Linux驅動編譯進核心-GPIO驅動

OK6410_leds.c如下：

#include <linux/miscdevice.h>
#include <linux/delay.h>
#include <asm/irq.h>
#include <mach/hardware.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <asm/uaccess.h>
#include <asm/atomic.h>
#include <asm/unistd.h>
#include <mach/map.h>
#include <mach/regs-clock.h>
#include <mach/regs-gpio.h>
#include <plat/gpio-cfg.h>
#include <mach/gpio-bank-e.h>
#include <mach/gpio-bank-m.h>

#define DEVICE_NAME "leds_wuwen"

static long s3c6410_leds_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
switch(cmd) {
unsigned tmp;
case 0:
case 1:
if (arg > 4)
{
return -EINVAL;
}
tmp = readl(S3C64XX_GPMDAT);

if(cmd==0) //close light
{
tmp &= (~(1<<arg));
}
else //open light
{
tmp |= (1<<arg);
}

writel(tmp,S3C64XX_GPMDAT);

printk (DEVICE_NAME": %d %d\n", arg, cmd);
return 0;
default:
return -EINVAL;
}
}

static struct file_operations dev_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = s3c6410_leds_ioctl,
};

static struct miscdevice misc = {
.minor = MISC_DYNAMIC_MINOR,
.name = DEVICE_NAME,
.fops = &dev_fops,
};

static int __init dev_init(void)
{
int ret;

unsigned tmp;

//gpm0-3 pull up
tmp = readl(S3C64XX_GPMPUD);
tmp &= (~0xFF);
tmp |= 0xaa;
writel(tmp,S3C64XX_GPMPUD);

//gpm0-3 output mode
tmp =readl(S3C64XX_GPMCON);
tmp &= (~0xFFFF);
tmp |= 0x1111;
writel(tmp,S3C64XX_GPMCON);

//gpm0-3 output 0
tmp = __raw_readl(S3C64XX_GPMDAT);
tmp |= 0x10;
writel(tmp,S3C64XX_GPMDAT);

ret = misc_register(&misc);

return ret;
}

static void __exit dev_exit(void)
{
misc_deregister(&misc);
}

module_init(dev_init);
module_exit(dev_exit);
MODULE_LICENSE("GPL");
           

将OK6410_leds.c轉移到/drivers/char下

gedit Kconfig

加入

config MY_LEDS

     tristale "Shine_led"

     depend on ARCH_S3C64xx

編輯Makefile

加入

obj-$(CONFIG_MY_LEDS)                  +=OK6410_leds.o

make menuconfig

進入Devices drivers --》 character drivers 将Shine_leds選中：<*>

make zImage

led_test.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

int main (int argc,char **argv)
{
int fd;
int led_num;
int on;
sscanf(argv[1],"%d",&led_num);
sscanf(argv[2],"%d",&on);
fd = open("/dev/leds_wuwen",O_RDWR);
if (fd < 0)
{
printf ("Open /dev/leds_wuwen file error\n");
return -1;
}

ioctl(fd,on,led_num);
close (fd);
return 0;

}
           

編譯生成可執行檔案，交叉編譯

啟動系統。

檢視裝置 ls -l dev

leds_wuwen已經挂上

輸入./led_test 0 1 就是0号燈滅

./led_test 2 0 就是2号燈變亮