查看驱动目录下的makefile
可以看到很多配置项
linux\drivers\char\Makefile:
obj-$(CONFIG_DTLK) += dtlk.oobj-$(CONFIG_APPLICOM) += applicom.oobj-$(CONFIG_SONYPI) += sonypi.oobj-$(CONFIG_RTC) += rtc.oobj-$(CONFIG_HPET) += hpet.oobj-$(CONFIG_EFI_RTC) += efirtc.oobj-$(CONFIG_XILINX_HWICAP) += xilinx_hwicap/ifeq ($(CONFIG_GENERIC_NVRAM),y) obj-$(CONFIG_NVRAM) += generic_nvram.oelse obj-$(CONFIG_NVRAM) += nvram.oendifobj-$(CONFIG_TOSHIBA) += toshiba.oobj-$(CONFIG_DS1620) += ds1620.oobj-$(CONFIG_HW_RANDOM) += hw_random/obj-$(CONFIG_PPDEV) += ppdev.oobj-$(CONFIG_NWBUTTON) += nwbutton.oobj-$(CONFIG_NWFLASH) += nwflash.oobj-$(CONFIG_SCx200_GPIO) += scx200_gpio.oobj-$(CONFIG_PC8736x_GPIO) += pc8736x_gpio.oobj-$(CONFIG_NSC_GPIO) += nsc_gpio.oobj-$(CONFIG_GPIO_TB0219) += tb0219.oobj-$(CONFIG_TELCLOCK) += tlclk.o
比如obj-$(CONFIG_DS1620) += ds1620.o
- 当CONFIG_DS1620为y ： obj-y += ds1620.o 表示把该驱动编译进内核
- 当CONFIG_DS1620为m ： obj-m += ds1620.o 表示把该驱动编译成模块
- 当CONFIG_DS1620为m ： obj-n += ds1620.o 不编译该驱动
1、CONFIG_DS1620配置选项怎么来：
内核根目录.config
2、内核根目录.config如何生成?
通过默认配置文件配置内核得到.config：
make imx_v7_defconfig
arch\arm\configs\imx_v7_defconfig
配置内核会将imx_v7_defconfig的内容复制为.config
3、修改.config
make menuconfig //图形界面方式修改内核配置选项
4、如何增加menuconfig配置选项
驱动目录下的kconfig文件，drivers\char\Kconfig
menu "Character devices"source "drivers/tty/Kconfig"config DEVMEMbool"/dev/mem virtual device support"default y help Say Y here if you want to support the /dev/mem device. The /dev/mem device is used to access areas of physical memory. When in doubt, say "Y"....endmenu
- menu "Character devices"
- source "drivers/tty/Kconfig" 类似C语言的包含头文件，包含更底层的目录的Kconfig配置文件
- config DEVMEM 菜单栏下的配置选项，在图形中该该选项会显示为CONFIG_DEVMEM
- bool 表明该选项是布尔选项，只能yes 或 no，后面的"/dev/mem virtual device support"为提示信息
- default y
- help
- endmenu
config SGI_MBCS tristate "SGI FPGA Core Services driver support" depends on SGI_TIOCX help If you have an SGI Altix with an attached SABrick say Y or M here, otherwise say N.
- tristate 中文意思为三态，即表示改配置选项可以为y、n以及m（配置进内核、不编译以及编译成模块）
Kconifg语法参考内核文件：Documentation\kbuild\kconfig-language.txt
内核源码根目录Kconfig内容：
# SPDX-License-Identifier: GPL-2.0## For a description of the syntax of this configuration file,# see Documentation/kbuild/kconfig-language.txt.#mainmenu "Linux/$(ARCH) $(KERNELVERSION) Kernel Configuration"comment "Compiler: $(CC_VERSION_TEXT)"source "scripts/Kconfig.include"source "init/Kconfig"source "kernel/Kconfig.freezer"source "fs/Kconfig.binfmt"source "mm/Kconfig"source "net/Kconfig"source "drivers/Kconfig"source "fs/Kconfig"source "security/Kconfig"source "crypto/Kconfig"source "lib/Kconfig"source "lib/Kconfig.debug"
- mainmenu， 生成主菜单，名字为"Linux/$(ARCH) $(KERNELVERSION) Kernel Configuration"
- source "mm/Kconfig"，包含底层目录的Kconfig配置文件，类似C语言包含头文件
通过分析Kconfig可以得出在内核中编译驱动的方法
将驱动文件添加到对应分类的驱动目录下。
比如，添加hy46xx_ts_drv.c 触摸驱动到内核编译
将驱动添加到该目录下：drivers\input\touchscreen\hy46xx_ts_drv.c
最快添加进内核编译的方法：修改drivers\input\touchscreen\Makefile
Makefile的内容：
obj-$(CONFIG_TOUCHSCREEN_PROPERTIES) += of_touchscreen.oobj-$(CONFIG_TOUCHSCREEN_88PM860X) += 88pm860x-ts.oobj-$(CONFIG_TOUCHSCREEN_AD7877) += ad7877.oobj-$(CONFIG_TOUCHSCREEN_AD7879) += ad7879.oobj-$(CONFIG_TOUCHSCREEN_AD7879_I2C) += ad7879-i2c.oobj-$(CONFIG_TOUCHSCREEN_AD7879_SPI) += ad7879-spi.oobj-$(CONFIG_TOUCHSCREEN_ADC) += resistive-adc-touch.oobj-$(CONFIG_TOUCHSCREEN_ADS7846) += ads7846.oobj-$(CONFIG_TOUCHSCREEN_AR1021_I2C) += ar1021_i2c.o...
添加一个编译项，直接将后面编译配置字段写为y，表示编译进内核
obj-y += hy46xx_ts_drv.o
另一种方法先修改Kconfig文件，添加hy46xx触摸的配置选项：
drivers\input\touchscreen\Kconfig
参考已有的配置项添加自己的hy46xx的配置项
config TOUCHSCREEN_HY46XX tristate "HYCON hy46xx I2C Touchscreen" depends on I2C help Say Y here if you have HYCON hy46xx series I2C touchscreen, connected to your system. If unsure, say N. To compile this driver as a module, choose M here: the module will be called hy46xx_ts_drv
最后通过make menuconfig进行配置，将TOUCHSCREEN_HY46XX配置选为y
