如何做一个基于硬件的LED灯驱动程序（GPIO）..docx

Led灯设备驱动类别。这个驱动应该是属于字符驱动，但是2.6内核里面细分为字符驱动里面的杂项（misc）设备驱动，因此用杂项设备驱动的结构，框架来编写led的驱动更恰当。二、应用层与设备交互流程（LED实验为实例）四、led驱动程序编写，源代码如下：#include linux/kernel.h#include linux/module.h#include linux/miscdevice.h#include linux/fs.h#include linux/types.h#include linux/moduleparam.h#include linux/slab.h#include linux/ioctl.h#include linux/cdev.h#include linux/delay.h#include mach/gpio.h#include mach/regs-gpio.h#include plat/gpio-cfg.h#define DEVICE_NAME LEDSstatic int led_gpios[] = {S5PV210_GPH2(0),S5PV210_GPH2(1),S5PV210_GPH2(2),S5PV210_GPH2(3),};#define LED_NUMARRAY_SIZE(led_gpios)static long fl210_leds_ioctl(struct file *filp, unsigned int cmd,unsigned long arg){switch(cmd) {case 0:case 1:if (arg LED_NUM) {return -EINVAL;}gpio_set_value(led_gpios[arg], !cmd);printk(DEVICE_NAME: %ld %d\n, arg, cmd);break;default:return -EINVAL;}return 0;}static struct file_operations fl210_led_dev_fops = {.owner= THIS_MODULE,.unlocked_ioctl= fl210_leds_ioctl,};static struct miscdevice fl210_led_dev = {.minor= MISC_DYNAMIC_MINOR,.name= DEVICE_NAME,.fops= fl210_led_dev_fops,};static int __init fl210_led_dev_init(void) {int ret;int i;for (i = 0; i LED_NUM; i++) {ret = gpio_request(led_gpios[i], LED);if (ret) {printk(%s: request GPIO %d for LED failed, ret = %d\n, DEVICE_NAME,led_gpios[i], ret);return ret;}s3c_gpio_cfgpin(led_gpios[i], S3C_GPIO_OUTPUT);gpio_set_value(led_gpios[i], 1);}ret = misc_register(fl210_led_dev);printk(DEVICE_NAME\tinitialized is ok!!\n);return ret;}static void __exit fl210_led_dev_exit(void) {int i;for (i = 0; i LED_NUM; i++) {gpio_free(led_gpios[i]);}misc_deregister(fl210_led_dev);printk(DEVICE_NAME\trmmod is ok!!\n);}module_init(fl210_led_dev_init);module_exit(fl210_led_dev_exit);MODULE_LICENSE(GPL);MODULE_AUTHOR(Forlinx Inc.);五、LED设备驱动应用程序测试#includestdio.h#includestdlib.hint main(int argc, char **argv){int fd;fd = open(/dev/gpm_leds,0);if(!fd){printf(==============fail %d==========\n,fd);return -1;}if((argc != 3) (argv[2] == 0)){printf(./xxx on/off nled\r\n./xxx 0 1\n)