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想实现按键控制LED灯的功能
于是就在LED驱动例程上加以改动,通过原理图看到连接KEY1_UP的是GPH0(0),就用 S3C_GPIO_SFN(0)配置它为输入,但是发现返回总是0
就想把LED的GPC1(4)引脚配置为输入,看是否还能输出,结果都配置为0还是能让LED闪烁,这是为什么呢????????
是不是没有配置成功呢?需要怎么配置?
代码如下
/***********************************************************************************
* drivers/char/tq210_leds.c
* 功能简要:
* 该驱动注册一个字符设备“/dev/led”, 用于2个LED。
* 函数简介:
* static void tq210_debug_leds(unsigned int cmd,unsigned long arg),用于内核驱动调试
* 提供的外部接口:
* ioctol(struct inode *inode,struct file *file,unsigned int brightness);
* 用于LED的亮,灭。
* 调用实例:
* 提供控制台,命令式的测试程序。
*
*************************************************************************************/
#include <linux/miscdevice.h>
#include <linux/input.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <mach/map.h>
#include <mach/gpio.h>
//#include <mach/gpio-bank.h>
#include <mach/regs-gpio.h>
#include <plat/gpio-core.h>
#include <plat/gpio-cfg.h>
#include <plat/gpio-cfg-helpers.h>
#define DEVICE_NAME "led"
/* 应用程序执行ioctl(fd, cmd, arg)时的第2个参数 */
#define IOCTL_GPIO_ON 1
#define IOCTL_GPIO_OFF 0
/* 用来指定LED所用的GPIO引脚 */
static unsigned long gpio_table [] =
{
S5PV210_GPC1(3),
S5PV210_GPC1(4),
};
/* 用来指定GPIO引脚的功能:输入 */
static unsigned int gpio_cfg_table [] =
{
S3C_GPIO_SFN(0),
S3C_GPIO_SFN(0),
};
//static char gpio_name[][]={{"GPC1_3"},{"GPC1_4"}};
#ifdef CONFIG_TQ210_DEBUG_LEDS
static void tq210_debug_leds(unsigned int cmd,unsigned long arg)
{
gpio_direction_output(gpio_table[arg], cmd);
//s3c_gpio_setpin(gpio_table[arg], cmd);
}
static void toggle_led(unsigned int cmd,unsigned long arg)
{
int loop=0;
printk("%s : led %ld toggle now: \n",__func__,arg);
for(;loop<11;loop++)
{ cmd = loop%2;
printk("leds %d %s \n",arg+1,(cmd)?"on":"o ff");
tq210_debug_leds(cmd,arg);
mdelay(1000);
}
}
#endif
/**
*函数功能:打开/dev/led设备,设备名是:/dev/led
**/
static int tq210_gpio_open(struct inode *inode, struct file *file)
{
int i;
int err;
err = gpio_request(gpio_table[0], "GPC1_3");
if(err)
{
printk(KERN_ERR "failed to request GPC1_3 for LVDS PWDN pin\n");
return err;
}
err = gpio_request(gpio_table[1], "GPC1_4");
if(err)
{
printk(KERN_ERR "failed to request GPC1_4 for LVDS PWDN pin\n");
return err;
}
printk(KERN_INFO " leds opened\n");
for (i = 0; i < sizeof(gpio_table)/sizeof(unsigned long); i++)
{
s3c_gpio_cfgpin(gpio_table, gpio_cfg_table);
gpio_direction_output(gpio_table, 0);
//s3c_gpio_setpin(gpio_table, 0);
}
#ifdef CONFIG_TQ210_DEBUG_LEDS
for (i = 0; i < sizeof(gpio_table)/sizeof(unsigned long); i++)
{
toggle_led(1,i);
}
#endif
return 0;
}
/**
*函数功能:用于控制led的亮灭
*控制字为cmd,arg为控制哪个灯的亮灭取值范围为0-1:cmd为IOCTL_GPIO_ON时亮,cmd为IOCTL_GPIO_OFF为灭
**/
static long tq210_gpio_ioctl(
struct file *file,
unsigned int cmd,
unsigned long arg)
{
arg -= 1;
if (arg > sizeof(gpio_table)/sizeof(unsigned long))
{
return -EINVAL;
}
switch(cmd)
{
case IOCTL_GPIO_ON:
// 设置指定引脚的输出电平为1
gpio_direction_output(gpio_table[arg], 1);
//s3c_gpio_setpin(gpio_table[arg], 1);
return 0;
case IOCTL_GPIO_OFF:
// 设置指定引脚的输出电平为0
gpio_direction_output(gpio_table[arg], 0);
//s3c_gpio_setpin(gpio_table[arg], 0);
return 0;
default:
return -EINVAL;
}
}
static int tq210_gpio_close(struct inode *inode, struct file *file)
{
gpio_free(gpio_table[0]);
gpio_free(gpio_table[1]);
printk(KERN_INFO "TQ210 LEDs driver successfully close\n");
return 0;
}
/*驱动接口设置*/
static struct file_operations dev_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = tq210_gpio_ioctl,
.open = tq210_gpio_open,
.release = tq210_gpio_close,
};
/*设备结构的设置*/
static struct miscdevice misc = {
.minor = MISC_DYNAMIC_MINOR,
.name = DEVICE_NAME,
.fops = &dev_fops,
};
/*初始化设备,配置对应的IO,以及注册设备*/
static int __init dev_init(void)
{
int ret;
int i;
int err;
#ifdef CONFIG_TQ210_DEBUG_LEDS
err = gpio_request(gpio_table[0], "GPC1_3");
if(err)
{
printk(KERN_ERR "failed to request GPC1_3 for LVDS PWDN pin\n");
return err;
}
err = gpio_request(gpio_table[1], "GPC1_4");
if(err)
{
printk(KERN_ERR "failed to request GPC1_4 for LVDS PWDN pin\n");
return err;
}
for (i = 0; i < sizeof(gpio_table)/sizeof(unsigned long); i++)
{
//gpio_request(gpio_table[0],gpio_name);
s3c_gpio_cfgpin(gpio_table, gpio_cfg_table);//配置管脚为输出
gpio_direction_output(gpio_table, 0);
//s3c_gpio_setpin(gpio_table, 0);//设置管脚为低电平
s3c_gpio_setpull(gpio_table, S3C_GPIO_PULL_NONE);
}
#endif
ret = misc_register(&misc);
printk(KERN_INFO "TQ210 LEDs driver successfully probed\n");
#ifdef CONFIG_TQ210_DEBUG_LEDS
for (i = 0; i < sizeof(gpio_table)/sizeof(unsigned long); i++)
{
toggle_led(1,i);
}
#endif
return ret;
}
/*注销设备*/
static void __exit dev_exit(void)
{
misc_deregister(&misc);
gpio_free(gpio_table[0]);
gpio_free(gpio_table[1]);
printk(KERN_INFO "TQ210 LEDs driver successfully exit\n");
}
module_init(dev_init);
module_exit(dev_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul <shufexiu@163.com>");
MODULE_DESCRIPTION("LEDS' Driver");
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