我發現我加入一個timer.c的driver進入核心,編譯也完成,
查看dmesg也有initialized.但是我呼叫open就是不會動作.
而這程式是由pwm.c修改而來,請大家看看到底問題在哪裡
==========mini2440_pwm.c====================
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <mach/regs-gpio.h>
#include <mach/hardware.h>
#include <plat/regs-timer.h>
#include <mach/regs-irq.h>
#include <asm/mach/time.h>
#include <linux/clk.h>
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/miscdevice.h>
#define DEVICE_NAME "pwm"
static struct semaphore lock;
static int s3c24xx_pwm_open(struct inode *inode, struct file *file)
{
printk("TEST_PWM_PRINTK \n");
if (!down_trylock(&lock))
return 0;
else
return -EBUSY;
}
static int s3c24xx_pwm_close(struct inode *inode, struct file *file)
{
up(&lock);
return 0;
}
static struct file_operations dev_fops = {
.owner = THIS_MODULE,
.open = s3c24xx_pwm_open,
.release = s3c24xx_pwm_close,
};
static struct miscdevice misc = {
.minor = MISC_DYNAMIC_MINOR,
.name = DEVICE_NAME,
.fops = &dev_fops,
};
static int __init dev_init(void)
{
int ret;
init_MUTEX(&lock);
ret = misc_register(&misc);
printk (DEVICE_NAME"\tinitialized\n");
return ret;
}
static void __exit dev_exit(void)
{
misc_deregister(&misc);
}
module_init(dev_init);
module_exit(dev_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("FriendlyARM Inc.");
MODULE_DESCRIPTION("S3C2410/S3C2440 PWM Driver");
==========mini2440_timer.c====================
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <mach/regs-gpio.h>
#include <mach/hardware.h>
#include <plat/regs-timer.h>
#include <mach/regs-irq.h>
#include <asm/mach/time.h>
#include <linux/clk.h>
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/miscdevice.h>
#define DEVICE_NAME "timer"
static struct semaphore lock;
static int s3c24xx_timer_open(struct inode *inode, struct file *file)
{
printk("TEST_TIMER_PRINTK \n");
if (!down_trylock(&lock))
return 0;
else
return -EBUSY;
}
static int s3c24xx_timer_close(struct inode *inode, struct file *file)
{
up(&lock);
return 0;
}
static struct file_operations dev_fops = {
.owner = THIS_MODULE,
.open = s3c24xx_timer_open,
.release = s3c24xx_timer_close,
};
static struct miscdevice misc = {
.minor = MISC_DYNAMIC_MINOR,
.name = DEVICE_NAME,
.fops = &dev_fops,
};
static int __init dev_init(void)
{
int ret;
init_MUTEX(&lock);
ret = misc_register(&misc);
printk (DEVICE_NAME"\tinitialized\n");
return ret;
}
static void __exit dev_exit(void)
{
misc_deregister(&misc);
}
module_init(dev_init);
module_exit(dev_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("FriendlyARM Inc.");
MODULE_DESCRIPTION("S3C2410/S3C2440 Timer Driver");
==========pwm_test.c====================
#include <stdio.h>
#include <termios.h>
#include <unistd.h>
#include <stdlib.h>
static int fd = -1;
int main(int argc, char **argv)
{
fd = open("/dev/pwm", 0);
if(fd<0)
{
printf("Open /dev/pwm failed!\n");
exit(1);
}
while( 1 );
close(fd);
}
==========timer_test.c====================
#include <stdio.h>
#include <termios.h>
#include <unistd.h>
#include <stdlib.h>
static int fd = -1;
int main(int argc, char **argv)
{
fd = open("/dev/timer", 0);
if(fd<0)
{
printf("Open /dev/timer failed!\n");
exit(1);
}
while( 1 );
close(fd);
}
==========drivers\char\Kconfig====================
加入
config MINI2440_TIMER
tristate "TIMER Driver Support for Mini2440"
depends on MACH_MINI2440
default y if MACH_MINI2440
help
This is Timer driver on Mini2440 boards.
==========drivers\char\Makefile====================
加入
obj-$(CONFIG_MINI2440_TIMER) += mini2440_timer.o
然後
make distclean
cp config_mini2440_t35 .config
make menuconfig
確認剛剛的timer driver有加入
存檔離開
make zImage
然後把編譯好的zImage下載到板子
在console底下
/home/plg/
執行 ./pwm_testing
可以看到
TEST_PWM_PRINTK
執行 ./timer_testing
卻甚麼都看不到......
為什麼呢??
