i2c 与 spi 设备在新版内核中不采用DTS设备树形式 在驱动添加设备信息(board_info)的方法

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/*
废话：在展讯平台移植 spi 设备的时候发现完成 dts 和 driver中的 of_match_table 后，在 init时 spi_driver_register 返回0（注册成功）但是 probe 却无法跑起来，一直没有 找出来原因。
于是改用 board_info 的方式直接在 driver 中注册设备信息。
*/

i2c 设备模型

#include <linux/module.h>#include <linux/i2c.h>#define SENSOR_BUS_NUM 0#define SENSOR_SLAVE_ADDRESS 0x3e#define SENSOR_NAME "sensor"struct i2c_client *sensor_client=NULL;static int sensor_probe(struct i2c_client *client,const struct i2c_device_id *id){    sensor_client=client;    return 0;}static int sensor_remove(struct i2c_client *client){    return 0;}//首先需要一个 id_tablestatic const struct i2c_device_id sensor_id[] = {    {SENSOR_NAME, 0},    { }};MODULE_DEVICE_TABLE(i2c, sensor_id);//在 driver中添加 id_tablestatic struct i2c_driver sensor_driver = {    .driver = {             .name = SENSOR_NAME,    },    .probe    = sensor_probe,    .remove   = sensor_remove,    .id_table = sensor_id,};//填充 board_info static struct i2c_board_info sensor_device = {    I2C_BOARD_INFO("hmc5883l-i2c", SENSOR_SLAVE_ADDRESS),};static int __init sensor_init(void){    struct i2c_adapter *adap;    struct i2c_client *client;    adap = i2c_get_adapter(sensor_bus_num);    if (!adap) {        printk("i2c adapter %d\n",sensor_bus_num);        return -ENODEV;    } else {        printk("get ii2 adapter %d ok\n", sensor_bus_num);        client = i2c_new_device(adap, &sensor_device);    }    if (!client) {        printk("get i2c client %s @ 0x%02x fail!\n", sensor_device.type,                sensor_device.addr);        return -ENODEV;    } else {        printk("get i2c client ok!\n");    }    i2c_put_adapter(adap);    i2c_add_driver(&sensor_driver);    printk("sensor init success!\n");    return 0;}static void __exit sensor_exit(void){    i2c_del_driver(&sensor_driver);    if(sensor_client!=NULL)    i2c_unregister_device(sensor_client);    printk("Module removed\n");}module_init(sensor_init);module_exit(sensor_exit);ODULE_AUTHOR("GPL");ODULE_LICENSE("GPL");

spi设备驱动模型

spi的驱动模板如下

#include <linux/module.h>#include <linux/spi/spi.h>#define DEVICE_NAME   "sensor"#define SENSOR_SPI_BUS 0struct spi_device *sensor_spi=NULL;int sensor_spi_write(void){    return 0;}int sensor_spi_read(void){    return 0;}static const struct spi_device_id sensor_spi_id[] = {    { DEVICE_NAME, 0 },    { }};MODULE_DEVICE_TABLE(spi, sensor_spi_id);static int  sensor_probe(struct spi_device *spi){    sensor_spi=spi;    return 0;}static int  sensor_remove(struct spi_device *spi){    return 0;}static struct spi_driver sensor_driver = {    .driver = {        .name  = DEVICE_NAME,        .owner = THIS_MODULE,    },    .probe    =  sensor_probe,    .remove   =  sensor_remove,    .id_table =  sensor_spi_id,};static __init int sensor_spi_init(void){    int status=-1;    struct spi_master *master;    struct spi_device *spi;    struct spi_board_info chip =    {        .modalias     = DEVICE_NAME,        .mode         = 0x00,        .bus_num      = 0,        .chip_select  = 0,        .max_speed_hz = 2000000,    };    spi_register_driver(&sensor_driver);    if (status<0)    {        pr_err("%s: spi_register_driver spi_driver failure. status = %d\n", __func__, status);    }    pr_err("%s: spi_register_driver spi_driver success. status = %d\n", __func__, status);    master = spi_busnum_to_master(SENSOR_SPI_BUS);    if (!master)    {        status = -ENODEV;        goto error_busnum;    }    spi = spi_new_device(master, &chip);    if (!spi)    {        status = -EBUSY;        goto error_mem;    }    return status;error_mem:error_busnum:    spi_unregister_driver(&sensor_driver);    return status;}static __exit void sensor_spi_exit(void){    spi_unregister_driver(&sensor_driver);    if(sensor_spi!=NULL)    spi_unregister_device(sensor_spi);}module_init(sensor_spi_init);module_exit(sensor_spi_exit);MODULE_LICENSE("GPL v2");