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 typedef struct _snd_i2c_device snd_i2c_device_t;
  25 typedef struct _snd_i2c_bus snd_i2c_bus_t;
  26
  27 #define SND_I2C_DEVICE_ADDRTEN  (1<<0)  /* 10-bit I2C address */
  28
  29 struct _snd_i2c_device {
  30         struct list_head list;
  31         snd_i2c_bus_t *bus;     /* I2C bus */
  32         char name[32];          /* some useful device name */
  33         unsigned short flags;   /* device flags */
  34         unsigned short addr;    /* device address (might be 10-bit) */
  35         unsigned long private_value;
  36         void *private_data;
  37         void (*private_free)(snd_i2c_device_t *device);
  38 };
  39
  40 #define snd_i2c_device(n) list_entry(n, snd_i2c_device_t, list)
  41
  42 typedef struct _snd_i2c_bit_ops {
  43         void (*start)(snd_i2c_bus_t *bus);      /* transfer start */
  44         void (*stop)(snd_i2c_bus_t *bus);       /* transfer stop */
  45         void (*direction)(snd_i2c_bus_t *bus, int clock, int data);  /* set line direction (0 = write, 1 = read) */
  46         void (*setlines)(snd_i2c_bus_t *bus, int clock, int data);
  47         int (*getclock)(snd_i2c_bus_t *bus);
  48         int (*getdata)(snd_i2c_bus_t *bus, int ack);
  49 } snd_i2c_bit_ops_t;
  50
  51 typedef struct _snd_i2c_ops {
  52         int (*sendbytes)(snd_i2c_device_t *device, unsigned char *bytes, int count);
  53         int (*readbytes)(snd_i2c_device_t *device, unsigned char *bytes, int count);
  54         int (*probeaddr)(snd_i2c_bus_t *bus, unsigned short addr);
  55 } snd_i2c_ops_t;
  56
  57 struct _snd_i2c_bus {
  58         snd_card_t *card;       /* card which I2C belongs to */
  59         char name[32];          /* some useful label */
  60
  61         struct semaphore lock_mutex;
  62
  63         snd_i2c_bus_t *master;  /* master bus when SCK/SCL is shared */
  64         struct list_head buses; /* master: slave buses sharing SCK/SCL, slave: link list */
  65
  66         struct list_head devices; /* attached devices to this bus */
  67
  68         union {
  69                 snd_i2c_bit_ops_t *bit;
  70                 void *ops;
  71         } hw_ops;               /* lowlevel operations */
  72         snd_i2c_ops_t *ops;     /* midlevel operations */
  73
  74         unsigned long private_value;
  75         void *private_data;
  76         void (*private_free)(snd_i2c_bus_t *bus);
  77 };
  78
  79 #define snd_i2c_slave_bus(n) list_entry(n, snd_i2c_bus_t, buses)
  80
  81 int snd_i2c_bus_create(snd_card_t *card, const char *name, snd_i2c_bus_t *master, snd_i2c_bus_t **ri2c);
  82 int snd_i2c_device_create(snd_i2c_bus_t *bus, const char *name, unsigned char addr, snd_i2c_device_t **rdevice);
  83 int snd_i2c_device_free(snd_i2c_device_t *device);
  84
  85 static inline void snd_i2c_lock(snd_i2c_bus_t *bus) {
  86         if (bus->master)
  87                 down(&bus->master->lock_mutex);
  88         else
  89                 down(&bus->lock_mutex);
  90 }
  91 static inline void snd_i2c_unlock(snd_i2c_bus_t *bus) {
  92         if (bus->master)
  93                 up(&bus->master->lock_mutex);
  94         else
  95                 up(&bus->lock_mutex);
  96 }
  97
  98 int snd_i2c_sendbytes(snd_i2c_device_t *device, unsigned char *bytes, int count);
  99 int snd_i2c_readbytes(snd_i2c_device_t *device, unsigned char *bytes, int count);
 100 int snd_i2c_probeaddr(snd_i2c_bus_t *bus, unsigned short addr);
 101
 102 #endif /* __SOUND_I2C_H */