Linux驱动 | 调试宏和多平台兼容的Makefile

调试宏

将头文件driver.h包含到驱动文件中。

drvier.h

#ifndef __SCULL_H__
#define __SCULL_H__

#ifdef EN_DRIVER_DEBUG
    #ifdef __KERNEL__
    //处于内核空间
        #define PDEBUG(fmt,args...) printk(KERN_DEBUG fmt,##args)
    #else
    //处于用户空间
        #define PDEBUG(fmt,args...) fprintf(stderr,fmt,##args)
    #endif
#else
    //关闭调试
    #define PDEBUG(fmt,args...)
#endif
    

#endif

多平台兼容的Makefile

Makefile

obj-m += scull.o
PWD=$(shell pwd)
_KERDIR ?= /lib/modules/$(shell uname -r)/build
mips_KERDIR ?= /home/hjf/work/openwrt_widora/build_dir/target-mipsel_24kec+dsp_uClibc-0.9.33.2/linux-ramips_mt7688/linux-3.18.29
arm_KERDIR ?= /home/hjf/work/itop_4412/iTop4412_kernel_public
mips_TOOLCHAIN ?= /home/hjf/work/openwrt_widora/staging_dir/toolchain-mipsel_24kec+dsp_gcc-4.8-linaro_uClibc-0.9.33.2/bin/mipsel-openwrt-linux-
arm_TOOLCHAIN ?= /home/hjf/work/itop_4412/arm-linux-gcc-4.5.1/bin/arm-linux-

KERDIR ?= $($(ARCH)_KERDIR)
TOOLCHAIN ?= $($(ARCH)_TOOLCHAIN)
DEBUG ?= y

ifeq ($(DEBUG),y)
  DEBFLAGS = -O -g -DEN_DRIVER_DEBUG # "-O" is needed to expand inlines
else
  DEBFLAGS = -O2
endif

EXTRA_CFLAGS += $(DEBFLAGS)

ifeq ($(ARCH),)
	CROSS ?=
else
	CROSS ?= ARCH=$(ARCH) CROSS_COMPILE=$(TOOLCHAIN)
endif

modules:
	$(MAKE) -C $(KERDIR) M=$(PWD) $(CROSS) modules

clean:
	rm -rf *.ko *.o *.mod.c *.order *.symvers 

编译ARM平台：

make ARCH=arm

编译Mips平台：

make ARCH=mips

编译当前平台（一般是x86平台，默认使用gcc编译器）

make

启用调试

make DEBUG=y