76 lines
1.7 KiB
C
76 lines
1.7 KiB
C
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/miscdevice.h>
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#include <linux/fs.h>
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#include <linux/types.h>
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#include <linux/moduleparam.h>
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#include <linux/slab.h>
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#include <linux/cdev.h>
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#include <linux/gpio.h>
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#include <linux/of_gpio.h>
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#include <asm/uaccess.h>
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#include "ds18b20.h"
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#define DEVICE_NAME "ds18b20-223"
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#define NODE_NAME "ds18b20-223"
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#define gpio_num 223
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static int ds18b20_open(struct inode *inode, struct file *filp)
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{
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//printk (KERN_INFO "Device opened\n");
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int flag = initDs18b20(gpio_num);
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if(flag & 0x01)
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return -1;
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return 0;
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}
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/*读取数据*/
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static int ds18b20_read(struct file *filp, char __user *buffer, size_t count, loff_t *ppos)
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{
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unsigned char tmp[2];
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readDs18b20Data(tmp);
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return copy_to_user(buffer, &tmp, sizeof(tmp));
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}
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static struct file_operations ds18b20_fops = {
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.owner = THIS_MODULE,
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.open = ds18b20_open,
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.read = ds18b20_read,
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};
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static struct miscdevice ds18b20_dev = {
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.minor = MISC_DYNAMIC_MINOR,
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.name = DEVICE_NAME,
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.nodename = NODE_NAME,
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.fops = &ds18b20_fops,
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};
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static int __init ds18b20_dev_init(void) {
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int ret;
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ret = gpio_request(gpio_num, DEVICE_NAME);
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if (ret) {
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printk("%s: request GPIO %d for GPE0 failed, ret = %d\n", DEVICE_NAME, gpio_num, ret);
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return ret;
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}
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ret = misc_register(&ds18b20_dev);//注册杂设备驱动
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printk(DEVICE_NAME"\tinitialized\n");
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return ret;
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}
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static void __exit ds18b20_dev_exit(void) {
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freeDs18b20();
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misc_deregister(&ds18b20_dev);
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}
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module_init(ds18b20_dev_init);
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module_exit(ds18b20_dev_exit);
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MODULE_LICENSE("GPL");
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MODULE_VERSION("1.0");
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MODULE_AUTHOR("shuixx.");
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