	struct snd_i2c_bus *bus;	/* I2C bus */

  	char name[32];		/* some useful device name */
  	unsigned short flags;	/* device flags */
  	unsigned short addr;	/* device address (might be 10-bit) */
  	unsigned long private_value;
  	void *private_data;

  	void (*private_free)(struct snd_i2c_device *device);
  };
  
  #define snd_i2c_device(n) list_entry(n, struct snd_i2c_device, list)
  
  struct snd_i2c_bit_ops {
  	void (*start)(struct snd_i2c_bus *bus);	/* transfer start */
  	void (*stop)(struct snd_i2c_bus *bus);	/* transfer stop */
  	void (*direction)(struct snd_i2c_bus *bus, int clock, int data);  /* set line direction (0 = write, 1 = read) */
  	void (*setlines)(struct snd_i2c_bus *bus, int clock, int data);
  	int (*getclock)(struct snd_i2c_bus *bus);
  	int (*getdata)(struct snd_i2c_bus *bus, int ack);

  };

  struct snd_i2c_ops {
  	int (*sendbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
  	int (*readbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
  	int (*probeaddr)(struct snd_i2c_bus *bus, unsigned short addr);
  };
  
  struct snd_i2c_bus {
  	struct snd_card *card;	/* card which I2C belongs to */

  	char name[32];		/* some useful label */

  	struct mutex lock_mutex;

  	struct snd_i2c_bus *master;	/* master bus when SCK/SCL is shared */

  	struct list_head buses;	/* master: slave buses sharing SCK/SCL, slave: link list */
  
  	struct list_head devices; /* attached devices to this bus */
  
  	union {

  		struct snd_i2c_bit_ops *bit;

  		void *ops;
  	} hw_ops;		/* lowlevel operations */

  	struct snd_i2c_ops *ops;	/* midlevel operations */

  
  	unsigned long private_value;
  	void *private_data;

  	void (*private_free)(struct snd_i2c_bus *bus);

  };

  #define snd_i2c_slave_bus(n) list_entry(n, struct snd_i2c_bus, buses)

  int snd_i2c_bus_create(struct snd_card *card, const char *name,
  		       struct snd_i2c_bus *master, struct snd_i2c_bus **ri2c);
  int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name,
  			  unsigned char addr, struct snd_i2c_device **rdevice);
  int snd_i2c_device_free(struct snd_i2c_device *device);

  static inline void snd_i2c_lock(struct snd_i2c_bus *bus)
  {

  	if (bus->master)

  		mutex_lock(&bus->master->lock_mutex);

  	else

  		mutex_lock(&bus->lock_mutex);

  }

  
  static inline void snd_i2c_unlock(struct snd_i2c_bus *bus)
  {

  	if (bus->master)

  		mutex_unlock(&bus->master->lock_mutex);

  	else

  		mutex_unlock(&bus->lock_mutex);

  }

  int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
  int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
  int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr);

  
  #endif /* __SOUND_I2C_H */