海思的i2c写函数问题

海思的IIC函数:hi_i2c_master_send(client, buf, idx);
当寄存器reg_addr_num 为1,write_num为2时可以正常写入,为1时不能写入,大余2时,还是写成功两个字节,现在想要一次性写入多个字节,怎么解决呢?

int hi_i2c_write_nbyte(unsigned char i2c_bus,unsigned char devaddress,unsigned int reg_addr, unsigned int reg_addr_num, unsigned char *pdata, unsigned int data_byte_num) 
{ 
    unsigned char buf[256]; 
    int ret = 0,i,write_num; 
    int idx = 0; 
    struct i2c_client *client;

    write_num=data_byte_num;
    if(write_num>256)
    {
        printk("i2c write can write 256 data\n");
        write_num=256;
    }
    if(i2c_bus==1)
        client = I2C1_client; 
    else if(i2c_bus==2)
        client = I2C2_client; 
    else if(i2c_bus==3)
        client = I2C3_client; 
    else if(i2c_bus==4)
        client = I2C4_client; 
    else
        client = I2C1_client; 
    
    client->addr=devaddress; 
    /* reg_addr config */ 
    if (reg_addr_num == 2) 
    buf[idx++]  = (reg_addr >> 8); 
    buf[idx++] = reg_addr; 

    /* data config */ 
    for(i=0;i<write_num;i++)
    {
        buf[idx++] = pdata[i];
    }
    ret = hi_i2c_master_send(client, buf, idx); 
    
    return ret;    
}

你好,你可以看下海思底层驱动,对I2C怎么完成发送和读取的,参考下这篇文章:https://blog.csdn.net/rjszcb/article/details/112345480