LXR linux/include/sound/i2c.h

   1#ifndef __SOUND_I2C_H
   2#define __SOUND_I2C_H
   3
   4/*
   5 *
   6 *
   7 *   This program is free software; you can redistribute it and/or modify
   8 *   it under the terms of the GNU General Public License as published by
   9 *   the Free Software Foundation; either version 2 of the License, or
  10 *   (at your option) any later version.
  11 *
  12 *   This program is distributed in the hope that it will be useful,
  13 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 *   GNU General Public License for more details.
  16 *
  17 *   You should have received a copy of the GNU General Public License
  18 *   along with this program; if not, write to the Free Software
  19 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20 *
  21 *
  22 */
  23
  24#define SND_I2C_DEVICE_ADDRTEN  (1<<0)  /* 10-bit I2C address */
  25
  26struct snd_i2c_device {
  27        struct list_head list;
  28        struct snd_i2c_bus *bus;        /* I2C bus */
  29        char name[32];          /* some useful device name */
  30        unsigned short flags;   /* device flags */
  31        unsigned short addr;    /* device address (might be 10-bit) */
  32        unsigned long private_value;
  33        void *private_data;
  34        void (*private_free)(struct snd_i2c_device *device);
  35};
  36
  37#define snd_i2c_device(n) list_entry(n, struct snd_i2c_device, list)
  38
  39struct snd_i2c_bit_ops {
  40        void (*start)(struct snd_i2c_bus *bus); /* transfer start */
  41        void (*stop)(struct snd_i2c_bus *bus);  /* transfer stop */
  42        void (*direction)(struct snd_i2c_bus *bus, int clock, int data);  /* set line direction (0 = write, 1 = read) */
  43        void (*setlines)(struct snd_i2c_bus *bus, int clock, int data);
  44        int (*getclock)(struct snd_i2c_bus *bus);
  45        int (*getdata)(struct snd_i2c_bus *bus, int ack);
  46};
  47
  48struct snd_i2c_ops {
  49        int (*sendbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
  50        int (*readbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
  51        int (*probeaddr)(struct snd_i2c_bus *bus, unsigned short addr);
  52};
  53
  54struct snd_i2c_bus {
  55        struct snd_card *card;  /* card which I2C belongs to */
  56        char name[32];          /* some useful label */
  57
  58        struct mutex lock_mutex;
  59
  60        struct snd_i2c_bus *master;     /* master bus when SCK/SCL is shared */
  61        struct list_head buses; /* master: slave buses sharing SCK/SCL, slave: link list */
  62
  63        struct list_head devices; /* attached devices to this bus */
  64
  65        union {
  66                struct snd_i2c_bit_ops *bit;
  67                void *ops;
  68        } hw_ops;               /* lowlevel operations */
  69        const struct snd_i2c_ops *ops;  /* midlevel operations */
  70
  71        unsigned long private_value;
  72        void *private_data;
  73        void (*private_free)(struct snd_i2c_bus *bus);
  74};
  75
  76#define snd_i2c_slave_bus(n) list_entry(n, struct snd_i2c_bus, buses)
  77
  78int snd_i2c_bus_create(struct snd_card *card, const char *name,
  79                       struct snd_i2c_bus *master, struct snd_i2c_bus **ri2c);
  80int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name,
  81                          unsigned char addr, struct snd_i2c_device **rdevice);
  82int snd_i2c_device_free(struct snd_i2c_device *device);
  83
  84static inline void snd_i2c_lock(struct snd_i2c_bus *bus)
  85{
  86        if (bus->master)
  87                mutex_lock(&bus->master->lock_mutex);
  88        else
  89                mutex_lock(&bus->lock_mutex);
  90}
  91
  92static inline void snd_i2c_unlock(struct snd_i2c_bus *bus)
  93{
  94        if (bus->master)
  95                mutex_unlock(&bus->master->lock_mutex);
  96        else
  97                mutex_unlock(&bus->lock_mutex);
  98}
  99
 100int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
 101int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
 102int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr);
 103
 104#endif /* __SOUND_I2C_H */
 105