写一个iic的Linux驱动

以下是一个简单的 I2C 驱动程序，实现了 I2C 总线的初始化、读写操作：

#include <linux/init.h>
#include <linux/module.h>
#include <linux/i2c.h>

static struct i2c_adapter *i2c_adap;
static struct i2c_client *i2c_client;

static int my_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
    printk("my_i2c_probe called\n");
    return 0;
}

static int my_i2c_remove(struct i2c_client *client)
{
    printk("my_i2c_remove called\n");
    return 0;
}

static const struct i2c_device_id my_i2c_id[] = {
    { "my_i2c_device", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, my_i2c_id);

static struct i2c_driver my_i2c_driver = {
    .driver = {
        .name = "my_i2c_driver",
        .owner = THIS_MODULE,
    },
    .probe = my_i2c_probe,
    .remove = my_i2c_remove,
    .id_table = my_i2c_id,
};

static int __init my_i2c_init(void)
{
    int ret;

    i2c_adap = i2c_get_adapter(0);
    if (!i2c_adap) {
        printk(KERN_ERR "Failed to get I2C adapter\n");
        return -ENODEV;
    }

    i2c_client = i2c_new_device(i2c_adap, &my_i2c_id[0]);
    if (!i2c_client) {
        printk(KERN_ERR "Failed to create I2C device\n");
        i2c_put_adapter(i2c_adap);
        return -ENODEV;
    }

    ret = i2c_add_driver(&my_i2c_driver);
    if (ret) {
        printk(KERN_ERR "Failed to add I2C driver\n");
        i2c_unregister_device(i2c_client);
        i2c_put_adapter(i2c_adap);
        return ret;
    }

    return 0;
}

static void __exit my_i2c_exit(void)
{
    i2c_del_driver(&my_i2c_driver);
    i2c_unregister_device(i2c_client);
    i2c_put_adapter(i2c_adap);
}

module_init(my_i2c_init);
module_exit(my_i2c_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("My I2C driver");

需要注意的是，这个驱动程序是一个简单的示例，可能需要根据实际情况进行修改。例如，需要实现 `my_i2c_probe` 和 `my_i2c_remove` 函数来处理设备的初始化和卸载操作，并且需要根据实际的硬件配置来初始化 I2C 总线。在实际项目中，还需要处理设备的读写操作等。