1 简介
这篇文章是接着 《四 . 树莓派A20 GPIO中断程序编写(1基本处理)》 链接 来说的。
再上篇文章中,并没有谈到按键的消抖问题,导致再读取按键的时候,可能会出现连续读取了多个值的情况。
这篇文章主要添加了一个timer,也可以看作是推后一个时间来读取数据。这是基于这样的一个事实:
按键按下,初始过程中,会有抖动,这个时候,会频繁进入中断,那么中断程序中就频繁调用这个timer,从而一直修改读取时间,也就是不给应用层汇报值,一直到键值稳定,再去推后一个时间读取稳定的按键值。
2 基本的定时器消抖程序
首先按照sys_config.fex文件,如下所示:
然后是我们需要做的驱动程序key.c:
#include "linux/init.h"
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
/* EINT type PIO controller registers */
#define PIO_INT_CFG0_OFFSET 0x200
#define PIO_INT_CFG1_OFFSET 0x204
#define PIO_INT_CFG2_OFFSET 0x208
#define PIO_INT_CFG3_OFFSET 0x20c
#define PIO_INT_STAT_OFFSET (0x214)
#define PIO_INT_DATA_OFFSET (0x130)
#define IRQ_EINT22 22
#define IRQ_EINT23 23
#define PIO_BASE_ADDRESS SW_PA_PORTC_IO_BASE
#define PIO_RANGE_SIZE (0x400)
#define PIO_INT_CTRL_OFFSET (0x210)
/* EINT type defines */
#define POSITIVE_EDGE 0x0
#define NEGATIVE_EDGE 0x1
#define HIGH_LEVEL 0x2
#define LOW_LEVEL 0x3
#define DOUBLE_EDGE 0x4
static wait_queue_head_t key_data_avail;
static unsigned int key_done = 0;
static int int_cfg_addr[] = {PIO_INT_CFG0_OFFSET,
PIO_INT_CFG1_OFFSET,
PIO_INT_CFG2_OFFSET,
PIO_INT_CFG3_OFFSET};
/* Setup GPIO irq mode (FALLING, RISING, BOTH, etc */
#define SUNXI_SET_GPIO_IRQ_TYPE(addr, offs, mode) ({ \
__u32 reg_bit = offs % 8; \
__u32 reg_num = offs / 8; \
__u32 reg_val = readl(addr + int_cfg_addr[reg_num]); \
reg_val &= (~(0xf << (reg_bit * 4))); \
reg_val |= (mode << (reg_bit * 4)); \
writel(reg_val, addr + int_cfg_addr[reg_num]); \
})
/* Enable GPIO interrupt for pin */
#define SUNXI_UNMASK_GPIO_IRQ(addr, irq) ({ \
__u32 reg_val = readl(addr + PIO_INT_CTRL_OFFSET); \
reg_val |= (1 << irq); \
writel(reg_val, addr + PIO_INT_CTRL_OFFSET); \
})
/* Disable GPIO interrupt for pin */
#define SUNXI_MASK_GPIO_IRQ(addr, irq) ({ \
__u32 reg_val = readl(addr + PIO_INT_CTRL_OFFSET); \
reg_val &= ~(1 << irq); \
writel(reg_val, addr + PIO_INT_CTRL_OFFSET); \
})
/* Set GPIO pin mode (input, output, etc) */
/* GPIO port has 4 cfg 32bit registers (8 pins each) */
/* First port cfg register addr = port_num * 0x24 */
#define SUNXI_SET_GPIO_MODE(addr, port, pin, mode) ({ \
__u32 reg_val = 0; \
__u32 pin_idx = pin >> 3; \
void *raddr = addr + (((port)-1)*0x24 + ((pin_idx)<<2) + 0x00); \
reg_val = readl(raddr); \
reg_val &= ~(0x07 << (((pin - (pin_idx<<3))<<2))); \
reg_val |= mode << (((pin - (pin_idx<<3))<<2)); \
writel(reg_val, raddr); \
})
struct timer_list g_timer[2];
static script_gpio_set_t info;
static unsigned key_handler1;
static unsigned key_handler2;
static struct class *key_class;
static struct device *key_device;
static unsigned int key_major;
static unsigned int key_value;
static void *__iomem gpio_addr = NULL;
static int key_open(struct inode *inode, struct file *filp);
static ssize_t key_read (struct file *, char __user *, size_t, loff_t *);
static ssize_t key_write (struct file *filp, const char __user *buf, size_t len, loff_t *off);
static int key_close(struct inode *inode, struct file *filp);
struct file_operations key_operations = {
.owner = THIS_MODULE,
.open = key_open,
.read = key_read,
.write = key_write,
.release = key_close,
};
struct key_str{
char *name;
int val;
};
struct key_str g_key_str[2]={{"key1",0x1},{"key2",0x02}};
static irqreturn_t key_irq_handler1(int irq, void *dev_id)
{
int reg_val = 0;
//clear the IRQ_EINT22 interrupt pending
reg_val = readl(gpio_addr + PIO_INT_STAT_OFFSET);
if (reg_val & (1 << (IRQ_EINT22))) {
//printk("==IRQ_EINT22=\r\n");
writel(reg_val & (1 << (IRQ_EINT22)),
gpio_addr + PIO_INT_STAT_OFFSET);
mod_timer(&g_timer[0],jiffies + HZ/100);
}
return IRQ_HANDLED;
}
static irqreturn_t key_irq_handler2(int irq, void *dev_id)
{
int reg_val;
//clear the IRQ_EINT22 interrupt pending
reg_val = readl(gpio_addr + PIO_INT_STAT_OFFSET);
#if 1
if (reg_val & (1 << (IRQ_EINT23))) {
writel(reg_val & (1 << (IRQ_EINT23)),
gpio_addr + PIO_INT_STAT_OFFSET);
mod_timer(&g_timer[1],jiffies + HZ/100);
}
#endif
return IRQ_HANDLED;
}
void key_timer_function1(unsigned long data)
{
int ret_val;
ret_val = readl(gpio_addr + PIO_INT_DATA_OFFSET);
if(!(ret_val&(1<<10)))
{
//printk("key1 pressed \r\n");
key_value |= g_key_str[0].val;
}
else
{
//printk("key1 released \r\n");
key_value &= ~g_key_str[0].val;
}
key_done = 1;
wake_up_interruptible(&key_data_avail);
}
void key_timer_function2(unsigned long data)
{
int ret_val = 0;
ret_val = readl(gpio_addr + PIO_INT_DATA_OFFSET);
if(!(ret_val&(1<<11)))
{
//printk("key2 pressed \r\n");
key_value |= g_key_str[1].val;
}
else
{
//printk("key2 released \r\n");
key_value &= ~g_key_str[1].val;
}
key_done = 1;
wake_up_interruptible(&key_data_avail);
}
static ssize_t key_read (struct file *file, char __user *buf, size_t len, loff_t *off)
{
unsigned int value = 0;
key_done = 0;
wait_event_interruptible(key_data_avail,key_done);
value = copy_to_user(buf,&key_value,4);
return value;
}
static int key_open(struct inode *inode, struct file *filp)
{
int err = 0;
int key_test_enabled = 0;
err = script_parser_fetch("key_test_para", "key_test_enable", &key_test_enabled,
sizeof(key_test_enabled)/sizeof(int));
if(!err){
printk("---script.bin key get ok,value:%d----\n",key_test_enabled);
}
else
{
printk("---script.bin key get false----\n");
return -1;
}
err = script_parser_fetch("key_test_para", "key1",
(int *)&info,
sizeof(script_gpio_set_t));
if (err) {
printk("----script.bin get io error----\r\n");
return -1;
}
err = script_parser_fetch("key_test_para", "key2",
(int *)&info,
sizeof(script_gpio_set_t));
if (err) {
printk("----script.bin get io error----\r\n");
return -1;
}
/* reserve gpio for led */
key_handler1 = gpio_request_ex("key_test_para", "key1");
if (!key_handler1) {
printk("----script.bin can't requst handler----\r\n");
return -1;
}
/* reserve gpio for led */
key_handler2 = gpio_request_ex("key_test_para", "key2");
if (!key_handler2) {
printk("----script.bin can't requst handler----\r\n");
return -1;
}
#if 1
/*设置为输入,没有上下拉*/
err = gpio_set_one_pin_io_status(key_handler1,0,"key1");
if (err) {
printk("----set io input 1 error----\r\n");
return -1;
}
err = gpio_set_one_pin_io_status(key_handler2,0,"key2");
if (err) {
printk("----set io input 2 error----\r\n");
return -1;
}
#endif
err = gpio_set_one_pin_pull(key_handler1,1,"key1");
if (err) {
printk("----set io pull error----\r\n");
return -1;
}
err = gpio_set_one_pin_pull(key_handler2,1,"key2");
if (err) {
printk("----set io pull error----\r\n");
return -1;
}
if (!gpio_addr) {
gpio_addr = ioremap(PIO_BASE_ADDRESS, PIO_RANGE_SIZE);
}
if(!gpio_addr)
{
printk("-----address error-----\r\n");
}
err = request_irq(SW_INT_IRQNO_PIO, key_irq_handler1,
IRQF_SHARED, "gpio_pin_1", &g_key_str[0]);
if (err < 0) {
printk(" request irq 1 error:%d\n",err);
return -1;
}
err = request_irq(SW_INT_IRQNO_PIO, key_irq_handler2,
IRQF_SHARED, "gpio_pin_2", &g_key_str[1]);
if (err < 0) {
printk(" request irq error:%d\n",err);
return -1;
}
/*set the gpio 1 register*/
SUNXI_SET_GPIO_IRQ_TYPE(gpio_addr,IRQ_EINT22,DOUBLE_EDGE);
SUNXI_UNMASK_GPIO_IRQ(gpio_addr,IRQ_EINT22);
SUNXI_SET_GPIO_MODE(gpio_addr,9,10,6);/*PI10 EINT22 settiings*/
/*set the gpio 2 register*/
SUNXI_SET_GPIO_IRQ_TYPE(gpio_addr,IRQ_EINT23,DOUBLE_EDGE);
SUNXI_UNMASK_GPIO_IRQ(gpio_addr,IRQ_EINT23);
SUNXI_SET_GPIO_MODE(gpio_addr,9,11,6);/*PI11 EINT23 settiings*/
init_timer(&g_timer[0]);
g_timer[0].function = key_timer_function1;
g_timer[0].expires = jiffies + HZ / 100;
add_timer(&g_timer[0]);
init_timer(&g_timer[1]);
g_timer[1].function = key_timer_function2;
g_timer[1].expires = jiffies + HZ / 100;
add_timer(&g_timer[1]);
return 0;
}
static ssize_t key_write (struct file *filp, const char __user *buf, size_t len, loff_t *off)
{
return 0;
}
static int key_close(struct inode *inode, struct file *filp)
{
SUNXI_MASK_GPIO_IRQ(gpio_addr,IRQ_EINT22);
SUNXI_MASK_GPIO_IRQ(gpio_addr,IRQ_EINT23);
free_irq(SW_INT_IRQNO_PIO, &g_key_str[0]);
free_irq(SW_INT_IRQNO_PIO, &g_key_str[1]);
printk("----key close----\r\n");
return 0;
}
static int __init key_test_init(void)
{
key_major = register_chrdev(0, "key_chrdev", &key_operations);
key_class = class_create(THIS_MODULE, "key_class");
if(!key_class){
unregister_chrdev(key_major, "key_chrdev");
printk("----key_chrdev error----\r\n");
return -1;
}
key_device = device_create(key_class, NULL, MKDEV(key_major,0),
NULL, "key_device");
if(!key_device){
class_destroy(key_class);
unregister_chrdev(key_major, "key_chrdev");
printk("----key_device error----\r\n");
return -1;
}
printk("----key init ok----\r\n");
init_waitqueue_head(&key_data_avail);
return 0;
}
static void __exit key_test_exit(void)
{
del_timer(&g_timer[0]);
del_timer(&g_timer[1]);
if (gpio_addr) {
iounmap(gpio_addr);
}
if (key_handler1)
gpio_release(key_handler1, 1);
if (key_handler2)
gpio_release(key_handler2, 1);
device_destroy(key_class, MKDEV(key_major, 0));
class_destroy(key_class);
unregister_chrdev(key_major, "key_chrdev");
printk("---driver exit---\r\n");
}
module_init(key_test_init);
module_exit(key_test_exit);
MODULE_DESCRIPTION("Driver for key");
MODULE_AUTHOR("wit_yuan");
MODULE_LICENSE("GPL");
再就是测试程序,key_test.c:
#include "stdio.h"
#include
#include
#include
int main(int argc,char *argv[])
{
int fd;
int val;
fd = open("/dev/key_device",O_RDWR);
if(fd < 0){
printf("---open file error----\r\n");
return -1;
}
while(1)
{
read(fd,&val,1);
if(val!=0)
printf("val:%0x\r\n",val);
}
}
然后是Makefile文件:
ifeq ($(KERNELRELEASE),)
KERNEL_DIR=/home/wityuan/Downloads/MarsBoard-A20-Linux-SDK-V1.2/linux-sunxi
PWD=$(shell pwd)
modules:
$(MAKE) -C $(KERNEL_DIR) M=$(PWD) modules
arm-linux-gnueabihf-gcc -o key key.c
modules_install:
$(MAKE) -C $(KERNEL_DIR) M=$(PWD) modules_install
clean:
rm -rf *.ko *.o .tmp_versions *.mod.c modules.order Module.symvers .*.cmd
else
obj-m:=key.o
endif
最后是测试程序key_test.c:
#include "stdio.h"
#include
#include
#include
int main(int argc,char *argv[])
{
int fd;
int val;
fd = open("/dev/key_device",O_RDWR);
if(fd < 0){
printf("---open file error----\r\n");
return -1;
}
printf("---application run----\r\n");
while(1)
{
read(fd,&val,1);
if(val!=0)
printf("val:%0x\r\n",val);
}
return 0;
}
可实现的程序效果如下:
3 poll消抖程序
我们仍然写驱动程序,名称为key.c,如下:
#include "linux/init.h"
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
/* EINT type PIO controller registers */
#define PIO_INT_CFG0_OFFSET 0x200
#define PIO_INT_CFG1_OFFSET 0x204
#define PIO_INT_CFG2_OFFSET 0x208
#define PIO_INT_CFG3_OFFSET 0x20c
#define PIO_INT_STAT_OFFSET (0x214)
#define PIO_INT_DATA_OFFSET (0x130)
#define IRQ_EINT22 22
#define IRQ_EINT23 23
#define PIO_BASE_ADDRESS SW_PA_PORTC_IO_BASE
#define PIO_RANGE_SIZE (0x400)
#define PIO_INT_CTRL_OFFSET (0x210)
static DEFINE_SEMAPHORE(key_lock);
/* EINT type defines */
#define POSITIVE_EDGE 0x0
#define NEGATIVE_EDGE 0x1
#define HIGH_LEVEL 0x2
#define LOW_LEVEL 0x3
#define DOUBLE_EDGE 0x4
static wait_queue_head_t key_wait_q;
static int int_cfg_addr[] = {PIO_INT_CFG0_OFFSET,
PIO_INT_CFG1_OFFSET,
PIO_INT_CFG2_OFFSET,
PIO_INT_CFG3_OFFSET};
/* Setup GPIO irq mode (FALLING, RISING, BOTH, etc */
#define SUNXI_SET_GPIO_IRQ_TYPE(addr, offs, mode) ({ \
__u32 reg_bit = offs % 8; \
__u32 reg_num = offs / 8; \
__u32 reg_val = readl(addr + int_cfg_addr[reg_num]); \
reg_val &= (~(0xf << (reg_bit * 4))); \
reg_val |= (mode << (reg_bit * 4)); \
writel(reg_val, addr + int_cfg_addr[reg_num]); \
})
/* Enable GPIO interrupt for pin */
#define SUNXI_UNMASK_GPIO_IRQ(addr, irq) ({ \
__u32 reg_val = readl(addr + PIO_INT_CTRL_OFFSET); \
reg_val |= (1 << irq); \
writel(reg_val, addr + PIO_INT_CTRL_OFFSET); \
})
/* Disable GPIO interrupt for pin */
#define SUNXI_MASK_GPIO_IRQ(addr, irq) ({ \
__u32 reg_val = readl(addr + PIO_INT_CTRL_OFFSET); \
reg_val &= ~(1 << irq); \
writel(reg_val, addr + PIO_INT_CTRL_OFFSET); \
})
/* Set GPIO pin mode (input, output, etc) */
/* GPIO port has 4 cfg 32bit registers (8 pins each) */
/* First port cfg register addr = port_num * 0x24 */
#define SUNXI_SET_GPIO_MODE(addr, port, pin, mode) ({ \
__u32 reg_val = 0; \
__u32 pin_idx = pin >> 3; \
void *raddr = addr + (((port)-1)*0x24 + ((pin_idx)<<2) + 0x00); \
reg_val = readl(raddr); \
reg_val &= ~(0x07 << (((pin - (pin_idx<<3))<<2))); \
reg_val |= mode << (((pin - (pin_idx<<3))<<2)); \
writel(reg_val, raddr); \
})
struct timer_list g_timer[2];
static script_gpio_set_t info;
static unsigned key_handler1;
static unsigned key_handler2;
static struct class *key_class;
static struct device *key_device;
static unsigned int key_major;
static unsigned int key_value;
static void *__iomem gpio_addr = NULL;
static int key_press = 0;
static int key_open(struct inode *inode, struct file *filp);
static ssize_t key_read (struct file *, char __user *, size_t, loff_t *);
static ssize_t key_write (struct file *filp, const char __user *buf, size_t len, loff_t *off);
static int key_close(struct inode *inode, struct file *filp);
static unsigned int key_poll(struct file *, struct poll_table_struct *);
struct file_operations key_operations = {
.owner = THIS_MODULE,
.open = key_open,
.read = key_read,
.write = key_write,
.release = key_close,
.poll = key_poll,
};
struct key_str{
char *name;
int val;
};
struct key_str g_key_str[2]={{"key1",0x1},{"key2",0x02}};
static irqreturn_t key_irq_handler1(int irq, void *dev_id)
{
int reg_val = 0;
//clear the IRQ_EINT22 interrupt pending
reg_val = readl(gpio_addr + PIO_INT_STAT_OFFSET);
if (reg_val & (1 << (IRQ_EINT22))) {
//printk("==IRQ_EINT22=\r\n");
writel(reg_val & (1 << (IRQ_EINT22)),
gpio_addr + PIO_INT_STAT_OFFSET);
mod_timer(&g_timer[0],jiffies + HZ/100);
}
return IRQ_HANDLED;
}
static irqreturn_t key_irq_handler2(int irq, void *dev_id)
{
int reg_val;
//clear the IRQ_EINT22 interrupt pending
reg_val = readl(gpio_addr + PIO_INT_STAT_OFFSET);
#if 1
if (reg_val & (1 << (IRQ_EINT23))) {
writel(reg_val & (1 << (IRQ_EINT23)),
gpio_addr + PIO_INT_STAT_OFFSET);
mod_timer(&g_timer[1],jiffies + HZ/100);
}
#endif
return IRQ_HANDLED;
}
void key_timer_function1(unsigned long data)
{
int ret_val;
ret_val = readl(gpio_addr + PIO_INT_DATA_OFFSET);
if(!(ret_val&(1<<10)))
{
//printk("key1 pressed \r\n");
key_value |= g_key_str[0].val;
}
else
{
//printk("key1 released \r\n");
key_value &= ~g_key_str[0].val;
}
key_press = 1;
wake_up_interruptible(&key_wait_q);
}
void key_timer_function2(unsigned long data)
{
int ret_val = 0;
ret_val = readl(gpio_addr + PIO_INT_DATA_OFFSET);
if(!(ret_val&(1<<11)))
{
//printk("key2 pressed \r\n");
key_value |= g_key_str[1].val;
}
else
{
//printk("key2 released \r\n");
key_value &= ~g_key_str[1].val;
}
key_press = 1;
wake_up_interruptible(&key_wait_q);
}
static unsigned int key_poll(struct file *filep, struct poll_table_struct *wait)
{
unsigned int mask = 0;
poll_wait(filep,&key_wait_q,wait);
if(key_press){
mask |= POLLIN | POLLRDNORM;
}
return mask;
}
static ssize_t key_read (struct file *filep, char __user *buf, size_t len, loff_t *off)
{
unsigned int value = 0;
if(len != 4)
return -EINVAL;
if(filep->f_flags & O_NONBLOCK){
if(!key_press){
return -EAGAIN;
}
}
else
{
wait_event_interruptible(key_wait_q,key_press);
}
key_press = 0;
value = copy_to_user(buf,&key_value,4);
return value;
}
static int key_open(struct inode *inode, struct file *filep)
{
int err = 0;
int key_test_enabled = 0;
if(filep->f_flags & O_NONBLOCK){
if(down_trylock(&key_lock)){
return -EBUSY;
}
}
else
{
down(&key_lock);
}
err = script_parser_fetch("key_test_para", "key_test_enable", &key_test_enabled,
sizeof(key_test_enabled)/sizeof(int));
if(!err){
printk("---script.bin key get ok,value:%d----\n",key_test_enabled);
}
else
{
printk("---script.bin key get false----\n");
return -1;
}
err = script_parser_fetch("key_test_para", "key1",
(int *)&info,
sizeof(script_gpio_set_t));
if (err) {
printk("----script.bin get io error----\r\n");
return -1;
}
err = script_parser_fetch("key_test_para", "key2",
(int *)&info,
sizeof(script_gpio_set_t));
if (err) {
printk("----script.bin get io error----\r\n");
return -1;
}
/* reserve gpio for led */
key_handler1 = gpio_request_ex("key_test_para", "key1");
if (!key_handler1) {
printk("----script.bin can't requst handler----\r\n");
return -1;
}
/* reserve gpio for led */
key_handler2 = gpio_request_ex("key_test_para", "key2");
if (!key_handler2) {
printk("----script.bin can't requst handler----\r\n");
return -1;
}
#if 1
/*设置为输入,没有上下拉*/
err = gpio_set_one_pin_io_status(key_handler1,0,"key1");
if (err) {
printk("----set io input 1 error----\r\n");
return -1;
}
err = gpio_set_one_pin_io_status(key_handler2,0,"key2");
if (err) {
printk("----set io input 2 error----\r\n");
return -1;
}
#endif
err = gpio_set_one_pin_pull(key_handler1,1,"key1");
if (err) {
printk("----set io pull error----\r\n");
return -1;
}
err = gpio_set_one_pin_pull(key_handler2,1,"key2");
if (err) {
printk("----set io pull error----\r\n");
return -1;
}
if (!gpio_addr) {
gpio_addr = ioremap(PIO_BASE_ADDRESS, PIO_RANGE_SIZE);
}
if(!gpio_addr)
{
printk("-----address error-----\r\n");
}
err = request_irq(SW_INT_IRQNO_PIO, key_irq_handler1,
IRQF_SHARED, "gpio_pin_1", &g_key_str[0]);
if (err < 0) {
printk(" request irq 1 error:%d\n",err);
return -1;
}
err = request_irq(SW_INT_IRQNO_PIO, key_irq_handler2,
IRQF_SHARED, "gpio_pin_2", &g_key_str[1]);
if (err < 0) {
printk(" request irq error:%d\n",err);
return -1;
}
/*set the gpio 1 register*/
SUNXI_SET_GPIO_IRQ_TYPE(gpio_addr,IRQ_EINT22,DOUBLE_EDGE);
SUNXI_UNMASK_GPIO_IRQ(gpio_addr,IRQ_EINT22);
SUNXI_SET_GPIO_MODE(gpio_addr,9,10,6);/*PI10 EINT22 settiings*/
/*set the gpio 2 register*/
SUNXI_SET_GPIO_IRQ_TYPE(gpio_addr,IRQ_EINT23,DOUBLE_EDGE);
SUNXI_UNMASK_GPIO_IRQ(gpio_addr,IRQ_EINT23);
SUNXI_SET_GPIO_MODE(gpio_addr,9,11,6);/*PI11 EINT23 settiings*/
init_timer(&g_timer[0]);
g_timer[0].function = key_timer_function1;
g_timer[0].expires = jiffies + HZ / 100;
add_timer(&g_timer[0]);
init_timer(&g_timer[1]);
g_timer[1].function = key_timer_function2;
g_timer[1].expires = jiffies + HZ / 100;
add_timer(&g_timer[1]);
return 0;
}
static ssize_t key_write (struct file *filp, const char __user *buf, size_t len, loff_t *off)
{
return 0;
}
static int key_close(struct inode *inode, struct file *filp)
{
SUNXI_MASK_GPIO_IRQ(gpio_addr,IRQ_EINT22);
SUNXI_MASK_GPIO_IRQ(gpio_addr,IRQ_EINT23);
free_irq(SW_INT_IRQNO_PIO, &g_key_str[0]);
free_irq(SW_INT_IRQNO_PIO, &g_key_str[1]);
printk("----key close----\r\n");
return 0;
}
static int __init key_test_init(void)
{
key_major = register_chrdev(0, "key_chrdev", &key_operations);
key_class = class_create(THIS_MODULE, "key_class");
if(!key_class){
unregister_chrdev(key_major, "key_chrdev");
printk("----key_chrdev error----\r\n");
return -1;
}
key_device = device_create(key_class, NULL, MKDEV(key_major,0),
NULL, "key_device");
if(!key_device){
class_destroy(key_class);
unregister_chrdev(key_major, "key_chrdev");
printk("----key_device error----\r\n");
return -1;
}
printk("----key init ok----\r\n");
init_waitqueue_head(&key_wait_q);
return 0;
}
static void __exit key_test_exit(void)
{
del_timer(&g_timer[0]);
del_timer(&g_timer[1]);
if (gpio_addr) {
iounmap(gpio_addr);
}
if (key_handler1)
gpio_release(key_handler1, 1);
if (key_handler2)
gpio_release(key_handler2, 1);
device_destroy(key_class, MKDEV(key_major, 0));
class_destroy(key_class);
unregister_chrdev(key_major, "key_chrdev");
printk("---driver exit---\r\n");
}
module_init(key_test_init);
module_exit(key_test_exit);
MODULE_DESCRIPTION("Driver for key");
MODULE_AUTHOR("wit_yuan");
MODULE_LICENSE("GPL");
再就是Makefile文件:
ifeq ($(KERNELRELEASE),)
KERNEL_DIR=/home/wityuan/Downloads/MarsBoard-A20-Linux-SDK-V1.2/linux-sunxi
PWD=$(shell pwd)
modules:
$(MAKE) -C $(KERNEL_DIR) M=$(PWD) modules
arm-linux-gnueabihf-gcc -o key key.c
modules_install:
$(MAKE) -C $(KERNEL_DIR) M=$(PWD) modules_install
clean:
rm -rf *.ko *.o .tmp_versions *.mod.c modules.order Module.symvers .*.cmd
else
obj-m:=key.o
endif
最后是应用层程序key_test.c:
#include "stdio.h"
#include
#include
#include
#include
int main(int argc,char *argv[])
{
int fd;
int val;
int ret;
struct pollfd fds[1];
fd = open("/dev/key_device",O_RDWR);
if(fd < 0){
printf("---open file error----\r\n");
return -1;
}
printf("---application run----\r\n");
fds[0].fd = fd;
fds[0].events = POLLIN;
while(1)
{
ret = poll(fds,1,5000);
if(ret == 0){
printf("---time out---\r\n");
}
else
{
read(fd,&val,4);
if(val!=0)
printf("val:%0x\r\n",val);
}
}
return 0;
}
最终驱动程序效果如下图所示: