i2c.h

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/* SPDX-License-Identifier: BSD-2-Clause */

 
/*
 * Copyright (C) 2014, 2017 embedded brains GmbH & Co. KG
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
 
#ifndef _DEV_I2C_I2C_H
#define _DEV_I2C_I2C_H
 
#include <linux/i2c.h>
#include <linux/i2c-dev.h>
 
#include <rtems.h>
#include <rtems/seterr.h>
#include <rtems/thread.h>
 
#include <sys/ioctl.h>
#include <sys/stat.h>
 
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
 
typedef struct i2c_msg i2c_msg;
 
typedef struct i2c_bus i2c_bus;
 
typedef struct i2c_dev i2c_dev;
 
typedef struct i2c_rdwr_ioctl_data i2c_rdwr_ioctl_data;




#define I2C_BUS_OBTAIN 0x800

#define I2C_BUS_RELEASE 0x801

#define I2C_BUS_GET_CONTROL 0x802

#define I2C_BUS_SET_CLOCK 0x803


#define I2C_BUS_CLOCK_DEFAULT 100000

struct i2c_bus {
  int (*transfer)(i2c_bus *bus, i2c_msg *msgs, uint32_t msg_count);

  int (*set_clock)(i2c_bus *bus, unsigned long clock);

  void (*destroy)(i2c_bus *bus);

  rtems_recursive_mutex mutex;

  uint16_t default_address;

  bool ten_bit_address;

  bool use_pec;

  unsigned long retries;

  rtems_interval timeout;

  unsigned long functionality;
};

int i2c_bus_init(i2c_bus *bus);

i2c_bus *i2c_bus_alloc_and_init(size_t size);

void i2c_bus_destroy(i2c_bus *bus);

void i2c_bus_destroy_and_free(i2c_bus *bus);

int i2c_bus_register(
  i2c_bus *bus,
  const char *bus_path
);

int i2c_bus_try_obtain(i2c_bus *bus);

void i2c_bus_obtain(i2c_bus *bus);

void i2c_bus_release(i2c_bus *bus);

int i2c_bus_transfer(i2c_bus *bus, i2c_msg *msgs, uint32_t msg_count);

int i2c_bus_do_transfer(
  i2c_bus *bus,
  i2c_msg *msgs,
  uint32_t msg_count,
  uint32_t flags
);

#define I2C_BUS_NOBLOCK (1u << 0)



#define I2C_DEV_IO_CONTROL 0x900

struct i2c_dev {
  ssize_t (*read)(i2c_dev *dev, void *buf, size_t n, off_t offset);

  ssize_t (*write)(i2c_dev *dev, const void *buf, size_t n, off_t offset);

  int (*ioctl)(i2c_dev *dev, ioctl_command_t command, void *arg);

  off_t (*get_size)(i2c_dev *dev);

  blksize_t (*get_block_size)(i2c_dev *dev);

  void (*destroy)(i2c_dev *dev);

  i2c_bus *bus;

  uint16_t address;

  int bus_fd;
};
 

int i2c_dev_init(i2c_dev *dev, const char *bus_path, uint16_t address);

i2c_dev *i2c_dev_alloc_and_init(
  size_t size,
  const char *bus_path,
  uint16_t address
);

void i2c_dev_destroy(i2c_dev *dev);

void i2c_dev_destroy_and_free(i2c_dev *dev);

int i2c_dev_register(
  i2c_dev *dev,
  const char *dev_path
);
  /* end of i2c device driver */

 
#ifdef __cplusplus
}
#endif /* __cplusplus */
 
#endif /* _DEV_I2C_I2C_H */