qt2410-buttons.c

来自「这份源码是用基于QT2410的嵌入式Linux开发的按键驱动程序以及测试程序.」· C语言 代码 · 共 85 行

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>

#include <linux/miscdevice.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/poll.h>
#include <linux/spinlock.h>
#include <linux/irq.h>
#include <linux/delay.h>

#include <asm/hardware.h>

#define DEVICE_NAME	"qt2410_btns"
#define BUTTON_MAJOR 232
#define IRQ_BUTTONS IRQ_EINT7


//static int count = 0;

//static int ready = 0;
static int key_value = 0;

static DECLARE_WAIT_QUEUE_HEAD(buttons_wait);

static void buttons_io_port_init(void)
{
	set_gpio_ctrl(GPIO_F0 | GPIO_PULLUP_DIS | GPIO_MODE_IN);//added
	set_gpio_ctrl(GPIO_F2 | GPIO_PULLUP_DIS | GPIO_MODE_IN);//added
}

static int qt2410_buttons_read(struct file * file, char * buffer, size_t count, loff_t *ppos)
{
        if (count != sizeof key_value)
                return -EINVAL;

	key_value = GPFDAT;//added

        copy_to_user(buffer, &key_value, sizeof key_value);
        return sizeof key_value;
}

static int qt2410_buttons_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
	switch(cmd) {
	default:
		return -EINVAL;
	}
}
static struct file_operations qt2410_buttons_fops = {
	owner:	THIS_MODULE,
	ioctl:  qt2410_buttons_ioctl,
//	poll: qt2410_buttons_select,
	read: qt2410_buttons_read,
};

static devfs_handle_t devfs_handle;
static int __init qt2410_buttons_init(void)
{
	int ret;
	ret = register_chrdev(BUTTON_MAJOR, DEVICE_NAME, &qt2410_buttons_fops);
	if (ret < 0) {
	  printk(DEVICE_NAME " can't register major number\n");
	  return ret;
	}
	buttons_io_port_init();
	devfs_handle = devfs_register(NULL, DEVICE_NAME, DEVFS_FL_DEFAULT,
				BUTTON_MAJOR, 0, S_IFCHR | S_IRUSR | S_IWUSR, &qt2410_buttons_fops, NULL);

	return 0;
}

static void __exit qt2410_buttons_exit(void)
{
	devfs_unregister(devfs_handle);
	unregister_chrdev(BUTTON_MAJOR, DEVICE_NAME);
}

module_init(qt2410_buttons_init);
module_exit(qt2410_buttons_exit);
MODULE_LICENSE("GPL");