rt-thread-official/bsp/loongson/ls1cdev/drivers/drv_i2c.c

/*
 * Copyright (c) 2006-2018, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2017-11-14     勤为本       first version
 */

#include <rtthread.h>
#include <drivers/dev_i2c.h>
#include <drivers/dev_i2c_bit_ops.h>
#include "drv_i2c.h"
#include "../libraries/ls1c_gpio.h"
#include "../libraries/ls1c_delay.h"


#define LS1C_I2C_SCL                (51)    // gpio57
#define LS1C_I2C_SDA                (50)    // gpio56

#define LS1C_SET_GPIO_MODE

static void ls1c_i2c_gpio_init(void)
{
    gpio_init(LS1C_I2C_SCL, gpio_mode_output);
    gpio_set(LS1C_I2C_SCL, gpio_level_high);

    gpio_init(LS1C_I2C_SDA, gpio_mode_output);
    gpio_set(LS1C_I2C_SDA, gpio_level_high);

    return ;
}


static void ls1c_udelay(rt_uint32_t us)
{
    delay_us((int)us);
}


static void ls1c_set_sda(void *data, rt_int32_t state)
{
#ifdef LS1C_SET_GPIO_MODE
    gpio_init(LS1C_I2C_SDA, gpio_mode_output);
    ls1c_udelay(5);
#endif
    gpio_set(LS1C_I2C_SDA, state);
    return ;
}


static void ls1c_set_scl(void *data, rt_int32_t state)
{
#ifdef LS1C_SET_GPIO_MODE
    gpio_init(LS1C_I2C_SCL, gpio_mode_output);
    ls1c_udelay(5);
#endif
    gpio_set(LS1C_I2C_SCL, state);
    return ;
}


static rt_int32_t ls1c_get_sda(void *data)
{
#ifdef LS1C_SET_GPIO_MODE
    gpio_init(LS1C_I2C_SDA, gpio_mode_input);
    ls1c_udelay(5);
#endif
    return gpio_get(LS1C_I2C_SDA);
}


static rt_int32_t ls1c_get_scl(void *data)
{
#ifdef LS1C_SET_GPIO_MODE
    gpio_init(LS1C_I2C_SCL, gpio_mode_input);
    ls1c_udelay(5);
#endif
    return gpio_get(LS1C_I2C_SCL);
}


static const struct rt_i2c_bit_ops bit_ops = 
{
    .data       = RT_NULL,
    .pin_init   = ls1c_i2c_gpio_init,
    .set_sda    = ls1c_set_sda,
    .set_scl    = ls1c_set_scl,
    .get_sda    = ls1c_get_sda,
    .get_scl    = ls1c_get_scl,
    .udelay     = ls1c_udelay,
    .delay_us   = 20,       // 此值为周期(us)
    .timeout    = 10,       // 单位为tick
    .i2c_pin_init_flag = RT_FALSE
};



int ls1c_i2c_init(void)
{
    static struct rt_i2c_bus_device bus = {0};

    bus.priv = (void *)&bit_ops;

    rt_i2c_bit_add_bus(&bus, "i2c3");

    return RT_EOK;
}