友善之臂的Tiny210 linux3.0.8 for android
实现：在linux内核下添加LED的驱动 LED@LZM@FJICC并且可以在# /dev/下看到。
#ls /dev/ 看到驱动LED@LZM@FJICC
1.进入linux/drivers/char/新建一个文件lzm_fjicc.c
编写内容：
//lzm_fjicc.c
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/delay.h>
#include <mach/gpio.h>
#include <mach/regs-gpio.h>
#include <plat/gpio-cfg.h>
#define DEVICE_NAME "LED@LZM@FJICC"
static int led_gpios[] = {
S5PV210_GPJ2(0),
S5PV210_GPJ2(1),
S5PV210_GPJ2(2),
S5PV210_GPJ2(3),
};
#define LED_NUMARRAY_SIZE(led_gpios)
static long fjicc_leds_ioctl(struct file *filp, unsigned int cmd,
unsigned long arg)
{
switch(cmd) {
case 0:
case 1:
if (arg > LED_NUM) {
return -EINVAL;
}
gpio_set_value(led_gpios[arg], !cmd);
//printk(DEVICE_NAME": %d %d\n", arg, cmd);
break;
default:
return -EINVAL;
}
return 0;
}
static struct file_operations fjicc_led_dev_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = fjicc_leds_ioctl,
};
static struct miscdevice fjicc_led_dev = {
.minor = MISC_DYNAMIC_MINOR,
.name = DEVICE_NAME,
.fops = &fjicc_led_dev_fops,
};
static int __init fjicc_led_dev_init(void) {
int ret;
int i;
for (i = 0; i < LED_NUM; i++) {
ret = gpio_request(led_gpios[i], "LED");
if (ret) {
printk("%s: request GPIO %d for LED failed, ret = %d\n", DEVICE_NAME,
led_gpios[i], ret);
return ret;
}
s3c_gpio_cfgpin(led_gpios[i], S3C_GPIO_OUTPUT);
gpio_set_value(led_gpios[i], 1);
}
ret = misc_register(&fjicc_led_dev);
printk(DEVICE_NAME"\tinitialized\n");
return ret;
}
static void __exit fjicc_led_dev_exit(void) {
int i;
for (i = 0; i < LED_NUM; i++) {
gpio_free(led_gpios[i]);
}
misc_deregister(&fjicc_led_dev);
}
module_init(fjicc_led_dev_init);
module_exit(fjicc_led_dev_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("LZM@FJICC");
2.然后修改char目录下的Kconfig和Makefile文件：
Kconfig:
config LEDS_LZM_FJICC
tristate "LEDS_LZM_FJICC"
depends on MACH_MINI210
default y
help
This option enables support for LEDs connected to GPIO lines
on Mini210 boards.
Makefile:
obj-$(CONFIG_LEDS_LZM_FJICC) += lzm_fjicc.o
3.进到linux根目录，然后#make menuconfig
就可以在配置菜单中看到LEDS_LZM_FJICC,具体在devices driversàchracter devicesà就可以看到了。
4.配置好了，make zImage就可以了。
5.烧写了系统后，就可以查看驱动了。#ls /dev/
6.提升驱动权限：#chmod 777 /dev/LED@LZM@FJICC