linux spi驱动控制icm20608的代码

以下是一个简单的示例代码，用于在Linux上使用SPI驱动程序控制ICM20608传感器：

#include <linux/spi/spi.h>

#define ICM20608_REG_WHO_AM_I   0x75
#define ICM20608_WHO_AM_I_VAL   0xAF
#define ICM20608_REG_PWR_MGMT_1 0x6B
#define ICM20608_PWR_MGMT_1_VAL 0x00

static struct spi_device *icm20608_spi_device;

static int icm20608_spi_init(void)
{
    struct spi_master *master;
    struct spi_device *spi_dev;
    struct spi_board_info spi_board = {
        .modalias = "icm20608",
        .max_speed_hz = 5000000,
        .bus_num = 1,
        .chip_select = 0,
        .mode = SPI_MODE_0,
    };

    master = spi_busnum_to_master(spi_board.bus_num);
    if (!master) {
        printk(KERN_ERR "Failed to get SPI master\n");
        return -ENODEV;
    }

    spi_dev = spi_new_device(master, &spi_board);
    if (!spi_dev) {
        printk(KERN_ERR "Failed to create SPI device\n");
        return -ENODEV;
    }

    icm20608_spi_device = spi_dev;

    return 0;
}

static void icm20608_spi_exit(void)
{
    spi_unregister_device(icm20608_spi_device);
}

static int icm20608_spi_read_byte(unsigned char reg, unsigned char *val)
{
    int ret;
    unsigned char tx_buf[2];
    unsigned char rx_buf[2];

    tx_buf[0] = reg | 0x80;
    tx_buf[1] = 0x00;

    ret = spi_sync_transfer(icm20608_spi_device, tx_buf, rx_buf, 2);
    if (ret < 0) {
        printk(KERN_ERR "SPI read failed\n");
        return ret;
    }

    *val = rx_buf[1];

    return 0;
}

static int icm20608_spi_write_byte(unsigned char reg, unsigned char val)
{
    int ret;
    unsigned char tx_buf[2];
    unsigned char rx_buf[2];

    tx_buf[0] = reg & 0x7F;
    tx_buf[1] = val;

    ret = spi_sync_transfer(icm20608_spi_device, tx_buf, rx_buf, 2);
    if (ret < 0) {
        printk(KERN_ERR "SPI write failed\n");
        return ret;
    }

    return 0;
}

static int icm20608_spi_probe(struct spi_device *spi_dev)
{
    int ret;
    unsigned char val;

    printk(KERN_INFO "ICM20608 SPI probe\n");

    ret = icm20608_spi_read_byte(ICM20608_REG_WHO_AM_I, &val);
    if (ret < 0) {
        printk(KERN_ERR "ICM20608 SPI read WHO_AM_I failed\n");
        return ret;
    }

    if (val != ICM20608_WHO_AM_I_VAL) {
        printk(KERN_ERR "ICM20608 WHO_AM_I value mismatch\n");
        return -EIO;
    }

    ret = icm20608_spi_write_byte(ICM20608_REG_PWR_MGMT_1, ICM20608_PWR_MGMT_1_VAL);
    if (ret < 0) {
        printk(KERN_ERR "ICM20608 SPI write PWR_MGMT_1 failed\n");
        return ret;
    }

    return 0;
}

static int icm20608_spi_remove(struct spi_device *spi_dev)
{
    printk(KERN_INFO "ICM20608 SPI remove\n");

    return 0;
}

static struct spi_driver icm20608_spi_driver = {
    .driver = {
        .name = "icm20608",
        .owner = THIS_MODULE,
    },
    .probe = icm20608_spi_probe,
    .remove = icm20608_spi_remove,
};

static int __init icm20608_spi_init_module(void)
{
    int ret;

    printk(KERN_INFO "ICM20608 SPI driver init\n");

    ret = icm20608_spi_init();
    if (ret < 0) {
        printk(KERN_ERR "Failed to initialize ICM20608 SPI\n");
        return ret;
    }

    ret = spi_register_driver(&icm20608_spi_driver);
    if (ret < 0) {
        printk(KERN_ERR "Failed to register ICM20608 SPI driver\n");
        icm20608_spi_exit();
        return ret;
    }

    return 0;
}

static void __exit icm20608_spi_exit_module(void)
{
    printk(KERN_INFO "ICM20608 SPI driver exit\n");

    spi_unregister_driver(&icm20608_spi_driver);

    icm20608_spi_exit();
}

module_init(icm20608_spi_init_module);
module_exit(icm20608_spi_exit_module);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Your name");
MODULE_DESCRIPTION("ICM20608 SPI driver"); 

这个驱动程序初始化SPI总线和设备，并提供了读取和写入ICM20608寄存器的函数。在`probe`函数中，将读取WHO_AM_I寄存器的值，并验证其是否与预期值匹配。然后写入PWR_MGMT_1寄存器以使ICM20608处于激活状态。