1.定時器：
1).超時時間
2).處理函式
#include #include#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
static
struct
class *sixthdrv_class;
static
struct class_device *sixthdrv_class_dev;
volatile unsigned long *gpfcon;
volatile unsigned long *gpfdat;
volatile unsigned long *gpgcon;
volatile unsigned long *gpgdat;
//定時器
static struct timer_list buttons_timer;
static
declare_wait_queue_head(button_waitq);
/*中斷事件標誌, 中斷服務程式將它置1，sixth_drv_read將它清0
*/static
volatile
int ev_press = 0
;static
struct fasync_struct *button_async;
struct
pin_desc;
/*鍵值: 按下時, 0x01, 0x02, 0x03, 0x04
*//*
鍵值: 鬆開時, 0x81, 0x82, 0x83, 0x84
*/static unsigned char
key_val;
struct pin_desc pins_desc[4] =,,,
,};static
struct pin_desc *irq_pd;
//static atomic_t canopen = atomic_init(1);
//定義原子變數並初始化為1
static declare_mutex(button_lock); //
定義互斥鎖
/** 確定按鍵值
*/static irqreturn_t buttons_irq(int irq, void *dev_id)
static
int sixth_drv_open(struct inode *inode, struct file *file)
#endif
if (file->f_flags &o_nonblock)
else
/*配置gpf0,2為輸入引腳
*//*
配置gpg3,11為輸入引腳
*/request_irq(irq_eint0, buttons_irq, irqt_bothedge, "s2
", &pins_desc[0
]); request_irq(irq_eint2, buttons_irq, irqt_bothedge, "s3
", &pins_desc[1
]); request_irq(irq_eint11, buttons_irq, irqt_bothedge, "s4
", &pins_desc[2
]); request_irq(irq_eint19, buttons_irq, irqt_bothedge, "s5
", &pins_desc[3
]);
return0;
}ssize_t sixth_drv_read(
struct file *file, char __user *buf, size_t size, loff_t *ppos)
else
/*如果有按鍵動作, 返回鍵值
*/copy_to_user(buf, &key_val, 1
); ev_press = 0
;
return1;
}int sixth_drv_close(struct inode *inode, struct file *file)
static unsigned sixth_drv_poll(struct file *file, poll_table *wait)
static
int sixth_drv_fasync (int fd, struct file *filp, int
on)static
struct file_operations sencod_drv_fops =;
intmajor;
static
void buttons_timer_function(unsigned long
data)
else
ev_press = 1; /*
表示中斷發生了
*/wake_up_interruptible(&button_waitq); /*
喚醒休眠的程序
*/kill_fasync (&button_async, sigio, poll_in);
}static
int sixth_drv_init(void
)static
void sixth_drv_exit(void
)module_init(sixth_drv_init);
module_exit(sixth_drv_exit);
module_license(
"gpl
");
2.測試程式
#include #include#include
#include
#include
#include
#include
#include
#include
/*sixthdrvtest
*/intfd;
void my_signal_fun(int
signum)
int main(int argc, char **argv)
//fcntl(fd, f_setown, getpid());
//oflags = fcntl(fd, f_getfl);
//fcntl(fd, f_setfl, oflags | fasync);
while (1
)
return0;
}
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