buttons.c
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
static int major = 0;
static struct class *cls;
/* gpecon 0x56000040 */
/* gpfcon 0x56000050 */
/* gpgcon 0x56000060 */
static volatile unsigned long *gpecon;
static volatile unsigned long *gpedat;
static volatile unsigned long *gpfcon;
static volatile unsigned long *gpfdat;
static volatile unsigned long *gpgcon;
static volatile unsigned long *gpgdat;
struct key_desc ;
struct key_desc key_desc = , /* 鬆開: 1, 按下: 0x81 */
, /* 鬆開: 2, 按下: 0x82 */
, /* 鬆開: 3, 按下: 0x83 */
, /* 鬆開: 4, 按下: 0x84 */
};volatile char key = 0;
static wait_queue_head_t button_waitq;
#define buf_len 10
static char key_buf[buf_len];
static volatile int r = 0, w = 0;
static intisempty(void)
static intisfull(void)
static intputdata(char val)
else
}static intgetdata(char *p)
else
}static irqreturn_t buttons_irq(int irq, void *dev_id)
else
// printk("key = 0x%x\n", key);
putdata(key);
/* 喚醒應用程式 */
wake_up_interruptible(&button_waitq);
//printk("buttons_irq current %s , pid = %d \n", current->comm, current->pid);
return irq_handled;
}int buttons_open(struct inode *inode, struct file *file)
/* 設定gpio為中斷引腳
* 設定觸發方式
* 使能中斷
*//* 設定kscan0(gpe11)為輸出引腳,輸出0 */
*gpecon &= ~(0x3 << 22);
*gpecon |= (1 << 22);
*gpedat &= ~(1<<11);
return 0;
}ssize_t buttons_read(struct file *inode, char __user *buf, size_t size, loff_t *offset)
int buttons_close(struct inode *inode, struct file *file)
return 0;
}static const struct file_operations buttons_fops = ;
int buttons_init(void)
void buttons_exit(void)
module_init(buttons_init);
module_exit(buttons_exit);
module_license("gpl");
buttons_test.c
#include
#include
#include
#include
#include
int main(int argc, char **argv)
while (1)
return 0;
}
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