tiny6410温度传感器驱动学习1（测试通过）

来源：互联网发布：程序员自由职业平台编辑：程序博客网时间：2024/05/02 00:02

参考http://www.arm9home.net/read.php?tid-16249.html的驱动代码如下

#include    <linux/module.h>#include    <linux/fs.h>#include    <linux/kernel.h>#include    <linux/init.h>#include    <linux/delay.h>#include    <linux/cdev.h>#include    <linux/device.h>#include    <linux/gpio.h>#include    <plat/gpio-cfg.h>#define    DEVICE_NAME "temp"  //设备名字static struct cdev cdev;   struct class *tem_class;static dev_t devno;static int major = 243;void tem_reset(void){    s3c_gpio_cfgpin(S3C64XX_GPN(8), S3C_GPIO_SFN(1));    gpio_set_value(S3C64XX_GPN(8), 1);    udelay(100);    gpio_set_value(S3C64XX_GPN(8), 0);    udelay(600);    gpio_set_value(S3C64XX_GPN(8), 1);    udelay(100);    s3c_gpio_cfgpin(S3C64XX_GPN(8), S3C_GPIO_SFN(0));}void tem_wbyte(unsigned char data){    int i;    s3c_gpio_cfgpin(S3C64XX_GPN(8), S3C_GPIO_SFN(1));    for (i = 0; i < 8; ++i)    {        gpio_set_value(S3C64XX_GPN(8), 0);        udelay(1);        if (data & 0x01)        {            gpio_set_value(S3C64XX_GPN(8), 1);        }        udelay(60);        gpio_set_value(S3C64XX_GPN(8), 1);        udelay(15);        data >>= 1;    }    gpio_set_value(S3C64XX_GPN(8), 1);}unsigned char tem_rbyte(void){    int i;    unsigned char ret = 0;    for (i = 0; i < 8; ++i)    {        s3c_gpio_cfgpin(S3C64XX_GPN(8), S3C_GPIO_SFN(1));        gpio_set_value(S3C64XX_GPN(8), 0);        udelay(1);        gpio_set_value(S3C64XX_GPN(8), 1);        s3c_gpio_cfgpin(S3C64XX_GPN(8), S3C_GPIO_SFN(0));        ret >>= 1;        if (gpio_get_value(S3C64XX_GPN(8)))        {            ret |= 0x80;            }        udelay(60);    }    s3c_gpio_cfgpin(S3C64XX_GPN(8), S3C_GPIO_SFN(1));    return ret;}static ssize_t tem_read(struct file *filp, char *buf, size_t len, loff_t *offset){    unsigned char low, high;    tem_reset();    udelay(420);    tem_wbyte(0xcc);    tem_wbyte(0x44);    mdelay(750);    tem_reset();    udelay(400);    tem_wbyte(0xcc);    tem_wbyte(0xbe);    low = tem_rbyte();    high = tem_rbyte();    *buf = low / 16 + high * 16;    *(buf + 1) = (low & 0x0f) * 10 / 16 + (high & 0x0f) * 100 / 16 % 10;    return 0;}static struct file_operations tem_fops = {    .owner    = THIS_MODULE,    .read    = tem_read,};static int __init tem_init(void){    int result;    devno = MKDEV(major, 0);    result = register_chrdev_region(devno, 1, DEVICE_NAME);    if (result)    {        printk("register failed\n");            return result;    }    cdev_init(&cdev, &tem_fops);    cdev.owner = THIS_MODULE;    cdev.ops = &tem_fops;    result = cdev_add(&cdev, devno, 1);    if (result)    {        printk("cdev add failed\n");            goto fail1;    }    tem_class = class_create(THIS_MODULE, "tmp_class");    if (IS_ERR(tem_class))    {        printk("class create failed\n");            goto fail2;    }    device_create(tem_class, NULL, devno, DEVICE_NAME, DEVICE_NAME);    return 0;fail2:    cdev_del(&cdev);fail1:    unregister_chrdev_region(devno, 1);    return result;}static void __exit tem_exit(void){    device_destroy(tem_class, devno);    class_destroy(tem_class);    cdev_del(&cdev);    unregister_chrdev_region(devno, 1);}module_init(tem_init);module_exit(tem_exit);MODULE_LICENSE("GPL");MODULE_AUTHOR(nanjizhiyin@sina.com);

#include "stdio.h"#include "sys/types.h"#include "sys/ioctl.h"#include "stdlib.h"#include "termios.h"#include "sys/stat.h"#include "fcntl.h"#include "sys/time.h"main(){    int fd;    unsigned char buf[2];    if ((fd=open("/dev/temp",O_RDWR | O_NDELAY | O_NOCTTY)) < 0)    {        printf("Open Device DS18B20 failed.\r\n");        exit(1);    }    else    {        printf("Open Device DS18B20 successed.\r\n");        while(1)        {            read(fd, buf, sizeof(buf));            printf("%d.%dC\r\n", buf[0], buf[1]);            sleep(1);        }        close(fd);    }}