003 Linux驱动开发——第一个简单开发实验
01 开发板的第 1 个 APP 实验
gcc -o hello hello.c
./hello
Hello, world!
./hello weidongshan
Hello, weidongshan!
要想给 ARM 板编译出 hello 程序，需要使用交叉编译工具链
arm-buildroot-linux-gnueabihf-gcc -o hello hello.c
这样编译出来的 hello 程序才可以在 ARM 板子上运行02 开发板的第 1 个驱动实验
编译内核
cd /home/book/100ask_imx6ull-sdk/Linux-4.9.88
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ make mrproper
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ make 100ask_imx6ull_defconfig
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ make zImage -j4
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ make dtbs
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ cp arch/arm/boot/zImage ~/nfs_rootfs
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ cp arch/arm/boot/dts/100ask_imx6ull-14x14.dtb ~/nfs_rootfs
编译内核模块：
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ make modules
把模块安装在 nfs 目录“/home/book/nfs_rootfs/”下：
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ make ARCH=arm INSTALL_MOD_PATH=/home/book/nfs_rootfs modules_install
安装内核和模块到开发板上：
[root@imx6ull:~]# cp /mnt/zImage /boot
[root@imx6ull:~]# cp /mnt/100ask_imx6ull-14x14.dtb /boot
[root@imx6ull:~]# cp /mnt/lib/modules /lib -rfd
[root@imx6ull:~]# sync
[root@imx6ull:~]# reboot
[root@imx6ull:~]# uname -a
Linux imx6ull 4.9.88 #1 SMP PREEMPT Sun Jan 19 23:26:58 EST 2025 armv7l GNU/Linux编译第一个hello驱动程序
对Ubuntu：
book@100ask:~$ cd nfs_rootfs/
book@100ask:~/nfs_rootfs$ ls
01_hello_drv 100ask_imx6ull-14x14.dtb drivers_projects lib zImage
book@100ask:~/nfs_rootfs$ cd 01_hello_drv/
book@100ask:~/nfs_rootfs/01_hello_drv$ cd ~/100ask_imx6ull-sdk/Linux-4.9.88
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ pwd
/home/book/100ask_imx6ull-sdk/Linux-4.9.88
book@100ask:~/100ask_imx6ull-sdk/Linux-4.9.88$ cd -
/home/book/nfs_rootfs/01_hello_drv
book@100ask:~/nfs_rootfs/01_hello_drv$ vi Makefile
book@100ask:~/nfs_rootfs/01_hello_drv$ make all对开发板：
同理驱动led程序：
对Ubuntu：
book@100ask:~/nfs_rootfs/drivers_projects$ ls
01_hello 01_hello_drv 02_led_drv
book@100ask:~/nfs_rootfs/drivers_projects$ cd 02_led_drv/
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv$ vi Makefile
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv$ ls
00_led_drv_simple 04_led_drv_template_bus_dev_drv
01_led_drv_template 04_led_drv_template_bus_dev_drv_unfinished
02_led_drv_for_boards 05_led_drv_template_device_tree
03_led_drv_template_seperate
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv$ ls
00_led_drv_simple 04_led_drv_template_bus_dev_drv
01_led_drv_template 04_led_drv_template_bus_dev_drv_unfinished
02_led_drv_for_boards 05_led_drv_template_device_tree
03_led_drv_template_seperate
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv$ cd 02_led_drv_for_boards/
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv/02_led_drv_for_boards$ ls
100ask_imx6ull-qemu_src_bin board_atk_imx6ull-alpha.c led_opr.h
100ask_imx6ull_src_bin board_demo.c ledtest.c
100ask_stm32mp157_src_bin board_fire_imx6ull-pro.c Makefile
am335x_src_bin board_rk3288.c rk3288_src_bin
atk_imx6ull-alpha_src_bin board_rk3399.c rk3399_src_bin
board_100ask_imx6ull-qemu.c fire_imx6ull-pro_src_bin
board_am335x.c leddrv.c
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv/02_led_drv_for_boards$ vi M akefile
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv/02_led_drv_for_boards$ make all
make -C /home/book/100ask_imx6ull-sdk/Linux-4.9.88 M=`pwd` modules
make[1]: Entering directory '/home/book/100ask_imx6ull-sdk/Linux-4.9.88'
Building modules, stage 2.
MODPOST 1 modules
make[1]: Leaving directory '/home/book/100ask_imx6ull-sdk/Linux-4.9.88'
arm-buildroot-linux-gnueabihf-gcc -o ledtest ledtest.c
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv/02_led_drv_for_boards$ ls
100ask_imx6ull-qemu_src_bin am335x_src_bin board_fire_imx6ull-pro.c ledtest
100ask_imx6ull_src_bin atk_imx6ull-alpha_src_bin board_rk3288.c ledtest.c
100ask_led.ko board_100ask_imx6ull-qemu.c board_rk3399.c Makefile
100ask_led.mod.c board_100ask_imx6ull-qemu.o fire_imx6ull-pro_src_bin modules.order
100ask_led.mod.o board_am335x.c leddrv.c Module.symvers
100ask_led.o board_atk_imx6ull-alpha.c leddrv.o rk3288_src_bin
100ask_stm32mp157_src_bin board_demo.c led_opr.h rk3399_src_bin
book@100ask:~/nfs_rootfs/drivers_projects/02_led_drv/02_led_drv_for_boards$ cp 100ask_led.ko ledtest ~/nfs_rootfs对开发板：
fs /mntmx6ull:~]# mount -t nfs -o nolock,vers=3 192.168.5.11:/home/book/nfs_rootf
[root@imx6ull:~]# cp /mnt/100ask_led.ko ./
[root@imx6ull:~]# cp /mnt/ledtest ./
[root@imx6ull:~]# echo none > /sys/class/leds/cpu/trigger
-bash: /sys/class/leds/cpu/trigger: No such file or directory报错不影响
[root@imx6ull:~]# insmod 100ask_led.ko
[ 3702.921183] 100ask_led: loading out-of-tree module taints kernel.提示内核污染不影响
[root@imx6ull:~]# lsmod查看是否安装成功
Module Size Used by
100ask_led 3995 0
inv_mpu6050_spi 2320 0
inv_mpu6050 11894 2 inv_mpu6050_spi
evbug 2282 0
[root@imx6ull:~]# chmod +x ./ledtest
[root@imx6ull:~]# ./ledtest
Usage: ./ledtest <dev> <on | off>
[root@imx6ull:~]# ./ledtest /dev/100ask_led0 on
[root@imx6ull:~]# ./ledtest /dev/100ask_led0 off