OpenWrt添加驱动模块

1. 添加模块目录

在package/kernel/下执行命令：
mkdir example

2. 建立Makefile

在package/kernel/example建立Makefile文件，命令：vim Makefile，内容如下：

#Kernel module example

include $(TOPDIR)/rules.mk
include $(INCLUDE_DIR)/kernel.mk

PKG_NAME:=example
PKG_RELEASE:=1

include $(INCLUDE_DIR)/package.mk

define KernelPackage/example
  SUBMENU:=Other modules
  TITLE:=Support Module for example
  FILES:=$(PKG_BUILD_DIR)/$(PKG_NAME).ko
  AUTOLOAD:=$(call AutoLoad,81,$(PKG_NAME))
endef

EXTRA_KCONFIG:= \
    CONFIG_$(PKG_NAME)=m

EXTRA_CFLAGS:= \
    $(patsubst CONFIG_%, -DCONFIG_%=1, $(patsubst %=m,%,$(filter %=m,$(EXTRA_KCONFIG)))) \
    $(patsubst CONFIG_%, -DCONFIG_%=1, $(patsubst %=y,%,$(filter %=y,$(EXTRA_KCONFIG)))) \

MAKE_OPTS:= \
    ARCH="$(LINUX_KARCH)" \
    CROSS_COMPILE="$(TARGET_CROSS)" \
    SUBDIRS="$(PKG_BUILD_DIR)" \
    EXTRA_CFLAGS="$(EXTRA_CFLAGS)" \
    $(EXTRA_KCONFIG)

define Build/Compile
    $(MAKE) -C "$(LINUX_DIR)" \
        $(MAKE_OPTS) \
        modules
endef

$(eval $(call KernelPackage,$(PKG_NAME)))

3. 建立src目录

在package/kernel/example下建立src目录，命令：mkdir src，在src目录下建立Kconfig、Makefile和example.c文件。

3.1 Kconfig文件内容

config EXAMPLE
    tristate "Just a example"
    help
    This is a example, for debugging kernel model.
    If unsure, say N.

3.2 Makefile文件内容

obj-${CONFIG_EXAMPLE}  += example.o

3.3 example.c文件内容

#include 
#include 
#include 

static int __init example_init(void)
{
    printk("hello example lede init!\n");
    return 0;
}

static void __exit example_exit(void)
{
    printk("hello example lede exit!\n");
}

module_init(example_init);
module_exit(example_exit);

MODULE_AUTHOR("hello world");
MODULE_DESCRIPTION("example driver");
MODULE_LICENSE("GPL");

4. 配置make menuconfig

在openwrt目录make menuconfig–>kernel module–>other module–>kmod-example选中，执行编译命令：make package/kernel/example/compile V=s