LXR linux/include/sound/i2c.h

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2#ifndef __SOUND_I2C_H
   3#define __SOUND_I2C_H
   4
   5/*
   6 */
   7
   8#define SND_I2C_DEVICE_ADDRTEN  (1<<0)  /* 10-bit I2C address */
   9
  10struct snd_i2c_device {
  11        struct list_head list;
  12        struct snd_i2c_bus *bus;        /* I2C bus */
  13        char name[32];          /* some useful device name */
  14        unsigned short flags;   /* device flags */
  15        unsigned short addr;    /* device address (might be 10-bit) */
  16        unsigned long private_value;
  17        void *private_data;
  18        void (*private_free)(struct snd_i2c_device *device);
  19};
  20
  21#define snd_i2c_device(n) list_entry(n, struct snd_i2c_device, list)
  22
  23struct snd_i2c_bit_ops {
  24        void (*start)(struct snd_i2c_bus *bus); /* transfer start */
  25        void (*stop)(struct snd_i2c_bus *bus);  /* transfer stop */
  26        void (*direction)(struct snd_i2c_bus *bus, int clock, int data);  /* set line direction (0 = write, 1 = read) */
  27        void (*setlines)(struct snd_i2c_bus *bus, int clock, int data);
  28        int (*getclock)(struct snd_i2c_bus *bus);
  29        int (*getdata)(struct snd_i2c_bus *bus, int ack);
  30};
  31
  32struct snd_i2c_ops {
  33        int (*sendbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
  34        int (*readbytes)(struct snd_i2c_device *device, unsigned char *bytes, int count);
  35        int (*probeaddr)(struct snd_i2c_bus *bus, unsigned short addr);
  36};
  37
  38struct snd_i2c_bus {
  39        struct snd_card *card;  /* card which I2C belongs to */
  40        char name[32];          /* some useful label */
  41
  42        struct mutex lock_mutex;
  43
  44        struct snd_i2c_bus *master;     /* master bus when SCK/SCL is shared */
  45        struct list_head buses; /* master: slave buses sharing SCK/SCL, slave: link list */
  46
  47        struct list_head devices; /* attached devices to this bus */
  48
  49        union {
  50                struct snd_i2c_bit_ops *bit;
  51                void *ops;
  52        } hw_ops;               /* lowlevel operations */
  53        const struct snd_i2c_ops *ops;  /* midlevel operations */
  54
  55        unsigned long private_value;
  56        void *private_data;
  57        void (*private_free)(struct snd_i2c_bus *bus);
  58};
  59
  60#define snd_i2c_slave_bus(n) list_entry(n, struct snd_i2c_bus, buses)
  61
  62int snd_i2c_bus_create(struct snd_card *card, const char *name,
  63                       struct snd_i2c_bus *master, struct snd_i2c_bus **ri2c);
  64int snd_i2c_device_create(struct snd_i2c_bus *bus, const char *name,
  65                          unsigned char addr, struct snd_i2c_device **rdevice);
  66int snd_i2c_device_free(struct snd_i2c_device *device);
  67
  68static inline void snd_i2c_lock(struct snd_i2c_bus *bus)
  69{
  70        if (bus->master)
  71                mutex_lock(&bus->master->lock_mutex);
  72        else
  73                mutex_lock(&bus->lock_mutex);
  74}
  75
  76static inline void snd_i2c_unlock(struct snd_i2c_bus *bus)
  77{
  78        if (bus->master)
  79                mutex_unlock(&bus->master->lock_mutex);
  80        else
  81                mutex_unlock(&bus->lock_mutex);
  82}
  83
  84int snd_i2c_sendbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
  85int snd_i2c_readbytes(struct snd_i2c_device *device, unsigned char *bytes, int count);
  86int snd_i2c_probeaddr(struct snd_i2c_bus *bus, unsigned short addr);
  87
  88#endif /* __SOUND_I2C_H */
  89