驱动的移植。
在drivers/char 目录下，我们建立一个驱动程序文件mini2440_leds.c，内容如下:
<span style="font-size: 18px;">#include <linux/miscdevice.h>
#include <linux/delay.h>
#include <asm/irq.h>
#include <mach/regs-gpio.h>
#include <mach/hardware.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/gpio.h>
#include <asm/uaccess.h>
#include <asm/atomic.h>
#include <asm/unistd.h>
#define DEVICE_NAME "leds" <span style="color: rgb(51, 102, 255);">//设备名(/dev/leds</span>)
<span style="color: rgb(51, 102, 255);">//LED 对应的GPIO 端口列表
</span>static unsigned long led_table [] = {
S3C2410_GPB(5),
S3C2410_GPB(6),
S3C2410_GPB(7),
S3C2410_GPB(8),
};
<span style="color: rgb(51, 102, 255);">//LED 对应端口将要输出的状态列表
</span>static unsigned int led_cfg_table [] = {
S3C2410_GPIO_OUTPUT,
S3C2410_GPIO_OUTPUT,
S3C2410_GPIO_OUTPUT,
S3C2410_GPIO_OUTPUT,
};
<span style="color: rgb(51, 102, 255);">/*ioctl 函数的实现
* 在应用/用户层将通过ioctl 函数向内核传递参数，以控制LED 的输出状态
*/
</span>static int sbc2440_leds_ioctl(
struct inode *inode,
struct file *file,
unsigned int cmd,
unsigned long arg)
{
switch(cmd) {
case 0:
case 1:
if (arg > 4) {
return -EINVAL;
}
<span style="color: rgb(51, 102, 255);">//根据应用/用户层传递来的参数(取反)，通过s3c2410_gpio_setpin 函数设置LED 对应的端口寄存
器，</span>
s3c2410_gpio_setpin(led_table[arg], !cmd);
return 0;
default:
return -EINVAL;
}
}
<span style="color: rgb(51, 102, 255);">/*
* 设备函数操作集，在此只有ioctl 函数，通常还有read, write, open, close 等，因为本LED 驱动在下面已经
* 注册为misc 设备，因此也可以不用open/close
*/
</span>static struct file_operations dev_fops = {
.owner = THIS_MODULE,
.ioctl = sbc2440_leds_ioctl,
};
<span style="color: rgb(51, 102, 255); ">/*
* 把LED 驱动注册为MISC 设备
*/
</span>static struct miscdevice misc = {
.minor = MISC_DYNAMIC_MINOR, //动态设备号
.name = DEVICE_NAME,
.fops = &dev_fops,
};
<span style="color: rgb(51, 102, 255);">/*
* 设备初始化
*/
</span>static int __init dev_init(void)
{
int ret;
int i;
for (i = 0; i < 4; i++) {
<span style="color: rgb(51, 102, 255);">//设置LED 对应的端口寄存器为输出(OUTPUT)
</span>s3c2410_gpio_cfgpin(led_table[i], led_cfg_table[i]);
<span style="color: rgb(51, 102, 255);">//设置LED 对应的端口寄存器为低电平输出，在模块加载结束后，四个LED 应该是全部都是发光
状态</span>
s3c2410_gpio_setpin(led_table[i], 0);
}
ret = misc_register(&misc); <span style="color: rgb(51, 102, 255);">//注册设备</span>
printk (DEVICE_NAME"\tinitialized\n"); <span style="color: rgb(51, 102, 255);">//打印初始化信息</span>
return ret;
}
static void __exit dev_exit(void)
{
misc_deregister(&misc);
}
module_init(dev_init); <span style="color: rgb(51, 51, 255);">//模块初始化，仅当使用insmod/podprobe 命令加载时有用，如果设备不是通过模块方式加载，此处将不会被调用
</span>module_exit(dev_exit<span style="">);<span style="color: rgb(51, 102, 255);">//卸载模块，当该设备通过模块方式加载后，可以通过rmmod 命令卸载，将调用此函
</span></span><span style="">数
</span>MODULE_LICENSE("GPL"); <span style="color: rgb(51, 102, 255);">//版权信息
</span>MODULE_AUTHOR("FriendlyARM Inc."); <span style="color: rgb(51, 102, 255); ">//开发者信息</span></span>
接下来，我们添加LED 设备的内核配置选项，打开drivers/char/Kconfig 文件，添加如下红色部分内容：
config DEVKMEM
bool "/dev/kmem virtual device support"
default y
help
Say Y here if you want to support the /dev/kmem device. The
/dev/kmem device is rarely used, but can be used for certain
kind of kernel debugging operations.
When in doubt, say "N".
config LEDS_MINI2440
tristate "LED Support for Mini2440 GPIO LEDs"
depends on MACH_MINI2440
default y if MACH_MINI2440
help
This option enables support for LEDs connected to GPIO lines
on Mini2440 boards.
config MINI2440_ADC
bool "ADC driver for FriendlyARM Mini2440 development boards"
depends on MACH_MINI2440
default y if MACH_MINI2440
help
this is ADC driver for FriendlyARM Mini2440 development boards
Notes: the touch-screen-driver required this option
接下来，再根据该驱动的配置定义，把对应的驱动目标文件加入内核中，打开linux-2.6.32.2/drivers/char/Makefile 文件，添加如下红色部分内容：
obj-$(CONFIG_JS_RTC) += js-rtc.o
js-rtc-y = rtc.o
obj-$(CONFIG_LEDS_MINI2440) += mini2440_leds.o
obj-$(CONFIG_MINI2440_ADC) += mini2440_adc.o
# Files generated that shall be removed upon make clean
clean-files := consolemap_deftbl.c defkeymap.c
这样，我们就在内核中添加做好了LED 驱动。
http://www.cnblogs.com/z378560707/