/**********************************************************************
 *   Copyright: (C)2024 LingYun IoT System Studio
 *      Author: GuoWenxue<guowenxue@gmail.com>
 *
 * Description: The purpose of this code is to provide a simple C library,
 *              which providing software bit-bang of the I2C protocol on
 *              any GPIO pins for ISKBoard.
 *
 *   ChangeLog:
 *        Version    Date       Author            Description
 *        V1.0.0  2024.08.29    GuoWenxue      Release initial version
 *
 ***********************************************************************/

#ifndef __I2C_BITBANG_H_
#define __I2C_BITBANG_H_

#include "stm32l4xx_hal.h"

#define I2C_CLK_STRETCH_TIMEOUT   6000

/*
 *+---------------------------------+
 *|  I2C GPIO port Level functions  |
 *+---------------------------------+
 */

/* GPIO port for I2C typedef */
typedef struct i2c_gpio_s
{
    GPIO_TypeDef        *group; /* GPIO group */
    uint16_t             pin;   /* GPIO pin   */
} i2c_gpio_t;

/* I2C bus typedef */
typedef struct i2c_bus_s
{
    uint8_t             addr; /* 7-bits slave address */
    i2c_gpio_t          scl;  /* SCL GPIO pin */
    i2c_gpio_t          sda;  /* SDA GPIO pin */
} i2c_bus_t;


/*
 *+--------------------------------+
 *|  I2C High Level API functions  |
 *+--------------------------------+
 */

/* I2C bus error number */
enum
{
  ERROR_NONE     = 0x00, // no error
  ERROR_PARM     = 0x01, // parameter out of range error
  ERROR_ACK      = 0x02, // no acknowledgment error
  ERROR_TIMEOUT  = 0x03, // timeout error
  ERROR_CHECKSUM = 0x04, // checksum mismatch error
};

/* Set I2C slave device 7-bits address in the bus to lock it */
extern int i2c_lock(uint8_t addr);

/* Clear I2C slave device 7-bits address in the bus to free it */
extern void i2c_free(void);

/* write data by to slave device */
extern int i2c_write(uint8_t *data, int bytes);

/* read data from slave device */
extern int i2c_read(uint8_t *buf, int size);

/*
 *+--------------------------------+
 *|  I2C Low Level API functions   |
 *+--------------------------------+
 */

/* Send I2C start condition */
extern void I2C_StartCondition(void);

/* Send I2C stop condition */
extern void I2C_StopCondition(void);

/* Send I2C slave device 8-bits address */
#define W_ADDR(x)     ((x)<<1 )    /* I2C address bit[0]=0 means write */
#define R_ADDR(x)     ((x)<<1 | 1) /* I2C address bit[0]=1 means read  */
enum
{
    I2C_WR,  /* Direction for write */
    I2C_RD,  /* Direction for read  */
};
extern int I2C_SendAddress(uint8_t dir);

/* Write a byte data to I2C slave device */
extern int I2C_WriteByte(uint8_t txByte);

/* Read a byte data from I2C slave device */
enum
{
    ACK_NONE, /* ACK None */
    ACK,      /* ACK */
    NAK,      /* NAK */
};
extern int I2C_ReadByte(uint8_t *rxByte, uint8_t ack, uint32_t timeout);

#endif /* __I2C_BITBANG_H_ */